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Note: This page contains sample records for the topic "random vibration environment" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
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1

Random walks in random environments  

Science Journals Connector (OSTI)

A renormalization-group analysis is carried out of the long-time behavior of random walks in an environment with a positionally random local drift force. It is argued that, independent of the strength of the disorder, the mean-square displacement, ?x2(t)?, is linear in time (i.e., diffusive) for dimensions d?2. In two dimensions, universal tlnt corrections are found and for d=2-?, the behavior is subdiffusive with ?x2(t)??t1-?2.

Daniel S. Fisher

1984-08-01T23:59:59.000Z

2

Lattice Vibration and Random Walk Problems  

Science Journals Connector (OSTI)

......1960 research-article Articles Lattice Vibration and Random Walk Problems Ei Teramoto...Mathematical relations between the lattice vibration and the random walk problems are presented...the frequency spectrum of the lattice vibration can be expressed in terms of the transition......

Ei Teramoto

1960-12-01T23:59:59.000Z

3

Active vibration control in a microgravity environment  

E-Print Network (OSTI)

ACTIVE VIBRATION COiVTROL IN A MICROGRAVITY ENVIRONMENT A Thesis MYOUNG SOO PARK Submitted to the Graduate College of Texas A@M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE December 1987 Maior... Subject: Mechanical Engineering ACTIVE VIBRATION CONTROL IN A MICROGRAVITY ENVIRONMENT A Thesis by MYOUNG SOO PARK Approved as to style and content by: Dr. C. H. Gerhold (Chairman of Coxnmit tee) Dr. T ozi (Member) Dr. Y. XVe sman (Member) Dr...

Park, Myoung Soo

2012-06-07T23:59:59.000Z

4

Random walks in glasslike environments  

Science Journals Connector (OSTI)

We have considered in the framework of a renormalization-group approach the asymptotic behavior of a diffusive particle in an environment with quenched disorder and an additional dynamical feedback. The disorder is described by a spatially random drift force field; the feedback is controlled by a memory of strength ?. Both disorder and memory have proved to be relevant in d0) can be related to a superdiffusion (divergence-free drift forces), subdiffusion (random drift forces) or a localization of the particle (curl-free drift forces). The last regime shows an important agreement with the results of the well-known mode-coupling approach.

M. Schulz and S. Stepanow

1999-06-01T23:59:59.000Z

5

Random walk through fractal environments  

Science Journals Connector (OSTI)

We analyze random walk through fractal environments, embedded in three-dimensional, permeable space. Particles travel freely and are scattered off into random directions when they hit the fractal. The statistical distribution of the flight increments (i.e., of the displacements between two consecutive hittings) is analytically derived from a common, practical definition of fractal dimension, and it turns out to approximate quite well a power-law in the case where the dimension DF of the fractal is less than 2, there is though, always a finite rate of unaffected escape. Random walks through fractal sets with DF2 is decaying exponentially. The diffusive behavior of the random walk is analyzed in the frame of continuous time random walk, which we generalize to include the case of defective distributions of walk increments. It is shown that the particles undergo anomalous, enhanced diffusion for DF2 is normal for large times, enhanced though for small and intermediate times. In particular, it follows that fractals generated by a particular class of self-organized criticality models give rise to enhanced diffusion. The analytical results are illustrated by Monte Carlo simulations.

H. Isliker and L. Vlahos

2003-02-26T23:59:59.000Z

6

Experimental Analysis of a Piezoelectric Energy Harvesting System for Harmonic, Random, and Sine on Random Vibration  

SciTech Connect

Formal journal article Experimental analysis of a piezoelectric energy harvesting system for harmonic, random, and sine on random vibration Abstract: Harvesting power with a piezoelectric vibration powered generator using a full-wave rectifier conditioning circuit is experimentally compared for varying sinusoidal, random and sine on random (SOR) input vibration scenarios. Additionally, the implications of source vibration characteristics on harvester design are discussed. Studies in vibration harvesting have yielded numerous alternatives for harvesting electrical energy from vibrations but piezoceramics arose as the most compact, energy dense means of energy transduction. The rise in popularity of harvesting energy from ambient vibrations has made piezoelectric generators commercially available. Much of the available literature focuses on maximizing harvested power through nonlinear processing circuits that require accurate knowledge of generator internal mechanical and electrical characteristics and idealization of the input vibration source, which cannot be assumed in general application. In this manuscript, variations in source vibration and load resistance are explored for a commercially available piezoelectric generator. We characterize the source vibration by its acceleration response for repeatability and transcription to general application. The results agree with numerical and theoretical predictions for in previous literature that load optimal resistance varies with transducer natural frequency and source type, and the findings demonstrate that significant gains are seen with lower tuned transducer natural frequencies for similar source amplitudes. Going beyond idealized steady state sinusoidal and simplified random vibration input, SOR testing allows for more accurate representation of real world ambient vibration. It is shown that characteristic interactions from more complex vibrational sources significantly alter power generation and power processing requirements by increasing harvested power, shifting optimal conditioning impedance, inducing significant voltage supply fluctuations and ultimately rendering idealized sinusoidal and random analyses insufficient.

Cryns, Jackson W.; Hatchell, Brian K.; Santiago-Rojas, Emiliano; Silvers, Kurt L.

2013-07-01T23:59:59.000Z

7

COMPUTING THE DRIFT OF RANDOM WALKS IN DEPENDENT RANDOM ENVIRONMENTS  

E-Print Network (OSTI)

new theory and methodology for the computation of the drift of the random walk for various depen- dent for RWREs was laid by Solomon [13], who proved conditions for recurrence/transience for one with independent random environments. The purpose of this paper is to develop theory and methodology

Kroese, Dirk P.

8

Vibrational Signature of Water Molecules in Asymmetric Hydrogen Bonding Environments  

E-Print Network (OSTI)

Vibrational Signature of Water Molecules in Asymmetric Hydrogen Bonding Environments Chao Zhang contributions of each of the two hydrogen atoms to the vibrational modes 1 and 3 of water molecules the early works on the molecular structure of water, it has been accepted that a water molecule

Guidoni, Leonardo

9

Lévy Flights in Random Environments  

Science Journals Connector (OSTI)

We consider Lévy flights characterized by the step index f in a quenched isotropic short-range random force field to one loop order. By means of a dynamic renormalization group analysis, we find that the dynamic exponent z for f<2 locks onto f, independent of dimension and independent of the presence of weak quenched disorder. The critical dimension for f<2 is given by dc=2f-2. For d

Hans C. Fogedby

1994-11-07T23:59:59.000Z

10

Search in unknown random environments  

Science Journals Connector (OSTI)

N searchers are sent out by a source in order to locate a fixed object which is at a finite distance D, but the search space is infinite and D would be in general unknown. Each of the searchers has a finite random lifetime, and may be subject to destruction or failures, and it moves independently of other searchers, and at intermediate locations some partial random information may be available about which way to go. When a searcher is destroyed or disabled, or when it “dies naturally,” after some time the source becomes aware of this and it sends out another searcher, which proceeds similarly to the one that it replaces. The search ends when one of the searchers finds the object being sought. We use N coupled Brownian motions to derive a closed form expression for the average search time as a function of D which will depend on the parameters of the problem: the number of searchers, the average lifetime of searchers, the routing uncertainty, and the failure or destruction rate of searchers. We also examine the cost in terms of the total energy that is expended in the search.

Erol Gelenbe

2010-12-07T23:59:59.000Z

11

Modeling nonlinear random vibration: Implication of the energy conservation law  

E-Print Network (OSTI)

Nonlinear random vibration under excitations of both Gaussian and Poisson white noises is considered. The model is based on stochastic differential equations, and the corresponding stochastic integrals are defined in such a way that the energy conservation law is satisfied. It is shown that Stratonovich integral and Di Paola-Falsone integral should be used for excitations of Gaussian and Poisson white noises, respectively, in order for the model to satisfy the underlining physical laws (e.g., energy conservation). Numerical examples are presented to illustrate the theoretical results.

Xu Sun; Jinqiao Duan; Xiaofan Li

2012-06-18T23:59:59.000Z

12

Application of Random Vibration Theory Methodology for Seismic Soil-Structure Interaction Analysis  

Energy.gov (U.S. Department of Energy (DOE))

Application of Random Vibration Theory Methodology for Seismic Soil-Structure Interaction Analysis Farhang Ostadan Nan Deng Lisa Anderson Bechtel National, Inc. USDOE NPH Workshop October 2014

13

Lecture Notes on Random Walks in Random Environments  

E-Print Network (OSTI)

Under the quenched law Xn is a Markov chain, and so all the tools of ... of part of such an environment is shown in Figure 1.1 where sites with ?x = 3/4 are.

2013-02-21T23:59:59.000Z

14

Surviving particles for subcritical branching processes in random environment  

E-Print Network (OSTI)

Surviving particles for subcritical branching processes in random environment Vincent Bansaye December 9, 2008 Abstract The asymptotic behavior of a subcritical Branching Process in Random Envi- ronment (BPRE) starting with several particles depends on whether the BPRE is strongly subcritical (SS

Paris-Sud XI, Université de

15

The Gamow-Teller response within Skyrme random-phase approximation plus particle-vibration coupling  

E-Print Network (OSTI)

Although many random-phase approximation (RPA) calculations of the Gamow-Teller (GT) response exist, this is not the case for calculations going beyond the mean-field approximation. We apply a consistent model that includes the coupling of the GT resonance to low-lying vibrations, to nuclei of the $fp$ shell. Among other motivations, our goal is to see if the particle-vibration coupling can redistribute the low-lying GT$^+$ strength that is relevant for electron-capture processes in core-collapse supernova. We conclude that the lowering and fragmentation of that strength are consistent with the experimental findings and validate our model. However, the particle-vibration coupling cannot account for the quenching of the total value of the low-lying strength.

Yifei Niu; Gianluca Colo; Marco Brenna; Marco Brenna; Pier Francesco Bortignon; Jie Meng

2012-03-28T23:59:59.000Z

16

vibration  

Science Journals Connector (OSTI)

the rapid and promotion of a continuing periodic frequency in a displacement with respect to fixed reference. Lattice vibration .

2009-01-01T23:59:59.000Z

17

Directed polymers in a random environment with a defect line  

E-Print Network (OSTI)

We study the depinning transition of the $1+1$ dimensional directed polymer in a random environment with a defect line. The random environment consists of i.i.d. potential values assigned to each site of $\\mathbb{Z}^2$; sites on the positive axis have the potential enhanced by a deterministic value $u$. We show that for small inverse temperature $\\beta$ the quenched and annealed free energies differ significantly at most in a small neighborhood (of size of order $\\beta$) of the annealed critical point $u_c^a=0$. For the case $u=0$, we show that the difference between quenched and annealed free energies is of order $\\beta^4$ as $\\beta\\to 0$, assuming only finiteness of exponential moments of the potential values, improving existing results which required stronger assumptions.

Kenneth S. Alexander; Gökhan Yildirim

2014-02-26T23:59:59.000Z

18

vibration  

NLE Websites -- All DOE Office Websites (Extended Search)

Electronics Testing for Electronics Testing for NANOMETER VIBRATION READING on The Next Linear Collider Project SUMMER INTERN PROJECT Rachel Lansom, Advisor: Josef Frisch, Collaborator: Sara Waugh INTRODUCTION SYNTHESIZER TEST AMPLIFIER TEST THE STATIC ACCELEROMETER TESTING THE CAPACITOR CONCLUSION ACKNOWLEDGEMENTS REFERENCES The NLC when it is completed will consist of two separate beam lines about ten kilometers in length. The beams from these beam lines are expected to converge to a diameter of only a few nanometers just prior to annihilation. One of many problems associated with such small beams is the slight movement of the earth (vibration). These vibrations cause the focusing magnets to move the beams off their collision paths. The earth itself is rather vibrationally quiet, but cars, construction, industries, and human

19

Vibration Damping Control of Robot Arm Intended for Service Application in Human Environment  

E-Print Network (OSTI)

Vibration Damping Control of Robot Arm Intended for Service Application in Human Environment anthropomorphic robot arm enabling the torque measurement in each joint and tactile area recognition to ensure in heavily loaded joints have risen due to compliances introduced into each joint of the robot arm by means

Tachi, Susumu

20

Measuring Electrostatic Fields in Both Hydrogen-Bonding and Non-Hydrogen-Bonding Environments Using Carbonyl Vibrational Probes  

E-Print Network (OSTI)

of the probe's difference dipole, which is determined by measuring the vibrational Stark effect and definesMeasuring Electrostatic Fields in Both Hydrogen-Bonding and Non- Hydrogen-Bonding Environments Using Carbonyl Vibrational Probes Stephen D. Fried, Sayan Bagchi, and Steven G. Boxer* Department

Boxer, Steven G.

Note: This page contains sample records for the topic "random vibration environment" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Branching processes in random environment a view on critical and subcritical cases  

E-Print Network (OSTI)

Branching processes in random environment ­ a view on critical and subcritical cases M. Birkner1 environment. Then the transition from subcriticality to supercriticality proceeds in several steps, and there occurs a second `transition' in the subcritical phase (besides the phase-transition from (sub)criticality

Birkner, Matthias

22

2.017J / 1.015J Design of Systems Operating in Random Environments, Spring 2006  

E-Print Network (OSTI)

This class covers the principles for optimal performance and survival of extreme events in a random environment; linear time invariant systems and Fourier transform; random processes, autocorrelation function, and power ...

Hover, Franz

23

Downhole vibration sensing by vibration energy harvesting  

E-Print Network (OSTI)

This thesis outlines the design of a prototype electromagnetic induction vibration energy harvesting device for use in a downhole environment. First order models of the necessary components for a generic vibration energy ...

Trimble, A. Zachary

2007-01-01T23:59:59.000Z

24

Multi-Exciter Vibroacoustic Simulation of Hypersonic Flight Vibration  

SciTech Connect

Many aerospace structures must survive severe high frequency, hypersonic, random vibration during their flights. The random vibrations are generated by the turbulent boundary layer developed along the exterior of the structures during flight. These environments have not been simulated very well in the past using a fixed-based, single exciter input with an upper frequency range of 2 kHz. This study investigates the possibility of using acoustic ardor independently controlled multiple exciters to more accurately simulate hypersonic flight vibration. The test configuration, equipment, and methodology are described. Comparisons with actual flight measurements and previous single exciter simulations are also presented.

GREGORY,DANNY LYNN; CAP,JEROME S.; TOGAMI,THOMAS C.; NUSSER,MICHAEL A.; HOLLINGSHEAD,JAMES RONALD

1999-11-11T23:59:59.000Z

25

Measurement and bio-dynamic model development of seated human subjects exposed to low frequency vibration environment  

Science Journals Connector (OSTI)

In this study, the effect of posture, vibration magnitude and frequency on seat-to-head (STH) and back support-to-head (BTH) transfer functions has been studied under vertical sinusoidal vibration. Twelve healthy male subjects participated in experimental work to measure vertical vibration transmitted to the occupants' heads in three representative postures (erect, vertical backrest and forward lean on table) under three magnitudes of vibration (0.4, 0.8 and 1.2 m/s² r.m.s.) in frequency range 1 to 20 Hz. From collected data sets, the effects of vibration magnitude, vibration frequency and postures on STH and BTH transmissibility and phase were measured over the prescribed frequency range. The result suggested that inclusion of all possible variables in optimal design of vehicle seat, suspension and comfort analysis would improve the design and analysis. The comparison of experimental and model response reveals that both models matched with mean experimental data sets most closely and the models provide the best description of the biodynamic response of seated human subjects under vertical whole body vibration.

S.P. Harsha; Milk Desta; A.S. Prashanth; V.H. Saran

2014-01-01T23:59:59.000Z

26

vibration measurement  

Science Journals Connector (OSTI)

vibration measurement ? Erschütterungsmessung, Schwingungsmessung f [Schwingungsmessungen dienen dazu, die Schwingungsanfälligkeit von Bauwerken realitätsnah zu erfassen

2014-08-01T23:59:59.000Z

27

Multiple direction vibration fixture  

DOE Patents (OSTI)

An apparatus for simulating a rocket launch environment on a test item undergoing centrifuge testing by subjecting the item simultaneously or separately to vibration along an axis of centripetal force and along an axis perpendicular to the centripetal force axis. The apparatus includes a shaker motor supported by centrifuge arms and a right angle fixture pivotally connected to one of the shaker motor mounts. When the shaker motor vibrates along the centripetal force axis, the vibrations are imparted to a first side of the right angle fixture. The vibrations are transmitted 90 degrees around the pivot and are directed to a second side of the right angle fixture which imparts vibrations perpendicular to the centripetal force axis. The test item is in contact with a third side of the right angle fixture and receives both centripetal-force-axis vibrations and perpendicular axis vibrations simultaneously. A test item can be attached to the third side near the flexible coupling or near the air bag to obtain vibrations along the centripetal force axis or transverse to the centripetal force axis.

Cericola, Fred (Albuquerque, NM); Doggett, James W. (Albuquerque, NM); Ernest, Terry L. (Albuquerque, NM); Priddy, Tommy G. (Rockville, MD)

1991-01-01T23:59:59.000Z

28

2 - Fundamentals of vibrations  

Science Journals Connector (OSTI)

Abstract: An elastic system could exhibit oscillatory motion when external energy is supplied to the system. External energy can be supplied to the system through either an applied force or an imposed motion excitation. The applied force or motion excitation may be harmonic, periodic, nonperiodic, or random in nature. Real engineering systems can be modeled as discrete systems (single or multiple-degree-of-freedom system) or continuous system having an infinite number of degrees of freedom. The discrete system contains discrete masses and springs and even dampers, whereas the continuous system has distributed masses, springs and dampers. A vibration system may experience transient response under suddenly applied non-periodic excitation. The nondeterministic vibration of system under random excitation could be quantified by probabilistic analysis. The dynamical system’s parameters such as stiffness and damping could exhibit salient nonlinearity if the amplitude of motion is relatively large. Nonlinear system exhibit complicated vibrations such as primary resonance, super-and-sub harmonics, combination resonance, bifurcation and chaos. This chapter provides detailed discussion of single- and multiple-degree-of-freedom linear systems under harmonic excitations and random excitations. It will present the vibrations of continuous systems including string, rod and beam. This chapter will also present the methods to treat nonlinear systems, focusing on three kinds of typical nonlinear systems: Duffing equations, Van der Pol equations and Mathieu equations. This chapter will also brief the concept of bifurcation and chaos in nonlinear systems.

2014-01-01T23:59:59.000Z

29

Environment  

NLE Websites -- All DOE Office Websites (Extended Search)

Environment Environment Environment LANL's mission is to develop and apply science and technology to ensure the safety, security, and reliability of the U.S. nuclear deterrent; reduce global threats; and solve other emerging national security and energy challenges. Contact Operator Los Alamos National Laboratory (505) 667-5061 LANL has a strategy to clean up the past, control current operations, and move toward a sustainable future in which waste is minimized and other effects on the environment are reduced or eliminated. We work safely, securely, ethically, and in a manner that protects the environment We understand that the health and viability of the Laboratory depend in part on a record of environmental performance, building confidence of the public and our regulators. To gain the right to do what we do, we must work

30

Mechanical Vibration  

Science Journals Connector (OSTI)

... THE suppression and control of mechanical vibration have assumed great importance in engineering. One consequence of this is that the number ... degree of emphasis is placed on transient oscillation (in addition to steady-State and free vibration). The treatment of this topic is based mainly on phase-plane constructions and it ...

R. E. D. BISHOP

1958-12-06T23:59:59.000Z

31

Vibration Technology  

Science Journals Connector (OSTI)

... AT first sight, one has the impression that this is just another book on vibrations with the same old chapter headings as many others ; it is only when one ... with basic theory of the conventional systems having simple and multi-degrees of freedom and vibration of strings, bars and beams, but the treatment is unusual in that emphasis is ...

E. DOWNHAM

1969-01-18T23:59:59.000Z

32

Environment  

Science Journals Connector (OSTI)

...CLIMATE C 24 ( 1979 ). BOLIN, B.B., GLOBAL CARBON CYCLE 3 ( 1979...CHEM ENV NEWS 0406 ( 1976 ). FISCHHOFF, B, HANDLING HAZARDS, ENVIRONMENT...1978 ). LOWRANCE, W.W., ACCEPTABLE RISK ( 1976 ). MARSH, G.P., EARTH...

Gilbert F. White

1980-07-04T23:59:59.000Z

33

Environment  

NLE Websites -- All DOE Office Websites (Extended Search)

Environment Environment Environment Photo Gallery A repository for images showing environmental cleanup and protection efforts around the Lab. Click thumbnails to enlarge. Photos arranged by most recent first, horizontal formats before vertical. See Flickr for more sizes and details. Workers sample contents of LANL's Material Disposal Area B (MDA-B) before excavation Workers sample contents of LANL's Material Disposal Area B (MDA-B) before excavation Shipment #159 of TRU waste from LANL to WIPP, 2011 Shipment #159 of TRU waste from LANL to WIPP, 2011 Kathy Johns-Hughes oversees Los Alamos National Laboratory's TRU Waste Program Kathy Johns-Hughes oversees Los Alamos National Laboratory's TRU Waste Program Worker moves drums of transuranic (TRU) waste at a staging area

34

Environment  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

73 Federal Register 73 Federal Register / Vol. 77, No. 48 / Monday, March 12, 2012 / Rules and Regulations adopted by voluntary consensus standards bodies. This rule does not use technical standards. Therefore, we did not consider the use of voluntary consensus standards. Environment We have analyzed this rule under Department of Homeland Security Management Directive 023-01 and Commandant Instruction M16475.lD, which guide the Coast Guard in complying with the National Environmental Policy Act of 1969 (NEPA) (42 U.S.C. 4321-4370f), and have concluded this action is one of a category of actions that do not individually or cumulatively have a significant effect on the human environment. This rule is categorically excluded, under figure 2-1, paragraph (34)(g), of the Instruction. This rule

35

Molecular vibration demonstrations  

Science Journals Connector (OSTI)

Molecular vibration demonstrations ... Two dynamic models that illustrate the normal-mode vibrations of the water and benzene molecules. ...

George Turrell; Robert Demol

1987-01-01T23:59:59.000Z

36

VIBRATION CONTROL OF DISTRIBUTED PARAMETER SYSTEMSAND FLUIDIC FLEXIBLE MATRIX COMPOSITES.  

E-Print Network (OSTI)

??Vibration degrades the performance of many mechanical systems, reducing the qualityof manufactured products, producing noise, introducing fatigue in mechanical compo-nents, and generating an uncomfortable environment… (more)

Lotfi Gaskarimahalle, Amir

2009-01-01T23:59:59.000Z

37

Problems and Challenges Vibrations  

E-Print Network (OSTI)

, but is not necessary for many standard measurements. Mounting all optical components on vibration insulation posts further reduced vibrations. Concerning the suppression of vibration-induced measurement problems58 Problems and Challenges Vibrations: One of the key problems for the bulge tester is vibration

Huston, Dryver R.

38

Fundamental Vibration of Molecular Hydrogen  

Science Journals Connector (OSTI)

The fundamental ground tone vibration of H2, HD, and D2 is determined to an accuracy of 2×10-4??cm-1 from Doppler-free laser spectroscopy in the collisionless environment of a molecular beam. This rotationless vibrational splitting is derived from the combination difference between electronic excitation from the X1?g+, v=0, and v=1 levels to a common EF1?g+, v=0 level. Agreement within 1? between the experimental result and a full ab initio calculation provides a stringent test of quantum electrodynamics in a chemically bound system.

G. D. Dickenson; M. L. Niu; E. J. Salumbides; J. Komasa; K. S. E. Eikema; K. Pachucki; W. Ubachs

2013-05-08T23:59:59.000Z

39

System and method of active vibration control for an electro-mechanically cooled device  

DOE Patents (OSTI)

A system and method of active vibration control of an electro-mechanically cooled device is disclosed. A cryogenic cooling system is located within an environment. The cooling system is characterized by a vibration transfer function, which requires vibration transfer function coefficients. A vibration controller generates the vibration transfer function coefficients in response to various triggering events. The environments may differ by mounting apparatus, by proximity to vibration generating devices, or by temperature. The triggering event may be powering on the cooling system, reaching an operating temperature, or a reset action. A counterbalance responds to a drive signal generated by the vibration controller, based on the vibration signal and the vibration transfer function, which adjusts vibrations. The method first places a cryogenic cooling system within a first environment and then generates a first set of vibration transfer function coefficients, for a vibration transfer function of the cooling system. Next, the cryogenic cooling system is placed within a second environment and a second set of vibration transfer function coefficients are generated. Then, a counterbalance is driven, based on the vibration transfer function, to reduce vibrations received by a vibration sensitive element.

Lavietes, Anthony D. (Hayward, CA); Mauger, Joseph (Livermore, CA); Anderson, Eric H. (Mountain View, CA)

2000-01-01T23:59:59.000Z

40

DOWNHOLE VIBRATION MONITORING & CONTROL SYSTEM  

SciTech Connect

The deep hard rock drilling environment induces severe vibrations into the drillstring, which can cause reduced rates of penetration (ROP) and premature failure of the equipment. The only current means of controlling vibration under varying conditions is to change either the rotary speed or the weight-on-bit (WOB). These changes often reduce drilling efficiency. Conventional shock subs are useful in some situations, but often exacerbate the problems. The objective of this project is development of a unique system to monitor and control drilling vibrations in a ''smart'' drilling system. This system has two primary elements: (1) The first is an active vibration damper (AVD) to minimize harmful axial, lateral and torsional vibrations. The hardness of this damper will be continuously adjusted using a robust, fast-acting and reliable unique technology. (2) The second is a real-time system to monitor drillstring vibration, and related parameters. This monitor adjusts the damper according to local conditions. In some configurations, it may also send diagnostic information to the surface via real-time telemetry. The AVD is implemented in a configuration using magnetorheological (MR) fluid. By applying a current to the magnetic coils in the damper, the viscosity of the fluid can be changed rapidly, thereby altering the damping coefficient in response to the measured motion of the tool. Phase I of this program entailed modeling and design of the necessary subsystems and design, manufacture and test of a full laboratory prototype. Phase I of the project was completed by the revised end date of May 31, 2004. The objectives of this phase were met, and all prerequisites for Phase II have been completed.

Martin E. Cobern

2004-08-31T23:59:59.000Z

Note: This page contains sample records for the topic "random vibration environment" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Diaphragm vibrator test rack  

Science Journals Connector (OSTI)

The above diaphragm-type vibrators provide sinusoidal vibrations at an amplitudea of ? 2000–3000 g at four fixed frequencies in the range of 1.5–4.0 kc, with a load not exceeding 100–200 g.

A. P. Pleshko; V. V. Perfil'ev

1961-02-01T23:59:59.000Z

42

Ground Vibration Measurement  

Science Journals Connector (OSTI)

Measurement of ground vibration is important for checking of amplitudes of ... confirmation of efficiency of control measures of ground vibration. The properties of measuring instruments used can affect the resul...

Dr. Milutin Srbulov

2010-01-01T23:59:59.000Z

43

Vibration Measurement and Monitoring  

Science Journals Connector (OSTI)

Successful vibration measurement and analysis require an intimate familiarity with types of measurement, transducer characteristics and application, plus the...

V. Schlegel

1984-01-01T23:59:59.000Z

44

Heterodyne vibration measurement  

Science Journals Connector (OSTI)

Analytic expressions are derived for the vibration amplitude and frequency in a heterodyne measurement method. The measurement accuracy is estimated.

A. A. Titov

1993-08-01T23:59:59.000Z

45

Vibration Perception by Chaetognaths  

Science Journals Connector (OSTI)

... to locate and attack prey, the prey must be actively moving-that is, producing vibrations and turbulence.

T. K. NEWBURY

1972-04-28T23:59:59.000Z

46

Noise & Vibration Ctrl What's noise and what's vibration?  

E-Print Network (OSTI)

Institut für Technische Akustik Noise & Vibration Ctrl · What's noise and what's vibration? ­ Noise = unwanted sound ­ Vibration = oscillations of structures © Prof. B.A.T. Petersson #12;Institut für Technische Akustik Noise & Vibration Ctrl. · What's Noise & Vibration Control? Genera t ion Transmiss ion

Berlin,Technische Universität

47

Vibration of a Pipeline with Liquid Under Combined Vibration Perturbations  

Science Journals Connector (OSTI)

We study the influence of combined vibration perturbations on the vibration of a pipeline with flowing liquid. The ... nonlinear model of a pipeline whose foundation suffers vibration perturbations in the longitu...

V. O. Limarchenko

2014-09-01T23:59:59.000Z

48

Superprocesses in a Brownian environment  

Science Journals Connector (OSTI)

...research-article Superprocesses in a Brownian environment Dan Crisan Department of Mathematics...related to an exterior process (the environment). We characterize these superprocesses...branching rates. Superprocesses|Random Environment|Uniqueness In Distribution| 10...

2004-01-01T23:59:59.000Z

49

Vibrational shortcut to the mean-first-passage-time problem  

Science Journals Connector (OSTI)

What is the average time a random walker takes to get from A to B on a fractal structure and how does this mean time scale with the size of the system and the distance between source and target? We take a nonprobabilistic approach toward this problem and show how the solution is readily obtained using an analysis of thermal vibrations on fractals. Invariance under scaling and continuity with respect to the spectral dimension are shown to be emergent properties of the solution obtained via vibrational analysis. Our result emphasizes the duality between diffusion and vibrations on fractal structures. Applications to biological systems are discussed.

Shlomi Reuveni; Rony Granek; Joseph Klafter

2010-04-26T23:59:59.000Z

50

Vibration in Engineering  

Science Journals Connector (OSTI)

... THE theory of vibrations has in recent years A become of dominating importance in engineering. It is well ... A become of dominating importance in engineering. It is well known, for example, that vibrations in heavy machinery may be of a destructive nature, causing failures in the machines ...

1935-08-10T23:59:59.000Z

51

Vibration insensitive optical cavity  

Science Journals Connector (OSTI)

An optical cavity is designed and implemented that is insensitive to vibration in all directions. The cavity is mounted with its optical axis in the horizontal plane. A minimum response of 0.1 (3.7)kHz?ms?2 is achieved for low-frequency vertical (horizontal) vibrations.

S. A. Webster; M. Oxborrow; P. Gill

2007-01-09T23:59:59.000Z

52

Vibration in Engineering  

Science Journals Connector (OSTI)

... to be solved have been arranged. Among the subjects chosen for the Cambridge meeting was vibration, a phenomenon which, in this mechanical age, is in daily evidence to every ... concerned with the discomfort (and even, maybe, injury to health), which accompanies continuous vibration. From whichever point of view it is regarded, therefore, ...

1938-10-15T23:59:59.000Z

53

Electron Trapping by Molecular Vibration  

NLE Websites -- All DOE Office Websites (Extended Search)

Electron Trapping by Molecular Vibration Electron Trapping by Molecular Vibration Print Wednesday, 27 April 2005 00:00 In photoelectron spectroscopy experiments performed at the...

54

Examples of vibration measurements  

Science Journals Connector (OSTI)

A detailed treatment of the vibration measurement techniques, applied in various fields of engineering ... only some of the most widely used modern measurement methods will be briefly presented, as well...

Gheorghe Buzdugan; Elena Mih?ilescu; Mircea Rade?

1986-01-01T23:59:59.000Z

55

2008 Vibrational Spectroscopy  

SciTech Connect

The conference focuses on using vibrational spectroscopy to probe structure and dynamics of molecules in gases, liquids, and interfaces. The goal is to bring together a collection of researchers who share common interests and who will gain from discussing work at the forefront of several connected areas. The intent is to emphasize the insights and understanding that studies of vibrations provide about a variety of systems.

Philip J. Reid

2009-09-21T23:59:59.000Z

56

vibrations.dvi  

NLE Websites -- All DOE Office Websites (Extended Search)

VIBRATIONAL VIBRATIONAL MEASUREMENTS IN 3-ID-B J. Sutter 1 , E. Alp 1 , J. Barraza 2 , D. Shu 2 1 INTRODUCTION We have undertaken a series of vibrational measurements in hutch 3-ID-B. Our motivation was to compare two di erent methods of mounting an interferometer for e ectiveness in vibrational isolation and stability. In addition, we were able to compare the stability of our optical table with and without its eight large bolts inserted. 2 PROCEDURE We used two accelerometers to measure the amplitude of the vibrational acceleration as a function of frequency in steps of 0.0625 Hz from 1 to 25 Hz. The accelerations could then be transformed into displacement amplitudes by the simple harmonic equation of motion x = ,! 2 x, where x is the displacement and ! is the frequency times 2. The accelerometers had been calibrated before our experiment and were found to output a voltage of 7:44G V=g,

57

Fiber optic vibration sensor  

DOE Patents (OSTI)

A fiber optic vibration sensor utilizes two single mode optical fibers supported by a housing with one optical fiber fixedly secured to the housing and providing a reference signal and the other optical fiber having a free span length subject to vibrational displacement thereof with respect to the housing and the first optical fiber for providing a signal indicative of a measurement of any perturbation of the sensor. Damping or tailoring of the sensor to be responsive to selected levels of perturbation is provided by altering the diameter of optical fibers or by immersing at least a portion of the free span length of the vibration sensing optical fiber into a liquid of a selected viscosity.

Dooley, Joseph B. (Harriman, TN); Muhs, Jeffrey D. (Lenoir City, TN); Tobin, Kenneth W. (Harriman, TN)

1995-01-01T23:59:59.000Z

58

Fiber optic vibration sensor  

DOE Patents (OSTI)

A fiber optic vibration sensor utilizes two single mode optical fibers supported by a housing with one optical fiber fixedly secured to the housing and providing a reference signal and the other optical fiber having a free span length subject to vibrational displacement thereof with respect to the housing and the first optical fiber for providing a signal indicative of a measurement of any perturbation of the sensor. Damping or tailoring of the sensor to be responsive to selected levels of perturbation is provided by altering the diameter of optical fibers or by immersing at least a portion of the free span length of the vibration sensing optical fiber into a liquid of a selected viscosity. 2 figures.

Dooley, J.B.; Muhs, J.D.; Tobin, K.W.

1995-01-10T23:59:59.000Z

59

Externally tuned vibration absorber  

DOE Patents (OSTI)

A vibration absorber unit or units are mounted on the exterior housing of a hydraulic drive system of the type that is powered from a pressure wave generated, e.g., by a Stirling engine. The hydraulic drive system employs a piston which is hydraulically driven to oscillate in a direction perpendicular to the axis of the hydraulic drive system. The vibration absorbers each include a spring or other resilient member having one side affixed to the housing and another side to which an absorber mass is affixed. In a preferred embodiment, a pair of vibration absorbers is employed, each absorber being formed of a pair of leaf spring assemblies, between which the absorber mass is suspended.

Vincent, Ronald J. (Latham, NY)

1987-09-22T23:59:59.000Z

60

Vibration by relativistic effects  

E-Print Network (OSTI)

Relativity, time reversal invariance in mechanics and principle of causality can be in the bases of a type of vibration of the extensive objects. It is because, the detailed analysis of the relativistic movement of an extensive body entail that all the objects must have inherent a vibratory movement to their own size. Such effect does not happen when it works with point particles thus is not stranger who happens unnoticed in the traditional studies. Also we can find relation between the form of vibration of the extensive objects and the energy that calculates by quantum considerations.

Enrique Oradaz Romay

2005-12-23T23:59:59.000Z

Note: This page contains sample records for the topic "random vibration environment" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Fundamental discussions on seismic vibrators  

Science Journals Connector (OSTI)

...now ConocoPhillips) with a trailer-mounted swing weight vibrator...an application of a servo-hydraulic vibrator with a peak-force...paper demonstrated the servo-hydraulic vibrator capability to deliver...as indicated in the book, Hydraulic Control Systems (Merritt...

Zhouhong Wei; Thomas F. Phillips; Michael A. Hall

62

4 - Friction–vibration interactions  

Science Journals Connector (OSTI)

Abstract: Generally, friction could be treated as a dynamical variable in a dynamical system with a sliding interface. For convenience, the effect of friction on vibrations and the effect of vibrations on friction have been treated separately. The close-loop feedback effects of friction–vibration interactions have rarely been paid attention due to limited engineering applications. Both friction and vibration have been simplified and quantified by order-reduced models. There are many unique dynamic phenomena and underlying mechanisms associated with the vibrations of a system with friction, just to name a few: stick-slip, self-excited vibrations, modal coupling, sprag-slip, loss of contact, parametric resonance, etc. Friction-induced vibrations usually exhibit time-varying, nonlinear and stochastic properties. On the other hand, there are certain underlying mechanisms associated with the effect of vibrations on the friction reductions. This chapter will comprehensively survey varied characteristics of vibrations in systems having friction. Then a detailed consideration of the current understanding of vibration-induced friction reduction will be given. Also the single-degree-of-freedom system, multiple-degree-of-freedom system and continuous system are discussed. Finally, several applications in science and engineering are presented, which include stick-slip associated with earthquakes, friction vibrations of rod in sucker pumping system, and automotive brake vibrations and noise.

2014-01-01T23:59:59.000Z

63

Nonlinear vibrational microscopy  

DOE Patents (OSTI)

The present invention is a method and apparatus for microscopic vibrational imaging using coherent Anti-Stokes Raman Scattering or Sum Frequency Generation. Microscopic imaging with a vibrational spectroscopic contrast is achieved by generating signals in a nonlinear optical process and spatially resolved detection of the signals. The spatial resolution is attained by minimizing the spot size of the optical interrogation beams on the sample. Minimizing the spot size relies upon a. directing at least two substantially co-axial laser beams (interrogation beams) through a microscope objective providing a focal spot on the sample; b. collecting a signal beam together with a residual beam from the at least two co-axial laser beams after passing through the sample; c. removing the residual beam; and d. detecting the signal beam thereby creating said pixel. The method has significantly higher spatial resolution then IR microscopy and higher sensitivity than spontaneous Raman microscopy with much lower average excitation powers. CARS and SFG microscopy does not rely on the presence of fluorophores, but retains the resolution and three-dimensional sectioning capability of confocal and two-photon fluorescence microscopy. Complementary to these techniques, CARS and SFG microscopy provides a contrast mechanism based on vibrational spectroscopy. This vibrational contrast mechanism, combined with an unprecedented high sensitivity at a tolerable laser power level, provides a new approach for microscopic investigations of chemical and biological samples.

Holtom, Gary R. (Richland, WA); Xie, Xiaoliang Sunney (Richland, WA); Zumbusch, Andreas (Munchen, DE)

2000-01-01T23:59:59.000Z

64

Vibration sensing method and apparatus  

DOE Patents (OSTI)

A method and apparatus for nondestructive evaluation of a structure are disclosed. Resonant audio frequency vibrations are excited in the structure to be evaluated and the vibrations are measured and characterized to obtain information about the structure. The vibrations are measured and characterized by reflecting a laser beam from the vibrating structure and directing a substantial portion of the reflected beam back into the laser device used to produce the beam which device is capable of producing an electric signal containing information about the vibration. 4 figs.

Barna, B.A.

1989-04-25T23:59:59.000Z

65

Vibration sensing method and apparatus  

DOE Patents (OSTI)

A method and apparatus for nondestructive evaluation of a structure is disclosed. Resonant audio frequency vibrations are excited in the structure to be evaluated and the vibrations are measured and characterized to obtain information about the structure. The vibrations are measured and characterized by reflecting a laser beam from the vibrating structure and directing a substantial portion of the reflected beam back into the laser device used to produce the beam which device is capable of producing an electric signal containing information about the vibration.

Barna, Basil A. (Idaho Falls, ID)

1989-04-25T23:59:59.000Z

66

Vibration sensing method and apparatus  

DOE Patents (OSTI)

A method and apparatus for nondestructive evaluation of a structure is disclosed. Resonant audio frequency vibrations are excited in the structure to be evaluated and the vibrations are measured and characterized to obtain information about the structure. The vibrations are measured and characterized by reflecting a laser beam from the vibrating structure and directing a substantial portion of the reflected beam back into the laser device used to produce the beam which device is capable of producing an electric signal containing information about the vibration. 4 figs.

