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they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
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1

Time Series Models: Hidden Markov Models  

E-Print Network [OSTI]

Time Series Models: Hidden Markov Models & Linear Dynamical Systems Sam Roweis Gatsby Computational before. Discrete state: { Moore and Mealy machines (engineering) { stochastic #12;nite state automata (CS chain with stochastic measurements. Gauss-Markov process in a pancake. PSfrag replacements x 1 y 1 x 2 y

Roweis, Sam

2

Time Series Models: Hidden Markov Models  

E-Print Network [OSTI]

Time Series Models: Hidden Markov Models & Linear Dynamical Systems Sam Roweis Gatsby Computational. Discrete state: { Moore and Mealy machines (engineering) { stochastic #12;nite state automata (CS with stochastic measurements. Gauss-Markov process in a pancake. PSfrag replacements x 1 y 1 x 2 y 2 x 3 y 3 x T y

Roweis, Sam

3

Univariate Modeling and Forecasting of Monthly Energy Demand Time Series  

E-Print Network [OSTI]

Univariate Modeling and Forecasting of Monthly Energy Demand Time Series Using Abductive and Neural demand time series based only on data for six years to forecast the demand for the seventh year. Both networks, Neural networks, Modeling, Forecasting, Energy demand, Time series forecasting, Power system

Abdel-Aal, Radwan E.

4

Analysis of Time Series Using Compact Model-Based Descriptions  

E-Print Network [OSTI]

Analysis of Time Series Using Compact Model-Based Descriptions Hans-Peter Kriegel, Peer Kr this is a combination of the coefficients 1, . . . , 3 representing the three input time series using a function f-of-the-art compression methods. The results are visually presented in a very concise way so that the user can easily

Kriegel, Hans-Peter

5

Bayesian time series models and scalable inference  

E-Print Network [OSTI]

With large and growing datasets and complex models, there is an increasing need for scalable Bayesian inference. We describe two lines of work to address this need. In the first part, we develop new algorithms for inference ...

Johnson, Matthew James, Ph. D. Massachusetts Institute of Technology

2014-01-01T23:59:59.000Z

6

1MaPhySto Workshop 9/04 Nonlinear Time Series ModelingNonlinear Time Series Modeling  

E-Print Network [OSTI]

. "Stylized facts" concerning financial time series 4. ARCH and GARCH models 5. Forecasting with GARCH 6 of multivariate RV equivalence 8.5 examples 8.6 Extremes for GARCH and SV models 8.7 Summary of results for ACF of GARCH & SV models #12;4MaPhySto Workshop 9/04 Part III: Nonlinear and NonGaussian State-Space Models 1

7

Time Series Models for Measuring Market Risk Time Series Models for Measuring Market Risk  

E-Print Network [OSTI]

and collaborative mixtures of experts 3 GARCH processes with non-parametric innovations 4 Conclusions and future Competitive and collaborative mixtures of experts 3 GARCH processes with non-parametric innovations 4 Volatility models: GARCH processes We say {rt}T t=1 follows a GARCH(1,1) process if: rt = tt (4) 2 t = + |rt

Hernández Lobato, José Miguel

8

Probabilistic time-series  

E-Print Network [OSTI]

SCIA 2003 Tutorial: Hidden Markov Models Sam Roweis, University of Toronto June 29, 2003 Probabilistic Generative Models for Time Series #15; Stochastic models for time-series: y 1 ; y 2 ; : : : ; y #15; Add noise to make the system stochastic: p(y t jy t 1 ;y t 2 ; : : : ;y t k ) #15; Markov models

Roweis, Sam

9

1Banff 6/06 Structural Break Detection in Time Series ModelsStructural Break Detection in Time Series Models  

E-Print Network [OSTI]

breaks in this series? #12;5Banff 6/06 Introduction Examples AR GARCH Stochastic volatility State space Simulation results Applications Simulation results for GARCH and SV models #12;6Banff 6/06 Examples 1 ),,( 1 jjpj K #12;7Banff 6/06 Examples (cont) 2. Segmented GARCH model: where 0 = 1

10

1NCAR-IMAGe 2006 Structural Break Detection in Time Series ModelsStructural Break Detection in Time Series Models  

E-Print Network [OSTI]

-202 Any breaks in this series? #12;5NCAR-IMAGe 2006 Introduction Examples AR GARCH Stochastic volatility break estimation Simulation results Applications Simulation results for GARCH and SV models #12;6NCAR-tjptjptjjt tYYY jj GARCH model

11

Introduction to (Generalized) Autoregressive Conditional Heteroskedasticity Models in Time Series  

E-Print Network [OSTI]

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 4 ARCH/GARCH models 8 4.1 Sample Application and application of the ARCH/GARCH models proposed in the 1980's by econometricians such as Robert Engle (who won at the time). In particular, we focus on the paper, "GARCH 101: The Use of ARCH/GARCH Models in Applied Econo

Morrow, James A.

12

Early Classification of Multivariate Time Series Using a Hybrid HMM/SVM model  

E-Print Network [OSTI]

Early Classification of Multivariate Time Series Using a Hybrid HMM/SVM model Mohamed F. Ghalwash to use a shorter time interval for classification is often more favorable than having a slightly more with other models that use full time series both in training and testing. Analysis of biomedical data has

Obradovic, Zoran

13

Time series modeling and large scale global solar radiation forecasting from geostationary satellites data  

E-Print Network [OSTI]

1 Time series modeling and large scale global solar radiation forecasting from geostationary global solar radiation. In this paper, we use geostationary satellites data to generate 2-D time series of solar radiation for the next hour. The results presented in this paper relate to a particular territory

Paris-Sud XI, Université de

14

A FAST MODEL-BUILDING METHOD FOR TIME SERIES USING GENETIC PROGRAMMING  

E-Print Network [OSTI]

A FAST MODEL-BUILDING METHOD FOR TIME SERIES USING GENETIC PROGRAMMING I. Yoshihara Faculty) financial problems e.g. stock price indices and gold prices. The experiments lead us to the conclusion

Fernandez, Thomas

15

1Kaiserslautern 9/05 Structural Break Detection in Time Series ModelsStructural Break Detection in Time Series Models  

E-Print Network [OSTI]

Regressive Modeling 4 pieces, 2.58 seconds. #12;4Kaiserslautern 9/05 Introduction Examples AR GARCH Stochastic for structural break estimation Simulation results Applications Simulation results for GARCH and SSM #12. Segmented GARCH model: where 0 = 1

16

Time series models with an EGB2 conditional distribution  

E-Print Network [OSTI]

: Theory and Methods. John Wiley & Sons Ltd. McDonald,. J.B. and White, S. B. (1993) A comparison of some robust, adaptive, and partially adaptive estimators of regression models. Econo- metric Reviews 12, 103-124 McDonald J. B. and Xu, Y. J. (1995) A... generalization of the beta distrib- ution with applications. Journal of Econometrics 66, 133-152. McNeil, A.J., Frey, R. and Embrechts, P. (2005) Quantitative Risk Manage- ment. Princeton: Princeton University Press. Prentice, R. L. (1975) Discrimination among...

Caivano, Michele; Harvey, Andrew

2014-07-09T23:59:59.000Z

17

Volatility Forecasts in Financial Time Series with HMM-GARCH Models  

E-Print Network [OSTI]

Volatility Forecasts in Financial Time Series with HMM-GARCH Models Xiong-Fei Zhuang and Lai {xfzhuang,lwchan}@cse.cuhk.edu.hk Abstract. Nowadays many researchers use GARCH models to generate of the two parameters G1 and A1[1], in GARCH models is usually too high. Since volatility forecasts in GARCH

Chen, Yiling

18

TIME SERIES MODELS OF THREE SETS OF RXTE OBSERVATIONS OF 4U 1543-47  

SciTech Connect (OSTI)

The X-ray nova 4U 1543-47 was in a different physical state (low/hard, high/soft, and very high) during the acquisition of each of the three time series analyzed in this paper. Standard time series models of the autoregressive moving average (ARMA) family are fitted to these series. The low/hard data can be adequately modeled by a simple low-order model with fixed coefficients, once the slowly varying mean count rate has been accounted for. The high/soft series requires a higher order model, or an ARMA model with variable coefficients. The very high state is characterized by a succession of 'dips', with roughly equal depths. These seem to appear independently of one another. The underlying stochastic series can again be modeled by an ARMA form, or roughly as the sum of an ARMA series and white noise. The structuring of each model in terms of short-lived aperiodic and 'quasi-periodic' components is discussed.

Koen, C. [Department of Statistics, University of the Western Cape, Private Bag X17, Bellville, 7535 Cape (South Africa)] [Department of Statistics, University of the Western Cape, Private Bag X17, Bellville, 7535 Cape (South Africa)

2013-03-01T23:59:59.000Z

19

CHANGE OF STRUCTURE IN FINANCIAL TIME SERIES, LONG RANGE DEPENDENCE AND THE GARCH MODEL  

E-Print Network [OSTI]

CHANGE OF STRUCTURE IN FINANCIAL TIME SERIES, LONG RANGE DEPENDENCE AND THE GARCH MODEL THOMAS having as limit a Gaussian #12;eld. In the case of GARCH(p; q) processes a statistic closely related limit theorem for this statistic under the hypothesis of a GARCH(p; q) sequence with a #12;nite 4th

Mikosch, Thomas

20

Time Series Prediction by Chaotic Modeling of Nonlinear Dynamical Systems Arslan Basharat+  

E-Print Network [OSTI]

Inc. Clifton Park, NY, USA arslan.basharat@kitware.com Mubarak Shah+ + University of Central Florida Orlando, FL, USA shah@cs.ucf.edu Abstract We use concepts from chaos theory in order to model nonlinear dynamical systems that exhibit deterministic be- havior. Observed time series from such a system can be em

Central Florida, University of

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


21

Some methods and models for analyzing time-series gene expression data  

E-Print Network [OSTI]

Experiments in a variety of fields generate data in the form of a time-series. Such time-series profiles, collected sometimes for tens of thousands of experiments, are a challenge to analyze and explore. In this work, ...

Jammalamadaka, Arvind K. (Arvind Kumar), 1981-

2009-01-01T23:59:59.000Z

22

Abstract--Meteorological time series are characterized by important spatial and temporal variation. Model determination and  

E-Print Network [OSTI]

of the meteorological time series used, which includes the use of statistical techniques to detect whether there exist for the time series using an evolutionary algorithm that adaptively adjusts some of its parameters during its and temperatures collected in a region of Romania. The results are promising for the analysis of such time series

Fernandez, Thomas

23

Proceedings of Student Research Day, CSIS, Pace University, May 9th, 2003 Modeling Economic Time Series Using a Focused Time Lagged  

E-Print Network [OSTI]

Series Using a Focused Time Lagged FeedForward Neural Network N. Moseley ABSTRACT, - Artificial neural other series expansion.[2]. The motivation for analysis of time series using neural netwoProceedings of Student Research Day, CSIS, Pace University, May 9th, 2003 Modeling Economic Time

Tappert, Charles

24

Time series modeling and large scale global solar radiation forecasting from geostationary satellites data  

E-Print Network [OSTI]

When a territory is poorly instrumented, geostationary satellites data can be useful to predict global solar radiation. In this paper, we use geostationary satellites data to generate 2-D time series of solar radiation for the next hour. The results presented in this paper relate to a particular territory, the Corsica Island, but as data used are available for the entire surface of the globe, our method can be easily exploited to another place. Indeed 2-D hourly time series are extracted from the HelioClim-3 surface solar irradiation database treated by the Heliosat-2 model. Each point of the map have been used as training data and inputs of artificial neural networks (ANN) and as inputs for two persistence models (scaled or not). Comparisons between these models and clear sky estimations were proceeded to evaluate the performances. We found a normalized root mean square error (nRMSE) close to 16.5% for the two best predictors (scaled persistence and ANN) equivalent to 35-45% related to ground measurements. F...

