National Library of Energy BETA

Sample records for random number times

  1. Practical and fast quantum random number generation based on photon arrival time relative to external reference

    SciTech Connect (OSTI)

    Nie, You-Qi; Zhang, Jun Pan, Jian-Wei; Zhang, Hong-Fei; Wang, Jian; Zhang, Zhen; Ma, Xiongfeng

    2014-02-03

    We present a practical high-speed quantum random number generator, where the timing of single-photon detection relative to an external time reference is measured as the raw data. The bias of the raw data can be substantially reduced compared with the previous realizations. The raw random bit rate of our generator can reach 109 Mbps. We develop a model for the generator and evaluate the min-entropy of the raw data. Toeplitz matrix hashing is applied for randomness extraction, after which the final random bits are able to pass the standard randomness tests.

  2. Quantum random number generator

    E-Print Network [OSTI]

    M. Stipcevic; B. Medved Rogina

    2007-01-01

    We report upon a novel principle for realization of a fast nondeterministic random number generator whose randomness relies on intrinsic randomness of the quantum physical processes of photonic emission in semiconductors and subsequent detection by the photoelectric effect. Timing information of detected photons is used to generate binary random digits-bits. The bit extraction method based on restartable clock theoretically eliminates both bias and autocorrelation while reaching efficiency of almost 0.5 bits per random event. A prototype has been built and statistically tested.

  3. RNG: A Practitioner's Overview Random Number Generation

    E-Print Network [OSTI]

    Mascagni, Michael

    -Kac/path integral methods to solve partial differential equations with random walks Defense: neutronics, nuclear random numbers 1. Each calculation is a numerical experiment Subject to known and unknown sources a calculation with the same numbers Across different machines (modulo arithmetic issues) Parallel

  4. True random numbers from amplified quantum vacuum

    E-Print Network [OSTI]

    M. Jofre; M. Curty; F. Steinlechner; G. Anzolin; J. P. Torres; M. W. Mitchell; V. Pruneri

    2011-10-17

    Random numbers are essential for applications ranging from secure communications to numerical simulation and quantitative finance. Algorithms can rapidly produce pseudo-random outcomes, series of numbers that mimic most properties of true random numbers while quantum random number generators (QRNGs) exploit intrinsic quantum randomness to produce true random numbers. Single-photon QRNGs are conceptually simple but produce few random bits per detection. In contrast, vacuum fluctuations are a vast resource for QRNGs: they are broad-band and thus can encode many random bits per second. Direct recording of vacuum fluctuations is possible, but requires shot-noise-limited detectors, at the cost of bandwidth. We demonstrate efficient conversion of vacuum fluctuations to true random bits using optical amplification of vacuum and interferometry. Using commercially-available optical components we demonstrate a QRNG at a bit rate of 1.11 Gbps. The proposed scheme has the potential to be extended to 10 Gbps and even up to 100 Gbps by taking advantage of high speed modulation sources and detectors for optical fiber telecommunication devices.

  5. Random Numbers Certified by Bell's Theorem

    E-Print Network [OSTI]

    S. Pironio; A. Acin; S. Massar; A. Boyer de la Giroday; D. N. Matsukevich; P. Maunz; S. Olmschenk; D. Hayes; L. Luo; T. A. Manning; C. Monroe

    2010-10-19

    Randomness is a fundamental feature in nature and a valuable resource for applications ranging from cryptography and gambling to numerical simulation of physical and biological systems. Random numbers, however, are difficult to characterize mathematically, and their generation must rely on an unpredictable physical process. Inaccuracies in the theoretical modelling of such processes or failures of the devices, possibly due to adversarial attacks, limit the reliability of random number generators in ways that are difficult to control and detect. Here, inspired by earlier work on nonlocality based and device independent quantum information processing, we show that the nonlocal correlations of entangled quantum particles can be used to certify the presence of genuine randomness. It is thereby possible to design of a new type of cryptographically secure random number generator which does not require any assumption on the internal working of the devices. This strong form of randomness generation is impossible classically and possible in quantum systems only if certified by a Bell inequality violation. We carry out a proof-of-concept demonstration of this proposal in a system of two entangled atoms separated by approximately 1 meter. The observed Bell inequality violation, featuring near-perfect detection efficiency, guarantees that 42 new random numbers are generated with 99% confidence. Our results lay the groundwork for future device-independent quantum information experiments and for addressing fundamental issues raised by the intrinsic randomness of quantum theory.

  6. High speed optical quantum random number generation

    E-Print Network [OSTI]

    Weinfurter, Harald

    High speed optical quantum random number generation Martin F¨urst1,2,, Henning Weier1,2, Sebastian/publicationFile/30276/ais20 pdf.pdf (1999). 2. "Fips 140-2, security requirements for cryptographic modules

  7. Types of random numbers and Monte Carlo Methods Pseudorandom number generation

    E-Print Network [OSTI]

    Mascagni, Michael

    Types of random numbers and Monte Carlo Methods Pseudorandom number generation Quasirandom number generation Conclusions WE246: Random Number Generation A Practitioner's Overview Prof. Michael Mascagni #12;Types of random numbers and Monte Carlo Methods Pseudorandom number generation Quasirandom number

  8. Resolution-Stationary Random Number Generators

    E-Print Network [OSTI]

    L'Ecuyer, Pierre

    of successive output values over their entire period length. For F2-linear generators, the commonly adopted efficient ways of implementing high-quality and long-period Tausworthe generators. Key words: random number un [0, 1) is the output of the generator at step n and the number of bits in this output, L

  9. A self-testing quantum random number generator

    E-Print Network [OSTI]

    Tommaso Lunghi; Jonatan Bohr Brask; Charles Ci Wen Lim; Quentin Lavigne; Joseph Bowles; Anthony Martin; Hugo Zbinden; Nicolas Brunner

    2014-10-10

    A central issue in randomness generation is to estimate the entropy of the output data generated by a given device. Here we present a protocol for self-testing quantum random number generation, in which the entropy of the raw data can be monitored in real-time. In turn, this allows the user to adapt the randomness extraction procedure, in order to continuously generate high quality random bits. Using a fully optical implementation, we demonstrate that our protocol is practical and efficient, and illustrate its self-testing capacity.

  10. Maximization of Extractable Randomness in a Quantum Random-Number Generator

    E-Print Network [OSTI]

    J. Y. Haw; S. M. Assad; A. M. Lance; N. H. Y. Ng; V. Sharma; P. K. Lam; T. Symul

    2015-05-19

    The generation of random numbers via quantum processes is an efficient and reliable method to obtain true indeterministic random numbers that are of vital importance to cryptographic communication and large-scale computer modeling. However, in realistic scenarios, the raw output of a quantum random-number generator is inevitably tainted by classical technical noise. The integrity of the device can be compromised if this noise is tampered with, or even controlled by some malicious party. To safeguard against this, we propose and experimentally demonstrate an approach that produces side-information independent randomness that is quantified by min-entropy conditioned on this classical noise. We present a method for maximizing the conditional min-entropy of the number sequence generated from a given quantum-to-classical-noise ratio. The detected photocurrent in our experiment is shown to have a real-time random-number generation rate of 14 (Mbit/s)/MHz. The spectral response of the detection system shows the potential to deliver more than 70 Gbit/s of random numbers in our experimental setup.

  11. Robust quantum random number generator based on avalanche photodiodes

    E-Print Network [OSTI]

    Fang-Xiang Wang; Chao Wang; Wei Chen; Shuang Wang; Fu-Sheng Lv; De-Yong He; Zhen-Qiang Yin; Hong-Wei Li; Guang-Can Guo; Zheng-Fu Han

    2015-06-18

    We propose and demonstrate a scheme to realize a high-efficiency truly quantum random number generator (RNG) at room temperature (RT). Using an effective extractor with simple time bin encoding method, the avalanche pulses of avalanche photodiode (APD) are converted into high-quality random numbers (RNs) that are robust to slow varying noise such as fluctuations of pulse intensity and temperature. A light source is compatible but not necessary in this scheme. Therefor the robustness of the system is effective enhanced. The random bits generation rate of this proof-of-principle system is 0.69 Mbps with double APDs and 0.34 Mbps with single APD. The results indicate that a high-speed RNG chip based on the scheme is potentially available with an integrable APD array.

  12. Compact floating-gate true random number generator

    E-Print Network [OSTI]

    Maryland at College Park, University of

    Compact floating-gate true random number generator P. Xu, Y.L. Wong, T.K. Horiuchi and P.A. Abshire A compact true random number generator (RNG) integrated circuit with adjustable probability is presented. Introduction: Random number generation is indispensable in crypto- graphy, scientific computing and stochastic

  13. SPICE Simulation of a "Provably Secure" True Random Number Generator

    E-Print Network [OSTI]

    International Association for Cryptologic Research (IACR)

    SPICE Simulation of a "Provably Secure" True Random Number Generator Markus Dichtl, Bernd Meyer True Random Number Generator with Built-in Tolerance to Active Attacks", B. Sunar, W. Mar- tin, and D. Stinson propose a design for a true random number generator. Using SPICE simulation we study the behaviour

  14. Low-bias high-speed quantum random number generator via shaped optical pulses

    E-Print Network [OSTI]

    Kwiat, Paul

    Low-bias high-speed quantum random number generator via shaped optical pulses Michael A. Wayne generator (QRNG) based on the digitized time interval between random photon arrivals. By tailoring, secure quantum random number generation at rates exceeding 110 Mbit/s. ©2010 Optical Society of America

  15. Pseudo-random number generator based on asymptotic deterministic randomness

    E-Print Network [OSTI]

    Kai Wang; Wenjiang Pei; Haishan Xia; Yiu-ming Cheung

    2007-10-10

    An approach to generate the pseudorandom-bit sequence from the asymptotic deterministic randomness system is proposed in this Letter. We study the characteristic of multi-value correspondence of the asymptotic deterministic randomness constructed by the piecewise linear map and the noninvertible nonlinearity transform, and then give the discretized systems in the finite digitized state space. The statistic characteristics of the asymptotic deterministic randomness are investigated numerically, such as stationary probability density function and random-like behavior. Furthermore, we analyze the dynamics of the symbolic sequence. Both theoretical and experimental results show that the symbolic sequence of the asymptotic deterministic randomness possesses very good cryptographic properties, which improve the security of chaos based PRBGs and increase the resistance against entropy attacks and symbolic dynamics attacks.

  16. Analysis of the Linux Random Number Generator Zvi Gutterman

    E-Print Network [OSTI]

    International Association for Cryptologic Research (IACR)

    Analysis of the Linux Random Number Generator Zvi Gutterman Safend and The Hebrew University Abstract Linux is the most popular open source project. The Linux random number generator is part of the kernel of all Linux distributions and is based on generating randomness from entropy of operating system

  17. MIXMAX random number generator. Generalised parameters

    E-Print Network [OSTI]

    Savvidy, Konstantin

    2015-01-01

    We are exploring the parameter space of the MIXMAX random number generator, which is based on Kolmogorov-Anosov C-system defined on a torus. For a two-parameter family of C-system operators A(N,s), parametrised by the integers N and s, we found new larger values of N. One can deduce from this data that the entropy and the period are sharply increasing with N. For all of these parameters, the sequence passes all tests in the BigCrush suite. For the largest of them, N=44851, the period approaches million digits. The generator with N=256 and s=487013230256099064 has the best combination of speed, reasonable size of the state and availability for implementing the parallelisation and is currently the default generator in the ROOT software package at CERN. A three-parameter generator A(N,s,m) of the MIXMX family of generators is also presented, and it provides high quality statistical properties for small values of N.

  18. Chaotic generation of pseudo-random numbers 

    E-Print Network [OSTI]

    Dornbusch, Andrew Wesley

    1999-01-01

    Generation of repeatable pseudo-random sequences with chaotic analog electronics is not feasible using standard circuit topologies. Component variation caused by imperfect fabrication causes the same divergence of output ...

  19. Turing's normal numbers: towards randomness Veronica Becher

    E-Print Network [OSTI]

    presumably in 1938 Alan Turing gave an algorithm that produces real numbers normal to every integer base- putable normal numbers, and this result should be attributed to Alan Turing. His manuscript entitled "A

  20. Reducing the Cost of Generating APH-distributed Random Numbers

    E-Print Network [OSTI]

    Telek, Miklós

    Reducing the Cost of Generating APH-distributed Random Numbers Philipp Reinecke1 , Mikl´os Telek2 from PH distributions and propose two algorithms for reducing the cost associated with generating representation that minimises the cost associated with generating random numbers. In this paper we study

  1. True Random Number Generators Secure in a Changing Environment

    E-Print Network [OSTI]

    Shaltiel, Ronen

    , which is applied to the high­entropy source in order to obtain an output string that is shorterTrue Random Number Generators Secure in a Changing Environment Boaz Barak, Ronen Shaltiel, and Eran, ISRAEL Email: {boaz,ronens,tromer}@wisdom.weizmann.ac.il Abstract. A true random number generator (TRNG

  2. Noncolliding system of continuous-time random walks

    E-Print Network [OSTI]

    Syota Esaki

    2014-09-29

    The continuous-time random walk is defined as a Poissonization of discrete-time random walk. We study the noncolliding system of continuous-time simple and symmetric random walks on ${\\mathbb{Z}}$. We show that the system is determinantal for any finite initial configuration without multiple point. The spatio-temporal correlation kernel is expressed by using the modified Bessel functions. We extend the system to the noncolliding process with an infinite number of particles, when the initial configuration has equidistant spacing of particles, and show a relaxation phenomenon to the equilibrium determinantal point process with the sine kernel.

  3. Improving random number generators by chaotic Application in data hiding

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    the NIST (National Institute of Standards and Technology of the U.S. Government) battery of tests [10 battery of tests [8]. And its security is improved compared to XORshift alone, and to our former PRNG-random numbers in the field of data hiding is detailed. An analysis focuses on the watermarked images which have

  4. Random Matrix Spectra as a Time Series

    E-Print Network [OSTI]

    Ruben Fossion; Gamaliel Torres Vargas; Juan Carlos López Vieyra

    2013-11-23

    Spectra of ordered eigenvalues of finite Random Matrices are interpreted as a time series. Dataadaptive techniques from signal analysis are applied to decompose the spectrum in clearly differentiated trend and fluctuation modes, avoiding possible artifacts introduced by standard unfolding techniques. The fluctuation modes are scale invariant and follow different power laws for Poisson and Gaussian ensembles, which already during the unfolding allows to distinguish the two cases.

  5. Random Number Generation Using Amplified Spontaneous Emission in a Fiber Amplifier

    E-Print Network [OSTI]

    Anlage, Steven

    Random Number Generation Using Amplified Spontaneous Emission in a Fiber Amplifier Julia C. Salevan-random number generators ­ fast, but deterministic · Hardware-based random number generators · Atmospheric noise Random Excursions Random Excursions (var.)* Serial Linear Complexity p-value (uniformity) # of failures

  6. Quantum Statistical Testing of a Quantum Random Number Generator

    SciTech Connect (OSTI)

    Humble, Travis S

    2014-01-01

    The unobservable elements in a quantum technology, e.g., the quantum state, complicate system verification against promised behavior. Using model-based system engineering, we present methods for verifying the opera- tion of a prototypical quantum random number generator. We begin with the algorithmic design of the QRNG followed by the synthesis of its physical design requirements. We next discuss how quantum statistical testing can be used to verify device behavior as well as detect device bias. We conclude by highlighting how system design and verification methods must influence effort to certify future quantum technologies.

  7. A Pseudo-Random Number Generator for Spreadsheets Research Note, Jan 2013

    E-Print Network [OSTI]

    California at Berkeley, University of

    A Pseudo-Random Number Generator for Spreadsheets Research Note, Jan 2013 Michael Lampton, Space an experiment requires a generator of pseudo-random numbers. The function RAND built into popular spreadsheets instructor and student statistical results. Here, I introduce a well-tested random number generator

  8. Random Number Generation Using Amplified Spontaneous Emission in a Fiber Amplifier

    E-Print Network [OSTI]

    Anlage, Steven

    Random Number Generation Using Amplified Spontaneous Emission in a Fiber Amplifier Julia C. Salevan-speed, physical random number generator that can be implemented entirely in hardware. · Success in statistical and other interference · Scale system to multiple wavelengths · Random number generators (RNGs) have wide

  9. Bingo Voting: Secure and coercionfree voting using a trusted random number generator

    E-Print Network [OSTI]

    International Association for Cryptologic Research (IACR)

    Bingo Voting: Secure and coercion­free voting using a trusted random number generator Jens is based on a trusted random number generator. As a motivation for the new scheme two coercion/vote buying of a random number generator, comparable to a bingo cage. The new scheme achieves: -- ballot casting assurance

  10. Deep Random Search for Efficient Model Checking of Timed Automata

    E-Print Network [OSTI]

    Grosu, Radu

    Deep Random Search for Efficient Model Checking of Timed Automata R. Grosu1 , X. Huang1 , S}@imag.fr Abstract. We present DRS (Deep Random Search), a new Las Vegas algorithm for model checking safety fringe, which is the starting point of additional deep random walks. The DRS algorithm is complete

  11. Multi-bit quantum random number generation by measuring positions of arrival photons

    SciTech Connect (OSTI)

    Yan, Qiurong; Zhao, Baosheng; Liao, Qinghong; Zhou, Nanrun

    2014-10-15

    We report upon the realization of a novel multi-bit optical quantum random number generator by continuously measuring the arrival positions of photon emitted from a LED using MCP-based WSA photon counting imaging detector. A spatial encoding method is proposed to extract multi-bits random number from the position coordinates of each detected photon. The randomness of bits sequence relies on the intrinsic randomness of the quantum physical processes of photonic emission and subsequent photoelectric conversion. A prototype has been built and the random bit generation rate could reach 8 Mbit/s, with random bit generation efficiency of 16 bits per detected photon. FPGA implementation of Huffman coding is proposed to reduce the bias of raw extracted random bits. The random numbers passed all tests for physical random number generator.

  12. A finite-time exponent for random Ehrenfest gas

    E-Print Network [OSTI]

    Sanjay Moudgalya; Sarthak Chandra; Sudhir R. Jain

    2015-07-29

    We consider the motion of a system of free particles moving on a plane with regular hard polygonal scatterers arranged in a random manner. Calling this the Ehrenfest gas, which is known to have a zero Lyapunov exponent, we propose a finite-time exponent to characterize its dynamics. As the number of sides of the polygon goes to infinity, when polygon tends to a circle, we recover the usual Lyapunov exponent for the Lorentz gas from the exponent proposed here. To obtain this result, we generalize the reflection law of a beam of rays incident on a polygonal scatterer in a way that the formula for the circular scatterer is recovered in the limit of infinite number of vertices. Thus, chaos emerges from pseudochaos in an appropriate limit.

  13. How to Predict the Output of a Hardware Random Number Generator

    E-Print Network [OSTI]

    International Association for Cryptologic Research (IACR)

    How to Predict the Output of a Hardware Random Number Generator Markus Dichtl Siemens AG, Corporate Technology Email: Markus.Dichtl@siemens.com Abstract. A hardware random number generator was described at CHES 2002 in [Tka03]. In this paper, we analyze its method of generating randomness and

  14. Chaotic oscillation and random-number generation based on nanoscale optical-energy transfer

    E-Print Network [OSTI]

    Naruse, Makoto; Aono, Masashi; Hori, Hirokazu; Ohtsu, Motoichi

    2014-01-01

    By using nanoscale energy-transfer dynamics and density matrix formalism, we demonstrate theoretically and numerically that chaotic oscillation and random-number generation occur in a nanoscale system. The physical system consists of a pair of quantum dots (QDs), with one QD smaller than the other, between which energy transfers via optical near-field interactions. When the system is pumped by continuous-wave radiation and incorporates a timing delay between two energy transfers within the system, it emits optical pulses. We refer to such QD pairs as nano-optical pulsers (NOPs). Irradiating an NOP with external periodic optical pulses causes the oscillating frequency of the NOP to synchronize with the external stimulus. We find that chaotic oscillation occurs in the NOP population when they are connected by an external time delay. Moreover, by evaluating the time-domain signals by statistical-test suites, we confirm that the signals are sufficiently random to qualify the system as a random-number generator (R...

  15. Chaotic oscillation and random-number generation based on nanoscale optical-energy transfer

    E-Print Network [OSTI]

    Makoto Naruse; Song-Ju Kim; Masashi Aono; Hirokazu Hori; Motoichi Ohtsu

    2014-12-19

    By using nanoscale energy-transfer dynamics and density matrix formalism, we demonstrate theoretically and numerically that chaotic oscillation and random-number generation occur in a nanoscale system. The physical system consists of a pair of quantum dots (QDs), with one QD smaller than the other, between which energy transfers via optical near-field interactions. When the system is pumped by continuous-wave radiation and incorporates a timing delay between two energy transfers within the system, it emits optical pulses. We refer to such QD pairs as nano-optical pulsers (NOPs). Irradiating an NOP with external periodic optical pulses causes the oscillating frequency of the NOP to synchronize with the external stimulus. We find that chaotic oscillation occurs in the NOP population when they are connected by an external time delay. Moreover, by evaluating the time-domain signals by statistical-test suites, we confirm that the signals are sufficiently random to qualify the system as a random-number generator (RNG). This study reveals that even relatively simple nanodevices that interact locally with each other through optical energy transfer at scales far below the wavelength of irradiating light can exhibit complex oscillatory dynamics. These findings are significant for applications such as ultrasmall RNGs.

  16. A d-Sequence based Recursive Random Number Generator Abhishek Parakh

    E-Print Network [OSTI]

    International Association for Cryptologic Research (IACR)

    A d-Sequence based Recursive Random Number Generator Abhishek Parakh Louisiana State University number generators (RNGs) [4] in a manner analogous to the iterative squaring done in the BBS method [5,6]. In this paper we propose a new recursive technique for the use of d-sequences to generate random numbers

  17. Bad Estimates as a Function of Exceeding the MCNP Random Number Stride

    SciTech Connect (OSTI)

    Booth, Thomas E.

    2014-05-05

    Examples of bad MCNP estimates resulting from exceeding the MCNP random number stride are given for a simple infinite medium problem.

  18. Imaging and time reversal in random media Liliana Borcea

    E-Print Network [OSTI]

    Papanicolaou, George C.

    -separated scatterers in a randomly inhomogeneous environment using an active sensor array. The main features decomposition of the array response matrix in the frequency domain, and (iii) the construction of an objective of the medium. This is a new approach to array imaging that is motivated by time reversal in random media

  19. The random Schrödinger equation: homogenization in time-dependent potentials

    E-Print Network [OSTI]

    Yu Gu; Lenya Ryzhik

    2015-06-08

    We analyze the solutions of the Schr\\"odinger equation with the low frequency initial data and a time-dependent weakly random potential. We prove a homogenization result for the low frequency component of the wave field. We also show that the dynamics generates a non-trivial energy in the high frequencies, which do not homogenize -- the high frequency component of the wave field remains random and the evolution of its energy is described by a kinetic equation. The transition from the homogenization of the low frequencies to the random limit of the high frequencies is illustrated by understanding the size of the small random fluctuations of the low frequency component.

  20. Random numbers certified by Bell's theorem S. Pironio1,2

    E-Print Network [OSTI]

    Monroe, Christopher

    .Random numbers, however, are difficult to characterize mathematically1 , and their generation must rely on an unpredictable physical process2­6 . Inaccuracies in the theoretical modelling of such pro- cesses or failures of the devices, possibly due to adversarial attacks, limit the reliability of random number generators in ways

  1. Entropy of pseudo-random-number generators Stephan Mertens* and Heiko Bauke

    E-Print Network [OSTI]

    Mertens, Stephan

    , ... ,xi-q . Failure of these generators in clus- ter Monte Carlo simulations and related experiments canEntropy of pseudo-random-number generators Stephan Mertens* and Heiko Bauke Institut für)] some pseudo-random-number generators are known to yield wrong results in cluster Monte Carlo

  2. Time-Lock Puzzles from Randomized Encodings Nir Bitansky

    E-Print Network [OSTI]

    International Association for Cryptologic Research (IACR)

    Time-Lock Puzzles from Randomized Encodings Nir Bitansky Shafi Goldwasser Abhishek Jain Omer Paneth§ Vinod Vaikuntanathan¶ Brent Waters May 27, 2015 Abstract Time-lock puzzles, introduced by May, Rivest a puzzle with a solution s that remains hidden until a moderately large amount of time t has elapsed

  3. Imaging and time reversal in random media Liliana Borcea

    E-Print Network [OSTI]

    Tsogka, Chrysoula

    of small, well-separated scatterers in a randomly inhomogeneous environment using an active sensor array) the construction of an objective function in the time domain that is statistically stable and peaks individual realizations of the medium. This is a new approach to array imaging that is motivated by time

  4. Trading Infinite Memory for Uniform Randomness in Timed Games

    E-Print Network [OSTI]

    Henzinger, Thomas A.

    restriction on the game structure, and gives both players equally powerful options for advancing time specified as parity conditions. These games offer an appropriate model for the synthesis of real randomized real- time controllers are much simpler in structure than the corresponding pure controllers

  5. Trading Infinite Memory for Uniform Randomness in Timed Games #

    E-Print Network [OSTI]

    Henzinger, Thomas A.

    restriction on the game structure, and gives both players equally powerful options for advancing time objectives specified as parity conditions. These games o#er an appropriate model for the synthesis of real randomized real­ time controllers are much simpler in structure than the corresponding pure controllers

  6. Generation of fresh and pure random numbers for loophole-free Bell tests

    E-Print Network [OSTI]

    Carlos Abellan; Waldimar Amaya; Daniel Mitrani; Valerio Pruneri; Morgan W. Mitchell

    2015-06-08

    Quantum nonlocality is one of the most striking predictions to emerge from quantum theory, and has not been demonstrated unambiguously. Beyond its fundamental interest, a loophole-free Bell test would enable powerful "device independent" information protocols, guaranteed by the impossibility of faster-than-light communication. Current efforts to simultaneously close the detection, locality, and freedom of choice (FoC) loopholes require random number generation (RNG) with an unprecedented combination of speed, unpredictability, and confidence. Here we combine ultra-fast RNG by accelerated laser phase diffusion with real-time randomness extraction and metrological randomness assurances to produce a RNG suitable for loophole-free Bell tests. Under paranoid assumptions we infer error rates below 1e-8 at 5{\\sigma} statistical confidence for output based on spontaneous emission events less than 50 ns old. Tb- scale statistical analysis supports the metrological assessment of extreme unpredictability. The method will enable definitive nonlocality experiments and secure communications without need of trusted devices.

  7. Cryptanalysis of the Random Number Generator of the Windows Operating System

    E-Print Network [OSTI]

    International Association for Cryptologic Research (IACR)

    Cryptanalysis of the Random Number Generator of the Windows Operating System Leo Dorrendorf School by the Windows operating system is the most commonly used PRNG. The pseudo-randomness of the output the second most popular operating system after Windows XP. (This investigation was done without any help from

  8. Name: Section Number: TA Name: Section Time

    E-Print Network [OSTI]

    Wenzl, Hans

    carefully, answer each question completely, and show all of your work. Write your solutions clearly for the red light to turn green. The probability density function for x is given by p(x) = 1 40 if 0 x 40, 0 to turn green? (b) What is the median wait time for the red light to turn green? (c) What is the mean wait

  9. Robust random number generation using steady-state emission of gain-switched laser diodes

    SciTech Connect (OSTI)

    Yuan, Z. L. Lucamarini, M.; Dynes, J. F.; Fröhlich, B.; Plews, A.; Shields, A. J.

    2014-06-30

    We demonstrate robust, high-speed random number generation using interference of the steady-state emission of guaranteed random phases, obtained through gain-switching a semiconductor laser diode. Steady-state emission tolerates large temporal pulse misalignments and therefore significantly improves the interference quality. Using an 8-bit digitizer followed by a finite-impulse-response unbiasing algorithm, we achieve random number generation rates of 8 and 20?Gb/s, for laser repetition rates of 1 and 2.5?GHz, respectively, with a ±20% tolerance in the interferometer differential delay. We also report a generation rate of 80?Gb/s using partially phase-correlated short pulses. In relation to the field of quantum key distribution, our results confirm the gain-switched laser diode as a suitable light source, capable of providing phase-randomized coherent pulses at a clock rate of up to 2.5?GHz.

  10. Continuous time random walk models for fractional space-time diffusion equations

    E-Print Network [OSTI]

    Sabir Umarov

    2014-09-14

    In this paper continuous time random walk models approximating fractional space-time diffusion processes are studied. Stochastic processes associated with the considered equations represent time-changed processes, where the time-change process is a L\\'evy's stable subordinator with the stability index $\\beta \\in (0,1).$ In the parer the convergence of constructed CTRWs to time-changed processes associated with the corresponding fractional diffusion equations are proved using a new analytic method.

  11. An On-Demand Optical Quantum Random Number Generator with In-Future Action and Ultra-Fast Response

    E-Print Network [OSTI]

    Mario Stip?evi?; Rupert Ursin

    2015-06-09

    Random numbers are essential for our modern information based society e.g. in cryptography. Unlike frequently used pseudo-random generators, physical random number generators do not depend on complex algorithms but rather on a physical process to provide true randomness. Quantum random number generators (QRNG) do rely on a process, which can be described by a probabilistic theory only, even in principle. Here we present a conceptually simple implementation, which offers a 100% efficiency of producing a random bit upon a request and simultaneously exhibits an ultra low latency. A careful technical and statistical analysis demonstrates its robustness against imperfections of the actual implemented technology and enables to quickly estimate randomness of very long sequences. Generated random numbers pass standard statistical tests without any post-processing. The setup described, as well as the theory presented here, demonstrate the maturity and overall understanding of the technology.

  12. A Study of Entropy Sources in Cloud Random Number Generation on Cloud Hosts

    E-Print Network [OSTI]

    Chen, Yu

    A Study of Entropy Sources in Cloud Computers: Random Number Generation on Cloud Hosts Brendan Kerrigan and Yu Chen Dept. of Electrical and Computer Engineering, SUNY - Binghamton Abstract. Cloud security practices are based on assumptions that hold true for physical machines, but don't translate

  13. Good random number generators are (not so) easy to find P. Hellekalek*

    E-Print Network [OSTI]

    Palmeri, Thomas

    criteria for good random number generators: theoretical support, empirical evidence and practical aspects refer to Section 4 and Section 5. In this paper, safety-measures against such unpleasant surprises #12;A good generator is not so easy to find if one sets out to design it by oneself, without

  14. Continuous Time Random Walk and Migration Proliferation Dichotomy

    E-Print Network [OSTI]

    A. Iomin

    2015-04-03

    A theory of fractional kinetics of glial cancer cells is presented. A role of the migration-proliferation dichotomy in the fractional cancer cell dynamics in the outer-invasive zone is discussed an explained in the framework of a continuous time random walk. The main suggested model is based on a construction of a 3D comb model, where the migration-proliferation dichotomy becomes naturally apparent and the outer-invasive zone of glioma cancer is considered as a fractal composite with a fractal dimension $\\frD<3$.

  15. Oracle inequalities for SVMs that are based on random entropy numbers

    SciTech Connect (OSTI)

    Steinwart, Ingo

    2009-01-01

    In this paper we present a new technique for bounding local Rademacher averages of function classes induced by a loss function and a reproducing kernel Hilbert space (RKHS). At the heart of this technique lies the observation that certain expectations of random entropy numbers can be bounded by the eigenvalues of the integral operator associated to the RKHS. We then work out the details of the new technique by establishing two new oracle inequalities for SVMs, which complement and generalize orevious results.

  16. 462 IEEE TRANSACTIONS ON INFORMATION THEORY, VOL. 44, NO. 2, MARCH 1998 Source Codes as Random Number Generators

    E-Print Network [OSTI]

    Kulkarni, Sanjeev

    ´u [11] gave fundamental limits on the rate at which random bits can be generated from an arbitrary Number Generators Karthik Visweswariah, Student Member, IEEE, Sanjeev R. Kulkarni, Senior Member, IEEE, and Sergio Verd´u, Fellow, IEEE Abstract--A random number generator generates fair coin flips by processing

  17. Topological relics of symmetry breaking: Winding numbers and scaling tilts from random vortex-antivortex pairs

    E-Print Network [OSTI]

    Wojciech H. Zurek

    2014-10-01

    I show that random distributions of vortex-antivortex pairs (rather than of individual vortices) lead to scaling of typical winding numbers W trapped inside a loop of circumference C with the square root of C when the expected winding numbers are large. Such scaling is consistent with the Kibble-Zurek mechanism (KZM). By contrast, distribution of individual vortices with randomly assigned topological charges would result in the dispersion of W scaling with the square root of the area inside C. Scaling of the dispersion of W and of the probability of detection of non-zero W with C can be also studied for loops so small that non-zero windings are rare. In this case I show a doubling of the scaling of dispersion with C when compared to the scaling of dispersion in the large W regime. Moreover, probability of trapping of a non-zero W becomes, in this case, proportional to the area subtended by C (hence, to the square of circumference). This quadruples, as compared with large winding numbers regime, the exponent in the power law dependence of the frequency of trapping of W=+1 or W=-1 on C. Such change of the power law exponent by a FACTOR OF FOUR implies quadrupling of the scaling of the frequency of winding number trapping with the quench rate, and is of key importance for experimental tests of KZM.

  18. An N Server Cutoff Priority Queue Where Customers Request a Random Number of Servers

    E-Print Network [OSTI]

    Schaack, Christian

    Consider a multi-priority, nonpreemptive, N-server Poisson arrival queueing system. The number of servers requested by an arrival has a known probability distribution. Service times are negative exponential. In order to ...

  19. Post-Processing Free Spatio-Temporal Optical Random Number Generator Resilient to Hardware Failure and Signal Injection Attacks

    E-Print Network [OSTI]

    Mario Stip?evi?; John Bowers

    2014-10-09

    We present a random number generator based on quantum effects in photonic emission and detection. It is unique in simultaneous use of both spatial and temporal quantum information contained in the system which makes it resilient to hardware failure and signal injection attacks. We show that its deviation from randomness cam be estimated based on simple measurements. Generated numbers pass NIST Statistical test suite without post-processing.

  20. The cover time of sparse random graphs. Colin Cooper

    E-Print Network [OSTI]

    Cooper, Colin

    that CG n log n log log n. The challenge is to find a technique which can make an accurate average case) 2|E(H)| is the steady state of a random walk on H. NG(v) is the set of neighbours of v in G. If H

  1. An elementary derivation of first and last return times of 1D random walks

    E-Print Network [OSTI]

    Kostinski, Sarah

    2015-01-01

    Random walks, and in particular, their first passage times, are ubiquitous in nature. Using direct enumeration of paths, we find the first return time distribution of a 1D random walker, which is a heavy-tailed distribution with infinite mean. Using the same method we find the last return time distribution, which follows the arcsine law. Both results have a broad range of applications in physics and other disciplines. The derivation presented here is readily accessible to physics undergraduates, and provides an elementary introduction into random walks and their intriguing properties.

  2. Joint asymptotic behavior of local and occupation times of random walk in higher dimension

    E-Print Network [OSTI]

    Csáki, Endre

    Joint asymptotic behavior of local and occupation times of random walk in higher dimension Endre behavior of two objects: #28;rst the local times of a pair of neighboring points, then the local time of a point and the occupation time of the surface of the unit ball around it. AMS 2000 Subject Classi#28

  3. Lifetime, turnover time, and fast magnetic field regeneration in random flows

    SciTech Connect (OSTI)

    Tanner, S. E. M. [School of Mathematical Sciences, Dublin City University, Dublin 9 (Ireland)

    2007-10-15

    The fast dynamo is thought to be relevant in the regeneration of magnetic fields in astrophysics where the value of the magnetic Reynolds number (Rm) is immense. The fast dynamo picture is one in which chaotic flows provide a mechanism for the stretching of magnetic field lines. Furthermore, a cascade of energy down to small scales results in intermittent regions of a small-scale, intense magnetic field. Given this scenario it is natural to invoke the use of kinematic random flows in order to understand field regeneration mechanisms better. Here a family of random flows is used to study the effects that L, the lifetime of the cell, and {tau}, the turnover time of the cell, may have on magnetic field regeneration. Defining the parameter {gamma}=L/{tau}, it has been varied according to {gamma}>1, {gamma}<1, {gamma}{approx}O(1). In the kinematic regime, dynamo growth rates and Lyapunov exponents are examined at varying values of Rm. The possibility of fast dynamo action is considered. In the nonlinear regime, magnetic and kinetic energies are examined. Results indicate that there does appear to be a relationship between {gamma} and dynamo efficiency. In particular, the most efficient dynamos seem to operate at lower values of {gamma}.

  4. Packet acquisition for time-frequency hopped asynchronous random multiple access

    E-Print Network [OSTI]

    Nguyen, Hoang

    Packet acquisition for a time-frequency hopped asynchronous random multiple access (RMA) system is investigated. A novel analytical approach to performance evaluation is provided, which enables the waveform designer to ...

  5. Statistical Stability and Time-Reversal Imgaing in Random Media

    SciTech Connect (OSTI)

    Berryman, J; Borcea, L; Papanicolaou, G; Tsogka, C

    2002-02-05

    Localization of targets imbedded in a heterogeneous background medium is a common problem in seismic, ultrasonic, and electromagnetic imaging problems. The best imaging techniques make direct use of the eigenfunctions and eigenvalues of the array response matrix, as recent work on time-reversal acoustics has shown. Of the various imaging functionals studied, one that is representative of a preferred class is a time-domain generalization of MUSIC (MUltiple Signal Classification), which is a well-known linear subspace method normally applied only in the frequency domain. Since statistical stability is not characteristic of the frequency domain, a transform back to the time domain after first diagonalizing the array data in the frequency domain takes optimum advantage of both the time-domain stability and the frequency-domain orthogonality of the relevant eigenfunctions.