Barna, B.A.

1987-07-07T23:59:59.000Z

67

Localized Surface Plasmons in Vibrating Graphene Nanodisks  

E-Print Network (OSTI)

Localized surface plasmons are confined collective oscillations of electrons in metallic nanoparticles. When driven by light, the optical response is dictated by geometrical parameters and the dielectric environment and plasmons are therefore extremely important for sensing applications. Plasmons in graphene disks have the additional benefit to be highly tunable via electrical stimulation. Mechanical vibrations create structural deformations in ways where the excitation of localized surface plasmons can be strongly modulated. We show that the spectral shift in such a scenario is determined by a complex interplay between the symmetry and shape of the modal vibrations and the plasmonic mode pattern. Tuning confined modes of light in graphene via acoustic excitations, paves new avenues in shaping the sensitivity of plasmonic detectors, and in the enhancement of the interaction with optical emitters, such as molecules, for future nanophotonic devices.

Wang, Weihua; Mortensen, N Asger; Christensen, Johan

2015-01-01T23:59:59.000Z

68

A broadband vibrational energy harvester Louis Van Blarigan, Per Danzl, and Jeff Moehlisa)  

E-Print Network (OSTI)

vibrational energy harvesters are com- posed of a mass-spring system with a transducer,1 where vibrations in the surrounding environment act as inputs and cause the spring-mass system to oscillate. The oscillations of buckling, as measured by d. The mount is attached to a voice-coil shaker and shaken vertically

Bigelow, Stephen

69

Vibration damping method and apparatus  

DOE Patents (OSTI)

The present invention provides vibration damping method and apparatus that can damp vibration in more than one direction without requiring disassembly, that can accommodate varying tool dimensions without requiring re-tuning, and that does not interfere with tool tip operations and cooling. The present invention provides active dampening by generating bending moments internal to a structure such as a boring bar to dampen vibration thereof.

Redmond, James M. (Albuquerque, NM); Barney, Patrick S. (Albuquerque, NM); Parker, Gordon G. (Hougton, MI); Smith, David A. (Gainesville, FL)

1999-01-01T23:59:59.000Z

70

Mini genset for vibration measurement.  

E-Print Network (OSTI)

??Detta examensarbete gjordes vid Wärtsilä Service, Vibration Environmental and Measurement Technologies i Runsor, Vasa. Syftet med detta examensarbete var att designa och bygga ett minigenset… (more)

Mann, Dennis

2012-01-01T23:59:59.000Z

71

Electron Trapping by Molecular Vibration  

NLE Websites -- All DOE Office Websites (Extended Search)

Electron Trapping by Molecular Vibration Print In photoelectron spectroscopy experiments performed at the ALS, a group of researchers has found that electronic transitions normally...

72

Vibration-Rotation Bands of Trideuteromethyl Iodide  

Science Journals Connector (OSTI)

5 October 1965 research-article Vibration-Rotation Bands of Trideuteromethyl...of six parallel and nine perpendicular vibration bands of trideuteromethyl iodide has...constants for the fundamental degenerate vibrations. The values for overtone and combination...

1965-01-01T23:59:59.000Z

73

Vibration Theory and Engineering Practice  

Science Journals Connector (OSTI)

... INTRICATE vibration phenomena have at all times attracted the attention of the physical investigator, and ... phenomena have at all times attracted the attention of the physical investigator, and vibration theory is a wide field well and fruitfully cultivated by the mathematician. The achievements ...

1929-10-05T23:59:59.000Z

74

Mechanical Impedance Methods in Vibration  

Science Journals Connector (OSTI)

... THE basic theory of linear mechanical vibration has been in existence for many years. Unfortunately, in some respects that theory is ... in some respects that theory is not in a convenient form for use in modern vibration analysis. Much effort has therefore been put into re-casting, tabulating, re-examining ...

R. E. D. BISHOP

1959-12-05T23:59:59.000Z

75

Sum Frequency Generation for Surface Vibrational Spectroscopy...  

NLE Websites -- All DOE Office Websites (Extended Search)

Sum Frequency Generation for Surface Vibrational Spectroscopy Sum Frequency Generation for Surface Vibrational Spectroscopy This customized SFG-VS spectrometer incorporates unique...

76

Vibrational relaxation of trapped molecules  

Science Journals Connector (OSTI)

Vibrational relaxation of trapped molecules due to collisions with cold atoms is investigated using the results of quantum-mechanical scattering calculations. Trap loss is analyzed using an exactly solvable kinetic model that includes direct collisional quenching and an indirect process of vibrational predissociation. At low atom density, the relaxation is due primarily to collisional quenching. At high atom density, the relaxation involves additional time scales due to the formation and decay of van der Waals complexes. It is shown that the most weakly bound state of the van der Waals complex for a given diatomic vibrational level controls the relaxation at all atom densities. Possible experiments using trapped molecules are discussed.

R. C. Forrey; V. Kharchenko; N. Balakrishnan; A. Dalgarno

1999-03-01T23:59:59.000Z

77

Measurement of underwater vibration by ultrasonic speckle stroboscopic technique  

Science Journals Connector (OSTI)

Abstract Ultrasonic speckles are widely used in medical imaging, but are not commonly accepted in industry. An ultrasonic speckle stroboscopic technique for industrial applications is introduced in this manuscript. In this technique, a whole field ultrasonic speckle image converter is no longer needed as in B-mode scanning, and neither is the process of searching for the maximum correlation coefficient among sub-sets in the ultrasonic speckle field. In pulse-echo working mode, by the modulation of sweeping frequency and trigger delay and performing a digital speckle correlation calculation, it can be obtained point-to-point the vibration frequency, amplitude and phase difference of underwater solid surfaces. Compared with traditional vibration measurement techniques, ultrasonic speckle stroboscopic technique can perform on-line, underwater, noncontact experiments, and is insensitive to the environment and the sample surface roughness. In this manuscript this technique was applied to a vibrating cantilever underwater. The experimental results were in good agreement with other testing methods. Therefore, the noncontact testing technique for vibration coefficient, especially the vibration phase difference, provides an alternative method for the mode analysis of industrial constructions, which is a piece of very important work for industrial underwater structure design.

Zhihua Luo; Jun Chu; Lei Shen; Peng Hu; Hongmao Zhu; Lili Hu

2014-01-01T23:59:59.000Z

78

Rectangular Parallelepiped Vibration in Plane Strain State  

E-Print Network (OSTI)

In this paper we present a vibration spectrum of a homogenous parallelepiped (HP) under the action of volume and surface forces resulting from the exponent displacements entering the Fourier transforms. Vibration under the action of axial surface tractions and the free vibration are described separately. A relationship between the high frequency vibration and boundary conditions (BC) is also considered.

Jerzy Hanckowiak

2004-11-25T23:59:59.000Z

79

Vibration dampener for dampening vibration of a tubular member  

DOE Patents (OSTI)

Vibration dampener for dampening vibration of a tubular member, such as an instrumentation tube of the type found in nuclear reactor pressure vessels. The instrumentation tube is received in an outer tubular member, such as a guide thimble tube. The vibration dampener comprises an annular sleeve which is attachable to the inside surface of the guide thimble tube and which is sized to surround the instrumentation tube. Dimples are attached to the interior wall of the sleeve for radially supporting the instrumentation tube. The wall of the sleeve has a flexible spring member, which is formed from the wall, disposed opposite the dimples for biasing the instrumentation tube into abutment with the dimples. Flow-induced vibration of the instrumentation tube will cause it to move out of contact with the dimples and further engage the spring member, which will flex a predetermined amount and exert a reactive force against the instrumentation tube to restrain its movement. The amount by which the spring member will flex is less than the unrestrained amplitude of vibration of the instrumentation tube. The reactive force exerted against the instrumentation tube will be sufficient to return it to its original axial position within the thimble tube. In this manner, vibration of the instrumentation tube is dampened so that in-core physics measurements are accurate and so that the instrumentation tube will not wear against the inside surface of the guide thimble tube.

Obermeyer, Franklin D. (Pensacola, FL); Middlebrooks, Willis B. (Pensacola, FL); DeMario, Edmund E. (Columbia, SC)

1994-01-01T23:59:59.000Z

80

Vibration dampener for dampening vibration of a tubular member  

DOE Patents (OSTI)

Vibration dampener for dampening vibration of a tubular member, such as an instrumentation tube of the type found in nuclear reactor pressure vessels is disclosed. The instrumentation tube is received in an outer tubular member, such as a guide thimble tube. The vibration dampener comprises an annular sleeve which is attachable to the inside surface of the guide thimble tube and which is sized to surround the instrumentation tube. Dimples are attached to the interior wall of the sleeve for radially supporting the instrumentation tube. The wall of the sleeve has a flexible spring member, which is formed from the wall, disposed opposite the dimples for biasing the instrumentation tube into abutment with the dimples. Flow-induced vibration of the instrumentation tube will cause it to move out of contact with the dimples and further engage the spring member, which will flex a predetermined amount and exert a reactive force against the instrumentation tube to restrain its movement. The amount by which the spring member will flex is less than the unrestrained amplitude of vibration of the instrumentation tube. The reactive force exerted against the instrumentation tube will be sufficient to return it to its original axial position within the thimble tube. In this manner, vibration of the instrumentation tube is dampened so that in-core physics measurements are accurate and so that the instrumentation tube will not wear against the inside surface of the guide thimble tube. 14 figs.

Obermeyer, F.D.; Middlebrooks, W.B.; DeMario, E.E.

1994-10-18T23:59:59.000Z

Note: This page contains sample records for the topic "random vibration environment" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

Randomized Algorithms Robert Elsasser  

E-Print Network (OSTI)

Randomized Algorithms Robert Els¨asser 15. June 2011 Program of the day: · Random walks on graphs Robert Els¨asser Universit¨at Paderborn Randomized Algorithms SS 11 0 #12;Markov Chains and Random Walks¨asser Universit¨at Paderborn Randomized Algorithms SS 11 1 #12;Markov Chains and Random Walks A Markov chain M

Elsässer, Robert

82

Electron Trapping by Molecular Vibration  

NLE Websites -- All DOE Office Websites (Extended Search)

Electron Trapping by Molecular Vibration Print Electron Trapping by Molecular Vibration Print In photoelectron spectroscopy experiments performed at the ALS, a group of researchers has found that electronic transitions normally thought to be forbidden can in fact be excited in conjunction with certain types of molecular vibrations. Specifically, they found that when the symmetry of a linear triatomic molecule is broken by asymmetric vibrational modes, photoelectrons can become temporarily trapped by the molecule before ultimately escaping, giving rise to a broad feature in the photoelectron spectrum known as a shape resonance. This process represents a novel type of symmetry-breaking phenomenon that has not been observed previously but appears to be widespread. Such coupling between electronic motion and nuclear motion becomes increasingly important as scientists learn more about the geometry and dynamics of novel chemical structures such as those found in nanodevices and transient chemical species, and the results have implications for studies that use photoelectron spectroscopy as a diagnostic tool.

83

Electron Trapping by Molecular Vibration  

NLE Websites -- All DOE Office Websites (Extended Search)

Electron Trapping by Molecular Vibration Print Electron Trapping by Molecular Vibration Print In photoelectron spectroscopy experiments performed at the ALS, a group of researchers has found that electronic transitions normally thought to be forbidden can in fact be excited in conjunction with certain types of molecular vibrations. Specifically, they found that when the symmetry of a linear triatomic molecule is broken by asymmetric vibrational modes, photoelectrons can become temporarily trapped by the molecule before ultimately escaping, giving rise to a broad feature in the photoelectron spectrum known as a shape resonance. This process represents a novel type of symmetry-breaking phenomenon that has not been observed previously but appears to be widespread. Such coupling between electronic motion and nuclear motion becomes increasingly important as scientists learn more about the geometry and dynamics of novel chemical structures such as those found in nanodevices and transient chemical species, and the results have implications for studies that use photoelectron spectroscopy as a diagnostic tool.

84

Vibration Harvesting using Electromagnetic Transduction  

E-Print Network (OSTI)

spectra for (a) a 30 kW water pump motor, and (b) vibrationCondenser water supply Power [kW] Motor #1 and motor #3 were1 Motor # 2 Motor #3 Function Chilled water supply Process

Waterbury, Andrew

2011-01-01T23:59:59.000Z

85

Vibration of Tethered Microstructure Profilers  

Science Journals Connector (OSTI)

Although loosely tethered turbulence profilers have many advantages, they are prone to resonant vibrations at frequencies in the dissipation range when they are falling rapidly or when the tether is strummed. Using the Advanced Microstructure ...

Jack B. Miller; M. C. Gregg; Vernon W. Miller; Gordon L. Welsh

1989-12-01T23:59:59.000Z

86

Vibration isolators for oil- and gas-transfer equipment with a low vibration frequency  

Science Journals Connector (OSTI)

The negative effect of vibration on entities used for the transport of ... Systems with quasi-zero stiffness are employed as vibration isolators with a low natural-vibration frequency. The effectiveness of such u...

A. R. Valeev

2011-09-01T23:59:59.000Z

87

Vibration diagnosis and remediation design for an x-ray optics stitching interferometer system.  

SciTech Connect

The Advanced Photon Source (APS) x-ray optics Metrology Laboratory currently operates a small-aperture Wyko laser interferometer in a stitching configuration. While the stitching configuration allows for easier surface characterization of long x-ray substrates and mirrors, the addition of mechanical components for optic element translation can compromise the ultimate measurement performance of the interferometer. A program of experimental vibration measurements, quantifying the laboratory vibration environment and identifying interferometer support-system behavior, has been conducted. Insight gained from the ambient vibration assessment and modal analysis has guided the development of a remediation technique. Discussion of the problem diagnosis and possible solutions are presented in this paper.

Preissner, C.; Assoufid, L.; Shu, D.; Experimental Facilities Division (APS)

2004-01-01T23:59:59.000Z

88

The potential energy of biased random walks on trees Yueyun Hu and Zhan Shi  

E-Print Network (OSTI)

The potential energy of biased random walks on trees by Yueyun Hu and Zhan Shi Universit´e Paris­Watson tree, branching random walk, slow movement, random walk in a random environment, potential energy. 2010 XIII & Universit´e Paris VI Summary. Biased random walks on supercritical Galton­Watson trees

Paris-Sud XI, Université de

89

Vibration-based structural health monitoring of highway bridges  

E-Print Network (OSTI)

the use of vibration measurement for damage identification.shape extracted from vibration measurements is used as thespatial resolution vibration measurement technique such as

Guan, Hong

2006-01-01T23:59:59.000Z

90

Vibration Phase Based Ordering of Vibration Patterns Acquired With a Shearing Speckle Interferometer and Pulsed Illumination  

Science Journals Connector (OSTI)

Harmonic vibrations of diffusely reflecting objects can be visualized ... period that is relatively long compared to the vibration period, time average interferograms are obtained,...

Peter A. A. M. Somers; Nandini Bhattacharya

2007-01-01T23:59:59.000Z

91

The Vibration of Bells  

Science Journals Connector (OSTI)

Relative frequencies, nodal meridians, and nodal circles of the bells of the Harkness Memorial Chime.—This is a study of the ten bells of the Harkness Memorial Chime at Yale University. The large size of these bells makes it possible to examine partial tones of higher order than could be studied on smaller bells. For the first ten partials the average values found for the relative frequencies, the numbers of nodal meridians, and the numbers of nodal circles are shown in the following table. Partial12345678910Relative Frequency0.501.001.201.492.002.562.963.283.804.06Nodal Meridians4466881081012Nodal Circles0111122    The nodal circles for the 2d, 3d, 4th, and 5th partials are at levels about 13, ½, 16, and ½ the height of the bell, those for the 6th partial are roughly at 15 and 35, for the 7th at 25 and 45 of the height.Amplitudes of the partials.—Curves showing the vibration in the air near the bells were obtained by a microphone, amplifier, and oscillograph. There is first an irregular motion which may arise from noises in the mechanism by which the bells are struck. The clapper probably strikes after some 0.01 sec. to 0.03 sec., for after this time the amplitude is larger and the curve more regular. Since the partial tones of a bell are not harmonic a Fourier analysis is not directly applicable, but a modified Fourier analysis may be employed. An approximation to the amplitude of each component is obtained by proceeding as if a Fourier analysis were being made, the range of integration for each component being however independently chosen as a whole number of periods of that component. A method is given for obtaining corrections to the approximate amplitudes thus found.The strike note of bells.—The curious phenomenon of the strike note is considered. The hypothesis that the pitch of the strike note is determined by that of the fifth partial, but that it is very generally judged an octave lower, is supported by several facts which have been already known and by the new fact that the fifth partial appears with surprising promptness and vigor. One possible cause for such a misjudging of the octave is the fact that the fifth, seventh, and tenth partials are all brought out well when a bell is struck on the soundbow, and that the relative frequencies of these partials are not far from 2:3:4, thus perhaps giving rise in the ear of the observer to the pitch of the strike note.

Arthur Taber Jones

1928-06-01T23:59:59.000Z

92

Hydrodynamics of vibrated granular monolayer.  

SciTech Connect

We investigate the long-standing puzzle of phase separation in a granular monolayer vibrated from below. Although this system is three dimensional, an interesting dynamics occurs mostly in the horizontal plane, perpendicular to the direction of vibration. Experiments [Olafsen and Urbach, Phys. Rev. Lett. 81 4369 (1998)] demonstrated that for a high amplitude of vibration the system is in the gaslike phase, but when the amplitude becomes smaller than a certain threshold, a phase separation occurs: A solidlike dense condensate of particles forms in the center of the system, surrounded by particles in the gaslike phase. We explain theoretically the experimentally observed coexistence of dilute and dense phases, employing Navier-Stokes granular hydrodynamics. We show that the phase separation is associated with a negative compressibility of granular gas.

Khain, E.; Aranson, I. S. (Materials Science Division); (Oakland Univ.)

2011-01-01T23:59:59.000Z

93

The Vibration of Piezoelectric Plates  

Science Journals Connector (OSTI)

The characteristic frequencies of infinite piezoelectric plates vibrating between the grounded electrodes of a plane parallel condenser have been rigorously investigated. It is found that the frequencies depend on the piezoelectric constants as well as the elastic constants of the crystal. The effective elastic constants for a piezoelectric crystal do not in general satisfy the same symmetry relations as the true elastic constants. For odd harmonics, which are the only modes which can be excited by a uniform electric field, the strain does not vanish at the surface of the plate for a finite gap between the electrodes. Consequently, the frequencies of free vibration also depend on the separation of the electrodes, and the rigorous theory shows this dependence should not be linear as hitherto supposed. The effect of the gap decreases as the square of the harmonic number and hence the higher frequencies of vibration are not exactly harmonics of the fundamental.

A. W. Lawson

1942-07-01T23:59:59.000Z

94

Design of Vibration Absorbers for Step Motions and Step Disturbances  

E-Print Network (OSTI)

Design of Vibration Absorbers for Step Motions and Step Disturbances Joel Fortgang William Singhose or from external disturbances. The technique of adding a vibration ab- sorber has proven useful at eliminating vibrations from external disturbances and rotational imbalances. Traditionally, vibration

Singhose, William

95

Visualization of vibration experienced in offshore platforms  

E-Print Network (OSTI)

In this thesis, I design and evaluate methods to optimize the visualization of vortex-induced vibration (VIV) in marine risers. VIV is vibration experienced by marine risers in offshore drilling platforms due to ocean ...

Patrikalakis, Alexander Marinos Charles

2010-01-01T23:59:59.000Z

96

Method of vibration measurements in heterodyne interferometry  

Science Journals Connector (OSTI)

A novel method is presented for determining the vibration amplitude of a vibrating fringe pattern in the presence of a low-frequency heterodyne phase shift. It consists of counting the...

Stetson, Karl A

1982-01-01T23:59:59.000Z

97

Optical instrumentation for vibration measurement and monitoring  

Science Journals Connector (OSTI)

Monitoring of machine tool vibrations is an important aspect of precision manufacturing ... of a simple and unique instrument for precise vibration measurement that can be used in industry. The ... laboratory. Th...

Devdas Shetty; Ahad Ali; Jonathan Hill

2011-06-01T23:59:59.000Z

98

Comparison of Torsional Vibration Measurement Techniques  

Science Journals Connector (OSTI)

Noise and vibration performance plays an important role in the ... compressors and pumps. The presence of torsional vibrations and other specific phenomena require the dynamic ... of the instrumentation and chall...

Karl Janssens; Laurent Britte

2014-01-01T23:59:59.000Z

99

Windowed defocused photographic speckle vibration measurement  

Science Journals Connector (OSTI)

The out-of-plane vibration of a rough surface causes an in-plane vibration of its speckle pattern when observed with a defocused optical photographic system. If the frequency of the...

Diazdelacruz, Jose

2009-01-01T23:59:59.000Z

100

Interferometric vibration measurement using optical fiber  

Science Journals Connector (OSTI)

The measurement of vibration generally requires the determination of the displacement ... function of time. The aim of the measurement is to determine the amplitude and frequency content of the vibration, or trac...

K. Weir; B. T. Meggitt

1998-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "random vibration environment" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

Neuromotor Transmissibility of Horizontal Seatpan Vibration  

E-Print Network (OSTI)

Exposure to occupational whole body vibration (WBV) is associated with low back pain disorders, musculoskeletal disorders, and degeneration of spine. Transmission of vibration to the neuromotor system may play a role in the etiology...

Channamallu, Raghu Ram

2007-12-16T23:59:59.000Z

102

Vibration Transmission through Symmetric Resonant Couplings  

Science Journals Connector (OSTI)

15 March 1994 research-article Vibration Transmission through Symmetric Resonant Couplings D. J. Allwright...Blakemore P. R. Brazier-Smith J. Woodhouse The transmission of vibration through a symmetric junction is considered. The problem is...

1994-01-01T23:59:59.000Z

103

Nonlinearity in modal and vibration testing.  

SciTech Connect

This set of slides describes some aspects of nonlinear Vibration analysis thru use of analytical fromulas and Examples from real or simulated test systems . The Systems are drawn from a set of examples based on Years of vibration testing experience . Both traditional and new methods are used to describe nonlinear vibration.

Hunter, N. F. (Norman F.)

2003-01-01T23:59:59.000Z

104

The Vibration of Electrified Water Drops  

Science Journals Connector (OSTI)

4 May 1971 research-article The Vibration of Electrified Water Drops P. R. Brazier-Smith...calculations concerned with charged drops. The vibration of water drops of radius around 2 mm...electrodes. Photographic analysis of the vibrations revealed good agreement between theory...

1971-01-01T23:59:59.000Z

105

Ground Vibration Measurements at LHC Point 4  

SciTech Connect

Ground vibration was measured at Large Hadron Collider (LHC) Point 4 during the winter shutdown in February 2012. This report contains the results, including power and coherence spectra. We plan to collect and analyze vibration data from representative collider halls to inform specifications for future linear colliders, such as ILC and CLIC. We are especially interested in vibration correlations between final focus lens locations.

Bertsche, Kirk; /SLAC; Gaddi, Andrea; /CERN

2012-09-17T23:59:59.000Z

106

Vibration–based structural damage identification  

Science Journals Connector (OSTI)

...N. A. J. Lieven and D. J. Ewins Vibration-based structural damage identification...identification based upon changes in vibration characteristics is one of the few methods...last thirty years is first presented. Vibration-based damage detection is a primary...

2001-01-01T23:59:59.000Z

107

Electron Trapping by Molecular Vibration  

NLE Websites -- All DOE Office Websites (Extended Search)

Electron Trapping by Molecular Electron Trapping by Molecular Vibration Electron Trapping by Molecular Vibration Print Wednesday, 27 April 2005 00:00 In photoelectron spectroscopy experiments performed at the ALS, a group of researchers has found that electronic transitions normally thought to be forbidden can in fact be excited in conjunction with certain types of molecular vibrations. Specifically, they found that when the symmetry of a linear triatomic molecule is broken by asymmetric vibrational modes, photoelectrons can become temporarily trapped by the molecule before ultimately escaping, giving rise to a broad feature in the photoelectron spectrum known as a shape resonance. This process represents a novel type of symmetry-breaking phenomenon that has not been observed previously but appears to be widespread. Such coupling between electronic motion and nuclear motion becomes increasingly important as scientists learn more about the geometry and dynamics of novel chemical structures such as those found in nanodevices and transient chemical species, and the results have implications for studies that use photoelectron spectroscopy as a diagnostic tool.

108

Vibrational amplitudes in vitreous silica  

Science Journals Connector (OSTI)

A model structure of vitreous silica, for which the vibrational frequencies and eigenmodes were calculated from first principles, is used to investigate vibrational amplitudes. Calculated mean-square displacements for oxygen and silicon atoms are obtained as a function of temperature. The square displacement tensors of oxygen atoms show a marked anisotropic character, which is related to the local geometry. The displacements of oxygen atoms along the three principal directions can be associated to distinct parts of the vibrational spectrum, as evidenced by their thermal dependence. These anisotropic effects directly affect the elastic and the static structure factors, which are sensitive to the correlation between displacements of different atoms along their connecting direction. This description shows that the observed widths for Si-O and O-O correlations mainly derive from atomic vibrations rather than from structural disorder. Anisotropic correlations between different atoms are shown to be important up to a distance of 4 Å, i.e., involving atoms that belong to corner-sharing tetrahedra. The scattering functions, calculated at finite temperature and in the harmonic approximation, show good agreement with experiment. In particular, the comparison between the static and the elastic structure factors yields a characterization of the correlated displacements in accord with experimental observations. The static structure factor is significantly affected by anisotropic correlations, but shows only a weak dependence on temperature between 0 and 300 K.

Alfredo Pasquarello

2000-02-01T23:59:59.000Z

109

CN vibration–rotation spectrum  

Science Journals Connector (OSTI)

CN vibration–rotation bands for the sequences (1–0) through (4–3) and (2–0) through (4–2) were observed in a King furnace and measured in the spectral regions 1797–2208 and 3740–4156...

Davis, Sumner P; Brault, James W; Abrams, Mark C; Rao, M L P

1991-01-01T23:59:59.000Z

110

Wind farm—Long term noise and vibration measurements  

Science Journals Connector (OSTI)

Most of the energy produced in Quebec comes from renewable sources. The concept of wind energy emerged in the late 1990’s and has since become a complementary source of energy alongside hydroelectricity. Wind farms are generally seen as a good sustainable way to produce energy. However they are not implemented without some impact on the environment. SNC-Lavalin Environment has performed many surveys in recent years for wind farm projects including noise measurements both before and after their commissioning. This presentation will give an overview of one such project where long term noise and vibration measurements where conducted. Vibration measurements as well as outdoor indoor and low frequencies noise measurements were completed both with and without the wind turbines in operation. Data will be presented showing different problems encountered in the analysis phase. For example multiple intermittent and non-steady noise sources were present during measurement (wind turbines car pass-bys wind in the trees human activities). Methods used to overcome these obstacles will be discussed (use of statistical parameters linear regression) and the effect of the wind turbine operation on the noise level (including low frequencies) and vibration level will be presented.

2013-01-01T23:59:59.000Z

111

Wind Farm - Long term noise and vibration measurements  

Science Journals Connector (OSTI)

Most of the energy produced in Quebec comes from renewable sources. The concept of wind energy emerged in the late 1990's and has since become a complementary source of energy alongside hydroelectricity. Wind farms are generally seen as a good sustainable way to produce energy. However they are not implemented without some impact on the environment. SNC-Lavalin Environment has performed many surveys in recent years for wind farm projects including noise measurements both before and after their commissioning. This presentation will give an overview of one such project where long term noise and vibration measurements where conducted. Vibration measurements as well as outdoor indoor and low frequencies noise measurements were completed both with and without the wind turbines in operation. Data will be presented showing different problems encountered in the analysis phase. For example multiple intermittent and non-steady noise sources were present during measurement (wind turbines car pass-bys wind in the trees human activities). Methods used to overcome these obstacles will be discussed (use of statistical parameters linear regression) and the effect of the wind turbine operation on the noise level (including low frequencies) and vibration level will be presented.

Martin Meunier

2013-01-01T23:59:59.000Z

112

Method for enriching a middle isotope using vibration-vibration pumping  

DOE Patents (OSTI)

Method for producing isotopically enriched material by vibration-vibration excitation of gaseous molecules wherein a middle mass isotope of an isotopic mixture including lighter and heavier mass isotopes preferentially populates a higher vibrational mode and chemically reacts to provide a product in which it is enriched. The method can be used for vibration-vibration enrichment of .sup.17 O in a CO reactant mixture.

Rich, Joseph W. (East Aurora, NY); Homicz, Gregory F. (Getzville, NY); Bergman, Richard C. (Corfu, NY)

1989-01-01T23:59:59.000Z

113

Vibration of Nanoparticles in Viscous Fluids  

Science Journals Connector (OSTI)

In this article, we present results of a rigorous finite-element analysis and commensurate scaling theory that enable interpretation and analysis of these experiments, for the extensional vibrational modes of axisymmetric nanoparticles immersed in viscous fluids. ... (51) Vibration of the particle accelerates the fluid, which increases the effective mass of the vibrating particle. ... Using low-frequency Raman scattering, the authors clearly demonstrate that single-domain NCs vibrate differently than their multiply twinned counterparts, through the splitting of the quadrupolar vibrations, which is only obsd. ...

Debadi Chakraborty; Emma van Leeuwen; Matthew Pelton; John E. Sader

2013-03-21T23:59:59.000Z

114

Vibration-based damage identification and health monitoring of civil structures  

E-Print Network (OSTI)

from ambient vibration measurements on a bridge. ” Journalmodal parameters from vibration measurements. In classicalshapes) from vibration measurements. These modal parameters

He, Xianfei

2008-01-01T23:59:59.000Z

115

Algebraic methods in vibrational spectroscopy  

SciTech Connect

These lectures review some advances in the algebraic description of molecules from two point of views: structure and dynamics. We start by presenting the basic ideas involved in the traditional description of molecular structure in configuration space, where the Born-Oppenheimer and rotor-rigid approximations are assumed to be valid. We then focus on the vibrational degrees of freedom in order to introduce the traditional algebraic realization in terms of bosonic operators of harmonic oscillators. This analysis allows the algebraic methods based on dynamical unitary groups to be introduced as a anharmonization procedure where the local bosonic operators are translated into operators satisfying the su(2) commutation relations. Some examples of the vibrational spec-troscopic description are presented. Concerned with the dynamical point of view an algebraic model to describe collinear collisions in the semiclassical approximation is presented.

Lemus, Renato [Instituto de Ciencias Nucleares, Universidad Nacional Autonoma de Mexico, Apartado Postal 70-543, 04510 Mexico, DF (Mexico)

2011-03-21T23:59:59.000Z

116

Vibration-enhanced quantum transport  

E-Print Network (OSTI)

In this paper, we study the role of collective vibrational motion in the phenomenon of electronic energy transfer (EET) along a chain of coupled electronic dipoles with varying excitation frequencies. Previous experimental work on EET in conjugated polymer samples has suggested that the common structural framework of the macromolecule introduces correlations in the energy gap fluctuations which cause coherent EET. Inspired by these results, we present a simple model in which a driven nanomechanical resonator mode modulates the excitation energy of coupled quantum dots and find that this can indeed lead to an enhancement in the transport of excitations across the quantum network. Disorder of the on-site energies is a key requirement for this to occur. We also show that in this solid state system phase information is partially retained in the transfer process, as experimentally demonstrated in conjugated polymer samples. Consequently, this mechanism of vibration enhanced quantum transport might find applications in quantum information transfer of qubit states or entanglement.

F. L. Semião; K. Furuya; G. J. Milburn

2009-09-09T23:59:59.000Z

117

12 - Vibration Problem-Solving in Grinding  

Science Journals Connector (OSTI)

The first priority in overcoming vibration problems is to recognize the source and nature of the vibrations. Vibrations in grinding lead to surface waviness and loss of workpiece accuracy. Wheel wear is increased and workpiece roughness deteriorates. Sources of machine vibrations are introduced including impulsive vibrations, cyclic forced vibrations and self-excited regenerative vibrations. Regenerative vibrations include work-regenerative and wheel-regenerative vibrations. Dynamic relationships for grinding are discussed including equations of motion, feedback terms and forcing terms. Equations are presented in transfer function form including the depth of cut function, the compliance function and the wheel wear function. General solutions are given. The effect of contact length filtering is explained. Experimental results are presented for typical machine frequency responses. The nature of vibration modes is explained with examples. Theoretical effects of machine stiffness, damping and resonance characteristics are presented. Grinding chatter is explained using graphical stability determination from measured frequency responses. It is shown that the onset of instability depends on the maximum negative real in-phase component of the frequency response. The effect of overlap in traverse grinding is analysed and the benefits of reducing grinding contact stiffness by reducing wheel contact width, by introducing flexibility into the grinding wheel or introducing flexibility at the grinding wheel contact point, are discussed. Other possibilities are suggested to reduce incidence of vibrations. The main techniques for overcoming vibration problems are summarized. It is generally advisable to avoid integer speed ratios between wheel speed and work speed or between wheel speed and dressing roll speed. Chapter 13 includes further analysis of vibrations applied to centreless grinding with emphasis on critical speed relationships.

W. Brian Rowe

2014-01-01T23:59:59.000Z

118

Smoothness- transferred random field  

E-Print Network (OSTI)

We propose a new random field (RF) model, smoothness-transfer random field (ST-RF) model, for image modeling. In the objective function of RF models, smoothness energy is defined with compatibility function to capture the ...

Wei, Donglai

2013-01-01T23:59:59.000Z

119

GRANULAR MATERIALS UNDER VIBRATION AND THERMAL CYCLES.  

E-Print Network (OSTI)

??We report flow rate measurement of granular materials from a lab size silo with and without sinusoidal vibration, and the flows from a jammed container… (more)

Chen, Ke

2008-01-01T23:59:59.000Z

120

Human response to combined noise and vibration.  

E-Print Network (OSTI)

??The discomfort caused by the noise and vibration in cars is investigated in this thesis to improve understanding of how subjective judgements of noise and… (more)

Huang, Yuan

2012-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "random vibration environment" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

Vibration assisted filling of thin section castings.  

E-Print Network (OSTI)

??Understanding of the mechanism of the vibration needed to fill thin section or one with sharp edges in profile shapes and clarifying the dominant control… (more)

Abdul Karem, Waleed

2009-01-01T23:59:59.000Z

122

Effect of vibration exposure duration on discomfort.  

E-Print Network (OSTI)

??The comfort of a seated person exposed to vibration is known to depend on the magnitude, frequency content, and direction of the excitation. A review… (more)

Gallais, Cedric

2008-01-01T23:59:59.000Z

123

Flow-induced vibration: 1992  

SciTech Connect

A joint program on flow-induced vibration (FIV) as established in July 1988 between Taiwan Power Company (Taipower or TPC) and ANL. The main objectives of the program are to provide a technology transfer program on FIV for Taipower staff and to assist Taipower with various aspects of FIV including evaluation of reports and proposals, review of designs, resolution of design issues, recommendation for design modifications, and selected research studies. During the first two years, the following tasks were accomplished: A technology transfer program on FIV was completed and key Taipower staff members were prepared to handle future problems in the subject area. The modified component cooling water (CCW) heat exchangers were assessed and the basis for a license from the Taiwan Atomic Energy Council (AEC) was established. The seismic reanalysis of Chin Shan spent-fuel racks was assessed and a report was submitted to the Taiwan AEC. Fluid/structure interaction activities were coordinated and provided a list of potential bidders for a fluid transient project and related publications and a recommendation for purchasing technical data on fluid coupling. Flow-induced vibration of tube arrays was reviewed and the needs of Taipower in the area of fluid/structure interaction were identified as were the procedures necessary for Taipower to accomplish its goals. A computer program, ARRAY, was established to compute the added-mass matrices for tube arrays. Taipower expressed interest in extending the joint program so that ANL could provide continuing assistance. The program was extended for several years (May 1, 1991, to June 30, 1994). Work from May 1, 1991, through June 30, 1992, summarized in this report, included technology transfer, assessment of sensing line and valve vibrations, literature survey, and tests on motion-dependent fluid forces acting on tube arrays in crossflow.

Chen, S.S.

1992-09-01T23:59:59.000Z

124

Vibration modes of giant gravitons  

Science Journals Connector (OSTI)

We examine the spectrum of small vibrations of giant gravitons when the gravitons expand in anti–de Sitter space and when they expand on the sphere. For any given angular harmonic, the modes are found to have frequencies related to the curvature length scale of the background; these frequencies are independent of radius (and hence angular momentum) of the brane itself. This implies that the holographic dual theory must have, in a given R charge sector, low-lying non-BPS excitations with level spacings independent of the R charge.

Sumit R. Das; Antal Jevicki; Samir D. Mathur

2000-12-21T23:59:59.000Z

125

Preliminary Experiment for the Control of Cluster Vibration  

E-Print Network (OSTI)

(= 32.8 nm) to probe the vibration. The absorption of x-ray pulses is measured. We want to find of Cluster Vibration for the Control of Cluster Vibration 99 7 20 1. 15 3 http

126

An Integrated Measurement to Road Vibration Simulation System  

E-Print Network (OSTI)

An Integrated Measurement to Road Vibration Simulation System Charles Birdsong, Ph.D. Dactron Inc for vibrations measured on a Jeep, compensated, and replicated on an electrodynamic shaker. Introduction. Simulation of measured vibrations requires data acquisition, data compensation, and reproduction

Birdsong, Charles

127

VIBRATION OF CERTAIN SQUARE PLATES HAVING SIMILAR ADJACENT EDGES  

Science Journals Connector (OSTI)

......Press 1955 research-article Articles VIBRATION OF CERTAIN SQUARE PLATES HAVING SIMILAR...The fundamental frequencies of flexural vibration are determined for thin uniform elastic...to obtain the approximate solutions. VIBRATION OF CERTAIN SQUARE PLATES HAVING SIMILAR......

HUGH L. COX

1955-01-01T23:59:59.000Z

128

Electron–Vibration Interaction in Multichannel Single-Molecule Junctions  

Science Journals Connector (OSTI)

The electron-vibration coupling gives rise to small drops in the conductance at voltages corresponding to energies of some of the vibrational modes. ... where only the apex atoms are allowed to vibrate. ... We explore a full range of parameters going from weak to strong electron-vibration coupling, from tunneling to contact, and from 1-vibration description to the need of including all vibrations for a correct description of inelastic effects in transport. ...

Regev Ben-Zvi; Ran Vardimon; Tamar Yelin; Oren Tal

2013-11-19T23:59:59.000Z

129

Vibrations of raised access floors  

Science Journals Connector (OSTI)

Raised access floors play a critical role in modern cleanroom design. They have unique mechanical properties that make them respond to dynamic loading in a manner quite different from conventional floors. For example an unbraced floor is much more flexible horizontally than in the vertical direction. Horizontal vibration amplitudes with walker excitation may exceed 100??m/s in an unbraced floor exceeding the sensitivity of 1000× inspection microscopes by as much as an order of magnitude. Issues such as these become important when moderately vibration?sensitive instruments such as optical microscopes are supported on access floors typically the case in cleanrooms. This paper presents results of experimental studies involving a 3?m×3?m segment of floor and a large floor installed in a cleanroom both of which were subjected to dynamic loads using a shaker. Both drive?point and propagation properties were examined. In addition data are presented for variations in bracing and bolting using the 3?m×3?m segment.