Voyant, Cyril; Muselli, Marc; Paoli, Christophe; Nivet, Marie Laure

2014-01-01T23:59:59.000Z

25

IMPROVED SEMI-PARAMETRIC TIME SERIES MODELS OF AIR POLLUTION AND MORTALITY  

E-Print Network [OSTI]

series analyses of air pollution and health attracted the attention of the scientific community, policy uncertainty in time series studies of air pollution and health. This discovery delayed the completion) for six "criteria" air pollutants at a level that protects the public's health (Environmental Protection

Dominici, Francesca

26

Multi-horizon solar radiation forecasting for Mediterranean locations using time series models  

E-Print Network [OSTI]

Considering the grid manager's point of view, needs in terms of prediction of intermittent energy like the photovoltaic resource can be distinguished according to the considered horizon: following days (d+1, d+2 and d+3), next day by hourly step (h+24), next hour (h+1) and next few minutes (m+5 e.g.). Through this work, we have identified methodologies using time series models for the prediction horizon of global radiation and photovoltaic power. What we present here is a comparison of different predictors developed and tested to propose a hierarchy. For horizons d+1 and h+1, without advanced ad hoc time series pre-processing (stationarity) we find it is not easy to differentiate between autoregressive moving average (ARMA) and multilayer perceptron (MLP). However we observed that using exogenous variables improves significantly the results for MLP . We have shown that the MLP were more adapted for horizons h+24 and m+5. In summary, our results are complementary and improve the existing prediction techniques ...

Voyant, Cyril; Muselli, Marc; Nivet, Marie Laure

2013-01-01T23:59:59.000Z

27

Biomedical time series analysis based on bag-of-words model.  

E-Print Network [OSTI]

??This research proposes a number of new methods for biomedical time series classification and clustering based on a novel Bag-of-Words (BoW) representation. It is anticipated… (more)

Wang, Jin

2013-01-01T23:59:59.000Z

28

A Fuzzy-Convolution Model for Physical Action and Behaviour Pattern Recognition of 3D Time Series  

E-Print Network [OSTI]

A Fuzzy-Convolution Model for Physical Action and Behaviour Pattern Recognition of 3D Time Series-- Pattern Classification, Action Recognition, Fuzzy Classifiers, Signal Convolution. I. INTRODUCTION researchers in pattern recognition on the field of intelligent surveillance. Fuzzy logic has been extensively

Hu, Huosheng

29

Statistical criteria for characterizing irradiance time series.  

SciTech Connect (OSTI)

We propose and examine several statistical criteria for characterizing time series of solar irradiance. Time series of irradiance are used in analyses that seek to quantify the performance of photovoltaic (PV) power systems over time. Time series of irradiance are either measured or are simulated using models. Simulations of irradiance are often calibrated to or generated from statistics for observed irradiance and simulations are validated by comparing the simulation output to the observed irradiance. Criteria used in this comparison should derive from the context of the analyses in which the simulated irradiance is to be used. We examine three statistics that characterize time series and their use as criteria for comparing time series. We demonstrate these statistics using observed irradiance data recorded in August 2007 in Las Vegas, Nevada, and in June 2009 in Albuquerque, New Mexico.

Stein, Joshua S.; Ellis, Abraham; Hansen, Clifford W.

2010-10-01T23:59:59.000Z

30

Benchmarking of energy time series  

SciTech Connect (OSTI)

Benchmarking consists of the adjustment of time series data from one source in order to achieve agreement with similar data from a second source. The data from the latter source are referred to as the benchmark(s), and often differ in that they are observed at a lower frequency, represent a higher level of temporal aggregation, and/or are considered to be of greater accuracy. This report provides an extensive survey of benchmarking procedures which have appeared in the statistical literature, and reviews specific benchmarking procedures currently used by the Energy Information Administration (EIA). The literature survey includes a technical summary of the major benchmarking methods and their statistical properties. Factors influencing the choice and application of particular techniques are described and the impact of benchmark accuracy is discussed. EIA applications and procedures are reviewed and evaluated for residential natural gas deliveries series and coal production series. It is found that the current method of adjusting the natural gas series is consistent with the behavior of the series and the methods used in obtaining the initial data. As a result, no change is recommended. For the coal production series, a staged approach based on a first differencing technique is recommended over the current procedure. A comparison of the adjustments produced by the two methods is made for the 1987 Indiana coal production series. 32 refs., 5 figs., 1 tab.

Williamson, M.A.

1990-04-01T23:59:59.000Z

31

Segmenting Time Series for Weather Forecasting  

E-Print Network [OSTI]

) models is summarised as weather forecast texts. In the domain of gas turbines, sensor data from an operational gas turbine is summarised for the maintenance engineers. More details on SUMTIME have been to develop a generic model for summarisation of time series data. Initially, we have applied standard

Sripada, Yaji

32

Temporal Resolution in Time Series and Probabilistic Models of Renewable Power Eric Hoevenaars  

E-Print Network [OSTI]

. . . . . . . . . . . . . . . . . . . . . . . 12 2.2.2 Solar Photovoltaic Model . . . . . . . . . . . . . . . . . . . . . 16 2.2.3 Battery Bank

Victoria, University of

33

Data Tools & Models - Time Series - U.S. Energy Information Administration  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsruc DocumentationP-Series to UserProduct: CrudeOffice ofINL is aID Service First DOI

34

Non-homogeneous hidden Markov-switching models for wind time series  

E-Print Network [OSTI]

of wind direction in [27]. However HMMs assume that the successive observations are conditionally conditions at successive time steps for the dataset considered in this work. Markov-Switching Auto

Brest, Université de

35

Time series analysis of regional climate model performance Jason P. Evans  

E-Print Network [OSTI]

in Kansas, United States, including the First International Satellite Land Surface Climatology Project, both regional and global, has become apparent. Predictions of the energy and water balance to evapotranspiration and fails to close the energy budget. All of the models overestimate runoff and evapotranspiration

Evans, Jason

36

Binary versus non-binary information in real time series: empirical results and maximum-entropy matrix models  

E-Print Network [OSTI]

The dynamics of complex systems, from financial markets to the brain, can be monitored in terms of time series of activity of their fundamental elements (such as stocks or neurons respectively). While the main focus of time series analysis is on the magnitude of temporal increments, a significant piece of information is encoded into the binary projection (i.e. the sign) of such increments. In this paper we provide further evidence of this by showing strong nonlinear relationships between binary and non-binary properties of financial time series. We then introduce an information-theoretic approach to the analysis of the binary signature of single and multiple time series. Through the definition of maximum-entropy ensembles of binary matrices, we quantify the information encoded into the simplest binary properties of real time series and identify the most informative property given a set of measurements. Our formalism is able to replicate the observed binary/non-binary relations very well, and to mathematically...

Almog, Assaf

2014-01-01T23:59:59.000Z

37

Exact Primitives for Time Series Data Mining  

E-Print Network [OSTI]

142 Sony AIBO Robot: Surfacetrajectories and ac- celerometer signals from SONY AIBOclasses of time series from the SONY AIBO accelerometer. (b)

Mueen, Abdullah Al

2012-01-01T23:59:59.000Z

38

E-Print Network 3.0 - analyzing time-series gene Sample Search...  

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

series in terms of number... gene networks from time series include boolean network models, 5 Correlation Metric Construction, 6... - constructed time ... Source: D'haeseleer,...

39

Normalizing the causality between time series  

E-Print Network [OSTI]

Recently, a rigorous yet concise formula has been derived to evaluate the information flow, and hence the causality in a quantitative sense, between time series. To assess the importance of a resulting causality, it needs to be normalized. The normalization is achieved through distinguishing three types of fundamental mechanisms that govern the marginal entropy change of the flow recipient. A normalized or relative flow measures its importance relative to other mechanisms. In analyzing realistic series, both absolute and relative information flows need to be taken into account, since the normalizers for a pair of reverse flows belong to two different entropy balances; it is quite normal that two identical flows may differ a lot in relative importance in their respective balances. We have reproduced these results with several autoregressive models. We have also shown applications to a climate change problem and a financial analysis problem. For the former, reconfirmed is the role of the Indian Ocean Dipole as ...

Liang, X San

2015-01-01T23:59:59.000Z

40

Time Series Analysis James D. Hamilton  

E-Print Network [OSTI]

Time Series Analysis James D. Hamilton Since its publication just over ten years ago, James Hamilton's Time Series Analysis has taken its place in the canon of modern technical eco- nomic literature study, Hamilton's book en- joyed popularity among econometricians in seminars in Europe and North

Landweber, Laura

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


41

14.384 Time Series Analysis, Fall 2008  

E-Print Network [OSTI]

The course provides a survey of the theory and application of time series methods in econometrics. Topics covered will include univariate stationary and non-stationary models, vector autoregressions, frequency domain ...

Schrimpf, Paul

42

Turbulencelike Behavior of Seismic Time Series  

SciTech Connect (OSTI)

We report on a stochastic analysis of Earth's vertical velocity time series by using methods originally developed for complex hierarchical systems and, in particular, for turbulent flows. Analysis of the fluctuations of the detrended increments of the series reveals a pronounced transition in their probability density function from Gaussian to non-Gaussian. The transition occurs 5-10 hours prior to a moderate or large earthquake, hence representing a new and reliable precursor for detecting such earthquakes.

Manshour, P.; Saberi, S. [Department of Physics, Sharif University of Technology, Tehran 11155-9161 (Iran, Islamic Republic of); Sahimi, Muhammad [Mork Family Department of Chemical Engineering and Materials Science, University of Southern California, Los Angeles, California 90089-1211 (United States); Peinke, J. [Institute of Physics, Carl von Ossietzky University, D-26111 Oldenburg (Germany); Pacheco, Amalio F. [Department of Theoretical Physics, University of Zaragoza, Pedro Cerbuna 12, 50009 Zaragoza (Spain); Rahimi Tabar, M. Reza [Department of Physics, Sharif University of Technology, Tehran 11155-9161 (Iran, Islamic Republic of); Institute of Physics, Carl von Ossietzky University, D-26111 Oldenburg (Germany); CNRS UMR 6202, Observatoire de la Cote d'Azur, BP 4229, 06304 Nice Cedex 4 (France)

2009-01-09T23:59:59.000Z

43

Integrated method for chaotic time series analysis  

DOE Patents [OSTI]

Methods and apparatus for automatically detecting differences between similar but different states in a nonlinear process monitor nonlinear data are disclosed. Steps include: acquiring the data; digitizing the data; obtaining nonlinear measures of the data via chaotic time series analysis; obtaining time serial trends in the nonlinear measures; and determining by comparison whether differences between similar but different states are indicated. 8 figs.

Hively, L.M.; Ng, E.G.

1998-09-29T23:59:59.000Z

44

Integrated method for chaotic time series analysis  

DOE Patents [OSTI]

Methods and apparatus for automatically detecting differences between similar but different states in a nonlinear process monitor nonlinear data. Steps include: acquiring the data; digitizing the data; obtaining nonlinear measures of the data via chaotic time series analysis; obtaining time serial trends in the nonlinear measures; and determining by comparison whether differences between similar but different states are indicated.