  6. Emergence of randomness and arrow of time in quantum walks

    E-Print Network [OSTI]

    Shikano, Yutaka

    Quantum walks are powerful tools not only for constructing the quantum speedup algorithms but also for describing specific models in physical processes. Furthermore, the discrete time quantum walk has been experimentally ...

  7. The B-Exponential Map: A Generalization of the Logistic Map, and Its Applications In Generating Pseudo-random Numbers

    E-Print Network [OSTI]

    Mahesh C Shastry; Nithin Nagaraj; Prabhakar G Vaidya

    2006-07-17

    A 1-dimensional generalization of the well known Logistic Map is proposed. The proposed family of maps is referred to as the B-Exponential Map. The dynamics of this map are analyzed and found to have interesting properties. In particular, the B-Exponential Map exhibits robust chaos for all real values of the parameter B >= e^(-4). We then propose a pseudo-random number generator based on the B-Exponential Map by chaotically hopping between different trajectories for different values of B. We call this BEACH (B-Exponential All-Chaotic Map Hopping) pseudo-random number generator. BEACH successfully passes stringent statistical randomness tests such as ENT, NIST and Diehard. An implementation of BEACH is also outlined.

  8. Number of first-passage times as a measurement of information for weakly chaotic systems

    E-Print Network [OSTI]

    Pierre Nazé; Roberto Venegeroles

    2014-10-21

    We consider a general class of maps of the interval having Lyapunov subexponential instability $|\\delta x_{t}|\\sim|\\delta x_{0}|\\exp[\\Lambda_{t}(x_{0})\\zeta(t)]$, where $\\zeta(t)$ grows sublinearly as $t\\rightarrow\\infty$. We outline here a scheme [J. Stat. Phys. {\\bf 154}, 988 (2014)] whereby the choice of a characteristic function automatically defines the map equation and corresponding growth rate $\\zeta(t)$. This matching approach is based on the infinite measure property of such systems. We show that the average information that is necessary to record without ambiguity a trajectory of the system tends to $\\langle\\Lambda\\rangle\\zeta(t)$, suitably extending the Kolmogorov-Sinai entropy and Pesin's identity. For such systems, information behaves like a random variable for random initial conditions, its statistics obeying a universal Mittag-Leffler law. We show that, for individual trajectories, information can be accurately inferred by the number of first-passage times through a given turbulent phase space cell. This enables us to calculate far more efficiently Lyapunov exponents for such systems. Lastly, we also show that the usual renewal description of jumps to the turbulent cell, usually employed in the literature, does not provide the real number of entrances there. Our results are supported by exhaustive numerical simulations.

  9. Imaging and time reversal in random media Liliana Borcea # George Papanicolaou + Chrysoula Tsogka # James Berryman

    E-Print Network [OSTI]

    Papanicolaou, George C.

    , well­separated scatterers in a randomly inhomogeneous environment using an active sensor array) the construction of an objective function in the time domain that is statistically stable and peaks individual realizations of the medium. This is a new approach to array imaging that is motivated by time

  10. Integrating Random Matrix Theory Predictions with Short-Time Dynamical Effects in Chaotic Systems

    E-Print Network [OSTI]

    A. Matthew Smith; Lev Kaplan

    2010-06-29

    We discuss a modification to Random Matrix Theory eigenstate statistics, that systematically takes into account the non-universal short-time behavior of chaotic systems. The method avoids diagonalization of the Hamiltonian, instead requiring only a knowledge of short-time dynamics for a chaotic system or ensemble of similar systems. Standard Random Matrix Theory and semiclassical predictions are recovered in the limits of zero Ehrenfest time and infinite Heisenberg time, respectively. As examples, we discuss wave function autocorrelations and cross-correlations, and show that significant improvement in accuracy is obtained for simple chaotic systems where comparison can be made with brute-force diagonalization. The accuracy of the method persists even when the short-time dynamics of the system or ensemble is known only in a classical approximation. Further improvement in the rate of convergence is obtained when the method is combined with the correlation function bootstrapping approach introduced previously.

  11. MOMENTS OF THE TRANSMISSION EIGENVALUES, PROPER DELAY TIMES AND RANDOM MATRIX THEORY I

    E-Print Network [OSTI]

    Mezzadri, Francesco

    to the moments of the transmission eigenvalues of the electric current through a ballistic cavity; the negativeMOMENTS OF THE TRANSMISSION EIGENVALUES, PROPER DELAY TIMES AND RANDOM MATRIX THEORY I F. MEZZADRI of the transmission eigenvalues of an electron through a quantum dot with chaotic dynamics. For the Laguerre ensemble

  12. The limit of small Rossby numbers for randomly forced quasi-geostrophic equation on $?$-plane

    E-Print Network [OSTI]

    Sergei Kuksin; Alberto Maiocchi

    2014-09-26

    We consider the 2d quasigeostrophic equation on the $\\beta$-plane for the stream function $\\psi$, with dissipation and a random force: $$ (*)\\qquad (-\\Delta +K)\\psi_t - \\rho J(\\psi, \\Delta\\psi) -\\beta\\psi_x= \\langle \\text{random force}\\rangle -\\kappa\\Delta^2\\psi +\\Delta\\psi, $$ where $\\psi=\\psi(t,x,y), \\ x\\in\\mathbb{R}/2\\pi L\\mathbb{Z}, \\ y\\in \\mathbb{R}/2\\pi \\mathbb{Z}$. For typical values of the horizontal period $L$ we prove that the law of the action-vector of a solution for $(*)$ (formed by the halves of the squared norms of its complex Fourier coefficients) converges, as $\\beta\\to\\infty$, to the law of an action-vector for solution of an auxiliary effective equation, and the stationary distribution of the action-vector for solutions of $(*)$ converges to that of the effective equation. Moreover, this convergence is uniform in $\\kappa\\in(0,1]$. The effective equation is an infinite system of stochastic equations which splits into invariant subsystems of complex dimension $\\le3$; each of these subsystems is an integrable hamiltonian system, coupled with a Langevin thermostat. Under the iterated limits $\\lim_{L=\\rho\\to\\infty} \\lim_{\\beta\\to\\infty}$ and $\\lim_{\\kappa\\to 0} \\lim_{\\beta\\to\\infty}$ we get similar systems. In particular, none of the three limiting systems exhibits the energy cascade to high frequencies.

  13. PHYSICAL REVIEW E 84, 061143 (2011) Asymptotic solutions of decoupled continuous-time random walks with superheavy-tailed waiting

    E-Print Network [OSTI]

    Lindenberg, Katja

    2011-01-01

    -time behavior of decoupled continuous-time random walks characterized by superheavy- tailed distributions of jump processes that are widely used to model a variety of physical, geological, biological, economic

  14. Dynamic Response of an Optomechanical System to a Stationary Random Excitation in the Time Domain

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Palmer, Jeremy A.; Paez, Thomas L.

    2011-01-01

    Modern electro-optical instruments are typically designed with assemblies of optomechanical members that support optics such that alignment is maintained in service environments that include random vibration loads. This paper presents a nonlinear numerical analysis that calculates statistics for the peak lateral response of optics in an optomechanical sub-assembly subject to random excitation of the housing. The work is unique in that the prior art does not address peak response probability distribution for stationary random vibration in the time domain for a common lens-retainer-housing system with Coulomb damping. Analytical results are validated by using displacement response data from random vibration testingmore »of representative prototype sub-assemblies. A comparison of predictions to experimental results yields reasonable agreement. The Type I Asymptotic form provides the cumulative distribution function for peak response probabilities. Probabilities are calculated for actual lens centration tolerances. The probability that peak response will not exceed the centration tolerance is greater than 80% for prototype configurations where the tolerance is high (on the order of 30 micrometers). Conversely, the probability is low for those where the tolerance is less than 20 micrometers. The analysis suggests a design paradigm based on the influence of lateral stiffness on the magnitude of the response.« less

  15. Semi-Markov approach to continuous time random walk limit processes

    E-Print Network [OSTI]

    Meerschaert, Mark M

    2014-01-01

    Continuous time random walks (CTRWs) are versatile models for anomalous diffusion processes that have found widespread application in the quantitative sciences. Their scaling limits are typically non-Markovian, and the computation of their finite-dimensional distributions is an important open problem. This paper develops a general semi-Markov theory for CTRW limit processes in $\\mathbb{R}^d$ with infinitely many particle jumps (renewals) in finite time intervals. The particle jumps and waiting times can be coupled and vary with space and time. By augmenting the state space to include the scaling limits of renewal times, a CTRW limit process can be embedded in a Markov process. Explicit analytic expressions for the transition kernels of these Markov processes are then derived, which allow the computation of all finite dimensional distributions for CTRW limits. Two examples illustrate the proposed method.

  16. DESIGNING A REAL TIME SYSTEM FOR CAR NUMBER DETECTION USING DISCRETE HOPFIELD NETWORK

    E-Print Network [OSTI]

    Mishra, Prabhat

    DESIGNING A REAL TIME SYSTEM FOR CAR NUMBER DETECTION USING DISCRETE HOPFIELD NETWORK A.BANERJEE1@yahoo.co.in Abstract The paper addresses a novel scheme for detection of car numbers from its rear end number plates. The work has extensive applications in automatic identification of cars, responsible for Cox pollution

  17. Frequency decoding of periodically timed action potentials through distinct activity patterns in a random neural network

    E-Print Network [OSTI]

    Reichenbach, Tobias

    2015-01-01

    Frequency discrimination is a fundamental task of the auditory system. The mammalian inner ear, or cochlea, provides a place code in which different frequencies are detected at different spatial locations. However, a temporal code based on spike timing is also available: action potentials evoked in an auditory-nerve fiber by a low-frequency tone occur at a preferred phase of the stimulus-they exhibit phase locking-and thus provide temporal information about the tone's frequency. In an accompanying psychoacoustic study, and in agreement with previous experiments, we show that humans employ this temporal information for discrimination of low frequencies. How might such temporal information be read out in the brain? Here we demonstrate that recurrent random neural networks in which connections between neurons introduce characteristic time delays, and in which neurons require temporally coinciding inputs for spike initiation, can perform sharp frequency discrimination when stimulated with phase-locked inputs. Alt...

  18. Self-intersection local times of random walks: Exponential moments in subcritical dimensions

    E-Print Network [OSTI]

    Becker, Mathias

    2010-01-01

    Fix $p>1$, not necessarily integer, with $p(d-2)0$ that are bounded from above, possibly tending to zero. The speed is identified in terms of mixed powers of $t$ and $\\theta_t$, and the precise rate is characterized in terms of a variational formula, which is in close connection to the {\\it Gagliardo-Nirenberg inequality}. As a corollary, we obtain a large-deviation principle for $\\|\\ell_t\\|_p/(t r_t)$ for deviation functions $r_t$ satisfying $t r_t\\gg\\E[\\|\\ell_t\\|_p]$. Informally, it turns out that the random walk homogeneously squeezes in a $t$-dependent box with diameter of order $\\ll t^{1/d}$ to produce the required amount of self-intersections. Our main tool is an upper bound for the joint density of the local times of the walk.

  19. Space-Time as an Orderparameter Manifold in Random Networks and the Emergence of Physical Points

    E-Print Network [OSTI]

    Manfred Requardt

    1999-02-11

    In the following we are going to describe how macroscopic space-time is supposed to emerge as an orderparameter manifold or superstructure floating in a stochastic discrete network structure. As in preceeding work (mentioned below), our analysis is based on the working philosophy that both physics and the corresponding mathematics have to be genuinely discrete on the primordial (Planck scale) level. This strategy is concretely implemented in the form of cellular networks and random graphs. One of our main themes is the development of the concept of physical (proto)points as densely entangled subcomplexes of the network and their respective web, establishing something like (proto)causality. It max perhaps be said that certain parts of our programme are realisations of some old and qualitative ideas of Menger and more recent ones sketched by Smolin a couple of years ago. We briefly indicate how this two-story-concept of space-time can be used to encode the (at least in our view) existing non-local aspects of quantum theory without violating macroscopic space-time causality!

  20. (Quantum) Space-Time as a Statistical Geometry of Lumps in Random Networks

    E-Print Network [OSTI]

    Manfred Requardt

    1999-12-15

    In the following we undertake to describe how macroscopic space-time (or rather, a microscopic protoform of it) is supposed to emerge as a superstructure of a web of lumps in a stochastic discrete network structure. As in preceding work (mentioned below), our analysis is based on the working philosophy that both physics and the corresponding mathematics have to be genuinely discrete on the primordial (Planck scale) level. This strategy is concretely implemented in the form of \\tit{cellular networks} and \\tit{random graphs}. One of our main themes is the development of the concept of \\tit{physical (proto)points} or \\tit{lumps} as densely entangled subcomplexes of the network and their respective web, establishing something like \\tit{(proto)causality}. It may perhaps be said that certain parts of our programme are realisations of some early ideas of Menger and more recent ones sketched by Smolin a couple of years ago. We briefly indicate how this \\tit{two-story-concept} of \\tit{quantum} space-time can be used to encode the (at least in our view) existing non-local aspects of quantum theory without violating macroscopic space-time causality.

  1. Radio Science, Volume ???, Number , Pages 110, Time Reversal of Electromagnetic Waves and

    E-Print Network [OSTI]

    Paris 7 - Denis Diderot, Université

    electromagnetic pulse at a central frequency of 2.45 GHz in a high-Q cavity. Another antenna records the stronglyRadio Science, Volume ???, Number , Pages 1­10, Time Reversal of Electromagnetic Waves demonstration of time-reversal focusing with electromagnetic waves in a SISO scheme. An antenna transmits a 1 µs

  2. Finite-time rotation number: a fast indicator for chaotic dynamical structures

    E-Print Network [OSTI]

    J. D. Szezech Jr.; A. B. Schelin; I. L. Caldas; S. R. Lopes; P. J. Morrison; R. L. Viana

    2011-02-10

    Lagrangian coherent structures are effective barriers, sticky regions, that separate phase space regions of different dynamical behavior. The usual way to detect such structures is via finite-time Lyapunov exponents. We show that similar results can be obtained for single-frequency systems from finite-time rotation numbers, which are much faster to compute. We illustrate our claim by considering examples of continuous and discrete-time dynamical systems of physical interest.

  3. A Cascade Method for Reducing Training Time and the Number of Support Vectors

    E-Print Network [OSTI]

    Lu, Bao-Liang

    subproblems and to parallelly learn these subproblems by many modules. After training, all the trained modulesA Cascade Method for Reducing Training Time and the Number of Support Vectors Yi-Min Wen1,2 and Bao 400052, China Abstract. A novel cascade learning strategy for training support vec- tor machines (SVMs

  4. The question of randomness in English foot timing: a control experiment 

    E-Print Network [OSTI]

    Williams, Briony

    1994-01-01

    Isochrony has been considered only in terms of stressed syllables. However, it may also be a random property of unstressed syllables, and a control experiment was deemed necessary. A handtranscribed database of 98 sentences, ...

  5. CM165A-01 ACM-TRANSACTION September 15, 2003 16:34 Efficient Multiply-with-Carry Random Number

    E-Print Network [OSTI]

    Goresky, Mark

    P1: GDP CM165A-01 ACM-TRANSACTION September 15, 2003 16:34 Efficient Multiply-with-Carry Random. Copyrights for components of this work owned by others than ACM must be honored. Abstracting with credit be requested from Publications Dept., ACM, Inc., 1515 Broadway, New York, NY 10036 USA, fax: +1 (212) 869

  6. Fig. 1. Comparison of search times on original logistics problems. Fig 2. Number of variables in logistics formulas after simplification.

    E-Print Network [OSTI]

    Kautz, Henry

    Fig. 1. Comparison of search times on original logistics problems. Fig 2. Number of variables in logistics formulas after simplification. Fig. 3. Number of clauses in logistics formulas after number of clauses log.a log.b log.c #12; Fig. 4: Solution times for walksat on logistics with different

  7. Time splitting for the Liouville equation in a random medium Guillaume Bal

    E-Print Network [OSTI]

    Ryzhik, Lenya

    communication, acoustic waves in underwater communication, and seismic waves generated by earthquakes [5, 12, 17, 18]. Here we consider propagation of high frequency acoustic waves. Wave propagation in such a regime can be approximated by a Liouville equation with random potential for the acoustic energy density

  8. Time splitting for the Liouville equation in a random medium Guillaume Bal

    E-Print Network [OSTI]

    Bal, Guillaume

    communication, acoustic waves in underwater communication, and seismic waves generated by earthquakes [6, 14, 18, 19]. Here we consider propagation of high frequency acoustic waves. Wave propagation in such a regime can be approximated by a Liouville equation with random potential for the acoustic energy density

  9. Space and time dependent scaling of numbers in mathematical structures: Effects on physical and geometric quantities

    E-Print Network [OSTI]

    Paul Benioff

    2015-08-07

    The relationship between the foundations of mathematics and physics is a topic of of much interest. This paper continues this exploration by examination of the effect of space and time dependent number scaling on theoretical descriptions of some physical and geometric quantities. Fiber bundles provide a good framework to introduce a space and time or space time dependent number scaling field. The effect of the scaling field on a few nonlocal physical and geometric quantities is described. The effect on gauge theories is to introduce a new complex scalar field into the derivatives appearing in Lagrangians. U(1) invariance of Lagrangian terms does not affect the real part of the scaling field. For this field, any mass is possible. The scaling field is also shown to affect quantum wave packets and path lengths, and geodesic equations even on flat space. Scalar fields described so far in physics, are possible candidates for the scaling field. The lack of direct evidence for the field in physics restricts the scaling field in that the gradient of the field must be close to zero in a local region of cosmological space and time. There are no restrictions outside the region. It is also seen that the scaling field does not affect comparisons of computation or measurements outputs with one another. However it does affect the assignment of numerical values to the outputs of computations or measurements. These are needed because theory predictions are in terms of numerical values.

  10. (Quantum) Space-Time as a Statistical Geometry of Fuzzy Lumps and the Connection with Random Metric Spaces

    E-Print Network [OSTI]

    Manfred Requardt; Sisir Roy

    2001-02-13

    We develop a kind of pregeometry consisting of a web of overlapping fuzzy lumps which interact with each other. The individual lumps are understood as certain closely entangled subgraphs (cliques) in a dynamically evolving network which, in a certain approximation, can be visualized as a time-dependent random graph. This strand of ideas is merged with another one, deriving from ideas, developed some time ago by Menger et al, that is, the concept of probabilistic- or random metric spaces, representing a natural extension of the metrical continuum into a more microscopic regime. It is our general goal to find a better adapted geometric environment for the description of microphysics. In this sense one may it also view as a dynamical randomisation of the causal-set framework developed by e.g. Sorkin et al. In doing this we incorporate, as a perhaps new aspect, various concepts from fuzzy set theory.

  11. Selling Random Energy

    E-Print Network [OSTI]

    Bitar, Eilyan Yamen

    2011-01-01

    continuous time model presented in Chapter 3 and model wind power production as a discrete time random process

  12. Refuting the odd number limitation of time-delayed feedback control

    E-Print Network [OSTI]

    B. Fiedler; V. Flunkert; M. Georgi; P. Hoevel; E. Schoell

    2007-02-12

    We refute an often invoked theorem which claims that a periodic orbit with an odd number of real Floquet multipliers greater than unity can never be stabilized by time-delayed feedback control in the form proposed by Pyragas. Using a generic normal form, we demonstrate that the unstable periodic orbit generated by a subcritical Hopf bifurcation, which has a single real unstable Floquet multiplier, can in fact be stabilized. We derive explicit analytical conditions for the control matrix in terms of the amplitude and the phase of the feedback control gain, and present a numerical example. Our results are of relevance for a wide range of systems in physics, chemistry, technology,and life sciences, where subcritical Hopf bifurcations occur.

  13. Reducing systematic errors in time-frequency resolved mode number analysis

    E-Print Network [OSTI]

    Horváth, L; Papp, G; Maraschek, M; Schuhbeck, K H; Pokol, G I

    2015-01-01

    The present paper describes the effect of magnetic pick-up coil transfer functions on mode number analysis in magnetically confined fusion plasmas. Magnetic probes mounted inside the vacuum chamber are widely used to characterize the mode structure of magnetohydrodynamic modes, as, due to their relative simplicity and compact nature, several coils can be distributed over the vessel. Phase differences between the transfer functions of different magnetic pick-up coils lead to systematic errors in time- and frequency resolved mode number analysis. This paper presents the first in-situ, end-to-end calibration of a magnetic pick-up coil system which was carried out by using an in-vessel driving coil on ASDEX Upgrade. The effect of the phase differences in the pick-up coil transfer functions is most significant in the 50-250 kHz frequency range, where the relative phase shift between the different probes can be up to 1 radian (~60{\\deg}). By applying a correction based on the transfer functions we found smaller res...

  14. Characterization of compounds by time-of-flight measurement utilizing random fast ions

    DOE Patents [OSTI]

    Conzemius, Robert J. (Ames, IA)

    1989-01-01

    An apparatus for characterizing the mass of sample and daughter particles, comprising a source for providing sample ions; a fragmentation region wherein a fraction of the sample ions may fragment to produce daughter ion particles; an electrostatic field region held at a voltage level sufficient to effect ion-neutral separation and ion-ion separation of fragments from the same sample ion and to separate ions of different kinetic energy; a detector system for measuring the relative arrival times of particles; and processing means operatively connected to the detector system to receive and store the relative arrival times and operable to compare the arrival times with times detected at the detector when the electrostatic field region is held at a different voltage level and to thereafter characterize the particles. Sample and daughter particles are characterized with respect to mass and other characteristics by detecting at a particle detector the relative time of arrival for fragments of a sample ion at two different electrostatic voltage levels. The two sets of particle arrival times are used in conjunction with the known altered voltage levels to mathematically characterize the sample and daughter fragments. In an alternative embodiment the present invention may be used as a detector for a conventional mass spectrometer. In this embodiment, conventional mass spectrometry analysis is enhanced due to further mass resolving of the detected ions.

  15. Characterization of compounds by time-of-flight measurement utilizing random fast ions

    DOE Patents [OSTI]

    Conzemius, R.J.

    1989-04-04

    An apparatus is described for characterizing the mass of sample and daughter particles, comprising a source for providing sample ions; a fragmentation region wherein a fraction of the sample ions may fragment to produce daughter ion particles; an electrostatic field region held at a voltage level sufficient to effect ion-neutral separation and ion-ion separation of fragments from the same sample ion and to separate ions of different kinetic energy; a detector system for measuring the relative arrival times of particles; and processing means operatively connected to the detector system to receive and store the relative arrival times and operable to compare the arrival times with times detected at the detector when the electrostatic field region is held at a different voltage level and to thereafter characterize the particles. Sample and daughter particles are characterized with respect to mass and other characteristics by detecting at a particle detector the relative time of arrival for fragments of a sample ion at two different electrostatic voltage levels. The two sets of particle arrival times are used in conjunction with the known altered voltage levels to mathematically characterize the sample and daughter fragments. In an alternative embodiment the present invention may be used as a detector for a conventional mass spectrometer. In this embodiment, conventional mass spectrometry analysis is enhanced due to further mass resolving of the detected ions. 8 figs.

  16. Effects of the spike timing-dependent plasticity on the synchronisation in a random Hodgkin-Huxley neuronal network

    E-Print Network [OSTI]

    R. R. Borges; F. S. Borges; A. M. Batista; E. L. Lameu; R. L. Viana; K. C. Iarosz; I. L. Caldas; M. A. F. Sanjuán

    2015-03-07

    In this paper, we study the effects of spike timing-dependent plasticity on synchronisation in a network of Hodgkin-Huxley neurons. Neuron plasticity is a flexible property of a neuron and its network to change temporarily or permanently their biochemical, physiological, and morphological characteristics, in order to adapt to the environment. Regarding the plasticity, we consider Hebbian rules, specifically for spike timing-dependent plasticity (STDP), and with regard to network, we consider that the connections are randomly distributed. We analyse the synchronisation and desynchronisation according to an input level and probability of connections. Moreover, we verify that the transition for synchronisation depends on the neuronal network architecture, and the external perturbation level.

  17. Space-Time Models based on Random Fields with Local Interactions

    E-Print Network [OSTI]

    Dionissios T. Hristopulos; Ivi C. Tsantili

    2015-03-06

    The analysis of space-time data from complex, real-life phenomena requires the use of flexible and physically motivated covariance functions. In most cases, it is not possible to explicitly solve the equations of motion for the fields or the respective covariance functions. In the statistical literature, covariance functions are often based on mathematical constructions. We propose deriving space-time covariance functions by solving "effective equations of motion", which can be used as statistical representations of systems with diffusive behavior. In particular, we propose using the linear response theory to formulate space-time covariance functions based on an equilibrium effective Hamiltonian. The effective space-time dynamics are then generated by a stochastic perturbation around the equilibrium point of the classical field Hamiltonian leading to an associated Langevin equation. We employ a Hamiltonian which extends the classical Gaussian field theory by including a curvature term and leads to a diffusive Langevin equation. Finally, we derive new forms of space-time covariance functions.

  18. Discrete-Time Pricing and Optimal Exercise of American Perpetual Warrants in the Geometric Random Walk Model

    SciTech Connect (OSTI)

    Vanderbei, Robert J., E-mail: rvdb@princeton.edu [Princeton University, Department of Operations Research and Financial Engineering (United States); P Latin-Small-Letter-Dotless-I nar, Mustafa C., E-mail: mustafap@bilkent.edu.tr [Bilkent University, Department of Industrial Engineering (Turkey); Bozkaya, Efe B. [Sabanc Latin-Small-Letter-Dotless-I University, Faculty of Administrative Sciences (Turkey)] [Sabanc Latin-Small-Letter-Dotless-I University, Faculty of Administrative Sciences (Turkey)

    2013-02-15

    An American option (or, warrant) is the right, but not the obligation, to purchase or sell an underlying equity at any time up to a predetermined expiration date for a predetermined amount. A perpetual American option differs from a plain American option in that it does not expire. In this study, we solve the optimal stopping problem of a perpetual American option (both call and put) in discrete time using linear programming duality. Under the assumption that the underlying stock price follows a discrete time and discrete state Markov process, namely a geometric random walk, we formulate the pricing problem as an infinite dimensional linear programming (LP) problem using the excessive-majorant property of the value function. This formulation allows us to solve complementary slackness conditions in closed-form, revealing an optimal stopping strategy which highlights the set of stock-prices where the option should be exercised. The analysis for the call option reveals that such a critical value exists only in some cases, depending on a combination of state-transition probabilities and the economic discount factor (i.e., the prevailing interest rate) whereas it ceases to be an issue for the put.

  19. Aging in reversible dynamics of disordered systems. II. Emergence of the arcsine law in the random hopping time dynamics of the REM

    E-Print Network [OSTI]

    Véronique Gayrard

    2010-08-23

    Applying the new tools developed in [G1], we investigate the arcsine aging regime of the random hopping time dynamics of the REM. Our results are optimal in several ways. They cover the full time-scale and temperature domain where this phenomenon occurs. On this domain the limiting clock process and associated time correlation function are explicitly constructed. Finally, all convergence statements w.r.t. the law of the random environment are obtained in the strongest sense possible, except perhaps on the very last scales before equilibrium.

  20. Analyses of the number of times married: U.S. women 1995-1996 

    E-Print Network [OSTI]

    Melick, Emily A

    2003-01-01

    indeed influence what many people in the United States today would consider the most personal of choices. This number can act as a simple measure of the chaos and stability associated in a woman's life, which influences her wealth, fertility experiences...

  1. Noise, Oscillators and Algebraic Randomness From Noise in Communication Systems to Number Theory. pp. 137-155 ; M. Planat, ed., Lecture Notes in Physics, Vol. 550, Springer (Berlin) 2000.

    E-Print Network [OSTI]

    Chapeau-Blondeau, François

    Noise, Oscillators and Algebraic Randomness ­ From Noise in Communication Systems to Number Theory resonance and the benefit of noise in nonlinear systems Fran¸cois Chapeau-Blondeau Laboratoire d effect wherein the noise turns out to be beneficial to the transmission or detection of an information

  2. Testing for Subcellular Randomness

    E-Print Network [OSTI]

    Babatunde O. Okunoye

    2008-01-29

    Statistical tests were conducted on 1,000 numbers generated from the genome of Bacteriophage T4, obtained from GenBank with accession number AF158101.The numbers passed the non-parametric, distribution-free tests.Deoxyribonucleic acid was discovered to be a random number generator, existent in nature.

  3. Method and allocation device for allocating pending requests for data packet transmission at a number of inputs to a number of outputs of a packet switching device in successive time slots

    DOE Patents [OSTI]

    Abel, Francois; Iliadis, Ilias; Minkenberg, Cyriel J. A.

    2009-02-03

    A method for allocating pending requests for data packet transmission at a number of inputs to a number of outputs of a switching system in successive time slots, including a matching method including the steps of providing a first request information in a first time slot indicating data packets at the inputs requesting transmission to the outputs of the switching system, performing a first step in the first time slot depending on the first request information to obtain a first matching information, providing a last request information in a last time slot successive to the first time slot, performing a last step in the last time slot depending on the last request information and depending on the first matching information to obtain a final matching information, and assigning the pending data packets at the number of inputs to the number of outputs based on the final matching information.

  4. A Possible Approach to Inclusion of Space and Time in Frame Fields of Quantum Representations of Real and Complex Numbers

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Benioff, Paul

    2009-01-01

    This work is based on the field of reference frames based on quantum representations of real and complex numbers described in other work. Here frame domains are expanded to include space and time lattices. Strings of qukits are described as hybrid systems as they are both mathematical and physical systems. As mathematical systems they represent numbers. As physical systems in each frame the strings have a discrete Schrodinger dynamics on the lattices. The frame field has an iterative structure such that the contents of a stagejframe have images in a stagej-1(parent) frame. A discussion of parent frame images includes themore »proposal that points of stagejframe lattices have images as hybrid systems in parent frames. The resulting association of energy with images of lattice point locations, as hybrid systems states, is discussed. Representations and images of other physical systems in the different frames are also described.« less

  5. 3 Continuous-time stochastic processes Definition 3.1. A continuous-time stochastic process is a collection of random variables (Xt, t R+)

    E-Print Network [OSTI]

    Lévêque, Olivier

    3 Continuous-time stochastic processes Definition 3.1. A continuous-time stochastic process to describe a continuous-time stochastic process, one generally needs a LARGE probability space ! Question. But having independent and stationary increments is a strong requirement for a continuous-time process

  6. Dismantling sparse random graphs

    E-Print Network [OSTI]

    Janson, Svante

    2007-01-01

    We consider the number of vertices that must be removed from a graph G in order that the remaining subgraph has no component with more than k vertices. Our principal observation is that, if G is a sparse random graph or a random regular graph on n vertices with n tending to infinity, then the number in question is essentially the same for all values of k such that k tends to infinity but k=o(n).

  7. Fast generation of sparse random kernel graphs

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Hagberg, Aric; Lemons, Nathan; Du, Wen -Bo

    2015-09-10

    The development of kernel-based inhomogeneous random graphs has provided models that are flexible enough to capture many observed characteristics of real networks, and that are also mathematically tractable. We specify a class of inhomogeneous random graph models, called random kernel graphs, that produces sparse graphs with tunable graph properties, and we develop an efficient generation algorithm to sample random instances from this model. As real-world networks are usually large, it is essential that the run-time of generation algorithms scales better than quadratically in the number of vertices n. We show that for many practical kernels our algorithm runs in timemore »at most ?(n(logn)²). As an example, we show how to generate samples of power-law degree distribution graphs with tunable assortativity.« less

  8. Randomly poled crystals as a source of photon pairs

    E-Print Network [OSTI]

    Jan Perina Jr; Jiri Svozilik

    2011-01-04

    Generation of photon pairs from randomly poled nonlinear crystals is investigated using analytically soluble model and numerical calculations. Randomly poled crystals are discovered as sources of entangled ultra broad-band signal and idler fields. Their photon-pair generation rates scale linearly with the number of domains. Entanglement times as short as several fs can be reached. Comparison with chirped periodically-poled structures is given and reveals close similarity.

  9. Course title and number: ACCK 450 Management Information Systems Term: Spring 2015 Meeting times: N/A Meeting location: Online

    E-Print Network [OSTI]

    Diestel, Geoff

    1 SYLLABUS Course title and number: ACCK 450 ­ Management Information Systems Term: Spring 2015 systems designed to meet the informational needs of the various business subsystems. The concepts stressed and detailed foundation in the principles of information systems through the most recent research, references

  10. Comp. by: MANIKANDAN R Stage: Proof Chapter No.: 110 Title Name: HbNS Date:19/3/12 Time:14:37:15 Page Number: 1

    E-Print Network [OSTI]

    Berridge, Kent

    are no longer 14 viewed solely from the angle of energy balance. Some refined ingredients, such 15 as sugarsNS Date:19/3/12 Time:14:37:15 Page Number: 2 16 addictive substances and their chronic overconsumption of energy and nutrients for growth, survival, and reproduction in 43 animal heterotrophs, including modern

  11. Nonlinear elastic polymers in random flow

    E-Print Network [OSTI]

    M. Martins Afonso; D. Vincenzi

    2005-08-09

    Polymer stretching in random smooth flows is investigated within the framework of the FENE dumbbell model. The advecting flow is Gaussian and short-correlated in time. The stationary probability density function of polymer extension is derived exactly. The characteristic time needed for the system to attain the stationary regime is computed as a function of the Weissenberg number and the maximum length of polymers. The transient relaxation to the stationary regime is predicted to be exceptionally slow in the proximity of the coil-stretch transition.

  12. Exploring the randomness of Directed Acyclic Networks

    E-Print Network [OSTI]

    Joaquín Goñi; Bernat Corominas-Murtra; Ricard V. Solé; Carlos Rodríguez-Caso

    2010-06-11

    The feed-forward relationship naturally observed in time-dependent processes and in a diverse number of real systems -such as some food-webs and electronic and neural wiring- can be described in terms of so-called directed acyclic graphs (DAGs). An important ingredient of the analysis of such networks is a proper comparison of their observed architecture against an ensemble of randomized graphs, thereby quantifying the {\\em randomness} of the real systems with respect to suitable null models. This approximation is particularly relevant when the finite size and/or large connectivity of real systems make inadequate a comparison with the predictions obtained from the so-called {\\em configuration model}. In this paper we analyze four methods of DAG randomization as defined by the desired combination of topological invariants (directed and undirected degree sequence and component distributions) aimed to be preserved. A highly ordered DAG, called \\textit{snake}-graph and a Erd\\:os-R\\'enyi DAG were used to validate the performance of the algorithms. Finally, three real case studies, namely, the \\textit{C. elegans} cell lineage network, a PhD student-advisor network and the Milgram's citation network were analyzed using each randomization method. Results show how the interpretation of degree-degree relations in DAGs respect to their randomized ensembles depend on the topological invariants imposed. In general, real DAGs provide disordered values, lower than the expected by chance when the directedness of the links is not preserved in the randomization process. Conversely, if the direction of the links is conserved throughout the randomization process, disorder indicators are close to the obtained from the null-model ensemble, although some deviations are observed.

  13. Random access wireless networks with controlled mobility

    E-Print Network [OSTI]

    Modiano, Eytan H.

    This paper considers wireless networks where messages arriving randomly (in time and space) are collected by a mobile receiver. The messages are transmitted to the mobile receiver according to a random access scheme and ...

  14. Random one-of-N selector

    DOE Patents [OSTI]

    Kronberg, James W. (353 Church Rd., Beech Island, SC 29841)

    1993-01-01

    An apparatus for selecting at random one item of N items on the average comprising counter and reset elements for counting repeatedly between zero and N, a number selected by the user, a circuit for activating and deactivating the counter, a comparator to determine if the counter stopped at a count of zero, an output to indicate an item has been selected when the count is zero or not selected if the count is not zero. Randomness is provided by having the counter cycle very often while varying the relatively longer duration between activation and deactivation of the count. The passive circuit components of the activating/deactivating circuit and those of the counter are selected for the sensitivity of their response to variations in temperature and other physical characteristics of the environment so that the response time of the circuitry varies. Additionally, the items themselves, which may be people, may vary in shape or the time they press a pushbutton, so that, for example, an ultrasonic beam broken by the item or person passing through it will add to the duration of the count and thus to the randomness of the selection.

  15. Random one-of-N selector

    DOE Patents [OSTI]

    Kronberg, J.W.

    1993-04-20

    An apparatus for selecting at random one item of N items on the average comprising counter and reset elements for counting repeatedly between zero and N, a number selected by the user, a circuit for activating and deactivating the counter, a comparator to determine if the counter stopped at a count of zero, an output to indicate an item has been selected when the count is zero or not selected if the count is not zero. Randomness is provided by having the counter cycle very often while varying the relatively longer duration between activation and deactivation of the count. The passive circuit components of the activating/deactivating circuit and those of the counter are selected for the sensitivity of their response to variations in temperature and other physical characteristics of the environment so that the response time of the circuitry varies. Additionally, the items themselves, which may be people, may vary in shape or the time they press a pushbutton, so that, for example, an ultrasonic beam broken by the item or person passing through it will add to the duration of the count and thus to the randomness of the selection.

  16. Long wave expansions for water waves over random topography

    E-Print Network [OSTI]

    Craig, Walter

    Long wave expansions for water waves over random topography Anne de Bouard1 , Walter Craig2 interacting with the random bottom. We show that the resulting influence of the random topography is expressed numbers: 76B15, 35Q53, 76M50, 60F17 Keywords :Water waves, random topography, long wave asymptotics #12

  17. Random Asynchronous Wakeup Protocol for Sensor Networks Vamsi Paruchuri, Shivakumar Basavaraju, Arjan Durresi, Rajgopal Kannan and S.S. Iyengar

    E-Print Network [OSTI]

    Durresi, Arjan

    density of nodes, only a small number of them need be active at any time to forward traffic for active, or to be active. Each node is awake for a randomly chosen fixed interval per time frame. High node density results in existence of several paths between two given nodes whose path length and de- lay characteristics are similar

  18. Random Walks and Electrical

    E-Print Network [OSTI]

    Jonathon Peterson

    2008-01-30

    Feb 4, 2008 ... Electrical Network Calculations in Random Walks in. Random ... Markov Chains. 2. Electrical Networks and Reversible Markov Chains. 3.