2002-01-01T23:59:59.000Z

130

DOWNHOLE VIBRATION MONITORING & CONTROL SYSTEM  

SciTech Connect

The objective of this program is to develop a system to both monitor the vibration of a bottomhole assembly, and to adjust the properties of an active damper in response to these measured vibrations. Phase I of this program, which entailed modeling and design of the necessary subsystems and design, manufacture and test of a full laboratory prototype, was completed on May 31, 2004. The principal objectives of Phase II are: more extensive laboratory testing, including the evaluation of different feedback algorithms for control of the damper; design and manufacture of a field prototype system; and, testing of the field prototype in drilling laboratories and test wells. Work during this quarter centered on the rebuilding of the prototype using the improved valve design described in the last report. Most of the components have been received and assembly has begun. Testing is expected to resume in August. In April, a paper was presented at the American Association of Drilling Engineers National Technical Conference in Houston. The paper was well received, and several oilfield service and supply companies sent inquiries regarding commercial distribution of the system. These are currently being pursued, but none have yet been finalized.

Martin E. Cobern

2005-07-27T23:59:59.000Z

131

Vibration of Glasses containing Effervescing Liquids  

Science Journals Connector (OSTI)

... of the phenomena, he says:—“We must consider what passes in the communication of vibrations through the liquid from one side of the glass to the other. The glass ... it is clear, that if any considerable part of a system be unsusceptible of regular vibration, the whole must be so.” The phenomenon, then, according to this explanation, ...

ALLEN BEAZELEY

1872-07-18T23:59:59.000Z

132

Vibration of Gun-Barrels1  

Science Journals Connector (OSTI)

... THIS research on the vibration of gun-barrels is a continuation of former investigations on the nature of ... of gun-barrels is a continuation of former investigations on the nature of vibrations set up in a gun-barrel when fixed, with a view to discover how ...

F. J.-S

1901-01-17T23:59:59.000Z

133

DSB-SC Phase Demodulation -Application for Vibration Measurement  

Science Journals Connector (OSTI)

A heterodyne interferometry with DSB-SC performance is presented to measure small vibration signal. The vibration induced phase is demodulated by self-mixing without a local...

Teng, Hui-Kang; Lang, Kuo-Chen

134

Operando Raman and Theoretical Vibration Spectroscopy of Non...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Operando Raman and Theoretical Vibration Spectroscopy of Non-PGM Catalysts Operando Raman and Theoretical Vibration Spectroscopy of Non-PGM Catalysts Presentation about...

135

Noise and Vibration Control of Combustion Engine Vehicles.  

E-Print Network (OSTI)

??Noise and vibrations have over the last two decades been regarded as significant environmental health problems. Regulations regarding acoustic as well as vibration levels have… (more)

Winberg, Mathias

2005-01-01T23:59:59.000Z

136

Vibration-rotation spectrum of HCl: A physical chemistry experiment  

Science Journals Connector (OSTI)

Vibration-rotation spectrum of HCl: A physical chemistry experiment ... Utilizing a 0.5 cm−1 resolution teaching grade FTIR spectrometer, 15 vibrational ... ...

Fred E. Stafford; C. W. Holt; G. L. Paulson

1963-01-01T23:59:59.000Z

137

User Environment  

NLE Websites -- All DOE Office Websites (Extended Search)

User Environment Environment on Genepool When you log into the Genepool system you will land in your $HOME directory on NERSC's "global homes" file system. The global homes file system is mounted across all NERSC computation systems with the exception of PDSF. The $HOME directory has quota of 40GB and 1,000,000 inodes. To customize your environment, by setting environment variables or aliases, you will need to modify one of the "dot" files that NERSC has created for you. You may NOT modify the .bashrc or .cshrc files. These are set to read-only on NERSC systems and specify system specific customizations. Instead you should modify a file called .bashrc.ext or .cshrc.ext. Learn more about the global homes user environment. Important Environment Variables

138

Random coincidence of $2\  

E-Print Network (OSTI)

Two neutrino double $\\beta$ decay can create irremovable background even in high energy resolution detectors searching for neutrinoless double $\\beta$ decay due to random coincidence of $2\

D. M. Chernyak; F. A. Danevich; A. Giuliani; E. Olivieri; M. Tenconi; V. I. Tretyak

2013-01-17T23:59:59.000Z

139

Particle-vibration coupling within covariant density functional theory  

E-Print Network (OSTI)

Covariant density functional theory, which has so far been applied only within the framework of static and time dependent mean field theory is extended to include Particle-Vibration Coupling (PVC) in a consistent way. Starting from a conventional energy functional we calculate the low-lying collective vibrations in Relativistic Random Phase Approximation (RRPA) and construct an energy dependent self-energy for the Dyson equation. The resulting Bethe-Salpeter equation in the particle-hole ($ph$) channel is solved in the Time Blocking Approximation (TBA). No additional parameters are used and double counting is avoided by a proper subtraction method. The same energy functional, i.e. the same set of coupling constants, generates the Dirac-Hartree single-particle spectrum, the static part of the residual $ph$-interaction and the particle-phonon coupling vertices. Therefore a fully consistent description of nuclear excited states is developed. This method is applied for an investigation of damping phenomena in the spherical nuclei with closed shells $^{208}$Pb and $^{132}$Sn. Since the phonon coupling terms enrich the RRPA spectrum with a multitude of $ph\\otimes$phonon components a noticeable fragmentation of the giant resonances is found, which is in full agreement with experimental data and with results of the semi-phenomenological non-relativistic approach.

E. Litvinova; P. Ring; V. Tselyaev

2007-05-08T23:59:59.000Z

140

Reduced vibration motor winding arrangement  

DOE Patents (OSTI)

An individual phase winding arrangement having a sixty electrical degree phase belt width for use with a three phase motor armature includes a delta connected phase winding portion and a wye connected phase winding portion. Both the delta and wye connected phase winding portions have a thirty electrical degree phase belt width. The delta and wye connected phase winding portions are each formed from a preselected number of individual coils each formed, in turn, from an unequal number of electrical conductor turns in the approximate ratio of {radical}3. The individual coils of the delta and wye connected phase winding portions may either be connected in series or parallel. This arrangement provides an armature winding for a three phase motor which retains the benefits of the widely known and utilized thirty degree phase belt concept, including improved mmf waveform and fundamental distribution factor, with consequent reduced vibrations and improved efficiency. 4 figs.

Slavik, C.J.; Rhudy, R.G.; Bushman, R.E.

1997-11-11T23:59:59.000Z

Note: This page contains sample records for the topic "random vibration environment" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

Reduced vibration motor winding arrangement  

DOE Patents (OSTI)

An individual phase winding arrangement having a sixty electrical degree phase belt width for use with a three phase motor armature includes a delta connected phase winding portion and a wye connected phase winding portion. Both the delta and wye connected phase winding portions have a thirty electrical degree phase belt width. The delta and wye connected phase winding portions are each formed from a preselected number of individual coils each formed, in turn, from an unequal number of electrical conductor turns in the approximate ratio of .sqroot.3. The individual coils of the delta and wye connected phase winding portions may either be connected in series or parallel. This arrangement provides an armature winding for a three phase motor which retains the benefits of the widely known and utilized thirty degree phase belt concept, including improved mmf waveform and fundamental distribution factor, with consequent reduced vibrations and improved efficiency.

Slavik, Charles J. (Rexford, NY); Rhudy, Ralph G. (Scotia, NY); Bushman, Ralph E. (Lathem, NY)

1997-01-01T23:59:59.000Z

142

Vibrated polar disks: spontaneous motion, binary collisions, and collective dynamics  

E-Print Network (OSTI)

We study the spontaneous motion, binary collisions, and collective dynamics of "polar disks", i.e. purpose-built particles which, when vibrated between two horizontal plates, move coherently along a direction strongly correlated to their intrinsic polarity. The motion of our particles, although nominally three-dimensional and complicated, is well accounted for by a two-dimensional persistent random walk. Their binary collisions are spatiotemporally extended events during which multiple actual collisions happen, yielding a weak average effective alignment. We show that this well-controlled, "dry active matter" system can display collective motion with orientationally-ordered regions of the order of the system size. We provide evidence of strong number density in the most ordered regimes observed. These results are discussed in the light of the limitations of our system, notably those due to the inevitable presence of walls.

Julien Deseigne; Sébastien Léonard; Olivier Dauchot; Hugues Chaté

2012-01-29T23:59:59.000Z

143

Downhole Vibration Monitoring & Control System  

SciTech Connect

The objective of this program is to develop a system to both monitor the vibration of a bottomhole assembly, and to adjust the properties of an active damper in response to these measured vibrations. Phase I of this program, which entailed modeling and design of the necessary subsystems and design, manufacture and test of a full laboratory prototype, was completed on May 31, 2004. The principal objectives of Phase II were: more extensive laboratory testing, including the evaluation of different feedback algorithms for control of the damper; design and manufacture of a field prototype system; and, testing of the field prototype in a drilling laboratory. Phase II concluded on January 31, 2006, and the Phase II final report was issued. Work on Phase III of the project began during the first quarter, 2006. Efforts the current quarter have continued to focus on the manufacture of the prototype and precommercial parts, field test planning and commercialization. The continued extreme lead times quoted by oilfield machine shops for collar components significantly delayed the deployment of the prototype and precommercial units. All parts have now been received for two units, and all but one for the third. Mechanical assembly of the first two systems is complete and the electronics installation and laboratory testing will be finished in April. We have entered into a Memorandum of Understanding with a major US oilfield equipment supplier, which calls for their assisting with our field tests, in cash and in kind. We are close to signing a definitive agreement which includes the purchase of the three precommercial units. We had also signed a CRADA with the Rocky Mountain Oilfield Test Center (RMOTC), and scheduled a test at their site, The RMOTC drilling schedule continues to slip, and the test cannot begin until the first week of May. Based on these factors, we have requested a no-cost extension to July 31, 2007.

Martin E. Cobern

2007-03-31T23:59:59.000Z

144

DOWNHOLE VIBRATION MONITORING & CONTROL SYSTEM  

SciTech Connect

The objective of this program is to develop a system to both monitor the vibration of a bottomhole assembly, and to adjust the properties of an active damper in response to these measured vibrations. Phase I of this program, which entailed modeling and design of the necessary subsystems and design, manufacture and test of a full laboratory prototype, was completed on May 31, 2004. The principal objectives of Phase II are: more extensive laboratory testing, including the evaluation of different feedback algorithms for control of the damper; design and manufacture of a field prototype system; and, testing of the field prototype in drilling laboratories and test wells. As a result of the lower than expected performance of the MR damper noted last quarter, several additional tests were conducted. These dealt with possible causes of the lack of dynamic range observed in the testing: additional damping from the oil in the Belleville springs; changes in properties of the MR fluid; and, residual magnetization of the valve components. Of these, only the last was found to be significant. By using a laboratory demagnetization apparatus between runs, a dynamic range of 10:1 was achieved for the damper, more than adequate to produce the needed improvements in drilling. Additional modeling was also performed to identify a method of increasing the magnetic field in the damper. As a result of the above, several changes were made in the design. Additional circuitry was added to demagnetize the valve as the field is lowered. The valve was located to above the Belleville springs to reduce the load placed upon it and offer a greater range of materials for its construction. In addition, to further increase the field strength, the coils were relocated from the mandrel to the outer housing. At the end of the quarter, the redesign was complete and new parts were on order. The project is approximately three months behind schedule at this time.

Martin E. Cobern

2005-04-27T23:59:59.000Z

145

Vibrations in brass instrument bodies: A review.  

Science Journals Connector (OSTI)

The bodies of brass instruments vibrate when played as evident to any player. These vibrations are driven mechanically at the player’s lips and by coupling with the internal acoustic field throughout the instrument. The coupling can equally well allow energy flow in the opposite direction from the body to the player’s lips and to the internal acoustic field. The vibrating shell can also radiate directly into the room. Studies involving human or machine players suggest that the effect of the wall vibrations on the acoustic spectral components is of the order of a few decibels. However for the most part the direct radiation of the wall vibrations is approximately 20 dB below the level of the radiated internal acoustic field. The wall vibrations have a slightly different time envelope though and also have a formant?like region around a few kilohertz. Some of the pieces of this complex puzzle that need further investigation include the interaction between player and instrument the effect of sound level on the coupling the perceptibility of the radiated vibrations by auditors and the variations within the brass family.

Peter L. Hoekje

2010-01-01T23:59:59.000Z

146

Multicoloured Random Graphs: The Random Dynamics Program  

E-Print Network (OSTI)

The Random Dynamics program is a proposal to explain the origin of all symmetries, including Lorentz and gauge invariance without appeal to any fundamental invariance of the laws of nature, and to derive the known physical laws in such a way as to be almost unavoidable. C. D. Froggatt and H. B. Nielsen proposed in their book Origin of Symmetries, that symmetries and physical laws should arise naturally from some essentially random dynamics rather than being postulated to be exact. The most useful assumption of the program that can be made about the fundamental laws is taken to be that they are random and then to see how known physics like mechanics and relativity follow from them. It is believed that almost any model of these regularities would appear in some limit for example as energies become small. Almost all theories or models at the fundamental level could then explain known physics. We suggest how using the formalism and properties of random graphs might be useful in developing the theory, and point towards directions in which it can be more fully extended in future work.

Sam Tarzi

2014-07-15T23:59:59.000Z

147

Windowed defocused photographic speckle vibration measurement  

E-Print Network (OSTI)

The out-of-plane vibration of a rough surface causes an in-plane vibration of its speckle pattern when observed with a defocused optical photographic system. If the frequency of the oscillations is high enough, a time-averaged specklegram is recorded from which the amplitude of the vibration can be estimated. The statistical character of speckle distributions along with the pixel sampling and intensity analog-to-digital conversion inherent to electronic cameras degrade the accuracy of the amplitude measurement to an extent that is analyzed and experimentally tested in this paper. The relations limiting the mutually competing metrological features of a defocused speckle system are also deduced mathematically.

Diazdelacruz, Jose M

2014-01-01T23:59:59.000Z

148

Vibration-Induced Climbing of Drops  

Science Journals Connector (OSTI)

We report an experimental study of liquid drops moving against gravity, when placed on a vertically vibrating inclined plate, which is partially wetted by the drop. The frequency of vibrations ranges from 30 to 200 Hz, and, above a threshold in vibration acceleration, drops experience an upward motion. We attribute this surprising motion to the deformations of the drop, as a consequence of an up or down symmetry breaking induced by the presence of the substrate. We relate the direction of motion to contact angle measurements. This phenomenon can be used to move a drop along an arbitrary path in a plane, without special surface treatments or localized forcing.

P. Brunet; J. Eggers; R. D. Deegan

2007-10-03T23:59:59.000Z

149

Microelectromechanical power generator and vibration sensor  

DOE Patents (OSTI)

A microelectromechanical (MEM) apparatus is disclosed which can be used to generate electrical power in response to an external source of vibrations, or to sense the vibrations and generate an electrical output voltage in response thereto. The MEM apparatus utilizes a meandering electrical pickup located near a shuttle which holds a plurality of permanent magnets. Upon movement of the shuttle in response to vibrations coupled thereto, the permanent magnets move in a direction substantially parallel to the meandering electrical pickup, and this generates a voltage across the meandering electrical pickup. The MEM apparatus can be fabricated by LIGA or micromachining.

Roesler, Alexander W. (Tijeras, NM); Christenson, Todd R. (Albuquerque, NM)

2006-11-28T23:59:59.000Z

150

2012 VIBRATIONAL SPECTROSCOPY GORDON RESEARCH CONFERENCE, AUGUST 5-10, 2012  

SciTech Connect

The Vibrational Spectroscopy conference brings together experimentalists and theoreticians working at the frontiers of modern vibrational spectroscopy, with a special emphasis on spectroscopies that probe the structure and dynamics of molecules in gases, liquids, and at interfaces. The conference explores the wide range of state-of-the-art techniques based on vibrational motion. These techniques span the fields of time-domain, high-resolution frequency-domain, spatially-resolved, nonlinear, and multidimensional spectroscopies. The conference highlights both the application of these techniques in chemistry, materials, biology, the environment, and medicine as well as the development of theoretical models that enable one to connect spectroscopic signatures to underlying molecular motions including chemical reaction dynamics. The conference goal is to advance the field of vibrational spectroscopy by bringing together a collection of researchers who share common interests and who will gain from discussing work at the forefront of several connected areas. The intent is to emphasize the insights and understanding that studies of vibrations provide about a variety of molecular systems ranging from small polyatomic molecules to large biomolecules, nanomaterials, and environmental systems.

Geiger, Franz

2012-08-10T23:59:59.000Z

151

Quantifiers for randomness of chaotic pseudo-random number generators  

Science Journals Connector (OSTI)

...randomness of chaotic pseudo-random number generators L. De Micco 1 H. A. Larrondo 1...connection with pseudo-random number generators (PRNGs). Workers in the field are...notion to generate pseudo-random number generators (PRNGs) because random numbers are...

2009-01-01T23:59:59.000Z

152

Roland Kruse, Tiedo Meyer: Vibration platform for the calibration of  

E-Print Network (OSTI)

Overview The project KOLOS Vibration sensor Measurement principle Vibration platform I Concept KOLOS (Cost-Effective Laser Sensor for Optical Vibration Measurements) · Low cost, contactless sensor for measuring the amplitude of in-plane vibrations · Based on the evaluation of the speckle pattern

Vormann, Matthias

153

Water distribution measurement in sand using sound vibration and SLDV  

E-Print Network (OSTI)

Water distribution measurement in sand using sound vibration and SLDV T. Sugimotoa , Y. Nakagawaa vibrator is used as a sound source. SLDV measures the vibration of ground surface. The propagation velocity between vibrator and measuring point is used to estimate the water distribution. Also, the soil

Boyer, Edmond

154

Piezoresistive and Piezoelectric MEMS Strain Sensors for Vibration Detection  

E-Print Network (OSTI)

Piezoresistive and Piezoelectric MEMS Strain Sensors for Vibration Detection Stanley Kona, Kenn and piezoelectric materials are commonly used to detect strain caused by structural vibrations in macro, vibration 1. INTRODUCTION Vibrations are a common phenomena of mechanical structures that can be detrimental

Horowitz, Roberto

155

Vibration?Rotation Spectroscopy of Molecules Trapped inside C60  

Science Journals Connector (OSTI)

The remaining six degrees of freedom correspond to the vibrations and rotations of the diatomic molecule and the rattling vibration of the molecule inside the cage. ... The vibrational frequency and the rotational constant are slightly different. ... Dimerization of I mediated by 4-aminopyridine in a high-speed vibrating mill yields the cyclobutane-contg. ...

R. James Cross

2008-07-04T23:59:59.000Z

156

SUSPENSION VIBRATION COMPENSATION USING A MEMS MICROACTUATOR IN HARD  

E-Print Network (OSTI)

SUSPENSION VIBRATION COMPENSATION USING A MEMS MICROACTUATOR IN HARD DISK DRIVES Tsung-Lin Chen of a prototype MEMS microactuator and vibration sensors, and controller design for suspension vibration. An LQG method is proposed for vibration sensor location and orientation optimization. Strain sensors

Horowitz, Roberto

157

Vibration Analysis of Wiresaw Manufacturing Processes and Wafer Surface Measurements  

E-Print Network (OSTI)

Vibration Analysis of Wiresaw Manufacturing Processes and Wafer Surface Measurements I. Kao (PI), S the yield per crystal and to reduce the cost. In this paper, the vibration model of wiresaw system of vibration indicate the interference of excitation and natural frequencies in the vibration patterns

Kao, Imin

158

PROOF-MASS INERTIAL VIBRATION CONTROL USING A SHUNTED  

E-Print Network (OSTI)

PROOF-MASS INERTIAL VIBRATION CONTROL USING A SHUNTED ELECTROMAGNETIC TRANSDUCER Andrew J. Fleming-mass dampers utilize a suspended mass to reduce the vibration experienced by a host structure. Active vibration vibration absorbtion. An electrical impedance is designed and connected to an electromagnetic coil

Fleming, Andrew J.

159

VIBRATIONALLY EXCITED HCN AROUND AFGL 2591: A PROBE OF PROTOSTELLAR STRUCTURE  

SciTech Connect

Vibrationally excited molecules with submillimeter rotational transitions are potentially excellent probes of physical conditions near protostars. This study uses observations of the v = 1 and v = 2 ro-vibrational modes of HCN (4-3) to probe this environment. The presence or absence and relative strengths of these ro-vibrational lines probe the gas excitation mechanism and physical conditions in warm, dense material associated with protostellar disks. We present pilot observations from the Heinrich Hertz Submillimeter Telescope and follow-up observations from the Submillimeter Array. All vibrationally excited HCN (4-3) v = 0, v = 1, and v = 2 lines were observed. The existence of the three v = 2 lines at approximately equal intensity imply collisional excitation with a density of greater than (10{sup 10} cm{sup -3}) and a temperature of >1000 K for the emitting gas. This warm, high-density material should directly trace structures formed in the protostellar envelope and disk environment. Further, the line shapes of the v = 2 emission may suggest a Keplerian disk. This Letter demonstrates the utility of this technique which is of particular interest due to the recent inauguration of the Atacama Large Millimeter Array.

Veach, Todd J. [Department of Physics, Arizona State University, Tempe, AZ 85287 (United States); Groppi, Christopher E. [School for Earth and Space Exploration, Arizona State University, Tempe, AZ 85287 (United States); Hedden, Abigail, E-mail: tveach@asu.edu [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, MS-78, Cambridge, MA 02138 (United States)

2013-03-10T23:59:59.000Z

160

A study of information dissemination under multiple random walkers and replication mechanisms  

Science Journals Connector (OSTI)

Random walk-based approaches are suitable for information dissemination in mobile and opportunistic environments that are inherently dynamic and typically large-scale. Multiple random walkers have been proposed in the recent past as a suitable ... Keywords: coverage, dissemination and replication techniques, multiple random walkers

Konstantinos Oikonomou; Dimitrios Kogias; Ioannis Stavrakakis

2010-02-01T23:59:59.000Z

Note: This page contains sample records for the topic "random vibration environment" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

Supine human response and vibration-suppression during whole-body vibration.  

E-Print Network (OSTI)

?? Whole-body vibration (WBV) has been identified as a stressor to supine patients with head and spinal injuries during medical transportation. Limited information is available… (more)

Meusch, John Carl

2012-01-01T23:59:59.000Z

162

Harmonic distortion reduction on seismic vibrators  

Science Journals Connector (OSTI)

...amplitude and phase in the fundamental frequency, resulting...accurate control of the fundamental component in the vibrator...a prime mover or a diesel engine to drive the pumps...and intensity of the fundamental force with model 364...

Zhouhong Wei; Thomas F. Phillips

163

Electrostatic vibration-to-electric energy conversion  

E-Print Network (OSTI)

Ultra-Low-Power electronics can perform useful functions with power levels as low as 170 nW. This makes them amenable to powering from ambient sources such as vibration. In this case, they can become autonomous. Motivated ...

Mur Miranda, José Oscar, 1972-

2004-01-01T23:59:59.000Z

164

Harmonic distortion reduction on seismic vibrators  

Science Journals Connector (OSTI)

...as well. However, in general, Figure 6 demonstrates...a prime mover or a diesel engine to drive the pumps...vibrator performance. In general, the coupling conditions...rocking motions. In general, the contact area becomes...

Zhouhong Wei; Thomas F. Phillips

165

Airfoil Vortex Induced Vibration suppression devices  

E-Print Network (OSTI)

Vortex Induced Vibrations (VIV) is a major concern of the offshore oil industry. This problem leads to fatigue failure in the marine risers and causes costly replacement of the risers. Appendages such as helical strakes ...

Lee, Evan J. (Evan Joseph)

2007-01-01T23:59:59.000Z

166

Journalaf Sound and Vibration (1997) 204(1), 131-158 VIBRATIONS OF OPEN-SECTION CHANNELS  

E-Print Network (OSTI)

Journalaf Sound and Vibration (1997) 204(1), 131-158 ·VIBRATIONS OF OPEN-SECTION CHANNELS 1997) An exact analytical method is presented for the analysis of forced vibrations of uniform, open the flexural and the torsional vibrations are coupled. In the context of this study, the type of any existing

Yaman, Yavuz

167

Method and apparatus for vibrating a substrate during material formation  

DOE Patents (OSTI)

A method and apparatus for affecting the properties of a material include vibrating the material during its formation (i.e., "surface sifting"). The method includes the steps of providing a material formation device and applying a plurality of vibrations to the material during formation, which vibrations are oscillations having dissimilar, non-harmonic frequencies and at least two different directions. The apparatus includes a plurality of vibration sources that impart vibrations to the material.

Bailey, Jeffrey A. (Richland, WA) [Richland, WA; Roger, Johnson N. (Richland, WA) [Richland, WA; John, Munley T. (Benton City, WA) [Benton City, WA; Walter, Park R. (Benton City, WA) [Benton City, WA

2008-10-21T23:59:59.000Z

168

Skyrmion vibration modes within the rational map ansatz  

SciTech Connect

We study the vibration modes of the Skyrme model within the rational map ansatz. We show that the vibrations of the radial profiles and the rational maps are decoupled and we consider explicitly the cases B=1, B=2, and B=4. We then compare our results with the vibration modes obtained numerically by Barnes et al. and show that qualitatively the rational map reproduces the vibration modes obtained numerically but that the vibration frequencies of these modes do not match very well.

Lin, W. T.; Piette, B. [Department of Mathematical Sciences, University of Durham, Durham, DH1 3LE (United Kingdom)

2008-06-15T23:59:59.000Z

169

Skyrmion Vibration Modes within the Rational Map Ansatz  

E-Print Network (OSTI)

We study the vibration modes of the Skyrme model within the rational map ansatz. We show that the vibrations of the radial profiles and the rational maps are decoupled and we consider explicitly the case B=1, B=2 and B=4. We then compare our results with the vibration modes obtained numerically by Barnes et al. and show that qualitatively the rational map reproduces the vibration modes obtained numerically but that the vibration frequencies of these modes do not match very well.

W. T. Lin; B. Piette

2008-04-30T23:59:59.000Z

170

Redesigned recycle valves abate compressor vibration  

SciTech Connect

New recycle valves installed in 1994 on the compressors in the East Brae field in the North Sea corrected the noise and vibration problem that damaged the original valves shortly after commissioning the platform. The original recycle valves, especially on the second-stage compressors, showed severe damage. The paper describes the Brae field, the recycle system, recycle valves, operations, the new valve design, noise and vibration, and valve actuators.

Laing, D.E. [Marathon Oil U.K. Ltd., Aberdeen (United Kingdom); Miller, H.L.; McCaskill, J.W. [Engineering Control Components Inc., Rancho Santa Margarita, CA (United States)

1995-06-05T23:59:59.000Z

171

Quantum random access memory  

E-Print Network (OSTI)

A random access memory (RAM) uses n bits to randomly address N=2^n distinct memory cells. A quantum random access memory (qRAM) uses n qubits to address any quantum superposition of N memory cells. We present an architecture that exponentially reduces the requirements for a memory call: O(log N) switches need be thrown instead of the N used in conventional (classical or quantum) RAM designs. This yields a more robust qRAM algorithm, as it in general requires entanglement among exponentially less gates, and leads to an exponential decrease in the power needed for addressing. A quantum optical implementation is presented.

Vittorio Giovannetti; Seth Lloyd; Lorenzo Maccone

2007-08-14T23:59:59.000Z

172

Electrostatic DFT Map for the Complete Vibrational Amide Band of NMA Tomoyuki Hayashi, Wei Zhuang, and Shaul Mukamel*  

E-Print Network (OSTI)

. Sampling the global electric field in the entire region of the transition charge densities (TCDs is a powerful tool for prob- ing molecular structure and dynamics in the condensed phase.1-13 Vibrational frequencies are sensitive to the local solvent environment; the frequency shift with respect to the gas phase

Mukamel, Shaul

173

Random multiparty entanglement distillation  

E-Print Network (OSTI)

We describe various results related to the random distillation of multiparty entangled states - that is, conversion of such states into entangled states shared between fewer parties, where those parties are not predetermined. In previous work [Phys. Rev. Lett. 98, 260501 (2007)] we showed that certain output states (namely Einstein-Podolsky-Rosen (EPR) pairs) could be reliably acquired from a prescribed initial multipartite state (namely the W state) via random distillation that could not be reliably created between predetermined parties. Here we provide a more rigorous definition of what constitutes ``advantageous'' random distillation. We show that random distillation is always advantageous for W-class three-qubit states (but only sometimes for Greenberger-Horne-Zeilinger (GHZ)-class states). We show that the general class of multiparty states known as symmetric Dicke states can be readily converted to many other states in the class via random distillation. Finally we show that random distillation is provably not advantageous in the limit of multiple copies of pure states.

Ben Fortescue; Hoi-Kwong Lo

2007-09-25T23:59:59.000Z

174

Random Testing versus Partition Testing.  

E-Print Network (OSTI)

?? The difference between Partition Testing and Random Testing has been thoroughlyinvestigated theoretically. In this thesis we present a practical study ofthe differences between random… (more)

Oftedal, Kristian

2011-01-01T23:59:59.000Z

175

Terahertz Vibration?Rotation?Tunneling Spectroscopy of the Ammonia Dimer. II. A?E States of an Out-of-Plane Vibration and an In-Plane Vibration  

Science Journals Connector (OSTI)

Terahertz Vibration?Rotation?Tunneling Spectroscopy of the Ammonia Dimer. ... In order to proceed toward the ultimate goal of determining an accurate intermolecular potential surface like what has been done for the water dimer, it is necessary to thoroughly characterize the intermolecular vibrations. ... The ab initio harmonic vibrational frequencies are known to be often too high for the weakly bound systems. ...

Wei Lin; Jia-xiang Han; Lynelle K. Takahashi; Jennifer G. Loeser; Richard J. Saykally

2007-09-07T23:59:59.000Z

176

A discrete fractional random transform  

E-Print Network (OSTI)

We propose a discrete fractional random transform based on a generalization of the discrete fractional Fourier transform with an intrinsic randomness. Such discrete fractional random transform inheres excellent mathematical properties of the fractional Fourier transform along with some fantastic features of its own. As a primary application, the discrete fractional random transform has been used for image encryption and decryption.

Zhengjun Liu; Haifa Zhao; Shutian Liu

2006-05-20T23:59:59.000Z

177

Ultrastable lasers based on vibration insensitive cavities  

SciTech Connect

We present two ultrastable lasers based on two vibration insensitive cavity designs, one with vertical optical axis geometry, the other horizontal. Ultrastable cavities are constructed with fused silica mirror substrates, shown to decrease the thermal noise limit, in order to improve the frequency stability over previous designs. Vibration sensitivity components measured are equal to or better than 1.5x10{sup -11}/m s{sup -2} for each spatial direction, which shows significant improvement over previous studies. We have tested the very low dependence on the position of the cavity support points, in order to establish that our designs eliminate the need for fine tuning to achieve extremely low vibration sensitivity. Relative frequency measurements show that at least one of the stabilized lasers has a stability better than 5.6x10{sup -16} at 1 s, which is the best result obtained for this length of cavity.

Millo, J.; Magalhaes, D. V.; Mandache, C.; Le Coq, Y.; English, E. M. L.; Westergaard, P. G.; Lodewyck, J.; Bize, S.; Lemonde, P.; Santarelli, G. [LNE-SYRTE, Observatoire de Paris, CNRS, UPMC, 61 Avenue de l'Observatoire, 75014 Paris (France)

2009-05-15T23:59:59.000Z

178

Mechanical vibration to electrical energy converter  

DOE Patents (OSTI)

Electromechanical devices that generate an electrical signal in response to an external source of mechanical vibrations can operate as a sensor of vibrations and as an energy harvester for converting mechanical vibration to electrical energy. The devices incorporate a magnet that is movable through a gap in a ferromagnetic circuit, wherein a coil is wound around a portion of the ferromagnetic circuit. A flexible coupling is used to attach the magnet to a frame for providing alignment of the magnet as it moves or oscillates through the gap in the ferromagnetic circuit. The motion of the magnet can be constrained to occur within a substantially linear range of magnetostatic force that develops due to the motion of the magnet. The devices can have ferromagnetic circuits with multiple arms, an array of magnets having alternating polarity and, encompass micro-electromechanical (MEM) devices.

Kellogg, Rick Allen (Tijeras, NM); Brotz, Jay Kristoffer (Albuquerque, NM)

2009-03-03T23:59:59.000Z

179

A study of low level vibrations as a power source for wireless sensor nodes  

Science Journals Connector (OSTI)

Advances in low power VLSI design, along with the potentially low duty cycle of wireless sensor nodes open up the possibility of powering small wireless computing devices from scavenged ambient power. A broad review of potential power scavenging technologies and conventional energy sources is first presented. Low-level vibrations occurring in common household and office environments as a potential power source are studied in depth. The goal of this paper is not to suggest that the conversion of vibrations is the best or most versatile method to scavenge ambient power, but to study its potential as a viable power source for applications where vibrations are present. Different conversion mechanisms are investigated and evaluated leading to specific optimized designs for both capacitive MicroElectroMechancial Systems (MEMS) and piezoelectric converters. Simulations show that the potential power density from piezoelectric conversion is significantly higher. Experiments using an off-the-shelf PZT piezoelectric bimorph verify the accuracy of the models for piezoelectric converters. A power density of 70 ?W/cm3 has been demonstrated with the PZT bimorph. Simulations show that an optimized design would be capable of 250 ?W/cm3 from a vibration source with an acceleration amplitude of 2.5 m/s2 at 120 Hz.

Shad Roundy; Paul K. Wright; Jan Rabaey

2003-01-01T23:59:59.000Z

180

Conformational and Vibrational Studies of Triclosan  

Science Journals Connector (OSTI)

The conformational equilibrium of triclosan (5?chloro?2?(2 4?dichlorophenoxy) phenol) have been calculated using density functional theory (DFTe/B3LYP/6?311++G(d p)) method. Four different geometries were found to correspond to energy minimum conformations. The IR spectrum of triclosan was measured in the 4000–400? cm ?1 region. We calculated the harmonic frequencies and intensities of the most stable conformers in order to assist in the assignment of the vibrational bands in the experimental spectrum. The fundamental vibrational modes were characterized depending on their total energy distribution (TED%) using scaled quantum mechanical (SQM) force field method.

Haci Özi?ik; S. Haman Bayari; Semran Sa?lam

2010-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "random vibration environment" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

Surrogate Spent Nuclear Fuel Vibration Integrity Investigation  

SciTech Connect

Transportation packages for spent nuclear fuel (SNF) must meet safety requirements under normal and accident conditions as specified by federal regulations. During transportation, SNF experiences unique conditions and challenges to cladding integrity due to the vibrational and impact loading encountered during road or rail shipment. ORNL has been developing testing capabilities that can be used to improve our understanding of the impacts of vibration loading on SNF integrity, especially for high burn-up SNF in normal transportation operation conditions. This information can be used to meet nuclear industry and U.S. Nuclear Regulatory Commission needs in the area of safety of SNF storage and transportation operations.

Wang, Jy-An John [ORNL; Wang, Hong [ORNL; Bevard, Bruce Balkcom [ORNL; Howard, Rob L [ORNL

2014-01-01T23:59:59.000Z

182

TEST SYSTEM FOR EVALUATING SPENT NUCLEAR FUEL BENDING STIFFNESS AND VIBRATION INTEGRITY  

SciTech Connect

Transportation packages for spent nuclear fuel (SNF) must meet safety requirements specified by federal regulations. For normal conditions of transport, vibration loads incident to transport must be considered. This is particularly relevant for high-burnup fuel (>45 GWd/MTU). As the burnup of the fuel increases, a number of changes occur that may affect the performance of the fuel and cladding in storage and during transportation. The mechanical properties of high-burnup de-fueled cladding have been previously studied by subjecting defueled cladding tubes to longitudinal (axial) tensile tests, ring-stretch tests, ring-compression tests, and biaxial tube burst tests. The objective of this study is to investigate the mechanical properties and behavior of both the cladding and the fuel in it under vibration/cyclic loads similar to the sustained vibration loads experienced during normal transport. The vibration loads to SNF rods during transportation can be characterized by dynamic, cyclic, bending loads. The transient vibration signals in a specified transport environment can be analyzed, and frequency, amplitude and phase components can be identified. The methodology being implemented is a novel approach to study the vibration integrity of actual SNF rod segments through testing and evaluating the fatigue performance of SNF rods at defined frequencies. Oak Ridge National Laboratory (ORNL) has developed a bending fatigue system to evaluate the response of the SNF rods to vibration loads. A three-point deflection measurement technique using linear variable differential transformers is used to characterize the bending rod curvature, and electromagnetic force linear motors are used as the driving system for mechanical loading. ORNL plans to use the test system in a hot cell for SNF vibration testing on high burnup, irradiated fuel to evaluate the pellet-clad interaction and bonding on the effective lifetime of fuel-clad structure bending fatigue performance. Technical challenges include pure bending implementation, remote installation and detachment of the SNF test specimen, test specimen deformation measurement, and identification of a driving system suitable for use in a hot cell. Surrogate test specimens have been used to calibrate the test setup and conduct systematic cyclic tests. The calibration and systematic cyclic tests have been used to identify test protocol issues prior to implementation in the hot cell. In addition, cyclic hardening in unidirectional bending and softening in reverse bending were observed in the surrogate test specimens. The interface bonding between the surrogate clad and pellets was found to impact the bending response of the surrogate rods; confirming this behavior in the actual spent fuel segments will be an important aspect of the hot cell test implementation,

Wang, Jy-An John [ORNL] [ORNL; Wang, Hong [ORNL] [ORNL; Bevard, Bruce Balkcom [ORNL] [ORNL; Howard, Rob L [ORNL] [ORNL; Flanagan, Michelle [U.S. Nuclear Regulatory Commission] [U.S. Nuclear Regulatory Commission

2013-01-01T23:59:59.000Z

183

Tactile Icon Design Using a Vibration Actuator in Mobile Devices  

Science Journals Connector (OSTI)

This study presents three attributes for composing vibration patterns: Rhythm, intensity difference, and continuous variation in intensity. The intervals and the duration of the vibrations offer the elements of r...

Meng-Dar Shieh; Zheng-Bin Wu

2008-01-01T23:59:59.000Z

184

Apparatus and method of preloading vibration-damping bellows  

DOE Patents (OSTI)

An improved vibration damping bellows mount or interconnection is disclosed. In one aspect, the bellows is compressively prestressed along its length to offset vacuum-generated tensile loads and thereby improve vibration damping characteristics.

Cutburth, Ronald W. (Tracy, CA)

1988-01-01T23:59:59.000Z

185

Whole body vibration alters proprioception in the trunk  

E-Print Network (OSTI)

Occupational whole body vibration has long been associated with low back injuries. However, the mechanism of these injuries is not well understood. In this paper, the effect of whole body vibration on proprioception and dynamic stability...

Li, Lu; Lamis, Farhana; Wilson, Sara E.

2008-01-01T23:59:59.000Z

186

High-speed digital holographic interferometry for vibration measurement  

Science Journals Connector (OSTI)

A system based on digital holographic interferometry for the measurement of vibrations is presented. A high-power continuous laser

Pedrini, Giancarlo; Osten, Wolfgang; Gusev, Mikhail E

2006-01-01T23:59:59.000Z

187

An investigation of online environments supporting follow-up to professional development for Texas school librarians  

E-Print Network (OSTI)

-only control group experimental design with self-selected participants. School librarians were stratified by level of service and socioeconomic school status and were randomly assigned to one of three environments. Two experimental environments were used: (a...