Hively, Lee M. (Philadelphia, TN); Ng, Esmond G. (Concord, TN)

1998-01-01T23:59:59.000Z

45

Can biomass time series be reliably assessed from CPUE time series data Francis Lalo1  

E-Print Network [OSTI]

1 Can biomass time series be reliably assessed from CPUE time series data only? Francis Laloë1 to abundance. This means (i) that catchability is constant and (ii) that all the biomass is catchable. If so, relative variations in CPUE indicate the same relative variations in biomass. Myers and Worm consider

Hawai'i at Manoa, University of

46

Local prediction of turning points of oscillating time series  

E-Print Network [OSTI]

For oscillating time series, the prediction is often focused on the turning points. In order to predict the turning point magnitudes and times it is proposed to form the state space reconstruction only from the turning points and modify the local (nearest neighbor) model accordingly. The model on turning points gives optimal prediction at a lower dimensional state space than the optimal local model applied directly on the oscillating time series and is thus computationally more efficient. Monte Carlo simulations on different oscillating nonlinear systems showed that it gives better predictions of turning points and this is confirmed also for the time series of annual sunspots and total stress in a plastic deformation experiment.

D. Kugiumtzis

2008-08-06T23:59:59.000Z

47

Bayesian analysis of GARCH and stochastic volatility: modeling leverage, jumps and heavy-tails for financial time series  

E-Print Network [OSTI]

Bayesian analysis of GARCH and stochastic volatility: modeling leverage, jumps and heavy for two broad major classes of varying volatility model, GARCH and stochastic volatility (SV) models-t errors yields the best performance among the competing models on the return data. Key words: GARCH, Heavy

Wolpert, Robert L

48

A combined method to estimate parameters of the thalamocortical model from a heavily noise-corrupted time series of action potential  

SciTech Connect (OSTI)

A combined method composing of the unscented Kalman filter (UKF) and the synchronization-based method is proposed for estimating electrophysiological variables and parameters of a thalamocortical (TC) neuron model, which is commonly used for studying Parkinson's disease for its relay role of connecting the basal ganglia and the cortex. In this work, we take into account the condition when only the time series of action potential with heavy noise are available. Numerical results demonstrate that not only this method can estimate model parameters from the extracted time series of action potential successfully but also the effect of its estimation is much better than the only use of the UKF or synchronization-based method, with a higher accuracy and a better robustness against noise, especially under the severe noise conditions. Considering the rather important role of TC neuron in the normal and pathological brain functions, the exploration of the method to estimate the critical parameters could have important implications for the study of its nonlinear dynamics and further treatment of Parkinson's disease.

Wang, Ruofan; Wang, Jiang; Deng, Bin, E-mail: dengbin@tju.edu.cn; Liu, Chen; Wei, Xile [Department of Electrical and Automation Engineering, Tianjin University, Tianjin (China)] [Department of Electrical and Automation Engineering, Tianjin University, Tianjin (China); Tsang, K. M.; Chan, W. L. [Department of Electrical Engineering, The Hong Kong Polytechnic University, Kowloon (Hong Kong)] [Department of Electrical Engineering, The Hong Kong Polytechnic University, Kowloon (Hong Kong)

2014-03-15T23:59:59.000Z

49

QUASI--MAXIMUM--LIKELIHOOD ESTIMATION IN HETEROSCEDASTIC TIME SERIES: A STOCHASTIC RECURRENCE EQUATIONS APPROACH  

E-Print Network [OSTI]

. The resulting theory is applied to popular financial time series models: GARCH(1, 1), asymmetric GARCH(1, 1 for a general class of heteroscedastic time series models, which includes GARCH(1, 1). Recall that the time series (X t ) is called a GARCH(p, q) (generalized autoregressive conditionally heteroscedastic) process

Mikosch, Thomas

50

Improving predictability of time series using maximum entropy methods  

E-Print Network [OSTI]

We discuss how maximum entropy methods may be applied to the reconstruction of Markov processes underlying empirical time series and compare this approach to usual frequency sampling. It is shown that, at least in low dimension, there exists a subset of the space of stochastic matrices for which the MaxEnt method is more efficient than sampling, in the sense that shorter historical samples have to be considered to reach the same accuracy. Considering short samples is of particular interest when modelling smoothly non-stationary processes, for then it provides, under some conditions, a powerful forecasting tool. The method is illustrated for a discretized empirical series of exchange rates.

Gregor Chliamovitch; Alexandre Dupuis; Bastien Chopard; Anton Golub

2014-11-28T23:59:59.000Z

51

Improving predictability of time series using maximum entropy methods  

E-Print Network [OSTI]

We discuss how maximum entropy methods may be applied to the reconstruction of Markov processes underlying empirical time series and compare this approach to usual frequency sampling. It is shown that, at least in low dimension, there exists a subset of the space of stochastic matrices for which the MaxEnt method is more efficient than sampling, in the sense that shorter historical samples have to be considered to reach the same accuracy. Considering short samples is of particular interest when modelling smoothly non-stationary processes, for then it provides, under some conditions, a powerful forecasting tool. The method is illustrated for a discretized empirical series of exchange rates.

Chliamovitch, Gregor; Chopard, Bastien; Golub, Anton

2014-01-01T23:59:59.000Z

52

Shiqing Ling Time-Series Econometric Theory  

E-Print Network [OSTI]

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 2.4 GARCH Models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 3.3 GARCH(1, 1) Models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63 5.3 LAN of FARIMA-GARCH Models . . . . . . . . . . . . . . . . . . . . . . . . . . . 67 5

Ling, Shiqing

53

Forecasting the underlying potential governing climatic time series  

E-Print Network [OSTI]

We introduce a technique of time series analysis, potential forecasting, which is based on dynamical propagation of the probability density of time series. We employ polynomial coefficients of the orthogonal approximation of the empirical probability distribution and extrapolate them in order to forecast the future probability distribution of data. The method is tested on artificial data, used for hindcasting observed climate data, and then applied to forecast Arctic sea-ice time series. The proposed methodology completes a framework for `potential analysis' of climatic tipping points which altogether serves anticipating, detecting and forecasting climate transitions and bifurcations using several independent techniques of time series analysis.

Livina, V N; Mudelsee, M; Lenton, T M

2012-01-01T23:59:59.000Z

54

State Space Reconstruction for Multivariate Time Series Prediction  

E-Print Network [OSTI]

In the nonlinear prediction of scalar time series, the common practice is to reconstruct the state space using time-delay embedding and apply a local model on neighborhoods of the reconstructed space. The method of false nearest neighbors is often used to estimate the embedding dimension. For prediction purposes, the optimal embedding dimension can also be estimated by some prediction error minimization criterion. We investigate the proper state space reconstruction for multivariate time series and modify the two abovementioned criteria to search for optimal embedding in the set of the variables and their delays. We pinpoint the problems that can arise in each case and compare the state space reconstructions (suggested by each of the two methods) on the predictive ability of the local model that uses each of them. Results obtained from Monte Carlo simulations on known chaotic maps revealed the non-uniqueness of optimum reconstruction in the multivariate case and showed that prediction criteria perform better when the task is prediction.

I. Vlachos; D. Kugiumtzis

2008-09-12T23:59:59.000Z

55

Distribution Based Data Filtering for Financial Time Series Forecasting  

E-Print Network [OSTI]

recent past. In this paper, we address the challenge of forecasting the behavior of time series using@unimelb.edu.au Abstract. Changes in the distribution of financial time series, particularly stock market prices, can of stock prices, which aims to forecast the future values of the price of a stock, in order to obtain

Bailey, James

56

APPARENT WATER OPTICAL PROPERTIES AT THE CARIBBEAN TIME SERIES STATION  

E-Print Network [OSTI]

APPARENT WATER OPTICAL PROPERTIES AT THE CARIBBEAN TIME SERIES STATION Roy A. Armstrong, Jose M of Puerto Rico Mayagüez, Puerto Rico 00681 ABSTRACT The Caribbean Time Series, located 28 nautical miles in near- surface waters of the northeastern Caribbean Basin. Apparent optical properties such as, remote

Gilbes, Fernando

57

IMPROVEMENTS TO THE RADIANT TIME SERIES METHOD COOLING LOAD CALCULATION  

E-Print Network [OSTI]

IMPROVEMENTS TO THE RADIANT TIME SERIES METHOD COOLING LOAD CALCULATION PROCEDURE By BEREKET, Australia 1998 Submitted to the Faculty of the Graduate College of the Oklahoma State University in partial TO THE RADIANT TIME SERIES METHOD COOLING LOAD CALCULATION PROCEDURE Dissertation Approved: Dr. Jeffrey D

58

Autoregressive Time Series Forecasting of Computational Demand  

E-Print Network [OSTI]

We study the predictive power of autoregressive moving average models when forecasting demand in two shared computational networks, PlanetLab and Tycoon. Demand in these networks is very volatile, and predictive techniques to plan usage in advance can improve the performance obtained drastically. Our key finding is that a random walk predictor performs best for one-step-ahead forecasts, whereas ARIMA(1,1,0) and adaptive exponential smoothing models perform better for two and three-step-ahead forecasts. A Monte Carlo bootstrap test is proposed to evaluate the continuous prediction performance of different models with arbitrary confidence and statistical significance levels. Although the prediction results differ between the Tycoon and PlanetLab networks, we observe very similar overall statistical properties, such as volatility dynamics.

Sandholm, Thomas

2007-01-01T23:59:59.000Z

59

A Multivariate Time Series Method for Monte Carlo Reactor Analysis  

SciTech Connect (OSTI)

A robust multivariate time series method has been established for the Monte Carlo calculation of neutron multiplication problems. The method is termed Coarse Mesh Projection Method (CMPM) and can be implemented using the coarse statistical bins for acquisition of nuclear fission source data. A novel aspect of CMPM is the combination of the general technical principle of projection pursuit in the signal processing discipline and the neutron multiplication eigenvalue problem in the nuclear engineering discipline. CMPM enables reactor physicists to accurately evaluate major eigenvalue separations of nuclear reactors with continuous energy Monte Carlo calculation. CMPM was incorporated in the MCNP Monte Carlo particle transport code of Los Alamos National Laboratory. The great advantage of CMPM over the traditional Fission Matrix method is demonstrated for the three space-dimensional modeling of the initial core of a pressurized water reactor.

Taro Ueki

2008-08-14T23:59:59.000Z

60

Continuous Time Random Walks and South Spain Seismic Series  

E-Print Network [OSTI]

Levy flights were introduced through the mathematical research of the algebra or random variables with infinite moments. Mandelbrot recognized that the Levy flight prescription had a deep connection to scale-invariant fractal random walk trajectories. The theory of Continuous Time Random Walks (CTRW) can be described in terms of Levy distribution functions and it can be used to explain some earthquake characteristics like the distribution of waiting times and hypocenter locations in a seismic region. This paper checks the validity of this assumption analyzing three seismic series localized in South Spain. The three seismic series (Alboran, Antequera and Loja) show qualitatively the same behavior, although there are quantitative differences between them.

A. Posadas; J. Morales; F. Vidal; O. Sotolongo-Costa; J. C. Antoranz

2002-05-27T23:59:59.000Z

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


61

Linear and nonlinear time series analysis of the black hole candidate Cygnus X-1  

E-Print Network [OSTI]

We analyze the variability in the X-ray lightcurves of the black hole candidate Cygnus X-1 by linear and nonlinear time series analysis methods. While a linear model describes the over-all second order properties of the observed data well, surrogate data analysis reveals a significant deviation from linearity. We discuss the relation between shot noise models usually applied to analyze these data and linear stochastic autoregressive models. We debate statistical and interpretational issues of surrogate data testing for the present context. Finally, we suggest a combination of tools from linear andnonlinear time series analysis methods as a procedure to test the predictions of astrophysical models on observed data.