  19. Motivation Valued Outranking Digraphs Random Performance Tableaux Random Outranking Digraphs Conclusion Random Outranking Digraphs

    E-Print Network [OSTI]

    Bisdorff, Raymond

    Motivation Valued Outranking Digraphs Random Performance Tableaux Random Outranking Digraphs/CSC Leuven, January, 2009 Motivation Valued Outranking Digraphs Random Performance Tableaux Random Outranking Motivation Valued Outranking Digraphs Random Performance Tableaux Random Outranking Digraphs Conclusion

  20. Models of random graph hierarchies

    E-Print Network [OSTI]

    Paluch, Robert; Holyst, Janusz

    2015-01-01

    We introduce two models of inclusion hierarchies: Random Graph Hierarchy (RGH) and Limited Random Graph Hierarchy (LRGH). In both models a set of nodes at a given hierarchy level is connected randomly, as in the Erd\\H{o}s-R\\'{e}nyi random graph, with a fixed average degree equal to a system parameter $c$. Clusters of the resulting network are treated as nodes at the next hierarchy level and they are connected again at this level and so on, until the process cannot continue. In the RGH model we use all clusters, including those of size $1$, when building the next hierarchy level, while in the LRGH model clusters of size $1$ stop participating in further steps. We find that in both models the number of nodes at a given hierarchy level $h$ decreases approximately exponentially with $h$. The height of the hierarchy $H$, i.e. the number of all hierarchy levels, increases logarithmically with the system size $N$, i.e. with the number of nodes at the first level. The height $H$ decreases monotonically with the conne...

  1. VOLUME 87, NUMBER 7 P H Y S I C A L R E V I E W L E T T E R S 13 AUGUST 2001 Free Energy Self-Averaging in Protein-Sized Random Heteropolymers

    E-Print Network [OSTI]

    Chuang, Jeffrey

    tested, one of the most basic being self-averaging of the free energy. Self-averaging is a propertyVOLUME 87, NUMBER 7 P H Y S I C A L R E V I E W L E T T E R S 13 AUGUST 2001 Free Energy Self Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 2 Department

  2. Random rectangular Graphs

    E-Print Network [OSTI]

    Estrada, Ernesto

    2015-01-01

    A generalization of the random geometric graph (RGG) model is proposed by considering a set of points uniformly and independently distributed on a rectangle of unit area instead of on a unit square \\left[0,1\\right]^{2}. The topological properties, such as connectivity, average degree, average path length and clustering, of the random rectangular graphs (RRGs) generated by this model are then studied as a function of the rectangle sides lengths a and b=1/a, and the radius r used to connect the nodes. When a=1 we recover the RGG, and when a\\rightarrow\\infty the very elongated rectangle generated resembles a one-dimensional RGG. We provided computational and analytical evidence that the topological properties of the RRG differ significantly from those of the RGG. The connectivity of the RRG depends not only on the number of nodes as in the case of the RGG, but also on the side length of the rectangle. As the rectangle is more elongated the critical radius for connectivity increases following first a power-law an...

  3. IEEE TRANSACTIONS ON VERY LARGE SCALE INTEGRATION (VLSI) SYSTEMS, VOL. 21, NO. 4, APRIL 2013 761 The LUT-SR Family of Uniform Random

    E-Print Network [OSTI]

    Luk, Wayne

    developer man hours and CPU time. While it is possible to construct all possible generators ahead of time The LUT-SR Family of Uniform Random Number Generators for FPGA Architectures David B. Thomas, Member, IEEE generators (RNGs) are more resource-efficient than software-optimized RNGs because they can take advantage

  4. Course title and number: CISK 450 Management Information Systems Term: Spring 2015 Meeting times: MW 4:00 pm 5:15 pm Meeting location: FH 207

    E-Print Network [OSTI]

    Diestel, Geoff

    1 SYLLABUS Course title and number: CISK 450 ­ Management Information Systems Term: Spring 2015 information systems designed to meet the informational needs of the various business subsystems. The concepts students a solid and detailed foundation in the principles of information systems through the most recent

  5. Course title and number: CISK 450 Management Information Systems Term: Fall 2014 Meeting times: MW 4:00 pm 5:15 pm Meeting location: WH 308

    E-Print Network [OSTI]

    Diestel, Geoff

    1 SYLLABUS Course title and number: CISK 450 ­ Management Information Systems Term: Fall 2014 and Description: This course investigates management issues related to business information systems designed to meet the informational needs of the various business subsystems. The concepts stressed are systems

  6. WAKE FOREST BAPTIST MEDICAL CENTER OFFERS A NUMBER OF SUPPORTIVE SERVICES TO HELP FACULTY, STAFF, AND STUDENTS THROUGH TIMES OF STRESS AND CHANGE.

    E-Print Network [OSTI]

    Anderson, Paul R.

    WAKE FOREST BAPTIST MEDICAL CENTER OFFERS A NUMBER OF SUPPORTIVE SERVICES TO HELP FACULTY, STAFF to all employees. Counselors at EAP provide one-on-one sessions as well as group support, offering Greason offer supportive resources and may be contacted at studentwellness@wakehealth.edu or http

  7. Random Models Unit code: MATH20712

    E-Print Network [OSTI]

    Sidorov, Nikita

    MATH20712 Random Models Unit code: MATH20712 Credit Rating: 10 Unit level: Level 2 Teaching period, and renewal processes. Syllabus 1.Review of conditional probability, probability distributions, random. The probability of extinction. [6] 6.Renewal processes. The counting processes and occurrence time processes

  8. Secure sharing of random bits over the Internet

    E-Print Network [OSTI]

    Geraldo A. Barbosa

    2007-05-17

    Although one-time pad encrypted files can be sent through Internet channels, the need for renewing shared secret keys have made this method unpractical. This work presents a scheme to turn practical the fast sharing of random keys over arbitrary Internet channels. Starting with a shared secret key sequence of length K_0 the users end up with a secure new sequence K >> K_0. Using these sequences for posteriori message encryption the legitimate users have absolute security control without the need for third parties. Additionally, the security level does not depend on the unproven difficulty of factoring numbers in primes. In the proposed scheme a fast optical random source generates random bits and noise for key renewals. The transmitted signals are recorded signals that carries both the random binary signals to be exchanged and physical noise that cannot be eliminated by the attacker. These signals allow amplification over the Internet network without degrading security. The proposed system is also secure against a-posteriori known-plaintext attack on the key. Information-theoretic analysis is presented and bounds for secure operation are quantitatively determined.

  9. Nonlocal operators, parabolic-type equations, and ultrametric random walks

    SciTech Connect (OSTI)

    Chacón-Cortes, L. F., E-mail: fchaconc@math.cinvestav.edu.mx; Zúñiga-Galindo, W. A., E-mail: wazuniga@math.cinvestav.edu.mx [Centro de Investigacion y de Estudios Avanzados del I.P.N., Departamento de Matematicas, Av. Instituto Politecnico Nacional 2508, Col. San Pedro Zacatenco, Mexico D.F., C.P. 07360 (Mexico)

    2013-11-15

    In this article, we introduce a new type of nonlocal operators and study the Cauchy problem for certain parabolic-type pseudodifferential equations naturally associated to these operators. Some of these equations are the p-adic master equations of certain models of complex systems introduced by Avetisov, V. A. and Bikulov, A. Kh., “On the ultrametricity of the fluctuation dynamicmobility of protein molecules,” Proc. Steklov Inst. Math. 265(1), 75–81 (2009) [Tr. Mat. Inst. Steklova 265, 82–89 (2009) (Izbrannye Voprosy Matematicheskoy Fiziki i p-adicheskogo Analiza) (in Russian)]; Avetisov, V. A., Bikulov, A. Kh., and Zubarev, A. P., “First passage time distribution and the number of returns for ultrametric random walks,” J. Phys. A 42(8), 085003 (2009); Avetisov, V. A., Bikulov, A. Kh., and Osipov, V. A., “p-adic models of ultrametric diffusion in the conformational dynamics of macromolecules,” Proc. Steklov Inst. Math. 245(2), 48–57 (2004) [Tr. Mat. Inst. Steklova 245, 55–64 (2004) (Izbrannye Voprosy Matematicheskoy Fiziki i p-adicheskogo Analiza) (in Russian)]; Avetisov, V. A., Bikulov, A. Kh., and Osipov, V. A., “p-adic description of characteristic relaxation in complex systems,” J. Phys. A 36(15), 4239–4246 (2003); Avetisov, V. A., Bikulov, A. H., Kozyrev, S. V., and Osipov, V. A., “p-adic models of ultrametric diffusion constrained by hierarchical energy landscapes,” J. Phys. A 35(2), 177–189 (2002); Avetisov, V. A., Bikulov, A. Kh., and Kozyrev, S. V., “Description of logarithmic relaxation by a model of a hierarchical random walk,” Dokl. Akad. Nauk 368(2), 164–167 (1999) (in Russian). The fundamental solutions of these parabolic-type equations are transition functions of random walks on the n-dimensional vector space over the field of p-adic numbers. We study some properties of these random walks, including the first passage time.

  10. Nucleon transfer in heavy ion collisions with the time-dependent Hartree-Fock theory using a particle number projection technique

    E-Print Network [OSTI]

    Nucleon transfer in heavy ion collisions with the time-dependent Hartree-Fock theory using of Physics and Engineering, Australian National University, Canberra, Australian Capital Territory 0200-transfers are discussed. Binary collisions of many-body systems are of funda- mental interest to test dynamical approaches

  11. Selling Random Energy

    E-Print Network [OSTI]

    Bitar, Eilyan Yamen

    2011-01-01

    variability of wind and solar power production poses seriousof wind and solar power. They are essentially random – ais variability in wind an solar power production dealt with

  12. Random coincidence of $2\

    E-Print Network [OSTI]

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

    2013-01-17

    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\

  13. Change Number

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 OutreachProductswsicloudwsiclouddenDVA N C E D BGene Network ShapingDate: M-16-04-04 Federal FacilityChange Number

  14. Time Commitments Where Does Your Time Go

    E-Print Network [OSTI]

    Kunkle, Tom

    Time Commitments Where Does Your Time Go Everyone starts the week with the same number of hours. So, why does your time go so fast? Let's find out! Number of hours of sleep each night ____ x 7 preparation/clean-up time) ____ x 7 = ____ Travel time to and from campus ___ x __ = ____ Number of hours per

  15. 18.366 Random Walks and Diffusion, Spring 2003

    E-Print Network [OSTI]

    Bazant, Martin Z.

    Discrete and continuum modeling of diffusion processes in physics, chemistry, and economics. Topics include central limit theorems, continuous-time random walks, Levy flights, correlations, extreme events, mixing, ...

  16. 18.366 Random Walks and Diffusion, Spring 2005

    E-Print Network [OSTI]

    Bazant, Martin Z.

    Discrete and continuum modeling of diffusion processes in physics, chemistry, and economics. Topics include central limit theorems, continuous-time random walks, Levy flights, correlations, extreme events, mixing, ...

  17. True Random Number Generators Mario Stipcevic and etin Kaya Ko

    E-Print Network [OSTI]

    , prepaid cards, wireless keys, general cybersecurity, distributed power grid security (SCADA), etc. Without

  18. Version: November 25, 1997 A Random Number Generator

    E-Print Network [OSTI]

    L'Ecuyer, Pierre

    'ECUYER Universit'e de Montr'eal Terry H. ANDRES Atomic Energy of Canada Limited ABSTRACT: A portable package'epartement d'Informatique et de Recherche Op'erationnelle (IRO), Universit'e de Montr'eal, C.P. 6128, Succ. Centre­Ville, Montr'eal, H3C 3J7, Canada; e­mail: lecuyer@iro.umontreal.ca www: http

  19. Good Practice in (Pseudo) Random Number Generation for Bioinformatics Applications

    E-Print Network [OSTI]

    Jones, David T.

    () and drand48() #12;Matlab's rand Mathematica's SWB generator ran0() and ran1() in the original Numerical

  20. Anosov C-systems and random number generators

    E-Print Network [OSTI]

    George Savvidy

    2015-09-04

    We are developing further our earlier suggestion to use hyperbolic Anosov C-systems for the Monte-Carlo simulations in high energy particle physics. The hyperbolic dynamical systems have homogeneous instability of all trajectories and as such they have mixing of all orders, countable Lebesgue spectrum and positive Kolmogorov entropy. These extraordinary ergodic properties follow from the C-condition introduced by Anosov. The C-condition defines a rich class of dynamical systems which span an open set in the space of all dynamical systems. The important property of C-systems is that they have a countable set of everywhere dense periodic trajectories and that their density exponentially increases with entropy. Of special interest are C-systems that are defined on a high dimensional torus. The C-systems on a torus are perfect candidates to be used for Monte-Carlo simulations. Recently an efficient algorithm was found, which allows very fast generation of long trajectories of the C-systems. These trajectories have high quality statistical properties and we are suggesting to use them for the QCD lattice simulations and at high energy particle physics.

  1. Statistics and Technology 1 Generating Random Numbers 3

    E-Print Network [OSTI]

    the frequencies (counts) on the chart, right click one of the bars and click "Add Data Labels." · Pie Charts under "Pie." 4. The pie chart will appear, but it may need some formatting changes to be readable. You it readable. 5. To show the frequencies (counts) on the chart, right click one of the pie pieces and click

  2. Sample-dependent first-passage time distribution in a disordered medium

    E-Print Network [OSTI]

    Liang Luo; Lei-Han Tang

    2015-09-26

    Above two dimensions, diffusion of a particle in a medium with quenched random traps is believed to be well-described by the annealed continuous time random walk (CTRW). We propose an approximate expression for the first-passage-time (FPT) distribution in a given sample that enables detailed comparison of the two problems. For a system of finite size, the number and spatial arrangement of deep traps yield significant sample-to-sample variations in the FPT statistics. Numerical simulations of a quenched trap model with power-law sojourn times confirm the existence of two characteristic time scales and a non-self-averaging FPT distribution, as predicted by theory.

  3. From the Academy Random matrices and quantum chaos

    E-Print Network [OSTI]

    Marklof, Jens

    From the Academy Random matrices and quantum chaos Thomas Kriecherbauer*, Jens Marklof appearances of random matrices, namely in the theory of quantum chaos and in the theory of prime numbers, in fact, are not only used to describe statistical properties of physical systems (e.g., in quantum chaos

  4. Byzantine Modification Detection in Multicast Networks with Random Network Coding

    E-Print Network [OSTI]

    Médard, Muriel

    network coding. Each exogenous source packet is augmented with a flexible number of hash symbols of the random network code, and can have the same (or greater) transmission capacity compared to the sourceByzantine Modification Detection in Multicast Networks with Random Network Coding Tracey Ho, Ben

  5. EXPONENTIAL STABILITY OF THE QUASIGEOSTROPHIC EQUATION UNDER RANDOM PERTURBATIONS

    E-Print Network [OSTI]

    small scale mo- tions. For this reason we believe that, under the random media or random wind forcing model at asymp- totically high rotation rate or at small Rossby number. It is derived as an ap- proximation of the rotating shallow water equations by a conventional asymptotic expansion for small Rossby

  6. Selling Random Energy

    E-Print Network [OSTI]

    Bitar, Eilyan Yamen

    2011-01-01

    Selling Random Energy in a Two-Settlement System 3.1Wind Energy Aggregation and Profit Sharing 4.1 IntroductionPower Model . . . . . . . . . . . . . 5.3.2 Energy Storage

  7. Directed random testing

    E-Print Network [OSTI]

    Pacheco, Carlos, Ph.D. Massachusetts Institute of Technology

    2009-01-01

    Random testing can quickly generate many tests, is easy to implement, scales to large software applications, and reveals software errors. But it tends to generate many tests that are illegal or that exercise the same parts ...

  8. Random array grid collimator

    DOE Patents [OSTI]

    Fenimore, E.E.

    1980-08-22

    A hexagonally shaped quasi-random no-two-holes touching grid collimator. The quasi-random array grid collimator eliminates contamination from small angle off-axis rays by using a no-two-holes-touching pattern which simultaneously provides for a self-supporting array increasng throughput by elimination of a substrate. The presentation invention also provides maximum throughput using hexagonally shaped holes in a hexagonal lattice pattern for diffraction limited applications. Mosaicking is also disclosed for reducing fabrication effort.

  9. Electrokinetic transport in microchannels with random roughness

    SciTech Connect (OSTI)

    Wang, Moran [Los Alamos National Laboratory; Kang, Qinjun [Los Alamos National Laboratory

    2008-01-01

    We present a numerical framework to model the electrokinetic transport in microchannels with random roughness. The three-dimensional microstructure of the rough channel is generated by a random generation-growth method with three statistical parameters to control the number density, the total volume fraction, and the anisotropy characteristics of roughness elements. The governing equations for the electrokinetic transport are solved by a high-efficiency lattice Poisson?Boltzmann method in complex geometries. The effects from the geometric characteristics of roughness on the electrokinetic transport in microchannels are therefore modeled and analyzed. For a given total roughness volume fraction, a higher number density leads to a lower fluctuation because of the random factors. The electroosmotic flow rate increases with the roughness number density nearly logarithmically for a given volume fraction of roughness but decreases with the volume fraction for a given roughness number density. When both the volume fraction and the number density of roughness are given, the electroosmotic flow rate is enhanced by the increase of the characteristic length along the external electric field direction but is reduced by that in the direction across the channel. For a given microstructure of the rough microchannel, the electroosmotic flow rate decreases with the Debye length. It is found that the shape resistance of roughness is responsible for the flow rate reduction in the rough channel compared to the smooth channel even for very thin double layers, and hence plays an important role in microchannel electroosmotic flows.

  10. A discrete fractional random transform

    E-Print Network [OSTI]

    Zhengjun Liu; Haifa Zhao; Shutian Liu

    2006-05-20

    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.

  11. Time Consistent Risk Measure Under Stopping Time Framework ...

    E-Print Network [OSTI]

    2015-02-13

    to the stochastic volatility of security markets and constantly change of economic and financial information, the earliest target reaching time is random, it then ...

  12. Report number codes

    SciTech Connect (OSTI)

    Nelson, R.N.

    1985-05-01

    This publication lists all report number codes processed by the Office of Scientific and Technical Information. The report codes are substantially based on the American National Standards Institute, Standard Technical Report Number (STRN)-Format and Creation Z39.23-1983. The Standard Technical Report Number (STRN) provides one of the primary methods of identifying a specific technical report. The STRN consists of two parts: The report code and the sequential number. The report code identifies the issuing organization, a specific program, or a type of document. The sequential number, which is assigned in sequence by each report issuing entity, is not included in this publication. Part I of this compilation is alphabetized by report codes followed by issuing installations. Part II lists the issuing organization followed by the assigned report code(s). In both Parts I and II, the names of issuing organizations appear for the most part in the form used at the time the reports were issued. However, for some of the more prolific installations which have had name changes, all entries have been merged under the current name.

  13. Diffusion in randomly perturbed dissipative dynamics

    E-Print Network [OSTI]

    Christian S. Rodrigues; Aleksei V. Chechkin; Alessandro P. S. de Moura; Celso Grebogi; Rainer Klages

    2014-11-13

    Dynamical systems having many coexisting attractors present interesting properties from both fundamental theoretical and modelling points of view. When such dynamics is under bounded random perturbations, the basins of attraction are no longer invariant and there is the possibility of transport among them. Here we introduce a basic theoretical setting which enables us to study this hopping process from the perspective of anomalous transport using the concept of a random dynamical system with holes. We apply it to a simple model by investigating the role of hyperbolicity for the transport among basins. We show numerically that our system exhibits non-Gaussian position distributions, power-law escape times, and subdiffusion. Our simulation results are reproduced consistently from stochastic Continuous Time Random Walk theory.

  14. Real-Time Deferrable Load Control: Handling the Uncertainties of Renewable Generation

    E-Print Network [OSTI]

    Low, Steven H.

    Real-Time Deferrable Load Control: Handling the Uncertainties of Renewable Generation Lingwen Gan to handle the un- certainties of renewable generation. It is expected that a large number of deferrable for the random fluctuations in renewable generation. Work on deferrable load control falls into two categories

  15. New Paradigms for Digital Generation and Post-Processing of Random Data

    E-Print Network [OSTI]

    International Association for Cryptologic Research (IACR)

    . The generated random binary sequences inherently have a high speed and a very high and robust entropy rate and memories in such devices. The output of a random number generator (RNG) is typically a binary sequenceNew Paradigms for Digital Generation and Post-Processing of Random Data #3; Jovan Dj. Goli#19;c

  16. Distributed Algorithms with Dynamical Random Transitions

    E-Print Network [OSTI]

    Henri Poincaré -Nancy-Université, Université

    of the storage allocation system is taken as a function of time to be a #12;nite-state Markov chain resources where allocation and deal- location requests are dynamic random variables. This stochastic model, 16, 19]. The technique is applicable to other stochastically modelled resource allocation protocoles

  17. Recombination of polynucleotide sequences using random or defined primers

    DOE Patents [OSTI]

    Arnold, Frances H. (Pasadena, CA); Shao, Zhixin (Pasadena, CA); Affholter, Joseph A. (Midland, MI); Zhao, Huimin (Pasadena, CA); Giver, Lorraine J. (Pasadena, CA)

    2001-01-01

    A method for in vitro mutagenesis and recombination of polynucleotide sequences based on polymerase-catalyzed extension of primer oligonucleotides is disclosed. The method involves priming template polynucleotide(s) with random-sequences or defined-sequence primers to generate a pool of short DNA fragments with a low level of point mutations. The DNA fragments are subjected to denaturization followed by annealing and further enzyme-catalyzed DNA polymerization. This procedure is repeated a sufficient number of times to produce full-length genes which comprise mutants of the original template polynucleotides. These genes can be further amplified by the polymerase chain reaction and cloned into a vector for expression of the encoded proteins.

  18. Recombination of polynucleotide sequences using random or defined primers

    DOE Patents [OSTI]

    Arnold, Frances H. (Pasadena, CA); Shao, Zhixin (Pasadena, CA); Affholter, Joseph A. (Midland, MI); Zhao, Huimin H (San Diego, CA); Giver, Lorraine J. (Sunnyvale, CA)

    2000-01-01

    A method for in vitro mutagenesis and recombination of polynucleotide sequences based on polymerase-catalyzed extension of primer oligonucleotides is disclosed. The method involves priming template polynucleotide(s) with random-sequences or defined-sequence primers to generate a pool of short DNA fragments with a low level of point mutations. The DNA fragments are subjected to denaturization followed by annealing and further enzyme-catalyzed DNA polymerization. This procedure is repeated a sufficient number of times to produce full-length genes which comprise mutants of the original template polynucleotides. These genes can be further amplified by the polymerase chain reaction and cloned into a vector for expression of the encoded proteins.

  19. Randomization vs. Nondeterminisma What are the differences between randomized algorithms

    E-Print Network [OSTI]

    Lyuu, Yuh-Dauh

    Inequalitya Lemma 61 Let x be a random variable taking nonnegative integer values. Then for any k > 0, prob[ x

  20. Free Energy Fluctuations for Directed Polymers in Random Media in 1?+?1 Dimension

    E-Print Network [OSTI]

    Borodin, Alexei

    We consider two models for directed polymers in space-time independent random media (the O'Connell-Yor semidiscrete directed polymer and the continuum directed random polymer) at positive temperature and prove their KPZ ...

  1. Randomized Algorithms with Splitting: Why the Classic Randomized Algorithms

    E-Print Network [OSTI]

    Del Moral , Pierre

    Randomized Algorithms with Splitting: Why the Classic Randomized Algorithms do not Work and how Abstract We show that the original classic randomized algorithms for approximate counting in NP simultaneously multiple Markov chains. We present several algorithms of the combined version, which we simple

  2. RandFile package for Mathematica for accessing file-based sources of randomness

    E-Print Network [OSTI]

    J. A. Miszczak; M. Wahl

    2015-03-15

    We present a package for Mathematica computer algebra system which allows the exploitation of local files as sources of random data. We provide the description of the package and illustrate its usage by showing some examples. We also compare the provided functionality with alternative sources of randomness, namely a built-in pseudo-random generator and the package for accessing hardware true random number generators.

  3. Aging and quenched localization for one-dimensional random walks in random environment in the sub-ballistic regime

    E-Print Network [OSTI]

    Nathanaël Enriquez; Christophe Sabot; Olivier Zindy

    2009-04-09

    We consider transient one-dimensional random walks in random environment with zero asymptotic speed. An aging phenomenon involving the generalized Arcsine law is proved using the localization of the walk at the foot of "valleys" of height $\\log t$. In the quenched setting, we also sharply estimate the distribution of the walk at time $t$.

  4. Emergence of typical entanglement in two-party random processes

    E-Print Network [OSTI]

    O. C. O. Dahlsten; R. Oliveira; M. B. Plenio

    2007-01-17

    We investigate the entanglement within a system undergoing a random, local process. We find that there is initially a phase of very fast generation and spread of entanglement. At the end of this phase the entanglement is typically maximal. In previous work we proved that the maximal entanglement is reached to a fixed arbitrary accuracy within $O(N^3)$ steps, where $N$ is the total number of qubits. Here we provide a detailed and more pedagogical proof. We demonstrate that one can use the so-called stabilizer gates to simulate this process efficiently on a classical computer. Furthermore, we discuss three ways of identifying the transition from the phase of rapid spread of entanglement to the stationary phase: (i) the time when saturation of the maximal entanglement is achieved, (ii) the cut-off moment, when the entanglement probability distribution is practically stationary, and (iii) the moment block entanglement scales exhibits volume scaling. We furthermore investigate the mixed state and multipartite setting. Numerically we find that classical and quantum correlations appear to behave similarly and that there is a well-behaved phase-space flow of entanglement properties towards an equilibrium, We describe how the emergence of typical entanglement can be used to create a much simpler tripartite entanglement description. The results form a bridge between certain abstract results concerning typical (also known as generic) entanglement relative to an unbiased distribution on pure states and the more physical picture of distributions emerging from random local interactions.

  5. Random intersection graphs and their applications in security, wireless communication, and social networks

    E-Print Network [OSTI]

    Zhao, Jun; Gligor, Virgil

    2015-01-01

    Random intersection graphs have received much interest and been used in diverse applications. They are naturally induced in modeling secure sensor networks under random key predistribution schemes, as well as in modeling the topologies of social networks including common-interest networks, collaboration networks, and actor networks. Simply put, a random intersection graph is constructed by assigning each node a set of items in some random manner and then putting an edge between any two nodes that share a certain number of items. Broadly speaking, our work is about analyzing random intersection graphs, and models generated by composing it with other random graph models including random geometric graphs and Erd\\H{o}s-R\\'enyi graphs. These compositional models are introduced to capture the characteristics of various complex natural or man-made networks more accurately than the existing models in the literature. For random intersection graphs and their compositions with other random graphs, we study properties su...

  6. Combinatorial theory of the semiclassical evaluation of transport moments. I. Equivalence with the random matrix approach

    SciTech Connect (OSTI)

    Berkolaiko, G.; Kuipers, J.

    2013-11-15

    To study electronic transport through chaotic quantum dots, there are two main theoretical approaches. One involves substituting the quantum system with a random scattering matrix and performing appropriate ensemble averaging. The other treats the transport in the semiclassical approximation and studies correlations among sets of classical trajectories. There are established evaluation procedures within the semiclassical evaluation that, for several linear and nonlinear transport moments to which they were applied, have always resulted in the agreement with random matrix predictions. We prove that this agreement is universal: any semiclassical evaluation within the accepted procedures is equivalent to the evaluation within random matrix theory. The equivalence is shown by developing a combinatorial interpretation of the trajectory sets as ribbon graphs (maps) with certain properties and exhibiting systematic cancellations among their contributions. Remaining trajectory sets can be identified with primitive (palindromic) factorisations whose number gives the coefficients in the corresponding expansion of the moments of random matrices. The equivalence is proved for systems with and without time reversal symmetry.

  7. Random Selection for Drug Screening

    SciTech Connect (OSTI)

    Center for Human Reliability Studies

    2007-05-01

    Simple random sampling is generally the starting point for a random sampling process. This sampling technique ensures that each individual within a group (population) has an equal chance of being selected. There are a variety of ways to implement random sampling in a practical situation.

  8. Autosomal random asynchronous replication is analogous to X-chromosome inactivation

    E-Print Network [OSTI]

    Ensminger, Alexander Wilson

    2006-01-01

    A number of mammalian genes are expressed from only one of two alleles in either an imprinted or random manner. Those belonging to the random class include X-linked genes subject to X inactivation, as well as a number of ...

  9. Clauser-Horne Bell test with imperfect random inputs

    E-Print Network [OSTI]

    Xiao Yuan; Qi Zhao; Xiongfeng Ma

    2015-05-16

    Bell test is one of the most important tools in quantum information science. On the one hand, it enables fundamental test for the physics laws of nature, and on the other hand, it can be also applied in varieties of device independent tasks such as quantum key distribution and random number generation. In practice, loopholes existing in experimental demonstrations of Bell tests may affect the validity of the conclusions. In this work, we focus on the randomness (freewill) loophole and investigate the randomness requirement in a well-known Bell test, the Clauser-Horne test, under various conditions. With partially random inputs, we explicitly bound the Bell value for all local hidden variable models by optimizing the classical strategy. Our result thus puts input randomness requirement on the Clauser-Horne test under varieties of practical scenarios. The employed analysis technique can be generalized to other Bell's inequalities.

  10. Component evolution in general random intersection graphs

    SciTech Connect (OSTI)

    Bradonjic, Milan [Los Alamos National Laboratory; Hagberg, Aric [Los Alamos National Laboratory; Hengartner, Nick [Los Alamos National Laboratory; Percus, Allon G [CLAREMONT GRADUATE UNIV.

    2010-01-01

    We analyze component evolution in general random intersection graphs (RIGs) and give conditions on existence and uniqueness of the giant component. Our techniques generalize the existing methods for analysis on component evolution in RIGs. That is, we analyze survival and extinction properties of a dependent, inhomogeneous Galton-Watson branching process on general RIGs. Our analysis relies on bounding the branching processes and inherits the fundamental concepts from the study on component evolution in Erdos-Renyi graphs. The main challenge becomes from the underlying structure of RIGs, when the number of offsprings follows a binomial distribution with a different number of nodes and different rate at each step during the evolution. RIGs can be interpreted as a model for large randomly formed non-metric data sets. Besides the mathematical analysis on component evolution, which we provide in this work, we perceive RIGs as an important random structure which has already found applications in social networks, epidemic networks, blog readership, or wireless sensor networks.

  11. Small particle limits in a regularized Laplacian random growth model

    E-Print Network [OSTI]

    Fredrik Johansson Viklund; Alan Sola; Amanda Turner

    2013-10-23

    We study a regularized version of Hastings-Levitov planar random growth that models clusters formed by the aggregation of diffusing particles. In this model, the growing clusters are defined in terms of iterated slit maps whose capacities are given by c_n=c|\\Phi_{n-1}'(e^{\\sigma+i\\theta_n})|^{-\\alpha}, \\alpha \\geq 0, where c>0 is the capacity of the first particle, {\\Phi_n}_n are the composed conformal maps defining the clusters of the evolution, {\\theta_n}_n are independent uniform angles determining the positions at which particles are attached, and \\sigma>0 is a regularization parameter which we take to depend on c. We prove that under an appropriate rescaling of time, in the limit as c converges to 0, the clusters converge to growing disks with deterministic capacities, provided that \\sigma does not converge to 0 too fast. We then establish scaling limits for the harmonic measure flow, showing that by letting \\alpha tend to 0 at different rates it converges to either the Brownian web on the circle, a stopped version of the Brownian web on the circle, or the identity map. As the harmonic measure flow is closely related to the internal branching structure within the cluster, the above three cases intuitively correspond to the number of infinite branches in the model being either 1, a random number whose distribution we obtain, or unbounded, in the limit as c converges to 0. We also present several findings based on simulations of the model with parameter choices not covered by our rigorous analysis.

  12. Accelerated Randomized Benchmarking

    E-Print Network [OSTI]

    Christopher Granade; Christopher Ferrie; D. G. Cory

    2014-09-24

    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.

  13. Compendium of Experimental Cetane Numbers

    SciTech Connect (OSTI)

    Yanowitz, J.; Ratcliff, M. A.; McCormick, R. L.; Taylor, J. D.; Murphy, M. J.

    2014-08-01

    This report is an updated version of the 2004 Compendium of Experimental Cetane Number Data and presents a compilation of measured cetane numbers for pure chemical compounds. It includes all available single compound cetane number data found in the scientific literature up until March 2014 as well as a number of unpublished values, most measured over the past decade at the National Renewable Energy Laboratory. This Compendium contains cetane values for 389 pure compounds, including 189 hydrocarbons and 201 oxygenates. More than 250 individual measurements are new to this version of the Compendium. For many compounds, numerous measurements are included, often collected by different researchers using different methods. Cetane number is a relative ranking of a fuel's autoignition characteristics for use in compression ignition engines; it is based on the amount of time between fuel injection and ignition, also known as ignition delay. The cetane number is typically measured either in a single-cylinder engine or a constant volume combustion chamber. Values in the previous Compendium derived from octane numbers have been removed, and replaced with a brief analysis of the correlation between cetane numbers and octane numbers. The discussion on the accuracy and precision of the most commonly used methods for measuring cetane has been expanded and the data has been annotated extensively to provide additional information that will help the reader judge the relative reliability of individual results.

  14. On Ramsey Numbers

    E-Print Network [OSTI]

    Dhananjay P. Mehendale

    2006-05-24

    In this paper we define new numbers called the Neo-Ramsay numbers. We show that these numbers are in fact equal to the Ramsay numbers. Neo-Ramsey numbers are easy to compute and for finding them it is not necessary to check all possible graphs but enough to check only special kind of graphs having a well-defined adjacency pattern.

  15. Organization of growing random networks

    SciTech Connect (OSTI)

    Krapivsky, P. L.; Redner, S.

    2001-06-01

    The organizational development of growing random networks is investigated. These growing networks are built by adding nodes successively, and linking each to an earlier node of degree k with an attachment probability A{sub k}. When A{sub k} grows more slowly than linearly with k, the number of nodes with k links, N{sub k}(t), decays faster than a power law in k, while for A{sub k} growing faster than linearly in k, a single node emerges which connects to nearly all other nodes. When A{sub k} is asymptotically linear, N{sub k}(t){similar_to}tk{sup {minus}{nu}}, with {nu} dependent on details of the attachment probability, but in the range 2{lt}{nu}{lt}{infinity}. The combined age and degree distribution of nodes shows that old nodes typically have a large degree. There is also a significant correlation in the degrees of neighboring nodes, so that nodes of similar degree are more likely to be connected. The size distributions of the in and out components of the network with respect to a given node{emdash}namely, its {open_quotes}descendants{close_quotes} and {open_quotes}ancestors{close_quotes}{emdash}are also determined. The in component exhibits a robust s{sup {minus}2} power-law tail, where s is the component size. The out component has a typical size of order lnt, and it provides basic insights into the genealogy of the network.

  16. Random Operator Compressions

    E-Print Network [OSTI]

    Stephen Ng; Meg Walters

    2014-09-19

    Let $A$ be a Hermitian operator of order $n$. We show that for $k\\leq n$ sufficiently large, the eigenvalues of a compression of $A$ to a $k$-dimensional subspace are almost the same for all subspaces. We prove this result using the methods introduced in a paper by Chatterjee and Ledoux on eigenvalues of principle submatrices. We show that by choosing an appropriate Markov chain, the methods of Chatterjee and Ledoux can be applied to give a more general result on operator compressions. As an additional application of this method, we prove concentration of measure of the length of the longest increasing subsequence of a random walk distributed under the invariant measure for the asymmetric exclusion process.

  17. 1 -Routing Number 2 -Account Number

    E-Print Network [OSTI]

    Chen, Yiling

    you will need: · Your Harvard University Id Number (HUID) · Your HUID pin number · Your Checking/Savings on the right side of the screen under Payroll and Compensation. #12;*Please, in an effort to save paper and if you do not wish to receive a paper copy of the check. Click the small box above the SAVE button. CLICK

  18. Stretched Polymers in Random Environment

    E-Print Network [OSTI]

    Dmitry Ioffe; Yvan Velenik

    2011-03-01

    We survey recent results and open questions on the ballistic phase of stretched polymers in both annealed and quenched random environments.

  19. Hyperdiffusion of quantum waves in random photonic lattices

    E-Print Network [OSTI]

    Alexander Iomin

    2015-08-24

    A quantum-mechanical analysis of hyper-fast (faster than ballistic) diffusion of a quantum wave packet in random optical lattices is presented. The main motivation of the presented analysis is experimental demonstrations of hyper-diffusive spreading of a wave packet in random photonic lattices [L. Levi \\textit{et al.}, Nature Phys. \\textbf{8}, 912 (2012)]. A rigorous quantum-mechanical calculation of the mean probability amplitude is suggested, and it is shown that the power law spreading of the mean squared displacement (MSD) is $\\sim t^{\\alpha}$, where $2potential $V(x,t)$, which describes random inhomogeneities of the medium. In particular, when the random potential is $\\delta$ correlated in time, the quantum wave packet spreads according Richardson turbulent diffusion with the MSD $\\sim t^3$. Hyper-diffusion with $\\alpha=12/5$ is also obtained for arbitrary correlation properties of the random potential.