Green, Mary Elizabeth

2006-04-12T23:59:59.000Z

188

VIBRATION AMPLITUDE -DEPENDENT NATURAL FREQUENCY AND DAMPING RATIO OF REPAIRED PIER MODEL  

E-Print Network (OSTI)

by measuring its vibration. Therefore, so far, vibration measurements have been carried out to various bridge of vibration can be verified by this method, in some cases, vibration measurement of existing bridges of vibration measurement methods without the need of vibration devices were founded [8]. The main purpose

Paris-Sud XI, Université de

189

Experimental Study of Active Vibration Control of a Cantilever Beam  

Science Journals Connector (OSTI)

The modern technology demands the system to be light and reliable. However, with the conventional vibration control techniques it is difficult to keep the system light with all the damping mechanisms. This work deals with the Active Vibration Control ... Keywords: Active Vibration Control, cantilever, classical controller, piezoelectric transducers

S. M. Khot, Nitesh P. Yelve, Shoaib Shaik

2013-12-01T23:59:59.000Z

190

POLE ASSIGNMENT FOR A VIBRATING SYSTEM WITH AERODYNAMIC EFFECT #  

E-Print Network (OSTI)

POLE ASSIGNMENT FOR A VIBRATING SYSTEM WITH AERODYNAMIC EFFECT # J. N. WANG + , S. H. CHOU # , Y. C­input state feedback control arising from a one­dimensional vibrating system with aerodynamic e real axis. Key words. vibrating system, aerodynamic e#ect, state feedback control, pole assignment AMS

Chou, So-Hsiang

191

POLE ASSIGNMENT FOR A VIBRATING SYSTEM WITH AERODYNAMIC EFFECT  

E-Print Network (OSTI)

POLE ASSIGNMENT FOR A VIBRATING SYSTEM WITH AERODYNAMIC EFFECT J. N. WANG, S. H. CHOU, Y. C. CHEN feedback control arising from a one-dimensional vibrating system with aerodynamic effect. On the practical real axis. Key words. vibrating system, aerodynamic effect, state feedback control, pole assignment AMS

Lin, Wen-Wei

192

Active Automobile Engine Vibration Analysis Technical Report Number 1  

E-Print Network (OSTI)

Active Automobile Engine Vibration Analysis Technical Report Number 1 Page 1 of 26 DISTRIBUTION STATEMENT: Distribution authorized to all. Active Automobile Engine Vibration Analysis Technical Report at the University of Southern California #12;Active Automobile Engine Vibration Analysis Technical Report Number 1

Levi, Anthony F. J.

193

Particle Sizing using Passive Ultrasonic Measurement of Vessel Wall Vibrations  

E-Print Network (OSTI)

Particle Sizing using Passive Ultrasonic Measurement of Vessel Wall Vibrations Gillian Carson for particle sizing using an ultrasonic transducer to measure vessel wall vibrations and 1 #12;considers in a stirred vessel, its subse- quent impact with the vessel wall, and the resulting flexural vibrations

Mottram, Nigel

194

LINEAR COLLIDER FINAL DOUBLET CONSIDERATIONS: ATF2 VIBRATION MEASUREMENTS*  

E-Print Network (OSTI)

LINEAR COLLIDER FINAL DOUBLET CONSIDERATIONS: ATF2 VIBRATION MEASUREMENTS* B. Bolzon# , N. Geffroy to measure medium frequency vibrations in vertical axis. First, ground motion was measured for 72 hours vibrations (with their supports) were measured to evaluate their rigidity. The correlation of QD0 and QF1

Paris-Sud XI, Université de

195

ACTIVE VIBRATION CONTROL OF A SMART BEAM Yavuz Yaman1  

E-Print Network (OSTI)

1 ACTIVE VIBRATION CONTROL OF A SMART BEAM Yavuz Yaman1 , Tarkan Ã?alikan1 , Volkan Nalbantolu2, Collingwood, Ontario, Canada ABSTRACT This study presents an active vibration control technique applied this reduced model, presents the design of an active vibration controller which effectively suppresses

Yaman, Yavuz

196

Vibration-Rotation Bands of Allene-1. 1-d$_{2}$  

Science Journals Connector (OSTI)

24 February 1959 research-article Vibration-Rotation Bands of Allene-1. 1-d...the perpendicular bands to particular vibrations, some characteristic details of their...Coriolis interaction between B and B class vibrations, and the results are in general accord...

1959-01-01T23:59:59.000Z

197

Vibration-Rotation Bands of Acetylene and the Molecular Dimensions  

Science Journals Connector (OSTI)

4 December 1956 research-article Vibration-Rotation Bands of Acetylene and the...constants in the isotopic acetylenes, some vibration-rotation bands of acetylene have been...The values for each of the molecular vibrations have been re-determined, taking into...

1956-01-01T23:59:59.000Z

198

Vibration–mediated interactions in a host–parasitoid system  

Science Journals Connector (OSTI)

22 February 1997 research-article Vibration-mediated interactions in a host-parasitoid...was to obtain behavioral evidence of vibration mediated interactions between the apple...their respective responses to the leaf vibrations produced by the other party. We analysed...

1997-01-01T23:59:59.000Z

199

THE VIBRATION OF A CONDUCTING WIRE IN A MAGNETIC FIELD  

Science Journals Connector (OSTI)

......1963 research-article Articles THE VIBRATION OF A CONDUCTING WIRE IN A MAGNETIC FIELD...Polytechnic Institute of Brooklyn. The vibration of a perfectly flexible, stretched...inpedance of the wire is discuassed. THE VIBRATION OF A CONDUCTING WIRE IN A MAGNETIC FIELD......

M.A. LEIBOWITZ; R.C. ACKERBERG

1963-11-01T23:59:59.000Z

200

Vibration of spinning discs and powder formation in centrifugal atomization  

Science Journals Connector (OSTI)

...research-article Research articles 1006 121 117 Vibration of spinning discs and powder formation...liquid film. In this paper, the vibration of an atomizing disc excited by...melt is analysed and the role of vibration in the disintegration of the melt...

2011-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "random vibration environment" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Vibration Control of Multi-Mode Rotor-Bearing Systems  

Science Journals Connector (OSTI)

8 March 1983 research-article Vibration Control of Multi-Mode Rotor-Bearing...least-squares method to minimize the vibration of any general rotor-bearing system...to implement the open-loop adaptive vibration control strategies outlined in the paper...

1983-01-01T23:59:59.000Z

202

Titel des Moduls : Geruschbekmpfung/ Noise and Vibration Control  

E-Print Network (OSTI)

Titel des Moduls : Geräuschbekämpfung/ Noise and Vibration Control LP (nach ECTS): 6 Interne Kurzbe) Pflicht(P) / Wahl(W) Wahlpflicht(WP) Semester (WiSe/SoSe) Noise & Vibration Control VL 2 3 WP Wi. Springer-Verlag Berlin. ISBN 3-540-54473-9. 2. L.L. Beranek (ed.), 1971. Noise and Vibration Control. Mc

Berlin,Technische Universität

203

Variational Structure of Inverse Problems in Wave Propagation and Vibration  

E-Print Network (OSTI)

Variational Structure of Inverse Problems in Wave Propagation and Vibration James G. Berryman in wave propagation (traveltime tomography) and two examples in vibration (the plucked string and free.'' For vibrating systems, the apparently very complex behavior of an excited string, drumhead, or the Earth can

204

Vibration Proof Construction of 1000kV Electron Microscope  

Science Journals Connector (OSTI)

......University Press 1970 other ORIGINAL Vibration Proof Construction of 1000kV Electron...with the center of gravity. That is, a vibration proof hanging console was made as a method...protecting a 1000kV Electron Microscope from vibration, and this allowed the whole instrument......

Yoshio SAKITANI; Susumu OZASA

1970-01-01T23:59:59.000Z

205

Vibration-Assisted Electron Tunneling in C140 Transistors  

Science Journals Connector (OSTI)

Vibration-Assisted Electron Tunneling in C140 Transistors ... When electrons travel through molecules, vibrational modes of the molecules can affect current flow. ... 1 Recently, effects of vibrations in single molecules have been measured using scanning tunneling microscopes,2 single-molecule transistors,3,4 and mechanical break junctions. ...

A. N. Pasupathy; J. Park; C. Chang; A. V. Soldatov; S. Lebedkin; R. C. Bialczak; J. E. Grose; L. A. K. Donev; J. P. Sethna; D. C. Ralph; P. L. McEuen

2005-01-07T23:59:59.000Z

206

Development of Flexural Vibration Inspection Techniques to Rapidly  

E-Print Network (OSTI)

Development of Flexural Vibration Inspection Techniques to Rapidly Assess the Structural Health conditions at supports #12;Phase II Activities !! Develop an automated testing system !! Conduct vibration testing on bridge sections during construction !! Conduct load and vibration testing of in-service spike

Minnesota, University of

207

Active Vibration Suppression of a Smart Beam Cem ONAT+,*  

E-Print Network (OSTI)

1 Active Vibration Suppression of a Smart Beam via PI Dµ Control Cem ONAT+,* , Melin SAHIN* , Yavuz controller was designed for the active vibration suppression of a smart beam equipped with PZT (Lead successfully suppressed the vibration levels of the smart beam for the first two flexural modes. Keywords

Yaman, Yavuz

208

Vibration-Free Pulse Tube Cryocooler System for Gravitational Wave Detectors, Part I: Vibration-Reduction Method and Measurement  

Science Journals Connector (OSTI)

We developed a vibration-free cryocooler system based on a 4 K pulse tube (PT) cryocooler for a cryogenic interferometric gravitational wave detector. In this system, we incorporated a vibration-reduction syst...

T. Tomaru; T. Suzuki; T. Haruyama; T. Shintomi; N. Sato; A. Yamamoto…

2005-01-01T23:59:59.000Z

209

HYDROGEN LOCAL VIBRATIONAL MODES IN COMPOUND SEMICONDUCTORS  

E-Print Network (OSTI)

HYDROGEN LOCAL VIBRATIONAL MODES IN COMPOUND SEMICONDUCTORS M.D. MCCLUSKEY* University) spectroscopy of hydrogen and deuterium in GaP, AlSb, ZnSe, and GaN has provided important information about the structures of dopant- hydrogen complexes and their interaction with the host lattice. In GaN:Mg, for example

McCluskey, Matthew

210

Noise and Vibration Reduction in Felt Mountings  

Science Journals Connector (OSTI)

Resonant curves of loaded felt pads in compressional vibration give values for the damping and dynamic stiffness which show that felt in vibration is quite different from an equivalent perfect spring with viscous damping. The un?symmetrical resonance curves and the fact that within experimental error the stiffness is inversely proportional to the square root of the thickness indicate a decrease in stiffness with increasing amplitude. The increase in stiffness with pressure is so large that the ratio of dynamic elastic modulus to pressure (stiffness over mass) does not vary greatly between pressures of three to one hundred pounds per square inch. In this range the natural frequency of a mass on a felt pad is determined by the thickness of the pad rather than by its area and static load. An analysis of the performance of felt in reducing vibration transmission shows that its effectiveness is limited in most cases to frequencies above forty cycles per second. Practical installations have been studied and tables drawn up to give the acoustical engineer “handbook” information for the solution of problems in vibration reduction.

H. C. Hardy; F. G. Tyzzer

1946-01-01T23:59:59.000Z

211

Vibrational and Ghost-Vibrational Resonances in A Modified Chua's Circuit Model Equation  

E-Print Network (OSTI)

The role of the number of breakpoints $N$ in the sawtooth form of the characteristic function in the modified Chua's circuit model equation on vibrational and ghost-vibrational resonances is investigated in this paper. To observe vibrational resonance the system should be driven by two periodic forces of frequencies $\\omega$ and $\\Omega$, with $\\Omega\\gg\\omega$. Resonance occurs at the frequency $\\omega$ when the amplitude of the high-frequency force is varied. When the system is subjected to an input signal containing multi-frequencies which are higher-order of a certain (missing) fundamental frequency, then a resonance at the missing fundamental frequency is induced by the high-frequency input signal and is called ghost-vibrational resonance. In both types of resonances, the number of resonances is $N$ and hysteresis occurs in each resonance region. There are some similarities and differences in these two resonance phenomena. We report in detail the influence of the role of number of breakpoints $N$ on the features of vibrational and ghost-vibrational resonances.

K. Abirami; S. Rajasekar; M. A. F. Sanjuan

2014-06-26T23:59:59.000Z

212

Downhole Vibration Monitoring and Control System  

SciTech Connect

The objective of this program is to develop a system to both monitor the vibration of a bottomhole assembly, and to adjust the properties of an active damper in response to these measured vibrations. The key feature of this system is its use of a magnetorheological fluid (MRF) to allow the damping coefficient to be changed extensively, rapidly and reversibly without the use of mechanical valves, but only by the application of a current. Phase I of this program, which entailed modeling and design of the necessary subsystems and design, manufacture and test of a full laboratory prototype, was completed on May 31, 2004. Much of the effort was devoted to the design and testing of the MRF damper, itself. The principal objectives of Phase II were: more extensive laboratory testing, including the evaluation of different feedback algorithms for control of the damper; design and manufacture of a field prototype system; and, testing of the field prototype in a drilling laboratory. Phase II concluded on January 31, 2006, and a final report was issued. Work on Phase III of the project began during the first quarter, 2006, with the objectives of building precommercial prototypes, testing them in a drilling laboratory and the field; developing and implementing a commercialization plan. All of these have been accomplished. The Downhole Vibration Monitoring & Control System (DVMCS) prototypes have been successfully proven in testing at the TerraTek drilling facility and at the Rocky Mountain Oilfield Test Center (RMOTC.) Based on the results of these tests, we have signed a definitive development and distribution agreement with Smith, and commercial deployment is underway. This current version of the DVMCS monitors and controls axial vibrations. Due to time and budget constraints of this program, it was not possible to complete a system that would also deal with lateral and torsional (stick-slip) vibrations as originally planned; however, this effort is continuing without DOE funding.

Martin E. Cobern

2007-09-30T23:59:59.000Z

213

The photodissociation and reaction dynamics of vibrationally excited molecules  

SciTech Connect

This research determines the nature of highly vibrationally excited molecules, their unimolecular reactions, and their photodissociation dynamics. The goal is to characterize vibrationally excited molecules and to exploit that understanding to discover and control their chemical pathways. Most recently the author has used a combination of vibrational overtone excitation and laser induced fluorescence both to characterize vibrationally excited molecules and to study their photodissociation dynamics. The author has also begun laser induced grating spectroscopy experiments designed to obtain the electronic absorption spectra of highly vibrationally excited molecules.

Crim, F.F. [Univ. of Wisconsin, Madison (United States)

1993-12-01T23:59:59.000Z

214

Statistics of power injection in a plate set into chaotic vibration  

E-Print Network (OSTI)

A vibrating plate is set into a chaotic state of wave turbulence by either a periodic or a random local forcing. Correlations between the forcing and the local velocity response of the plate at the forcing point are studied. Statistical models with fairly good agreement with the experiments are proposed for each forcing. Both distributions of injected power have a logarithmic cusp for zero power, while the tails are Gaussian for the periodic driving and exponential for the random one. The distributions of injected work over long time intervals are investigated in the framework of the fluctuation theorem, also known as the Gallavotti-Cohen theorem. It appears that the conclusions of the theorem are verified only for the periodic, deterministic forcing. Using independent estimates of the phase space contraction, this result is discussed in the light of available theoretical framework.

Olivier Cadot; Arezki Boudaoud; Cyril Touzé

2008-10-06T23:59:59.000Z

215

Adjustable Nonlinear Springs to Improve Efficiency of Vibration Energy Harvesters  

E-Print Network (OSTI)

Vibration Energy Harvesting is an emerging technology aimed at turning mechanical energy from vibrations into electricity to power microsystems of the future. Most of present vibration energy harvesters are based on a mass spring structure introducing a resonance phenomenon that allows to increase the output power compared to non-resonant systems, but limits the working frequency bandwidth. Therefore, they are not able to harvest energy when ambient vibrations' frequencies shift. To follow shifts of ambient vibration frequencies and to increase the frequency band where energy can be harvested, one solution consists in using nonlinear springs. We present in this paper a model of adjustable nonlinear springs (H-shaped springs) and their benefits to improve velocity-damped vibration energy harvesters' (VEH) output powers. A simulation on a real vibration source proves that the output power can be higher in nonlinear devices compared to linear systems (up to +48%).

S. Boisseau; G. Despesse; B. Ahmed Seddik

2012-07-19T23:59:59.000Z

216

Vibration?Pseudorotation Coupling in Symmetric Triatomic Molecules  

Science Journals Connector (OSTI)

For each type of molecule, the vibration?rotation coupling energy and vibrational structures of wave functions were examined up to the levels of high energy, about 15?000?20?000 cm-1 above the bottom of the well. ... The dynamics of polyatomic vibrations and vibration?rotation interaction in highly excited states have been the subject of many theoretical and experimental studies for the past decade. ... 11-13 Since the angular momentum of the system can also be generated by simultaneous vibrations as well as rotation of the molecule, there exists a coupling between vibration and rotation even for the states with zero total angular momentum (J = 0) which would be nonnegligible in some highly excited vibrational levels. ...

Jae Shin Lee

1996-02-01T23:59:59.000Z

217

Vibrational dynamics in isotopically substituted vitreous GeO2  

Science Journals Connector (OSTI)

We report the polarized Raman spectra of vitreous Ge O216, Ge O218, Ge70O2, and Ge74O2. This yields the O16?O18 and Ge70?Ge74 isotopic shifts for nearly all vibrational modes of the pure glassy material. The shifts of the broad high-frequency (infrared-active) modes are as predicted by a nearest-neighbor central-force ideal continuous—random-network model. The shift of the broad dominant Raman line indicates a small but significant dependence on the Ge mass, and this suggests an effect of disorder not included in the central-force theory. The narrow "defect" line at 530 cm-1 appears to be all oxygen motion, and is tentatively identified with a regular ring of bonds. The narrow line at 345 cm-1 is unique in that it exhibits very little oxygen shift; it seems to consist largely of Ge motion, for which we have no firm explanation.

F. L. Galeener; A. E. Geissberger; G. W. Ogar; Jr.; R. E. Loehman

1983-10-15T23:59:59.000Z

218

Vibration welding system with thin film sensor  

DOE Patents (OSTI)

A vibration welding system includes an anvil, a welding horn, a thin film sensor, and a process controller. The anvil and horn include working surfaces that contact a work piece during the welding process. The sensor measures a control value at the working surface. The measured control value is transmitted to the controller, which controls the system in part using the measured control value. The thin film sensor may include a plurality of thermopiles and thermocouples which collectively measure temperature and heat flux at the working surface. A method includes providing a welder device with a slot adjacent to a working surface of the welder device, inserting the thin film sensor into the slot, and using the sensor to measure a control value at the working surface. A process controller then controls the vibration welding system in part using the measured control value.

Cai, Wayne W; Abell, Jeffrey A; Li, Xiaochun; Choi, Hongseok; Zhao, Jingzhou

2014-03-18T23:59:59.000Z

219

Automatic monitoring of vibration welding equipment  

DOE Patents (OSTI)

A vibration welding system includes vibration welding equipment having a welding horn and anvil, a host device, a check station, and a robot. The robot moves the horn and anvil via an arm to the check station. Sensors, e.g., temperature sensors, are positioned with respect to the welding equipment. Additional sensors are positioned with respect to the check station, including a pressure-sensitive array. The host device, which monitors a condition of the welding equipment, measures signals via the sensors positioned with respect to the welding equipment when the horn is actively forming a weld. The robot moves the horn and anvil to the check station, activates the check station sensors at the check station, and determines a condition of the welding equipment by processing the received signals. Acoustic, force, temperature, displacement, amplitude, and/or attitude/gyroscopic sensors may be used.

Spicer, John Patrick; Chakraborty, Debejyo; Wincek, Michael Anthony; Wang, Hui; Abell, Jeffrey A; Bracey, Jennifer; Cai, Wayne W

2014-10-14T23:59:59.000Z

220

Active vibration control of civil structures  

SciTech Connect

This is a final report of a one year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). Active vibration control (AVC) of structural and mechanical systems is one of the rapidly advancing areas of engineering research. The multifaceted nature of AVC covers many disciplines, such as sensors and instrumentation, numerical modeling, experimental mechanics, and advanced power systems. This work encompassed a review of the literature on active control of structures focusing both on active control hardware and on control algorithms, a design of an isolation systems using magneto-rheological fluid-filled (MRF) dampers and numerical simulations to study the enhanced vibration mitigation effects of this technology.

Farrar, C.; Baker, W.; Fales, J.; Shevitz, D.

1996-11-01T23:59:59.000Z

Note: This page contains sample records for the topic "random vibration environment" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Vibration of submillimeter-size supported droplets  

Science Journals Connector (OSTI)

We study the fundamental vibration mode of supported submillimeter-size droplets. Using an analogy with a simple oscillator we derive a semianalytical expression for the eigenfrequency and the scaling law of the energy dissipation within the droplet. The experimental results obtained for mercury drops deposited on glass are compared with the model. The agreement is satisfactory for the eigenfrequencies on the whole range of size we considered (from 0.04 to 0.9mm). The scaling law for the dissipation is recovered for radii larger than 0.1mm but fails for smaller droplets. We finally discuss possible applications related to the use of vibrations to effectively reduce the hysteresis of the wetting angle and therefore increase the mobility of the supported droplets.

Franck Celestini and Richard Kofman

2006-04-07T23:59:59.000Z

222

Vibrational Superposition States Without Rotating Wave Approximation  

E-Print Network (OSTI)

We propose a scheme to generate superpositions of coherent states for the vibrational motion of a laser cooled trapped-ion. It is based on the interaction with a standing wave making use of the counter-rotating terms, i.e. not applying the rotating wave approximation. We also show that the same scheme can be exploited for quantum state measurement, i.e. with the same scheme non-classical states may be reconstructed

Mancini, S; Tombesi, P

2000-01-01T23:59:59.000Z

223

Vibrational sum frequency study on biological interfaces  

E-Print Network (OSTI)

) ............................................................................................................. 11 3 Vibrating capacitive probe ................................................................................. 16 4 Molecular structure of human plasma fibrinogen (FRN)................................... 19 5 Displacement of Alexa 594...-labeled fibrinogen from a silica surface by a 5% human plasma solution ............................................................ 24 6 AFM images of a single FRN molecule adsorbed at the silica/buffer interface (a) at pH 8.0 and (b) at pH 8.0 after...

Lim, Soon Mi

2009-06-02T23:59:59.000Z

224

Vibrational States of the Hydrogen Molecular Ion  

Science Journals Connector (OSTI)

The eigenvalues and eigenfunctions of the vibrational states belonging to the ground electronic state of the hydrogen molecular ion have been calculated. The calculations have been done for the J=0, 2, 4, and 7 rotational states. Included is a discussion of the dependence of the eigenvalues as a function of the lowest-order dynamic corrections to the internuclear potential. Also, a calculation has been done to determine the number of bound states of the D2+ system.

Stanley Cohen, John R. Hiskes, and Robert J. Riddell, Jr.

1960-08-01T23:59:59.000Z

225

Vibrations of Sessile Drops of Soft Hydrogels  

E-Print Network (OSTI)

Sessile drops of soft hydrogels were vibrated vertically by subjecting them to a mechanically induced Gaussian white noise. Power spectra of the surface fluctuation of the gel allowed identification of its resonant frequency that decreases with their mass, but increases with its shear modulus. The principal resonant frequencies of the spheroidal modes of the gel of shear moduli ranging from 55 Pa to 290 Pa were closest to the lowest Rayleigh mode of vibration of a drop of pure water. These observations coupled with the fact that the resonance frequency varies inversely as the square root of the mass in all cases suggest that they primarily correspond to the capillary (or a pseudo-capillary) mode of drop vibration. The contact angles of the gel drops also increase with the modulus of the gel. When the resonance frequencies are corrected for the wetting angles, and plotted against the fundamental frequency scale (gamma/mu)^0.5, all the data collapse nicely on a single plot provided that the latter is shifted by a shear modulus dependent factor (1+mu.L/gamma). A length scale L, independent of both the modulus and the mass of the drop emerges from such a fit.

Aditi Chakrabarti; Manoj K. Chaudhury

2014-10-08T23:59:59.000Z

226

Theoretical rotation-vibration spectrum of thioformaldehyde  

SciTech Connect

We present a variational calculation of the first comprehensive T = 300 K rovibrational line list for thioformaldehyde, H{sub 2}CS. It covers 41?809 rovibrational levels for states up to J{sub max} = 30 with vibrational band origins up to 5000 cm{sup ?1} and provides the energies and line intensities for 547?926 transitions from the ground vibrational state to these levels. It is based on our previously reported accurate ab initio potential energy surface and a newly calculated ab initio dipole moment surface. Minor empirical adjustments are made to the ab initio equilibrium geometry to reduce systematic errors in the predicted intra-band rotational energy levels. The rovibrational energy levels and transition intensities are computed variationally by using the methods implemented in the computer program TROVE. Transition wavelengths and intensities are found to be in excellent agreement with the available experimental data. The present calculations correctly reproduce the observed resonance effects, such as intensity borrowing, thus reflecting the high accuracy of the underlying ab initio surfaces. We report a detailed analysis of several vibrational bands, especially those complicated by strong Coriolis coupling, to facilitate future laboratory assignments.

Yachmenev, Andrey [Department of Physics and Astronomy, University College London, London, WC1E 6BT (United Kingdom)] [Department of Physics and Astronomy, University College London, London, WC1E 6BT (United Kingdom); Polyak, Iakov; Thiel, Walter [Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, D–45470 Mülheim an der Ruhr (Germany)] [Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, D–45470 Mülheim an der Ruhr (Germany)

2013-11-28T23:59:59.000Z

227

Randomly coupled Ising models  

Science Journals Connector (OSTI)

We consider the phase diagram of two randomly coupled Ising models to mimic the successive phase transitions in plastic crystals. Detailed mean-field calculations are performed. Depending on the strength of the couplings, the phase diagrams display three ordered phases and some multicritical points. A tetracritical point is found to turn bicritical as the strength of the couplings increases. The nature of this multicritical point is then analyzed by means of a momentum-space renormalization-group calculation. Using the replica trick, we obtain an effective n-component spin Hamiltonian. The random coupling is found to be relevant and shown to have drastic effects on the multicritical behavior. The lower critical dimension is estimated to be dl=2. In the n=0 limit, to first order in the parameter ?=4-d, a system of seven recursion relations is obtained. Although there is a stable fixed point, it cannot be reached from physically acceptable initial conditions. We give arguments to support a runaway of the flow lines associated with a fluctuation-induced first-order transition.

S. Galam; S. R. Salinas; Y. Shapir

1995-02-01T23:59:59.000Z

228

Accelerated Randomized Benchmarking  

E-Print Network (OSTI)

Quantum information processing offers promising advances for a wide range of fields and applications, provided that we can efficiently assess the performance of the control applied in candidate systems. That is, we must be able to determine whether we have implemented a desired gate, and refine accordingly. Randomized benchmarking reduces the difficulty of this task by exploiting symmetries in quantum operations. Here, we bound the resources required for benchmarking and show that, with prior information, we can achieve several orders of magnitude better accuracy than in traditional approaches to benchmarking. Moreover, by building on state-of-the-art classical algorithms, we reach these accuracies with near-optimal resources. Our approach requires an order of magnitude less data to achieve the same accuracies and to provide online estimates of the errors in the reported fidelities. We also show that our approach is useful for physical devices by comparing to simulations. Our results thus enable the application of randomized benchmarking in new regimes, and dramatically reduce the experimental effort required to assess control fidelities in quantum systems. Finally, our work is based on open-source scientific libraries, and can readily be applied in systems of interest.

Christopher Granade; Christopher Ferrie; D. G. Cory

2014-04-21T23:59:59.000Z

229

A Vibrating Wire System For Quadrupole Fiducialization  

SciTech Connect

A vibrating wire system is being developed to fiducialize the quadrupoles between undulator segments in the LCLS. This note provides a detailed analysis of the system. The LCLS will have quadrupoles between the undulator segments to keep the electron beam focused. If the quadrupoles are not centered on the beam axis, the beam will receive transverse kicks, causing it to deviate from the undulator axis. Beam based alignment will be used to move the quadrupoles onto a straight line, but an initial, conventional alignment must place the quadrupole centers on a straight line to 100 {micro}m. In the fiducialization step of the initial alignment, the position of the center of the quadrupole is measured relative to tooling balls on the outside of the quadrupole. The alignment crews then use the tooling balls to place the magnet in the tunnel. The required error on the location of the quadrupole center relative to the tooling balls must be less than 25 {micro}m. In this note, we analyze a system under construction for the quadrupole fiducialization. The system uses the vibrating wire technique to position a wire onto the quadrupole magnetic axis. The wire position is then related to tooling balls using wire position detectors. The tooling balls on the wire position detectors are finally related to tooling balls on the quadrupole to perform the fiducialization. The total 25 {micro}m fiducialization error must be divided between these three steps. The wire must be positioned onto the quadrupole magnetic axis to within 10 {micro}m, the wire position must be measured relative to tooling balls on the wire position detectors to within 15 {micro}m, and tooling balls on the wire position detectors must be related to tooling balls on the quadrupole to within 10 {micro}m. The techniques used in these three steps will be discussed. The note begins by discussing various quadrupole fiducialization techniques used in the past and discusses why the vibrating wire technique is our method of choice. We then give an overview of the measurement system showing how the vibrating wire is positioned onto the quadrupole axis, how the wire position detectors locate the wire relative to tooling balls without touching the wire, and how the tooling ball positions are all measured. The novel feature of this system is the vibrating wire which we discuss in depth. We analyze the wire dynamics and calculate the expected sensitivity of the system. The note should be an aid in debugging the system by providing calculations to compare measurements to.

Wolf, Zachary

2010-12-13T23:59:59.000Z

230

Argonne CNM Highlight: Damping of acoustic vibrations in gold nanoparticles  

NLE Websites -- All DOE Office Websites (Extended Search)

Damping of acoustic vibrations in gold nanoparticles Damping of acoustic vibrations in gold nanoparticles Nanopatterning of STO Vibrations in nanostructures offer applications in molecular-scale biological sensing and ultrasensitive mass detection. To approach single-atom sensing, it is necessary to reduce the dimensions of the structures to the nanometer scale while preserving long-lived vibrations. This requires an understanding of how vibrations in nanoscale objects are damped - or lose their energy to the fluid surroundings and within themselves. Researchers have used fast laser pulses to produce and probe high-frequency vibrations in metal nanoparticles. However, significant variations in particle dimensions complicate measurements. By studying bipyramid-shaped gold nanoparticles with highly uniform sizes

231

Measurement-Induced Vibrational Dynamics of a Trapped Ion  

Science Journals Connector (OSTI)

Excitation spectra of an individual trapped 138Ba+ ion show sidebands of radial and axial ion vibration in the trap. The second-order sidebands involving radial and axial vibrations would allow swapping these vibrational states; they represent an inverse Raman effect with the role of electronic and vibrational excitation interchanged. Deexcitation sidebands differ from excitation sidebands as the vibrational distribution in the D5/2 level is modified by the ion being reduced to this level in null observations of resonance light. Delayed deexcitation goes along with stochastic cooling that makes the ion collapse into the Fock state |n=1?. Sideband modulation is identified as stroboscopic detection of the light-induced nutation on a vibrational transition with ?n=±1.

B. Appasamy; Y. Stalgies; P. E. Toschek

1998-03-30T23:59:59.000Z

232

Active Vibration Control on A 3-DOF Parallel Platform Based on Kane's Dynamics Method  

E-Print Network (OSTI)

- 2783 - Active Vibration Control on A 3-DOF Parallel Platform Based on Kane's Dynamics Method Yuan be impossible without a careful isolation of the instrument from the vibration sources. To reduce the vibration low remaining vibration level. This paper is concerned with the development of a vibration isolation

Li, Yangmin

233

An experimental study of torsional vibration measurement / b  

E-Print Network (OSTI)

major problem. In some studies of torsional vibration [6] [7], vibration has been detected by a pair of matched accelerometers mounted on a disk, dia- metrically opposed to each other at equal radii. Summing the outputs of the pair increases... under consideration is the Vibration Envelope Detector Model 223A (VED), manufactured by Shaker Research Corp. To perform envelope detection, or amplitude demodu- lation, it is necessary only to build an amplitude demodulation circuit with one or two...

French, Robert Sheldon

1981-01-01T23:59:59.000Z

234

Classroom demonstration of the vibration of a bowed string  

Science Journals Connector (OSTI)

An overhead projector has been modified for stroboscopic illumination for the purpose of demonstrating the vibration of a string excited by a violinbow. The vibrational pattern is clearly delineated as are differences caused by insufficient or excessive bow force. A regime of oscillation is noted at high bow force and low speed in which alternate waves are reflected from the bow and the bridge so that the vibration transmitted to the bridge is about an octave below the fundamental frequency of the string.

E. Brock Dale

1976-01-01T23:59:59.000Z

235

Real-Time Measurement of Material Elastic Properties in a High Gamma Irradiation Environment  

SciTech Connect

This paper describes the first noncontact elastic vibration measurements of an object in a high gamma radiation field. Using a laser-coupled resonant ultrasound technique, the vibration modes of an Inconel hollow capped cylinder were measured as the gamma radiation field was increased to 104 Gy/h. This measurement technique allowed shifts in the resonant frequency of the sample’s vibration modes to be tracked over a 170-h period. The vibration mode frequencies changed in a manner consistent with the temperature dependence of the elastic stiffness coefficients of the material. These results demonstrate the efficacy of the laser approach for real-time resonant ultrasound measurements in this severely hostile nuclear environment.

Ken Telschow; Rob Schley; Dave Cottle

2006-05-01T23:59:59.000Z

236

Real-Time Measurement of Material Elastic Properties in a High Gamma Irradiation Environment  

SciTech Connect

This paper describes the first noncontact elastic vibration measurements of an object in a high gamma radiation field. Using a laser-coupled resonant ultrasound technique, the vibration modes of an Inconel hollow capped cylinder were measured as the gamma radiation field was increased to 104 Gy/h. This measurement technique allowed shifts in the resonant frequency of the sample's vibration modes to be tracked over a 170 h period. The vibration mode frequencies changed in a manner consistent with the temperature dependence of the elastic stiffness coefficients of the material. These results demonstrate the efficacy of the laser approach for real-time resonant ultrasound measurements in this severely hostile nuclear environment.

Robert S. Schley; Kenneth L. Telschow; John B. Walter; David L. Cottle

2007-08-01T23:59:59.000Z

237

Self Excited Vibration in a Specialised Electric Propulsion System  

Science Journals Connector (OSTI)

Special marine propulsion applications demand efficient manoeuvrability under extreme conditions. ... , vibration resonance and radiated noise from the propulsion shafting system must be kept to a ... purpose ves...

Don Chool Lee; Ronald D. Barro

2014-09-01T23:59:59.000Z

238

Effect of mechanical vibrations on light emitting diode luminaires.  

E-Print Network (OSTI)

??In this work, a LED and two types of Compact fluorescent lamps were investigated for the intensity variation due to mechanical vibrations in the range… (more)

Paladugu, Jayalakshmi

2009-01-01T23:59:59.000Z

239

Bending vibration measurement on rotors by laser vibrometry  

Science Journals Connector (OSTI)

A new technique is proposed for noncontact measurement of bending vibration directly from a rotating component. This notoriously difficult and previously unattained measurement is a...

Miles, Toby; Lucas, Margaret; Rothberg, Steve

1996-01-01T23:59:59.000Z

240

Photorefractive holography for 2D mechanical vibrations measurement  

Science Journals Connector (OSTI)

We report an efficient holographic setup for the real time measurement of 2D mechanical vibration modes in surfaces, based on the time-average holographic interferometry technique...

de Oliveira, Ivan; Frejlich, Jaime

Note: This page contains sample records for the topic "random vibration environment" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Transient full-field vibration measurement using spectroscopical stereo photogrammetry  

Science Journals Connector (OSTI)

Contrasted with other vibration measurement methods, a novel spectroscopical photogrammetric approach is proposed. Two colored light filters and a CCD color camera are used to...

Yue, Kaiduan; Li, Zhongke; Zhang, Ming; Chen, Shan

2010-01-01T23:59:59.000Z

242

Optical fiber sensor for membrane submicrometer vibration measurement  

Science Journals Connector (OSTI)

This paper presents an optical fiber sensor for membrane submicrometer vibration measurement. The sensor is designed ultimately for low-cost medical audiometric applications such as...

Prokopczuk, Krzysztof; Rozwadowski, Krzysztof; Aleksandra Starzy?ska, M D; Doma?ski, Andrzej W

2014-01-01T23:59:59.000Z

243

Smart Sensor Nodes for Vibration Measurement of Large Civil Infrastructure  

Science Journals Connector (OSTI)

Dynamic characteristics of large civil infrastructures have been monitored for safe operation and efficient maintenance of the structures. To measure vibration data, the conventional system uses cables which ... ...

Jong-Jae Lee; Young-Soo Park; Won-Tae Lee…

2014-01-01T23:59:59.000Z

244

Vibration measurement using phase-shifting speckle-pattern interferometry  

Science Journals Connector (OSTI)

Digital speckle-pattern interferometries for the measurement of a vibration amplitude are presented, based on phase shifting of a speckle interferogram. The calculation of the square...

Nakadate, Suezou

1986-01-01T23:59:59.000Z

245

Predicting the vibration discomfort of standing passengers in transport.  

E-Print Network (OSTI)

??It has previously been assumed that the vibration discomfort of standing people can be estimated using the same procedures developed from for seated people. In… (more)

Thuong, O.

2011-01-01T23:59:59.000Z

246

Minimax design of parallel multi-mass dynamic vibration absorbers.  

E-Print Network (OSTI)

?? This thesis discusses the design of multi-mass dynamic vibration absorbers in parallel configuration subject to uncertainties in the forcing frequency. A minimax parameter optimization… (more)

Kee, Kerk Cheng

2011-01-01T23:59:59.000Z

247

Analytical and numerical development on vibration of shells.  

E-Print Network (OSTI)

??The subject of free vibration analysis of thin cylindrical shells is one that extends well back into the last century. In general, the computational methods… (more)

Zhang, Lei

2005-01-01T23:59:59.000Z

248

Capturing inhomogeneous broadening of the -CN stretch vibration...  

NLE Websites -- All DOE Office Websites (Extended Search)

Capturing inhomogeneous broadening of the -CN stretch vibration in a Langmuir monolayer with high-resolution spectra and Capturing inhomogeneous broadening of the -CN stretch...

249

APS Protocol for Reporting Construction Vibration Issues for...  

NLE Websites -- All DOE Office Websites (Extended Search)

in the online version. Advanced Photon Source APS Protocol for Reporting Construction Vibration Issues for Beamlines Section where used: This procedure describes the process for...

250

REAL-TIME IN-SITU MEASUREMENT OF MATERIAL ELASTIC PROPERTIES IN A HIGH GAMMA IRRADIATION ENVIRONMENT  

SciTech Connect

The first measurements of elastic vibrations of an object in-situ to a high gamma irradiation field using a laser coupled resonant ultrasound method are described. A vibration mode of an Inconel hollow capped cylinder was measured throughout a period of 170 hours as the gamma radiation field was increased to 104 Gray/hour. The vibration mode frequency was observed to change in a manner consistent with the temperature dependence of the elastic stiffness coefficients of the material. These results illustrate the efficacy of the laser approach for real-time resonant ultrasound measurements in this severely hostile nuclear environment.