J. Timmer; U. Schwarz; H. U. Voss; I. Wardinski; T. Belloni; G. Hasinger; M. van der Klis; Juergen Kurths

1999-11-10T23:59:59.000Z

62

Trade and Income Exploiting Time Series in James Feyrer  

E-Print Network [OSTI]

Trade and Income ­ Exploiting Time Series in Geography James Feyrer Dartmouth College October 23. Rodriguez and Rodrik (2000) show that these results are not robust to controlling for omitted variables conferences for helpful comments. All errors are my own. james.feyrer@dartmouth.edu, Dartmouth College

Lotko, William

63

CONSISTENT FUNCTIONAL PCA FOR FINANCIAL TIME-SERIES Sebastian Jaimungal  

E-Print Network [OSTI]

of Figure 1 we present a time-series resulting from the NYMEX light sweet crude oil futures price data set sweet crude oil futures curves and demonstrate that it contains significant advan- tages over FPCA as opposed to a modification of the usual PCA is quite simple: futures price data on a given day

Jaimungal, Sebastian

64

Visual Analysis of Frequent Patterns In Large Time Series  

E-Print Network [OSTI]

1 shows an example on how to monitor chiller efficiency in data centers using a pair of data center chiller time series in which different motifs were discovered. The illustrated process can be subdivided valued vector ti captures the data values (e.g., chiller utilization in the data center example), we

Ramakrishnan, Naren

65

Time series of a CME blasting out from the Sun  

E-Print Network [OSTI]

#12;Time series of a CME blasting out from the Sun Composite image of the Sun in UV light with the naked eye, the Sun seems static, placid, constant. From the ground, the only notice- able variations in the Sun are its location (where will it rise and set today?) and its color (will clouds cover

Christian, Eric

66

Estimating the predictability of economic and financial time series  

E-Print Network [OSTI]

The predictability of a time series is determined by the sensitivity to initial conditions of its data generating process. In this paper our goal is to characterize this sensitivity from a finite sample by assuming few hypotheses on the data generating model structure. In order to measure the distance between two trajectories induced by a same noisy chaotic dynamic from two close initial conditions, a symmetric Kullback-Leiber divergence measure is used. Our approach allows to take into account the dependence of the residual variance on initial conditions. We show it is linked to a Fisher information matrix and we investigated its expressions in the cases of covariance-stationary processes and ARCH($\\infty$) processes. Moreover, we propose a consistent non-parametric estimator of this sensitivity matrix in the case of conditionally heteroscedastic autoregressive nonlinear processes. Various statistical hypotheses can so be tested as for instance the hypothesis that the data generating process is "almost" independently distributed at a given moment. Applications to simulated data and to the stock market index S&P500 illustrate our findings. More particularly, we highlight a significant relationship between the sensitivity to initial conditions of the daily returns of the S&P 500 and their volatility.

Quentin Giai Gianetto; Jean-Marc Le Caillec; Erwan Marrec

2012-12-12T23:59:59.000Z

67

De Bilt, 2012 | Technical Report ; TR-326 Time series transformation tool  

E-Print Network [OSTI]

De Bilt, 2012 | Technical Report ; TR-326 Time series transformation tool: description #12;#12;Time series transformation tool: description of the program to generate time series consistent ransformation tool: description of the program to generate time series consistent with the KNMI'06 climate

Stoffelen, Ad

68

arXiv:physics/0612221v1[physics.data-an]22Dec2006 APS/123-QED Characterizing and modeling cyclic behavior in non-stationary time series through  

E-Print Network [OSTI]

@prl.res.in these time series using random matrix theory. In partic- ular, analysis of the cross-correlations between behavior between stocks of different companies. This behavior can manifest in the composite stock price

Fernandez, Thomas

69

Some applications of wavelets to time series data  

E-Print Network [OSTI]

stationary time series {Xt} is said to have long memory when long memory parameter d is between 0 and 0.5. Many methods of estimating long memory parameter based on its decay rate of autocorrelation or behavior of spectral density around zero have been....For consistency, some people consider the original dataXt asv0,t. Due to decimating property, we haveN/2j wavelet and scaling coefficients at levelj. The constraint on sample size, N = 2J can be relaxed by considering partial discrete wavelet transform. 2...

Jeong, Jae Sik

2009-05-15T23:59:59.000Z

70

Time series analysis and long range correlations of Nordic spot electricity market  

E-Print Network [OSTI]

, 21020 Ispra(VA), Italy Abstract The electricity system price of the Nord Pool spot market is analysed. Weron and Przybylowicz [19] studied the electricity prices using Hurst R/S analysis and showed anti energy spot price time series. The question of modelling electricity spot prices has also been addressed

Wright, Francis

71

Intervention adjustment to data of the joint petroleum reporting system. [1976 to 1983 time series; USA  

SciTech Connect (OSTI)

This report deals specifically with changes made to the survey forms in January 1981 and the resulting changes to the data-time series. Naturally, when a series has changed at some time point, the data after the change are no longer comparable to those before. In many cases, though, comparisons are desired that use pre- and post-intervention data as a series. It is thus necessary to have a methodology for updating the older data so that such comparisons can be made validly. To produce this methodology, the particular intervention must be modeled. However, when attempting to analyze one particular intervention, other types of interventions must be considered also. If effects of the other interventions can be modeled, the overall variability of the series can be reduced and the intervention of interest can be better isolated. Thus, in the following, we discuss (in addition to the format modifications of the forms) the trends and changes noted in the JPRS since January 1976 to December 1982. The year 1976 was chosen since it corresponds to the first year for which microdata are computerized in a universal format in the JPRS master files. We discuss, in particular, changes to the data series for inventories of: (a) motor gasoline, (b) distillate oil, (c) residual fuel oil, and (d) crude oil. These are the series studied in detail in subsequent sections of this report.

Hall, D.L.; Gardenier, T.K.; Slavich, A.L.

1984-10-01T23:59:59.000Z

72

Characterizing system dynamics with a weighted and directed network constructed from time series data  

SciTech Connect (OSTI)

In this work, we propose a novel method to transform a time series into a weighted and directed network. For a given time series, we first generate a set of segments via a sliding window, and then use a doubly symbolic scheme to characterize every windowed segment by combining absolute amplitude information with an ordinal pattern characterization. Based on this construction, a network can be directly constructed from the given time series: segments corresponding to different symbol-pairs are mapped to network nodes and the temporal succession between nodes is represented by directed links. With this conversion, dynamics underlying the time series has been encoded into the network structure. We illustrate the potential of our networks with a well-studied dynamical model as a benchmark example. Results show that network measures for characterizing global properties can detect the dynamical transitions in the underlying system. Moreover, we employ a random walk algorithm to sample loops in our networks, and find that time series with different dynamics exhibits distinct cycle structure. That is, the relative prevalence of loops with different lengths can be used to identify the underlying dynamics.

Sun, Xiaoran, E-mail: sxr0806@gmail.com [Shenzhen Graduate School, Harbin Institute of Technology, Shenzhen 518055 (China) [Shenzhen Graduate School, Harbin Institute of Technology, Shenzhen 518055 (China); School of Mathematics and Statistics, The University of Western Australia, Crawley WA 6009 (Australia); Small, Michael, E-mail: michael.small@uwa.edu.au [School of Mathematics and Statistics, The University of Western Australia, Crawley WA 6009 (Australia)] [School of Mathematics and Statistics, The University of Western Australia, Crawley WA 6009 (Australia); Zhao, Yi [Shenzhen Graduate School, Harbin Institute of Technology, Shenzhen 518055 (China)] [Shenzhen Graduate School, Harbin Institute of Technology, Shenzhen 518055 (China); Xue, Xiaoping [Department of Mathematics, Harbin Institute of Technology, Harbin 150025 (China)] [Department of Mathematics, Harbin Institute of Technology, Harbin 150025 (China)

2014-06-15T23:59:59.000Z

73

Cliometrics and Time Series Econometrics: Some Theory and Applications  

E-Print Network [OSTI]

. Applications include a discussion of the timing and potential causes of the British Industrial Revolution, convergence, long memory, graphical modelling, British Industrial Revolution. JEL classifications N33, O47, O

Hickman, Mark

74

Time series power flow analysis for distribution connected PV generation.  

SciTech Connect (OSTI)

Distributed photovoltaic (PV) projects must go through an interconnection study process before connecting to the distribution grid. These studies are intended to identify the likely impacts and mitigation alternatives. In the majority of the cases, system impacts can be ruled out or mitigation can be identified without an involved study, through a screening process or a simple supplemental review study. For some proposed projects, expensive and time-consuming interconnection studies are required. The challenges to performing the studies are twofold. First, every study scenario is potentially unique, as the studies are often highly specific to the amount of PV generation capacity that varies greatly from feeder to feeder and is often unevenly distributed along the same feeder. This can cause location-specific impacts and mitigations. The second challenge is the inherent variability in PV power output which can interact with feeder operation in complex ways, by affecting the operation of voltage regulation and protection devices. The typical simulation tools and methods in use today for distribution system planning are often not adequate to accurately assess these potential impacts. This report demonstrates how quasi-static time series (QSTS) simulation and high time-resolution data can be used to assess the potential impacts in a more comprehensive manner. The QSTS simulations are applied to a set of sample feeders with high PV deployment to illustrate the usefulness of the approach. The report describes methods that can help determine how PV affects distribution system operations. The simulation results are focused on enhancing the understanding of the underlying technical issues. The examples also highlight the steps needed to perform QSTS simulation and describe the data needed to drive the simulations. The goal of this report is to make the methodology of time series power flow analysis readily accessible to utilities and others responsible for evaluating potential PV impacts.

Broderick, Robert Joseph; Quiroz, Jimmy Edward; Ellis, Abraham; Reno, Matthew J. [Georgia Institute of Technology, Atlanta, GA; Smith, Jeff [Electric Power Research Institute, Knoxville, TN; Dugan, Roger [Electric Power Research Institute, Knoxville, TN

2013-01-01T23:59:59.000Z

75

Wind Speed Prediction Via Time Series Modeling.  

E-Print Network [OSTI]

??Projected construction of nearby wind farms motivates this study of statistical forecasting of wind speed, for which accurate prediction is critically important to the fluid… (more)

Alexander, Daniel

2009-01-01T23:59:59.000Z

76

Merging Multiple-Partial-Depth Data Time Series Using Objective Empirical Orthogonal Function Fitting  

E-Print Network [OSTI]

In this paper, a method for merging partial overlapping time series of ocean profiles into a single time series of profiles using empirical orthogonal function (EOF) decomposition with the objective analysis is presented. ...

Lin, Ying-Tsong

77

A time-series approach to dynamical systems from classical and quantum worlds  

SciTech Connect (OSTI)

This contribution discusses some recent applications of time-series analysis in Random Matrix Theory (RMT), and applications of RMT in the statistial analysis of eigenspectra of correlation matrices of multivariate time series.