  20. Student ID (R) Number ________________________ Semester/Year______ ________________________

    E-Print Network [OSTI]

    Rock, Chris

    Student ID (R) Number ________________________ Semester/Year______ ________________________ THIRD: ______________________________________________________ CHECK ALL THAT APPLY: _____First-time Third Party Student _____TTU Campus Student _____Non sponsor and the Third Party Sponsor Agreement prior to the due date to ensure timely posting of third

  1. Related Randomness Attacks for Public Key Encryption Kenneth G. Paterson, Jacob C. N. Schuldt, Dale L. Sibborn

    E-Print Network [OSTI]

    International Association for Cryptologic Research (IACR)

    that randomness failures of var- ious kinds are endemic in deployed cryptographic systems. In the face of this ­ cryptographic schemes against such failures. This paper considers the practically-motivated situation where are heavy consumers of randomness. Unfortunately, random number generators (RNGs) used to provide

  2. Experimental quantum randomness generation invulnerable to the detection loophole

    E-Print Network [OSTI]

    Gustavo Cañas; Jaime Cariñe; Esteban S. Gómez; Johanna F. Barra; Adán Cabello; Guilherme B. Xavier; Gustavo Lima; Marcin Paw?owski

    2014-10-28

    Random numbers are essential for multiple applications, including cryptography, financial security, digital rights management and scientific simulations. However, producing random numbers from a finite state machine, such as a classical computer, is impossible. One option is to use conventional quantum random number generators (QRNGs) based on the intrinsic uncertainty of quantum measurement outcomes. The problem in this case is that private randomness relies on assumptions on the internal functioning of the measurement devices. "Device-independent" QRNGs not relying on devices inner workings assumptions can be built but are impractical. They require a detection efficiency that, so far, has only be achieved with trapped ions and with photons detected with transition-edge superconducting sensors. Here we introduce a novel protocol for quantum private randomness generation that makes no assumption on the functioning of the devices and works even with very low detection efficiency. We implement the protocol using weak coherent states and standard single-photon detectors. Our results pave the way towards a second generation of more secure practical QRNGs.

  3. Number of peer-reviewed publications

    E-Print Network [OSTI]

    ·Number of peer- reviewed publications produced per year ·Data accurate as of 02 April 2012 · Number of publications produced per institution (top 10) ·Collaborations counted multiple times · Non-cumulative number of citations received by OER publications per year ·Data accurate as of 02 April 2012 · The work

  4. Supply Chain Supernetworks Random Demands

    E-Print Network [OSTI]

    Nagurney, Anna

    Supply Chain Supernetworks with Random Demands June Dong and Ding Zhang Department of Marketing of three tiers of decision-makers: the manufacturers, the distributors, and the retailers, with the demands equilibrium model with electronic commerce and with random demands for which modeling, qualitative analysis

  5. Random Curves by Conformal Welding

    E-Print Network [OSTI]

    K. Astala; P. Jones; A. Kupiainen; E. Saksman

    2009-12-17

    We construct a conformally invariant random family of closed curves in the plane by welding of random homeomorphisms of the unit circle given in terms of the exponential of Gaussian Free Field. We conjecture that our curves are locally related to SLE$(\\kappa)$ for $\\kappa<4$.

  6. Random Curves by Conformal Welding

    E-Print Network [OSTI]

    Astala, K; Kupiainen, A; Saksman, E

    2009-01-01

    We construct a conformally invariant random family of closed curves in the plane by welding of random homeomorphisms of the unit circle given in terms of the exponential of Gaussian Free Field. We conjecture that our curves are locally related to SLE$(\\kappa)$ for $\\kappa<4$.

  7. A complete Randomized Benchmarking Protocol accounting for Leakage Errors

    E-Print Network [OSTI]

    T. Chasseur; F. K. Wilhelm

    2015-07-09

    Randomized Benchmarking allows to efficiently and scalably characterize the average error of an unitary 2-design such as the Clifford group $\\mathcal{C}$ on a physical candidate for quantum computation, as long as there are no non-computational leakage levels in the system. We investigate the effect of leakage errors on Randomized Benchmarking induced from an additional level per physical qubit and provide a modified protocol that allows to derive reliable estimates for the error per gate in their presence. We assess the variance of the sequence fidelity corresponding to the number of random sequences needed for valid fidelity estimation. Our protocol allows for gate dependent error channels without being restricted to perturbations. We show that our protocol is compatible with Interleaved Randomized Benchmarking and expand to benchmarking of arbitrary gates. This setting is relevant for superconducting transmon qubits, among other systems.

  8. Certified counting of roots of random univariate polynomials

    E-Print Network [OSTI]

    Joseph Cleveland; Jeffrey Dzugan; Jonathan D. Hauenstein; Ian Haywood; Dhagash Mehta; Anthony Morse; Leonardo Robol; Taylor Schlenk

    2014-12-04

    A challenging problem in computational mathematics is to compute roots of a high-degree univariate random polynomial. We combine an efficient multiprecision implementation for solving high-degree random polynomials with two certification methods, namely Smale's $\\alpha$-theory and one based on Gerschgorin's theorem, for showing that a given numerical approximation is in the quadratic convergence region of Newton's method of some exact solution. With this combination, we can certifiably count the number of real roots of random polynomials. We quantify the difference between the two certification procedures and list the salient features of both of them. After benchmarking on random polynomials where the coefficients are drawn from the Gaussian distribution, we obtain novel experimental results for the Cauchy distribution case.

  9. Multilayer parking with screening on a random tree

    E-Print Network [OSTI]

    S. R. Fleurke; C. Kuelske

    2009-11-05

    In this paper we present a multilayer particle deposition model on a random tree. We derive the time dependent densities of the first and second layer analytically and show that in all trees the limiting density of the first layer exceeds the density in the second layer. We also provide a procedure to calculate higher layer densities and prove that random trees have a higher limiting density in the first layer than regular trees. Finally, we compare densities between the first and second layer and between regular and random trees.

  10. Nash Equilibria in Random Games Imre Brny,1,2,

    E-Print Network [OSTI]

    Bárány, Imre

    Nash Equilibria in Random Games Imre Bárány,1,2, * Santosh Vempala,3, Adrian Vetta4, 1 Rényi.interscience.wiley.com). DOI 10.1002/rsa.20199 ABSTRACT: We consider Nash equilibria in 2-player random games and analyze a Nash equilibrium; on m × n payoff matrices, it runs in time O(m2 n log log n + n2 m log log m

  11. 2.017J / 1.015J Design of Systems Operating in Random Environments, Spring 2006

    E-Print Network [OSTI]

    Hover, Franz

    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 ...

  12. Invariant random graphs with iid degrees in a general geography

    E-Print Network [OSTI]

    Jonasson, Johan

    expectation). It is shown that if G has either polynomial growth or rapid growth, then such a random graph ball containing more than n vertices. With rapid growth we mean that the number of vertices in a ball or rapid growth. It is believed that no other growth rates are possible. When G has rapid growth

  13. Non-random gene flow: an underappreciated force in evolution

    E-Print Network [OSTI]

    Bolnick, Daniel I.

    , adaptation to climate change, biological invasion, and speciation. Giv- en the possible ubiquity and impacts-random gene flow and to more fully incorporate its effects into theory. Rethinking the homogenizing effect of gene flow Theory suggests that evolutionary change depends on the action of a limited number

  14. Robust protocols for securely expanding randomness and distributing keys using untrusted quantum devices

    E-Print Network [OSTI]

    Carl A. Miller; Yaoyun Shi

    2015-04-10

    Randomness is a vital resource for modern day information processing, especially for cryptography. A wide range of applications critically rely on abundant, high quality random numbers generated securely. Here we show how to expand a random seed at an exponential rate without trusting the underlying quantum devices. Our approach is secure against the most general adversaries, and has the following new features: cryptographic quality output security, tolerating a constant level of implementation imprecision, requiring only a constant size quantum memory for the honest implementation, and allowing a large natural class of constructions. In conjunct with a recent work by Chung, Shi and Wu (QIP 2014), it also leads to robust unbounded expansion using just 2 multi-part devices. When adapted for distributing cryptographic keys, our method achieves, for the first time, exponential expansion combined with cryptographic security and noise tolerance. The proof proceeds by showing that the Renyi divergence of the outputs of the protocol (for a specific bounding operator) decreases linearly as the protocol iterates. At the heart of the proof are a new uncertainty principle on quantum measurements, and a method for simulating trusted measurements with untrusted devices.

  15. VOLUME 88, NUMBER 19 P H Y S I C A L R E V I E W L E T T E R S 13 MAY 2002 Time-Frequency Characterization of Femtosecond Extreme Ultraviolet Pulses

    E-Print Network [OSTI]

    Keller, Ursula

    , Sweden 2 Institute of Physics and Astronomy, University of Aarhus, DK-8000 Aarhus C, Denmark 3 Department (Received 14 November 2001; published 25 April 2002) We present energy-resolved crossRevLett.88.193901 PACS numbers: 42.65.Ky, 32.80.Rm The production of high-order harmonics by an intense laser

  16. Concentration statistics for transport in random media Marco Dentz*

    E-Print Network [OSTI]

    Bolster, Diogo

    from a Langevin equation for the particle motion in a single disorder realization, we derive evolution transport problem. The governing equations describe multidimensional continuous time random walks whose waiting time distribution is given in terms of the disorder distribution. We find that the concentration

  17. Random wave functions and percolation

    E-Print Network [OSTI]

    E. Bogomolny; C. Schmit

    2007-08-31

    Recently it was conjectured that nodal domains of random wave functions are adequately described by critical percolation theory. In this paper we strengthen this conjecture in two respects. First, we show that, though wave function correlations decay slowly, a careful use of Harris' criterion confirms that these correlations are unessential and nodal domains of random wave functions belong to the same universality class as non critical percolation. Second, we argue that level domains of random wave functions are described by the non-critical percolation model.

  18. Shannon Capacity Ramsey Numbers

    E-Print Network [OSTI]

    Radziszowski, Stanislaw P.

    Shannon Capacity Ramsey Numbers Old links between Shannon and Ramsey New links between Shannon and Ramsey Bounds on Shannon Capacity and Ramsey Numbers from Product of Graphs Xiaodong Xu1 Stanislaw Institute of Technology, NY, USA March 2014 1/24 #12;Shannon Capacity Ramsey Numbers Old links between

  19. Motivation Random Performance Tableaux Special Performance Tableaux Conclusion Generating Random Performance Tableaux

    E-Print Network [OSTI]

    Bisdorff, Raymond

    Motivation Random Performance Tableaux Special Performance Tableaux Conclusion Generating Random Performance Tableaux Raymond Bisdorff University of Luxembourg, FSTC/CSC Mons, April, 2009 Motivation Random Performance Tableaux Special Performance Tableaux Conclusion Motivation Provide random instances

  20. Definition of a Random Variable Distribution Functions Properties of Distribution Functions Random Variables and Distribution Functions

    E-Print Network [OSTI]

    Watkins, Joseph C.

    Definition of a Random Variable Distribution Functions Properties of Distribution Functions Topic 7 Random Variables and Distribution Functions Distribution Functions 1 / 11 #12;Definition of a Random Variable Distribution Functions Properties of Distribution Functions Outline Definition of a Random

  1. Random Search Algorithms Zelda B. Zabinsky

    E-Print Network [OSTI]

    Del Moral , Pierre

    Random Search Algorithms Zelda B. Zabinsky April 5, 2009 Abstract Random search algorithms with convergence results in probability. Random search algorithms include simulated an- nealing, tabu search, genetic algorithms, evolutionary programming, particle swarm optimization, ant colony optimization, cross

  2. Correlations of Eigenvectors for Non-Hermitian Random-Matrix Models

    E-Print Network [OSTI]

    R. A. Janik; W. Noerenberg; M. A. Nowak; G. Papp; I. Zahed

    1999-02-23

    We establish a general relation between the diagonal correlator of eigenvectors and the spectral Green's function for non-hermitian random-matrix models in the large-N limit. We apply this result to a number of non-hermitian random-matrix models and show that the outcome is in good agreement with numerical results.

  3. SOLVING VIRUS STRUCTURES FROM XFEL DIFFRACTION PATTERNS OF RANDOM PARTICLE ORIENTATIONS USING ANGULAR

    E-Print Network [OSTI]

    Saldin, Dilano

    SOLVING VIRUS STRUCTURES FROM XFEL DIFFRACTION PATTERNS OF RANDOM PARTICLE ORIENTATIONS USING August 2013 #12;ABSTRACT SOLVING VIRUS STRUCTURES FROM XFEL DIFFRACTION PATTERNS OF RANDOM PARTICLE such as viruses. To quote from Caspar and Klug [2] "there are only a limited number of efficient designs possible

  4. Ancillary Statistics In a parametric model f (y; ) for a random variable

    E-Print Network [OSTI]

    Reid, Nancy

    Ancillary Statistics In a parametric model f (y; ) for a random variable or vector Y, a statistic A = a(Y) is ancillary for if the distribution of A does not depend on . As a very simple example, if Y is determined randomly, rather than being fixed in advance, then A = number of observations in Y is an ancillary

  5. A Randomized Multi-modulo RNS Architecture for Double-and-Add in ECC to prevent

    E-Print Network [OSTI]

    Sousa, Leonel

    1 A Randomized Multi-modulo RNS Architecture for Double-and-Add in ECC to prevent Power Analysis Number Systems (RNS) architectures to obfuscate the secure information. Random selection of moduli power analysis, while still providing all the benefits of RNS. In this paper, we show that Differential

  6. On Randomness in Quantum Mechanics

    E-Print Network [OSTI]

    Alberto C. de la Torre

    2007-07-19

    The quantum mechanical probability densities are compared with the probability densities treated by the theory of random variables. The relevance of their difference for the interpretation of quantum mechanics is commented.

  7. Random Selection for Drug Screening

    SciTech Connect (OSTI)

    Center for Human Reliability Studies

    2007-05-01

    Sampling is the process of choosing some members out of a group or population. Probablity sampling, or random sampling, is the process of selecting members by chance with a known probability of each individual being chosen.

  8. VOLUME 85, NUMBER 15 P H Y S I C A L R E V I E W L E T T E R S 9 OCTOBER 2000 Quantum State Reduction and Conditional Time Evolution

    E-Print Network [OSTI]

    Orozco, Luis A.

    , 42.50.Ct The seminal work of Hanbury-Brown and Twiss [1] marks the beginning of the systematic study-Brown and Twiss to record the conditional time evolution of the amplitude fluctuations of an electromagnetic wave

  9. Internet Usage Mining Using Random Forests

    E-Print Network [OSTI]

    Liu, Xuening

    2013-01-01

    Los Angeles Internet Usage Mining Using Random Forests Aof the Thesis Internet Usage Mining Using Random Forests bydata emerges, data mining is finally in the spotlight. This

  10. A Multi-Price Inventory Model with Random Discount Prices Mohammad Mahdi Tajbakhsh1, Chi-Guhn Lee1,3, Saeed Zolfaghari2

    E-Print Network [OSTI]

    Lee, Chi-Guhn

    A Multi-Price Inventory Model with Random Discount Prices Mohammad Mahdi Tajbakhsh1, Chi-Guhn Lee1 deal offers with a random discount price at random points in time. Assuming that the demand is constant over time, lead times are negligible, discount offerings follow a Poisson process, and discount price

  11. Hyperdiffusion of quantum waves in random photonic lattices

    E-Print Network [OSTI]

    Iomin, Alexander

    2015-01-01

    A quantum-mechanical analysis of hyper-fast (faster than ballistic) diffusion of a quantum wave packet in random optical lattices is presented. The main motivation of the presented analysis is experimental demonstrations of hyper-diffusive spreading of a wave packet in random photonic lattices [L. Levi \\textit{et al.}, Nature Phys. \\textbf{8}, 912 (2012)]. A rigorous quantum-mechanical calculation of the mean probability amplitude is suggested, and it is shown that the power law spreading of the mean squared displacement (MSD) is $\\sim t^{\\alpha}$, where $2potential $V(x,t)$, which describes random inhomogeneities of the medium. In particular, when the random potential is $\\delta$ correlated in time, the quantum wave packet spreads according Richardson turbulent diffusion with the MSD $\\sim t^3$. Hyper-diffusion with $\\alpha=12/5$ is also obtained for arbitrary correlation properties of the rand...

  12. One-time pad booster for Internet

    E-Print Network [OSTI]

    Geraldo A. Barbosa

    2007-04-11

    One-time pad encrypted files can be sent through Internet channels using current Internet protocols. However, the need for renewing shared secret keys make this method unpractical. This work shows how users can use a fast physical random generator based on fluctuations of a light field and the Internet channel to directly boost key renewals. The transmitted signals are deterministic but carries imprinted noise that cannot be eliminated by the attacker. Thus, a one-time pad for Internet can be made practical. Security is achieved without third parties and not relying on the difficulty of factoring numbers in primes. An informational fragility to be avoided is discussed. Information-theoretic analysis is presented and bounds for secure operation are determined.

  13. Record statistics in random vectors and quantum chaos

    E-Print Network [OSTI]

    Srivastava, Shashi C L; Jain, Sudhir R

    2012-01-01

    The record statistics of complex random states are analytically calculated, and shown that the probability of a record intensity is a Bernoulli process. The correlation due to normalization leads to a probability distribution of the records that is non-universal but tends to the Gumbel distribution asymptotically. The quantum standard map is used to study these statistics for the effect of correlations apart from normalization. It is seen that in the mixed phase space regime the number of intensity records is a power law in the dimensionality of the state as opposed to the logarithmic growth for random states.

  14. Number Theory Seminar

    E-Print Network [OSTI]

    $author.value

    2014-12-03

    Dec 3, 2014 ... TBA, Rachel Davis ... September 26, Rachel Davis .... Dessins d'Enfants · Indiana Pi Bill · Notes and Publications · Number Theory Seminar ...

  15. VOLUME 76, NUMBER 18 P H Y S I C A L R E V I E W L E T T E R S 29 APRIL 1996 Nonlinear Control of Dynamical Systems from Time Series

    E-Print Network [OSTI]

    Showalter, Kenneth

    developments and experimental applications of feedback control to nonlinear dynamical systems [2­11]. Recent of Dynamical Systems from Time Series Valery Petrov and Kenneth Showalter* Department of Chemistry, West of multidimensional, nonlinear single-input single-output systems is formulated in terms of an invariant hypersurface

  16. Tetrahedral colloidal clusters from random parking of bidisperse spheres

    E-Print Network [OSTI]

    Nicholas B. Schade; Miranda C. Holmes-Cerfon; Elizabeth R. Chen; Dina Aronzon; Jesse W. Collins; Jonathan A. Fan; Federico Capasso; Vinothan N. Manoharan

    2012-12-26

    Using experiments and simulations, we investigate the clusters that form when colloidal spheres stick irreversibly to -- or "park" on -- smaller spheres. We use either oppositely charged particles or particles labeled with complementary DNA sequences, and we vary the ratio $\\alpha$ of large to small sphere radii. Once bound, the large spheres cannot rearrange, and thus the clusters do not form dense or symmetric packings. Nevertheless, this stochastic aggregation process yields a remarkably narrow distribution of clusters with nearly 90% tetrahedra at $\\alpha=2.45$. The high yield of tetrahedra, which reaches 100% in simulations at $\\alpha=2.41$, arises not simply because of packing constraints, but also because of the existence of a long-time lower bound that we call the "minimum parking" number. We derive this lower bound from solutions to the classic mathematical problem of spherical covering, and we show that there is a critical size ratio $\\alpha_c=(1+\\sqrt{2})\\approx 2.41$, close to the observed point of maximum yield, where the lower bound equals the upper bound set by packing constraints. The emergence of a critical value in a random aggregation process offers a robust method to assemble uniform clusters for a variety of applications, including metamaterials.

  17. Time Constrained Randomized Path Planning Using Spatial Networks Christopher Lum*

    E-Print Network [OSTI]

    of Aeronautics and Astronautics University of Washington Seattle, WA 98195, USA lum@u.washington.edu Rolf Rysdyk** Department of Aeronautics and Astronautics University of Washington Seattle, WA 98195, USA rysdyk. Department of Aeronautics and Astronautics. **Assistant Professor. Department of Aeronautics and Astronautics

  18. Two regimes in the regularity of sunspot number

    SciTech Connect (OSTI)

    Shapoval, A.; Shnirman, M. [IEPT RAS, Profsoyuznaya str. 84/32, 117997 Moscow (Russian Federation); Le Mouël, J. L.; Courtillot, V. [IPGP, 1 rue Jussieu, F-75005, Paris (France)

    2013-12-20

    Sunspot numbers WN display quasi-periodical variations that undergo regime changes. These irregularities could indicate a chaotic system and be measured by Lyapunov exponents. We define a functional ? (an 'irregularity index') that is close to the (maximal) Lyapunov exponent for dynamical systems and well defined for series with a random component: this allows one to work with sunspot numbers. We compute ? for the daily WN from 1850 to 2012 within 4 yr sliding windows: ? exhibit sharp maxima at solar minima and secondary maxima at solar maxima. This pattern is reflected in the ratio R of the amplitudes of the main versus secondary peaks. Two regimes have alternated in the past 150 yr, R1 from 1850 to 1915 (large ? and R values) and R2 from 1935 to 2005 (shrinking difference between main and secondary maxima, R values between 1 and 2). We build an autoregressive model consisting of Poisson noise plus an 11 yr cycle and compute its irregularity index. The transition from R1 to R2 can be reproduced by strengthening the autocorrelation a of the model series. The features of the two regimes are stable for model and WN with respect to embedding dimension and delay. Near the time of the last solar minimum (?2008), the irregularity index exhibits a peak similar to the peaks observed before 1915. This might signal a regime change back from R2 to R1 and the onset of a significant decrease of solar activity.

  19. Detecting Tampering in Random Graphs

    E-Print Network [OSTI]

    Pinsky, Ross G

    2012-01-01

    Let $\\mathcal{G}_n=(V_n,E_n)$ be a growing sequence of deterministic finite graphs, with $V_n$ denoting the vertices and $E_n$ denoting the edges. Consider the random graph $\\mathcal{G}_n(p_n)=(V_n, E_n(p_n))$ obtained by including any given edge with probability $p_n$, independent of other edges, and let $P_n^{p_n}$ denote the corresponding probability measure on $\\mathcal{G}_n$. Now tamper with the random graph in some regular way. For example, if $\\mathcal{G}_n$ is the complete graph on $n$ vertices, so that $\\mathcal{G}_n(p_n)$ is the Erdos-Renyi graph, then one might tamper with it by disconnecting all the edges of a randomly chosen vertex, or by adding all the edges of a randomly chosen Hamiltonian path from $\\mathcal{G}_n$, or by adding all the edges of a randomly chosen clique of order $k_n$ from $\\mathcal{G}_n$. Denote the resulting induced measure on $\\mathcal{G}_n$ by $P_n^{p_n,\\text{tamper}}$. The tampering is called \\it detectable\\rm\\ if $\\lim_{n\\to\\infty}||P_n^{p_n,\\text{tamper}}-P_n^{p_n}||_{\\t...

  20. Particle-based simulations of steady-state mass transport at high P\\'eclet numbers

    E-Print Network [OSTI]

    Müller, Thomas; Rajah, Luke; Cohen, Samuel I A; Yates, Emma V; Vendruscolo, Michele; Dobson, Chrisopher M; Knowles, Tuomas P J

    2015-01-01

    Conventional approaches for simulating steady-state distributions of particles under diffusive and advective transport at high P\\'eclet numbers involve solving the diffusion and advection equations in at least two dimensions. Here, we present an alternative computational strategy by combining a particle-based rather than a field-based approach with the initialisation of particles in proportion to their flux. This method allows accurate prediction of the steady state and is applicable even at high P\\'eclet numbers where traditional particle-based Monte-Carlo methods starting from randomly initialised particle distributions fail. We demonstrate that generating a flux of particles according to a predetermined density and velocity distribution at a single fixed time and initial location allows for accurate simulation of mass transport under flow. Specifically, upon initialisation in proportion to their flux, these particles are propagated individually and detected by summing up their Monte-Carlo trajectories in p...

  1. Homogeneous Random Measures and Strongly Supermedian Kernels

    E-Print Network [OSTI]

    Fitzsimmons, Patrick J.

    . Keywords and phrases: Homogeneous random measure, additive functional, Kuznets* *ov measure, potential

  2. Renormalized energy concentration in random matrices

    E-Print Network [OSTI]

    Alexei Borodin; Sylvia Serfaty

    2012-10-23

    We define a "renormalized energy" as an explicit functional on arbitrary point configurations of constant average density in the plane and on the real line. The definition is inspired by ideas of [SS1,SS3]. Roughly speaking, it is obtained by subtracting two leading terms from the Coulomb potential on a growing number of charges. The functional is expected to be a good measure of disorder of a configuration of points. We give certain formulas for its expectation for general stationary random point processes. For the random matrix $\\beta$-sine processes on the real line (beta=1,2,4), and Ginibre point process and zeros of Gaussian analytic functions process in the plane, we compute the expectation explicitly. Moreover, we prove that for these processes the variance of the renormalized energy vanishes, which shows concentration near the expected value. We also prove that the beta=2 sine process minimizes the renormalized energy in the class of determinantal point processes with translation invariant correlation kernels.

  3. Random sequential adsorption of tetramers

    E-Print Network [OSTI]

    Micha? Cie?la

    2013-06-12

    Adsorption of tetramer built of four identical spheres was studied numerically using the Random Sequential Adsorption (RSA) algorithm. Tetramers were adsorbed on a two dimensional, flat and homogeneous surface. Two different models of the adsorbate were investigated: a rhomboid and a square one; monomer centres were put on vertices of rhomboids and squares, respectively. Numerical simulations allow to establish the maximal random coverage ratio as well as the Available Surface Function (ASF), which is crucial for determining kinetics of the adsorption process. These results were compared with data obtained experimentally for KfrA plasmid adsorption. Additionally, the density autocorrelation function was measured.

  4. The deterministic chaos and random noise in turbulent jet

    SciTech Connect (OSTI)

    Yao, Tian-Liang; Liu, Hai-Feng Xu, Jian-Liang; Li, Wei-Feng

    2014-06-01

    A turbulent flow is usually treated as a superposition of coherent structure and incoherent turbulence. In this paper, the largest Lyapunov exponent and the random noise in the near field of round jet and plane jet are estimated with our previously proposed method of chaotic time series analysis [T. L. Yao, et al., Chaos 22, 033102 (2012)]. The results show that the largest Lyapunov exponents of the round jet and plane jet are in direct proportion to the reciprocal of the integral time scale of turbulence, which is in accordance with the results of the dimensional analysis, and the proportionality coefficients are equal. In addition, the random noise of the round jet and plane jet has the same linear relation with the Kolmogorov velocity scale of turbulence. As a result, the random noise may well be from the incoherent disturbance in turbulence, and the coherent structure in turbulence may well follow the rule of chaotic motion.

  5. Big Numbers | Jefferson Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    with a length of 35 cm, which certainly helps . With Avogadro's number and the density of liquid hydrogen, we have about 1024 protons per cm2. We then take the beam of 160...

  6. KPA Activity Number

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    September 2002 Page 1 KPA Activity Number KPA Activity SEM Section SME Work Product SQSE Web Site http:cio.doe.govsqse REQUIREMENTS MANAGEMENT RM-1 The software engineering...

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

    E-Print Network [OSTI]

    Peterson, Jonathon

    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

  8. Supersymmetry in Random Matrix Theory

    E-Print Network [OSTI]

    Thomas Guhr

    2010-05-06

    Supersymmetry is nowadays indispensable for many problems in Random Matrix Theory. It is presented here with an emphasis on conceptual and structural issues. An introduction to supermathematics is given. The Hubbard-Stratonovich transformation as well as its generalization and superbosonization are explained. The supersymmetric non-linear sigma model, Brownian motion in superspace and the color-flavor transformation are discussed.

  9. Application Form Reference Number

    E-Print Network [OSTI]

    Po, Lai-Man

    /yyyy) (/) Title and Description of License/ Certificate/Activity // Date of Award (mm/yyyy) (/) Name Degree/Level Achieved Major Full-time or Part-time Date of Award (mm/yyyy) (/) Period From (mm-time Date of Award (mm/yyyy) (/) Period From (mm/yyyy) (/) To (mm/yyyy) (/) School

  10. Randomness and Noise in Information Systems Hongchao Zhou

    E-Print Network [OSTI]

    Bruck, Jehoshua (Shuki)

    in real research. He has also devoted a great deal of time and energy to my personal growth. I feel with in the Molecular Programming Project. I was very fortunate to work with these smart people, and enjoyed #12;v all molecular systems, where randomness plays important and distinct roles. Motivated by applications

  11. Passive Tracer Dispersion with Random or Periodic Source \\Lambda

    E-Print Network [OSTI]

    Passive Tracer Dispersion with Random or Periodic Source \\Lambda Jinqiao Duan Clemson University sources on the pattern formation and long­time behavior of concentration pro­ files of passive tracers Introduction The dispersion of passive tracers (or passive scalars) occur in various geo­ physical

  12. Passive Tracer Dispersion with Random or Periodic Source

    E-Print Network [OSTI]

    Passive Tracer Dispersion with Random or Periodic Source Jinqiao Duan Clemson University sources on the pattern formation and long-time behavior of concentration pro- #12;les of passive tracers #12;1 Introduction The dispersion of passive tracers (or passive scalars) occur in various geo

  13. LYAPUNOV EXPONENTS FOR POSITION DEPENDENT RANDOM MAPS: FORMULAE AND APPLICATIONS.

    E-Print Network [OSTI]

    of the interval. We then apply our results to a financial market model with short-lived assets. 1. Introduction]. A random map is a discrete time dynamical system consisting of a collection of transformations {k our theoretical results to a financial market model with short- lived assets [5]. In particular, when

  14. Efficient Generation of Large Random Networks Vladimir Batagelj

    E-Print Network [OSTI]

    Brandes, Ulrik

    to randomly generate networks according to the most commonly used models. Their running time and space, biological networks, river basins, or social networks, have significantly increased the interest in modeling be gener- ated efficiently by presenting generators that are asymp- totically optimal both in terms

  15. Topological and Dynamical Complexity of Random Neural Networks

    E-Print Network [OSTI]

    Gilles Wainrib; Jonathan Touboul

    2013-03-15

    Random neural networks are dynamical descriptions of randomly interconnected neural units. These show a phase transition to chaos as a disorder parameter is increased. The microscopic mechanisms underlying this phase transition are unknown, and similarly to spin-glasses, shall be fundamentally related to the behavior of the system. In this Letter we investigate the explosion of complexity arising near that phase transition. We show that the mean number of equilibria undergoes a sharp transition from one equilibrium to a very large number scaling exponentially with the dimension on the system. Near criticality, we compute the exponential rate of divergence, called topological complexity. Strikingly, we show that it behaves exactly as the maximal Lyapunov exponent, a classical measure of dynamical complexity. This relationship unravels a microscopic mechanism leading to chaos which we further demonstrate on a simpler class of disordered systems, suggesting a deep and underexplored link between topological and dynamical complexity.

  16. The Relation Between the Number of Species and the Number of Individuals in a Random Sample of an Animal Population

    E-Print Network [OSTI]

    Stephens, David A.

    's Terms and Conditions of Use, available at http://www.jstor.org/page/info/about/policies/terms.jsp. JSTOR the discovery and use of these resources. For more information about JSTOR, please contact support),A. STEVENCORBET (British Museum,Natural History) AND C. B. WILLIAMS (RothamstedExperimental Station) (With 8

  17. Greedy randomized adaptive search procedure for traveling salesman problem 

    E-Print Network [OSTI]

    Lee, Seung Ho

    2006-08-16

    common problems in com- binatorial optimization. A number of prominent researchers have tried to attack this problem. The role of the TSP in the field is underlined by the fact that it is commonly accepted as the representative combinatorial optimization..., controlled randomization, efficient data structures, and preprocessing are also beneficial? [6]. Combined with rapid development of com- puter technology, more successful heuristic methods are being introduced at a high pace. Heuristic algorithms for the TSP...

  18. Transition to chaos in random neuronal networks

    E-Print Network [OSTI]

    Jonathan Kadmon; Haim Sompolinsky

    2015-08-26

    Firing patterns in the central nervous system often exhibit strong temporal irregularity and heterogeneity in their time averaged response properties. Previous studies suggested that these properties are outcome of an intrinsic chaotic dynamics. Indeed, simplified rate-based large neuronal networks with random synaptic connections are known to exhibit sharp transition from fixed point to chaotic dynamics when the synaptic gain is increased. However, the existence of a similar transition in neuronal circuit models with more realistic architectures and firing dynamics has not been established. In this work we investigate rate based dynamics of neuronal circuits composed of several subpopulations and random connectivity. Nonzero connections are either positive-for excitatory neurons, or negative for inhibitory ones, while single neuron output is strictly positive; in line with known constraints in many biological systems. Using Dynamic Mean Field Theory, we find the phase diagram depicting the regimes of stable fixed point, unstable dynamic and chaotic rate fluctuations. We characterize the properties of systems near the chaotic transition and show that dilute excitatory-inhibitory architectures exhibit the same onset to chaos as a network with Gaussian connectivity. Interestingly, the critical properties near transition depend on the shape of the single- neuron input-output transfer function near firing threshold. Finally, we investigate network models with spiking dynamics. When synaptic time constants are slow relative to the mean inverse firing rates, the network undergoes a sharp transition from fast spiking fluctuations and static firing rates to a state with slow chaotic rate fluctuations. When the synaptic time constants are finite, the transition becomes smooth and obeys scaling properties, similar to crossover phenomena in statistical mechanics

  19. Global temperature deviations as a random walk

    SciTech Connect (OSTI)

    Karner, O.

    1996-12-31

    Surface air temperature is the main parameter to represent the earth`s contemporary climate. Several historical temperature records on a global/monthly basis are available. Time-series analysis shows that they can be modelled via autoregressive moving average models closely connected to the classical random walk model. Fitted models emphasize a nonstationary character of the global/monthly temperature deviation from a certain level. The nonstationarity explains all trends and periods, found in the last century`s variability of global mean temperature. This means that the short-term temperature trends are inevitable and may have little in common with a currently increasing carbon dioxide amount. The calculations show that a reasonable understanding of the contemporary global mean climate is attainable, assuming random forcing to the climate system and treating temperature deviation as a response to it. The forcings occur due to volcanic eruptions, redistribution of cloudiness, variations in snow and ice covered areas, changes in solar output, etc. Their impact can not be directly estimated from changes of the earth`s radiation budget at the top of the atmosphere, because actual measurements represent mixture of the forcings and responses. Thus, it is impossible empirically to separate the impact of one particular forcing (e.g., that due to increase of CO{sub 2} amount) from the sequence of all existing forcings in the earth climate system. More accurate modelling involving main feedback loops is necessary to ease such a separation.

  20. Upper bounds on wavepacket spreading for random Jacobi matrices

    E-Print Network [OSTI]

    Svetlana Jitomirskaya; Hermann Schulz-Baldes

    2007-02-15

    A method is presented for proving upper bounds on the moments of the position operator when the dynamics of quantum wavepackets is governed by a random (possibly correlated) Jacobi matrix. As an application, one obtains sharp upper bounds on the diffusion exponents for random polymer models, coinciding with the lower bounds obtained in a prior work. The second application is an elementary argument (not using multiscale analysis or the Aizenman-Molchanov method) showing that under the condition of uniformly positive Lyapunov exponents, the moments of the position operator grow at most logarithmically in time.

  1. The non-trivial random walk of stock prices Gabriele La Spada,1, 2,

    E-Print Network [OSTI]

    The non-trivial random walk of stock prices Gabriele La Spada,1, 2, J. Doyne Farmer,2, 1 the random walk of prices by developing a simple model relating the properties of the signs and absolute values of individual price changes to the diffusion rate (volatility) of prices at longer time scales. We

  2. UCGE Reports Number 20284

    E-Print Network [OSTI]

    Calgary, University of

    ABSTRACT Oil and gas are global fuels obtained primarily from drilling wells in underground terrestrial reservoirs. Vertical drilling is preferred because of its simplicity and therefore low cost, but subsurfaceUCGE Reports Number 20284 Department of Geomatics Engineering Continuous Measurement-While-Drilling

  3. Student Code Number: Thermodynamics

    E-Print Network [OSTI]

    Feeny, Brian

    Student Code Number: Thermodynamics Ph.D. Qualifying Exam Department of Mechanical Engineering;Thermodynamics Qualifier January 2013 Problem 1 Air is compressed in an axial-flow compressor operating at steady of exergy destruction within the compressor, in kJ per kg of air flowing. #12;Thermodynamics Qualifier

  4. UCGE Reports Number 20146

    E-Print Network [OSTI]

    Calgary, University of

    in considerable operational cost savings for many exploration and open-pit mining companies in the energy sectorUCGE Reports Number 20146 Department of Geomatics Engineering Development of a Mobile Equipment Equipment Management System solution. In the open-pit mining industries there is a need for these companies

  5. Australia NO REGISTRATION NUMBER

    E-Print Network [OSTI]

    Portugal Romania Slovenia Spain Turkey UK USA Australia Austria Belgium Cyprus France Germany Greece#12;#12;Australia Austria Belgium Cyprus France Germany Greece Ireland Italy Japan Macedonia Ireland Italy Japan Macedonia Portugal Romania Slovenia Spain Turkey UK USA #12;NO REGISTRATION NUMBER 1

  6. KNOTS AND RANDOM WALKS IN VIBRATED GRANULAR CHAINS

    SciTech Connect (OSTI)

    E. BEN-NAIM; ET AL

    2000-08-01

    The authors study experimentally statistical properties of the opening times of knots in vertically vibrated granular chains. Our measurements are in good qualitative and quantitative agreement with a theoretical model involving three random walks interacting via hard core exclusion in one spatial dimension. In particular, the knot survival probability follows a universal scaling function which is independent of the chain length, with a corresponding diffusive characteristic time scale. Both the large-exit-time and the small-exit-time tails of the distribution are suppressed exponentially, and the corresponding decay coefficients are in excellent agreement with the theoretical values.

  7. EFFICIENT STOCHASTIC GALERKIN METHODS FOR RANDOM ...

    E-Print Network [OSTI]

    2008-09-16

    EFFICIENT STOCHASTIC GALERKIN METHODS FOR RANDOM. DIFFUSION EQUATIONS. DONGBIN XIU? AND JIE SHEN†. Abstract. We discuss in this ...