Ken Telschow; Rob Schley; Dave Cottle

2006-05-01T23:59:59.000Z

251

Ecology and environment  

E-Print Network (OSTI)

Ecology and environment Essentials Courses MSci (Hons) in Ecology and Environment MSci (Hons) in Ecology and Environment (research placement) BSc (Hons) in Ecology and Environment Foundation year for UK for the MSci in Ecology and Environment (research placement): AAA Typical A level offer range for the other

Sussex, University of

252

Packing Hamilton Cycles in Random and Pseudo-Random Hypergraphs  

E-Print Network (OSTI)

Packing Hamilton Cycles in Random and Pseudo-Random Hypergraphs Alan Frieze Michael Krivelevich February 16, 2011 Abstract We say that a k-uniform hypergraph C is a Hamilton cycle of type , for some 1 Hamilton cycles. A slightly weaker result is given for = k/2. We also provide sufficient conditions

Krivelevich, Michael

253

Noise control versus shock and vibration engineering  

Science Journals Connector (OSTI)

Noise control and shock and vibration engineering have many fundamentals in common and many analogous practical constraints. Yet in many respects they tend to be opposite in methodology philosophy and past history. The present discussion is an attempt to present the point of view of the practicing engineer in either field who has some perspective on the historical origins of his art. It focuses on aspects that epitomize the practical objectives of such engineers plus any administrators lawyers etc. who may also be involved in team efforts. For noise control the aspects chosen are establishment of regulations monitoring and design or other actions intended to bring about compliance with regulations. For shock and vibration engineering they are establishment of environmental specifications to ensure reliability environmental testing in accordance with these and design or redesign to bring about compliance with test requirements and also (we hope) to bring about reliability without severe penalties in weight schedule or cost. This is not to say that these aspects in their barest sense represent all the technology or methodology that is pertinent or even that these limited aspects will be treated comprehensively. It is almost self?evident that the Acoustical Society of America should and does maintain beneficial relationship with medical psychological mechanical engineering and other societies that report their particular developing lore of fundamentals and some practical information from their particular viewpoint. The Acoustical Society is an important part of this spectrum by virtue of its interdisciplinary coverage extending through materials dynamics sound instrumentation and electronics to speech and hearing. But it is also worthwhile for the ASA by whatever means are available to sample the flavor of various disciplines as unified and value?weighted in accordance with typical practical objectives. For this reason the developing beneficial relationships with the Institute of Noise Control (INCE) and the Shock and Vibration Information Center (SVIC) will become increasingly important.

Charles T. Morrow

1974-01-01T23:59:59.000Z

254

Chemical reaction versus vibrational quenching in low energy collisions of vibrationally excited OH with O  

SciTech Connect

Quantum scattering calculations are reported for state-to-state vibrational relaxation and reactive scattering in O + OH(v = 2 ? 3, j = 0) collisions on the electronically adiabatic ground state {sup 2}A?? potential energy surface of the HO{sub 2} molecule. The time-independent Schrödinger equation in hyperspherical coordinates is solved to determine energy dependent probabilities and cross sections over collision energies ranging from ultracold to 0.35 eV and for total angular momentum quantum number J = 0. A J-shifting approximation is then used to compute initial state selected reactive rate coefficients in the temperature range T = 1 ? 400 K. Results are found to be in reasonable agreement with available quasiclassical trajectory calculations. Results indicate that rate coefficients for O{sub 2} formation increase with increasing the OH vibrational level except at low and ultralow temperatures where OH(v = 0) exhibits a slightly different trend. It is found that vibrational relaxation of OH in v = 2 and v = 3 vibrational levels is dominated by a multi-quantum process.

Pradhan, G. B.; Juanes-Marcos, J. C.; Balakrishnan, N., E-mail: naduvala@unlv.nevada.edu [Department of Chemistry, University of Nevada Las Vegas, Las Vegas, Nevada 89154 (United States); Kendrick, Brian K. [Theoretical Division (T-1, MS B221), Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)] [Theoretical Division (T-1, MS B221), Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

2013-11-21T23:59:59.000Z

255

Surface Vibrations in a Model Hcp Crystal  

E-Print Network (OSTI)

-1973. R. E. Allen, G. P. Alldredge, and F. W. de Wette, Phys. Rev. B 4, 1661 (3.971). 2R. E. Allen and F. W. de Wette, Phys. Rev. 179, 873 0.969). ..., and F. W. de Wette, Phys. Rev. B4, 1661 (1971). PHYSICA L RE VIE W 8 VOLUME 6, NUMBE R 2 15 JULY 1972 Surface Vibrations in a Model hcp Crystal R. E. Allen Department of Physics, Texas A @ M University, College Station, Texas 77843 and G. P...

Allen, Roland E.; Alldredg, GP; DEWITTE, FW.

1972-01-01T23:59:59.000Z

256

Lattice Vibrations and Superconductivity in Layered Structures  

E-Print Network (OSTI)

PHYSICAL REVIEW B VOLUME 2, NUMBER 7 1 OCTOB ER, 1970 Lattice Vibrations and Superconductivity in Layered Structures* B. E. Allen, G. P. Alldredge, and F. W. de bette DePartment of Physics, University of Texas, Austin, Texas 78712 (Received 18... monolayers of identical particles, stacked atop one another to form a 21-layer slab. A side view of this system is shown in Fig. 1. The films alternately have atomic masses m and M, with m corresponding to the outermost films. The crys- tal structure...

Allen, Roland E.; Alldredg, GP; WETTE, FWD.

1970-01-01T23:59:59.000Z

257

Vibrating sample magnetometer with a step motor  

Science Journals Connector (OSTI)

A new version of the low-frequency (3.6 Hz) vibrating sample magnetometer was built. Its mechanical part consists of a crank transducer with a step motor driven by a microcontroller. Step durations are programmed in such a way that the signal from pick-up coils is perfectly sinusoidal as a function of time. The signal is narrow-band amplified, digitized at each of 400 steps of one period and lock-in detected by a computer. The magnetometer has low noise and may be used not only with superconducting but with water-cooled magnets.

V I Nizhankovskii; L B Lugansky

2007-01-01T23:59:59.000Z

258

A generalized approach to random noise synthesis: Theory and computer simulation  

Science Journals Connector (OSTI)

A generalized approach to the synthesis of Gaussian and non?Gaussian random noises as well as purely impulsive waveforms having a preselected amplitude spectrum has been developed. The basic idea behind the synthesis is to construct the amplitude?time waveform from the frequency domain i.e. from the amplitude and phase spectra. By maintaining a predetermined (reference) amplitude spectrum and performing certain specific manipulations of the phase spectrum within any selected band of frequencies and then applying the inverse discrete Fourier transform (IDFT) peaks in the non?Gaussian random waveform can be constructed from the selected band of frequencies that have been phase manipulated. Entire families of signals can thus be produced having the same energy spectrum but statistical characteristics that vary along the continuum from Gaussian (skewness=0 and kurtosis=3) through non?Gaussian (variable skewness kurtosis and crest factor) to purely impulsive (shock/transient) signals. The theoretical background and the results of a series of numerical simulations will be presented which demonstrate the functional relation between various phase spectrum manipulations and the descriptors of the synthesized random noise. The results show that the approach is viable and that the synthesized random waveforms can be easily tailored to simulate a variety of real?world acoustic/vibration signals e.g. high kurtosis (impulsive) industrial noises helicopter noises missile vibrational signals etc.

Keng D. Hsueh; Roger P. Hamernik

1990-01-01T23:59:59.000Z

259

Uncertainty quantification in vibration-based structural health monitoring for enhanced decision-making capability  

E-Print Network (OSTI)

time series measurements from vibration-based experiments.measurements, Journal of Sound and Vibration, 314(2008) 343–measurement of coherence function and input/output quantities, Journal of Sound and Vibration,

Mao, Zhu

2012-01-01T23:59:59.000Z

260

Measurement, evaluation, and assessment of peripheral neurological disorders caused by hand-transmitted vibration  

Science Journals Connector (OSTI)

Regular exposure to hand-transmitted vibration can result in symptoms and signs of ... other disorders collectively known as the hand-arm vibration syndrome. The measurement of the effects of hand-transmitted vibration

Michael J. Griffin

2008-04-01T23:59:59.000Z

Note: This page contains sample records for the topic "random vibration environment" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

Integration of Piezoelectric Sensing and Control for Nano-Scale Vibration Suppression in Hard Disk Drives  

E-Print Network (OSTI)

Time trace of vibration measurements from LDV (top) andTime trace of vibration measurements from LDV (top) and3.13: Time trace of vibration measurements from LDV (top)

Felix, Sarah Helen

2010-01-01T23:59:59.000Z

262

Vibration Spectra of Hydrocarbon Molecules. II. Skeletal Frequencies in Certain Branched Paraffins  

Science Journals Connector (OSTI)

25 October 1949 research-article Vibration Spectra of Hydrocarbon Molecules. II...characteristic frequencies should be assigned as vibrations of the carbon skeleton of these structural...problem of the interpretation of the vibration spectra of hydrocarbons is considered...

1949-01-01T23:59:59.000Z

263

Vibration of an infinite membrane supported by an array of posts  

Science Journals Connector (OSTI)

...Copyright 2000 Article Vibration of an infinite membrane supported...East Lansing, MI 48824, USA The vibration of an infinite membrane supported...an asymptotic formula. membrane, vibration| IMA Journal of Applied Mathematics......

CY Wang

2000-06-01T23:59:59.000Z

264

Better Randomness with Single Photons  

E-Print Network (OSTI)

Randomness is one of the most important resources in modern information science, since encryption founds upon the trust in random numbers. Since it is impossible to prove if an existing random bit string is truly random, it is relevant that they be generated in a trust worthy process. This requires specialized hardware for random numbers, for example a die or a tossed coin. But when all input parameters are known, their outcome might still be predicted. A quantum mechanical superposition allows for provably true random bit generation. In the past decade many quantum random number generators (QRNGs) were realized. A photonic implementation is described as a photon which impinges on a beam splitter, but such a protocol is rarely realized with non-classical light or anti-bunched single photons. Instead, laser sources or light emitting diodes are used. Here we analyze the difference in generating a true random bit string with a laser and with anti-bunched light. We show that a single photon source provides more r...

Oberreiter, Lukas

2014-01-01T23:59:59.000Z

265

Bounded Randomness Paul Brodhead1  

E-Print Network (OSTI)

kmng@ntu.edu.sg Abstract. We introduce some new variations of the notions of being Martin-L¨of random effective betting, effective regularities or effective compression. Exactly what we mean here by "effective to calibrate no- tions of randomness by varying the notion of effectivity. For example, classical Martin

Ng, Keng Meng "Selwyn"

266

Generating random thermal momenta  

E-Print Network (OSTI)

Generation of random thermal particle momenta is a basic task in many problems, such as microscopic studies of equilibrium and transport properties of systems, or the conversion of a fluid to particles. In heavy-ion physics, the (in)efficiency of the algorithm matters particularly in hybrid hydrodynamics + hadronic transport calculations. With popular software packages, such as UrQMD 3.3p1 or THERMINATOR, it can still take ten hours to generate particles for a single Pb+Pb "event" at the LHC from fluid dynamics output. Below I describe reasonably efficient simple algorithms using the MPC package, which should help speed momentum generation up by at least one order of magnitude. It is likely that this wheel has been reinvented many times instead of reuse, so there may very well exist older and/or better algorithms that I am not aware of (MPC has been around only since 2000). The main goal here is to encourage practitioners to use available efficient routines, and offer a few practical solutions.

Denes Molnar

2012-12-09T23:59:59.000Z

267

Modelling vibrations caused by tram movement on slab track line  

Science Journals Connector (OSTI)

The recent growth in the use of the railway and particularly that of the tram in urban areas highlights the need to investigate and mitigate the harmful effects associated with these means of transport. The vibrations caused by passing vehicles can be ... Keywords: Fourier Transform, Ground vibrations, Slab track, Timoshenko beam, Tram

Julia Real; Pablo MartíNez; Laura MontalbáN; Antonio Villanueva

2011-07-01T23:59:59.000Z

268

Vibration Combined High Temperature Cycle Tests for Capacitive MEMS  

E-Print Network (OSTI)

Vibration Combined High Temperature Cycle Tests for Capacitive MEMS Accelerometers Z. Szcs, G. Nagy|nagyg|hodossy|rencz|poppe>@eet.bme.hu Abstract - In this paper vibration combined high temperature cycle tests for packaged capacitive SOI- MEMS designed and realized at BME ­ DED. Twenty thermal cycles of combined Temperature Cycle Test and Fatigue

Boyer, Edmond

269

Stator Vibration Analysis of Bearingless Switched Reluctance Motors  

Science Journals Connector (OSTI)

Radial magnetic force acts on the motor stator cause large vibration and acoustic noise, that have limit the application of switched reluctance motors (SRMs). They can be aggravated when there is unbalanced force due to rotor eccentricity. This paper ... Keywords: switched reluctance motors, bearingless technique, vibration, magnetic fore, mathematic model

Yang Yan; Deng Zhiquan; Zhang Qianying; Wang Xiaolin

2010-06-01T23:59:59.000Z

270

ORIGINAL ARTICLE BUEVA: a bi-directional ultrasonic elliptical vibration  

E-Print Network (OSTI)

. Surface roughness 1 Introduction Vibration-assisted machining (VAM) and vibration-induced machining (VIM. VAM and VIM applications are quite varied [1­3]. In VAM the former, traditional tools do the cutting, it was not until the early 1990s when many different VAM and VIM designs were introduced which varied in the manner

271

Vibrational Raman Spectroscopy of High-temperature Superconductors  

E-Print Network (OSTI)

Vibrational Raman Spectroscopy of High-temperature Superconductors C. Thomsen and G. Kaczmarczyk after the discovery of high- critical-temperature Tc superconductors:2 while reports on Raman scattering Wiley & Sons Ltd, Chichester, 2002 #12;Vibrational Raman Spectroscopy of High-temperature

Nabben, Reinhard

272

Vibrational energy redistribution in glyoxal following internal conversion  

E-Print Network (OSTI)

Vibrational energy redistribution in glyoxal following internal conversion R. Naaman,a) D. M, more than 50% of the energy in S1 is transferred to the ground state by internal conversion 4 June 1979; accepted 10 August 1979) The vibrational redistribution of energy following internal

Zare, Richard N.

273

Vibration dissipation mount for motors or the like  

DOE Patents (OSTI)

A vibration dissipation mount which permits the mounting of a motor, generator, or the like such that the rotatable shaft thereof passes through the mount and the mount permits the dissipation of self-induced and otherwise induced vibrations wherein the mount comprises a pair of plates having complementary concave and convex surfaces, a semi-resilient material being disposed therebetween.

Small, Thomas R. (Brookeville, MD)

1987-01-01T23:59:59.000Z

274

Imaging photorefractive optical vibration measurement method and device  

DOE Patents (OSTI)

A method and apparatus are disclosed for characterizing a vibrating image of an object of interest. The method includes providing a sensing media having a detection resolution within a limited bandwidth and providing an object of interest having a vibrating medium. Two or more wavefronts are provided, with at least one of the wavefronts being modulated by interacting the one wavefront with the vibrating medium of the object of interest. The another wavefront is modulated such that the difference frequency between the one wavefront and the another wavefront is within a response range of the sensing media. The modulated one wavefront and another wavefront are combined in association with the sensing media to interfere and produce simultaneous vibration measurements that are distributed over the object so as to provide an image of the vibrating medium. The image has an output intensity that is substantially linear with small physical variations within the vibrating medium. Furthermore, the method includes detecting the image. In one implementation, the apparatus comprises a vibration spectrum analyzer having an emitter, a modulator, sensing media and a detector configured so as to realize such method. According to another implementation, the apparatus comprises a vibration imaging device.

Telschow, Kenneth L. (Idaho Falls, ID); Deason, Vance A. (Idaho Falls, ID); Hale, Thomas C. (Los Alamos, NM)

2000-01-01T23:59:59.000Z

275

Electromagnetic actuator to reduce vibration sources Thibaut Chailloux*  

E-Print Network (OSTI)

Electromagnetic actuator to reduce vibration sources Thibaut Chailloux* , L. Morel* , F. Sixdenier), hydraulic or pneumatic actuators, electromagnetic actuators [1], piezoelectric actuators. As part of a study to compensate a vibration on an aircraft engine for which an electromagnetic actuator was recommended. (The

Paris-Sud XI, Université de

276

The Linear Theory of Free Vibrations of a Suspended Cable  

Science Journals Connector (OSTI)

...Theory of Free Vibrations of a Suspended Cable H. M. Irvine T. K. Caughey A linear...free vibrations of a uniform suspended cable in which the ratio of sag to span is about...parameter which allows for the effects of cable geometry and elasticity. The results of...

1974-01-01T23:59:59.000Z

277

Methods for calibration of the vibration measurement system EVME used on the JAS 39 Gripen engine.  

E-Print Network (OSTI)

?? This project investigates methods for calibrating and functional testing an Engine Vibration Measurement Equipment. The equipment uses accelerometers to measure vibrations on the JAS… (more)

Backlund, Ludvig; Martin, Anna

2014-01-01T23:59:59.000Z

278

Deformation and Vibration Measurement and Data Evaluation on Large Structures Employing Optical Measurement Techniques  

Science Journals Connector (OSTI)

Deformation and vibration measurements and frequency analysis are part of complex ... development and testing time optimization for deformation and vibration measurement procedures. This paper focuses on one rece...

Hagen Berger; Markus Klein; Theodor Möller

2011-01-01T23:59:59.000Z

279

FBG-based non-contact vibration measurement and experimental study  

Science Journals Connector (OSTI)

Rotating shaft vibration measurement has important significance for condition monitoring and ... This paper presents a novel non contact radial vibration displacement measurement method based on fiber Bragg grati...

Li Wei; Zu-De Zhou; Jun Huang; Yue-Gang Tan

2013-09-01T23:59:59.000Z

280

Vibration of Axial Turbomachinery Blades: Measurement and Fluid-Structure Interactions.  

E-Print Network (OSTI)

?? The focus of this dissertation is on turbomachinery blade vibration measurements and unsteady fluid-structure interactions. Vibration of turbomachinery blades are critical to jet engine… (more)

Mikrut, Paul Louis

2012-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "random vibration environment" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

Pushing The Sample-Size Limit Of Infrared Vibrational Nano-Spectroscop...  

NLE Websites -- All DOE Office Websites (Extended Search)

The Sample-Size Limit Of Infrared Vibrational Nano-Spectroscopy: From Monolayer Towards Single molecule sensitivity. Pushing The Sample-Size Limit Of Infrared Vibrational...

282

On the Construction of Random Number Generators and Random Function Generators  

Science Journals Connector (OSTI)

Blum, Micali (1982), Yao (1982), Goldreich, Goldwasser and Micali (1984), and Luby, Rackoff (1986) have constructed random number generators, random function generators and random permutation generators

C. P. Schnorr

1988-01-01T23:59:59.000Z

283

2010 GRC VIBRATIONAL SPECTROSCOPY AUGUST 1 - AUGUST 6, 2010  

SciTech Connect

The Vibrational Spectroscopy conference focuses on using vibrational spectroscopy to probe structure and dynamics of molecules in gases, liquids, and at interfaces. The conference explores the wide range of state-of-the-art techniques based on vibrational motion. These techniques span the fields of time-domain, high-resolution frequency-domain, spatially-resolved, nonlinear and multidimensional spectroscopies. The conference highlights the application of these techniques in chemistry, materials, biology, and medicine. The theory of molecular vibrational motion and its connection to spectroscopic signatures and chemical reaction dynamics is the third major theme of the meeting. The goal is to bring together a collection of researchers who share common interests and who will gain from discussing work at the forefront of several connected areas. The intent is to emphasize the insights and understanding that studies of vibrations provide about a variety of molecular systems ranging from small polyatomic molecules to large biomolecules and nanomaterials.

Brooks Pate

2010-08-06T23:59:59.000Z

284

Proton-neutron pairing vibrations in N=Z nuclei: Precursory soft mode of isoscalar pairing condensation  

E-Print Network (OSTI)

L=0 proton-neutron ($pn$) pair-addition and pair-removal strengths in $^{40}$Ca and $^{56}$Ni are investigated by means of the $pn$ particle-particle random-phase approximation employing a Skyrme energy-density functional. It is found that the collectivity of the lowest $J^\\pi = 1^+$ state in the adjacent odd-odd nuclei becomes stronger as the strength of the isoscalar (T=0) pairing interaction increases. The results suggest the emergence of the T=0 $pn$-pairing vibrational mode as a possible critical phenomenon toward the T=0 pairing condensation.

Kenichi Yoshida

2014-09-17T23:59:59.000Z

285

Proton-neutron pairing vibrations in N=Z nuclei: Precursory soft mode of isoscalar pairing condensation  

E-Print Network (OSTI)

L=0 proton-neutron ($pn$) pair-addition and pair-removal strengths in $^{40}$Ca and $^{56}$Ni are investigated by means of the $pn$ particle-particle random-phase approximation employing a Skyrme energy-density functional. It is found that the collectivity of the lowest $J^\\pi = 1^+$ state in the adjacent odd-odd nuclei becomes stronger as the strength of the isoscalar (T=0) pairing interaction increases. The results suggest the emergence of the T=0 $pn$-pairing vibrational mode as a possible critical phenomenon toward the T=0 pairing condensation.

Yoshida, Kenichi

2014-01-01T23:59:59.000Z

286

Quantifiers for randomness of chaotic pseudo random number generators  

E-Print Network (OSTI)

We deal with randomness-quantifiers and concentrate on their ability do discern the hallmark of chaos in time-series used in connection with pseudo random number generators (PRNG). Workers in the field are motivated to use chaotic maps for generating PRNGs because of the simplicity of their implementation. Although there exist very efficient general-purpose benchmarks for testing PRNGs, we feel that the analysis provided here sheds additional didactic light on the importance of the main statistical characteristics of a chaotic map, namely, i) its invariant measure and ii) the mixing constant. This is of help in answering two questions that arise in applications, that is, (1) which is the best PRNG among the available ones? and (2) If a given PRNG turns out not to be good enough and a randomization procedure must still be applied to it, which is the best applicable randomization procedure?. Our answer provides a comparative analysis of several quantifiers advanced in the extant literature.

L. De Micco; H. A. Larrondo; A. Plastino; O. A. Rosso

2008-12-11T23:59:59.000Z

287

Reusable vibration resistant integrated circuit mounting socket  

DOE Patents (OSTI)

This invention discloses a novel form of socket for integrated circuits to be mounted on printed circuit boards. The socket uses a novel contact which is fabricated out of a bimetallic strip with a shape which makes the end of the strip move laterally as temperature changes. The end of the strip forms a barb which digs into an integrated circuit lead at normal temperatures and holds it firmly in the contact, preventing loosening and open circuits from vibration. By cooling the contact containing the bimetallic strip the barb end can be made to release so that the integrated circuit lead can be removed from the socket without damage either to the lead or to the socket components.

Evans, Craig N. (Irwin, PA)

1995-01-01T23:59:59.000Z

288

Multidimensional Random Polymers : A Renewal Approach  

E-Print Network (OSTI)

In these lecture notes, which are based on the mini-course given at 2013 Prague School on Mathematical Statistical Physics, we discuss ballistic phase of quenched and annealed stretched polymers in random environment on ${\\mathbb Z}^d$ with an emphasis on the natural renormalized renewal structures which appear in such models. In the ballistic regime an irreducible decomposition of typical polymers leads to an effectiverandom walk reinterpretation of the latter. In the annealed casethe Ornstein-Zernike theory based on this approach paves the way to an essentially complete control on the level of local limit results and invariance principles. In the quenched case, the renewal structure maps the model of stretched polymers into an effective model of directed polymers. As a result one is able to use techniques and ideas developed in the context of directed polymers in order to address issues like strong disorder in low dimensions and weak disorder in higher dimensions. Among the topics addressed: Thermodynamics of quenched and annealed models, multi-dimensional renewal theory (under Cramer's condition), renormalization and effective random walk structure of annealed polymers, very weak disorder in dimensions $d\\geq 4$ and strong disorder in dimensions $d=1,2$.

Dmitry Ioffe

2014-11-30T23:59:59.000Z

289

Ionization behavior of molecular hydrogen in intense laser fields: Influence of molecular vibration and alignment  

E-Print Network (OSTI)

The alignment- and internuclear-distance dependent ionization of H$_2$ exposed to intense, ultrashort laser fields is studied by solving the time-dependent two-electron Schr\\"odinger equation. In the regime of perturbative few-photon ionization, a strong dependence of the ionization yield on the internuclear distance is found. While this finding confirms a previously reported breakdown of the fixed-nuclei approximation for parallel alignment, a simpler explanation is provided and it is demonstrated that this breakdown is not due to vibrational dynamics during the laser pulse. The persistence of this effect even for randomly aligned molecules is demonstrated. Furthermore, the transition from the multiphoton to the quasi-static (tunneling) regime is investigated considering intense 800 nm laser pulses. While the obtained ionization yields differ significantly from the prediction of Ammosov-Delone-Krainov rates, we find a surprisingly good quantitative agreement after introducing a simple frequency-dependent cor...

Förster, Johann; Saenz, Alejandro

2014-01-01T23:59:59.000Z

290

Random time series in astronomy  

Science Journals Connector (OSTI)

...Thomas J. Maccarone Random time series in astronomy Simon Vaughan e-mail: simon.vaughan@leicester.ac.uk X-ray and Observational Astronomy Group, Department of Physics and Astronomy, University of Leicester, Leicester LE1...

2013-01-01T23:59:59.000Z

291

Randomized algorithms for reliable broadcast  

E-Print Network (OSTI)

In this thesis, we design randomized algorithms for classical problems in fault tolerant distributed computing in the full-information model. The full-information model is a strong adversarial model which imposes no ...

Vaikuntanathan, Vinod

2009-01-01T23:59:59.000Z

292

Randomization theorems for quantum channels  

E-Print Network (OSTI)

The classical randomization criterion is an important result of statistical decision theory. Recently, a quantum analogue has been proposed, giving equivalent conditions for two sets of quantum states, ensuring existence of a quantum channel mapping one set close to the other, in $L_1$-distance. In the present paper, we extend these concepts in several ways. First, sets of states are replaced by channels and randomization is performed by either post- or pre-composition with another channel. The $L_1$-distance is replaced by the diamond norm. Secondly, the maps are not required to be completely positive, but positivity is given by an admissible family of convex cones. It is shown that the randomization theorems, generalizing both quantum and classical randomization criteria, can be proved in the framework of base section norms, including the diamond norm and its dual. The theory of such norms is developed in the Appendix.

Anna Jencova

2014-04-15T23:59:59.000Z

293

Analysis of wind turbine vibrations based on SCADA data  

E-Print Network (OSTI)

Vibrations of a wind turbine have a negative impact on its performance. Mitigating this undesirable impact requires knowledge of the relationship between the vibrations and other wind turbine parameters that could be potentially modified. Three approaches for ranking the impact importance of measurable turbine parameters on the vibrations of the drive train and the tower are discussed. They include the predictor importance analysis, the global sensitivity analysis, and the correlation coefficient analysis versed in data mining and statistics. To decouple the impact of wind speed on the vibrations of the drive train and the tower, the analysis is performed on data sets with narrow speed ranges. Wavelet analysis is applied to filter noisy accelerometer data. To exclude the impact malfunctions on the vibration analysis, the data are analyzed in a frequency domain. Data-mining algorithms are used to build models with turbine parameters of interest as inputs, and the vibrations of drive train and tower as outputs. The performance of each model is thoroughly evaluated based on metrics widely used in the wind industry. The neural network algorithm outperforms other classifiers and is considered to be the most promising approach to study wind turbine vibrations. ?DOI: 10.1115/1.4001461?

Andrew Kusiak; Zijun Zhang

2010-01-01T23:59:59.000Z

294

Rotational character change of the one-phonon and two-phonon $\\gamma$ vibration in odd-$A$ nuclei  

E-Print Network (OSTI)

\\item[Background] The $\\gamma$ vibration is the most typical low-lying collective motion prevailing the nuclear chart. But only few one-phonon rotational bands in odd-$A$ nuclei have been known. Furthermore, two-phonon states, even the band head, have been observed in a very limited number of nuclides not only of odd-$A$ but even-even. \\item[Purpose] Among them, that in $^{105}$Mo is unique in that Coriolis effects are expected to be stronger than in $^{103}$Nb and $^{105}$Nb on which theoretical studies were reported. Then the purpose of the present work is to study $^{105}$Mo paying attention to rotational character change of the one-phonon and two-phonon bands in comparison with the present author's previous studies on $^{103}$Nb and $^{105}$Nb. \\item[Method] The particle-vibration coupling model based on the cranking model and the random-phase approximation is used to calculate the vibrational states in rotating odd-$A$ nuclei. \\item[Results] The present model reproduces the observed yrast zero-phonon and...

Matsuzaki, Masayuki

2014-01-01T23:59:59.000Z

295

Single-phonon and multi-phonon excitations of the $?$ vibration in rotating odd-$A$ nuclei  

E-Print Network (OSTI)

Multi-phonon excitations in atomic nuclei were observed very rarely although collective motions in quantum many-body systems are described as bosonic excitations. In particular, the first two-phonon $\\gamma$ vibrational ($2\\gamma$) excitation in odd-$A$ nuclei was reported in 2006 and only a few have been known. Quite recently, conspicuously enhanced $B(E2)$s feeding $2\\gamma$ states were observed in $^{105}$Nb and conjectured that their parent states are candidates of $3\\gamma$ states. In the present work, the model space is enlarged from the present author's previous calculation for $^{103}$Nb. The purpose is twofold: One is to see how the description of $2\\gamma$ states is improved, and the other is to examine the existence of collective $3\\gamma$ states, and when they exist, study their collectivity through calculating interband $B(E2)$s. The particle-vibration coupling model based on the cranking model and the random-phase approximation is used to calculate the vibrational states in rotating odd-$A$ nuclei. Interband $B(E2)$s are calculated by adopting the method of the generalized intensity relation. The present calculation reproduces the observed spectra of $0\\gamma$ - $2\\gamma$ states well and gives collective $3\\gamma$ states with enhanced $B(E2)$s to $2\\gamma$ states in $^{103}$Nb and $^{105}$Nb. The most collective $3\\gamma$ state with the highest $K$ at zero rotation is thought to be the main component of the observed band.

Masayuki Matsuzaki

2014-06-13T23:59:59.000Z

296

Rhodamine-doped Aerogel Random Laser  

Science Journals Connector (OSTI)

Random Laser generation can give valuable information on the structure of diffuse materials. The aerogel matrix has knowingly a fractal organization. Here, random laser generation from...

Miranda, Adriana Ramos de; Pecoraro, Édison; Ribeiro, Sidney José L; Giehl, Júlia Maria; Reijn, Saara-Maarit; Wetter, Niklaus U

297

Rotational-vibrational transitions of interstitial HD in Si  

Science Journals Connector (OSTI)

The ir spectrum of interstitial HD in Si provides unique insight into the rotational motion of interstitial H2 because the rotational-vibrational transitions for the heteronuclear HD molecule are subject to less restrictive selection rules. ir lines for transitions between rotational-vibrational states of the interstitial HD molecule with rotational quantum numbers J=0, 1, and 2 have been observed. The assignment of the rotational-vibrational spectrum of interstitial HD, with additional transitions that occur for HD but not for H2 or D2, is confirmed by uniaxial stress results.

G. Alvin Shi; Michael Stavola; W. Beall Fowler; E Elinor Chen

2005-08-03T23:59:59.000Z

298

Airflow induced vibration of the Si-IT prototype  

E-Print Network (OSTI)

In this note we present the results of air-flow induced vibration tests performed on mechanical prototypes of the Si option of the Inner Tracker upgrade. We made a modal analyze where we observed the eigenfrequency of the Si-ladder structure at ?30 Hz as previously measured at CERN. Flowing dry-air to cool the prototypes we do not observe a lock-in state of the vortex induced vibration (VIV). The maximum observed vibration amplitude is calculated. We conclude that the VIV excites the eigenfrequency almost independently from the air-flow speed, and with an amplitude which does not damage the structure.

Dijkstra, H; De Aguiar, V; Rigo, V

2014-01-01T23:59:59.000Z

299

DOE/ANL/HTRI heat exchanger tube vibration data bank  

SciTech Connect

Development of a new heat exchanger tube vibration data bank at Argonne National Laboratory is described. Comprehensive case histories on heat exchangers that have experienced tube-vibration problems and units that have been trouble-free are accumulated and this information is rendered available for evaluation, improvement, and development of vibration-prediction methods and design guidelines. Discussions include difficulties in generating a data bank, data form development, and solicitation efforts. Also included are 15 case histories upon which the data bank will be built. As new case histories are received, they will be assembled and published as addenda to this report.

Halle, H.; Chenoweth, J.M.; Wambsganss, M.W.

1980-02-01T23:59:59.000Z

300

Vibration-Induced Conductivity Fluctuation (VICOF) Testing of Soils  

E-Print Network (OSTI)

In this Letter, we propose and experimentally demonstrate a simple method to provide additional in-formation by conductivity measurements of soils. The AC electrical conductance of the soil is measured while it is exposed to a periodic vibration. The vibration-induced density fluctuation implies a corresponding conductivity fluctuation that can be seen as combination frequency components, the sum and the difference of the mean AC frequency and the double of vibration frequency, in the current response. The method is demonstrated by measurements on clayey and sandy soils.

Laszlo B. Kish; Cristine L. S. Morgan; Andrea Sz. Kishne

2005-10-31T23:59:59.000Z

Note: This page contains sample records for the topic "random vibration environment" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

Finite element modeling of nonlinear vibration behavior of piezo-integrated structures  

Science Journals Connector (OSTI)

This paper aims at finite element modeling of nonlinear vibration behavior of piezo-integrated structures subjected to weak electric field. This nonlinear vibration behavior was observed in the form of dependence of resonance frequency on the vibration ... Keywords: Finite element modeling, Modal reduction, Newmark method, Nonlinear vibration, Piezo-integrated structures

Sandeep Kumar Parashar; Utz Von Wagner; Peter Hagedorn

2013-04-01T23:59:59.000Z

302

www.elsevier.com/locate/jsvi Journal of Sound and Vibration 262 (2003) 877888  

E-Print Network (OSTI)

(2003) 877­888 Simple non-invasive measurement of rapid eye vibration M.A. Garc!ia-P!ereza, *, E. Pelib for the measurement of eye vibrations above 30 Hz is described. The method can be used in either laboratory or natural could be made if the actual vibration of the eyes (when the subject vibrates) could be measured and its

Peli, Eli

303

Active Vibration Control Based on a 3-DOF Dual Compliant Parallel Robot Using LQR Algorithm  

E-Print Network (OSTI)

Active Vibration Control Based on a 3-DOF Dual Compliant Parallel Robot Using LQR Algorithm Yuan a careful isolation of the instrument from the vibration sources by adopting active vibration isolation system to achieve a very low remaining vibration level especially for the very low frequency under 10Hz

Li, Yangmin

304

E-Print Network 3.0 - ambient vibration tests Sample Search Results  

NLE Websites -- All DOE Office Websites (Extended Search)

tests Search Powered by Explorit Topic List Advanced Search Sample search results for: ambient vibration tests...

305

Author's personal copy Journal of Sound and Vibration 311 (2008) 608622  

E-Print Network (OSTI)

Author's personal copy JOURNAL OF SOUND AND VIBRATION Journal of Sound and Vibration 311 (2008) 608 and couplings are often subjected to unbalanced axial and radial loads due to excessive machine vibrations with the associated reduction of noise, vibration, and local temperature rise. It also decreases wear of mechanical

Ray, Asok

306

Control Engineering Practice 12 (2004) 987988 Emerging technologies for active noise and vibration control systems  

E-Print Network (OSTI)

and vibration control systems Noise and vibration are often limiting factors in performance of many industrial be of little use at lower frequencies. Active noise and vibration control (ANVC) systems have emerged as viable-dimensional enclosure. One of the panels of the enclosure is vibrated, hence generating acoustic noise inside

Pota, Himanshu Roy

307

E-Print Network 3.0 - ambient vibration test Sample Search Results  

NLE Websites -- All DOE Office Websites (Extended Search)

test Search Powered by Explorit Topic List Advanced Search Sample search results for: ambient vibration test...

308

Journal of Sound and Vibration (1998) 215(5), 10651099 Article No. sv981634  

E-Print Network (OSTI)

Journal of Sound and Vibration (1998) 215(5), 1065­1099 Article No. sv981634 THE EFFECTS OF IMPERFECTIONS ON THE PERFORMANCE OF THE SUBHARMONIC VIBRATION ABSORBER SYSTEM C.-P. CHAO AND S. W. SHAW of centrifugal pendulum vibration absorbers (CPVAs) that is very effective at reducing torsional vibration levels

Shaw, Steven W.

309

Overview of VMEP (Vibration Management Enhancement Program) CBA (Cost Benefit Analysis)  

E-Print Network (OSTI)

Overview of VMEP (Vibration Management Enhancement Program) CBA (Cost Benefit Analysis) To verify Health Usage Monitoring Systems (HUMS) on SC Army NG aircraft. 2. Develop on-board vibration monitoring and approach ­Measure and record in-flight vibrations ­Process vibration data, apply signal analysis ­Methods

Giurgiutiu, Victor

310

Design and analysis of active vibration control in a microgravity environment  

E-Print Network (OSTI)

to investigate payload responses to disturbances that will most likely be present in the Space Station. Experiments were conducted first with the cart constrained to move in one dimension (one degree-of- freedom), and then with the cart having planar motion... Previous Research. Present Research III DYNAMIC MODELING. One-Dimensional Motion. Planar Motion. 6 10 IV CONTROL METHODS. 19 Position Control Velocity Control Displacement Control Combinational Control Pulse Width Modulation. 19 20 21 21 24...

Atwood, Clay Brian

2012-06-07T23:59:59.000Z

311

EPMA, EPR, electronic and vibrational spectral studies on natural aurichalcite  

Science Journals Connector (OSTI)

The electron probe micro analysis (EPMA), electron paramagnetic resonance (EPR), electronic and vibrational spectral studies on a natural mineral, aurichalcite were studied at room temperature. The EPMA...D ...

S Vedanand; B Madhu Sudhana; B J Reddy; P Sambasiva Rao

1996-12-01T23:59:59.000Z

312

Filtering Number States of the Vibrational Motion of an Ion  

E-Print Network (OSTI)

We propose a scheme to generate number states (and specific superpositions of them) of the vibrational motion of a trapped ion. In particular, we show that robust to noise qubits can be generated with arbitrary amplitudes.

Moya-Cessa, H

2000-01-01T23:59:59.000Z

313

Experiments on the Structure and Vibrations of Fractal Solids  

Science Journals Connector (OSTI)

...Structure and Vibrations of Fractal Solids E. Courtens R. Vacher Measurements performed on carefully prepared series of silica aerogels are reported. These materials were studied with small-angle neutron scattering, revealing a fractal structure that can...

1989-01-01T23:59:59.000Z

314

Neutron Storage in a Longitudinally Vibrating Silicon Crystal  

Science Journals Connector (OSTI)

The storage of cold neutrons in a longitudinally vibrating silicon crystal is demonstrated by time-resolved transmission experiments on a high-resolution backscattering spectrometer. The experimental results are compared with Monte Carlo simulations.

Hock, R.

1998-04-01T23:59:59.000Z

315

Spectroscopy and reactions of vibrationally excited transient molecules  

SciTech Connect

Spectroscopy, energy transfer and reactions of vibrationally excited transient molecules are studied through a combination of laser-based excitation techniques and efficient detection of emission from the energized molecules with frequency and time resolution. Specifically, a Time-resolved Fourier Transform Emission Spectroscopy technique has been developed for detecting dispersed laser-induced fluorescence in the IR, visible and UV regions. The structure and spectroscopy of the excited vibrational levels in the electronic ground state, as well as energy relaxation and reactions induced by specific vibronic excitations of a transient molecule can be characterized from time-resolved dispersed fluorescence in the visible and UV region. IR emissions from highly vibrational excited levels, on the other hand, reveal the pathways and rates of collision induced vibrational energy transfer.

Dai, H.L. [Univ. of Pennsylvania, Philadelphia (United States)

1993-12-01T23:59:59.000Z

316

Origin of anomalous atomic vibrations in efficient thermoelectrics...  

NLE Websites -- All DOE Office Websites (Extended Search)

Functional Materials for Energy Origin of anomalous atomic vibrations in efficient thermoelectrics revealed May 06, 2014 Figure 1: Comparison of S(Q,E) measured with INS (left) and...

317

Design and vibration testing of a flexible seal whisker model  

E-Print Network (OSTI)

Harbor seal whiskers have a unique surface structure that dramatically reduces vortex induced vibrations as they move through the water. Concurrently with rigid whisker experiments, this project focuses on the design and ...

Gerber, Christopher D

2013-01-01T23:59:59.000Z

318

A study on passive methods of vortex induced vibrations suppression  

E-Print Network (OSTI)

A number of engineering systems, including those found in offshore operations, are often affected by vortex-induced vibrations (VIV). This phenomenon is caused by the interaction between a structure and shed vortices which ...