Fossion, Ruben [Instituto Nacional de Geriatría, Periférico Sur No. 2767, Col. San Jerónimo Lídice, Del. Magdalena Contreras, 10200 México D.F., Mexico and Centro de Ciencias de la Complejidad (C3), Universidad Nacional Autó (Mexico)

2014-01-08T23:59:59.000Z

78

Filtering out high frequencies in time series using F-transform$  

E-Print Network [OSTI]

Filtering out high frequencies in time series using F-transform$ Vil´em Nov´akc , Irina Perfilievac) Preprint submitted to Elsevier February 10, 2013 #12;Filtering out high frequencies in time series using F at El Paso 500 W. University, El Paso, TX 79968, USA This paper is devoted to analysis of time series

Kreinovich, Vladik

79

Filtering out high frequencies in time series using F-transform$  

E-Print Network [OSTI]

Filtering out high frequencies in time series using F-transform$ Vil´em Nov´akc , Irina Perfilievac) Preprint submitted to Elsevier February 3, 2014 #12;Filtering out high frequencies in time series using F, El Paso, TX 79968, USA 1. Introduction This paper is devoted to analysis of time series using fuzzy

Kreinovich, Vladik

80

Geospatial analysis of vulnerable beach-foredune systems from decadal time series of lidar data  

E-Print Network [OSTI]

Geospatial analysis of vulnerable beach-foredune systems from decadal time series of lidar data, Geospatial analysis of vulnerable beach- foredune systems from decadal time series of lidar data, Journal densities; therefore, geospatial analysis, when applied to decadal lidar time series, needs to address

Mitasova, Helena

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


81

Exposure Measurement Error in Time-Series Studies of Air Pollution: Concepts and Consequences  

E-Print Network [OSTI]

of air pollution and health. Because measurement error may have substantial implications for interpreting1 Exposure Measurement Error in Time-Series Studies of Air Pollution: Concepts and Consequences S in time-series studies 1 11/11/99 Keywords: measurement error, air pollution, time series, exposure

Dominici, Francesca

82

Essays on Bayesian Time Series and Variable Selection  

E-Print Network [OSTI]

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69 vi LIST OF FIGURES FIGURE Page 2.1 Dynamic Model. Given xt, yt is independent of y1:t?1, x1:t?1. . . . . . . 7 2.2 The figure shows estimated value of ? and ?2 from : (a)-(b) Stochastic Approximation approach; (c)-(d) Augmentation approach. In each... Sorenson (1970). 6 Let yt and xt be the p and q dimensional observation and hidden state variable at the time t. Let ? be set of unknown parameter. Figure (2.1) depicts the dynamic relation between yt and xt. The generalized version of state-space model can...

De, Debkumar

2014-05-08T23:59:59.000Z

83

Detecting and interpreting distortions in hierarchical organization of complex time series  

E-Print Network [OSTI]

Hierarchical organization is a cornerstone of complexity and multifractality constitutes its central quantifying concept. For model uniform cascades the corresponding singularity spectra are symmetric while those extracted from empirical data are often asymmetric. Using the selected time series representing such diverse phenomena like price changes and inter-transaction times in the financial markets, sentence length variability in the narrative texts, Missouri River discharge and Sunspot Number variability as examples, we show that the resulting singularity spectra appear strongly asymmetric, more often left-sided but in some cases also right-sided. We present a unified view on the origin of such effects and indicate that they may be crucially informative for identifying composition of the time series. One particularly intriguing case of this later kind of asymmetry is detected in the daily reported Sunspot Number variability. This signals that either the commonly used famous Wolf formula distorts the real d...

Dro?d?, Stanis?aw

2015-01-01T23:59:59.000Z

84

SumTime-Turbine: A Knowledge-Based System to Communicate Gas Turbine Time-Series Data  

E-Print Network [OSTI]

SumTime-Turbine: A Knowledge-Based System to Communicate Gas Turbine Time-Series Data Jin Yu of Aberdeen Aberdeen, AB24 3UE, UK {jyu, ereiter, jhunter, ssripada}@csd.abdn.ac.uk Abstract: SumTime-Turbine produces textual summaries of archived time- series data from gas turbines. These summaries should help

Reiter, Ehud

85

Separation of Stochastic and Deterministic Information from Seismological Time Series with Nonlinear Dynamics and Maximum Entropy Methods  

SciTech Connect (OSTI)

We present a procedure developed to detect stochastic and deterministic information contained in empirical time series, useful to characterize and make models of different aspects of complex phenomena represented by such data. This procedure is applied to a seismological time series to obtain new information to study and understand geological phenomena. We use concepts and methods from nonlinear dynamics and maximum entropy. The mentioned method allows an optimal analysis of the available information.

Gutierrez, Rafael M.; Useche, Gina M.; Buitrago, Elias [Centro de Investigaciones, Universidad Antonio Narino, Carrera 3 Este No. 47A--15 Bogota (Colombia)

2007-11-13T23:59:59.000Z

86

E-Print Network 3.0 - ad-hoc time series Sample Search Results  

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

series Search Powered by Explorit Topic List Advanced Search Sample search results for: ad-hoc time series Page: << < 1 2 3 4 5 > >> 1 International Journal of Information...

87

The level crossing analysis of German stock market index (DAX) and daily oil price time series  

E-Print Network [OSTI]

The level crossing analysis of DAX and oil price time series are given. We determine the average frequency of positive-slope crossings, $\

Shayeganfar, F; Peinke, J; Tabar, M Reza Rahimi

2010-01-01T23:59:59.000Z

88

Resampling Methodology in Spatial Prediction and Repeated Measures Time Series  

E-Print Network [OSTI]

procedure can also be used to produce prediction intervals. When 18 the Y (?) process is Gaussian, these prediction intervals should perform no better than the interval in (D.14). However, when working with real world data, the assumptions of a Gaussian...- series representation given by ?(x) = ?? k=0 dk(x? ?(s0))k, x ? R (E.19) for some d0, d1, . . . ? R. Further, supppose that E [ Z?n(s0) ]2 = O(1) and that for some k1 ? (0,?), ?? k=1 ?? j=1 kj|dkdj|2 (k+j?2)/2? ( k + j ? 1 2 )[ ?j+k?2...

Rister, Krista Dianne

2012-02-14T23:59:59.000Z

89

Inverting geodetic time series with a principal component analysis-based inversion method  

E-Print Network [OSTI]

Inverting geodetic time series with a principal component analysis-based inversion method A. P (2010), Inverting geodetic time series with a principal component analysis-based inversion method, J; Cohen, 1999]. This formulation is linear and easily inverted using standard algorithms. The distribution

Avouac, Jean-Philippe

90

TQuEST: Threshold Query Execution for Large Sets of Time Series  

E-Print Network [OSTI]

. environmental air pollution which has gained rapidly increasing attention by many European research projects million time series, each representing the daily course of air pollution parameters1 . It is important data mining in time series databases is essential in many application domains as for instance

Kriegel, Hans-Peter

91

DETERMINING THE FRACTAL DIMENSION OF A TIME SERIES WITH A NEURAL NET  

E-Print Network [OSTI]

DETERMINING THE FRACTAL DIMENSION OF A TIME SERIES WITH A NEURAL NET MARK J. EMBRECHTS AND YARON and require expert interaction for interpreting the calculated fractal dimension. Artificial neural nets (ANN) offer a fast and elegant way to estimate the fractal dimension of a time series. A backpropagation net

Danon, Yaron

92

A test for second order stationarity of a time series based on the Discrete Fourier Transform  

E-Print Network [OSTI]

A test for second order stationarity of a time series based on the Discrete Fourier Transform property, we construct a Portmanteau type test statistic for testing stationarity of the time series. It is shown that under the null of stationarity, the test statistic is approximately a chi square distribution

Subba Rao, Suhasini

93

OBST-based segmentation approach to financial time series Yain-Whar Si n  

E-Print Network [OSTI]

applications. Examples of time series include historical price and trading volume obtained from financial stock' judgment. In technical analysis, time series data such as historical price, volume, and other statistical the movement of the price. Analysts may also take into account other factors such as government policies

Si, Yain Whar "Lawrence"

94

New Problems for an Old Design: Time-Series Analyses of Air Pollution and Health  

E-Print Network [OSTI]

New Problems for an Old Design: Time-Series Analyses of Air Pollution and Health Jonathan M. Samet1 for adverse effects of particulate air pollution on the public's health. The daily time-series studies of air to public health posed by air pollution, tending to provide risk coefficients that are biased upwards

Dominici, Francesca

95

Detecting Climate Change in Multivariate Time Series Data by Novel Clustering and Cluster Tracing Techniques  

E-Print Network [OSTI]

Detecting Climate Change in Multivariate Time Series Data by Novel Clustering and Cluster Tracing Aachen University, Germany {kremer, guennemann, seidl}@cs.rwth-aachen.de Abstract--Climate change can series, and trace the clusters over time. A climate pattern is categorized as a changing pattern

96

Lean Blow-Out Prediction in Gas Turbine Combustors Using Symbolic Time Series Analysis  

E-Print Network [OSTI]

Lean Blow-Out Prediction in Gas Turbine Combustors Using Symbolic Time Series Analysis Achintya of lean blowout in gas turbine combustors based on symbolic analysis of time series data from optical. For the purpose of detecting lean blowout in gas turbine combustors, the state probability vector obtained

Ray, Asok

97

Mining Markov chain transition matrix from wind speed time series data Zhe Song a,  

E-Print Network [OSTI]

). Knowing how wind behaves at specific wind farms is extremely important for today's power systems in termsMining Markov chain transition matrix from wind speed time series data Zhe Song a, , Xiulin Geng Wind speed time series Wind power Evolutionary algorithms Markov chain Optimization a b s t r a c

Kusiak, Andrew

98

autoregressive time series: Topics by E-print Network  

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

with several autoregressive models. We have also shown applications to a climate change problem and a financial analysis problem. For the former, reconfirmed is the role of...

99

astronomical time series: Topics by E-print Network  

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

with several autoregressive models. We have also shown applications to a climate change problem and a financial analysis problem. For the former, reconfirmed is the role of...

100

Applications of Time Series in Finance and Macroeconomics  

E-Print Network [OSTI]

with constant intensity. The last essay applies a dynamic factor model to generate out-of-sample forecasts for the inflation rate in Mexico. Factor models are useful to summarize the information contained in large datasets. We evaluate the role of using a wide...

Ibarra Ramirez, Raul

2011-08-08T23:59:59.000Z

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


101

Long-range correlations and trends in Colombian seismic time series  

E-Print Network [OSTI]

We detect long-range correlations and trends in time series extracted from the data of seismic events occurred since 1973 until 2011 in a rectangular region that contain mainly all the continental part of Colombia. The long-range correlations are detected by the calculation of the Hurst exponents for the time series of interevent intervals, separation distances, depth differences and magnitude differences. By using a geometrical modification of the classical R/S method that has been developed to detect long-range correlations in short time series, we find the existence of persistence for all the time series considered. We find also, by using the DFA until the third order, that the time series of interevent intervals, separation distances and depth differences are influenced by quadratic trends, while the time series of magnitude differences is influenced by a linear trend. Finally, for the time series of interevent intervals, we present an analysis of the Hurst exponent as a function of the time and the minim...

Martin-Montoya, L A; Quimbay, C J

2014-01-01T23:59:59.000Z

102

Stochastic Simulation Methods for Precipitation and Streamflow Time Series  

E-Print Network [OSTI]

One major acknowledged challenge in daily precipitation is the inability to model extreme events in the spectrum of events. These extreme events are rare but may cause large losses. How to realistically simulate extreme behavior of daily...

Li, Chao

2013-04-30T23:59:59.000Z

103

V-uniform ergodicity of threshold autoregressive nonlinear time series  

E-Print Network [OSTI]

intervals. Each threshold autoregressive model can be embedded in a Markov chain on Rp. For specifics, if we write Xt = (yt,yt-1,...,yt-p+1)prime the TAR(p) model introduced in (1.1) can be expressed as the following: Xt = AiXt-1 +nut, Xt-1 element Ri (1... ... 0 0 0 1 0 ... 0 ... 0 ... 0 0 0 .. ... 1 0 1 CC CC CC CC CC A 3 and nut = xit(1,0,...,0)prime . Since the distribution of Xt given X0,...,Xt-1 depends upon Xt-1 only, Xt is a Markov chain. The transition measure of Xt is singular w.r.t. Lebesgue...