  8. Modeling and optimizing of the random atomic spin gyroscope drift based on the atomic spin gyroscope

    SciTech Connect (OSTI)

    Quan, Wei; Lv, Lin Liu, Baiqi

    2014-11-15

    In order to improve the atom spin gyroscope's operational accuracy and compensate the random error caused by the nonlinear and weak-stability characteristic of the random atomic spin gyroscope (ASG) drift, the hybrid random drift error model based on autoregressive (AR) and genetic programming (GP) + genetic algorithm (GA) technique is established. The time series of random ASG drift is taken as the study object. The time series of random ASG drift is acquired by analyzing and preprocessing the measured data of ASG. The linear section model is established based on AR technique. After that, the nonlinear section model is built based on GP technique and GA is used to optimize the coefficients of the mathematic expression acquired by GP in order to obtain a more accurate model. The simulation result indicates that this hybrid model can effectively reflect the characteristics of the ASG's random drift. The square error of the ASG's random drift is reduced by 92.40%. Comparing with the AR technique and the GP + GA technique, the random drift is reduced by 9.34% and 5.06%, respectively. The hybrid modeling method can effectively compensate the ASG's random drift and improve the stability of the system.

  9. Hydrodynamical random walker with chemotactic memory

    E-Print Network [OSTI]

    H. Mohammady; B. Esckandariun; A. Najafi

    2014-10-01

    A three-dimensional hydrodynamical model for a micro random walker is combined with the idea of chemotactic signaling network of E. coli. Diffusion exponents, orientational correlation functions and their dependence on the geometrical and dynamical parameters of the system are analyzed numerically. Because of the chemotactic memory, the walker shows superdiffusing displacements in all directions with the largest diffusion exponent for a direction along the food gradient. Mean square displacements and orientational correlation functions show that the chemotactic memory washes out all the signatures due to the geometrical asymmetry of the walker and statistical properties are asymmetric only with respect to the direction of food gradient. For different values of the memory time, the Chemotactic index (CI) is also calculated.

  10. Choosing a Random Peer [Extended Abstract

    E-Print Network [OSTI]

    Saia, Jared

    ­ damental statistical operation; a function which chooses a random peer can be used for many types collection by statistically rig­ orous sampling methods; to provide support for randomized, distributed algorithms over peer­to­peer networks; and to support the creation and maintenance of random links

  11. Choosing a Random Peer [Extended Abstract

    E-Print Network [OSTI]

    Saia, Jared

    - damental statistical operation; a function which chooses a random peer can be used for many types collection by statistically rig- orous sampling methods; to provide support for randomized, distributed algorithms over peer-to-peer networks; and to support the creation and maintenance of random links

  12. On the variance of linear statistics of Hermitian random matrices

    E-Print Network [OSTI]

    Chao Min; Yang Chen

    2015-11-03

    Linear statistics, a random variable build out of the sum of the evaluation of functions at the eigenvalues of a N times N random matrix,sum[j=1 to N]f(xj) or tr f(M), is an ubiquitous statistical characteristics in random matrix theory. Hermitian random matrix ensembles, under the eigenvalue-eigenvector decomposition give rise to the joint probability density functions of N random variables. We show that if f(.) is a polynomial of degree K, then the variance of trf(M), is of the form,sum[n=1 to K] n(d[n])square, and d[n] is related to the expansion coefficients c[n] of the polynomial f(x) =sum[n=0 to K] c[n] b Pn(x), where Pn(x) are polynomials of degree n, orthogonal with respect to the weights 1/[(b-x)(x-a)]^(1/2), [(b -x)(x -a)]^(1/2), [(b-x)(x-a)]^(1/2)/x; (0 < a < x < b), [(b-x)(x-a)]^(1/2)/[x(1-x)] ; (0 < a < x < b < 1), respectively.

  13. DARNS:A Randomized Multi-modulo RNS Architecture for Double-and-Add in ECC to prevent

    E-Print Network [OSTI]

    Sousa, Leonel

    DARNS:A Randomized Multi-modulo RNS Architecture for Double-and-Add in ECC to prevent Power-modulo Residue Number Systems (RNS) archi- tectures to obfuscate the secure information. Random selection to prevent power analy- sis, while still providing all the benefits of RNS. In this paper, we show

  14. Harold Donnelly Course Number: MA52300 Credits: Three Time

    E-Print Network [OSTI]

    2015-10-16

    mathematical physics, Laplace's equation, wave equation, heat equation. ... Prerequisites: one undergraduate course in each of the following topics: linear .... gas/plasma dynamics, radiative transfer, semiconductor modeling, or even social

  15. Number Sec CRN Days Time Room Instructor Office 16200 222 ...

    E-Print Network [OSTI]

    ... 109 67610 MWF 08:30AM-09:20AM PHYS 338 James Bates MATH 845 16010 ... B012 Jeffrey Beckley MATH 818 37300 001 42982 W 09:30AM-10:20AM EE ... 12:30PM-01:20PM SMTH 208 Nathanael Cox MATH 733 15800 005 68064 ...

  16. Number Sec CRN Days Time Room Instructor Office 10800 001 ...

    E-Print Network [OSTI]

    ... 18100 H02 23146 W 03:30PM-04:20PM UNIV 103 Britain Cox MATH 1034 ..... 45579 MWF 04:30PM-05:20PM UNIV 217 James McClure MATH 714 36600 ...

  17. Number Sec CRN Days Time Room Instructor Office 10800 001 ...

    E-Print Network [OSTI]

    ... MWF 10:30AM-11:20AM SMTH 201 Nicholas Morris MATH G136 15300 065 .... Jake Desmond MATH 701 16500 141 42956 R 02:30PM-03:20PM UNIV 219 ...

  18. Parking on a Random Tree

    E-Print Network [OSTI]

    H. Dehling; S. R. Fleurke; C. Kuelske

    2007-11-26

    Consider an infinite tree with random degrees, i.i.d. over the sites, with a prescribed probability distribution with generating function G(s). We consider the following variation of Renyi's parking problem, alternatively called blocking RSA: at every vertex of the tree a particle (or car) arrives with rate one. The particle sticks to the vertex whenever the vertex and all of its nearest neighbors are not occupied yet. We provide an explicit expression for the so-called parking constant in terms of the generating function.

  19. Random sets and confidence procedures

    E-Print Network [OSTI]

    Barnett, William A.

    1979-06-01

    ) —* (Y, -T, (Qe)eee) be a random set with Y C ^ ( 0 ) - {0} and with Qe the probability distribution of S induced on Y by P0. Assume that S is surjective. The relation of statistical confidence sets to the following definition will be investigated... of confidence procedures now can be defined. DEFINITION 6. Let S be a confidence procedure. Then S has (lower) confidence level y — inl{Q6{êe) \\ 6 ^ Q). If S is a confidence pro­ cedure, and if x E ST, then S(x) will be called a confidence subset of 0...

  20. Neither Name, Nor Number

    E-Print Network [OSTI]

    Federico Holik

    2011-12-20

    Since its origins, Quantum mechanics has presented problems with the concept of individuality. It is argued that quantum particles do not have individuality, and so, one can speak about "entities without identity". On the contrary, we claim that the problem of quantum non individuality goes deeper, and that one of its most important features is the fact that there are quantum systems for which particle number is not well defined. In this work, we continue this discussion in relation to the problem about the one and the many.

  1. On Some Zarankiewicz Numbers and Bipartite Ramsey Numbers for

    E-Print Network [OSTI]

    Radziszowski, Stanislaw P.

    On Some Zarankiewicz Numbers and Bipartite Ramsey Numbers for Quadrilateral Janusz Dybizba Ramsey number b(n1, · · · , nk) is the least positive integer b such that any coloring of the edges of Kb Ramsey numbers avoiding quadrilateral. In particular, we prove that b4(2) = 19, and establish new general

  2. Local random quantum circuits are approximate polynomial-designs

    E-Print Network [OSTI]

    Fernando G. S. L. Brandao; Aram W. Harrow; Michal Horodecki

    2015-08-13

    We prove that local random quantum circuits acting on n qubits composed of O(t^{10} n^2) many nearest neighbor two-qubit gates form an approximate unitary t-design. Previously it was unknown whether random quantum circuits were a t-design for any t > 3. The proof is based on an interplay of techniques from quantum many-body theory, representation theory, and the theory of Markov chains. In particular we employ a result of Nachtergaele for lower bounding the spectral gap of frustration-free quantum local Hamiltonians; a quasi-orthogonality property of permutation matrices; a result of Oliveira which extends to the unitary group the path-coupling method for bounding the mixing time of random walks; and a result of Bourgain and Gamburd showing that dense subgroups of the special unitary group, composed of elements with algebraic entries, are infty-copy tensor-product expanders. We also consider pseudo-randomness properties of local random quantum circuits of small depth and prove that circuits of depth O(t^{10}n) constitute a quantum t-copy tensor-product expander. The proof also rests on techniques from quantum many-body theory, in particular on the detectability lemma of Aharonov, Arad, Landau, and Vazirani. We give applications of the results to cryptography, equilibration of closed quantum dynamics, and the generation of topological order. In particular we show the following pseudo-randomness property of generic quantum circuits: Almost every circuit U of size O(n^k) on n qubits cannot be distinguished from a Haar uniform unitary by circuits of size O(n^{(k-9)/11}) that are given oracle access to U.

  3. Demonstration of Robust Quantum Gate Tomography via Randomized Benchmarking

    E-Print Network [OSTI]

    Blake R. Johnson; Marcus P. da Silva; Colm A. Ryan; Shelby Kimmel; Jerry M. Chow; Thomas A. Ohki

    2015-05-25

    Typical quantum gate tomography protocols struggle with a self-consistency problem: the gate operation cannot be reconstructed without knowledge of the initial state and final measurement, but such knowledge cannot be obtained without well-characterized gates. A recently proposed technique, known as randomized benchmarking tomography (RBT), sidesteps this self-consistency problem by designing experiments to be insensitive to preparation and measurement imperfections. We implement this proposal in a superconducting qubit system, using a number of experimental improvements including implementing each of the elements of the Clifford group in single `atomic' pulses and custom control hardware to enable large overhead protocols. We show a robust reconstruction of several single-qubit quantum gates, including a unitary outside the Clifford group. We demonstrate that RBT yields physical gate reconstructions that are consistent with fidelities obtained by randomized benchmarking.

  4. Joint probability distributions for projection probabilities of random orthonormal states

    E-Print Network [OSTI]

    L. Alonso; T. Gorin

    2015-10-19

    A finite dimensional quantum system for which the quantum chaos conjecture applies has eigenstates, which show the same statistical properties than the column vectors of random orthogonal or unitary matrices. Here, we consider the different probabilities for obtaining a specific outcome in a projective measurement, provided the system is in one of its eigenstates. We then give analytic expressions for the joint probability density for these probabilities, with respect to the ensemble of random matrices. In the case of the unitary group, our results can be applied, also, to the phenomenon of universal conductance fluctuations, where the same mathematical quantities describe partial conductances in a two-terminal mesoscopic scattering problem with a finite number of modes in each terminal.

  5. Bridges in the random-cluster model

    E-Print Network [OSTI]

    Elçi, Eren Metin; Fytas, Nikolaos G

    2015-01-01

    The random-cluster model, a correlated bond percolation model, unifies a range of important models of statistical mechanics in one description, including independent bond percolation, the Potts model and uniform spanning trees. By introducing a classification of edges based on their relevance to the connectivity we study the stability of clusters in this model. We derive several exact relations for general graphs that allow us to derive unambiguously the finite-size scaling behavior of the density of bridges and non-bridges. For percolation, we are also able to characterize the point for which clusters become maximally fragile and show that it is connected to the concept of the bridge load. Combining our exact treatment with further results from conformal field theory, we uncover a surprising behavior of the variance of the number of (non-)bridges, showing that these diverge in two dimensions below the value $4\\cos^2{(\\pi/\\sqrt{3})}=0.2315891\\cdots$ of the cluster coupling $q$. Finally, it is shown that a par...

  6. Random Matrix Theory What is a Random Matrix? A matrix whose elements xij are random

    E-Print Network [OSTI]

    Theory Other applications: Wireless communications Nuclear physics Finance Genetics . . . 4 #12;Rare, capacities show number of fibre pairs and bit rate in Mbit/ s Optical Fibre Submarine Systems North Atlantic

  7. On-Chip Random Spectrometer

    E-Print Network [OSTI]

    Redding, Brandon; Sarma, Raktim

    2013-01-01

    Light scattering in disordered media has been studied extensively due to its prevalence in natural and artificial systems [1]. In the field of photonics most of the research has focused on understanding and mitigating the effects of scattering, which are often detrimental. For certain applications, however, intentionally introducing disorder can actually improve the device performance, e.g., in photovoltaics optical scattering improves the efficiency of light harvesting [2-5]. Here, we utilize multiple scattering in a random photonic structure to build a compact on-chip spectrometer. The probe signal diffuses through a scattering medium generating wavelength-dependent speckle patterns which can be used to recover the input spectrum after calibration. Multiple scattering increases the optical pathlength by folding the paths in a confined geometry, enhancing the spectral decorrelation of speckle patterns and thus increasing the spectral resolution. By designing and fabricating the spectrometer on a silicon wafe...

  8. Dynamics of Random Boolean Networks with Constant Number of Parents and Asynchrony Generated by Stochastic Processes

    E-Print Network [OSTI]

    Matache, Dora

    for both the real system and the models under the various parameter combinations and processes. The results the real system they model. Knowing the long-run behavior of such networks would allow one to identify by Stochastic Processes Huimin Geng Advisor: Dora Matache Department of Computer Science University of Nebraska

  9. Maximizing the Number of Broadcast Operations in Random Geometric Ad-Hoc Wireless Networks

    E-Print Network [OSTI]

    Calamoneri, Tiziana

    of a node depends, in turn, on the energy power supplied to the node. In particular, the power Pv required by a node v to correctly transmit data to another station w must satisfy the inequality (see [24]): Pv dist, in some network models (like sensor networks), the adopted technology allows to have only few possible

  10. Maximizing the Number of Broadcast Operations in Static Random Geometric Ad-Hoc Networks

    E-Print Network [OSTI]

    Calamoneri, Tiziana

    -Verlag Berlin Heidelberg 2007 #12;248 T. Calamoneri et al. supplied to the node. In particular, the power Pv]) Pv dist(v, w)2 (1) where dist(v, w) is the Euclidean distance between v and w while is a constant, in some network models (like sensor networks), the adopted technology allows to have only few possible

  11. Asymptotics of Bernoulli random walks, bridges, excursions and meanders with a given number of peaks

    E-Print Network [OSTI]

    Marckert, Jean-François

    Introduction Let N = {0, 1, 2, 3, . . . } be the set of non­negative integers. For any n # N, we denote by W n the set of Bernoulli chains with n steps : W n = {S = (S(i)) 0#i#n : S(0) = 0, S(i + 1) = S(i) ± 1 for any n with n steps are defined by B n = {S : S # W n , S(n) = 0}, E n = {S : S # W n , S(n) = 0, S

  12. The domination number of on-line social networks and random geometric graphs

    E-Print Network [OSTI]

    Pralat, Pawel

    of graphs in the Facebook 100 data set, and these bounds are well-correlated with those predicted geometric graphs. 1. Introduction On-line social networks (or OSNs) such as Facebook have emerged as a hot-demographics are closer together in the space. We give the precise definition of the GEO-P model (actually, one of its

  13. A Provably Secure True Random Number Generator with Built-in Tolerance to Active Attacks

    E-Print Network [OSTI]

    Martin, Bill

    , W. J. Martin, D. R. Stinson {sunar,martin}@wpi.edu Electrical & Computer Engineering Mathematical of Computer Science University of Waterloo Waterloo Ontario, N2L 3G1 Canada June 10, 2005 Abstract This paper;Good TRNG design rests on the quality of three components: · Entropy Source: Various TRNG designs have

  14. Time-Homogeneous Diffusions with a Given Marginal at a Random Time

    E-Print Network [OSTI]

    on the occasion of his 60th birthday. e-mail: A.M.G.Cox@bath.ac.uk; web: www.maths.bath.ac.uk/mapamgc/ e-mail: D.Hobson@warwick.ac.uk; web: www.warwick.ac.uk/go/dhobson/ §e-mail: obloj@maths.ox.ac.uk; web: www.maths.ox.ac.uk/obloj/ 1 #12 Krein's spectral theory of strings. Both of the above proofs exploit deep known results. In the final

  15. Logarithmic Opinion Pools for Conditional Random Fields 

    E-Print Network [OSTI]

    Smith, Andrew

    2007-06-26

    Since their recent introduction, conditional random fields (CRFs) have been successfully applied to a multitude of structured labelling tasks in many different domains. Examples include natural language processing ...

  16. The random lattice as a regularization scheme

    E-Print Network [OSTI]

    B. Alles

    1994-12-05

    A semi-analytic method to compute the first coefficients of the renormalization group functions on a random lattice is introduced. It is used to show that the two-dimensional $O(N)$ non-linear $\\sigma$-model regularized on a random lattice has the correct continuum limit. A degree $\\kappa$ of ``randomness'' in the lattice is introduced and an estimate of the ratio $\\Lambda_{random}/\\Lambda_{regular}$ for two rather opposite values of $\\kappa$ in the $\\sigma$-model is also given. This ratio turns out to depend on $\\kappa$.

  17. MARINE RESEARCH Volume 56, Number 1

    E-Print Network [OSTI]

    Balmforth, Neil

    Journal of MARINE RESEARCH Volume 56, Number 1 Enhanced dispersion of near-inertial waves at San Diego, La Jolla, California, 92093- 0230, U.S.A. Journal of Marine Research, 56, 1­40, 1998 1 #12 the near-inertial energy in the mixed layer returns to backgroundlevels on a time scale of ten to twenty

  18. ANDERSON LOCALIZATION FOR TIME PERIODIC

    E-Print Network [OSTI]

    disorder, Anderson localization in Z d is stable un- der localized time-periodic perturbations by proving random Schrodinger operators at large disorder has been well known since the seminal work of Fr is approximated by the potential V . The equation governing the system is (1.5) i @ @t = (#1; + V ) on Z d #2

  19. Thermodynamics of protein folding: a random matrix formulation

    E-Print Network [OSTI]

    Pragya Shukla

    2010-10-16

    The process of protein folding from an unfolded state to a biologically active, folded conformation is governed by many parameters e.g the sequence of amino acids, intermolecular interactions, the solvent, temperature and chaperon molecules. Our study, based on random matrix modeling of the interactions, shows however that the evolution of the statistical measures e.g Gibbs free energy, heat capacity, entropy is single parametric. The information can explain the selection of specific folding pathways from an infinite number of possible ways as well as other folding characteristics observed in computer simulation studies.

  20. Dynamical Slowdown of Polymers in Laminar and Random Flows

    E-Print Network [OSTI]

    Antonio Celani; Alberto Puliafito; Dario Vincenzi

    2006-09-22

    The influence of an external flow on the relaxation dynamics of a single polymer is investigated theoretically and numerically. We show that a pronounced dynamical slowdown occurs in the vicinity of the coil-stretch transition, especially when the dependence on polymer conformation of the drag is accounted for. For the elongational flow, relaxation times are exceedingly larger than the Zimm relaxation time, resulting in the observation of conformation hysteresis. For random smooth flows hysteresis is not present. Yet, relaxation dynamics is significantly slowed down because of the large variety of accessible polymer configurations. The implications of these results for the modeling of dilute polymer solutions in turbulent flows are addressed.

  1. Alternating current response of carbon nanotubes with randomly distributed impurities

    SciTech Connect (OSTI)

    Hirai, Daisuke; Watanabe, Satoshi [Department of Materials Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-8656 (Japan); Yamamoto, Takahiro [Department of Electrical Engineering and Department of Liberal Arts (Physics), Tokyo University of Science, 6-3-1 Niijuku, Katsushika, Tokyo 125-8585 (Japan)

    2014-10-27

    The increasing need for nanodevices has necessitated a better understanding of the electronic transport behavior of nanomaterials. We therefore theoretically examine the AC transport properties of metallic carbon nanotubes with randomly distributed impurities. We find that the long-range impurity scattering increases the emittance, but does not affect the DC conductance. The estimated dwell time of electrons increases with the potential amplitudes. That is, multiple scattering by the impurities increases the kinetic inductance in proportion to the dwell time, which eventually increases the emittance. We believe that our findings can contribute significantly to nanodevice development.

  2. Lyapunov exponents for products of complex Gaussian random matrices

    E-Print Network [OSTI]

    Peter J. Forrester

    2012-06-10

    The exact value of the Lyapunov exponents for the random matrix product $P_N = A_N A_{N-1}...A_1$ with each $A_i = \\Sigma^{1/2} G_i^{\\rm c}$, where $\\Sigma$ is a fixed $d \\times d$ positive definite matrix and $G_i^{\\rm c}$ a $d \\times d$ complex Gaussian matrix with entries standard complex normals, are calculated. Also obtained is an exact expression for the sum of the Lyapunov exponents in both the complex and real cases, and the Lyapunov exponents for diffusing complex matrices.

  3. Selfattractive random polymers Remco van der Hofstad

    E-Print Network [OSTI]

    Klenke, Achim

    Self­attractive random polymers Remco van der Hofstad Stieltjes Institute of Mathematics Delft polymer of finite length in Zd . Its law is that of a finite simple random walk path in Zd receiving that for > the attraction dominates the repulsion, i.e., with high probability the polymer is contained in a finite box

  4. Contagious Sets in Random Graphs Uriel Feige

    E-Print Network [OSTI]

    Contagious Sets in Random Graphs Uriel Feige Michael Krivelevich Daniel Reichman August 10, 2014. A contagious set is a set whose activation results with the entire graph being active. Given a graph G, let m(G, 2) be the minimal size of a contagious set. We consider the binomial random graph G := G(n, p

  5. Cauchy's formulas for random walks in bounded domains

    SciTech Connect (OSTI)

    Mazzolo, Alain, E-mail: alain.mazzolo@cea.fr; Zoia, Andrea, E-mail: andrea.zoia@cea.fr [CEA/Saclay, DEN/DANS/DM2S/SERMA/LTSD, 91191 Gif-sur-Yvette (France); Mulatier, Clélia de, E-mail: clelia.demulatier@cea.fr [CEA/Saclay, DEN/DANS/DM2S/SERMA/LTSD, 91191 Gif-sur-Yvette and CNRS - Université Paris-Sud, LPTMS, UMR8626, 91405 Orsay Cedex (France)

    2014-08-01

    Cauchy's formula was originally established for random straight paths crossing a body B?R{sup n} and basically relates the average chord length through B to the ratio between the volume and the surface of the body itself. The original statement was later extended in the context of transport theory so as to cover the stochastic paths of Pearson random walks with exponentially distributed flight lengths traversing a bounded domain. Some heuristic arguments suggest that Cauchy's formula may also hold true for Pearson random walks with arbitrarily distributed flight lengths. For such a broad class of stochastic processes, we rigorously derive a generalized Cauchy's formula for the average length traveled by the walkers in the body, and show that this quantity depends indeed only on the ratio between the volume and the surface, provided that some constraints are imposed on the entrance step of the walker in B. Similar results are also obtained for the average number of collisions performed by the walker in B.

  6. Two Dimensional Honeycomb Materials: random fields, dissipation and fluctuations

    E-Print Network [OSTI]

    T. Frederico; O. Oliveira; W. de Paula; M. S. Hussein; T. R. Cardoso

    2015-12-13

    In this paper, we propose a method to describe the many-body problem of electrons in honeycomb materials via the introduction of random fields which are coupled to the electrons and have a Gaussian distribution. From a one-body approach to the problem, after integrating exactly the contribution of the random fields, one builds a non-hermitian and dissipative effective Hamiltonian with two-body interactions. Our approach introduces besides the usual average over the electron field a second average over the random fields. The interplay of two averages enables the definition of various types of Green's functions which allow the investigation of fluctuation-dissipation characteristics of the interactions that are a manifestation of the many-body problem. In the current work we study only the dissipative term, through the perturbative analysis of the dynamics associated the effective Hamiltonian generated by two different kinds of couplings. For the cases analysed, the eigenstates of the effective Hamiltonian are complex and, therefore, some of the states have a finite life time. Moreover, we also investigate, in the mean field approximation, the most general parity conserving coupling to the random fields and compute the width of charge carriers $\\Gamma$ as a function of the Fermi energy $E_F$. The theoretical prediction for $\\Gamma (E_F)$ is compared to the available experimental data for graphene. The good agreement between $\\Gamma_{theo}$ and $\\Gamma_{exp}$ suggests that description of the many-body problem associated to the electrons in honeycomb materials can indeed be done via the introduction of random fields.

  7. The Distribution of Ramsey Numbers

    E-Print Network [OSTI]

    Lane Clark; Frank Gaitan

    2014-11-10

    We prove that the number of integers in the interval [0,x] that are non-trivial Ramsey numbers r(k,n) (3 <= k <= n) has order of magnitude (x ln x)**(1/2).

  8. Ordered Ramsey numbers David Conlon

    E-Print Network [OSTI]

    Fox, Jacob

    Ordered Ramsey numbers David Conlon Jacob Fox Choongbum Lee Benny Sudakov§ Abstract Given a labeled graph H with vertex set {1, 2, . . . , n}, the ordered Ramsey number r with vertices appearing in the same order as in H. The ordered Ramsey number of a labeled graph H is at least

  9. Hypergraph Ramsey numbers David Conlon

    E-Print Network [OSTI]

    Fox, Jacob

    Hypergraph Ramsey numbers David Conlon Jacob Fox Benny Sudakov Abstract The Ramsey number rk(s, n). In this paper we obtain new estimates for several basic hypergraph Ramsey problems. We give a new upper bound-color Ramsey number r3(n, n, n), which is the minimum N such that every 3-coloring of the triples

  10. Data Compression with Prime Numbers

    E-Print Network [OSTI]

    Gordon Chalmers

    2005-11-16

    A compression algorithm is presented that uses the set of prime numbers. Sequences of numbers are correlated with the prime numbers, and labeled with the integers. The algorithm can be iterated on data sets, generating factors of doubles on the compression.

  11. USE OF MAILBOX APPROACH, VIDEO SURVEILLANCE, AND SHORT-NOTICE RANDOM INSPECTIONS TO ENHANCE DETECTION OF UNDECLARED LEU PRODUCTION AT GAS CENTRIFUGE ENRICHMENT PLANTS.

    SciTech Connect (OSTI)

    BOYER, B.D.; GORDON, D.M.; JO, J.

    2006-07-16

    Current safeguards approaches used by the IAEA at gas centrifuge enrichment plants (GCEPs) need enhancement in order to detect undeclared LEU production with adequate detection probability. ''Mailbox'' declarations have been used in the last two decades to verify receipts, production, and shipments at some bulk-handling facilities (e.g., fuel-fabrication plants). The operator declares the status of his plant to the IAEA on a daily basis using a secure ''Mailbox'' system such as a secure tamper-resistant computer. The operator agrees to hold receipts and shipments for a specified period of time, along with a specified number of annual inspections, to enable inspector access to a statistically large enough population of UF{sub 6} cylinders and fuel assemblies to achieve the desired detection probability. The inspectors can access the ''Mailbox'' during randomly timed inspections and then verify the operator's declarations for that day. Previously, this type of inspection regime was considered mainly for verifying the material balance at fuel-fabrication, enrichment, and conversion plants. Brookhaven National Laboratory has expanded the ''Mailbox'' concept with short-notice random inspections (SNRIs), coupled with enhanced video surveillance, to include declaration and verification of UF{sub 6} cylinder operational data to detect activities associated with undeclared LEU production at GCEPs. Since the ''Mailbox'' declarations would also include data relevant to material-balance verification, these randomized inspections would replace the scheduled monthly interim inspections for material-balance purposes; in addition, the inspectors could simultaneously perform the required number of Limited-Frequency Unannounced Access (LFUA) inspections used for HEU detection. This approach would provide improved detection capabilities for a wider range of diversion activities with not much more inspection effort than at present.

  12. THE FOURTH-ORDER CORRELATION FUNCTION OF A RANDOMLY ADVECTED PASSIVE SCALAR

    E-Print Network [OSTI]

    Lebedev, Vladimir

    THE FOURTH-ORDER CORRELATION FUNCTION OF A RANDOMLY ADVECTED PASSIVE SCALAR E. Balkovskya , M the Gaussianity: we obtain analytically the simultaneous fourth-order correlation function of . Explicit expressions for fourth-order objects, like (1 - 2)4 are derived. PACS numbers: 47.10.+g, 47.27.-i, 05.40.+j

  13. Scaling limits for the critical Fortuin-Kastelyn model on a random planar map II: local estimates and empty reduced word exponent

    E-Print Network [OSTI]

    Ewain Gwynne; Xin Sun

    2015-05-13

    We continue our study of the inventory accumulation introduced by Sheffield (2011), which encodes a random planar map decorated by a collection of loops sampled from the critical Fortuin-Kastelyn (FK) model. We prove various "local" estimates for the inventory accumulation model, i.e.\\ estimates for the precise number of symbols of a given type in a word sampled from the model. Using our estimates, we obtain the scaling limit of the associated two-dimensional random walk conditioned on the event that it stays in the first quadrant for one unit of time and ends up at a particular position in the interior of the first quadrant. We also obtain the exponent for the probability that a word of length $2n$ sampled from the inventory accumulation model corresponds to an empty reduced word. The estimates of this paper will be used in a subsequent paper to obtain the scaling limit of the random walk associated with a finite-volume FK planar map.

  14. Grant Title: INITIATIVE FOR MAXIMIZING STUDENT DEVELOPMENT (IMSD) (R25) Funding Opportunity Number: PAR-13-082. CFDA Number(s): 93.859.

    E-Print Network [OSTI]

    Farritor, Shane

    : PAR-13-082. CFDA Number(s): 93.859. Agency/Department: National Institutes of Health (NIH), National skills, communication skills, time-management, group learning opportunities, independent library or bench career choices with appropriate role models. The proposed research education prog

  15. How Can Random Noise Help Us

    E-Print Network [OSTI]

    2009-03-18

    Basics of Random Walk – 2. 0. 5. 10. 15. 20. 25. 30. 35. 40. 45. 50. ?5. ?4. ?3. ?2. ?1. 0 ..... Back to Parrondo's Paradox. Playing Game A. . winning prob = 0.495.

  16. Supply Chain Supernetworks With Random Demands

    E-Print Network [OSTI]

    Nagurney, Anna

    Supply Chain Supernetworks With Random Demands June Dong Ding Zhang School of Business State Field Warehouses: stocking points Customers, demand centers sinks Production/ purchase costs Inventory Customer Demand Customer Demand Retailer OrdersRetailer Orders Distributor OrdersDistributor Orders

  17. Electromagnetic wave propagation in random waveguides

    E-Print Network [OSTI]

    Ricardo Alonso; Liliana Borcea

    2013-10-18

    We study long range propagation of electromagnetic waves in random waveguides with rectangular cross-section and perfectly conducting boundaries. The waveguide is filled with an isotropic linear dielectric material, with randomly fluctuating electric permittivity. The fluctuations are weak, but they cause significant cumulative scattering over long distances of propagation of the waves. We decompose the wave field in propagating and evanescent transverse electric and magnetic modes with random amplitudes that encode the cumulative scattering effects. They satisfy a coupled system of stochastic differential equations driven by the random fluctuations of the electric permittivity. We analyze the solution of this system with the diffusion approximation theorem, under the assumption that the fluctuations decorrelate rapidly in the range direction. The result is a detailed characterization of the transport of energy in the waveguide, the loss of coherence of the modes and the depolarization of the waves due to cumulative scattering.

  18. Beta dose distribution for randomly packed microspheres 

    E-Print Network [OSTI]

    Urashkin, Alexander

    2007-04-25

    of radiation dose distribution when utilizing this technique. This study focuses on random packing of microspheres and seeks to determine dose distributions for specific cases. The Monte Carlo Neutral Particle code (MCNP) developed by Los Alamos National...

  19. Random Walks for Mesh Denoising Xianfang Sun

    E-Print Network [OSTI]

    Martin, Ralph R.

    Random Walks for Mesh Denoising Xianfang Sun Cardiff University, UK Beihang University, China Paul noise-free po- sitions. Generally, the vertex positions are the primary measured e-mail: Xianfang.Sun

  20. QCD, Symmetry Breaking and the Random Lattice

    E-Print Network [OSTI]

    Saul D. Cohen

    2006-02-15

    According to the Nielsen-Ninomiya No-Go theorem, the doubling of fermions on the lattice cannot be suppressed in a chiral theory. Whereas Wilson and staggered fermions suppress doublers with explicit breaking of chiral symmetry, the random lattice does so by spontaneous chiral symmetry breaking even in the free theory. I present results for meson masses, the chiral condensate and fermionic eigenvalues from simulations of quenched QCD on random lattices in four dimensions, focusing on chiral symmetry breaking.

  1. Random matrix ensembles associated with Lax matrices

    E-Print Network [OSTI]

    E. Bogomolny; O. Giraud; C. Schmit

    2009-04-30

    A method to generate new classes of random matrix ensembles is proposed. Random matrices from these ensembles are Lax matrices of classically integrable systems with a certain distribution of momenta and coordinates. The existence of an integrable structure permits to calculate the joint distribution of eigenvalues for these matrices analytically. Spectral statistics of these ensembles are quite unusual and in many cases give rigorously new examples of intermediate statistics.

  2. What Impedes Efficient Adoption of Products? Evidence from Randomized Variation in Sales Offers for Improved Cookstoves in Uganda

    E-Print Network [OSTI]

    Levine, David I.; Cotterman, Carolyn

    2012-01-01

    ambitious than our sales offer can achieve. It is important3 years or more? ” N Sales Offer Free Time Trial PaymentsRandomized Variation in Sales Offers for Improved Cookstoves

  3. On fluctuations of eigenvalues of random band matrices

    E-Print Network [OSTI]

    Mariya Shcherbina

    2015-04-22

    We consider the fluctuation of linear eigenvalue statistics of random band $n\\times n$ matrices whose entries have the form $\\mathcal{M}_{ij}=b^{-1/2}u^{1/2}(|i-j|)\\tilde w_{ij}$ with i.i.d. $w_{ij}$ possessing the $(4+\\varepsilon)$th moment, where the function $u$ has a finite support $[-C^*,C^*]$, so that $M$ has only $2C_*b+1$ nonzero diagonals. The parameter $b$ (called the bandwidth) is assumed to grow with $n$ in a way that $b/n\\to 0$. Without any additional assumptions on the growth of $b$ we prove CLT for linear eigenvalue statistics for a rather wide class of test functions. Thus we improve and generalize the results of the previous papers [8] and [11], where CLT was proven under the assumption $n>>b>>n^{1/2}$. Moreover, we develop a method which allows to prove automatically the CLT for linear eigenvalue statistics of the smooth test functions for almost all classical models of random matrix theory: deformed Wigner and sample covariance matrices, sparse matrices, diluted random matrices, matrices with heavy tales, etc.

  4. Extreme slowdowns for one-dimensional excited random walks

    E-Print Network [OSTI]

    2013-12-20

    Dec 20, 2013 ... Rate of growth of a transient cookie random walk. Electron. J. Probab. ... Excited random walk. Electron. Comm. Probab., 8:86–92 (elec- tronic) ...

  5. Stabilizing Topological Phases in Graphene via Random Adsorption...

    Office of Scientific and Technical Information (OSTI)

    Stabilizing Topological Phases in Graphene via Random Adsorption Prev Next Title: Stabilizing Topological Phases in Graphene via Random Adsorption Authors: Jiang, Hua ; Qiao,...

  6. Application of Random Vibration Theory Methodology for Seismic...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

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

  7. The Pursuit of Balance in Sequential Randomized Trials

    E-Print Network [OSTI]

    Guiteras, Raymond P.; Levine, David I.; Polley, Thomas H.

    2015-01-01

    2003). “The pursuit of balance using stratified and dynamicThe Pursuit of Balance in Sequential Randomized Trials ?Mikel (2001). “Randomization, balance, and the validity and

  8. Number

    Office of Legacy Management (LM)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefield Municipal Gas &SCE-SessionsSouthReport for the Weldon Spring,7=cr5rnP 7694 i+lJNew York,' , /v-i 2

  9. Is there quantum chaos in the prime numbers?

    E-Print Network [OSTI]

    Todd Timberlake; Jeffery Tucker

    2008-01-07

    A statistical analysis of the prime numbers indicates possible traces of quantum chaos. We have computed the nearest neighbor spacing distribution, number variance, skewness, and excess for sequences of the first N primes for various values of N. All four statistical measures clearly show a transition from random matrix statistics at small N toward Poisson statistics at large N. In addition, the number variance saturates at large lengths as is common for eigenvalue sequences. This data can be given a physical interpretation if the primes are thought of as eigenvalues of a quantum system whose classical dynamics is chaotic at low energy but regular at high energy. We discuss some difficulties with this interpretation in an attempt to clarify what kind of physical system might have the primes as its quantum eigenvalues.

  10. Distribution of phylogenetic diversity under random extinction

    E-Print Network [OSTI]

    Beata Faller; Fabio Pardi; Mike Steel

    2007-08-02

    Phylogenetic diversity is a measure for describing how much of an evolutionary tree is spanned by a subset of species. If one applies this to the (unknown) subset of current species that will still be present at some future time, then this `future phylogenetic diversity' provides a measure of the impact of various extinction scenarios in biodiversity conservation. In this paper we study the distribution of future phylogenetic diversity under a simple model of extinction (a generalized `field of bullets' model). We show that the distribution of future phylogenetic diversity converges to a normal distribution as the number of species grows (under mild conditions, which are necessary). We also describe an algorithm to compute the distribution efficiently, provided the edge lengths are integral, and briefly outline the significance of our findings for biodiversity conservation.