Galvao, Richardo A

2008-01-01T23:59:59.000Z

319

A preferential vibration dissociation coupling model for nonequilibrium hypersonic flowfields  

E-Print Network (OSTI)

A preferential vibration-dissociation coupling model is incorporated into a radiatively coupled viscous shock layer code that also includes chemical, radiative, and thermal nonequilibrium. Stagnation point flow profiles are obtained for several...

McGough, David Earl

2012-06-07T23:59:59.000Z

320

Modeling of virtual standards of vibration of defective bearing units  

Science Journals Connector (OSTI)

Results of studies designed to model vibration signals are presented below. A sample of time signals obtained as a result of cranking defective and defect-free bearings of railway freight cars on a test bench ser...

V. Yu. Tetter; E. N. Sidorov; E. A. Sidorova

2013-06-01T23:59:59.000Z

Note: This page contains sample records for the topic "random vibration environment" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

Chapter 18 - Pipeline Vibration and Condition Based Maintenance  

Science Journals Connector (OSTI)

This chapter comprises two integrated parts. The first part of the chapter devotes to a detailed discussion of the mechanism leading to pipeline vibration and the effect of internal and external fluid flow on the pipeline vibration. It summarizes the formulations used for the design of optimal free span length of pipeline segments under different boundary conditions and pipeline operating conditions. Different measures used to mitigate pipeline vibration are also briefly discussed in the section. The procedures of pipeline condition based maintenance (CBM) are discussed in the second part of the chapter using vibration and other corrective maintenance (CM) parameters as asset health indicators. The typical models including P–F curve model, proportional hazard model, and proportional covariate model used to determine the optimal threshold and inspection intervals in CBM are introduced and discussed. The chapter also discusses the optimization of long-term maintenance activities using reliability based preventive maintenance decision-making approach.

Boyun Guo; Shanhong Song; Ali Ghalambor; Tian Ran Lin

2014-01-01T23:59:59.000Z

322

Measurement of small amplitudes of vibration with a laser vibrometer  

Science Journals Connector (OSTI)

A method is examined for measuring amplitudes of vibration based on harmonic analysis of the output signal of a Michelson interferometer, with modulation of the frequency of radiation in the reference arm. The...

V. G. Atavin; Yu. V. Khudyakov; E. F. Yurchik

1999-11-01T23:59:59.000Z

323

Vibration Control for Bridge Towers and Field Measurement  

Science Journals Connector (OSTI)

When the tower was under construction, there were some occasions to measure wind-induced response of the tower and also the performance of vibration control devices. Figure 9.8...shows the observed relationship, ...

Yozo Fujino; Kichiro Kimura; Hiroshi Tanaka

2012-01-01T23:59:59.000Z

324

Analog processing based vibration measurement technique using michelson interferometer  

Science Journals Connector (OSTI)

A Michelson interferometer based sensor, to monitor the displacement and vibration of a surface, is presented. The interference signals detected in quadrature are processed using analog electronics to find the...

Babar Hussain; Mushtaq Ahmed; Ghazanfar Hussain; Muhammad Saleem…

2013-06-01T23:59:59.000Z

325

Satellite vibration measurements with an autodyne CO2 laser radar  

Science Journals Connector (OSTI)

Vibration signatures of the Low Power Atmospheric Compensation Experiment satellite were obtained with a ground-based CO2 laser radar. The laser radar operated in a cw mode...

Schultz, K I; Kocher, D G; Daley, J A; Theriault, J R; Spinks, J; Fisher, S

1994-01-01T23:59:59.000Z

326

Measurement Of Flow Induced Vibration Of Reactor Component  

Science Journals Connector (OSTI)

The effect of flow-induced vibration on class I components in the reactor is a very important design factor for its qualifications worthy of loading inside the core. In this regard, a clear definition of the f...

N. Dharmaraju; K. K. Meher; A. Rama Rao

2008-01-01T23:59:59.000Z

327

Measurement of Vibration Waveforms Using Temporally Modulated Holography  

Science Journals Connector (OSTI)

The mechanical properties of the sound transmitting system, i. e. the ossicular chain and the fluid system of the inner ear, have an influence on the vibration behaviour of the tympanic membrane.

C. Sieger; R. Röhler

1979-01-01T23:59:59.000Z

328

High-speed digital holographic interferometry for vibration measurement  

SciTech Connect

A system based on digital holographic interferometry for the measurement of vibrations is presented. A high-power continuous laser(10 W) and a high-speed CCD camera are used. Hundreds of holograms of an object that has been subjected to dynamic deformation are recorded. The acquisition speed and the time of exposure of the detector are determined by the vibration frequency. Two methods are presented for triggering the camera in order to acquire at a given phase of the vibration. The phase of the wavefront is calculated from the recorded holograms by use of a two-dimensional digital Fourier-transform method. The deformation of the object is obtained from the phase. By combination of the deformations recorded at different times it is possible to reconstruct the vibration of the object.

Pedrini, Giancarlo; Osten, Wolfgang; Gusev, Mikhail E

2006-05-20T23:59:59.000Z

329

13.013J Dynamics and Vibration, Fall 2002  

E-Print Network (OSTI)

Introduction to dynamics and vibration of lumped-parameter models of mechanical systems. Three-dimensional particle kinematics. Force-momentum formulation for systems of particles and for rigid bodies (direct method). ...

Patrikalakis, N. M. (Nicholas M.)

330

Energy harvesting from wind-induced vibration of suspension bridges  

E-Print Network (OSTI)

Recently, an extensive amount of research has been focused on energy harvesting from structural vibration sources for wireless self-powered microsystem applications. One method of energy harvesting is using electromagnetic ...

Shi, Miao, M. Eng. Massachusetts Institute of Technology

2013-01-01T23:59:59.000Z

331

Nonlinear Vibration Energy Harvesting with High-Permeability Magnetic Materials  

Science Journals Connector (OSTI)

In this chapter, we introduce the recent demonstrations of high energy density nonlinear vibration energy harvesting with high-permeability magnetic materials, which show great promise for compact and wideband vi...

Xing Xing; Nian X. Sun

2013-01-01T23:59:59.000Z

332

Single-molecule reactions and spectroscopy via vibrational excitation  

Science Journals Connector (OSTI)

...J. Kelly and R. E. Palmer Single-molecule reactions and spectroscopy via...Inelastic Tunnelling|Vibration|Single Molecule|Scanning Tunnelling Microscopy (Stm)| Single-molecule reactions and spectroscopy via...

2004-01-01T23:59:59.000Z

333

Vibration Isolation of a Locomotive Mounted Energy Storage Flywheel  

E-Print Network (OSTI)

Utilizing flywheels to store and reuse energy from regenerative braking on locomotives is a new technology being developed in the Vibration Control and Electromechanics Lab at Texas A&M. This thesis focuses on the motion analysis of a locomotive...

Zhang, Xiaohua

2011-02-22T23:59:59.000Z

334

Vibration analysis by speckle techniques in real time  

Science Journals Connector (OSTI)

Vibration analysis in quasi-real time is studied by recording the time-averaged speckle pattern in a bismuth silicon oxide crystal (Bi12SiO20). When the crystal...

Tiziani, H J; Klenk, J

1981-01-01T23:59:59.000Z

335

Active vibration cancellation of tonal disturbance using orthogonal eigenstructure control  

E-Print Network (OSTI)

Orthogonal Eigenstructure Control (OEC) is a novel control method that can be used for active vibration cancellation. OEC is an output feedback control method applicable to multiple-input, multiple-output linear systems. ...

Rastgaar Aagaah, Mohammad

336

Vibration-insensitive fiber-optic current sensor  

Science Journals Connector (OSTI)

The measurement of the electric current with an optical fiber sensor can be made insensitive to external vibrations that act on the leading fiber by using a circuit involving a...

Pistoni, Natale C; Martinelli, Mario

1993-01-01T23:59:59.000Z

337

Orientational relaxation and vibrational excitation transfer in methanolcarbon tetrachloride solutions  

E-Print Network (OSTI)

Orientational relaxation and vibrational excitation transfer in methanol­carbon tetrachloride spectroscopy of the hydroxyl stretch of methanol in carbon tetrachloride solutions to study orientational excitation transfer. For concentrated methanol in carbon tetrachloride solu- tions, like those used

Fayer, Michael D.

338

Vibration Testing of Bridge Stay Cables to Obtain Damping Values  

Science Journals Connector (OSTI)

This paper discusses a series of tests performed on a cable stayed bridge in British Columbia, Canada to obtain the cable damping properties. Free vibration tests were performed on selected cables, in two phases:...

Martin E. Turek; Carlos E. Ventura; Khaled Shawwaf

2011-01-01T23:59:59.000Z

339

Suppression of the vibrations of wind turbine towers  

Science Journals Connector (OSTI)

......suppression of the vibrations of wind turbine towers. As a source of renewable and clean energy, wind power is rapidly increasing its...capacity in many countries. Large offshore turbines are subjected to severe weather......

Xiaowei Zhao; George Weiss

2011-09-01T23:59:59.000Z

340

Optical manipulation of intrinsic localized vibrational energy in cantilever arrays  

E-Print Network (OSTI)

Optically-induced real-time impurity modes are used to shepherd intrinsic localized vibrational modes (discrete breathers) along micromechanical arrays via either attractive or replulsive interactions. Adding an electrode to the cantilever array provides control of the sign of lattice anharmonicity, hence allowing both hard and soft nonlinearities to be studied. A number of dynamical effects are demonstrated and explained, including the optical tweezing of localized vibrational energy in a nonlinear lattice.

M. Sato; B. E. Hubbard; A. J. Sievers; B. Ilic; H. G. Craighead

2004-03-16T23:59:59.000Z

Note: This page contains sample records for the topic "random vibration environment" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

An experimental study of the vibration of modified cantilever plates  

E-Print Network (OSTI)

and Description of Apparatus ~ OI. Results. IV. Discussion of Results. . . . . . . V. Conclusions and Reoammendations. A kN EXFjRIMEETJLL STUDI OF THE VIBELTION GF MODIFIED CAWTILEVER PLATES In modern aircraft and missile design the trend is toward flatter... wings and larger sweep angles. For complete vibration and flutter anal- ysis of these components it is necessary that the modes and frequencies of natural vibration be closely established. Flat cantilever plates (I). serve as a good analogy...

Read, James McPherson

2012-06-07T23:59:59.000Z

342

Vibration Model Validation for Linear Collider Detector Platforms  

SciTech Connect

The ILC and CLIC reference designs incorporate reinforced-concrete platforms underneath the detectors so that the two detectors can each be moved onto and off of the beamline in a Push-Pull configuration. These platforms could potentially amplify ground vibrations, which would reduce luminosity. In this paper we compare vibration models to experimental data on reinforced concrete structures, estimate the impact on luminosity, and summarize implications for the design of a reinforced concrete platform for the ILC or CLIC detectors.

Bertsche, Kirk; Amann, J.W.; Markiewicz, T.W.; Oriunno, M.; Weidemann, A.; White, G.; /SLAC

2012-05-16T23:59:59.000Z

343

Structural vibration measurement and analysis using a novel digital sensor  

E-Print Network (OSTI)

STRUCTURAL VIBRATION MEASUREMENT AND ANALYSIS USING A NOVEL DIGITAL SENSOR A Thesis by ELIZABETH ALTAGRACIA MINIER Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree... of MASTER OF SCIENCE May 1992 Major Subject: Aerospace Engineering STRUCTURAL VIBRATION MEASUREMENT AND ANALYSIS USING A NOVEL DIGITAL SENSOR A Thesis by ELIZABETH ALTAGRACIA MINIER Approved as to style and content by: Thomas C. Pollock (Chair...

Minier, Elizabeth Altagracia

2012-06-07T23:59:59.000Z

344

An investigation of experimental methods of studying vibration of beams  

E-Print Network (OSTI)

LIBRARY A 4 M CQLLES'= OF T&X&S AN INVESTIGATION OF EXPERIMENTAL METHODS OF STUDYING VIBRATION OF BFAMS A Thesis Submitted to the Graduate School of Agricultural and Mechanical College of Texas in partial fulfillment of the requirements... for the degree Master of Science in Meohanical Engineering by Hamid Ali Shah August 1956 AN INVESTIGATION OF EXPERINENTAL NETHODS OF STUDYING VIBRATION OF BFANS A Thesis Hamid Ali Shah Style and Content Approved By& airman oi" he Committee ead of...

Shah, Hamid Ali

2012-06-07T23:59:59.000Z

345

Environment and Climate Change  

E-Print Network (OSTI)

Migration, Environment and Climate Change: ASSESSING THE EVIDENCE #12;The opinions expressed;Migration, Environment and Climate Change: ASSESSING THE EVIDENCE Edited by Frank Laczko and Christine with with the financial support of #12;3 Migration, Environment and Climate Change: Assessing the Evidence Contents

Galles, David

346

Enterococci in the Environment  

Science Journals Connector (OSTI)

...review-article Reviews Enterococci in the Environment Muruleedhara N. Byappanahalli a Meredith...understanding of their ecology in natural environments, as well as their roles as opportunistic...interactions that occur in aquatic environments. Furthermore, the use of single laboratory-grown...

Muruleedhara N. Byappanahalli; Meredith B. Nevers; Asja Korajkic; Zachery R. Staley; Valerie J. Harwood

2012-12-01T23:59:59.000Z

347

MHK Technologies/Vortex Induced Vibrations Aquatic Clean Energy VIVACE |  

Open Energy Info (EERE)

Vortex Induced Vibrations Aquatic Clean Energy VIVACE Vortex Induced Vibrations Aquatic Clean Energy VIVACE < MHK Technologies Jump to: navigation, search << Return to the MHK database homepage Vortex Induced Vibrations Aquatic Clean Energy VIVACE.jpg Technology Profile Primary Organization Vortex Hydro Energy LLC Project(s) where this technology is utilized *MHK Projects/Marine Hydrodynamics Laboratory at the University of Michigan Technology Resource Click here Current/Tidal Technology Type Click here Reciprocating Device Technology Readiness Level Click here TRL 4: Proof of Concept Technology Description The VIVACE (Vortex Induced Vibrations Aquatic Clean Energy) device is based on the extensively studied phenomenon of Vortex Induced Vibrations (VIV), which was first observed five-hundred years ago by Leonardo DaVinci in the form of 'Aeolian Tones.' VIV results from vortices forming and shedding on the downstream side of a bluff body in a current. Vortex shedding alternates from one side to the other, thereby creating a vibration or oscillation. The VIV phenomenon is non-linear, which means it can produce useful energy at high efficiency over a wide range of current speeds and directions.This converter is unlike any existing technology, as it does not use turbines, propellers, or dams. VIVACE converts the horizontal hydrokinetic energy of currents into cylinder mechanical energy. The latter is then converted to electricity through electric power generators.

348

Noise and vibration characteristics of cleanroom fan filter units  

Science Journals Connector (OSTI)

Fan filter units (FFU’s) are used increasingly by the microelectronics industry to provide recirculation air in cleanrooms. Such units usually consist of one or more direct?drive blowers located in a small discharge plenum and a HEPA or ULPA filter. There may be several hundred FFU’s in a large cleanroom. The noise and vibration generated by FFU’s differ greatly between manufacturers. Since it is difficult to apply external noise and vibration mitigation it is important to select an FFU model with appropriate noise and vibration levels so that a cleanroom served by these units will meet the prespecified noise and vibration criteria. Unfortunately FFU manufacturers usually do not provide enough information for predicting the FFU generated sound?pressure spectrum or vibration in a cleanroom. In this paper simple noise and vibration measurement methods will be described which can be used as a basis for specifying FFU performance without special testing facilities. Measured data will be presented for a number of units. Procedures will be demonstrated to predict the performance of a cleanroom which uses FFU’s as the primary source of recirculation air.

Mei Q. Wu; Colin G. Gordon

1998-01-01T23:59:59.000Z

349

Difference method for measuring the vibration sensitivity of microphones  

Science Journals Connector (OSTI)

In some applications microphones are subjected to sufficient vibration that their vibration response is of interest (e.g. feedback from earphone to microphone in wireless telephones and hearing aids). A procedure for measuring this microphone property should take into account the airborne sound produced by the apparatus. In the present method two microphones of the same type are mounted facing each other with diaphragms parallel and form the plane circular ends of a cylindrical enclosure. The dimensions of the air?filled volume between the two microphones are chosen to ensure that both microphones experience the same sound pressure. When the enclosure is vibrated in a direction normal to the plane of the microphone diaphragms (i.e. along the long axis of the cylinder) the vibration responses of the two microphones are essentially out of phase. The difference signal between the two microphone outputs will then provide a measure of the mean vibration response of the microphones from which the common airborne response of the microphones has been subtracted. The extent to which the response to sound within the apparatus interferes with the measurement of the vibration response of individual microphones may then be estimated. Results will be presented for a miniature electrical microphone.

2001-01-01T23:59:59.000Z

350

Vibration diagnosis of main journal bearings for diesel engines  

Science Journals Connector (OSTI)

A comprehensive summary of the vibration diagnosis techniques used to detect the wear of the main journal bearings in a diesel engine is presented. The load of the main journal bearing, the minimum thickness of the oil film, the oil film pressure and the locus of the crankshaft centre have been calculated based on the measured thermal parameters. Simulated wear experiments for the main journal bearing have been carried out in laboratory conditions. The strain and vibration on the main journal pedestals in the vertical direction were measured under various working conditions. The strain signals on the main journal bearing pedestal are related to the oil film forces, damped by the lubricant oil. The excitation sources and the vibration characteristics of the main journal bearing pedestal system were analysed by measuring the vibration signals. The relationships between the feature parameters of the vibration signals and the wear conditions of the main journal bearing have been obtained. It is promising, therefore, to develop and apply the vibration diagnosis technique further to detect the wear conditions of the main journal bearings online.

Yonghua Yu; Jianguo Yang

2005-01-01T23:59:59.000Z

351

Apparatus for vibrating a pipe string in a borehole  

SciTech Connect

This patent describes an apparatus for vibrating a drill string having a central axis in a borehole. The apparatus comprising means for generating at a downhole location longitudinally directional vibrations along the central axis of the drill string in response to flow of fluid through the interior of the drill string and a shock absorbing element mounted in the drill string between the apparatus and a drill bit carried by the drill string effective to substantially isolate the drill bit from the vibration induced in the drill string. Also described is a method of feeding a drill string through a mon-vertical section of borehole comprising: generating a downhole location a longitudinally directional vibration along the central axis of the drill string by oscillating a body in a axial direction relative to the drill string in response to flow of fluid through the interior of the drill string. The vibrations preventing frictional sticking of the drill string against the borehole wall; isolating a drill bit at the end of the drill string from the effects of the vibration during drilling operations; and moving the pipe longitudinally in the borehole.

Worrall, R.N.; Stulemeijer, I.P.J.M.

1990-01-02T23:59:59.000Z

352

Peri-prosthetic fracture vibration testing  

SciTech Connect

The purpose of this study is to establish a test setup and vibration analysis method to predict femoral stem seating and prevent bone fracture using accelerometer or force response data from an instrument stem and impactor. This study builds upon earlier studies to identify a means to supplement a surgeon's tactile and auditory senses by using damage identification techniques normally used for civil and mechanical structures. Testing will be conducted using foam cortical shell sawbones prepared for stems of different geometries. Each stem will be instrumented with an accelerometer. Two impactor designs will be compared: a monolithic impactor with an integrated load cell and accelerometer and a two piece impactor. Acceleration and force measurements will be taken in the direction of impaction. Signal processing techniques will be applied to the acceleration time histories to determine features that can be used to assess device seating and potential fracture. A consistent energy input will be applied using a drop tower. The effect of introducing compliance under the bone support vise will also be investigated. The ultimate goal of this study is to design an integrated portable data acquisition system capable of being used in future cadaveric testing. This paper will discuss the experimental set-up, the signal processing techniques used and the subsequent results.

Cruce, Jesse R [Los Alamos National Laboratory; Erwin, Jenny R [Los Alamos National Laboratory; Remick, Kevin R [Los Alamos National Laboratory; Cornwell, Phillip J [Los Alamos National Laboratory; Menegini, R. Michael [INDIANA UNIV.; Racanelli, Joe [STRYKER ORTHOPAEDICS

2011-01-28T23:59:59.000Z

353

Vibration of Generalized Double Well Oscillators  

E-Print Network (OSTI)

We have applied the Melnikov criterion to examine a global homoclinic bifurcation and transition to chaos in a case of a double well dynamical system with a nonlinear fractional damping term and external excitation. The usual double well Duffing potential having a negative square term and positive quartic term has been generalized to a double well potential with a negative square term and a positive one with an arbitrary real exponent $q > 2$. We have also used a fractional damping term with an arbitrary power $p$ applied to velocity which enables one to cover a wide range of realistic damping factors: from dry friction $p \\to 0$ to turbulent resistance phenomena $p=2$. Using perturbation methods we have found a critical forcing amplitude $\\mu_c$ above which the system may behave chaotically. Our results show that the vibrating system is less stable in transition to chaos for smaller $p$ satisfying an exponential scaling low. The critical amplitude $\\mu_c$ as an exponential function of $p$. The analytical results have been illustrated by numerical simulations using standard nonlinear tools such as Poincare maps and the maximal Lyapunov exponent. As usual for chosen system parameters we have identified a chaotic motion above the critical Melnikov amplitude $\\mu_c$.

Grzegorz Litak; Marek Borowiec; Arkadiusz Syta

2006-10-20T23:59:59.000Z

354

7/30/2014 Smart sensors that harvest power from sun, heat or vibrations https://ec.europa.eu/programmes/horizon2020/en/print/688 1/2  

E-Print Network (OSTI)

on Saturday, 01/03/2014 [1] European researchers have developed advanced energy harvesting technology. But what if sensors could harness energy directly from their environment ­ from the sun, from ambient heat and thermal energy as #12;7/30/2014 Smart sensors that harvest power from sun, heat or vibrations https

Rossi, Michele

355

Measurement of building foundation and ground-borne vibrations due to surface trains and subways  

Science Journals Connector (OSTI)

Abstract Buildings located near surface trains and subways are subjected to surface train and subway-induced vibrations. Cutting edge technologies in laboratories and precision manufacturing facilities often include operation of vibration sensitive equipment. Human comfort in the form of feelable vibrations and audible noise in residential and office buildings is also a concern. It is thus imperative to reduce these vibrations inside buildings to acceptable levels with the design of an efficient vibration mitigation system. Incorporation of a vibration mitigation system in a building in design phase requires prior understanding and characterization of subway and surface train-induced base excitations of buildings before and after the construction of a structure to meet serviceability criteria. The vibrations measured at the foundation slab of buildings serve as the base excitation for the building and transmit to the to upper floor levels through columns. The focus of this paper is to quantify the amplitudes and frequency contents of vibration level measured at foundation slab and compare these vibration measurements inside the building at foundation level with the open field measurements. In this context, an exploration of ground-borne vibration characteristics was performed at six sites in the Boston area. Three sites were selected for measuring train-induced vibration and another three were considered for subway-induced vibration study. Vibration measurements were performed on the building foundation slab as well as in open fields adjacent to the building. These vibration measurements were quantified and compared. It was found that in the case of surface train-induced building vibrations, open field vibration levels can be conservatively used in the design of buildings. However due to inconsistency in observations, a similar conclusion was not drawn for the case of subway-induced building vibration. This paper also provides the bases that would allow the designer to estimate the vibration levels in sensitive locations within the building. These estimated levels determine the extent to which mitigation is required to meet vibration criteria.

Masoud Sanayei; Pradeep Maurya; James A. Moore

2013-01-01T23:59:59.000Z

356

Part I -Mechanics M05M.1 -Vibration Damping With a Piston M05M.1 -Vibration Damping With a Piston  

E-Print Network (OSTI)

Part I - Mechanics M05M.1 - Vibration Damping With a Piston M05M.1 - Vibration Damping With a Piston Problem Sometimes it is required to reduce the influence of vertical floor vibration-filled pistons (which have face area A and equilibrium volume V0). The gas pressure in the cylinder is much

Petta, Jason

357

Instantaneous normal mode analysis for intermolecular and intramolecular vibrations of water from atomic point of view  

SciTech Connect

By exploiting the instantaneous normal mode (INM) analysis for models of flexible molecules, we investigate intermolecular and intramolecular vibrations of water from the atomic point of view. With two flexible SPC/E models, our investigations include three aspects about their INM spectra, which are separated into the unstable, intermolecular, bending, and stretching bands. First, the O- and H-atom contributions in the four INM bands are calculated and their stable INM spectra are compared with the power spectra of the atomic velocity autocorrelation functions. The unstable and intermolecular bands of the flexible models are also compared with those of the SPC/E model of rigid molecules. Second, we formulate the inverse participation ratio (IPR) of the INMs, respectively, for the O- and H-atom and molecule. With the IPRs, the numbers of the three species participated in the INMs are estimated so that the localization characters of the INMs in each band are studied. Further, by the ratio of the IPR of the H atom to that of the O atom, we explore the number of involved OH bond per molecule participated in the INMs. Third, by classifying simulated molecules into subensembles according to the geometry of their local environments or their H-bond configurations, we examine the local-structure effects on the bending and stretching INM bands. All of our results are verified to be insensible to the definition of H-bond. Our conclusions about the intermolecular and intramolecular vibrations in water are given.

Chen, Yu-Chun; Tang, Ping-Han [Institute of Physics, National Chiao-Tung University, Hsinchu 300, Taiwan (China)] [Institute of Physics, National Chiao-Tung University, Hsinchu 300, Taiwan (China); Wu, Ten-Ming, E-mail: tmw@faculty.nctu.edu.tw [Institute of Physics, National Chiao-Tung University, Hsinchu 300, Taiwan (China) [Institute of Physics, National Chiao-Tung University, Hsinchu 300, Taiwan (China); National Center for Theoretical Sciences, Hsinchu 300, Taiwan (China)

2013-11-28T23:59:59.000Z

358

NERSC Modules Software Environment  

NLE Websites -- All DOE Office Websites (Extended Search)

Environment » Modules Environment Environment » Modules Environment Modules Software Environment NERSC uses the module utility to manage nearly all software. There are two huge advantages of the module approach: NERSC can provide many different versions and/or installations of a single software package on a given machine, including a default version as well as several older and newer versions; and Users can easily switch to different versions or installations without having to explicitly specify different paths. With modules, the MANPATH and related environment variables are automatically managed. Users simply ``load'' and ``unload'' modules to control their environment. The module utility consists of two parts: the module command itself and the modulefiles on which it operates. Module Command

359

Random Walks and Electrical Networks Electrical Network Calculations in Random Walks in  

E-Print Network (OSTI)

Random Walks and Electrical Networks Electrical Network Calculations in Random Walks in Random 2/4/2008 1 / 23 #12;Random Walks and Electrical Networks Much of this talk is based on the book Random Walks and Electric Networks by Peter G. Doyle and J. Laurie Snell. Free download available at http

Peterson, Jonathon

360

Random partitions in statistical mechanics  

E-Print Network (OSTI)

We consider a family of distributions on spatial random partitions that provide a coupling between different models of interest: the ideal Bose gas; the zero-range process; particle clustering; and spatial permutations. These distributions are invariant for a "chain of Chinese restaurants" stochastic process. We obtain results for the distribution of the size of the largest component.

Nicholas M. Ercolani; Sabine Jansen; Daniel Ueltschi

2014-01-07T23:59:59.000Z

Note: This page contains sample records for the topic "random vibration environment" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

Applications of Random Matrix Theory  

E-Print Network (OSTI)

= ­ eigenvalues lie on the unit circle. #12;Matrices - Recall · Eigenvalues = · Symmetry important complicated! · Keep the symmetry (as imposed by physics) but let everything else be random. #12;Data · Correlation matrix of time series of stock prices · Sea-level and atmospheric pressure · Longest increasing

Wirosoetisno, Djoko

362

STAR Test Environment  

NLE Websites -- All DOE Office Websites (Extended Search)

STAR Test Environment STAR Test Environment STAR Test Environment These instructions describe how to set up the STAR environment independent of the production environment in order to test different installations in $OPTSTAR and $GROUP_DIR. If you want to modify those installations you will need access to the starofl account. Bypass STAR envionment login Edit your ~/.pdsf_setup file changing the STAR_LINUX_SETUP to "use_none" and start a new session. You should not see all the STAR environmental variables defined when you do this (and it will probably be much quicker than usual, too). Do a manual STAR login If you want to modify what test environment you use copy the test login scripts to your own working area: cp -r /common/star/startest /path/to/myworkdir/. If you don't want to modify these files you can source them directly from

363

Energy/Environment/Commissioning  

E-Print Network (OSTI)

//NESTECNESTEC Nobuo NakaharaNobuo Nakahara ICEBO/APCBCAsia Pacific Conference on Building Commissioning 2006.11.7 Opening AddressOpening AddressEnergy/Environment/CommissioningEnergy/Environment/Commissioning Call for Call... Commissioning PrincipleCommissioning Principle Evaluation PrincipleEvaluation Principle How Building & Urban Energy System How Building & Urban Energy System shall be completed and maintained?shall be completed and maintained? Mechanism of Urban Environment...

Nakahara, N.

2006-01-01T23:59:59.000Z

364

Self-mixing vibration measurement using emission frequency sinusoidal modulation  

Science Journals Connector (OSTI)

Abstract In this paper, a simplified phase demodulation scheme is applied to recover vibration trail on a laser self-mixing interferometer for noncontact vibration measurement. The emission of semiconductor laser diode is modulated by injecting sinusoidal wave, and corresponding interference signal is a quasi-sinusoid wave. The vibration mathematical model for semiconductor laser diode is theoretically educed from basic self-mixing theory, the variation of target is converted into phase information. The simulation of demodulation algorithm and standard deviation are presented and the reconstructed waveform displays a desirable consistence with various moving trails. Following the principle, a minimum experimental system is established and position variation of the target mirror driven by voltage signal is translated into phase shifts, feedback is controlled at weak level during experiment, Fourier transform is implemented to analyze phase information. The comparisons of both amplitude and velocity with a Germany Doppler vibrometer are performed to testify vibration model, the error of proposed demodulation method is less than 30 nm and achieve a high accuracy in vibration frequency. The experimental results indicate the traditional phase technology can be applied on complex optical power signal after adaption providing a feasible application prospects in industrial and scientific situation with an inexpensive semiconductor laser.

Yufeng Tao; Ming Wang; Dongmei Guo; Hui Hao; Qiang Liu

2014-01-01T23:59:59.000Z

365

Resonance tuning of piezoelectric vibration energy scavenging generators using compressive  

Science Journals Connector (OSTI)

Vibration energy scavenging, harvesting ambient vibrations in structures for conversion into usable electricity, provides a potential power source for emerging technologies including wireless sensor networks. Most vibration energy scavenging devices developed to date operate effectively at a single specific frequency dictated by the device's design. However, for this technology to be commercially viable, vibration energy scavengers that generate usable power across a range of driving frequencies must be developed. This paper details the design and testing of a tunable-resonance vibration energy scavenger which uses the novel approach of axially compressing a piezoelectric bimorph to lower its resonance frequency. It was determined that an axial preload can adjust the resonance frequency of a simply supported bimorph to 24% below its unloaded resonance frequency. The power output to a resistive load was found to be 65–90% of the nominal value at frequencies 19–24% below the unloaded resonance frequency. Prototypes were developed that produced 300–400 µW of power at driving frequencies between 200 and 250 Hz. Additionally, piezoelectric coupling coefficient values were increased using this method, with keff values rising as much as 25% from 0.37 to 0.46. Device damping increased 67% under preload, from 0.0265 to 0.0445, adversely affecting the power output at lower frequencies. A theoretical model modified to include the effects of preload on damping predicted power output to within 0–30% of values obtained experimentally. Optimal load resistance deviated significantly from theory, and merits further investigation.

Eli S Leland; Paul K Wright

2006-01-01T23:59:59.000Z

366

Indoor Environment Group  

NLE Websites -- All DOE Office Websites (Extended Search)

Indoor Environment Group Indoor Environment Group The Indoor Environment Group performs research that aims to maintain healthy and productive indoor environments while buildings are made more energy efficient. We study the links between indoor environmental quality, building ventilation, building energy efficiency and occupants' health, performance and comfort. We undertake experiments in laboratory and field settings and employ modeling to characterize indoor environmental conditions and evaluate the fate, transport and chemical transformations of indoor pollutants. We elucidate pathways of pollutant exposure, evaluate and develop energy efficient means of controlling indoor environmental quality, and provide input for related guidelines and standards. Contacts William Fisk WJFisk@lbl.gov (510) 486-5910

367

Climate Change, Drought & Environment  

Energy.gov (U.S. Department of Energy (DOE))

Afternoon Plenary Session: Current Trends in the Advanced Bioindustry Climate Change, Drought, and Environment—Michael Champ, Executive Director, The Sustainable Water Challenge

368

Modeling the indoor environment  

Science Journals Connector (OSTI)

Modeling the indoor environment ... Industrial & Engineering Chemistry Research2007 46 (23), 7489-7496 ... Environmental Science & Technology2007 41 (6), 2028-2035 ...

Barbara S. Austin; Stanley M. Greenfield; Bruce R. Weir; Gerald E. Anderson; Joseph V. Behar

1992-05-01T23:59:59.000Z

369

Virtual Control System Environment  

NLE Websites -- All DOE Office Websites (Extended Search)

Control System Environment Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin...

370

Forced Vibration Testing of a Four-Story Reinforced Concrete Building Utilizing the nees@UCLA Mobile Field Laboratory  

E-Print Network (OSTI)

a Test Ambient vibration measurement—Run1 E-W translational/baskets Ambient vibration measurement—Run2 Linear shakerempty baskets Ambient vibration measurement—Run3 month/date/

Yu, Eunjong; Skolnik, Derek; Whang, Daniel H.; Wallace, John W.

2008-01-01T23:59:59.000Z

371

Review of Probability Random Variable  

E-Print Network (OSTI)

at close 4) Height of wheel going over a rocky road #12;3 Random Variable Non-examples 1) `Heads' or `Tails' on coin 2) Red or Black ball from urn But we can make these into RV's Basic Idea ­ don't know · Temperature · Wheel height #12;5 Given Continuous RV X... What is the probability that X = x0 ? Oddity : P

Fowler, Mark

372

Thermodynamics of random copolymer melts  

Science Journals Connector (OSTI)

We report on a mean-field thermodynamic analysis of AB random copolymer melts with (backbone) composition correlations that reflect realistic polymerization conditions. Depending on the strength and sign of these correlations, multiple homogeneous phases, periodic mesophases, or disordered mesophases are possible. We identify an isotropic Lifshitz point and the critical lines that emerge from it. Our results should facilitate the design of new copolymeric materials.

Glenn H. Fredrickson and Scott T. Milner

1991-08-12T23:59:59.000Z

373

Lattice vibrations of pure and doped GaSe  

SciTech Connect

The Bridgman method is used to grow especially undoped and doped single crystals of GaSe. Composition and impurity content of the grown crystals were determined using X-ray fluorescence (XRF) method. X-ray diffraction, Raman scattering, photoluminescence (PL), and IR transmission measurements were performed at room temperature. The long wavelength lattice vibrations of four modifications of GaSe were described in the framework of modified one-layer linear-chain model which also takes into consideration the interaction of the selenium (Se) atom with the second nearest neighbor gallium (Ga) atom in the same layer. The existence of an eight-layer modification of GaSe is suggested and the vibrational frequencies of this modification are explained in the framework of a lattice dynamical model considered in the present work. Frequencies and the type of vibrations (gap, local, or resonance) for the impurity atoms were calculated and compared with the experimental results.

Allakhverdiev, K. [Materials Institute, Marmara Research Center, TUBITAK, Gebze/Kocaeli 41470 (Turkey) and Institute of Physics, Azerbaijan National Academy of Sciences, Baku AZ1143 (Azerbaijan)]. E-mail: kerim.allahverdi@mam.gov.tr; Baykara, T. [Materials Institute, Marmara Research Center, TUBITAK, Gebze/Kocaeli 41470 (Turkey); Ellialtioglu, S. [Department of Physics, Middle East Technical University, Ankara 06531 (Turkey); Hashimzade, F. [Institute of Physics, Azerbaijan National Academy of Sciences, Baku AZ1143 (Azerbaijan); Huseinova, D. [Institute of Physics, Azerbaijan National Academy of Sciences, Baku AZ1143 (Azerbaijan); Kawamura, K. [Institute of Materials Science, University of Tsukuba 305-8573 (Japan); Kaya, A.A. [Materials Institute, Marmara Research Center, TUBITAK, Gebze/Kocaeli 41470 (Turkey); Kulibekov, A.M. [Department of Physics, Mugla University, Mugla 48000 (Turkey); Onari, S. [Institute of Materials Science, University of Tsukuba 305-8573 (Japan)

2006-04-13T23:59:59.000Z

374

Semiempirical Model of Vibrational Relaxation for Estimating Absolute Rate Coefficients  

Science Journals Connector (OSTI)

The exchange of vibrational, or thermal, energy between two interacting species is one of the most fundamental properties in chemistry and physics. ... The correlation conforms reasonably well to a linear least-squares fit that is constrained to pass through the origin (dashed line) and supports the validity of the ?1/3 relationship at least for these data. ... They obtained rates for collision-induced population depletion of the initial state by two methods:? (i) the direct measurement of ki from the decay of fluorescence (this rate coefficient is labeled k4 in the notation of CR) and (ii) by a summation of the individual state-to-state rate coefficients (labeled ki = ?kif?, which was labeled ?k4(i) by CR). Figure 2a (upper plot) shows the measured rate coefficients for each vibrational level plotted as a function of vibrational energy. ...

Scott H. Kable; Alan E. W. Knight

2003-11-15T23:59:59.000Z

375

Superradiant control of ?-ray propagation by vibrating nuclear arrays  

Science Journals Connector (OSTI)

The collective nature of light interactions with atomic and nuclear ensembles yields the fascinating phenomena of superradiance and radiation trapping. We study the interaction of ? rays with a coherently vibrating periodic array of two-level nuclei. Such nuclear motion can be generated, e.g., in ionic crystals illuminated by a strong driving optical laser field. We find that deflection of the incident ? beam into the Bragg angle can be switched on and off by nuclear vibrations on a superradiant time scale determined by the collective nuclear frequency ?a, which is of the order of terahertz. Namely, if the incident ? wave is detuned from the nuclear transition by frequency ???a it passes through the static nuclear array. However, if the nuclei vibrate with frequency ? then parametric resonance can yield energy transfer into the Bragg deflected beam on the superradiant time scale, which can be used for fast control of ? rays.

Xiwen Zhang and Anatoly A. Svidzinsky

2013-09-30T23:59:59.000Z

376

High-vibration detection using motor current signature analysis  

SciTech Connect

Motor current signature analysis (CSA) has been used for several years as a diagnostic tool for electrical problems in ac, induction motors. Personnel at Oak Ridge National Laboratory have found that CSA can also provide information about system vibrations and imbalances similar to the information provided by an accelerometer. As a result, CSA techniques for monitoring the status of the equipment, such as pumps and compressors, driven by induction motors have been developed and used in dedicated monitoring systems. In this work, researchers have found that CSA responds proportionately to imbalances in rotating equipment and can be used to detect the In high-vibration conditions that can result. This report describes how vibration monitoring with CSA can be implemented and presents test data to support that use.

Castleberry, K.N.

1996-08-01T23:59:59.000Z

377

Lateral vibration effects in atomic-scale friction  

SciTech Connect

The influence of lateral vibrations on the stick-slip motion of a nanotip elastically pulled on a flat crystal surface is studied by atomic force microscopy measurements on a NaCl(001) surface in ultra-high vacuum. The slippage of the nanotip across the crystal lattice is anticipated at increasing driving amplitude, similarly to what is observed in presence of normal vibrations. This lowers the average friction force, as explained by the Prandtl-Tomlinson model with lateral vibrations superimposed at finite temperature. Nevertheless, the peak values of the lateral force, and the total energy losses, are expected to increase with the excitation amplitude, which may limit the practical relevance of this effect.