Boucher, Thomas Richard

2004-09-30T23:59:59.000Z

104

EXPERIMENTAL VALIDATION OF THE RADIANT TIME SERIES METHOD FOR COOLING LOAD  

E-Print Network [OSTI]

EXPERIMENTAL VALIDATION OF THE RADIANT TIME SERIES METHOD FOR COOLING LOAD CALCULATIONS By IP SENG College of the Oklahoma State University in partial fulfillment of the requirements for the Degree LOAD CALCULATIONS Thesis Approved: _______________________________________ Thesis Advisor

105

INCORPORATING NATURAL VARIATION INTO TIME SERIES-BASED LAND COVER CHANGE IDENTIFICATION  

E-Print Network [OSTI]

INCORPORATING NATURAL VARIATION INTO TIME SERIES-BASED LAND COVER CHANGE IDENTIFICATION VARUN in forests. The bulk of work in identifying land cover changes using remote sensing data involves image

Minnesota, University of

106

Using temporal averaging to decouple annual and nonannual information in AVHRR NDVI time series  

E-Print Network [OSTI]

As regularly spaced time series imagery becomes more prevalent in the remote sensing community, monitoring these data for temporal consistency will become an increasingly important problem. Long-term trends must be identified, and it must...

Kastens, Jude Heathcliff; Lerner, David E.; Jakubauskas, Mark E.

2003-11-01T23:59:59.000Z

107

The Spectral Density Estimation of Stationary Time Series with Missing Data  

E-Print Network [OSTI]

reported in literature (see, e.g. Green et al., 2002, Kaneoke and Vitek, 1996, Fortin and Mackey, 1999, and Laguna et al., 1998). Here we consider estimating the spectral density of stationary time series

Schellekens, Michel P.

108

Fractal, entropic and chaotic approaches to complex physiological time series analysis: a critical appraisal  

E-Print Network [OSTI]

A wide variety of methods based on fractal, entropic or chaotic approaches have been applied to the analysis of complex physiological time series. In this paper, we show that fractal and entropy measures are poor indicators ...

Wu, Guo-Qiang

109

Generating English Summaries of Time Series Data Using the Gricean Maxims  

E-Print Network [OSTI]

, gas-turbine sensor readings, and hospital intensive care data. Our weather-forecast generator technology for generating English textual summaries of time-series data, in three domains: weather forecasts

Sripada, Yaji

110

The relation between Brazilian and Chicago Board of Trade soybean prices: a time series test  

E-Print Network [OSTI]

THE RELATION BETWEEN BRAZILIAN AND CHICAGO BOARD OF TRADE SOYBEAN PRICES ? A TIME SERIES TEST A Thesis BRUNO MELCHER Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements... for the degree of MASTER OF SCIENCE May 1991 Major Subject: Agricultural Economics THE RELATION BETWEEN BRAZILIAN AND CHICAGO BOARD OF TRADE SOYBEAN PRICES ? A TIME SERIES TEST A Thesis by BRUNO MELCHER Approved as to style and content by: ' f J David...

Melcher, Bruno

1991-01-01T23:59:59.000Z

111

Validation of Danish wind time series from a new global renewable energy atlas for energy system analysis  

E-Print Network [OSTI]

We present a new global high-resolution renewable energy atlas (REatlas) that can be used to calculate customised hourly time series of wind and solar PV power generation. In this paper, the atlas is applied to produce 32-year-long hourly model wind power time series for Denmark for each historical and future year between 1980 and 2035. These are calibrated and validated against real production data from the period 2000 to 2010. The high number of years allows us to discuss how the characteristics of Danish wind power generation varies between individual weather years. As an example, the annual energy production is found to vary by $\\pm10\\%$ from the average. Furthermore, we show how the production pattern change as small onshore turbines are gradually replaced by large onshore and offshore turbines. In most energy system analysis tools, fixed hourly time series of wind power generation are used to model future power systems with high penetrations of wind energy. Here, we compare the wind power time series fo...

Andresen, Gorm Bruun; Greiner, Martin

2014-01-01T23:59:59.000Z

112

Precursory signatures of protein folding/unfolding: From time series correlation analysis to atomistic mechanisms  

SciTech Connect (OSTI)

Folded conformations of proteins in thermodynamically stable states have long lifetimes. Before it folds into a stable conformation, or after unfolding from a stable conformation, the protein will generally stray from one random conformation to another leading thus to rapid fluctuations. Brief structural changes therefore occur before folding and unfolding events. These short-lived movements are easily overlooked in studies of folding/unfolding for they represent momentary excursions of the protein to explore conformations in the neighborhood of the stable conformation. The present study looks for precursory signatures of protein folding/unfolding within these rapid fluctuations through a combination of three techniques: (1) ultrafast shape recognition, (2) time series segmentation, and (3) time series correlation analysis. The first procedure measures the differences between statistical distance distributions of atoms in different conformations by calculating shape similarity indices from molecular dynamics simulation trajectories. The second procedure is used to discover the times at which the protein makes transitions from one conformation to another. Finally, we employ the third technique to exploit spatial fingerprints of the stable conformations; this procedure is to map out the sequences of changes preceding the actual folding and unfolding events, since strongly correlated atoms in different conformations are different due to bond and steric constraints. The aforementioned high-frequency fluctuations are therefore characterized by distinct correlational and structural changes that are associated with rate-limiting precursors that translate into brief segments. Guided by these technical procedures, we choose a model system, a fragment of the protein transthyretin, for identifying in this system not only the precursory signatures of transitions associated with ? helix and ? hairpin, but also the important role played by weaker correlations in such protein folding dynamics.

Hsu, P. J.; Lai, S. K., E-mail: sklai@coll.phy.ncu.edu.tw [Complex Liquids Laboratory, Department of Physics, National Central University, Chungli 320 Taiwan (China); Molecular Science and Technology Program, Taiwan International Graduate Program, Academia Sinica, Taipei 115, Taiwan (China); Cheong, S. A. [Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore 637371 (Singapore)

2014-05-28T23:59:59.000Z

113

Modeling exchange rate dependence dynamics at different time horizons  

E-Print Network [OSTI]

, Copula-GARCH, Conditional dependence, Dynamic copula Corresponding author. Tel.: +44(0) 247 657 4297. Financial time-series are often modeled with GARCH type models. In the multivariate GARCH literature there exist several models, like CCC- GARCH, DVEC, matrix-diagonal GARCH, BEKK and principal components GARCH

Embrechts, Paul

114

Multiple Alignment of Continuous Time Series Jennifer Listgarten + , Radford M. Neal + , Sam T. Roweis + and Andrew Emili #  

E-Print Network [OSTI]

Multiple Alignment of Continuous Time Series Jennifer Listgarten + , Radford M. Neal + , Sam T of continuous­valued time series from a stochastic process often contain systematic variations in rate time series generated by a noisy, stochastic process, large sys­ tematic sources of variability

Roweis, Sam

115

Documentation of the Hourly Time Series NCEP Climate Forecast System Reanalysis  

E-Print Network [OSTI]

- 1 - Documentation of the Hourly Time Series from the NCEP Climate Forecast System Reanalysis: ------------------------------------------------------------------------------------------------------------ Initial condition 1 Jan 1979, 0Z Record 1: f00: forecast at first time step of 3 mins Record 2: f01: forecast (either averaged over 0 to 1 hour, or instantaneous at 1 hour) Record 3: f02: forecast (either

116

Visualizing Frequent Patterns in Large Multivariate Time Series , M. Marwah1  

E-Print Network [OSTI]

languages, detecting anomalies in patients' medical records over time [5], and chiller efficiency in data centers [14]. Figure 1 shows an example of the visual analysis of a pair of data center chiller time series in which different motifs were discovered. A chiller is a key component of the cooling

Ramakrishnan, Naren

117

Anomaly detection in thermal pulse combustors using symbolic time series analysis  

E-Print Network [OSTI]

339 Anomaly detection in thermal pulse combustors using symbolic time series analysis S Gupta1 for anomaly detection in thermal pulse combustors. The anomaly detection method has been tested on the time pulse combustor. Results are presented to exemplify early detection of combustion instability due

Ray, Asok

118

Melting of small Arctic ice caps observed from ERS scatterometer time series  

E-Print Network [OSTI]

Melting of small Arctic ice caps observed from ERS scatterometer time series Laurence C. Smith,1 of melt onset can be observed over small ice caps, as well as the major ice sheets and multi-year sea ice for 14 small Arctic ice caps from 1992­2000. Interannual and regional variability in the timing of melt

Smith, Laurence C.

119

Forecasting of preprocessed daily solar radiation time series using neural networks  

E-Print Network [OSTI]

Forecasting of preprocessed daily solar radiation time series using neural networks Christophe prediction of global solar radiation on a horizontal surface. First results are promising with nRMSE ~ 21 t or at day d and year y d H0 Extraterrestrial solar radiation coefficient for day d [MJ/m²] xt, xd,y Time

Boyer, Edmond

120

Forecasting of preprocessed daily solar radiation time series using neural networks  

SciTech Connect (OSTI)

In this paper, we present an application of Artificial Neural Networks (ANNs) in the renewable energy domain. We particularly look at the Multi-Layer Perceptron (MLP) network which has been the most used of ANNs architectures both in the renewable energy domain and in the time series forecasting. We have used a MLP and an ad hoc time series pre-processing to develop a methodology for the daily prediction of global solar radiation on a horizontal surface. First results are promising with nRMSE {proportional_to} 21% and RMSE {proportional_to} 3.59 MJ/m{sup 2}. The optimized MLP presents predictions similar to or even better than conventional and reference methods such as ARIMA techniques, Bayesian inference, Markov chains and k-Nearest-Neighbors. Moreover we found that the data pre-processing approach proposed can reduce significantly forecasting errors of about 6% compared to conventional prediction methods such as Markov chains or Bayesian inference. The simulator proposed has been obtained using 19 years of available data from the meteorological station of Ajaccio (Corsica Island, France, 41 55'N, 8 44'E, 4 m above mean sea level). The predicted whole methodology has been validated on a 1.175 kWc mono-Si PV power grid. Six prediction methods (ANN, clear sky model, combination..) allow to predict the best daily DC PV power production at horizon d + 1. The cumulated DC PV energy on a 6-months period shows a great agreement between simulated and measured data (R{sup 2} > 0.99 and nRMSE < 2%). (author)

Paoli, Christophe; Muselli, Marc; Nivet, Marie-Laure [University of Corsica, CNRS UMR SPE, Corte (France); Voyant, Cyril [University of Corsica, CNRS UMR SPE, Corte (France); Hospital of Castelluccio, Radiotherapy Unit, Ajaccio (France)

2010-12-15T23:59:59.000Z

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


121

Devils staircase like behavior of the range of random time series associated with the tangled nature of evolution  

E-Print Network [OSTI]

We present empirical evidence that the range of random time series associated with the tangled nature model of evolution exhibits a devils staircase like behavior characterized by logarithmic trend and the universal multi-affine spectrum of scaling exponents xi_c of q leq q_c moments of q-order height-height correlations, whereas for q > q_c the moments behaves logarithmically.

Balankin, A S; Balankin, Alexander S.

2005-01-01T23:59:59.000Z

122

Nonlinear analysis of time series of vibration data from a friction brake: SSA, PCA, and MFDFA  

E-Print Network [OSTI]

We use the methodology of singular spectrum analysis (SSA), principal component analysis (PCA), and multi-fractal detrended fluctuation analysis (MFDFA), for investigating characteristics of vibration time series data from a friction brake. SSA and PCA are used to study the long time-scale characteristics of the time series. MFDFA is applied for investigating all time scales up to the smallest recorded one. It turns out that the majority of the long time-scale dynamics, that is presumably dominated by the structural dynamics of the brake system, is dominated by very few active dimensions only and can well be understood in terms of low dimensional chaotic attractors. The multi-fractal analysis shows that the fast dynamical processes originating in the friction interface are in turn truly multi-scale in nature.