  11. Performance of wireless sensor networks under random node failures

    SciTech Connect (OSTI)

    Bradonjic, Milan [Los Alamos National Laboratory; Hagberg, Aric [Los Alamos National Laboratory; Feng, Pan [Los Alamos National Laboratory

    2011-01-28

    Networks are essential to the function of a modern society and the consequence of damages to a network can be large. Assessing network performance of a damaged network is an important step in network recovery and network design. Connectivity, distance between nodes, and alternative routes are some of the key indicators to network performance. In this paper, random geometric graph (RGG) is used with two types of node failure, uniform failure and localized failure. Since the network performance are multi-facet and assessment can be time constrained, we introduce four measures, which can be computed in polynomial time, to estimate performance of damaged RGG. Simulation experiments are conducted to investigate the deterioration of networks through a period of time. With the empirical results, the performance measures are analyzed and compared to provide understanding of different failure scenarios in a RGG.

  12. Randomized controlled trial of prenatal zinc supplementation and the development of fetal heart rate

    E-Print Network [OSTI]

    Dominici, Francesca

    [HRV], number of accelerations) and movements (number and amplitude of move- ment bouts, time spent, and greater HRV. Supplementation effects on HRV and accelerations were more pronounced af- ter 28 weeks

  13. Particle-based simulations of steady-state mass transport at high Péclet numbers

    E-Print Network [OSTI]

    Thomas Müller; Paolo Arosio; Luke Rajah; Samuel I. A. Cohen; Emma V. Yates; Michele Vendruscolo; Chrisopher M. Dobson; Tuomas P. J. Knowles

    2015-10-17

    Conventional approaches for simulating steady-state distributions of particles under diffusive and advective transport at high P\\'eclet numbers involve solving the diffusion and advection equations in at least two dimensions. Here, we present an alternative computational strategy by combining a particle-based rather than a field-based approach with the initialisation of particles in proportion to their flux. This method allows accurate prediction of the steady state and is applicable even at high P\\'eclet numbers where traditional particle-based Monte-Carlo methods starting from randomly initialised particle distributions fail. We demonstrate that generating a flux of particles according to a predetermined density and velocity distribution at a single fixed time and initial location allows for accurate simulation of mass transport under flow. Specifically, upon initialisation in proportion to their flux, these particles are propagated individually and detected by summing up their Monte-Carlo trajectories in predefined detection regions. We demonstrate quantitative agreement of the predicted concentration profiles with the results of experiments performed with fluorescent particles in microfluidic channels under continuous flow. This approach is computationally advantageous and readily allows non-trivial initial distributions to be considered. In particular, this method is highly suitable for simulating advective and diffusive transport in microfluidic devices.

  14. Effects of systematic phase errors on optimized quantum random-walk search algorithm

    E-Print Network [OSTI]

    Yu-Chao Zhang; Wan-Su Bao; Xiang Wang; Xiang-Qun Fu

    2015-01-09

    This paper researches how the systematic errors in phase inversions affect the success rate and the number of iterations in optimized quantum random-walk search algorithm. Through geometric description of this algorithm, the model of the algorithm with phase errors is established and the relationship between the success rate of the algorithm, the database size, the number of iterations and the phase error is depicted. For a given sized database, we give both the maximum success rate of the algorithm and the required number of iterations when the algorithm is in the presence of phase errors. Through analysis and numerical simulations, it shows that optimized quantum random-walk search algorithm is more robust than Grover's algorithm.

  15. Pipeline MT Instructions Identification Number

    E-Print Network [OSTI]

    Hong, Don

    Pipeline MT Instructions Identification Number For identification purposes, you will be assigned a special identification number. M# You can activate your MT email, login to PipelineMT to register for classes or pay tuition and fees. Activating the MTSU Email and PipelineMT accounts: Visit the website

  16. SYMBOLS FOR TIME = time variable

    E-Print Network [OSTI]

    Duchowski, Andrew T.

    =forever) Cost spent to build variation point i at time i = index over variation points #12;SYMBOLS FOR TIME to account for net present value of money r = assumed interest rate i = index over variation points Cost Expected cost summed over all relevant time intervals Cost spent to build variation point i at time r

  17. Exact asymptotics of the freezing transition of a logarithmically correlated random energy model

    E-Print Network [OSTI]

    Christian Webb

    2011-08-26

    We consider a logarithmically correlated random energy model, namely a model for directed polymers on a Cayley tree, which was introduced by Derrida and Spohn. We prove asymptotic properties of a generating function of the partition function of the model by studying a discrete time analogy of the KPP-equation - thus translating Bramson's work on the KPP-equation into a discrete time case. We also discuss connections to extreme value statistics of a branching random walk and a rescaled multiplicative cascade measure beyond the critical point.

  18. Heating Season Has Ended An Update On The Numbers

    E-Print Network [OSTI]

    . An Update On The Numbers The attached graphics illustrate electricity consumption over a number of years. As a reference point, electricity comprises 2/3rds of our total fuel costs. Consumption will vary from year)/May and September/October time-frames represent seasonal transition and an opportunity to save on fuel consumption

  19. Reverse Auction Bidding-Bid Time Intervals Analysis 

    E-Print Network [OSTI]

    Xiao, Mengyan

    2015-05-11

    the computer is bidding during the segment 1 of each section, it shall randomly select from 2 seconds to 23 seconds as its time-intervals. Rule 2, when the computer is bidding during the segment 2 of each section, it shall randomly select from 2 seconds to 9...

  20. Modelling Time

    E-Print Network [OSTI]

    Burra G. Sidharth

    2008-09-03

    We briefly review two concepts of time - the usual time associated with "being" and more recent ideas, answering to the description of "becoming". The approximation involved in the former is examined. Finally we argue that it is (unpredictable) fluctuations that underlie time.

  1. Random Surfers on a Web Encyclopedia

    E-Print Network [OSTI]

    Geigl, Florian; Hofmann-Wellenhof, Rainer; Walk, Simon; Strohmaier, Markus; Helic, Denis

    2015-01-01

    The random surfer model is a frequently used model for simulating user navigation behavior on the Web. Various algorithms, such as PageRank, are based on the assumption that the model represents a good approximation of users browsing a website. However, the way users browse the Web has been drastically altered over the last decade due to the rise of search engines. Hence, new adaptations for the established random surfer model might be required, which better capture and simulate this change in navigation behavior. In this article we compare the classical uniform random surfer to empirical navigation and page access data in a Web Encyclopedia. Our high level contributions are (i) a comparison of stationary distributions of different types of the random surfer to quantify the similarities and differences between those models as well as (ii) new insights into the impact of search engines on traditional user navigation. Our results suggest that the behavior of the random surfer is almost similar to those of users...

  2. A model and architecture for pseudo-random generation with applications to /dev/random

    E-Print Network [OSTI]

    International Association for Cryptologic Research (IACR)

    A model and architecture for pseudo-random generation with applications to /dev/random Boaz Barak@alum.mit.edu September 1, 2005 Abstract We present a formal model and a simple architecture for robust pseudorandom's entropy source. Our model and architecture have the following properties: · Resilience. The generator

  3. Mott law as lower bound for a random walk in a random environment

    E-Print Network [OSTI]

    , Germany 2 Institut fË?ur Mathematik, Technische UniversitË?at Berlin, 10623 Berlin, Germany 3 Fachbereich Physik, UniversitË?at Duisburg­Essen, 45117 Essen, Germany July 21, 2004 Abstract We consider a random. Furthermore the point process is furnished with independent random bounded energy marks. The transition rates

  4. Dynamics of Glass Forming Liquids with Randomly Pinned Particles

    E-Print Network [OSTI]

    Saurish Chakrabarty; Smarajit Karmakar; Chandan Dasgupta

    2015-05-12

    It is frequently assumed that in the limit of vanishing cooling rate, the glass transition phenomenon becomes a thermodynamic transition at a temperature $T_{K}$. However, with any finite cooling rate, the system falls out of equilibrium at temperatures near $T_g(>T_{K})$, implying that the very existence of the putative thermodynamic phase transition at $T_{K}$ can be questioned. Recent studies of systems with randomly pinned particles have hinted that the thermodynamic glass transition may be observed in simulations and experiments carried out for liquids with randomly pinned particles. This expectation is based on the results of approximate calculations that suggest that the temperature of the thermodynamic glass transition increases as the concentration of pinned particles is increased and it may be possible to equilibrate the system at temperatures near the increased transition temperature. We test the validity of this prediction through extensive molecular dynamics simulations of two model glass-forming liquids in the presence of random pinning. We fit the temperature-dependence of the structural relaxation time to the Vogel-Fulcher-Tammann form that predicts a divergence of the relaxation time at a temperature $T_{VFT}$ and identify this temperature with the thermodynamic transition temperature $T_K$. We find that $T_{VFT}$ does not show any sign of increasing with increasing concentration of pinned particles. The main effect of pinning is found to be a rapid decrease in the kinetic fragility of the system with increasing pin concentration. Implications of these observations for current theories of the glass transition are discussed.

  5. Motion at low Reynolds number

    E-Print Network [OSTI]

    Tam, Daniel See Wai, 1980-

    2008-01-01

    The work described in this thesis centers on inertialess motion at low Reynolds numbers at the crossroad between biofluids and microfluids. Here we address questions regarding locomotion of micro-swimmers, transport of ...

  6. Departmental Business Instrument Numbering System

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2005-01-27

    The Order prescribes the procedures for assigning identifying numbers to all Department of Energy (DOE) and National Nuclear Security Administration (NNSA) business instruments. Cancels DOE O 540.1. Canceled by DOE O 540.1B.

  7. Departmental Business Instrument Numbering System

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2000-12-05

    To prescribe procedures for assigning identifying numbers to all Department of Energy (DOE), including the National Nuclear Security Administration, business instruments. Cancels DOE 1331.2B. Canceled by DOE O 540.1A.

  8. MOTOR POOL RESERVATIONS Reservation Number:_______________

    E-Print Network [OSTI]

    Ottino, Julio M.

    of Department Chair or Organization Advisor: ________________________________________ Chart String Number: Fund: ______________________________________________________________________ Name of Department or Organization: _____________________________________________________ Name reservations require the "Organization Authorization for University Vehicles" form to be faxed to Motor Pool

  9. DETECTING TAMPERING IN A RANDOM HYPERCUBE ROSS G. PINSKY

    E-Print Network [OSTI]

    Pinsky, Ross

    DETECTING TAMPERING IN A RANDOM HYPERCUBE ROSS G. PINSKY Abstract. Consider the random hypercube Hn the following two ways of tampering with the random graph Hn 2 (pn): (i) choose a diameter path at random these tamperings are detectable asymptotically as n . 1. Introduction and Statement of Results Let Hn 2 = (Vn, en

  10. Random field models for hydraulic conductivity in ground water flow

    E-Print Network [OSTI]

    Meerschaert, Mark M.

    Random field models for hydraulic conductivity in ground water flow Special Session on Random random fields to interpolate sparse data on hydraulic conductivity. The result- ing random field is used and Probability, Michigan State U Hans-Peter Scheffler, Mathematics, Uni Siegen, Germany Remke Van Dam, Institute

  11. The Number of Same-Sex Marriages in a Perfectly Bisexual Population is Asymptotically Normal Shalosh B. EKHAD1

    E-Print Network [OSTI]

    Zeilberger, Doron

    The Number of Same-Sex Marriages in a Perfectly Bisexual Population is Asymptotically Normal attracted to either sex and chooses his or her mate according to other criteria. Also assume that everyone gets married. Then the expectation of the random variable "Number of same-sex marriages" is 2n (2 n - 1

  12. Quantum Time

    E-Print Network [OSTI]

    John Ashmead

    2010-05-05

    Normally we quantize along the space dimensions but treat time classically. But from relativity we expect a high level of symmetry between time and space. What happens if we quantize time using the same rules we use to quantize space? To do this, we generalize the paths in the Feynman path integral to include paths that vary in time as well as in space. We use Morlet wavelet decomposition to ensure convergence and normalization of the path integrals. We derive the Schr\\"odinger equation in four dimensions from the short time limit of the path integral expression. We verify that we recover standard quantum theory in the non-relativistic, semi-classical, and long time limits. Quantum time is an experiment factory: most foundational experiments in quantum mechanics can be modified in a way that makes them tests of quantum time. We look at single and double slits in time, scattering by time-varying electric and magnetic fields, and the Aharonov-Bohm effect in time.

  13. Steering random walks with kicked ultracold atoms

    E-Print Network [OSTI]

    Marcel Weiß; Caspar Groiseau; W. K. Lam; Raffaella Burioni; Alessandro Vezzani; Gil S. Summy; Sandro Wimberger

    2015-06-27

    A kicking sequence of the atom optics kicked rotor at quantum resonance can be interpreted as a quantum random walk in momentum space. We show how to steer such a random walk by applying a random sequence of intensities and phases of the kicking lattice chosen according to a probability distribution. This distribution converts on average into the final momentum distribution of the kicked atoms. In particular, it is shown that a power-law distribution for the kicking strengths results in a L\\'evy walk in momentum space and in a power-law with the same exponent in the averaged momentum distribution. Furthermore, we investigate the stability of our predictions in the context of a realistic experiment with Bose-Einstein condensates.

  14. Steering random walks with kicked ultracold atoms

    E-Print Network [OSTI]

    Weiß, Marcel; Lam, W K; Burioni, Raffaella; Vezzani, Alessandro; Summy, Gil S; Wimberger, Sandro

    2015-01-01

    A kicking sequence of the atom optics kicked rotor at quantum resonance can be interpreted as a quantum random walk in momentum space. We show how to steer such a random walk by applying a random sequence of intensities and phases of the kicking lattice chosen according to a probability distribution. This distribution converts on average into the final momentum distribution of the kicked atoms. In particular, it is shown that a power-law distribution for the kicking strengths results in a L\\'evy walk in momentum space and in a power-law with the same exponent in the averaged momentum distribution. Furthermore, we investigate the stability of our predictions in the context of a realistic experiment with Bose-Einstein condensates.

  15. Tuning the Quantum Efficiency of Random Lasers - Intrinsic Stokes-Shift and Gain

    E-Print Network [OSTI]

    Andreas Lubatsch; Regine Frank

    2015-10-24

    We report the theoretical analysis for tuning the quantum efficiency of solid state random lasers. Vollhardt-Woelfle theory of photonic transport in disordered non-conserving and open random media, is coupled to lasing dynamics and solved positionally dependent. The interplay of non-linearity and homogeneous non-radiative frequency conversion by means of a Stokes-shift leads to a reduction of the quantum efficiency of the random laser. At the threshold a strong decrease of the spot-size in the stationary state is found due to the increase of non-radiative losses. The coherently emitted photon number per unit of modal surface is also strongly reduced. This result allows for the conclusion that Stokes-shifts are not sufficient to explain confined and extended mode regimes.

  16. Detection efficiency and noise in semi-device independent randomness extraction protocol

    E-Print Network [OSTI]

    Hong-Wei Li; Zhen-Qiang Yin; Marcin Pawlowski; Guang-Can Guo; Zheng-Fu Han

    2015-02-05

    In this paper, we analyze several critical issues in semi-device independent quantum information processing protocol. In practical experimental realization randomness generation in that scenario is possible only if the efficiency of the detectors used is above a certain threshold. Our analysis shows that the critical detection efficiency is 0.7071 in the symmetric setup, while in the asymmetric setup if one of the bases has perfect critical detection efficiency then the other one can be arbitrarily close to 0. We also analyze the semi-device independent random number generation efficiency based on different averages of guessing probability. To generate more randomness, the proper averaging method should be applied. Its choice depends on the value of a certain dimension witness. More importantly, the general analytical relationship between the maximal average guessing probability and dimension witness is given.

  17. Pulse propagation in decorated random chains

    E-Print Network [OSTI]

    Upendra Harbola; Alexandre Rosas; Aldo H. Romero; Katja Lindenberg

    2010-05-05

    We study pulse propagation in one-dimensional chains of spherical granules decorated with small randomly-sized granules placed between bigger monodisperse ones. Such "designer chains" are of interest in efforts to control the behavior of the pulse so as to optimize its propagation or attenuation, depending on the desired application. We show that a recently proposed effective description of simple decorated chains can be extended to predict pulse properties in chains decorated with small granules of randomly chosen radii. Furthermore, we also show that the binary collision approximation can again be used to provide analytic results for this system.

  18. Random matrix approach to multivariate categorical data analysis

    E-Print Network [OSTI]

    Patil, Aashay

    2015-01-01

    Correlation and similarity measures are widely used in all the areas of sciences and social sciences. Often the variables are not numbers but are instead qualitative descriptors called categorical data. We define and study similarity matrix, as a measure of similarity, for the case of categorical data. This is of interest due to a deluge of categorical data, such as movie ratings, top-10 rankings and data from social media, in the public domain that require analysis. We show that the statistical properties of the spectra of similarity matrices, constructed from categorical data, follow those from random matrix theory. We demonstrate this approach by applying it to the data of Indian general elections and sea level pressures in North Atlantic ocean.

  19. Kentucky Natural Gas Number of Residential Consumers (Number of Elements)

    Gasoline and Diesel Fuel Update (EIA)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustments (Billion Cubic Feet) Wyoming963Residential Consumers (Number of Elements) Kentucky Natural Gas Number

  20. TRANSPORT NUMBER GRADIENTS AND SOLID ELECTROLYTE DEGRADATION

    E-Print Network [OSTI]

    De Jonghe, Lutgard C.

    2014-01-01

    NUMBER GRADIENTS AND SOLID ELECTROLYTE DEGRADATION LutgardNUMBER GRADIENTS AND SOLID ELECTROLYTE DEGRADATION LutgardNUMBER GRADIENTS AND SOLID ELECTROLYTE DEGRADATION Lutgard

  1. TRANSPORT NUMBER GRADIENTS AND SOLID ELECTROLYTE DEGRADATION

    E-Print Network [OSTI]

    De Jonghe, Lutgard C.

    2012-01-01

    NUMBER GRADIENTS AND SOLID ELECTROLYTE DEGRADATION LutgardNUMBER GRADIENTS AND SOLID ELECTROLYTE DEGRADATION LutgardNUMBER GRADIENTS AND SOLID ELECTROLYTE DEGRADATION Lutgard

  2. Experimental determination of Ramsey numbers

    E-Print Network [OSTI]

    Zhengbing Bian; Fabian Chudak; William G. Macready; Lane Clark; Frank Gaitan

    2013-08-14

    Ramsey theory is a highly active research area in mathematics that studies the emergence of order in large disordered structures. Ramsey numbers mark the threshold at which order first appears and are extremely difficult to calculate due to their explosive rate of growth. Recently, an algorithm that can be implemented using adiabatic quantum evolution has been proposed that calculates the two-color Ramsey numbers $R(m,n)$. Here we present results of an experimental implementation of this algorithm and show that it correctly determines the Ramsey numbers R(3,3) and $R(m,2)$ for $4\\leq m\\leq 8$. The R(8,2) computation used 84 qubits of which 28 were computational qubits. This computation is the largest experimental implementation of a scientifically meaningful adiabatic evolution algorithm that has been done to date.

  3. Texas Rice, Volume VII, Number

    E-Print Network [OSTI]

    2007-01-01

    Texas A&M University System Agricultural Research and Extension Center Beaumont, Texas September 2007 Volume VII Number 7 Texas Rice Nobel Peace Prize Recipient Dr. Norman Borlaug continued on page 4 September of 2003 was a time etched... Tabien, and Dr. Lee Tarpley. Four years ago this month, the Texas A&M Research and Exten- sion Center at Beaumont was hon- ored to welcome one of the most influential people in agriculture. Nobel Peace Prize recipient, Dr. Norman Borlaug, has a long...

  4. Upply Chain Supernetworks with Random Demands

    E-Print Network [OSTI]

    Nagurney, Anna

    Upply Chain Supernetworks with Random Demands June Dong & Ding Zhang School of Business State Warehouses: stocking points Field Warehouses: stocking points Customers, demand centers sinks Production Commerce and Value Chain Management, 1998 Customer Demand Customer Demand Retailer OrdersRetailer Orders

  5. Random Constraint Satisfaction: theory meets practice?

    E-Print Network [OSTI]

    Walsh, Toby

    , and Taylor demonstrated that the hardest search prob- lems often occur around a rapid transition for many di erent NP-complete problems. Experimental results about phase transition behaviour have come thick and fast since the publication of 2]. For example, in random 3-Sat, the phase transition

  6. QUANTUM CHAOS, CLASSICAL RANDOMNESS, AND BOHMIAN MECHANICS

    E-Print Network [OSTI]

    Goldstein, Sheldon

    QUANTUM CHAOS, CLASSICAL RANDOMNESS, AND BOHMIAN MECHANICS Detlef DË? urr* ,+ , Sheldon Goldstein of quantum theory, Bohmian mechanics, in which ``quantum chaos'' also arises solely from the dynamical law. Moreover, this occurs in a manner far simpler than in the classical case. KEY WORDS: Quantum chaos; quantum

  7. Distributed QR Factorization Based on Randomized Algorithms

    E-Print Network [OSTI]

    Zemen, Thomas

    Distributed QR Factorization Based on Randomized Algorithms Hana Strakov´a1 , Wilfried N. Gansterer of Algorithms Hana.Strakova@univie.ac.at, Wilfried.Gansterer@univie.ac.at 2 Forschungszentrum Telekommunication Wien, Austria Thomas.Zemen@ftw.at Abstract. Most parallel algorithms for matrix computations assume

  8. Positive Lyapunov exponent by a random perturbation

    E-Print Network [OSTI]

    Zeng Lian; Mikko Stenlund

    2010-12-20

    We study the effect of a random perturbation on a one-parameter family of dynamical systems whose behavior in the absence of perturbation is ill understood. We provide conditions under which the perturbed system is ergodic and admits a positive Lyapunov exponent, with an explicit lower bound, for a large and controlled set of parameter values.

  9. Random Walks and Nonlinear Dynamics in the

    E-Print Network [OSTI]

    Frey, Erwin

    in the experimental biophysics and state-of-the-art concepts of modern nonlinear dynamics and random-walk theory leading experts in cell biology and theoretical physics in order to tie recent advances: Visitors Program ­ Mandy Lochar MPI for the Physics of Complex Systems Nöthnitzer Str. 38, D-01187 Dresden

  10. RANDOMIZED SPARSE DIRECT SOLVERS 1. Introduction. Large ...

    E-Print Network [OSTI]

    2013-03-21

    Key words. randomized sparse solver, structured multifrontal method, skinny extend-add ... For example, for discretized elliptic equations in two dimen- ...... tions with modest accuracy, using the adaptive Algorithm 5 in MATLAB. ..... [36] S. Wang, M. V. de Hoop, and J. Xia, On 3D modeling of seismic wave propagation via a.

  11. Convergence properties of polynomial chaos approximations for L2 random variables.

    SciTech Connect (OSTI)

    Field, Richard V., Jr. (.,; .); Grigoriu, Mircea (Cornell University, Ithaca, NY)

    2007-03-01

    Polynomial chaos (PC) representations for non-Gaussian random variables are infinite series of Hermite polynomials of standard Gaussian random variables with deterministic coefficients. For calculations, the PC representations are truncated, creating what are herein referred to as PC approximations. We study some convergence properties of PC approximations for L{sub 2} random variables. The well-known property of mean-square convergence is reviewed. Mathematical proof is then provided to show that higher-order moments (i.e., greater than two) of PC approximations may or may not converge as the number of terms retained in the series, denoted by n, grows large. In particular, it is shown that the third absolute moment of the PC approximation for a lognormal random variable does converge, while moments of order four and higher of PC approximations for uniform random variables do not converge. It has been previously demonstrated through numerical study that this lack of convergence in the higher-order moments can have a profound effect on the rate of convergence of the tails of the distribution of the PC approximation. As a result, reliability estimates based on PC approximations can exhibit large errors, even when n is large. The purpose of this report is not to criticize the use of polynomial chaos for probabilistic analysis but, rather, to motivate the need for further study of the efficacy of the method.

  12. Signal statistics of phase dependent optical time domain reflectometry 

    E-Print Network [OSTI]

    Wojcik, Aleksander Karol

    2007-04-25

    The statistics of the phase dependent optical time-domain reflectometer have been analyzed. The optical fiber is modeled by the use of a discrete set of reflectors positioned randomly along the fiber. The statistics of the ...

  13. Maintaining dynamic sequences under equalitytests in polylogarithmic time

    E-Print Network [OSTI]

    Maintaining dynamic sequences under equality­tests in polylogarithmic time K. Mehlhorn R. Sundar C. Uhrig January 16, 1996 Abstract We present a randomized and a deterministic data structure

  14. Kodama time

    E-Print Network [OSTI]

    Abreu, Gabriel

    2010-01-01

    In a general time-dependent (3+1)-dimensional spherically symmetric spacetime, the so-called Kodama vector is a naturally defined geometric quantity that is timelike outside the evolving horizon and so defines a preferred class of fiducial observers. However the Kodama vector does not by itself define any preferred notion of time. We demonstrate that a preferred time coordinate - which we shall call Kodama time - can be introduced by taking the additional step of applying the Clebsch decomposition theorem to the Kodama vector. We thus construct a geometrically preferred coordinate system for any time-dependent spherically symmetric spacetime, and explore its properties. In particular we use this formalism to construct a general class of conservation laws, generalizing Kodama's energy flux. We study the geometrically preferred fiducial observers, and demonstrate that it is possible to define and calculate a generalized notion of surface gravity that is valid throughout the entire evolving spacetime. Furthermor...

  15. Thermalized Non-Equilibrated Matter against Random Matrix Theory, Quantum Chaos and Direct Interaction: Warming up

    E-Print Network [OSTI]

    S. Kun; Y. Li; M. H. Zhao; M. R. Huang

    2013-07-17

    The idea of a thermalized non-equilibrated state of matter offers a conceptually new understanding of the strong angular asymmetry. In this compact review we present some clarifications, corrections and further developments of the approach, and provide a brief account of results previously discussed but not reported in the literature. The cross symmetry compound nucleus $S$-matrix correlations are obtained (i) starting from the unitary $S$-matrix representation, (ii) by explicitly taking into account a process of energy equilibration, and (iii) without taking the thermodynamic limit of an infinite number of particles in the thermalized system. It is conjectured that the long phase memory is due to the exponentially small total spin off-diagonal resonance intensity correlations. This manifestly implies that the strong angular asymmetry intimately relates to extremely small deviations of the eigenfunction distribution from Gaussian law. The spin diagonal resonance intensity correlations determine a new time/energy scale for a validity of random matrix theory. Its definition does not involve overlaps of the many-body interacting configurations with shell model non-interacting states and thus is conceptually different from the physical meaning (inverse energy relaxation time) of the spreading widths introduced by Wigner. Exact Gaussian distribution of the resonance wave functions corresponds to the instantaneous phase relaxation. We invite the nuclear reaction community for the competition to describe, as the first challenge, the strong forward peaking in the typically evaporation part of the proton spectra. This is necessary to initiate revealing long-term misconduct in the heavily cross-disciplinary field, also important for nuclear industry applications.

  16. A Markov Random Field model of contamination source identification in porous media flow

    E-Print Network [OSTI]

    Zabaras, Nicholas J.

    A Markov Random Field model of contamination source identification in porous media flow Jingbo Wang A contamination source identification problem in constant porous media flow is addressed by solving the advection-dispersion equation (ADE) with a hierarchical Bayesian computation method backward through time. The contaminant

  17. On the Power of Randomization in Algorithmic Mechanism Design Shahar Dobzinski

    E-Print Network [OSTI]

    Sandholm, Tuomas W.

    On the Power of Randomization in Algorithmic Mechanism Design Shahar Dobzinski Department Stanford University shaddin@cs.stanford.edu Abstract In many settings the power of truthful mechanisms that no polynomial-time truthful deterministic mechanism provides an approximation ratio better than 2. We also show

  18. Rhythm and Randomness in Human Contact Mervyn P. Freeman, Nicholas W. Watkins

    E-Print Network [OSTI]

    Hand, Steven

    (pdf) p(t) of times between human contact is well approximated by a truncated power law i.e. p(t) t-(1 argued that human mobility patterns resemble truncated L´evy walks (TLW). The TLW paradigm representsRhythm and Randomness in Human Contact Mervyn P. Freeman, Nicholas W. Watkins British Antarctic

  19. On the Unification of Random Matrix Theories

    E-Print Network [OSTI]

    Rupert A Small

    2015-03-31

    A new method involving particle diagrams is introduced and developed into a rigorous framework for carrying out embedded random matrix calculations. Using particle diagrams and the attendant methodology including loop counting it becomes possible to calculate the fourth, sixth and eighth moments of embedded ensembles in a straightforward way. The method, which will be called the method of particle diagrams, proves useful firstly by providing a means of classifying the components of moments into particle paths, or loops, and secondly by giving a simple algorithm for calculating the magnitude of combinatorial expressions prior to calculating them explicitly. By confining calculations to the limit case $m \\ll l\\to\\infty$ this in many cases provides a sufficient excuse not to calculate certain terms at all, since it can be foretold using the method of particle diagrams that they will not survive in this asymptotic regime. Applying the method of particle diagrams washes out a great deal of the complexity intrinsic to the problem, with sufficient mathematical structure remaining to yield limiting statistics for the unified phase space of random matrix theories. Finally, since the unified form of random matrix theory is essentially the set of all randomised k-body potentials, it should be no surprise that the early statistics calculated for the unified random matrix theories in some instances resemble the statistics currently being discovered for quantum spin hypergraphs and other randomised potentials on graphs [HMH05,ES14,KLW14]. This is just the beginning for studies into the field of unified random matrix theories, or embedded ensembles, and the applicability of the method of particle diagrams to a wide range of questions as well as to the more exotic symmetry classes, such as the symplectic ensembles, is still an area of open-ended research.

  20. A novel model and estimation method for the individual random component of earthquake ground-motion relations

    E-Print Network [OSTI]

    Raschke, Mathias

    2015-01-01

    In this paper, I introduce a novel approach to modelling the individual random component (also called the intra-event uncertainty) of a ground-motion relation (GMR), as well as a novel approach to estimating the corresponding parameters. In essence, I contend that the individual random component is reproduced adequately by a simple stochastic mechanism of random impulses acting in the horizontal plane, with random directions. The random number of impulses was Poisson distributed. The parameters of the model were estimated according to a proposal by Raschke (2013a), with the sample of random difference xi=ln(Y1)-ln(Y2), in which Y1 and Y2 are the horizontal components of local ground-motion intensity. Any GMR element was eliminated by subtraction, except the individual random components. In the estimation procedure the distribution of difference xi was approximated by combining a large Monte Carlo simulated sample and Kernel smoothing. The estimated model satisfactorily fitted the difference xi of the sample o...

  1. Constrained Ramsey Numbers of Graphs

    E-Print Network [OSTI]

    Jiang, Tao

    Constrained Ramsey Numbers of Graphs Robert E. Jamison,1 Tao Jiang,2* and Alan C. H. Ling3 1-like trees. � 2002 Wiley Periodicals, Inc. J Graph Theory 42: 1­16, 2003 Keywords: Ramsey; monochromatic edges have the same color and rainbow iff all of its edges have different colors. In classical Ramsey

  2. Swimming by numbers QUANTUM CONTROL

    E-Print Network [OSTI]

    Mahadevan, L.

    flow, providing key qualitative insight in fluid mechanics. For example, the so-called Reynolds number be described by a universal mechanical principle seems optimistic -- if not entirely unrealistic. Now, however and pressure forces relevant for net propulsion. A measure of the thrust force is given by the mass

  3. Quantum time

    E-Print Network [OSTI]

    Giovannetti, Vittorio

    We give a consistent quantum description of time, based on Page and Wootters’s conditional probabilities mechanism, which overcomes the criticisms that were raised against similar previous proposals. In particular we show ...

  4. Chow Time 

    E-Print Network [OSTI]

    Unknown

    2011-09-05

    -1 THE PREDICTION OF BUS ARRIVAL TIME USING AUTOMATIC VEHICLE LOCATION SYSTEMS DATA A Dissertation by RAN HEE JEONG Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree... of DOCTOR OF PHILOSOPHY December 2004 Major Subject: Civil Engineering THE PREDICTION OF BUS ARRIVAL TIME USING AUTOMATIC VEHICLE LOCATION SYSTEMS DATA A Dissertation by RAN HEE JEONG Submitted to Texas A...

  5. Parameters affecting the resilience of scale-free networks to random failures.

    SciTech Connect (OSTI)

    Link, Hamilton E.; LaViolette, Randall A.; Lane, Terran (University of New Mexico, Albuquerque, NM); Saia, Jared (University of New Mexico, Albuquerque, NM)

    2005-09-01

    It is commonly believed that scale-free networks are robust to massive numbers of random node deletions. For example, Cohen et al. in (1) study scale-free networks including some which approximate the measured degree distribution of the Internet. Their results suggest that if each node in this network failed independently with probability 0.99, most of the remaining nodes would still be connected in a giant component. In this paper, we show that a large and important subclass of scale-free networks are not robust to massive numbers of random node deletions. In particular, we study scale-free networks which have minimum node degree of 1 and a power-law degree distribution beginning with nodes of degree 1 (power-law networks). We show that, in a power-law network approximating the Internet's reported distribution, when the probability of deletion of each node is 0.5 only about 25% of the surviving nodes in the network remain connected in a giant component, and the giant component does not persist beyond a critical failure rate of 0.9. The new result is partially due to improved analytical accommodation of the large number of degree-0 nodes that result after node deletions. Our results apply to power-law networks with a wide range of power-law exponents, including Internet-like networks. We give both analytical and empirical evidence that such networks are not generally robust to massive random node deletions.

  6. The role of the Kubo number in two-component turbulence

    SciTech Connect (OSTI)

    Qin, G. [State Key Laboratory of Space Weather, Center for Space Science and Applied Research, Chinese Academy of Sciences, Beijing 100190 (China)] [State Key Laboratory of Space Weather, Center for Space Science and Applied Research, Chinese Academy of Sciences, Beijing 100190 (China); Shalchi, A. [Department of Physics and Astronomy, University of Manitoba, Winnipeg, Manitoba R3T 2N2 (Canada)] [Department of Physics and Astronomy, University of Manitoba, Winnipeg, Manitoba R3T 2N2 (Canada)

    2013-09-15

    We explore the random walk of magnetic field lines in two-component turbulence by using computer simulations. It is often assumed that the two-component model provides a good approximation for solar wind turbulence. We explore the dependence of the field line diffusion coefficient on the Kubo number which is a fundamental and characteristic quantity in the theory of turbulence. We show that there are two transport regimes. One is the well-known quasilinear regime in which the diffusion coefficient is proportional to the Kubo number squared, and the second one is a nonlinear regime in which the diffusion coefficient is directly proportional to the Kubo number. The so-called percolative transport regime which is often discussed in the literature cannot be found. The numerical results obtained in the present paper confirm analytical theories for random walking field lines developed in the past.

  7. From Boltzmann to random matrices and beyond

    E-Print Network [OSTI]

    Djalil Chafaï

    2015-02-26

    These expository notes propose to follow, across fields, some aspects of the concept of entropy. Starting from the work of Boltzmann in the kinetic theory of gases, various universes are visited, including Markov processes and their Helmholtz free energy, the Shannon monotonicity problem in the central limit theorem, the Voiculescu free probability theory and the free central limit theorem, random walks on regular trees, the circular law for the complex Ginibre ensemble of random matrices, and finally the asymptotic analysis of mean-field particle systems in arbitrary dimension, confined by an external field and experiencing singular pair repulsion. The text is written in an informal style driven by energy and entropy. It aims to be recreative and to provide to the curious readers entry points in the literature, and connections across boundaries.

  8. Stochastic 3D modeling of the microstructure of lithium-ion battery anodes via Gaussian random fields on

    E-Print Network [OSTI]

    Schmidt, Volker

    Stochastic 3D modeling of the microstructure of lithium-ion battery anodes via Gaussian random microstructures of lithium-ion battery anodes, which can serve as input for the simulations. We introduce the use; 1. Introduction Lithium-ion batteries used in electric vehicles need to fulfill a number

  9. Delone dynamical systems and associated random operators

    E-Print Network [OSTI]

    Daniel Lenz; Peter Stollmann

    2002-05-13

    We carry out a careful study of basic topological and ergodic features of Delone dynamical systems. We then investigate the associated topological groupoids and in particular their representations on certain direct integrals with non constant fibres. Via non-commutative-integration theory these representations give rise to von Neumann algebras of random operators. Features of these algebras and operators are discussed. Restricting our attention to a certain subalgebra of tight binding operators, we then discuss a Shubin trace formula.

  10. Chopped random-basis quantum optimization

    E-Print Network [OSTI]

    Tommaso Caneva; Tommaso Calarco; Simone Montangero

    2011-08-22

    In this work we describe in detail the "Chopped RAndom Basis" (CRAB) optimal control technique recently introduced to optimize t-DMRG simulations [arXiv:1003.3750]. Here we study the efficiency of this control technique in optimizing different quantum processes and we show that in the considered cases we obtain results equivalent to those obtained via different optimal control methods while using less resources. We propose the CRAB optimization as a general and versatile optimal control technique.

  11. Prediction and Estimation of Random Fields 

    E-Print Network [OSTI]

    Kohli, Priya

    2012-10-19

    ; z2) = 1X k=0 1X ‘=0 bk;‘z k 1z ‘ 2; 1(z1; z2) = 1X k=0 1X ‘=0 ak;‘z k 1z ‘ 2; (2.25) 20 from which it follows that the MA and AR parameters of the random field are related to each other via the recursions b0;0 = a0;0 = 1; bi...

  12. Average transmission probability of a random stack

    E-Print Network [OSTI]

    Yin Lu; Christian Miniatura; Berthold-Georg Englert

    2009-07-31

    The transmission through a stack of identical slabs that are separated by gaps with random widths is usually treated by calculating the average of the logarithm of the transmission probability. We show how to calculate the average of the transmission probability itself with the aid of a recurrence relation and derive analytical upper and lower bounds. The upper bound, when used as an approximation for the transmission probability, is unreasonably good and we conjecture that it is asymptotically exact.