Roth, R. [Climate and Environment Physics, Physics Institute, University of Bern, Bern (Switzerland); Oeschger Centre for Climate Change Research, University of Bern, Bern (Switzerland); Fajardo, O. Y.; Mazo, J. J. [Departamento de Física de la Materia Condensada and Instituto de Ciencia de Materiales de Aragón, CSIC-Universidad de Zaragoza, 50009 Zaragoza (Spain); Meyer, E. [Department of Physics, University of Basel, Klingelbergstrasse 82, 4056 Basel (Switzerland); Gnecco, E. [Instituto Madrileño de Estudios Avanzados en Nanociencia, IMDEA Nanociencia, 28049 Madrid (Spain)

2014-02-24T23:59:59.000Z

378

Non-linear optical crystal vibration sensing device  

DOE Patents (OSTI)

A non-linear optical crystal vibration sensing device (10) including a photorefractive crystal (26) and a laser (12). The laser (12 ) produces a coherent light beam (14) which is split by a beam splitter (18) into a first laser beam (20) and a second laser beam (22). After passing through the crystal (26) the first laser beam (20) is counter-propagated back upon itself by a retro-mirror (32), creating a third laser beam (30). The laser beams (20, 22, 30) are modulated, due to the mixing effect within the crystal (26) by vibration of the crystal (30). In the third laser beam (30), modulation is stable and such modulation is converted by a photodetector (34) into a usable electrical output, intensity modulated in accordance with vibration applied to the crystal (26).

Kalibjian, Ralph (Livermore, CA)

1994-01-11T23:59:59.000Z

379

Degassing of molten alloys with the assistance of ultrasonic vibration  

DOE Patents (OSTI)

An apparatus and method are disclosed in which ultrasonic vibration is used to assist the degassing of molten metals or metal alloys thereby reducing gas content in the molten metals or alloys. High-intensity ultrasonic vibration is applied to a radiator that creates cavitation bubbles, induces acoustic streaming in the melt, and breaks up purge gas (e.g., argon or nitrogen) which is intentionally introduced in a small amount into the melt in order to collect the cavitation bubbles and to make the cavitation bubbles survive in the melt. The molten metal or alloy in one version of the invention is an aluminum alloy. The ultrasonic vibrations create cavitation bubbles and break up the large purge gas bubbles into small bubbles and disperse the bubbles in the molten metal or alloy more uniformly, resulting in a fast and clean degassing.

Han, Qingyou (Knoxville, TN); Xu, Hanbing (Knoxville, TN); Meek, Thomas T. (Knoxville, TN)

2010-03-23T23:59:59.000Z

380

Vibrational Excitation of H2 by Low-Energy Electrons  

Science Journals Connector (OSTI)

The v=0?1 vibrational cross section for H2 derived from swarm experiments is shown to be a good approximation to the sum of the cross sections for vibrational transitions that take place with and without simultaneous rotational excitation of the molecule. Experiments are described that prove that this summed cross section does not depend on whether the H2 molecules are in the J=0 or the J=1 rotational state, in agreement with a recent theoretical calculation. Reasons are given for the disagreement between the two published swarm-derived vibrational cross sections. However, the discrepancies between the threshold behavior of the cross sections determined by the swarm measurements, beam experiments, and theory have not yet been explained.

R. W. Crompton; D. K. Gibson; A. G. Robertson

1970-10-01T23:59:59.000Z

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381

Vibrational spectra of vitreous germania from first-principles  

Science Journals Connector (OSTI)

We report on a first-principles investigation of the structural and vibrational properties of vitreous germania (v-GeO2). Our work focuses on a periodic model structure of 168 atoms, but three smaller models are also studied for comparison. We first carry out a detailed structural analysis both in real and reciprocal spaces. Our study comprises the partial pair correlation functions, the angular distributions, the total neutron correlation function, the neutron and x-ray total structure factors, and the Faber-Ziman and Bhatia-Thornthon partial structure factors. We find overall good agreement with available experimental data. We then obtain the vibrational frequencies and eigenmodes. We analyze the vibrational density of states in terms of Ge and O motions, and further in terms of rocking, bending, and stretching contributions. The inelastic neutron spectrum is found to differ only marginally from the vibrational density of states. Using a methodology based on the application of finite electric fields, we derive dynamical Born charge tensors and Raman coupling tensors. For the infrared spectra, we calculate the real and imaginary parts of the dielectric function, including the high-frequency and static dielectric constants. The Raman spectra are shown to be sensitive to the medium-range structure and support an average Ge-O-Ge angle of 135°. We identify the shoulder X2 as a signature of breathing O vibrations in three-membered rings. Four-membered rings are found to contribute to the main Raman peak. We advance an interpretation for the shoulder X1 in terms of delocalized bond-bending modes. We derive bond polarizability parameters from the calculated Raman coupling tensors and demonstrate their level of reliability in reproducing the spectra. The calculated vibrational spectra all show good agreement with the respective experimental spectra.

Luigi Giacomazzi; P. Umari; Alfredo Pasquarello

2006-10-27T23:59:59.000Z

382

Population, Consumption & the Environment  

E-Print Network (OSTI)

12/11/2009 1 Population, Consumption & the Environment Alex de Sherbinin Center for International of carbon in 2001 · The ecological footprint, a composite measure of consumption measured in hectares kind of consumption is bad for the environment? 2. How are population dynamics and consumption linked

Columbia University

383

environment and agriculture  

E-Print Network (OSTI)

environment and agriculture environmentagriculture.curtin.edu.au Bachelor of Science - majorS in agriculture, environmental Biology or coaStal Zone management Science and engineering #12;t he department of environment and agriculture caters for students who are passionate about agriculture, biology, conserving

384

Precision Information Environments  

E-Print Network (OSTI)

Precision Information Environments Unforeseen events, such as the Hudson Bay incident, medium critical information and tools for support. Not all disasters or events that need support are unforeseen Information Environments (PIEs) will provide tailored access to information and decision support capabilities

385

Surface Mean-Square Amplitudes of Vibration for Nacl  

E-Print Network (OSTI)

obtained by M. Weber, E. J. Sharpe, and J. E. Miller fJ. Phys. Chem. Solids 32, 2775 (1971)]. PHYSICA L RE VIE W B VOLUME 6, NUMBE R 2 15 JULY 1972 Surface Mean-Square Amplitudes of Vibration for NaC1~ T. S. Chen, G. P. Alldredge, and F. W. de Wette..., No. 16, xi (1971). F. W. de Wette and G. E. Schacher, Phys. Rev. 137, SURFACE MEAN-SQUARE AMPLITUDES OF VIBRATION FOR NaC1 627 A78 (1965). A. A. Lucas, J. Chem. Phys. 48, 3156 (1968). Benson and co-workers have found that oversimplified models...

CHEN, TS; Alldredg, GP; Allen, Roland E.; WETTE, FWD.

1972-01-01T23:59:59.000Z

386

Vibrationally resolved photoelectron-spin-polarization spectroscopy of HI molecules  

Science Journals Connector (OSTI)

The photoemission from HI is studied separately for different vibrational levels of the ?2 final ionic states using spin-resolved photoelectron spectroscopy with circularly polarized light. Constant-ionic-state measurements of the cross sections ? and the polarization parameters A indicate that all channels are strongly influenced by autoionization resonances. By combining these data, sums of partial contributions to ? are analyzed in detail to obtain specific information on the coupling of the resonances to the outgoing partial waves ??. Apart from generally similar trends, the results show pronounced variations for different vibrational levels.

N. Böwering; M. Salzmann; M. Müller; H.-W. Klausing; U. Heinzmann

1992-01-01T23:59:59.000Z

387

System and method for damping vibration in a drill string  

DOE Patents (OSTI)

A system for damping vibration in a drill string can include a valve assembly having a supply of a fluid, a first member, and a second member capable of moving in relation to first member in response to vibration of the drill bit. The first and second members define a first and a second chamber for holding the fluid. Fluid can flow between the first and second chambers in response to the movement of the second member in relation to the first member. The valve assembly can also include a coil or a valve for varying a resistance of the fluid to flow between the first and second chambers.

Wassell, Mark Ellsworth; Turner, William Evans; Burgess, Daniel E; Perry, Carl Allison

2014-03-04T23:59:59.000Z

388

Vibration Combined High Temperature Cycle Tests for Capacitive MEMS Accelerometers  

E-Print Network (OSTI)

In this paper vibration combined high temperature cycle tests for packaged capacitive SOI-MEMS accelerometers are presented. The aim of these tests is to provide useful Design for Reliability information for MEMS designers. A high temperature test chamber and a chopper-stabilized read-out circuitry were designed and realized at BME - DED. Twenty thermal cycles of combined Temperature Cycle Test and Fatigue Vibration Test has been carried out on 5 samples. Statistical evaluation of the test results showed that degradation has started in 3 out of the 5 samples.

Z. Szucs; G. Nagy; S. Hodossy; M. Rencz; A. Poppe

2008-01-07T23:59:59.000Z

389

Time average vibration fringe analysis using Hilbert transformation  

SciTech Connect

Quantitative phase information from a single interferogram can be obtained using the Hilbert transform (HT). We have applied the HT method for quantitative evaluation of Bessel fringes obtained in time average TV holography. The method requires only one fringe pattern for the extraction of vibration amplitude and reduces the complexity in quantifying the data experienced in the time average reference bias modulation method, which uses multiple fringe frames. The technique is demonstrated for the measurement of out-of-plane vibration amplitude on a small scale specimen using a time average microscopic TV holography system.

Kumar, Upputuri Paul; Mohan, Nandigana Krishna; Kothiyal, Mahendra Prasad

2010-10-20T23:59:59.000Z

390

System and method for damping vibration in a drill string  

DOE Patents (OSTI)

A system for damping vibration in a drill string can include a valve assembly having a supply of a fluid, a first member, and a second member capable of moving in relation to first member in response to vibration of the drill bit. The first and second members define a first and a second chamber for holding the fluid. Fluid can flow between the first and second chambers in response to the movement of the second member in relation to the first member. The valve assembly can also include a coil or a valve for varying a resistance of the fluid to flow between the first and second chambers.

Wassell, Mark Ellsworth (Kingwood, TX); Turner, William Evans (Durham, CT); Burgess, Daniel E. (Middletown, CT); Perry, Carl Allison (Middletown, CT)

2008-05-27T23:59:59.000Z

391

Problems of normalizing the vibration state of gas pumping plant shafting for booster compressor stations  

Science Journals Connector (OSTI)

Work is presented and analyzed for vibration diagnostics and vibration adjustment using the example of the GPA-10DKS-04K Ural unit, developed and manufactured by NPO Iskra, on the site of DKS-3 Orenburggazprom...

S. I. Burdyugov; A. V. Cheplygin; O. V. Il’ina…

2008-01-01T23:59:59.000Z

392

Vibration damping using low-wave-speed media with applications to precision machines  

E-Print Network (OSTI)

Vibration and noise are an ever-present problem in the majority of mechanical systems, from consumer products to precision manufacturing systems. But most approaches for vibration suppression are expensive and invasive, ...

Varanasi, Kripa K. (Kripa Kiran), 1977-

2004-01-01T23:59:59.000Z

393

Use of approximation algorithms in computer-assisted laser vibration measurement  

Science Journals Connector (OSTI)

This article examines the design of a computer-assisted laser vibration meter that uses a special reflecting film stuck to the vibrating surface to eliminate the need for adjustments. Algorithms are proposed t...

V. G. Getmanov; P. A. Kuznetsov; G. G. Tertyshnyi

1997-07-01T23:59:59.000Z

394

E-Print Network 3.0 - active vibration control Sample Search...  

NLE Websites -- All DOE Office Websites (Extended Search)

procedures were programmed in the control system of the vibrator... ,22,25) the transmissibility of vibration is affected by body posture,(17-19,21,25) muscle activity,(26,27)...

395

Vibration analysis of plates by a time-averaged projection-moiré method  

Science Journals Connector (OSTI)

A time-averaged moiré principle is described that is appropriate for vibration analysis of plates. If the projected grating, deformed by the vibrating object, is superposed upon a...

Ritter, Reinhold; Meyer, Hans-Juergen

1980-01-01T23:59:59.000Z

396

Theory and Techniques for Vibration-Induced Conductivity Fluctuation testing of Soils  

E-Print Network (OSTI)

First we present and theoretically analyze the phenomenological physical picture behind Vibration-Induced Conductivity Fluctuations. We identify the relevant tensors characterizing the electromechanical response against the vibrations for both longitudinal and transversal responses. We analyze the conductivity response with acceleration type vibrations and a new scheme, measurements with more advantageous compression type vibrations that are first introduced here. Compression vibrations provide sideband spectral lines shifted by the frequency of the vibration instead of its second harmonics; moreover the application of this method is less problematic with loose electrodes. Concerning geometry and electrodes, the large measurement errors in earlier experiment indicated electrode effects which justify using four-electrode type measurements. We propose and analyze new arrangements for the longitudinal and transversal measurements with both compression vibration and acceleration vibration for laboratory and field conditions.

Hung-Chih Chang; Laszlo B. Kish; Andrea Kishne; Cristine Morgan; Chiman Kwan

2009-01-22T23:59:59.000Z

397

Modeling and Vibration Control with a Nanopositioning Magnetic-Levitation System  

E-Print Network (OSTI)

This dissertation demonstrates that a magnetic-levitation (maglev) stage has the capabilities to control movements and reject vibration simultaneously. The mathematical model and vibration control scheme with a 6-degree-of-freedom (6-DOF) maglev...

Kim, Young Ha

2012-02-14T23:59:59.000Z

398

A study of structural analysis and dynamic characteristics of a sleeve spring torsional vibration damper  

Science Journals Connector (OSTI)

In diesel engines, it is inevitable that the torsional vibration is produced by the fluctuation of engine torque. Therefore, it is necessary to ... to diminish the torsional vibration. A sleeve spring damper is o...

Beom Cheol Hwang; Chung Hwan Jeon…

2010-07-01T23:59:59.000Z

399

Random Matrix Theory, Numerical Computation and Applications  

E-Print Network (OSTI)

a precursor to a book on Random Matrix Theory that will be forthcoming. We reserve the right to reuseRandom Matrix Theory, Numerical Computation and Applications Alan Edelman, Brian D. Sutton new approaches to theory. We illustrate by describing such random matrix techniques as the stochastic

Edelman, Alan

400

Invertibility of random matrices M. Rudelson  

E-Print Network (OSTI)

Invertibility of random matrices M. Rudelson We will discuss several recent developments related to invertibility and spectral properties of large random matrices. Consider an n Ã? n matrix, whose values are independent identically distributed random variables. The invertibility questions can be roughly divided

Weinberger, Hans

Note: This page contains sample records for the topic "random vibration environment" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

Analysis of Random Number Generators Parijat Naik  

E-Print Network (OSTI)

1 Analysis of Random Number Generators Parijat Naik Department of Computer Science Oregon State generation used in practice and a comparison of their efficiency. The paper focuses on the techniques used Random number generators are used for generating an array of numbers that have a random distribution

402

Random sets lotteries and decision theory  

Science Journals Connector (OSTI)

Abstract We apply random sets theory to decision making under risk. This leads to a unifying concept which is compatible with some types of behavior like the Choquet Expected Utility and MaxMin Expected Utility. We show that the “expected utility” of a random set lottery is easy to calculate. Hence a decision making model with random sets is actually very tractable.

Marc-Arthur Diaye; Gleb Koshevoy

2014-01-01T23:59:59.000Z

403

Measurement of higher harmonics in periodic vibrations using phase-modulated TV holography with digital image processing  

Science Journals Connector (OSTI)

We separately measure the higher harmonics vibration patterns of a periodic vibrating object by using time-average TV holography and phase modulation. During measurements the frequency...

Løkberg, Ole J; Pedersen, Hans M; Valø, Hilde; Wang, Gunnar

1994-01-01T23:59:59.000Z

404

New Approach to Control of Vibrations Generated by Construction in Rock and Soil  

E-Print Network (OSTI)

to a radically new approach to vibration control: Autonomous Crack Measurement (ACM). This paper describes ACM produced by vibrations. Direct measurement of that which concerns the public ­ cracks ­ provides a controlNew Approach to Control of Vibrations Generated by Construction in Rock and Soil Nuevo Enfoque Al

405

GROUND VIBRATION AND COHERENCE LENGTH MEASUREMENTS FOR THE CLIC NANO-STABILIZATION STUDIES  

E-Print Network (OSTI)

GROUND VIBRATION AND COHERENCE LENGTH MEASUREMENTS FOR THE CLIC NANO-STABILIZATION STUDIES K requirements. For more than two decades, ground vibration measurements were made by different teams and at different CERN sites on the surface. The devices to measure nanometre sized vibrations, the analysis

Boyer, Edmond

406

ESTIMATING DAMPING PARAMETERS IN MULTI-DEGREE-OF-FREEDOM VIBRATION SYSTEMS BY BALANCING ENERGY0  

E-Print Network (OSTI)

of Vibration and Acoustics, 131 (4) 041005, 2009 Measurement of damping forces, such as dry frictionESTIMATING DAMPING PARAMETERS IN MULTI-DEGREE-OF-FREEDOM VIBRATION SYSTEMS BY BALANCING ENERGY0 B@egr.msu.edu ABSTRACT A method of estimating damping parameters for multi- degree-of-freedom vibration systems

Feeny, Brian

407

UNCERTAINTY CALIBRATION OF LARGE-ORDER MODELS OF BRIDGES USING AMBIENT VIBRATION MEASUREMENTS  

E-Print Network (OSTI)

UNCERTAINTY CALIBRATION OF LARGE-ORDER MODELS OF BRIDGES USING AMBIENT VIBRATION MEASUREMENTS frequencies and mode shapes based on ambient vibration measurements collected from a wireless mobile measuring, such as modal frequencies, modal damping ratios and mode shapes, through vibration measurements, as well

Boyer, Edmond

408

Radar Vibrometry: Investigating the Potential of RF microwaves to measure vibrations  

E-Print Network (OSTI)

Radar Vibrometry: Investigating the Potential of RF microwaves to measure vibrations K A Tsolis, C classification process. Recent research on vibrometry, the process of conducting vibration measurements. With this study we make a primary investigation of the capabilities of RF radar systems to measure vibrations. We

Haddadi, Hamed

409

Measurement of focal spread, beam divergence and vibration in HREM images CB Boothroyd1*  

E-Print Network (OSTI)

Measurement of focal spread, beam divergence and vibration in HREM images CB Boothroyd1* and RE, the measurement of focal spread, beam divergence and specimen vibration is more difficult, as these parameters from the change in the intensity around each ring measured as a function of defocus, and vibration can

Dunin-Borkowski, Rafal E.

410

HIGH AMPLITUDE VIBRATIONS DETECTION ON ROUGH SURFACES USING A PHOTOREFRACTIVE VELOCIMETER  

E-Print Network (OSTI)

of a vibrating target. It is particularly adapted to the measurement of high amplitude (as high as some mm) low to be measured with common photorefractive semiconductors and CW lasers. Keywords : vibration measurement,3]. This sensor allows to make sensitive ultrasound vibration measurements on scattering objects. Nevertheless

411

Theory of vibrational absorption sidebands in the Coulomb-blockade regime of single-molecule transistors  

E-Print Network (OSTI)

Theory of vibrational absorption sidebands in the Coulomb-blockade regime of single-molecule-driven vibrational nonequilibrium induces vibrational sidebands in single-molecule transistors which arise from.125306 PACS number s : 73.23.Hk, 73.63. b, 85.65. h I. INTRODUCTION Single-molecule junctions and transistors

von Oppen, Felix

412

Active vibration suppression of a exible structure using smart material and a modular control patch  

E-Print Network (OSTI)

Active vibration suppression of a ¯exible structure using smart material and a modular control of vibration suppression of a ¯exible structure using smart materials and a miniaturized digital controller and was developed by TRW for the United States Air Force for future space vibration control. In this research

413

Monitoring a Building Using Deconvolution Interferometry. II: Ambient-Vibration Analysis  

E-Print Network (OSTI)

Monitoring a Building Using Deconvolution Interferometry. II: Ambient- Vibration Analysis by Nori interferometry to ambient-vibration data, instead of using earthquake data, to monitor a building. The time continuity of ambient vibrations is useful for temporal monitoring. We show that, because multiple sources

Snieder, Roel

414

Noise and Vibration: Emerging Methods 5-8 April 2009 Oxford  

E-Print Network (OSTI)

NOVEM 2009 Noise and Vibration: Emerging Methods 5-8 April 2009 Oxford THE INFLUENCE OF STRONG-order terms. 1 INTRODUCTION For the design of vibrational sources and minimization of the transmitted power with physi- cal insight and absolute source data. The vibration amplitude at the source-receiver interface

Berlin,Technische Universität

415

Airbus Toulouse Flight test data centre. Diagnosis and treatment of noisy vibration flight test data.  

E-Print Network (OSTI)

Airbus Toulouse ­ Flight test data centre. Diagnosis and treatment of noisy vibration flight test data. The trainee will work within flight test vibration analysis team.The main missions and activities are the followings: - Use an automatic tool of vibration data quality defaults detection; evaluate this tool

Dobigeon, Nicolas

416

Free Vibration Analysis of Kirchoff Plates with Damaged Boundaries by the Chebyshev Collocation Method  

E-Print Network (OSTI)

Free Vibration Analysis of Kirchoff Plates with Damaged Boundaries by the Chebyshev Collocation for the free vibration analysis of slender Kirchoff plates with both mixed and damaged boundaries of the natural vibration frequencies with respect to the severity of the damaged boundary. Specifically

Butcher, Eric A.

417

Experimental Study of Active Vibration Suppression Structure Using Modular Control Patch*  

E-Print Network (OSTI)

Experimental Study of Active Vibration Suppression Structure Using Modular Control Patch* Gangbing results of vibration suppressicln of a flexible structure using a miniaturized digital controller, called for the United States Air Force for future space vibration control. In this research, the MCP is used

418

Fabrication and Optimal Strain Sensor Placement in an Instrumented Disk Drive Suspension for Vibration Suppression  

E-Print Network (OSTI)

for Vibration Suppression Kenn Oldham, Stanley Kon Computer Mechanics Laboratory (CML) University of California drive suspension with vibra- tion sensing strain gages can enhance vibration suppression in hard disk bits. As the industry targets bit densities of 1 terabit per square inch, airflow induced vibration

Horowitz, Roberto

419

Current Issues in Vibration-Based Fault Diagnostics and Prognostics Victor Giurgiutiu  

E-Print Network (OSTI)

1 Current Issues in Vibration-Based Fault Diagnostics and Prognostics Victor Giurgiutiu Mechanical Current issues in vibration-based fault diagnostics and prognostics are: (a) fault/damage identification and then classification. Keywords: structural health monitoring, active sensors, vibrations, signal analysis; smart

Giurgiutiu, Victor

420

Description of vibration transmission through isolators in terms of interface mobilities  

E-Print Network (OSTI)

Description of vibration transmission through isolators in terms of interface mobilities For the description of vibration transmission from a source to a receiver structure, the interface mobility method on the structural parameters. Project tasks The first task is a literature study for the description of vibration

Berlin,Technische Universität

Note: This page contains sample records for the topic "random vibration environment" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

Minimax design of vibration absorbers for linear damped systems Brandon Brown, Tarunraj Singh  

E-Print Network (OSTI)

Minimax design of vibration absorbers for linear damped systems Brandon Brown, Tarunraj Singh Ã? addresses the issue of design of a passive vibration absorber in the presence of uncertainties in the forcing frequency. A minimax problem is formulated to determine the parameters of a vibration absorber

Singh, Tarunraj

422

ExperimentalVerification of Vibration Absorbers Combinedwith Input Shaping for Oscillatory Systems  

E-Print Network (OSTI)

ExperimentalVerification of Vibration Absorbers Combinedwith Input Shaping for Oscillatory Systems of Technology Atlanta, GA 30332 ABSTRACT Systems that exhibit flexible dynamics are susceptible to vibration choice to deal with these vibrations, but in many cases, it is insufficient or difficult to implement

Singhose, William

423

VIBRATION AND BUCKLING OF A RECTANGULAR PLATE WITH AN INTERNAL SUPPORT  

Science Journals Connector (OSTI)

......November 1972 research-article Articles VIBRATION AND BUCKLING OF A RECTANGULAR PLATE WITH...2Northwestern University Evanston, Illinois The vibration and buckling of a rectangular plate with...square plate with an internal support. VIBRATION AND BUCKLING OF A RECTANGULAR PLATE WITH......

BERNHARD STAHL; LEON M. KEER

1972-11-01T23:59:59.000Z

424

VIBRATION OF RIGID BODIES ON NON-HOMOGENEOUS SEMI-INFINITE ELASTIC MEDIA  

Science Journals Connector (OSTI)

......November 1973 research-article Articles VIBRATION OF RIGID BODIES ON NON-HOMOGENEOUS...problems arising in the theory of the vibration of rigid bodies on non-homogeneous...dealt with the simplest torsional mode vibration. Three cases are considered here: vertical......

A. O. AWOJOBI

1973-11-01T23:59:59.000Z

425

Extraction of Vibration Components from a Rotating Propeller Model Based on Complex Empirical Mode Decomposition  

E-Print Network (OSTI)

Extraction of Vibration Components from a Rotating Propeller Model Based on Complex Empirical Mode dydynoel@kaist.ac.kr Abstract -- In this paper, we present extraction of vibration components embedded decomposition (CEMD), an extended version of EMD, is employed to extract the vibration components. With FEKO

Myung, Noh-Hoon

426

Does lattice vibration drive diffusion in zeolites? Dmitry I. Kopelevich and Hsueh-Chia Chang  

E-Print Network (OSTI)

Does lattice vibration drive diffusion in zeolites? Dmitry I. Kopelevich and Hsueh-Chia Chang 2000; accepted 1 December 2000 A method of estimation of the effect of lattice vibration as a driving unrealistic long vibrational modes and eliminate feedback due to lattice periodicity. A generalized Langevin

Chang, Hsueh-Chia

427

Randomized selection on the GPU  

SciTech Connect

We implement here a fast and memory-sparing probabilistic top N selection algorithm on the GPU. To our knowledge, this is the first direct selection in the literature for the GPU. The algorithm proceeds via a probabilistic-guess-and-chcck process searching for the Nth element. It always gives a correct result and always terminates. The use of randomization reduces the amount of data that needs heavy processing, and so reduces the average time required for the algorithm. Probabilistic Las Vegas algorithms of this kind are a form of stochastic optimization and can be well suited to more general parallel processors with limited amounts of fast memory.

Monroe, Laura Marie [Los Alamos National Laboratory; Wendelberger, Joanne R [Los Alamos National Laboratory; Michalak, Sarah E [Los Alamos National Laboratory

2011-01-13T23:59:59.000Z

428

Postprocessing for quantum random-number generators: Entropy evaluation and randomness extraction  

Science Journals Connector (OSTI)

Quantum random-number generators (QRNGs) can offer a means to generate information-theoretically provable random numbers, in principle. In practice, unfortunately, the quantum randomness is inevitably mixed with classical randomness due to classical noises. To distill this quantum randomness, one needs to quantify the randomness of the source and apply a randomness extractor. Here, we propose a generic framework for evaluating quantum randomness of real-life QRNGs by min-entropy, and apply it to two different existing quantum random-number systems in the literature. Moreover, we provide a guideline of QRNG data postprocessing for which we implement two information-theoretically provable randomness extractors: Toeplitz-hashing extractor and Trevisan's extractor.

Xiongfeng Ma; Feihu Xu; He Xu; Xiaoqing Tan; Bing Qi; Hoi-Kwong Lo

2013-06-21T23:59:59.000Z

429

Rotational character change of the one-phonon and two-phonon $?$ vibration in odd-$A$ nuclei  

E-Print Network (OSTI)

\\item[Background] The $\\gamma$ vibration is the most typical low-lying collective motion prevailing the nuclear chart. But only few one-phonon rotational bands in odd-$A$ nuclei have been known. Furthermore, two-phonon states, even the band head, have been observed in a very limited number of nuclides not only of odd-$A$ but even-even. \\item[Purpose] Among them, that in $^{105}$Mo is unique in that Coriolis effects are expected to be stronger than in $^{103}$Nb and $^{105}$Nb on which theoretical studies were reported. Then the purpose of the present work is to study $^{105}$Mo paying attention to rotational character change of the one-phonon and two-phonon bands in comparison with the present author's previous studies on $^{103}$Nb and $^{105}$Nb. \\item[Method] The particle-vibration coupling model based on the cranking model and the random-phase approximation is used to calculate the vibrational states in rotating odd-$A$ nuclei. \\item[Results] The present model reproduces the observed yrast zero-phonon and one-phonon bands well. The emerging general feature of the rotational character change from low spin to high spin is elucidated. In particular, the reason why the one-phonon band does not exhibit signature splitting is clarified. The calculated collectivity of the two-phonon states, however, is located higher than observed. \\item[Conclusions] The observed spectra of the yrast zero-phonon and one-phonon bands have been reproduced well. But properties of the two-phonon states, in particular the anharmonicity of the spectra, have not been accounted for.

Masayuki Matsuzaki

2014-10-21T23:59:59.000Z

430

ELECTRO-MAGNETO-FLUID-STRUCTURAL COUPLING PROBLEM: THE VIBRATING VISCOMETER  

E-Print Network (OSTI)

for the sensor de- sign, that couples fluid, structure and magnetism. NOMENCLATURE Q Quality factor. Angular oscillator, permanent magnets and two coils. A driven alternative current at fixed frequency is appliedELECTRO-MAGNETO-FLUID-STRUCTURAL COUPLING PROBLEM: THE VIBRATING VISCOMETER Doudou Badiane PRISME

Boyer, Edmond

431

Harvesting Energy from the Natural Vibration of Human Walking  

Science Journals Connector (OSTI)

§ School of Biochemical and Pharmaceutical Sciences, Capital Medical University, Beijing, 100069, China ... And it was also demonstrated as a direct power source for instantaneously lighting 40 commercial light-emitting diodes by harvesting the vibration energy from natural human walking. ... Forty commercial LED bulbs were lit simultaneously. ...

Weiqing Yang; Jun Chen; Guang Zhu; Jin Yang; Peng Bai; Yuanjie Su; Qingsheng Jing; Xia Cao; Zhong Lin Wang

2013-11-01T23:59:59.000Z

432

Spectroscopic probes of vibrationally excited molecules at chemically significant energies  

SciTech Connect

This project involves the application of multiple-resonance spectroscopic techniques for investigating energy transfer and dissociation dynamics of highly vibrationally excited molecules. Two major goals of this work are: (1) to provide information on potential energy surfaces of combustion related molecules at chemically significant energies, and (2) to test theoretical modes of unimolecular dissociation rates critically via quantum-state resolved measurements.

Rizzo, T.R. [Univ. of Rochester, NY (United States)

1993-12-01T23:59:59.000Z

433

Grinding media oscillation: effect on torsional vibrations in tumble mills  

E-Print Network (OSTI)

of oscillation of grinding media on torsional vibrations of the mill. A theoretical model was developed to determine the oscillating frequency of the grinding media. A 12" (0.3 m) diameter tumble mill test rig was built with a 0.5 hp DC motor. The rig is tested...

Toram, Kiran Kumar

2005-11-01T23:59:59.000Z

434

Predicting the vibrations of a spinning inflated membrane  

SciTech Connect

The primary difficulty of computing the vibration of spinning inflated membranes arises from the low natural frequencies of such systems. When such systems are rotated near their own natural frequencies the dynamics equations must account for higher order kinematics than is necessary for more rigid structures. These complications results from the membrane loads that develop within the bodies in reaction to the accelerations of the overall body. When second order kinematics act against these membrane loads, the resulting energies become of the same order as the potential and kinetic energies of the vibrations that would be calculated by first order kinematics. These complications apply to the problem addressed here. Here we consider a spin-stabilized, inflated membrane, spinning around its minor axis. This structure is very flexible and somewhat viscoelastic, so vibrations excited by the overall motion of the structure will dissipate energy of the system, thus reducing the kinetic energy. A reduction in kinetic energy consistent with a conservation of angular momentum results in coning and, eventually, tumbling. Here we must address the excitation of vibration by the rigid-body motion and then we must address the retarding effect of the energy dissipation on the rigid-body motion.

Segalman, D.J.; Slavin, A.

1993-04-01T23:59:59.000Z

435

Friction-Induced Vibrations in Railway Transportation Chandra Prakash Sharma  

E-Print Network (OSTI)

Friction-Induced Vibrations in Railway Transportation by Chandra Prakash Sharma B. Tech., Sardar;Abstract Controlling friction at the wheel-rail interface is indispensable for extending track life implementation of friction modifier system consists of a stick-tube assembly, attached through a bracket which

Phani, A. Srikantha

436

Enhanced Seebeck coefficient from carrier-induced vibrational softening  

Science Journals Connector (OSTI)

Through their electron-lattice interactions, localized carriers reduce vibrational stiffness constants in their surroundings. States with a large electronic polarizability (e.g., multiatomic localized states and states of a singlet bipolaron formed of degenerate electronic orbitals) induce exceptionally large softening. This carrier-induced softening augments the Seebeck coefficient of solids whose carriers hop between these localized states through two separate effects. One enhancement is due to a localized carrier inducing an increase in a solid’s vibrational entropy. The other contribution is proportional to the vibrational energy transferred with a carrier as it hops. Both softening contributions are independent of the carrier density. The magnitudes and temperature dependencies of these contributions to the Seebeck coefficient indicate the electronic polarizabilities of the localized states and the vibrational modes to which they are coupled. Measured softening enhancements of Seebeck coefficients are sometimes large enough (e.g., >200 ?V/K measured at 300 K in boron carbides) to significantly increase the efficiency of thermoelectric energy conversion.

David Emin

1999-03-01T23:59:59.000Z

437

Adaptive Vibration Cancellation on Large Telescopes for Stellar Interferometry  

E-Print Network (OSTI)

*a , Pierre Haguenauera , Johannes Sahlmanna,c , Gautam Vasishtb,a a European Southern Observatory, Karl-Schwarzschild to various mirrors in the optical path and must be compensated for in real time. Due to its limited bandwidth. Vibrations imparted to the primary, secondary and tertiary mirrors of the UTs are currently measured

Liske, Jochen

438

Asymmetric bubble disconnection: persistent vibration evolves into smooth contact  

E-Print Network (OSTI)

Asymmetric bubble disconnection: persistent vibration evolves into smooth contact Konstantin S bubble provides a simple example of this process. An initial asymmetry in the shape of the bubble neck that subsequently break-up into many pieces [1]. Bubble disconnection is a simpler ver- sion of the same collapse

Zhang, Wendy

439

Azimuthal Asymmetries and Vibrational Modes in Bubble Pinch-off  

E-Print Network (OSTI)

The pressure-driven inertial collapse of a cylindrical void in an inviscid liquid is an integrable, Hamiltonian system that forms a finite-time singularity as the radius of the void collapses to zero. Here it is shown that when the natural cylindrical symmetry of the void is perturbed azimuthally, the perturbation modes neither grow nor decay, but instead cause constant amplitude vibrations about the leading-order symmetric collapse. Though the amplitudes are frozen in time, they grow relative to the mean radius which is collapsing to zero, eventually overtaking the leading-order symmetric implosion. Including weak viscous dissipation destroys the integrability of the underlying symmetric implosion, and the effect on the stability spectrum is that short-wavelength disturbances are now erased as the implosion proceeds. Introducing a weak rotational flow component to the symmetric implosion dynamics causes the vibrating shapes to spin as the mean radius collapses. The above theoretical scenario is compared to a closely related experimental realization of void implosion: the disconnection of an air bubble from an underwater nozzle. There, the thin neck connecting the bubble to the nozzle implodes primarily radially inward and disconnects. Recent experiments were able to induce vibrations of the neck shape by releasing the bubble from a slot-shaped nozzle. The frequency and amplitude of the observed vibrations are consistent with the theoretical prediction once surface tension effects are taken into account.

Laura E. Schmidt

2011-12-19T23:59:59.000Z

440

IR Vibration-Rotation Spectra of the Ammonia Molecule  

Science Journals Connector (OSTI)

The IR spectrum of the ammonia inversion vibration-rotation normal mode is obtained using Fourier Transform IR Spectroscopy and analyzed using Maple, to easily obatin the relation between the N-H bond length and the H-N-H bond angle. As expected, the ...

Carl W. David

1996-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "random vibration environment" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

Vibrational modes of a rotating string Theodore J. Allen  

E-Print Network (OSTI)

find the small amplitude oscillatory motions and frequencies of oscillation of the string and mass. WeVibrational modes of a rotating string Theodore J. Allen Department of Physics, University Motivated by non-relativistic models of a QCD string, we examine the system of a non-relativistic string

Allen, Theodore J.

442

Vibrational modes of a rotating string Theodore J. Allen  

E-Print Network (OSTI)

find the small amplitude oscillatory motions and frequencies of oscillation of the string and mass. WeVibrational modes of a rotating string Theodore J. Allen Department of Physics, University Motivated by non­relativistic models of a QCD string, we examine the system of a non­relativistic string

Allen, Theodore J.

443

Environment Feature Stories  

NLE Websites -- All DOE Office Websites (Extended Search)

Environment Feature Stories Environment Feature Stories /community-environment/_assets/images/icon_earthday.jpg Environment Feature Stories Our environmental stewardship commitment: we will clean up the past, minimize impacts for current environmental operations, and create a sustainable future. Piñon trees show increased susceptibility to drought when also subjected to rising temperatures. Rising global temperatures accelerate drought-induced forest mortality Many southwestern forests in the United States will disappear or be heavily altered by 2050, according to a series of joint LANL-UNM studies. - 7/10/13 Haze of smoke emanating from the 2011 Las Conchas, NM fire. Wildfires may contribute more to global warming than previously predicted They suggest that fire emissions could contribute a lot more to the

444

BISEN: Biochemical Simulation Environment  

Science Journals Connector (OSTI)

......how to use MATLAB to generate...265 lines of MATLAB code compute...networks. In Chemical Biophysics...of Cellular Processes. (2008...Supplementary Data 1 - pdf file BISEN: Biochemical Simulation Environment...systems in the MATLAB computing......

J. Vanlier; F. Wu; F. Qi; K. C. Vinnakota; Y. Han; R. K. Dash; F. Yang; D. A. Beard

2009-03-15T23:59:59.000Z

445

Environment Chief Resigns  

Science Journals Connector (OSTI)

Environment Chief Resigns ... Copyright © 2013 Chemical & Engineering News ... Lisa P. Jackson, administrator of the Environmental Protection Agency since shortly after President Barack Obama took office in 2009, is stepping down. ...

CHERYL HOGUE

2013-01-07T23:59:59.000Z

446

INTERNATIONAL ENERGY AND ENVIRONMENT  

E-Print Network (OSTI)

in a heat pump cooling system, thereby alleviating peak electricity consumption and associated emissions substituting for banned fluorocarbon refrigerants, coping with carbon costing and reducing water consumptionINTERNATIONAL ENERGY AND ENVIRONMENT FOUNDATION Computational Fluid Dynamics Modeling

447

Measures of galaxy environment – I. What is 'environment'?  

Science Journals Connector (OSTI)

......research-article Papers Measures of galaxy environment - I. What is environment? Stuart I. Muldrew 1 * Darren J. Croton 2...Shanghai 200030, China The influence of a galaxys environment on its evolution has been studied and compared......