Nikolay K. Vitanov; Norbert P. Hoffmann; Boris Wernitz

2014-10-23T23:59:59.000Z

123

SEAWIFS VALIDATION AT THE CARIBBEAN TIME SERIES STATION (CATS) Jess Lee-Borges* and Roy Armstrong  

E-Print Network [OSTI]

SEAWIFS VALIDATION AT THE CARIBBEAN TIME SERIES STATION (CATS) Jesús Lee-Borges* and Roy Armstrong. This is of particular importance to areas such as the Eastern Caribbean which has traditionally been viewed the dynamic nature of the northeastern Caribbean, underscoring the significant effect of periodic intrusions

Gilbes, Fernando

124

Time-series comparisons of MIPAS Level 2 products with climatology  

E-Print Network [OSTI]

Time-series comparisons of MIPAS Level 2 products with climatology V. Payne, A. Dudhia, C. Piccolo) for the calculation of the means. Here we compare these monthly means with reference climatologies for each that MIPAS has been operating. The reference climatologies used in these comparisons are the COSPAR Reference

Oxford, University of

125

The 30-year TAMSAT African Rainfall Climatology1 And Time-series (TARCAT) Dataset  

E-Print Network [OSTI]

Page 1 The 30-year TAMSAT African Rainfall Climatology1 And Time-series (TARCAT) Dataset 2 Authors 2 Key points1 Development of a satellite based 30 year rainfall dataset for Africa2 The dataset has been designed to be temporally consistency3 The dataset skilfully captures interannual

Allan, Richard P.

126

Directed Monitoring Using Cuscore Charts for Seasonal Time Series Harriet Black Nembhard*  

E-Print Network [OSTI]

a special cause in a process, statistical process control (SPC) charts are traditionally used. If the data1 Directed Monitoring Using Cuscore Charts for Seasonal Time Series Harriet Black Nembhard used statistical process control charts to detect special causes are Shewhart and Cusum charts. However

Nembhard, Harriet Black

127

A new measure of phase synchronization for a pair of time series and seizure focus localization  

E-Print Network [OSTI]

Defining and measuring phase synchronization in a pair of nonlinear time series are highly nontrivial. This can be done with the help of Fourier transform, when it exists, for a pair of stored (hence stationary) signals. In a time series instantaneous phase is often defined with the help of Hilbert transform. In this paper phase of a time series has been defined with the help of Fourier transform. This gives rise to a deterministic method to detect phase synchronization in its most general form between a pair of time series. Since this is a stricter method than the statistical methods based on instantaneous phase, this can be used for lateralization and source localization of epileptic seizures with greater accuracy. Based on this method a novel measure of phase synchronization, called syn function, has been defined, which is capable of quantifying neural phase synchronization and asynchronization as important parameters of epileptic seizure dynamics. It has been shown that such a strict measure of phase synchronization has potential application in seizure focus localization from scalp electroencephalogram (EEG) data, without any knowledge of electrical conductivity of the head.

Kaushik Majumdar

2006-12-22T23:59:59.000Z

128

RESEARCH ARTICLE Time series analysis of infrared satellite data for detecting  

E-Print Network [OSTI]

successfully detected ther- mal anomalies in TIR data from the Advanced Very High Resolution Radiometer (AVHRR algorithm that analyzes thermal infrared satellite time series data to detect and quantify the excess energy. These instruments provide data over potentially dangerous, high-temperature phenomena, such as volcanic eruptions

Wright, Robert

129

Recognising Visual Patterns to Communicate Gas Turbine Time-Series Data  

E-Print Network [OSTI]

Recognising Visual Patterns to Communicate Gas Turbine Time-Series Data Jin Yu, Jim Hunter, Ehud analogue channels are sampled once per second and archived by the Tiger system for monitoring gas turbines that it is very important to identify such patterns in any attempt at summarisation. In the gas turbine domain

Reiter, Ehud

130

Indexing of Time Series by Major Minima and Maxima Eugene Fink  

E-Print Network [OSTI]

sets: stock prices, air and sea temperatures, and wind speeds. Keywords: Compression, indexing.ics.uci.edu). Wind speeds: We have used daily wind speeds at twelve sites in Ireland, from 1961 to 1978, ob­ tained. Indexing: The indexing of a time­series database is based on the notion of major inclines, illustrated

Fink, Eugene

131

Indexing of Time Series by Major Minima and Maxima Eugene Fink  

E-Print Network [OSTI]

sets: stock prices, air and sea temperatures, and wind speeds. Keywords: Compression, indexing.ics.uci.edu). Wind speeds: We have used daily wind speeds at twelve sites in Ireland, from 1961 to 1978, ob- tained. Indexing: The indexing of a time-series database is based on the notion of major inclines, illustrated

Fink, Eugene

132

BN-97-4-4 (RP-875) The Radiant Time Series Cooling  

E-Print Network [OSTI]

of the proceduresare described in chapters 2 and 10 of the current ASHRAECool#zg and Heating LoadCalculation ManualBN-97-4-4 (RP-875) The Radiant Time Series Cooling Load Calculation Procedure Jeffrey D. Spitler calculations, derived from the heat balancemethod.It effectively replacesall other simpli- fied (non-heat

133

APPLICATION OF TEMPORAL TEXTURE FEATURES TO AUTOMATED ANALYSIS OF PROTEIN SUBCELLULAR LOCATIONS IN TIME SERIES FLUORESCENCE  

E-Print Network [OSTI]

are in constant movement within the cell, we extended our studies to time series images, which contain both to identify a protein's subcellular location is to label it with fluorescent dye, take microscope images this last step. The automated approach is more objective and sensitive than visual examination, and single

Gordon, Geoffrey J.

134

Analysis of Brain States from Multi-Region LFP Time-Series  

E-Print Network [OSTI]

Analysis of Brain States from Multi-Region LFP Time-Series Kyle Ulrich 1 , David E. Carlson 1 field potential (LFP) is a source of information about the broad patterns of brain activity. It is believed that these regions may jointly constitute a "brain state," relating to cognition and behavior

Carin, Lawrence

135

Bispectral-Based Methods for Clustering Time Series Jane L. Harvill  

E-Print Network [OSTI]

the ratios. As an example, we apply the method to a set of time series of intensities of gamma-ray bursts, some of which exhibit nonlinear behavior; this enables us to identify gamma-ray bursts that may. As an example, we apply the bispectral-based clustering technique to a set of gamma-ray burst (GRB) intensity

Ravishanker, Nalini

136

DAMAGE DETECTION IN A WIND TURBINE BLADE BASED ON TIME SERIES Simon Hoell, Piotr Omenzetter  

E-Print Network [OSTI]

DAMAGE DETECTION IN A WIND TURBINE BLADE BASED ON TIME SERIES METHODS Simon Hoell, Piotr Omenzetter, the consequences are growing sizes of wind turbines (WTs) and erections in remote places, such as off in the past years, thus efficient energy harvesting becomes more important. For the sector of wind energy

Boyer, Edmond

137

A Novel Approach to the Analysis of Nonlinear Time Series with Applications to Financial Data  

E-Print Network [OSTI]

LIST OF FIGURES : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : ix CHAPTER I INTRODUCTION : : : : : : : : : : : : : : : : : : : : : : : : : : 1 II THE QUANTILE SPECTRAL DENSITY AND COMPAR- ISON BASED TESTS FOR NONLINEAR TIME SERIES... : : : 5 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . 5 2. The quantile spectral density and the test statistic . . . . . 7 3. Sampling properties . . . . . . . . . . . . . . . . . . . . . . 18 4. Testing for equality of serial...

Lee, Jun Bum

2012-07-16T23:59:59.000Z

138

Measurements of time average series resonance effect in capacitively coupled radio frequency discharge plasma  

SciTech Connect (OSTI)

Self-excited plasma series resonance is observed in low pressure capacitvely coupled radio frequency discharges as high-frequency oscillations superimposed on the normal radio frequency current. This high-frequency contribution to the radio frequency current is generated by a series resonance between the capacitive sheath and the inductive and resistive bulk plasma. In this report, we present an experimental method to measure the plasma series resonance in a capacitively coupled radio frequency argon plasma by modifying the homogeneous discharge model. The homogeneous discharge model is modified by introducing a correction factor to the plasma resistance. Plasma parameters are also calculated by considering the plasma series resonances effect. Experimental measurements show that the self-excitation of the plasma series resonance, which arises in capacitive discharge due to the nonlinear interaction of plasma bulk and sheath, significantly enhances both the Ohmic and stochastic heating. The experimentally measured total dissipation, which is the sum of the Ohmic and stochastic heating, is found to increase significantly with decreasing pressure.

Bora, B.; Bhuyan, H.; Favre, M.; Wyndham, E.; Chuaqui, H. [Facultad de Fisica, Pontificia Universidad Catolica de Chile, Ave. Vicuna Mackenna 4860, Santiago 22 (Chile); Kakati, M. [Thermal Plasma Processed Materials Laboratory, Centre of Plasma Physics, Institute for Plasma Research, Sonapur 782 402, Assam (India)

2011-10-15T23:59:59.000Z

139

MEPSA: a flexible peak search algorithm designed for uniformly spaced time series  

E-Print Network [OSTI]

We present a novel algorithm aimed at identifying peaks within a uniformly sampled time series affected by uncorrelated Gaussian noise. The algorithm, called "MEPSA" (multiple excess peak search algorithm), essentially scans the time series at different timescales by comparing a given peak candidate with a variable number of adjacent bins. While this has originally been conceived for the analysis of gamma-ray burst light (GRB) curves, its usage can be readily extended to other astrophysical transient phenomena, whose activity is recorded through different surveys. We tested and validated it through simulated featureless profiles as well as simulated GRB time profiles. We showcase the algorithm's potential by comparing with the popular algorithm by Li and Fenimore, that is frequently adopted in the literature. Thanks to its high flexibility, the mask of excess patterns used by MEPSA can be tailored and optimised to the kind of data to be analysed without modifying the code. The C code is made publicly availabl...

Guidorzi, C

2015-01-01T23:59:59.000Z

140

Using Fourier Series to Model Hourly Energy Use in Commercial Buildings  

E-Print Network [OSTI]

Fourier series analysis is eminently suitable for modeling strongly periodic data. Weather independent energy use such as lighting and equipment load in commercial buildings is strongly periodic and is thus appropriate for Fourier series treatment...

Dhar, A.; Reddy, T. A.; Claridge, D. E.

1993-01-01T23:59:59.000Z

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


141

Noncommutative space-time models  

E-Print Network [OSTI]

The FRT quantum Euclidean spaces $O_q^N$ are formulated in terms of Cartesian generators. The quantum analogs of N-dimensional Cayley-Klein spaces are obtained by contractions and analytical continuations. Noncommutative constant curvature spaces are introduced as a spheres in the quantum Cayley-Klein spaces. For N=5 part of them are interpreted as the noncommutative analogs of (1+3) space-time models. As a result the quantum (anti) de Sitter, Newton, Galilei kinematics with the fundamental length and the fundamental time are suggested.

N. A. Gromov; V. V. Kuratov

2005-07-01T23:59:59.000Z

142

Exploration of period-doubling cascade route to chaos with complex network based time series construction  

E-Print Network [OSTI]

In this work, the topologies of networks constructed from time series from an underlying system undergo a period doubling cascade have been explored by means of the prevalence of different motifs using an efficient computational motif detection algorithm. By doing this we adopt a refinement based on the $k$ nearest neighbor recurrence-based network has been proposed. We demonstrate that the refinement of network construction together with the study of prevalence of different motifs allows a full explosion of the evolving period doubling cascade route to chaos in both discrete and continuous dynamical systems. Further, this links the phase space time series topologies to the corresponding network topologies, and thus helps to understand the empirical "superfamily" phenomenon, as shown by Xu.