  13. Local semicircle law for random regular graphs

    E-Print Network [OSTI]

    Roland Bauerschmidt; Antti Knowles; Horng-Tzer Yau

    2015-05-26

    We consider random $d$-regular graphs on $N$ vertices, with degree $d$ at least $(\\log N)^4$. We prove that the Green's function of the adjacency matrix and the Stieltjes transform of its empirical spectral measure are well approximated by Wigner's semicircle law, down to the optimal scale given by the typical eigenvalue spacing (up to a logarithmic correction). Aside from well-known consequences for the local eigenvalue distribution, this result implies the complete delocalization of all eigenvectors.

  14. Randomized control of open quantum systems

    E-Print Network [OSTI]

    Lorenza Viola

    2006-01-16

    The problem of open-loop dynamical control of generic open quantum systems is addressed. In particular, I focus on the task of effectively switching off environmental couplings responsible for unwanted decoherence and dissipation effects. After revisiting the standard framework for dynamical decoupling via deterministic controls, I describe a different approach whereby the controller intentionally acquires a random component. An explicit error bound on worst-case performance of stochastic decoupling is presented.

  15. Louisiana Natural Gas Number of Residential Consumers (Number of Elements)

    Gasoline and Diesel Fuel Update (EIA)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustments (Billion Cubic Feet) Wyoming963Residential Consumers (Number of33Cubic Foot)Year Jan

  16. California Natural Gas Number of Residential Consumers (Number of Elements)

    Gasoline and Diesel Fuel Update (EIA)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustments (Billion Cubic Feet) Wyoming963 1.969 1.979Coal4 ArizonaResidential Consumers (Number of Elements)

  17. Nebraska Natural Gas Number of Industrial Consumers (Number of Elements)

    U.S. Energy Information Administration (EIA) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home PageMonthly","10/2015"4,"Ames5 Tables July 1996 Energy Information Administration Office of Coal, Nuclear,Decade Year-03.823,172 3,009165,360Industrial Consumers (Number of

  18. Nebraska Natural Gas Number of Residential Consumers (Number of Elements)

    U.S. Energy Information Administration (EIA) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home PageMonthly","10/2015"4,"Ames5 Tables July 1996 Energy Information Administration Office of Coal, Nuclear,Decade Year-03.823,172 3,009165,360Industrial Consumers (Number

  19. North Dakota Natural Gas Number of Industrial Consumers (Number of

    U.S. Energy Information Administration (EIA) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home PageMonthly","10/2015"4,"Ames5 Tables July 1996 Energy Information Administration Office of Coal, Nuclear,DecadeYear Jan FebElements) Industrial Consumers (Number of

  20. North Dakota Natural Gas Number of Residential Consumers (Number of

    U.S. Energy Information Administration (EIA) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home PageMonthly","10/2015"4,"Ames5 Tables July 1996 Energy Information Administration Office of Coal, Nuclear,DecadeYear Jan FebElements) Industrial Consumers (Number

  1. Random parking, Euclidean functionals, and rubber elasticity

    E-Print Network [OSTI]

    Antoine Gloria; Mathew D. Penrose

    2012-03-06

    We study subadditive functions of the random parking model previously analyzed by the second author. In particular, we consider local functions $S$ of subsets of $\\mathbb{R}^d$ and of point sets that are (almost) subadditive in their first variable. Denoting by $\\xi$ the random parking measure in $\\mathbb{R}^d$, and by $\\xi^R$ the random parking measure in the cube $Q_R=(-R,R)^d$, we show, under some natural assumptions on $S$, that there exists a constant $\\bar{S}\\in \\mathbb{R}$ such that % $$ \\lim_{R\\to +\\infty} \\frac{S(Q_R,\\xi)}{|Q_R|}\\,=\\,\\lim_{R\\to +\\infty}\\frac{S(Q_R,\\xi^R)}{|Q_R|}\\,=\\,\\bar{S} $$ % almost surely. If $\\zeta \\mapsto S(Q_R,\\zeta)$ is the counting measure of $\\zeta$ in $Q_R$, then we retrieve the result by the second author on the existence of the jamming limit. The present work generalizes this result to a wide class of (almost) subadditive functions. In particular, classical Euclidean optimization problems as well as the discrete model for rubber previously studied by Alicandro, Cicalese, and the first author enter this class of functions. In the case of rubber elasticity, this yields an approximation result for the continuous energy density associated with the discrete model at the thermodynamic limit, as well as a generalization to stochastic networks generated on bounded sets.

  2. STOCHASTIC DESIGN AND CONTROL IN RANDOM HETEROGENEOUS MATERIALS

    E-Print Network [OSTI]

    Del Moral , Pierre

    STOCHASTIC DESIGN AND CONTROL IN RANDOM HETEROGENEOUS MATERIALS RAPHAEL STERNFELS AND PHAEDON-STELIOS KOUTSOURELAKIS Abstract. The present paper discusses a sampling framework that enables the optimization concerned with problems relating to random heterogeneous materials where uncertainties arise from

  3. On the mixing time of geographical threshold graphs

    SciTech Connect (OSTI)

    Bradonjic, Milan

    2009-01-01

    In this paper, we study the mixing time of random graphs generated by the geographical threshold graph (GTG) model, a generalization of random geometric graphs (RGG). In a GTG, nodes are distributed in a Euclidean space, and edges are assigned according to a threshold function involving the distance between nodes as well as randomly chosen node weights. The motivation for analyzing this model is that many real networks (e.g., wireless networks, the Internet, etc.) need to be studied by using a 'richer' stochastic model (which in this case includes both a distance between nodes and weights on the nodes). We specifically study the mixing times of random walks on 2-dimensional GTGs near the connectivity threshold. We provide a set of criteria on the distribution of vertex weights that guarantees that the mixing time is {Theta}(n log n).

  4. Asymptotics of finite system Lyapunov exponents for some random matrix ensembles

    E-Print Network [OSTI]

    Peter J. Forrester

    2015-01-23

    For products $P_N$ of $N$ random matrices of size $d \\times d$, there is a natural notion of finite $N$ Lyapunov exponents $\\{\\mu_i\\}_{i=1}^d$. In the case of standard Gaussian random matrices with real, complex or real quaternion elements, and extended to the general variance case for $\\mu_1$, methods known for the computation of $\\lim_{N \\to \\infty} \\langle \\mu_i \\rangle$ are used to compute the large $N$ form of the variances of the exponents. Analogous calculations are performed in the case that the matrices making up $P_N$ are products of sub-blocks of random unitary matrices with Haar measure. Furthermore, we make some remarks relating to the coincidence of the Lyapunov exponents and the stability exponents relating to the eigenvalues of $P_N$.

  5. Monte Carlo Algorithmsa The randomized bipartite perfect matching algorithm is

    E-Print Network [OSTI]

    Lyuu, Yuh-Dauh

    , National Taiwan University Page 461 #12;The Markov Inequalitya Lemma 64 Let x be a random variable taking

  6. Monte Carlo Algorithmsa The randomized bipartite perfect matching algorithm is

    E-Print Network [OSTI]

    Lyuu, Yuh-Dauh

    Markov Inequalitya Lemma 61 Let x be a random variable taking nonnegative integer values. Then for any k

  7. Bayesian compressive sensing for ultrawideband inverse scattering in random media

    E-Print Network [OSTI]

    Fouda, A E

    2014-01-01

    We develop an ultrawideband (UWB) inverse scattering technique for reconstructing continuous random media based on Bayesian compressive sensing. In addition to providing maximum a posteriori estimates of the unknown weights, Bayesian inversion provides estimate of the confidence level of the solution, as well as a systematic approach for optimizing subsequent measurement(s) to maximize information gain. We impose sparsity priors directly on spatial harmonics to exploit the spatial correlation exhibited by continuous media, and solve for their posterior probability density functions efficiently using a fast relevance vector machine. We linearize the problem using the first-order Born approximation which enables us to combine, in a single inversion, measurements from multiple transmitters and ultrawideband frequencies. We extend the method to high-contrast media using the distorted-Born iterative method. We apply time-reversal strategies to adaptively focus the inversion effort onto subdomains of interest, and ...

  8. Renormalized field theory of collapsing directed randomly branched polymers

    E-Print Network [OSTI]

    Hans-Karl Janssen; Frank Wevelsiep; Olaf Stenull

    2009-10-01

    We present a dynamical field theory for directed randomly branched polymers and in particular their collapse transition. We develop a phenomenological model in the form of a stochastic response functional that allows us to address several interesting problems such as the scaling behavior of the swollen phase and the collapse transition. For the swollen phase, we find that by choosing model parameters appropriately, our stochastic functional reduces to the one describing the relaxation dynamics near the Yang-Lee singularity edge. This corroborates that the scaling behavior of swollen branched polymers is governed by the Yang-Lee universality class as has been known for a long time. The main focus of our paper lies on the collapse transition of directed branched polymers. We show to arbitrary order in renormalized perturbation theory with $\\varepsilon$-expansion that this transition belongs to the same universality class as directed percolation.

  9. Spin-Hall-assisted magnetic random access memory

    SciTech Connect (OSTI)

    Brink, A. van den, E-mail: a.v.d.brink@tue.nl; Swagten, H. J. M.; Koopmans, B. [Physics of Nanostructures, Eindhoven University of Technology, 5600 MB Eindhoven (Netherlands)] [Physics of Nanostructures, Eindhoven University of Technology, 5600 MB Eindhoven (Netherlands); Cosemans, S.; Manfrini, M.; Van Roy, W.; Min, T. [imec, Kapeldreef 75, B-3001 Leuven (Belgium)] [imec, Kapeldreef 75, B-3001 Leuven (Belgium); Cornelissen, S.; Vaysset, A. [imec, Kapeldreef 75, B-3001 Leuven (Belgium) [imec, Kapeldreef 75, B-3001 Leuven (Belgium); Departement elektrotechniek (ESAT), KU Leuven, Kasteelpark Arenberg 10, B-3001 Heverlee (Belgium)

    2014-01-06

    We propose a write scheme for perpendicular spin-transfer torque magnetoresistive random-access memory that significantly reduces the required tunnel current density and write energy. A sub-nanosecond in-plane polarized spin current pulse is generated using the spin-Hall effect, disturbing the stable magnetic state. Subsequent switching using out-of-plane polarized spin current becomes highly efficient. Through evaluation of the Landau-Lifshitz-Gilbert equation, we quantitatively assess the viability of this write scheme for a wide range of system parameters. A typical example shows an eight-fold reduction in tunnel current density, corresponding to a fifty-fold reduction in write energy, while maintaining a 1?ns write time.

  10. Theory of Large Dimensional Random Matrices for Engineers

    E-Print Network [OSTI]

    matrix theory in wireless communication theory, interest in the study of random matrices began of asymptotic random matrix theory, has emerged in the communications and information theory literature of the statistics of random matrices arising in wireless communications. The emphasis will be on asymptotic

  11. Stretched Polymers in Random Environment Dmitry Ioffe and Yvan Velenik

    E-Print Network [OSTI]

    Velenik, Yvan

    Stretched Polymers in Random Environment Dmitry Ioffe and Yvan Velenik Abstract We survey recent results and open questions on the ballistic phase of stretched polymers in both annealed and quenched Introduction Stretched polymers or drifted random walks in random potentials could be consid- ered either

  12. Quantum randomness extraction for various levels of characterization of the devices

    E-Print Network [OSTI]

    Yun Zhi Law; Le Phuc Thinh; Jean-Daniel Bancal; Valerio Scarani

    2014-10-15

    The amount of intrinsic randomness that can be extracted from measurement on quantum systems depends on several factors: notably, the power given to the adversary and the level of characterization of the devices of the authorized partners. After presenting a systematic introduction to these notions, in this paper we work in the class of least adversarial power, which is relevant for assessing setups operated by trusted experimentalists, and compare three levels of characterization of the devices. Many recent studies have focused on the so-called "device-independent" level, in which a lower bound on the amount of intrinsic randomness can be certified without any characterization. The other extreme is the case when all the devices are fully characterized: this "tomographic" level has been known for a long time. We present for this case a systematic and efficient approach to quantifying the amount of intrinsic randomness, and show that setups involving ancillas (POVMs, pointer measurements) may not be interesting here, insofar as one may extract randomness from the ancilla rather than from the system under study. Finally, we study how much randomness can be obtained in presence of an intermediate level of characterization related to the task of "steering", in which Bob's device is fully characterized while Alice's is a black box. We obtain our results here by adapting the NPA hierarchy of semidefinite programs to the steering scenario.

  13. A Proposed Exact Integer Value for Avogadro's Number

    E-Print Network [OSTI]

    Ronald F. Fox; Theodore P. Hill

    2007-04-28

    An exact value for Avodagro's number, namely NA* = (84446888)^3, is proposed. The number 84446888 represents the side length of a cube of atoms whose volume is closest, among all integral side lengths, to the current official NIST value of Avogadro's number. This value NA* is nearly dead center of the estimated range for the value of Avogadro's number, and is within the official standard level of uncertainty. Adoption of this value as the fixed value for NA would eliminate the current time-dependent definition of Avogadro's number, which depends on the definition of kilogram via an unstable physical artifact. It would also eliminate the need for the kilogram artifact altogether, since then, by definition, a kilogram would be exactly 1000/12 the mass of NA* atoms of carbon-12.

  14. The Fermat and Mersenne Numbers 

    E-Print Network [OSTI]

    Nowlin, W. D.

    1960-01-01

    . (Throughout this thesis, F will always denote a Feraat nmaber and M a Mersenne nuuber. ) The problea of deternining p which of the Fernat and Mersenne nmabers are prius has concerned uany matheuaticians during the last two centuries. This research has... or a Fermat, number. Next? Froth~a theorem, of which Pepin's test is a special case, is stated and proved. In the last section the theory of recurring series is used to establish primality tests of the Lucas type for both the Fermat and Mersenne...

  15. The thermodynamics of time

    E-Print Network [OSTI]

    Dries Sels; Michiel Wouters

    2015-01-22

    The problem of time is a deep paradox in our physical description of the world. According to Aristotle's relational theory, time is a measure of change and does not exist on its own. In contrast, quantum mechanics, just like Newtonian mechanics, is equipped with a master clock that dictates the evolution of a system. This clock is infinitely precise and tacitly supplied free of charge from outside physics. Not only does this absolute time make it notoriously difficult to make a consistent theory of quantum gravity, it is also the underlying problem in establishing the second law. Indeed, contrary to our experience, the Wheeler-deWitt equation --a canonical quantization of general relativity-- predicts a static universe. Similarly, when simply concerned with the dynamics of a closed quantum system, there is no second law because the Von Neumann entropy is invariant under unitary transformations. Here we are mainly concerned with the latter problem and we show that it can be resolved by attributing a minimal amount of resources to the measurement of time. Although there is an absolute time in quantum mechanics, an observer can only establish a time by measuring a clock. For a local measurement, the minimal entropy production is equal to the number of ticks. This lower bound is attained by a black hole.

  16. A Linear-Time Approach for Static Timing Analysis Covering All Process Corners

    E-Print Network [OSTI]

    Najm, Farid N.

    A Linear-Time Approach for Static Timing Analysis Covering All Process Corners Sari Onaissi into the timing analysis of a circuit. With the increase in the number of interesting process vari- ables process variations lead to circuit timing variability and a corresponding timing yield loss. Traditional

  17. DRAFT CRUISE REPORT Cruise Number: DY0807

    E-Print Network [OSTI]

    Neuston (Neu) 68 Deployment of satellite buoy (SatBuoy) 3 Samples Collected Tows Number Number of larvae of buoy or mooring (Deploy) 3 3 Stimulated fluorescence collected during CTD casts (Fluor) 18 Number

  18. A random walk approach to anomalous particle and energy transport

    E-Print Network [OSTI]

    H. Isliker

    2007-10-26

    The combined Continuous Time Random Walk (CTRW) in position and momentum space is introduced, in the form of two coupled integral equations that describe the evolution of the probability distribution for finding a particle at a certain position and with a certain momentum as a function of time. The integral equations are solved numerically with a pseudospectral method that is based on the expansion of the unknown functions in terms of Chebyshev polynomials. In parallel, Monte-Carlo simulation are performed. Through the inclusion of momentum space, the combined CTRW is able to yield results on density and temperature profile evolution, on particle and heat fluxes and diffusivities, and on kinetic energy distributions. Depending on the choice of the probability distributions of the particle displacements in position and momentum space, the combined CTRW is able to model phenomena of anomalous transport in position as well as in momentum (or energy or velocity) space. An application is made to a toroidally confined plasma that undergoes off-center injection of cold plasma (off-axis fueling), using two variants of the model, the mixed model and the critical gradient model. The phenomenon of profile stiffness is addressed, both for the density and for the temperature profile, respectively, and the particle and energy confinement times are determined. The analysis of the particle and heat fluxes shows that the dynamics realized in the combined CTRW is incompatible with the classical approach of Fick's or Fourier's law for particle and heat transport, respectively.

  19. Low-temperature random matrix theory at the soft edge

    SciTech Connect (OSTI)

    Edelman, Alan; Persson, Per-Olof; Sutton, Brian D.

    2014-06-15

    “Low temperature” random matrix theory is the study of random eigenvalues as energy is removed. In standard notation, ? is identified with inverse temperature, and low temperatures are achieved through the limit ? ? ?. In this paper, we derive statistics for low-temperature random matrices at the “soft edge,” which describes the extreme eigenvalues for many random matrix distributions. Specifically, new asymptotics are found for the expected value and standard deviation of the general-? Tracy-Widom distribution. The new techniques utilize beta ensembles, stochastic differential operators, and Riccati diffusions. The asymptotics fit known high-temperature statistics curiously well and contribute to the larger program of general-? random matrix theory.

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

    SciTech Connect (OSTI)

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

    2013-07-01

    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.

  1. Cover art: issues in the metric-guided and metric-less placement of random and stochastic template banks

    E-Print Network [OSTI]

    Gian Mario Manca; Michele Vallisneri

    2010-01-14

    The efficient placement of signal templates in source-parameter space is a crucial requisite for exhaustive matched-filtering searches of modeled gravitational-wave sources. Unfortunately, the current placement algorithms based on regular parameter-space meshes are difficult to generalize beyond simple signal models with few parameters. Various authors have suggested that a general, flexible, yet efficient alternative can be found in randomized placement strategies such as random placement and stochastic placement, which enhances random placement by selectively rejecting templates that are too close to others. In this article we explore several theoretical and practical issues in randomized placement: the size and performance of the resulting template banks; the effects of parameter-space boundaries; the use of quasi-random (self avoiding) number sequences; most important, the implementation of these algorithms in curved signal manifolds with and without the use of a Riemannian signal metric, which may be difficult to obtain. Specifically, we show how the metric can be replaced with a discrete triangulation-based representation of local geometry. We argue that the broad class of randomized placement algorithms offers a promising answer to many search problems, but that the specific choice of a scheme and its implementation details will still need to be fine-tuned separately for each problem.

  2. Effects of a random spatial variation of the plasma density on the mode conversion in cold, unmagnetized, and stratified plasmas

    SciTech Connect (OSTI)

    Jung Yu, Dae; Kim, Kihong

    2013-12-15

    We study the effects of a random spatial variation of the plasma density on the mode conversion of electromagnetic waves into electrostatic oscillations in cold, unmagnetized, and stratified plasmas. Using the invariant imbedding method, we calculate precisely the electromagnetic field distribution and the mode conversion coefficient, which is defined to be the fraction of the incident wave power converted into electrostatic oscillations, for the configuration where a numerically generated random density variation is added to the background linear density profile. We repeat similar calculations for a large number of random configurations and take an average of the results. We obtain a peculiar nonmonotonic dependence of the mode conversion coefficient on the strength of randomness. As the disorder increases from zero, the maximum value of the mode conversion coefficient decreases initially, then increases to a maximum, and finally decreases towards zero. The range of the incident angle in which mode conversion occurs increases monotonically as the disorder increases. We present numerical results suggesting that the decrease of mode conversion mainly results from the increased reflection due to the Anderson localization effect originating from disorder, whereas the increase of mode conversion of the intermediate disorder regime comes from the appearance of many resonance points and the enhanced tunneling between the resonance points and the cutoff point. We also find a very large local enhancement of the magnetic field intensity for particular random configurations. In order to obtain high mode conversion efficiency, it is desirable to restrict the randomness close to the resonance region.

  3. Stochastic evolution equations with random generators

    E-Print Network [OSTI]

    Leon, Jorge A.; Nualart, David

    1998-05-01

    maximal inequality for the Skorohod integral deduced from the It ˆ o’s formula for this anticipating stochastic integral. 1. Introduction. In this paper we study nonlinear stochastic evolution equations of the form X t = ? + ? t 0 #3;A#3;s#4;X s +F#3;s#7;X.... The functions F#3;s#7;?#7; x#4; and B#3;s#7;?#7; x#4; are predictable processes satisfying suitable Lipschitz–type conditions and taking values in H and L 2 #3;U#7;H#4;, respectively. We will assume that A#3;s#7;?#4; is a random family of unbounded operators...

  4. Emergent geometry from random multitrace matrix models

    E-Print Network [OSTI]

    B. Ydri; A. Rouag; K. Ramda

    2015-09-11

    A novel scenario for the emergence of geometry in random multitrace matrix models of a single hermitian matrix $M$ with unitary $U(N) $ invariance, i.e. without a kinetic term, is presented. In particular, the dimension of the emergent geometry is determined from the critical exponents of the disorder-to-uniform-ordered transition whereas the metric is determined from the Wigner semicircle law behavior of the eigenvalues distribution of the matrix $M$. If the uniform ordered phase is not sustained in the phase diagram then there is no emergent geometry in the multitrace matrix model.

  5. Relativistic Random Phase Approximation At Finite Temperature

    SciTech Connect (OSTI)

    Niu, Y. F.; Paar, N.; Vretenar, D.; Meng, J.

    2009-08-26

    The fully self-consistent finite temperature relativistic random phase approximation (FTRRPA) has been established in the single-nucleon basis of the temperature dependent Dirac-Hartree model (FTDH) based on effective Lagrangian with density dependent meson-nucleon couplings. Illustrative calculations in the FTRRPA framework show the evolution of multipole responses of {sup 132}Sn with temperature. With increased temperature, in both monopole and dipole strength distributions additional transitions appear in the low energy region due to the new opened particle-particle and hole-hole transition channels.

  6. Open quantum systems and Random Matrix Theory

    E-Print Network [OSTI]

    Declan Mulhall

    2015-01-09

    A simple model for open quantum systems is analyzed with Random Matrix Theory. The system is coupled to the continuum in a minimal way. In this paper we see the effect of opening the system on the level statistics, in particular the $\\Delta_3(L)$ statistic, width distribution and level spacing are examined as a function of the strength of this coupling. A super-radiant transition is observed, and it is seen that as it is formed, the level spacing and $\\Delta_3(L)$ statistic exhibit the signatures of missed levels.

  7. Chaotic motion of three-body problem : an origin of macroscopic randomness of the universe

    E-Print Network [OSTI]

    Shijun Liao

    2013-04-08

    The famous three-body problem is investigated by means of a numerical approach with negligible numerical noises in a long enough time interval, namely the Clean Numerical Simulation (CNS). From physical viewpoints, position of any bodies contains inherent micro-level uncertainty. The evaluations of such kind of inherent micro-level uncertainty are accurately simulated by means of the CNS. Our reliable, very accurate CNS results indicate that the inherent micro-level uncertainty of position of a star/planet might transfer into macroscopic randomness. Thus, the inherent micro-level uncertainty of a body might be an origin of macroscopic randomness of the universe. In addition, from physical viewpoints, orbits of some three-body systems at large time are inherently random, and thus it has no physical meanings to talk about the accurate long-term prediction of the chaotic orbits. Note that such kind of uncertainty and randomness has nothing to do with the ability of human being. All of these might enrich our knowledge and deepen our understandings about not only the three-body problem but also chaos.

  8. Statistical Properties of the T-exponential of Isotropically Distributed Random Matrices

    E-Print Network [OSTI]

    Anton S. Il'yn; Valeria A. Sirota; Kirill P. Zybin

    2015-06-05

    A functional method for calculating averages of the time-ordered exponential of a continuous isotropic random $N\\times N$ matrix process is presented. The process is not assumed to be Gaussian. In particular, the Lyapunov exponents and higher correlation functions of the T-exponent are derived from the statistical properties of the process. The approach may be of use in a wide range of physical problems. For example, in theory of turbulence the account of non-gaussian statistics is very important since the non-Gaussian behavior is responsible for the time asymmetry of the energy flow.

  9. An objective change point analysis of landfalling historical Atlantic hurricane numbers

    E-Print Network [OSTI]

    Jewson, S; Jewson, Stephen; Penzer, Jeremy

    2006-01-01

    In previous work we have analysed the Atlantic basin hurricane number time-series to identify decadal time-scale change points. We now repeat the analysis but for US landfalling hurricanes. The results are very different.

  10. Space-time diamonds

    E-Print Network [OSTI]

    Daiqin Su; T. C. Ralph

    2015-07-02

    We show that the particle number distribution of diamond modes, modes that are localised in a finite space-time region, are thermal for the Minkowski vacuum state of a massless scalar field, an analogue to the Unruh effect. The temperature of the diamond is inversely proportional to its size. An inertial observer can detect this thermal radiation by coupling to the diamond modes using an appropriate energy scaled detector. We further investigate the correlations between various diamonds and find that entanglement between adjacent diamonds dominates.

  11. Passive tracer in a slowly decorrelating random flow with a large mean

    E-Print Network [OSTI]

    Tomasz Komorowski; Lenya Ryzhik

    2006-07-25

    We consider the movement of a particle advected by a random flow of the form $\\vv+\\delta \\bF(\\vx)$, with $\\vv\\in\\R^d$ a constant drift, $\\bF(\\vx)$ -- the fluctuation -- given by a zero mean, stationary random field and $\\delta\\ll 1$ so that the drift dominates over the fluctuation. The two-point correlation matrix $\\bR(\\vx)$ of the random field decays as $|\\vx|^{2\\alpha-2}$, as $|\\vx|\\to+\\infty$ with $\\alpha<1$. The Kubo formula for the effective diffusion coefficient obtained in \\cite{kp79} for rapidly decorrelating fields diverges when $1/2\\le\\alpha<1$. We show formally that on the time scale $\\delta^{-1/\\alpha}$ the deviation of the trajectory from its mean $\\by(t)=\\vx(t)-\\vv t$ converges to a fractional Brownian motion $B_\\alpha(t)$ in this range of the exponent $\\alpha$. We also prove rigorously upper and lower bounds which show that $\\E[|\\by(t)|^2]$ converges to zero for times $t\\ll\\delta^{-1/\\alpha}$ and to infinity on time scales $t\\gg \\delta^{-1/\\alpha}$ as $\\delta\\to 0$ when $\\alpha\\in(1/2,1)$. On the other hand, when $\\alpha<1/2$ non-trivial behavior is observed on the time-scale $O(\\delta^{-2})$.

  12. Random unitary maps for quantum state reconstruction

    SciTech Connect (OSTI)

    Merkel, Seth T. [Institute for Quantum Computing, Waterloo, Ontario N2L 3G1 (Canada); Riofrio, Carlos A.; Deutsch, Ivan H. [Center for Quantum Information and Control (CQuIC), Department of Physics and Astronomy, University of New Mexico, Albuquerque, New Mexico, 87131 (United States); Flammia, Steven T. [Perimeter Institute for Theoretical Physics, Waterloo, Ontario N2L 2Y5 (Canada); Kavli Institute for Theoretical Physics, University of California, Santa Barbara, California 93106 (United States)

    2010-03-15

    We study the possibility of performing quantum state reconstruction from a measurement record that is obtained as a sequence of expectation values of a Hermitian operator evolving under repeated application of a single random unitary map, U{sub 0}. We show that while this single-parameter orbit in operator space is not informationally complete, it can be used to yield surprisingly high-fidelity reconstruction. For a d-dimensional Hilbert space with the initial observable in su(d), the measurement record lacks information about a matrix subspace of dimension {>=}d-2 out of the total dimension d{sup 2}-1. We determine the conditions on U{sub 0} such that the bound is saturated, and show they are achieved by almost all pseudorandom unitary matrices. When we further impose the constraint that the physical density matrix must be positive, we obtain even higher fidelity than that predicted from the missing subspace. With prior knowledge that the state is pure, the reconstruction will be perfect (in the limit of vanishing noise) and for arbitrary mixed states, the fidelity is over 0.96, even for small d, and reaching F>0.99 for d>9. We also study the implementation of this protocol based on the relationship between random matrices and quantum chaos. We show that the Floquet operator of the quantum kicked top provides a means of generating the required type of measurement record, with implications on the relationship between quantum chaos and information gain.

  13. Multidimensional Random Polymers : A Renewal Approach

    E-Print Network [OSTI]

    Dmitry Ioffe

    2014-11-30

    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 $d=1,2$.

  14. Ramsey numbers of sparse hypergraphs David Conlon

    E-Print Network [OSTI]

    Fox, Jacob

    Ramsey numbers of sparse hypergraphs David Conlon Jacob Fox Benny Sudakov Abstract We give a short proof that any k-uniform hypergraph H on n vertices with bounded degree has Ramsey number at most c(, k on the Ramsey number of hypergraphs with at most m edges. 1 Introduction For a graph H, the Ramsey number r

  15. Stressed Cooper pairing in QCD at high isospin density: effective Lagrangian and random matrix theory

    E-Print Network [OSTI]

    Takuya Kanazawa; Tilo Wettig

    2014-09-28

    We generalize QCD at asymptotically large isospin chemical potential to an arbitrary even number of flavors. We also allow for small quark chemical potentials, which stress the coincident Fermi surfaces of the paired quarks and lead to a sign problem in Monte Carlo simulations. We derive the corresponding low-energy effective theory in both $p$- and $\\epsilon$-expansion and quantify the severity of the sign problem. We construct the random matrix theory describing our physical situation and show that it can be mapped to a known random matrix theory at low baryon density so that new insights can be gained without additional calculations. In particular, we explain the Silver Blaze phenomenon at high isospin density. We also introduce stressed singular values of the Dirac operator and relate them to the pionic condensate. Finally we comment on extensions of our work to two-color QCD.

  16. Department for Analysis and Computational Number Theory Additive functions and number systems

    E-Print Network [OSTI]

    Department for Analysis and Computational Number Theory Additive functions and number systems systems April 7, 2010 1 / 35 #12;Department for Analysis and Computational Number Theory Outline Number and Computational Number Theory Number systems Let R be an integral domain, b R, and N = {n1, . . . , nm} R

  17. Instability of High Mach Number Poiseuille (Channel) Flow: Linear Analysis and Direct Numerical Simulations 

    E-Print Network [OSTI]

    Xie, Zhimin

    2014-08-06

    is examined. Grid resolution and time-step convergence studies are performed over the range of Mach numbers of interest. The next study establishes the stability characteristics at very high and very low Mach number limits. While stability at low Mach number...

  18. A Version Numbering Scheme with a Useful Lexicographical Order

    E-Print Network [OSTI]

    Keller, Arthur M.

    A Version Numbering Scheme with a Useful Lexicographical Order Arthur M. Kellery Je rey D. Ullmanz Engineering Database. This e ort is funded in part by NSF grant IRI 91 16646. yArthur Keller's e-mail address records can be obtained in little more than the time it takes to access data of this bulk. Our primary

  19. POLICY NUMBER 2007-02 March 27, 2007

    E-Print Network [OSTI]

    POLICY NUMBER 2007-02 March 27, 2007 POLICY: Internal Investigation Policy ­ Office of Audit by federal, state, and local laws, regulations and University policy. The UCHC Compliance Office strives to prevent, detect and, in a timely manner, correct violations of law or policy, which may result from

  20. Dynamics of Random Boolean Networks with Non-Constant Number of Parents and Asynchrony Generated by Stochastic Processes

    E-Print Network [OSTI]

    Matache, Dora

    to generate consecutive states of the network for both the real system and the model. We use Poisson by Stochastic Processes Xutao Deng Advisor: Dora Matache Department of Computer Science University of Nebraska nodes, which may vary from one node to another. This is an extension of a model studied by Matache

  1. Fresh look at randomly branched polymers

    E-Print Network [OSTI]

    Hans-Karl Janssen; Olaf Stenull

    2009-11-09

    We develop a new, dynamical field theory of isotropic randomly branched polymers, and we use this model in conjunction with the renormalization group (RG) to study several prominent problems in the physics of these polymers. Our model provides an alternative vantage point to understand the swollen phase via dimensional reduction. We reveal a hidden Becchi-Rouet-Stora (BRS) symmetry of the model that describes the collapse ($\\theta$-)transition to compact polymer-conformations, and calculate the critical exponents to 2-loop order. It turns out that the long-standing 1-loop results for these exponents are not entirely correct. A runaway of the RG flow indicates that the so-called $\\theta^\\prime$-transition could be a fluctuation induced first order transition.

  2. COMPUTING THE TOP BETTI NUMBERS OF SEMI-ALGEBRAIC SETS DEFINED BY QUADRATIC

    E-Print Network [OSTI]

    Basu, Saugata

    COMPUTING THE TOP BETTI NUMBERS OF SEMI-ALGEBRAIC SETS DEFINED BY QUADRATIC INEQUALITIES IN POLYNOMIAL TIME SAUGATA BASU Abstract. For any > 0, we present an algorithm which takes as input a semi-algebraic the top Betti numbers of S, bk-1(S), . . . , bk- (S), in polynomial time. The complexity of the algorithm

  3. SACI: Statistical Static Timing Analysis of Coupled Interconnects

    E-Print Network [OSTI]

    Pedram, Massoud

    in the circuit timing that stem from various sources of variations. However, static timing analysis (STA crosstalk effects in these circuits. As a result, crosstalk analysis and management have been classified line as a linear function of random variables and then use these r.v.'s to compute the circuit mo

  4. Dispatch R427 Time perception: Brain time or event time?

    E-Print Network [OSTI]

    Johnston, Alan

    Dispatch R427 Time perception: Brain time or event time? Alan Johnston* and Shin'ya Nishida Recent experiments show that synchronous events can appear to an observer to occur at different times. Neural processing time delays are offered as an explanation of these temporal illusions, but equating perceived time

  5. Distribution of occupation numbers in finite Fermi systems and role of interaction in chaos and thermalization

    SciTech Connect (OSTI)

    Flambaum, V.V.; Izrailev, F.M. [School of Physics, University of New South Wales, Sydney 2052 (Australia)] [School of Physics, University of New South Wales, Sydney 2052 (Australia)

    1997-01-01

    A method is developed for calculation of single-particle occupation numbers in finite Fermi systems of interacting particles. It is more accurate than the canonical distribution method and gives the Fermi-Dirac distribution in the limit of large number of particles. It is shown that statistical effects of the interaction are absorbed by an increase of the effective temperature. Criteria for quantum chaos and statistical equilibrium are considered. All results are confirmed by numerical experiments in the two-body random interaction model. {copyright} {ital 1997} {ital The American Physical Society}

  6. Prime number generation and factor elimination

    E-Print Network [OSTI]

    Vineet Kumar

    2014-10-06

    We have presented a multivariate polynomial function termed as factor elimination function,by which, we can generate prime numbers. This function's mapping behavior can explain the irregularities in the occurrence of prime numbers on the number line. Generally the different categories of prime numbers found till date, satisfy the form of this function. We present some absolute and probabilistic conditions for the primality of the number generated by this method. This function is capable of leading to highly efficient algorithms for generating prime numbers.

  7. Low energy properties of the random displacement model

    E-Print Network [OSTI]

    Jeff Baker; Michael Loss; Günter Stolz

    2008-08-05

    We study low-energy properties of the random displacement model, a random Schr\\"odinger operator describing an electron in a randomly deformed lattice. All periodic displacement configurations which minimize the bottom of the spectrum are characterized. While this configuration is essentially unique for dimension greater than one, there are infinitely many different minimizing configurations in the one-dimensional case. The latter leads to unusual low energy asymptotics for the integrated density of states of the one-dimensional random displacement model. For symmetric Bernoulli-distributed displacements it has a $1/\\log^2$-singularity at the bottom of the spectrum. In particular, it is not H\\"older-continuous.

  8. Embedding quantum and random optics in a larger field theory

    E-Print Network [OSTI]

    Peter Morgan

    2008-06-09

    Introducing creation and annihilation operators for negative frequency components extends the algebra of smeared local observables of quantum optics to include an associated classical random field optics.

  9. Random Symmetry Breaking and Freezing in Chaotic Networks

    E-Print Network [OSTI]

    Y. Peleg; W. Kinzel; I. Kanter

    2012-04-02

    Parameter space of a driven damped oscillator in a double well potential presents either a chaotic trajectory with sign oscillating amplitude or a non-chaotic trajectory with a fixed sign amplitude. A network of such delay coupled damped oscillators is shown to present chaotic dynamics while the amplitude sign of each damped oscillator is randomly frozen. This phenomenon of random broken global symmetry of the network simultaneously with random freezing of each degree of freedom is accompanied by the existence of exponentially many randomly frozen chaotic attractors with the ize of the network. Results are exemplified by a network of modified Duffing oscillators with infinite ange pseudo-inverse delayed interactions.

  10. 18.440 Probability and Random Variables, Spring 2011

    E-Print Network [OSTI]

    Sheffield, Scott

    This course introduces students to probability and random variables. Topics include distribution functions, binomial, geometric, hypergeometric, and Poisson distributions. The other topics covered are uniform, exponential, ...

  11. 18.440 Probability and Random Variables, Spring 2009

    E-Print Network [OSTI]

    Dudley, Richard

    This course introduces students to probability and random variables. Topics include distribution functions, binomial, geometric, hypergeometric, and Poisson distributions. The other topics covered are uniform, exponential, ...