Stuart I. Muldrew; Darren J. Croton; Ramin A. Skibba; Frazer R. Pearce; Hong Bae Ann; Ivan K. Baldry; Sarah Brough; Yun-Young Choi; Christopher J. Conselice; Nicolas B. Cowan; Anna Gallazzi; Meghan E. Gray; Ruth Grützbauch; I-Hui Li; Changbom Park; Sergey V. Pilipenko; Bret J. Podgorzec; Aaron S. G. Robotham; David J. Wilman; Xiaohu Yang; Youcai Zhang; Stefano Zibetti

2012-01-21T23:59:59.000Z

448

Lower bounds for randomized Exclusive Write PRAMs  

SciTech Connect

In this paper we study the question: How useful is randomization in speeding up Exclusive Write PRAM computations? Our results give further evidence that randomization is of limited use in these types of computations. First we examine a compaction problem on both the CREW and EREW PRAM models, and we present randomized lower bounds which match the best deterministic lower bounds known. (For the CREW PRAM model, the lower bound is asymptotically optimal.) These are the first non-trivial randomized lower bounds known for the compaction problem on these models. We show that our lower bounds also apply to the problem of approximate compaction. Next we examine the problem of computing boolean functions on the CREW PRAM model, and we present a randomized lower bound, which improves on the previous best randomized lower bound for many boolean functions, including the OR function. (The previous lower bounds for these functions were asymptotically optimal, but we improve the constant multiplicative factor.) We also give an alternate proof for the randomized lower bound on PARITY, which was already optimal to within a constant additive factor. Lastly, we give a randomized lower bound for integer merging on an EREW PRAM which matches the best deterministic lower bound known. In all our proofs, we use the Random Adversary method, which has previously only been used for proving lower bounds on models with Concurrent Write capabilities. Thus this paper also serves to illustrate the power and generality of this method for proving parallel randomized lower bounds.

MacKenzie, P.D.

1995-05-02T23:59:59.000Z

449

Illicit drugs in the environment  

Science Journals Connector (OSTI)

...Nick Voulvoulis Illicit drugs in the environment Ettore Zuccato Sara Castiglioni...but risks for human health and the environment cannot be excluded. Morphine, cocaine...time. illicit drugs|drugs of abuse|environment|sewage treatment plant|wastewater...

2009-01-01T23:59:59.000Z

450

United Nations Environment Programme: Global Environment Outlook | Open  

Open Energy Info (EERE)

Nations Environment Programme: Global Environment Outlook Nations Environment Programme: Global Environment Outlook Jump to: navigation, search Tool Summary Name: United Nations Environment Programme: Global Environment Outlook Agency/Company /Organization: United Nations Environment Programme Topics: Co-benefits assessment, Policies/deployment programs, Resource assessment, Pathways analysis Resource Type: Dataset, Maps Website: geodata.grid.unep.ch/ United Nations Environment Programme: Global Environment Outlook Screenshot References: UNEP Data[1] Overview "The GEO Data Portal is the authoritative source for data sets used by UNEP and its partners in the Global Environment Outlook (GEO) report and other integrated environment assessments. Its online database holds more than 500 different variables, as national, subregional, regional and global

451

84 IEEE/ASME TRANSACTIONS ON MECHATRONICS, VOL. 11, NO. 1, FEBRUARY 2006 Inertial Vibration Control Using  

E-Print Network (OSTI)

84 IEEE/ASME TRANSACTIONS ON MECHATRONICS, VOL. 11, NO. 1, FEBRUARY 2006 Inertial Vibration Control to reduce the vibration experienced by a host structure. Active vibration control systems typically include, the technique of sensorless active shunt control is applied to inertial vibration absorption. An elec- trical

Fleming, Andrew J.

452

LITERATURE REVIEW Many researchers have considered various aspects of ground-borne vibration and its effects on  

E-Print Network (OSTI)

-borne vibration and its effects on buildings and their occupants, and several detailed studies have already been undertaken. Studies of the vibration sources include the work on vibration from surface vehicles by Hunt [57] and Ng [103], and that by Forrest [38] on underground railways. Studies of the vibration transmission

Talbot, James P.

453

Apparatus for measuring surface movement of an object that is subjected to external vibrations  

DOE Patents (OSTI)

A system for non-destructively measuring an object and controlling industrial processes in response to the measurement is disclosed in which an impulse laser generates a plurality of sound waves over timed increments in an object. A polarizing interferometer is used to measure surface movement of the object caused by the sound waves and sensed by phase shifts in the signal beam. A photon multiplier senses the phase shift and develops an electrical signal. A signal conditioning arrangement modifies the electrical signals to generate an average signal correlated to the sound waves which in turn is correlated to a physical or metallurgical property of the object, such as temperature, which property may then be used to control the process. External, random vibrations of the workpiece are utilized to develop discernible signals which can be sensed in the interferometer by only one photon multiplier. In addition the interferometer includes an arrangement for optimizing its sensitivity so that movement attributed to various waves can be detected in opaque objects. The interferometer also includes a mechanism for sensing objects with rough surfaces which produce speckle light patterns. Finally the interferometer per se, with the addition of a second photon multiplier is capable of accurately recording beam length distance differences with only one reading.

Kotidis, Petros A. (Waban, MA); Woodroffe, Jaime A. (North Reading, MA); Rostler, Peter S. (Newton, MA)

1997-01-01T23:59:59.000Z

454

Anomalous pairing vibration in neutron-rich Sn isotopes beyond the N=82 magic number  

E-Print Network (OSTI)

Two-neutron transfer associated with the pair correlation in superfluid neutron-rich nuclei is studied with focus on low-lying $0^+$ states in Sn isotopes beyond the N=82 magic number. We describe microscopically the two-neutron addition and removal transitions by means of the Skyrme-Hartree-Fock-Bogoliubov mean-field model and the continuum quasiparticle random phase approximation formulated in the coordinate space representation. It is found that the pair transfer strength for the transitions between the ground states becomes significantly large for the isotopes with $A \\ge 140$, reflecting very small neutron separation energy and long tails of the weakly bound $3p$ orbits. In $^{132-140}$Sn, a peculiar feature of the pair transfer is seen in transitions to low-lying excited $0^+$ states. They can be regarded as a novel kind of pair vibrational mode which is characterized by an anomalously long tail of the transition density extending to far outside of the nuclear surface, and a large strength comparable to that of the ground-state transitions. The presence of the weakly bound neutron orbits plays a central role for these anomalous behaviors.

Hirotaka Shimoyama; Masayuki Matsuo

2011-06-09T23:59:59.000Z

455

Apparatus for measuring surface movement of an object that is subjected to external vibrations  

DOE Patents (OSTI)

A system for non-destructively measuring an object and controlling industrial processes in response to the measurement is disclosed in which an impulse laser generates a plurality of sound waves over timed increments in an object. A polarizing interferometer is used to measure surface movement of the object caused by the sound waves and sensed by phase shifts in the signal beam. A photon multiplier senses the phase shift and develops an electrical signal. A signal conditioning arrangement modifies the electrical signals to generate an average signal correlated to the sound waves which in turn is correlated to a physical or metallurgical property of the object, such as temperature, which property may then be used to control the process. External, random vibrations of the workpiece are utilized to develop discernible signals which can be sensed in the interferometer by only one photon multiplier. In addition the interferometer includes an arrangement for optimizing its sensitivity so that movement attributed to various waves can be detected in opaque objects. The interferometer also includes a mechanism for sensing objects with rough surfaces which produce speckle light patterns. Finally the interferometer per se, with the addition of a second photon multiplier is capable of accurately recording beam length distance differences with only one reading. 38 figs.

Kotidis, P.A.; Woodroffe, J.A.; Rostler, P.S.

1997-04-22T23:59:59.000Z

456

GEMS in the environment  

NLE Websites -- All DOE Office Websites (Extended Search)

GEMS in the environment GEMS in the environment Name: de tar Status: N/A Age: N/A Location: N/A Country: N/A Date: Around 1993 Question: How many years will it be before Genetically Engineered Microorganisms are released into the environment? Replies: Some already have been in controlled and government-approved tests. So have some non-micro organisms, mainly some food crop plants and cattle strains. moodywj In addition to the previous response, I might add that although there are several examples of GEMS which have been released for beneficial purposes, caution must be exercised in order that a potentially harmful organism does not escape into the environment without extremely careful supervision and complete control over its spread. An example of this is the engineered bacteria which make use of crude oil as a carbon source, patented for use on oil spills. Although spraying a solution with these organisms in it can help clean up spills and decrease the OIL'S impact on the environment, you have to be careful about knowing in advance what the organisms will turn to for food once the oil is gone -- will it attack the hydrocarbons of other living organisms?

457

Geometric random inner products: A family of tests for random number generators  

Science Journals Connector (OSTI)

We present a computational scheme, GRIP (geometric random inner products), for testing the quality of random number generators. The GRIP formalism utilizes geometric probability techniques to calculate the average scalar products of random vectors distributed in geometric objects, such as circles and spheres. We show that these average scalar products define a family of geometric constants which can be used to evaluate the quality of random number generators. We explicitly apply the GRIP tests to several random number generators frequently used in Monte Carlo simulations, and demonstrate a statistical property for good random number generators.

Shu-Ju Tu and Ephraim Fischbach

2003-01-28T23:59:59.000Z

458

Evidence for energy coupling from the SiD vibration mode to the SiSi and SiO vibration modes at the SiO2 Si interface  

E-Print Network (OSTI)

. Jackson, Appl. Phys. Lett., 69, 2441 1996 , we measured the Si­H, Si­D, and other vibrational modes vibrational modes. In this letter, we present the experimental measurement of vibrational modes at the SiO2Evidence for energy coupling from the Si­D vibration mode to the Si­Si and Si­O vibration modes

Chen, Zhi

459

NERSC User Environment  

NLE Websites -- All DOE Office Websites (Extended Search)

Environment Environment NERSC User Environment Home Directories, Shells and Startup Files All NERSC systems (except PDSF) use global home directories, which are are pre-populated with startup files (also known as dot files) for all available shells. NERSC fully supports bash, csh, and tcsh as login shells. Other shells (ksh, sh, and zsh) are also available. The default shell at NERSC is csh. Changing Your Default Login Shell Use the NERSC Information management (NIM) portal if you want to to change your default login shell. To do this, select Change Shell from the NIM Actions pull-down menu. Managing Your Startup Files The "standard" dot-files are symbolic links to read-only files that NERSC controls. For each standard dot-file, there is a user-writable ".ext" file.

460

Decoherence from spin environments  

Science Journals Connector (OSTI)

We examine two exactly solvable models of decoherence—a central spin-system, (i) with and (ii) without a self-Hamiltonian, interacting with a collection of environment spins. In the absence of a self-Hamiltonian we show that in this model (introduced some time ago to illustrate environment-induced superselection) generic assumptions about the coupling strengths can lead to a universal (Gaussian) suppression of coherence between pointer states. On the other hand, we show that when the dynamics of the central spin is dominant a different regime emerges, which is characterized by a non-Gaussian decay and a dramatically different set of pointer states. We explore the regimes of validity of the Gaussian decay and discuss its relation to the spectral features of the environment and to the Loschmidt echo (or fidelity).

F. M. Cucchietti; J. P. Paz; W. H. Zurek

2005-11-29T23:59:59.000Z

Note: This page contains sample records for the topic "random vibration environment" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


461

Quantum robots and environments  

Science Journals Connector (OSTI)

Quantum robots and their interactions with environments of quantum systems are described, and their study justified. A quantum robot is a mobile quantum system that includes an on-board quantum computer and needed ancillary systems. Quantum robots carry out tasks whose goals include specified changes in the state of the environment, or carrying out measurements on the environment. Each task is a sequence of alternating computation and action phases. Computation phase activites include determination of the action to be carried out in the next phase, and recording of information on neighborhood environmental system states. Action phase activities include motion of the quantum robot and changes in the neighborhood environment system states. Models of quantum robots and their interactions with environments are described using discrete space and time. A unitary step operator T that gives the single time step dynamics is associated with each task. T=Ta+Tc is a sum of action phase and computation phase step operators. Conditions that Ta and Tc should satisfy are given along with a description of the evolution as a sum over paths of completed phase input and output states. A simple example of a task—carrying out a measurement on a very simple environment—is analyzed in detail. A decision tree for the task is presented and discussed in terms of the sums over phase paths. It is seen that no definite times or durations are associated with the phase steps in the tree, and that the tree describes the successive phase steps in each path in the sum over phase paths.

Paul Benioff

1998-08-01T23:59:59.000Z

462

The Theory of Random Laser Systems  

SciTech Connect

Studies of random laser systems are a new direction with promising potential applications and theoretical interest. The research is based on the theories of localization and laser physics. So far, the research shows that there are random lasing modes inside the systems which is quite different from the common laser systems. From the properties of the random lasing modes, they can understand the phenomena observed in the experiments, such as multi-peak and anisotropic spectrum, lasing mode number saturation, mode competition and dynamic processes, etc. To summarize, this dissertation has contributed the following in the study of random laser systems: (1) by comparing the Lamb theory with the Letokhov theory, the general formulas of the threshold length or gain of random laser systems were obtained; (2) they pointed out the vital weakness of previous time-independent methods in random laser research; (3) a new model which includes the FDTD method and the semi-classical laser theory. The solutions of this model provided an explanation of the experimental results of multi-peak and anisotropic emission spectra, predicted the saturation of lasing modes number and the length of localized lasing modes; (4) theoretical (Lamb theory) and numerical (FDTD and transfer-matrix calculation) studies of the origin of localized lasing modes in the random laser systems; and (5) proposal of using random lasing modes as a new path to study wave localization in random systems and prediction of the lasing threshold discontinuity at mobility edge.

Xunya Jiang

2002-06-27T23:59:59.000Z

463

Focusing and energy deposition inside random media  

Science Journals Connector (OSTI)

The degree of control over waves transmitted through random media is determined by characteristics of the singular values of the transmission matrix. This Letter explores focusing and...

Cheng, Xiaojun; Genack, Azriel Z

2014-01-01T23:59:59.000Z

464

How Can Random Noise Help Us  

E-Print Network (OSTI)

How Can Random Noise Help Us. Global Transports from Thermal Fluctuations. Aaron N. K. Yip. Department of Mathematics. Purdue University. 0. 1. 2. 3. 4. 5. 6.

2009-03-18T23:59:59.000Z

465

Environment scattering in GADRAS.  

SciTech Connect

Radiation transport calculations were performed to compute the angular tallies for scattered gamma-rays as a function of distance, height, and environment. Green's Functions were then used to encapsulate the results a reusable transformation function. The calculations represent the transport of photons throughout scattering surfaces that surround sources and detectors, such as the ground and walls. Utilization of these calculations in GADRAS (Gamma Detector Response and Analysis Software) enables accurate computation of environmental scattering for a variety of environments and source configurations. This capability, which agrees well with numerous experimental benchmark measurements, is now deployed with GADRAS Version 18.2 as the basis for the computation of scattered radiation.

Thoreson, Gregory G.; Mitchell, Dean James; Theisen, Lisa Anne; Harding, Lee T.

2013-09-01T23:59:59.000Z

466

Medium-solidity Vertical Axis Wind Turbines for use in Urban Environments S. Tullis, A. Fiedler, K. McLaren, S. Ziada  

E-Print Network (OSTI)

Medium-solidity Vertical Axis Wind Turbines for use in Urban Environments S. Tullis, A. Fiedler, K Vertical axis wind turbines are currently experiencing a renewed interest in small- scale applications: vertical axis wind turbines, vibration, blade aerodynamics #12;Introduction In community wind power

Tullis, Stephen

467

Flow-induced vibration of component cooling water heat exchangers  

SciTech Connect

This paper presents an evaluation of flow-induced vibration problems of component cooling water heat exchangers in one of Taipower's nuclear power stations. Specifically, it describes flow-induced vibration phenomena, tests to identify the excitation mechanisms, measurement of response characteristics, analyses to predict tube response and wear, various design alterations, and modifications of the original design. Several unique features associated with the heat exchangers are demonstrated, including energy-trapping modes, existence of tube-support-plate (TSP)-inactive modes, and fluidelastic instability of TSP-active and -inactive modes. On the basis of this evaluation, the difficulties and future research needs for the evaluation of heat exchangers are identified. 11 refs., 19 figs., 3 tabs.

Yeh, Y.S.; Chen, S.S. (Taiwan Power Co., Taipei (Taiwan). Nuclear Engineering Dept.; Argonne National Lab., IL (USA))

1990-01-01T23:59:59.000Z

468

Optical vibration sensor fabricated by femtosecond laser micromachining  

SciTech Connect

We fabricated an optical vibration sensor using a high-repetition rate femtosecond laser oscillator. The sensor consists of a single straight waveguide written across a series of three pieces of glass. The central piece is mounted on a suspended beam to make it sensitive to mechanical vibration, acceleration, or external forces. Displacement of the central piece is detected by measuring the change in optical transmission through the waveguide. The resulting sensor is small, simple, and requires no alignment. The sensor has a linear response over the frequency range 20 Hz-2 kHz, can detect accelerations as small as 0.01 m/s{sup 2}, and is nearly temperature independent.

Kamata, Masanao; Obara, Minoru; Gattass, Rafael R.; Cerami, Loren R.; Mazur, Eric [Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama, Kanagawa 223-8522 (Japan); Harvard University, 9 Oxford Street, Cambridge, Massachusetts 02138 (United States)

2005-08-01T23:59:59.000Z

469

Vibrational Stability of SRF Accelerator Test Facility at Fermilab  

SciTech Connect

Recently developed, the Superconducting Radio Frequency (SRF) Accelerator Test Facilities at Fermilab support the International Linear Collider (ILC), High Intensity Neutrino Source (HINS), a new high intensity injector (Project X) and other future machines. These facilities; Meson Detector Building (MDB) and New Muon Lab (NML) have very different foundations, structures, relative elevations with respect to grade level and surrounding soil composition. Also, there are differences in the operating equipment and their proximity to the primary machine. All the future machines have stringent operational stability requirements. The present study examines both near-field and ambient vibration in order to develop an understanding of the potential contribution of near-field sources (e.g. compressors, ultra-high and standard vacuum equipment, klystrons, modulators, utility fans and pumps) and distant noise sources to the overall system displacements. Facility vibration measurement results and methods of possible isolation from noise sources are presented and discussed.

McGee, M.W.; Volk, J.T.; /Fermilab

2009-05-01T23:59:59.000Z

470

Time-average TV holography for vibration fringe analysis  

SciTech Connect

Time-average TV holography is widely used method for vibration measurement. The method generates speckle correlation time-averaged J0 fringes that can be used for full-field qualitative visualization of mode shapes at resonant frequencies of an object under harmonic excitation. In order to map the amplitudes of vibration, quantitative evaluation of the time-averaged fringe pattern is desired. A quantitative evaluation procedure based on the phase-shifting technique used in two beam interferometry has also been adopted for this application with some modification. The existing procedure requires a large number of frames to be recorded for implementation. We propose a procedure that will reduce the number of frames required for the analysis. The TV holographic system used and the experimental results obtained with it on an edge-clamped, sinusoidally excited square aluminium plate sample are discussed.

Kumar, Upputuri Paul; Kalyani, Yanam; Mohan, Nandigana Krishna; Kothiyal, Mahendra Prasad

2009-06-01T23:59:59.000Z

471

Measurement of Lattice Vibrations in Vanadium by Neutron Scattering  

Science Journals Connector (OSTI)

The energy spectrum of slow neutrons inelastically scattered by vanadium metal has been measured by the time-of-flight technique. The neutrons gain energy by absorbing quanta of lattice vibration energy (phonons). As the nuclear scattering amplitude of vanadium is incoherent, the energy distribution of scattered neutrons is directly related to the frequency distribution of lattice vibrations. The measured neutron energy spectrum, as well as the derived frequency distribution, shows a clearly resolved double peak. This structure, which is distinctly different from the simple Debye distribution, but expected on the basis of detailed calculations, has heretofore not been amenable to direct measurement. The measured frequency distribution is compared with calculations for a body-centered cubic lattice by the Born-von Kármán theory and qualitative agreement is obtained. A more exact comparison awaits measurement of the elastic constants of vanadium.

C. M. Eisenhauer; I. Pelah; D. J. Hughes; H. Palevsky

1958-02-15T23:59:59.000Z

472

Large scale test simulations using the Virtual Environment for Test Optimization (VETO)  

SciTech Connect

The Virtual Environment for Test Optimization (VETO) is a set of simulation tools under development at Sandia to enable test engineers to do computer simulations of tests. The tool set utilizes analysis codes and test information to optimize design parameters and to provide an accurate model of the test environment which aides in the maximization of test performance, training, and safety. Previous VETO effort has included the development of two structural dynamics simulation modules that provide design and optimization tools for modal and vibration testing. These modules have allowed test engineers to model and simulate complex laboratory testing, to evaluate dynamic response behavior, and to investigate system testability. Further development of the VETO tool set will address the accurate modeling of large scale field test environments at Sandia. These field test environments provide weapon system certification capabilities and have different simulation requirements than those of laboratory testing.

Klenke, S.E.; Heffelfinger, S.R.; Bell, H.J.; Shierling, C.L.

1997-10-01T23:59:59.000Z

473

Vibrating H3+ in a Uniform Magnetic Field  

Science Journals Connector (OSTI)

Knowledge of how the rotation–vibrational states are affected by the interaction of the molecule with such a field would likely facilitate the detection of H3+ in the universe at locations with magnetic fields such as interstellar media. ... The contour lines clearly show the ridge at D3h configurations, R1 = R2. ... For arbitrary orientation of the field with respect to the line connecting the centers, the pertinent Schroedinger equation is solved by evaluating anal. ...

Héctor Medel Cobaxin; Alexander Alijah

2013-03-05T23:59:59.000Z

474

An Automated Home Made Low Cost Vibrating Sample Magnetometer  

Science Journals Connector (OSTI)

The design and operation of a homemade low cost vibrating sample magnetometer is described here. The sensitivity of this instrument is better than 10 ?2 ? emu and found to be very efficient for the measurement of magnetization of most of the ferromagnetic and other magnetic materials as a function of temperature down to 77 K and magnetic field upto 800 Oe. Both M(H) and M(T) data acquisition are fully automated employing computer and Labview software.

S. Kundu; T. K. Nath

2011-01-01T23:59:59.000Z

475

An Automated Home Made Low Cost Vibrating Sample Magnetometer  

E-Print Network (OSTI)

The design and operation of a homemade low cost vibrating sample magnetometer is described here. The sensitivity of this instrument is better than 10-2 emu and found to be very efficient for the measurement of magnetization of most of the ferromagnetic and other magnetic materials as a function of temperature down to 77 K and magnetic field upto 800 Oe. Both M(H) and M(T) data acquisition are fully automated employing computer and Labview software

Kundu, S

2011-01-01T23:59:59.000Z

476

Vibrational Spectroscopy: Recent Developments to Revolutionize Forensic Science  

Science Journals Connector (OSTI)

Vibrational Spectroscopy: Recent Developments to Revolutionize Forensic Science ... The National Academy of Sciences published a report outlining the current state of forensic science in the US, including issues being faced and necessary changes (National Research Council: Washington, D.C., 2009). ... These qualities, along with their automated capabilities, make Raman and IR spectroscopy model techniques according to the requirements outlined by the National Academy of Sciences. ...

Claire K. Luber; Kyle C Doty; Justin Bueno; Lenka Halamkova; Igor K. Lednev

2014-11-10T23:59:59.000Z

477

From chiral vibration to static chirality in ^{135}Nd  

E-Print Network (OSTI)

Electromagnetic transition probabilities have been measured for the intra- and inter-band transitions in the two sequences in the nucleus ^{135}Nd that were previously identified as a composite chiral pair of rotational bands. The measurements are in good agreement with results of a new combination of TAC and RPA calculations. The chiral character of the bands is affirmed and it is shown that their behavior is associated with a transition from a vibrational into a static chiral regime.

S. Mukhopadhyay; D. Almehed; U. Garg; S. Frauendorf; T. Li; P. V. Madhusudhana Rao; X. Wang; S. S. Ghugre; M. P. Carpenter; S. Gros; A. Hecht; R. V. F. Janssens; F. G. Kondev; T. Lauritsen; D. Seweryniak; S. Zhu

2007-08-10T23:59:59.000Z

478

Classical LQG's limitation and modification in stochastic vibration system  

E-Print Network (OSTI)

The function of control force is deduced by stochastic averaging method in shochastic vibration system.It is found that classical LQG is not full optimization because control force from displacement is of no effect to depress stochastic response.A modified vLQG control strategy is proposed . Numerical result shows that vLQG has better control effectiveness comparing with classical LQG control strategy.

Yinmiao Luo

2011-11-07T23:59:59.000Z

479

First observation of a near-harmonic vibrational nucleus  

Science Journals Connector (OSTI)

Evidence is presented for five closely spaced states in Cd118 near Eex?2 MeV, which are interpreted as a near-harmonic three-phonon quintuplet. Candidates for even higher-lying multiphonon states are also found. The experimental spectrum is compared with an anharmonic vibrator [or U(5) spectrum] and an interacting-boson-approximation calculation incorporating a two-particle, four-hole intruder configuration.

A. Aprahamian; D. S. Brenner; R. F. Casten; R. L. Gill; A. Piotrowski

1987-08-03T23:59:59.000Z

480

Video-based spatial portraits of a nonlinear vibrating string  

Science Journals Connector (OSTI)

The article describes a systematic experimental study of a string vibrating nonlinearly. The string is tracked in real time using strategically located cameras; the video tracking enables a remote observation of the oscillator without perturbing its inherent nonlinearities. We show that our technique can help probe the parametrically excited oscillations and study phenomena such as elliptical and circular trajectories near resonance resonance fold-over jump hysteresis and subharmonic resonance. The experiment has been successfully employed in the advanced physics laboratory.

Umer Hassan; Zubair Usman; Muhammad Sabieh Anwar

2012-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "random vibration environment" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


481

Geoscience/Environment  

NLE Websites -- All DOE Office Websites (Extended Search)

Geoscience/Environment Geoscience/Environment Geoscience/Environment Print From the high pressures at the Earth's core to the vacuum of outer space, the ALS has tools for investigating samples from either environmental extreme. "Geoscience" at the ALS covers a wide range of topics, from carbon sequestration and air quality to cometary composition and the formation of the solar system. To narrow the focus a bit, the ALS has an important role to play in addressing a number of environmental issues, including environmental remediation, hazardous-waste management, global climate change, agricultural sustainability, and trace-element cycling in ecosystems. These problems present major scientific challenges, in part because natural systems are extremely complex at a range of scales. Moreover, the behavior of these systems is determined by a complex interplay of chemical, physical, and biological processes in spatially heterogeneous environments. The ALS can contribute to the knowledge base needed to address a variety of environmental issues by enabling a variety of investigations, including analytical chemistry, microscopy of heterogeneous media, and reaction kinetics in natural systems.

482

ENVIRONMENT 2006 Annual Report  

E-Print Network (OSTI)

ENVIRONMENT 2006 Annual Report IBM AND THE #12;Table of Contents Global Environmental Management and Management 13 International Performance Measures 13 Water Conservation 15 Climate Protection 16 on environmental protection in 1971. The policy is supported by a comprehensive global environmental management

483

Multiprocessor programming environment  

SciTech Connect

Programming tools and techniques have been well developed for traditional uniprocessor computer systems. The focus of this research project is on the development of a programming environment for a high speed real time heterogeneous multiprocessor system, with special emphasis on languages and compilers. The new tools and techniques will allow a smooth transition for programmers with experience only on single processor systems.

Smith, M.B.; Fornaro, R.

1988-12-01T23:59:59.000Z

484

Collapse, environment, and society  

Science Journals Connector (OSTI)

...irrigable, Near Eastern desert environments. Multiple...turn the land over to desert, and renewed settlement requires...Spain, Mediterranean scrub (i.e., monte bajo...raise the water table of desert plains liable to salinization...while flushing soluble salts downstream. Egypt could...

Karl W. Butzer

2012-01-01T23:59:59.000Z

485

Gamifying intelligent environments  

Science Journals Connector (OSTI)

Recently digital designers have begun to integrate game elements and mechanics into non-game applications, systems, and services, to better engage end-users. This notion is named as the "gamification". In this paper, we discuss the idea of applying the ... Keywords: crowdsourcing, game-based motivation mechanism, gamification, intelligent environments, persuasive system, user engagement

Yefeng Liu; Todorka Alexandrova; Tatsuo Nakajima

2011-12-01T23:59:59.000Z

486

Noninvasive Monitoring of Vocal Fold Vertical Vibration Using The Acoustic Doppler Effect  

Science Journals Connector (OSTI)

SummaryObjectives/Hypothesis To validate a proposed method of noninvasively monitoring vocal fold vertical vibration through utilization of the acoustic Doppler effect and the waveguide property of the vocal tract. Study Design Validation case-control study. Methods In this device, an ultrasound beam is generated and directed into the mouth. The vocal tract, acting as a natural waveguide, guides the ultrasound beam toward the vibrating vocal folds. The vertical velocity of vocal fold vibration is then recovered from the Doppler frequency of the reflected ultrasound. One subject (age 32, male) was studied and measurements were taken under three modes of vocal fold vibration: breathing (no vibration), whispering (irregular vibration), and normal phonation (regular vibration). Results The peak-to-peak amplitude of the measured velocity of vocal fold vertical vibration was about 0.16 m/s, and the fundamental frequency was 172 Hz; the extracted velocity information showed a reasonable waveform and value in comparison with the previous studies. In all three modes of phonation, the Doppler frequencies derived from the reflected ultrasound corresponded with the vertical velocity of vocal fold vibration as expected. Conclusions The proposed method can accurately represent the characteristics of different phonation modes such as no phonation, whisper and normal phonation. The proposed device could be used in daily monitoring and assessment of vocal function and vocal fold vibration.

Chao Tao; Jack J. Jiang; Dan Wu; Xiaojun Liu; Ann Chodara

2012-01-01T23:59:59.000Z

487

Air spring vibration isolation technology for ship propulsion engine  

Science Journals Connector (OSTI)

Propulsion engine (PE) is one of the most dominant noise sources of ship. Due to the imposed requirement of keeping alignment with propulsion shaft during operation the effective vibration isolation of PE using low frequency mount is difficult to implement as is often adopted by other onboard machinery. In this paper a low frequency air spring vibration isolation system (ASVIS) with alignment control strategy for PE is conceived and introduced. The application of ASVIS to PE presents both advantages and challenges which are discussed detailedly in the paper as well as the feasibility of the ASVIS concept. A systematic design method of ASVIS for PE is established with focus on the system mechanical behavior optimization and automatic alignment control algorithm development. An ASVIS prototype is designed and manufactured using the proposed method. The performance of the prototype is tested by a series of experiments including alignment control precision and isolation efficiency. Experimental results show that using ASVIS the vibration of PE can be attenuated to a satisfactory level with the alignment between PE and shaft being maintained in the safe range.

He Lin; Xu Wei; Shuai Changgeng

2012-01-01T23:59:59.000Z

488

Betti numbers of random real hypersurfaces and determinants of random symmetric matrices  

E-Print Network (OSTI)

Betti numbers of random real hypersurfaces and determinants of random symmetric matrices Damien Betti numbers of random real hypersurfaces in smooth real projective manifolds. Our upper bounds grow get exponentially small away from mid-dimensional Betti numbers. In order to get these results, we

Paris-Sud XI, Université de

489

Hamilton Cycles Containing Randomly Selected Edges in Random Regular Graphs \\Lambda  

E-Print Network (OSTI)

Hamilton Cycles Containing Randomly Selected Edges in Random Regular Graphs \\Lambda R. W. Robinson oriented root edges have been randomly specified for the cycle to contain. The Hamilton cycle must be orientable to agree with all of the orientations on the j root edges. It is shown that the requisite Hamilton

Robinson, Robert W.

490

Measure, Randomness and Sublocales Alex Simpson  

E-Print Network (OSTI)

Measure, Randomness and Sublocales Alex Simpson Laboratory for Foundations of Computer Science, School of Informatics, University of Edinburgh, UK Abstract This paper investigates aspects of measure and randomness in the context of locale theory (point-free topology). We prove that every measure (-continuous

Simpson, Alex

491

Introduction to Network Science 1 Random Models  

E-Print Network (OSTI)

Introduction to Network Science 1 Random Models #12;Introduction to Network Science 2 mean degree in a graph with exactly m edges Taylor series reminder: #12;Introduction to Network Science 3 In contrast to the degree distribution in random model ... #12;Introduction to Network Science 4 In contrast to the degree

Safro, Ilya

492

Randomized Parallel Algorithms in Optimization Stephen Wright  

E-Print Network (OSTI)

Randomized Parallel Algorithms in Optimization Stephen Wright University of Wisconsin-Madison July 2013 Wright (UW-Madison) Random Parallel Optimization July 2013 1 / 52 #12;Collaborators @ UW-Madison Victor Bittorf Ji Liu Ben Recht ( Berkeley) Chris R´e ( Stanford) Krishna Sridhar Wright (UW

493

High speed optical quantum random number generation  

E-Print Network (OSTI)

High speed optical quantum random number generation Martin F¨urst1,2,, Henning Weier1,2, Sebastian, ready-for-use quantum random number generator (QRNG) whose stochastic model is based on the ran- domness directly delivered to a PC, generated at a rate of up to 50 Mbit/s, clearly pass all tests relevant

Weinfurter, Harald

494

Vibrational spectroscopy of the ammoniated ammonium ions NH sub 4 sup + (NH sub 3 ) sub n (n = 1-10)  

SciTech Connect

The gas-phase vibration-internal rotation spectra of mass-selected ammoniated ammonium ions, NH{sub 4}{sup +}(NH{sub 3}){sub n} (for n = 1-10), have been observed from 2600 to 4000 cm{sup {minus}1}. The spectra show vibrational features that have been assigned to modes involving both the ion core species, NH{sub 4}{sup +}, and the first shell NH{sub 3} solvent molecules. Nearly free internal rotation of the solvent molecules about their local C{sub 3} axes in the first solvation shell has been observed in the smaller clusters (n = 1-6). For the larger clusters studied (n = 7-10) the spectra converge, with little difference between clusters differing by one solvent molecule. For these clusters, the spectrum in the 3200-3500 cm{sup {minus}1} region is quite similar to that of liquid ammonia, and the entire region of 2600-3500 cm{sup {minus}1} also bears considerable resemblance to the spectra of ammonium salts dissolved in liquid ammonia under some chemical conditions. This indicates the onset of a liquidlike environment for the ion core and first shell solvent molecules in clusters as small as NH{sub 4}{sup +}(NH{sub 3}){sub 8}.

Price, J.M.; Crofton, M.W.; Lee, Y.T. (Lawrence Berkeley Lab., CA (United States) Univ. of California, Berkeley (United States))

1991-03-21T23:59:59.000Z

495

Solvent-side observation on vibrational energy transfer by transient grating spectroscopy: Bridged azulene-anthracene  

E-Print Network (OSTI)

Transient grating acoustic spectroscopy has been applied to studies on the vibrational energy relaxation process of the electronic ground state of azulene, two 1-alkylazulenes, and five bridged azulene-anthracenes in three different solvents: 1,1,1-trichloro-1,2,2-trifluoroethane, acetonitrile, and xenon. The solute molecule was vibrationally excited by the photo-excitation of the auzlenyl group to the S1 state through the fast internal conversion, and the rate of solvent thermalization due to the vibrational energy relaxation was determined. The thermalization rates for 1-alkylazulenes and bridged azulene-anthracenes were faster than that of azulene. Based on the results of the thermalization rates of 1-alkylazulenes, we concluded that the acceleration of the energy dissipation from the azulenyl group induced the faster energy dissipation from the solute to the solvent. The vibrational normal mode analysis suggests that the density of the vibrational modes and anharmonic coupling between the vibrational mode...

Fujiwara, Hiroki

2014-01-01T23:59:59.000Z

496

Environment and Protostellar Evolution  

E-Print Network (OSTI)

Even today in our Galaxy, stars form from gas cores in a variety of environments, which may affect the properties of resulting star and planetary systems. Here we study the role of pressure, parameterized via ambient clump mass surface density, on protostellar evolution and appearance, focussing on low-mass, Sun-like stars and considering a range of conditions from relatively low pressure filaments in Taurus, to intermediate pressures of cluster-forming clumps like the Orion Nebula Cluster (ONC), to very high pressures that may be found in the densest Infrared Dark Clouds (IRDCs) or in the Galactic Center (GC). We present unified analytic and numerical models for collapse of prestellar cores, accretion disks, protostellar evolution and bipolar outflows, coupled to radiative transfer (RT) calculations and a simple astrochemical model to predict CO gas phase abundances. Prestellar cores in high pressure environments are smaller and denser and thus collapse with higher accretion rates and efficiencies, resulting...

Zhang, Yichen

2014-01-01T23:59:59.000Z

497

Geoscience/Environment  

NLE Websites -- All DOE Office Websites (Extended Search)

Geoscience/Environment Print Geoscience/Environment Print From the high pressures at the Earth's core to the vacuum of outer space, the ALS has tools for investigating samples from either environmental extreme. "Geoscience" at the ALS covers a wide range of topics, from carbon sequestration and air quality to cometary composition and the formation of the solar system. To narrow the focus a bit, the ALS has an important role to play in addressing a number of environmental issues, including environmental remediation, hazardous-waste management, global climate change, agricultural sustainability, and trace-element cycling in ecosystems. These problems present major scientific challenges, in part because natural systems are extremely complex at a range of scales. Moreover, the behavior of these systems is determined by a complex interplay of chemical, physical, and biological processes in spatially heterogeneous environments. The ALS can contribute to the knowledge base needed to address a variety of environmental issues by enabling a variety of investigations, including analytical chemistry, microscopy of heterogeneous media, and reaction kinetics in natural systems.

498

The Effect of Whole Body Horizontal Vibration in Position Sense and Dynamic Stability of the Spine  

E-Print Network (OSTI)

of kneeling posture [10]. McGill et al. suggested that a fully- flexed spine results in lumbar extensor muscles ineffective to support anterior shear force, which is related to low back injury [11]. Standing and sitting have specific advantages... in flexed and asymmetric posture [79]. In another study, Arashanapalli et al. demonstrated the increased position sense error both during vibration exposure and instant after vibration exposure [76]. In addition, in a recent study of vibration induced...

Lamis, Farhana

2008-06-09T23:59:59.000Z

499

Influence of boundary conditions on 2-fluid Systems under horizontal vibration  

E-Print Network (OSTI)

This paper is concerned with 2-phase systems under vibration in gravity condition, when the gravity is perpendicular to the direction of vibration. It tries and demonstrates that, even in such a restricted case, the patterns which can be formed are very sensitive to the cell shape, to the boundary conditions and to the direction and the mode of vibration, i.e. linear, rotational,... Pacs # : 5.40 ; 45.70 ; 62.20 ; 83.70.Fn

P. Evesque

2005-06-20T23:59:59.000Z

500

Nanotechnology research facility? A vibration and noise control design case study  

Science Journals Connector (OSTI)

Vibration and noise control would be critical to the success of a proposed nanotechnology and molecular research facility. Roadway traffic a nearby power generation plant and buildings in the vicinity were potential sources of ground borne vibration disturbances. Mechanical equipment occupant installed support apparata and occupant activities were potential sources of internally generated vibration disturbances. On?site ground borne vibration was measured for comparison with generic floor vibration criteria for sensitive installations. Results were analyzed relative to criteria for potential disturbance of sensitive equipment perception by occupants audible radiated structure borne noise in acoustically sensitive spaces and resolution?degrading motion for scanning and for transmission electron microscopes and other nanotechnology clean room equipment. Design guidelines and structural vibration control concepts were recommended to the structural engineers including de?tuning damping and isolation methods. Recommendations were provided for mechanical noise control and vibration isolation. Architectural noise control sound isolation and room acoustics guidelines were provided for research office and meeting spaces. This case study will discuss the desired vibration and noise control objectives and the design solutions that were implemented. Building photographs will be presented. Post?construction measurement results will be graphically compared with pre?construction conditions to demonstrate apparent degree of success in mitigating vibration.

Jack B. Evans; Chad N. Himmel; Daniel J. Kupersztoch

2008-01-01T23:59:59.000Z