  12. Stress Tensor for Quantized Random Field and Wave Function Collapse

    E-Print Network [OSTI]

    Philip Pearle

    2008-08-13

    The continuous spontaneous localization (CSL) theory of dynamical wave function collapse is an experimentally testable alternative to non-relativistic quantum mechanics. In it, collapse occurs because particles interact with a classical random field. However, particles gain energy from this field, i.e., particle energy is not conserved. Recently, it has been shown how to construct a theory dubbed "completely quantized collapse" (CQC) which is predictively equivalent to CSL. In CQC, a quantized random field is introduced, and CSL's classical random field becomes its eigenvalue. In CQC, energy is conserved, which allows one to understand that energy is conserved in CSL, as the particle's energy gain is compensated by the random field's energy loss. Since the random field has energy, it should have gravitational consequences. For that, one needs to know the random field's energy density. In this paper, it is shown how to construct a symmetric, conserved, energy-momentum-stress-density tensor associated with the quantized random field, even though this field obeys no dynamical equation and has no Lagrangian. Then, three examples are given involving the random field's energy density. One considers interacting particles, the second treats a "cosmological" particle creation model, the third involves the gravity of the random field.

  13. Listening to the noise: random fluctuations reveal gene network...

    Office of Scientific and Technical Information (OSTI)

    Title: Listening to the noise: random fluctuations reveal gene network parameters The cellular environment is abuzz with noise. The origin of this noise is attributed to the...

  14. Kernel Carpentry for Online Regression using Randomly Varying Coefficient Model 

    E-Print Network [OSTI]

    Edakunni, Narayanan U.; Schaal, Stefan; Vijayakumar, Sethu

    2006-01-01

    We present a Bayesian formulation of locally weighted learning (LWL) using the novel concept of a randomly varying coefficient model. Based on this

  15. Time Management Managing Time and Tasks

    E-Print Network [OSTI]

    Kunkle, Tom

    Time Management Managing Time and Tasks What is time management? Time can't be managed ­ but you can manage the amount of time you use each day for fun, work, rest, and time spent with others. Why is time management important? You have responsibilities to yourself, to your family and friends, to your

  16. Adsorption of symmetric random copolymer onto symmetric random surface: the annealed case

    E-Print Network [OSTI]

    A. A. Polotsky

    2015-06-12

    Adsorption of a symmetric (AB) random copolymer (RC) onto a symmetric (ab) random heterogeneous surface (RS) is studied in the annealed approximation by using a two-dimensional partially directed walk model of the polymer. We show that in the symmetric case, the expected a posteriori compositions of the RC and the RS have correct values (corresponding to their a priori probabilities) and do not change with the temperature, whereas second moments of monomers and sites distributions in the RC and RS change. This indicates that monomers and sites do not interconvert but only rearrange in order to provide better matching between them and, as a result, a stronger adsorption of the RC on the RS. However, any violation of the system symmetry shifts equilibrium towards the major component and/or more favorable contacts and leads to interconversion of monomers and sites.

  17. Time parallel gravitational collapse simulation

    E-Print Network [OSTI]

    Kreienbuehl, Andreas; Ruprecht, Daniel; Krause, Rolf

    2015-01-01

    This article demonstrates the applicability of the parallel-in-time method Parareal to the numerical solution of the Einstein gravity equations for the spherical collapse of a massless scalar field. To account for the shrinking of the spatial domain in time, a tailored load balancing scheme is proposed and compared to load balancing based on number of time steps alone. The performance of Parareal is studied for both the sub-critical and black hole case; our experiments show that Parareal generates substantial speedup and, in the super-critical regime, can also reproduce the black hole mass scaling law.

  18. Small Ramsey Numbers Stanislaw P. Radziszowski

    E-Print Network [OSTI]

    Radziszowski, Stanislaw P.

    Small Ramsey Numbers Stanislaw P. Radziszowski Department of Computer Science Rochester Institute Ramsey numbers, where the avoided graphs are complete or complete without one edge. Many results per behavior of Ramsey numbers, but rather we concentrate on their specific values. Mathematical Reviews

  19. Ramsey Numbers Involving Cycles Stanislaw P. Radziszowski

    E-Print Network [OSTI]

    Radziszowski, Stanislaw P.

    Ramsey Numbers Involving Cycles Stanislaw P. Radziszowski Department of Computer Science Rochester and data on Ramsey numbers involving cycles. This survey is based on the author's 2009 revi- sion #12 of the Dynamic Survey DS1, "Small Ramsey Numbers", at the Electronic Journal of Combinatorics. Table of Contents

  20. SHARP THRESHOLDS FOR HYPERGRAPH REGRESSIVE RAMSEY NUMBERS

    E-Print Network [OSTI]

    Lee, Gyesik

    SHARP THRESHOLDS FOR HYPERGRAPH REGRESSIVE RAMSEY NUMBERS LORENZO CARLUCCI, GYESIK LEE, AND ANDREAS WEIERMANN Abstract. The f-regressive Ramsey number Rreg f (d, n) is the minimum N such that every colouring regressive Ramsey numbers as defined by Kanamori and McAloon. In this paper we classifiy the growth

  1. Motivation Examples Star Avoiding Ramsey Numbers

    E-Print Network [OSTI]

    Isaak, Garth

    Motivation Examples Star Avoiding Ramsey Numbers Jonelle Hook, Garth Isaak Department and Cryptography Jonelle Hook, Garth Isaak Star Avoiding Ramsey Numbers #12;Motivation Examples Graph Ramsey-coloring of K13 has a red C5 or a blue K4. Jonelle Hook, Garth Isaak Star Avoiding Ramsey Numbers #12

  2. Diagonal Ramsey Numbers in Multipartite Graphs

    E-Print Network [OSTI]

    van Vuuren, Jan H.

    Diagonal Ramsey Numbers in Multipartite Graphs AP Burger , PJP Grobler , EH Stipp & JH van Vuuren September 17, 2003 Abstract The notion of a graph theoretic Ramsey number is generalised by assuming definition. Some small multipartite Ramsey numbers are found, while upper and lower bounds are established

  3. Diagonal Ramsey Numbers in Multipartite Graphs

    E-Print Network [OSTI]

    van Vuuren, Jan H.

    Diagonal Ramsey Numbers in Multipartite Graphs AP Burger + , PJP Grobler # , EH Stipp # & JH van Vuuren # September 17, 2003 Abstract The notion of a graph theoretic Ramsey number is generalised as in the classical definition. Some small multipartite Ramsey numbers are found, while upper and lower bounds

  4. Company number 5857955 Wellcome Trust Finance plc

    E-Print Network [OSTI]

    Rambaut, Andrew

    Company number 5857955 Wellcome Trust Finance plc Annual Report and Financial Statements Year ended 30 September 2014 #12;Company number 5857955 Wellcome Trust Finance plc Contents Page Strategic number 58579551 Wellcome Trust Finance plc Strategic Report For the year ended 30 September 2014

  5. KIAS SEOUL, February 2004 Transcendental Number Theory

    E-Print Network [OSTI]

    Waldschmidt, Michel

    ) ­ Introductio in Analysin Infinitorum. Suggests the transcendence of log 1/ log 2 when this number is irrational in Analysin Infinitorum. Suggests the transcendence of log 1/ log 2 when this number is irrational (for this number is irrational (for algebraic 1 and 2). http://www.math.jussieu.fr/miw/ 14 #12;Euler (1748

  6. Number Theory I: Tools and Diophantine Equations

    E-Print Network [OSTI]

    Cohen, Henri

    covered by two other books of the author [Coh0] and [Coh1]. The central (although not unique) theme in integers, rational numbers, or more generally in algebraic numbers. This theme is in particular the central of the reader that he or she is familiar with the standard basic theory of number fields, up to and including

  7. Clar number of catacondensed benzenoid hydrocarbons

    E-Print Network [OSTI]

    Klavzar, Sandi

    Clar number of catacondensed benzenoid hydrocarbons Sandi KlavŸzar a,# , Petra Ÿ Zigert a , Ivan hydrocarbon: CL is equal to the minimum number of straight lines required to intersect all hexagons theory; Clar formula; Clar number; Resonance graph; Benzenoid hydrocarbons 1. Introduction Within

  8. Spin transitions in time-dependent regular and random magnetic fields 

    E-Print Network [OSTI]

    Pokrovsky, Valery L.; Sinitsyn, NA.

    2004-01-01

    -Zener solution a5exp~2pg2!, b52 A2p expS2 pg22 1 ip4 D gG~2ig2! . ~7! When g varies from 0 to ` , the modulus uau changes from 1 to 0 and the argument of the Jacobi polynomial in Eq. ~6! 2 2 2u A !a !b 2 . 6 ua 2 g , g . . . g the Bloch tensors... gz . ~25! Solving equation for g6 , we find g6~ t !5g6~2`!expS7ib? zt22 7iE 2` t hz~ t8!dt8D ~26! 1~ i/A2 !E 2` t expF7ib? z~ t22t82!2 7iE t8 t hz~ t9!dt9Gh6~ t8!gz~ t8!dt8. ~27! Let us first consider the case of complete initial...

  9. Continuous time random walk analysis of solute transport in fractured porous media

    E-Print Network [OSTI]

    Cortis, Andrea

    2008-01-01

    using breakthrough curves (BTC, see Figure 4) obtained atthe matrix pore system. The dashed BTC indicates the localmodel domain, L=50 m. The four BTC locations shown in Figure

  10. Upscaling solute transport in naturally fractured porous media with the continuous time random walk method

    E-Print Network [OSTI]

    Geiger, S.

    2012-01-01

    a backwards prediction for the BTC at ? = 0.25 (red solidCalibration of the ?(t) on the BTC at ? = 0.25 (not shown)to calibrate the ?(t) on a BTC at ? = 0.1. For other less

  11. Uniform approximation of the CIR process via exact simulation at random times

    E-Print Network [OSTI]

    Schoenmakers, John

    was partially supported through Research Center Matheon "Mathematics for Key Technologies" in Berlin. Ural Federal University, Lenin Str. 51, 620083 Ekaterinburg, Russia; email: Grigori

  12. Random polynomial-time attacks and Dolev-Yao models Mathieu Baudet

    E-Print Network [OSTI]

    Doyen, Laurent

    that under sufficient realistic assump- tions the extended models are equivalent to standard Dolev-Yao models by the the RNTL projects EVA and Prouv´e, the ACI S´ecurit´e Informatique Rossignol, the ACI Cryptologie Psi-Robuste, and the ACI jeunes chercheurs "S´ecurit´e informatique, protocoles cryptographiques et d´etection d

  13. Fluid limit of nonintegrable continuous-time random walks in terms of fractional differential equations

    E-Print Network [OSTI]

    van Milligen, Boudewijn

    Laboratory, Oak Ridge, Tennessee 37831, USA 3 Laboratorio Nacional de Fusión, Asociación EURATOM-CIEMAT

  14. Local waiting time fluctuations along a randomly pinned crack front Knut Jrgen Maly,1

    E-Print Network [OSTI]

    Toussaint, Renaud

    that the fracture front dynamics is governed by local and irregular avalanches with very large size and velocity a characteristic length scale of disorder Ld 15µm, the avalanche clusters become anisotropic, and the scaling- ting contact lines [13­15], where elasticity and disorder compete to shape the interface. In order

  15. Local Waiting Time Fluctuations along a Randomly Pinned Crack Front Knut Jrgen Maly,1

    E-Print Network [OSTI]

    Schmittbuhl, Jean

    is followed using a high resolution fast camera. We show that the fracture front dynamics is governed by local:7 0:1. Above a characteristic length scale of disorder Ld 15 m, the avalanche clusters become elas- ticity and disorder compete to shape the interface. In order to shed some light

  16. TIME REVERSAL FOR WAVES IN RANDOM MEDIA GUILLAUME BAL AND LEONID RYZHIK y

    E-Print Network [OSTI]

    Bal, Guillaume

    medium have found important applications in medicine, non-destructive testing, underwater acoustics. The interference of multiple paths will thus be constructive at the source location and destructive anywhere else

  17. TIME REVERSAL AND REFOCUSING IN RANDOM MEDIA GUILLAUME BAL AND LEONID RYZHIK y

    E-Print Network [OSTI]

    Ryzhik, Lenya

    medium have found important applications in medicine, non-destructive testing, underwater acoustics. The interference of multiple paths will thus be constructive at the source location and destructive anywhere else

  18. Sharp asymptotics for the partition function of some continuous-time directed polymers

    E-Print Network [OSTI]

    Viens, Frederi G.

    Sharp asymptotics for the partition function of some continuous-time directed polymers Agnese Cadel This paper is concerned with two related types of directed polymers in a random medium. The rst one is a d regime of the objects under consideration. Key words and phrases: Polymer model, Random medium, Gaussian

  19. Sharp asymptotics for the partition function of some continuous-time directed polymers

    E-Print Network [OSTI]

    Tindel, Samy - Institut de Mathématiques Élie Cartan, Université Henri Poincaré

    Sharp asymptotics for the partition function of some continuous-time directed polymers Agnese Cadel This paper is concerned with two related types of directed polymers in a random medium. The first one is a d under consideration. Key words and phrases: Polymer model, Random medium, Gaussian field, Free energy

  20. Improving Ramsey spectroscopy in the extreme-ultraviolet region with a random-sampling approach

    SciTech Connect (OSTI)

    Eramo, R.; Bellini, M. [Istituto Nazionale di Ottica (INO-CNR), Largo E. Fermi 6, I-50125 Florence (Italy); European Laboratory for Non-linear Spectroscopy (LENS), I-50019 Sesto Fiorentino, Florence (Italy); Corsi, C.; Liontos, I. [European Laboratory for Non-linear Spectroscopy (LENS), I-50019 Sesto Fiorentino, Florence (Italy); Cavalieri, S. [European Laboratory for Non-linear Spectroscopy (LENS), I-50019 Sesto Fiorentino, Florence (Italy); Department of Physics, University of Florence, I-50019 Sesto Fiorentino, Florence (Italy)

    2011-04-15

    Ramsey-like techniques, based on the coherent excitation of a sample by delayed and phase-correlated pulses, are promising tools for high-precision spectroscopic tests of QED in the extreme-ultraviolet (xuv) spectral region, but currently suffer experimental limitations related to long acquisition times and critical stability issues. Here we propose a random subsampling approach to Ramsey spectroscopy that, by allowing experimentalists to reach a given spectral resolution goal in a fraction of the usual acquisition time, leads to substantial improvements in high-resolution spectroscopy and may open the way to a widespread application of Ramsey-like techniques to precision measurements in the xuv spectral region.

  1. Time Reversal Violation

    SciTech Connect (OSTI)

    Quinn, H; /SLAC

    2009-01-27

    This talk briefly reviews three types of time-asymmetry in physics, which I classify as universal, macroscopic and microscopic. Most of the talk is focused on the latter, namely the violation of T-reversal invariance in particle physics theories. In sum tests of microscopic T-invariance, or observations of its violation, are limited by the fact that, while we can measure many processes, only in very few cases can we construct a matched pair of process and inverse process and observe it with sufficient sensitivity to make a test. In both the cases discussed here we can achieve an observable T violation making use of flavor tagging, and in the second case also using the quantum properties of an antisymmetric coherent state of two B mesons to construct a CP-tag. Both these tagging properties depend only on very general properties of the flavor and/or CP quantum numbers and so provide model independent tests for T-invariance violations. The microscopic laws of physics are very close to T-symmetric. There are small effects that give CP- and T-violating processes in three-generation-probing weak decays. Where a T-violating observable can be constructed we see the relationships between T-violation and CP-violation expected in a CPT conserving theory. These microscopic effects are unrelated to the 'arrow of time' that is defined by increasing entropy, or in the time direction defined by the expansion of our Universe.

  2. Partition Testing versus Random Testing: the Influence of Uncertainty

    E-Print Network [OSTI]

    Gutjahr, Walter

    detection, partition test­ ing, program testing, random testing, software testing. I. Introduction Few topics in software testing methodology seem to be more controversial than the question whetherPartition Testing versus Random Testing: the Influence of Uncertainty Walter J. Gutjahr Department

  3. HOMOGENEOUS 1-BASED STRUCTURES AND INTERPRETABILITY IN RANDOM STRUCTURES

    E-Print Network [OSTI]

    Djordjevic, Vera

    HOMOGENEOUS 1-BASED STRUCTURES AND INTERPRETABILITY IN RANDOM STRUCTURES VERA KOPONEN Abstract. Let -structure which is homogeneous, simple and 1- based. The rst main result says that if M is, in addition, primitive, then it is strongly interpretable in a random structure. The second main result, which

  4. GENERATION AND RANDOM GENERATION: FROM SIMPLE GROUPS TO MAXIMAL SUBGROUPS

    E-Print Network [OSTI]

    Burness, Tim

    GENERATION AND RANDOM GENERATION: FROM SIMPLE GROUPS TO MAXIMAL SUBGROUPS TIMOTHY C. BURNESS of generators for G. It is well known that d(G) = 2 for all (non-abelian) finite simple groups. We prove that d investigate the random generation of maximal subgroups of simple and almost simple groups. By applying

  5. Forest fires, explosions, and random trees Edward Crane

    E-Print Network [OSTI]

    Wirosoetisno, Djoko

    Forest fires, explosions, and random trees Edward Crane HIMR, UoB 13th January 2014 #12 and James Martin at the University of Oxford. Edward Crane (HIMR, UoB) Forest fires, explosions, and random trees 13th January 2014 2 / 20 #12;Overview This talk is about the mean field forest fire model

  6. Sharp Generalization Error Bounds for Randomly-projected Classifiers

    E-Print Network [OSTI]

    Kaban, Ata

    ;Introduction (2) Our aim is to obtain generalisation bound for a generic linear classifier trained by ERM for a generic linear classifier trained by ERM on randomly projected data. Make no restrictive assumptions other trained by ERM on randomly projected data. Make no restrictive assumptions other than the original data

  7. LONG WAVE EXPANSIONS FOR WATER WAVES OVER RANDOM TOPOGRAPHY

    E-Print Network [OSTI]

    LONG WAVE EXPANSIONS FOR WATER WAVES OVER RANDOM TOPOGRAPHY ANNE DE BOUARD 1 , WALTER CRAIG 2 with the ran­ dom bottom. We show that the resulting influence of the random topography is expressed in terms of bottom topography a#ects the equations describing the limit of solutions in the long wave regime. We

  8. RANDOM REALS AND 1 (1, ( : ))2 J. TATCH MOORE

    E-Print Network [OSTI]

    Moore, Justin Tatch

    the results of J. Barnett and S. Todorcevi´c concerning the influence MA1 has on random graphs. I of random reals. 1. Introduction The focus of this note is to extend J. Barnett's result in [2] that 1 (1 of MA1 . Also, in [1] Barnett has shown that the stronger partition relation 1 (1, ( : 1))2 holds

  9. Utility-Optimal Random Access for Wireless Multimedia Networks

    E-Print Network [OSTI]

    Wong, Vincent

    Utility-Optimal Random Access for Wireless Multimedia Networks Man Hon Cheung, Hamed Mohsenian-of-service (QoS) requirements, we model their utilities with concave, step, and quasi-concave functions. We to the users for random access, based on solving a non-convex network utility maximization problem. We propose

  10. FAST COMPRESSIVE SAMPLING WITH STRUCTURALLY RANDOM MATRICES Thong T. Do

    E-Print Network [OSTI]

    FAST COMPRESSIVE SAMPLING WITH STRUCTURALLY RANDOM MATRICES Thong T. Do , Trac D. Tran and Lu Gan of fast and efficient com- pressive sampling based on the new concept of structurally random matrices low complexity and fast computation based on block processing and linear filtering. (iv

  11. On the Impossibility of Cryptography with Tamperable Randomness

    E-Print Network [OSTI]

    International Association for Cryptologic Research (IACR)

    On the Impossibility of Cryptography with Tamperable Randomness Per Austrin , Kai-Min Chung of the security of cryptographic primitives in the presence of efficient tampering attacks to the randomness of honest parties. More precisely, we consider p-tampering attackers that may efficiently tamper with each

  12. Trading Structure for Randomness in Wireless Opportunistic Szymon Chachulski

    E-Print Network [OSTI]

    for Randomness in Wireless Opportunistic Routing by Szymon Chachulski Submitted to the Department of ElectricalTrading Structure for Randomness in Wireless Opportunistic Routing by Szymon Chachulski mgr inz., Warsaw University of Technology (2005) Submitted to the Department of Electrical Engineering and Computer

  13. Critical behavior in inhomogeneous random graphs Remco van der Hofstad

    E-Print Network [OSTI]

    Hofstad, Remco van der

    Critical behavior in inhomogeneous random graphs Remco van der Hofstad June 10, 2010 Abstract We study the critical behavior of inhomogeneous random graphs where edges are present independently but with unequal edge occupation probabilities. The edge probabilities are moderated by vertex weights

  14. k-Connectivity in Random Key Graphs with Unreliable Links

    E-Print Network [OSTI]

    Yagan, Osman

    of Eschenauer and Gligor for securing wireless sensor network (WSN) communications. Random key graphs have real-world networks; e.g., with secure WSN application in mind, link unreliability can be attributed for securing WSN communications is the random predistribution of cryptographic keys to sensor nodes

  15. Choosing a Random Peer in Chord Valerie King

    E-Print Network [OSTI]

    Saia, Jared

    sampling is a fundamental statistical operation; a function which chooses a random peer can be used). Our motivation for studying this problem is threefold: to enable data collection by statistically rig-to-peer networks; and to support the creation and maintenance of random links, and thereby offer a simple means

  16. Energy Scaling Laws for Distributed Inference in Random Fusion Networks

    E-Print Network [OSTI]

    Yukich, Joseph E.

    1 Energy Scaling Laws for Distributed Inference in Random Fusion Networks Animashree Anandkumar Abstract--The energy scaling laws of multihop data fusion networks for distributed inference are considered. The fusion network consists of randomly located sensors distributed i.i.d. according to a general spatial

  17. An Efficient Method for Random Delay Generation in Embedded Software

    E-Print Network [OSTI]

    International Association for Cryptologic Research (IACR)

    An Efficient Method for Random Delay Generation in Embedded Software Jean-S´ebastien Coron and Ilya Process Interrupts (rpi) as well as in software by placing "dummy" cy- cles at some points of the program. We give preliminary information on software random delays in Sect. 2. Related work. First detailed

  18. Continuum Cascade Model: Branching Random Walk for Traveling Wave

    E-Print Network [OSTI]

    Yoshiaki Itoh

    2015-07-15

    The food web is a directed graph in which nodes label species and directed links represent the predation between species. Cascade models generate random food webs. The recursion to obtain the probability distribution of the longest chain length has the solution with traveling wave. We consider a branching random walk to study the asymptotic probability on the wave front.

  19. Explanation of the Random Lengths Framing Lumber Composite Price

    E-Print Network [OSTI]

    Explanation of the Random Lengths Framing Lumber Composite Price May 10, 2006 The Random Lengths Framing Lumber Composite is a broad measure of price behavior in the U.S. framing lumber market prices, 33% comes from Western U.S. prices, and 34% comes from Canadian prices. The Composite does

  20. Type Systems For Polynomial-time Computation 

    E-Print Network [OSTI]

    Hofmann, Martin

    This thesis introduces and studies a typed lambda calculus with higher-order primitive recursion over inductive datatypes which has the property that all definable number-theoretic functions are polynomial time computable. ...

  1. Smectic Liquid Crystals in Random Environments

    E-Print Network [OSTI]

    Leo Radzihovsky; John Toner

    1999-06-04

    We study smectic liquid crystals in random environments, e.g., aerogel. A low temperature analysis reveals that even arbitrarily weak quenched disorder (i.e., arbitrarily low aerogel density) destroys translational (smectic) order. A harmonic approximation to the elastic energy suggests that there is no ``smectic Bragg glass'' phase in this system: even at zero temperature, it is riddled with dislocation loops induced by the quenched disorder. This result implies the destruction of orientational (nematic) order as well, and that the thermodynamically sharp Nematic-Smectic-A transition is destroyed by disorder, in agreement with recent experimental results. We also show that the anharmonic elastic terms neglected in the above treatment are important (i.e., are ``relevant'' in the renormalization group sense); whether they alter the above conclusions about the smectic Bragg glass, orientational disorder, and the existence of sharp transitions, remains an open question. However, they do not alter our conclusion that translational (smectic) order is always destroyed. In contrast, we expect that weak annealed disorder should have no qualitative effects on the smectic order.

  2. Collisions of particles advected in random flows

    E-Print Network [OSTI]

    K. Gustavsson; B. Mehlig; M. Wilkinson

    2008-01-18

    We consider collisions of particles advected in a fluid. As already pointed out by Smoluchowski [Z. f. physik. Chemie XCII, 129-168, (1917)], macroscopic motion of the fluid can significantly enhance the frequency of collisions between the suspended particles. This effect was invoked by Saffman and Turner [J. Fluid Mech. 1, 16-30, (1956)] to estimate collision rates of small water droplets in turbulent rain clouds, the macroscopic motion being caused by turbulence. Here we show that the Saffman-Turner theory is unsatisfactory because it describes an initial transient only. The reason for this failure is that the local flow in the vicinity of a particle is treated as if it were a steady hyperbolic flow, whereas in reality it must fluctuate. We derive exact expressions for the steady-state collision rate for particles suspended in rapidly fluctuating random flows and compute how this steady state is approached. For incompressible flows, the Saffman-Turner expression is an upper bound.

  3. Uncovering Randomness and Success in Society

    E-Print Network [OSTI]

    Jalan, Sarika; Madhusudanan, Anagha; Dwivedi, Sanjiv Kumar

    2014-01-01

    An understanding of how individuals shape and impact the evolution of society is vastly limited due to the unavailability of large-scale reliable datasets that can simultaneously capture information regarding individual movements and social interactions. We believe that the popular Indian film industry, 'Bollywood', can provide a social network apt for such a study. Bollywood provides massive amounts of real, unbiased data that spans more than 100 years, and hence this network has been used as a model for the present paper. The nodes which maintain a moderate degree or widely cooperate with the other nodes of the network tend to be more fit (measured as the success of the node in the industry) in comparison to the other nodes. The analysis carried forth in the current work, using a conjoined framework of complex network theory and random matrix theory, aims to quantify the elements that determine the fitness of an individual node and the factors that contribute to the robustness of a network. The authors of t...

  4. Nonlinear Lattice Waves in Random Potentials

    E-Print Network [OSTI]

    Sergej Flach

    2014-09-10

    Localization of waves by disorder is a fundamental physical problem encompassing a diverse spectrum of theoretical, experimental and numerical studies in the context of metal-insulator transition, quantum Hall effect, light propagation in photonic crystals, and dynamics of ultra-cold atoms in optical arrays. Large intensity light can induce nonlinear response, ultracold atomic gases can be tuned into an interacting regime, which leads again to nonlinear wave equations on a mean field level. The interplay between disorder and nonlinearity, their localizing and delocalizing effects is currently an intriguing and challenging issue in the field. We will discuss recent advances in the dynamics of nonlinear lattice waves in random potentials. In the absence of nonlinear terms in the wave equations, Anderson localization is leading to a halt of wave packet spreading. Nonlinearity couples localized eigenstates and, potentially, enables spreading and destruction of Anderson localization due to nonintegrability, chaos and decoherence. The spreading process is characterized by universal subdiffusive laws due to nonlinear diffusion. We review extensive computational studies for one- and two-dimensional systems with tunable nonlinearity power. We also briefly discuss extensions to other cases where the linear wave equation features localization: Aubry-Andre localization with quasiperiodic potentials, Wannier-Stark localization with dc fields, and dynamical localization in momentum space with kicked rotors.

  5. Equilibrium ultrastable glasses produced by random pinning

    E-Print Network [OSTI]

    Glen M Hocky; Ludovic Berthier; David R. Reichman

    2014-12-08

    Ultrastable glasses have risen to prominence due to their potentially useful material properties and the tantalizing possibility of a general method of preparation via vapor deposition. Despite the importance of this novel class of amorphous materials, numerical studies have been scarce because achieving ultrastability in atomistic simulations is an enormous challenge. Here we bypass this difficulty and establish that randomly pinning the position of a small fraction of particles inside an equilibrated supercooled liquid generates ultrastable configurations at essentially no numerical cost, while avoiding undesired structural changes due to the preparation protocol. Building on the analogy with vapor-deposited ultrastable glasses, we study the melting kinetics of these configurations following a sudden temperature jump into the liquid phase. In homogeneous geometries, we find that enhanced kinetic stability is accompanied by large scale dynamic heterogeneity, while a competition between homogeneous and heterogeneous melting is observed when a liquid boundary invades the glass at constant velocity. Our work demonstrates the feasibility of large-scale, atomistically resolved, and experimentally relevant simulations of the kinetics of ultrastable glasses.

  6. Time correlation of cosmic-ray-induced neutrons and gamma rays at sea level

    E-Print Network [OSTI]

    Harilal, S. S.

    Time correlation of cosmic-ray-induced neutrons and gamma rays at sea level G. Miloshevsky n , A and evaporation processes of air nuclei are time-correlated. The occurrence of their counts in a fixed time interval is not a random (Poisson) distribution, but rather time-correlated bursts of counts

  7. RANDOM COEFFICIENT H MODE CONFINEMENT SCALINGS

    E-Print Network [OSTI]

    ;nement time for most other machines, we are e#11;ectively penalising ASDEX. This small penalty may device scalings are more uniform and closer to standard L mode con#12;nement scaling. To model

  8. Random matrices and chaos in nuclear physics: Nuclear structure

    SciTech Connect (OSTI)

    Weidenmueller, H. A.; Mitchell, G. E. [Max-Planck-Institut fuer Kernphysik, D-69029 Heidelberg (Germany); North Carolina State University, Raleigh, North Carolina 27695 (United States) and Triangle Universities Nuclear Laboratory, Durham, North Carolina 27706 (United States)

    2009-04-15

    Evidence for the applicability of random-matrix theory to nuclear spectra is reviewed. In analogy to systems with few degrees of freedom, one speaks of chaos (more accurately, quantum chaos) in nuclei whenever random-matrix predictions are fulfilled. An introduction into the basic concepts of random-matrix theory is followed by a survey over the extant experimental information on spectral fluctuations, including a discussion of the violation of a symmetry or invariance property. Chaos in nuclear models is discussed for the spherical shell model, for the deformed shell model, and for the interacting boson model. Evidence for chaos also comes from random-matrix ensembles patterned after the shell model such as the embedded two-body ensemble, the two-body random ensemble, and the constrained ensembles. All this evidence points to the fact that chaos is a generic property of nuclear spectra, except for the ground-state regions of strongly deformed nuclei.

  9. Randomized Algorithms and Lower Bounds for Quantum Simulation

    E-Print Network [OSTI]

    Chi Zhang

    2009-10-21

    We consider deterministic and {\\em randomized} quantum algorithms simulating $e^{-iHt}$ by a product of unitary operators $e^{-iA_jt_j}$, $j=1,...,N$, where $A_j\\in\\{H_1,...,H_m\\}$, $H=\\sum_{i=1}^m H_i$ and $t_j > 0$ for every $j$. Randomized algorithms are algorithms approximating the final state of the system by a mixed quantum state. First, we provide a scheme to bound the trace distance of the final quantum states of randomized algorithms. Then, we show some randomized algorithms, which have the same efficiency as certain deterministic algorithms, but are less complicated than their opponentes. Moreover, we prove that both deterministic and randomized algorithms simulating $e^{-iHt}$ with error $\\e$ at least have $\\Omega(t^{3/2}\\e^{-1/2})$ exponentials.

  10. Comment "On the statistics of the product of a Gaussian process and a pseudo random binary code" 

    E-Print Network [OSTI]

    Painter, John H.; Jacobs, I.

    1966-01-01

    908 PROCEEDINGS OF THE IEEE JUNE Comment "On the Statistics of the Product of a Gaussian Process and a Pseudo Random Binary Code" In a recent correspondence, Painter' shows that the first-order statistics of the product of a Gaussian noise... functions C(t) contain an infinite number of jump discontinuities; hence, almost all sample functions of Z(t) contain jump discontinuities. However, for a stationary Gaussian process, Manuscript received March 2.1966. 1 J. H. Painter. Proc. IEEE...

  11. Could Planck level physics be driving classical macroscopic physics through a random walk?

    E-Print Network [OSTI]

    C. L. Herzenberg

    2011-11-28

    We examine a very simple conceptual model of stochastic behavior based on a random walk process in velocity space. For objects engaged in classical non-relativistic velocities, this leads under asymmetric conditions to acceleration processes that resemble the behavior of objects subject to Newton's second law, and in three dimensional space, acceleration dependent on an inverse square law emerges. Thus, a non-relativistic random walk would appear to be capable of describing certain prominent features of classical physics; however, this classical behavior appears to be able to take place only for objects with mass exceeding a threshold value which we identify with the Planck mass. Under these circumstances, stochastic space-time displacements would be smaller than the Planck length and the Planck time so that such classically behaved objects would be effectively localized. Lower mass objects exhibit more rapid diffusion and less localization, and a relativistic random walk would seem to be required of objects having masses comparable to and smaller than the threshold mass value. Results suggest the possibility of an intrinsic quantum-classical transition in the microgram mass range.

  12. Tip sheet: Expanded Library of Congress Call Number Classification system Call Number Subject Matter

    E-Print Network [OSTI]

    Kambhampati, Patanjali

    Tip sheet: Expanded Library of Congress Call Number Classification system Call Number Subject R: Medicine T: Technology U: Military Science Z: Bibliography. Library Science. Information

  13. Analyzing Cascading Failures in Smart Grids under Random and Targeted Attacks

    E-Print Network [OSTI]

    Ruj, Sushmita

    2015-01-01

    We model smart grids as complex interdependent networks, and study targeted attacks on smart grids for the first time. A smart grid consists of two networks: the power network and the communication network, interconnected by edges. Occurrence of failures (attacks) in one network triggers failures in the other network, and propagates in cascades across the networks. Such cascading failures can result in disintegration of either (or both) of the networks. Earlier works considered only random failures. In practical situations, an attacker is more likely to compromise nodes selectively. We study cascading failures in smart grids, where an attacker selectively compromises the nodes with probabilities proportional to their degrees; high degree nodes are compromised with higher probability. We mathematically analyze the sizes of the giant components of the networks under targeted attacks, and compare the results with the corresponding sizes under random attacks. We show that networks disintegrate faster for targeted...

  14. Random walk hierarchy measure: What is more hierarchical, a chain, a tree or a star?

    E-Print Network [OSTI]

    Czégel, Dániel

    2015-01-01

    Signs of hierarchy are prevalent in a wide range of systems in nature and society. One of the key problems is quantifying the importance of hierarchical organisation in the structure of the network representing the interactions or connections between the fundamental units of the studied system. Although a number of notable methods are already available, their vast majority is treating all directed acyclic graphs as already maximally hierarchical. Here we propose a hierarchy measure based on random walks on the network. The novelty of our approach is that directed trees corresponding to multi level pyramidal structures obtain higher hierarchy scores compared to directed chains and directed stars. Furthermore, in the thermodynamic limit the hierarchy measure of regular trees is converging to a well defined limit depending only on the branching number. When applied to real networks, our method is computationally very effective, as the result can be evaluated with arbitrary precision by subsequent multiplications...

  15. UGE Scheduler Cycle Time

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    UGE Scheduler Cycle Time UGE Scheduler Cycle Time Genepool Cycle Time Genepool Daily Genepool Weekly Phoebe Cycle Time Phoebe Daily Phoebe Weekly What is the Scheduler Cycle? The...

  16. Time and Labor Manual -Time Keepers -LSUSH

    E-Print Network [OSTI]

    Time and Labor Manual - Time Keepers - LSUSH Version Date: July 2012 #12;COPYRIGHT & TRADEMARKS create a risk of personal injury. If you use this software in dangerous applications, then you shall Guide Time and Labor Manual - Time Keepers - LSUSH Page iii Table of Contents Time and Labor Manual

  17. Top eigenvalue of a random matrix: A tale of Satya N. Majumdar

    E-Print Network [OSTI]

    Udgaonkar, Jayant B.

    Top eigenvalue of a random matrix: A tale of tails Satya N. Majumdar Laboratoire de Physique Th, 2012 S.N. Majumdar Top eigenvalue of a random matrix: A tale of tails #12;First Appearence of Random Matrices S.N. Majumdar Top eigenvalue of a random matrix: A tale of tails #12;First Appearence of Random

  18. Bounds on Some Ramsey Numbers Involving Quadrilateral +

    E-Print Network [OSTI]

    Radziszowski, Stanislaw P.

    Bounds on Some Ramsey Numbers Involving Quadrilateral + Xiaodong Xu Guangxi Academy of Sciences@cs.rit.edu Abstract. For graphs G 1 , G 2 , · · · , Gm , the Ramsey number R(G 1 , G 2 , · · · , Gm ) is defined Ramsey numbers involving quadrilateral C 4 , including R(C 4 , K 9 ) # 32, 19 # R(C 4 , C 4 , K 4 ) # 22

  19. Predicting landfalling hurricane numbers from basin hurricane numbers: basic statistical analysis

    E-Print Network [OSTI]

    Laepple, T; Penzer, J; Bellone, E; Nzerem, K; Laepple, Thomas; Jewson, Stephen; Penzer, Jeremy; Bellone, Enrica; Nzerem, Kechi

    2007-01-01

    One possible method for predicting landfalling hurricane numbers is to first predict the number of hurricanes in the basin and then convert that prediction to a prediction of landfalling hurricane numbers using an estimated proportion. Should this work better than just predicting landfalling hurricane numbers directly? We perform a basic statistical analysis of this question in the context of a simple abstract model.

  20. Harmonic resolution as a holographic quantum number

    E-Print Network [OSTI]

    Bousso, Raphael

    2009-01-01

    LBNL- 57239 Harmonic resolution as a holographic quantumhep-th/0310223 UCB-PTH-03/26 Harmonic resolution as aquantum number, the harmonic resolution K. The Bekenstein