Ruoxi Xiang; Michael Small

2014-06-18T23:59:59.000Z

143

Time series analysis, 2013, PC 8 | ARCH and GARCH processes 9 8 ARCH and GARCH processes  

E-Print Network [OSTI]

Time series analysis, 2013, PC 8 | ARCH and GARCH processes 9 8 ARCH and GARCH processes A GARCH(q) process. Exercise 8.2 (Computation of the kurtosis of a conditionally Gaussian GARCH(1, 1) pro- cess that = 3 + 3 Var(E[X2 t | Gt 1]) (E[X2 t ])2 . 3. For a GARCH(1,1) process, with p = q = 1 and a, b = b1, c

Gaïffas, Stéphane

144

A test for second order stationarity of a time series based on the Discrete Fourier Transform -Technical report  

E-Print Network [OSTI]

A test for second order stationarity of a time series based on the Discrete Fourier Transform stationary. Exploiting this important property, we construct a Portmanteau type test statistic for testing stationarity of the time series. It is shown that under the null of stationarity, the test statistic has

Subba Rao, Suhasini

145

Interactive Poster: 3D Axes-Based Visualizations for Time Series Data Christian Tominski James Abello Heidrun Schumann  

E-Print Network [OSTI]

that can be used to explore and analyze multivariate time series data. We propose different types of drawings. 1 INTRODUCTION The analysis of time series data is a fundamental task addressed by information of multivariate data is not a new topic to information visualization researchers. A variety of approaches have

Tominski, Christian

146

Hurst exponent of very long birth time series in XX century Romania. Social and religious aspects  

E-Print Network [OSTI]

The Hurst exponent of very long birth time series in Romania has been extracted from official daily records, i.e. over 97 years between 1905 and 2001 included. The series result from distinguishing between families located in urban (U) or rural (R) areas, and belonging (Ox) or not (NOx) to the orthodox religion. Four time series combining both criteria, (U,R) and (Ox, NOx), are also examined. A statistical information is given on these sub-populations measuring their XX-th century state as a snapshot. However, the main goal is to investigate whether the "daily" production of babies is purely noisy or is fluctuating according to some non trivial fractional Brownian motion, - in the four types of populations, characterized by either their habitat or their religious attitude, yet living within the same political regime. One of the goals was also to find whether combined criteria implied a different behavior. Moreover, we wish to observe whether some seasonal periodicity exists. The detrended fluctuation analysis...

Rotundo, G; Herteliu, C; Ileanu, B

2015-01-01T23:59:59.000Z

147

MODEL-DRIVEN ENGINEERING FOR IMPLEMENTING THE ISO 19100 SERIES OF INTERNATIONAL STANDARDS  

E-Print Network [OSTI]

MODEL-DRIVEN ENGINEERING FOR IMPLEMENTING THE ISO 19100 SERIES OF INTERNATIONAL STANDARDS CYRIL of the ISO 19100 series of standards with use of Model-Driven Engineering (MDE) techniques. We expose how MDE to use ISO 19109, 19110 and 19117 models in order to generate a rich client application. Our work takes

Paris-Sud XI, Université de

148

Transportation Energy Futures Series: Vehicle Technology Deployment Pathways: An Examination of Timing and Investment Constraints  

SciTech Connect (OSTI)

Scenarios of new vehicle technology deployment serve various purposes; some will seek to establish plausibility. This report proposes two reality checks for scenarios: (1) implications of manufacturing constraints on timing of vehicle deployment and (2) investment decisions required to bring new vehicle technologies to market. An estimated timeline of 12 to more than 22 years from initial market introduction to saturation is supported by historical examples and based on the product development process. Researchers also consider the series of investment decisions to develop and build the vehicles and their associated fueling infrastructure. A proposed decision tree analysis structure could be used to systematically examine investors' decisions and the potential outcomes, including consideration of cash flow and return on investment. This method requires data or assumptions about capital cost, variable cost, revenue, timing, and probability of success/failure, and would result in a detailed consideration of the value proposition of large investments and long lead times. This is one of a series of reports produced as a result of the Transportation Energy Futures (TEF) project, a Department of Energy-sponsored multi-agency effort to pinpoint underexplored strategies for abating GHGs and reducing petroleum dependence related to transportation.

Plotkin, S.; Stephens, T.; McManus, W.

2013-03-01T23:59:59.000Z

149

Learning Dynamic Systems From Time-Series Data - An Application to Gene Regulatory Networks  

E-Print Network [OSTI]

the second half of the time-series data provided; that is, from the point when the pertur- bation is lifted, as we do not know the exact nature of the perturbation. The DREAM4 Challenge evaluated performance using the p-values for the area under the ROC curve... ., and Druzdzel, M. (2010). Learn- ing why things change: The difference-based causal- ity learner. In Proceedings of the Twenty-Sixth An- nual Conference on Uncertainty in Artificial Intelli- gence (UAI). Yip, K., Alexander, R., Yan, K., and Gerstein, M. (2010...

Timoteo, Ivo J. P. M.; Holden, Sean B.

2015-01-01T23:59:59.000Z

150

Power spectra of fossil biodiversity time series: a connection with Galactic dynamics?  

E-Print Network [OSTI]

Systematic error is a major issue in the quantitative analysis of fossil biodiversity data in paleontology. I present results of time series analysis of a new and expanded data set (the Paleobiology Database) controlled and corrected for systematic error, and find that periodicities at approximately 62 and 150 Myr reported from previous data emerge at higher significance than before. This provides increased confidence that the periodicities are not collection, sampling, or binning artifacts. Both of these timescales are interestingly close to dynamical timescales of Solar motion in the Milky Way galaxy.

Melott, Adrian L

2008-01-01T23:59:59.000Z

151

Sandia National Laboratories: virtual time series of solar power-plant  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administrationcontroller systems controller systems Scaled Wind Farmoutput virtual time series

152

Modeling North Pacific Climate Time Series Don Percival  

E-Print Network [OSTI]

-- autocovariance sequence (ACVS) and -- spectral density function (SDF) . essential di#erence between processes and SDF given by s X,# # cov{X t , X t+# } = # 2 # # |# | 1 - # 2 & SX (f ) = # 2 # 1 + # 2 - 2# cos(2#f noise; LM if # > 0) . ACVS and SDF given by s Y,# = # 2 # sin(##)#(1 - 2#)#(# + #) ##(# + 1 - #) & S Y

Percival, Don

153

Modeling North Pacific Climate Time Series Don Percival  

E-Print Network [OSTI]

­ autocovariance sequence (ACVS) and ­ spectral density function (SDF) · essential difference between processes with mean zero and variance 2 3. || SDF given by sX, cov if > 0) · ACVS and SDF given by sY, = 2 sin()(1 - 2)( + ) ( + 1 - ) & SY (f) = 2 |2 sin(f)|2 · for 1

Percival, Don

154

A Software Tool for Processing the Displacement Time Series Extracted from Raw Radar Data  

SciTech Connect (OSTI)

The application of high-resolution radar waveform and interferometric principles recently led to the development of a microwave interferometer, suitable to simultaneously measuring the (static or dynamic) deflection of several points on a large structure. From the technical standpoint, the sensor is a Stepped Frequency Continuous Wave (SF-CW), coherent radar, operating in the K{sub u} frequency band.In the paper, the main procedures adopted to extract the deflection time series from raw radar data and to assess the quality of data are addressed, and the MATLAB toolbox developed is described. Subsequently, other functions implemented in the software tool (e.g. evaluation of the spectral matrix of the deflection time-histories, identification of natural frequencies and operational mode shapes evaluation) are described and the application to data recorded on full-scale bridges is exemplified.

Coppi, Francesco; Paolo Ricci, Pier [IDS Ingegneria Dei Sistemi S.p.A., Pisa (Italy); Gentile, Carmelo [Politecnico di Milano, Dept. of Structural Engineering, Milan (Italy)

2010-05-28T23:59:59.000Z

155

Modeling of ECM Controlled Series Fan-powered VAV Terminal Units  

E-Print Network [OSTI]

Semi-empirical models for series fan-powered variable air volume terminal units (FPTUs) were developed based on models of the primary, plenum, fan airflow and the fan power consumption. The experimental setups and test procedures were developed...

Yin, Peng

2011-10-21T23:59:59.000Z

156

Mesoscale variability in time series data: Satellite-based estimates for the U.S. JGOFS Bermuda Atlantic  

E-Print Network [OSTI]

Atlantic Time-Series Study (BATS) site David M. Glover,1 Scott C. Doney,2 Arthur J. Mariano,3 Robert H errors, and unresolved three-dimensional effects [Glover and Doney, 1996; Glover et al., 1998]. The appro

157

Studying complex tourism systems: a novel approach based on networks derived from a time series  

E-Print Network [OSTI]

A tourism destination is a complex dynamic system. As such it requires specific methods and tools to be analyzed and understood in order to better tailor governance and policy measures for steering the destination along an evolutionary growth path. Many proposals have been put forward for the investigation of complex systems and some have been successfully applied to tourism destinations. This paper uses a recent suggestion, that of transforming a time series into a network and analyzes it with the objective of uncovering the structural and dynamic features of a tourism destination. The algorithm, called visibility graph, is simple and its implementation straightforward, yet it is able to provide a number of interesting insights. An example is worked out using data from two destinations: Italy as a country and the island of Elba, one of its most known areas.

Baggio, Rodolfo

2013-01-01T23:59:59.000Z

158

Multiple Alignment of Continuous Time Series Jennifer Listgarten y , Radford M. Neal y , Sam T. Roweis y and Andrew Emili z  

E-Print Network [OSTI]

Multiple Alignment of Continuous Time Series Jennifer Listgarten y , Radford M. Neal y , Sam T of continuous­valued time series from a stochastic process often contain systematic variations in rate time series generated by a noisy, stochastic process, large sys­ tematic sources of variability

Roweis, Sam

159

A Latent Time-Budget Model  

E-Print Network [OSTI]

DE L E E U W (1989), Latent budget analysis, in: A. DECARLI,DER H E U D E N (1988), The analysis of time- budgets with alatent-time-budget model, in E. Diday et al. (eds. ), Data

Jan de Leeuw; Peter G.M. van der Heijden; Peter Verboon

2011-01-01T23:59:59.000Z

160

Reverberation mapping of active galactic nuclei : The SOLA method for time-series inversion  

E-Print Network [OSTI]

In this paper a new method is presented to find the transfer function of the broad-line region in active galactic nuclei. The subtractive optimally localized averages (SOLA) method is a modified version of the Backus-Gilbert method and is presented as an alternative to the more often used maximum-entropy method. The SOLA method has been developed for use in helioseismology. It has been applied to the solar oscillation frequency splitting data currently available to deduce the internal rotation rate of the sun. The original SOLA method is reformulated in the present paper to cope with the slightly different problem of inverting time series. We use simulations to test the viability of the method and apply the SOLA method to the real data of the Seyfert-1 galaxy NGC 5548. We investigate the effects of measurement errors and how the resolution of the TF critically depends upon both the sampling rate and the photometric accuracy of the data. A uuencoded compressed postscript file of the paper which includes the figures is available by anonymous ftp at ftp://solaris.astro.uu.se/pub/articles/atmos/frank/PijWan.uue

Frank P. Pijpers; Ignaz Wanders

1994-06-27T23:59:59.000Z

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


161

A Scientific Data Processing Framework for Time Series NetCDF Data  

SciTech Connect (OSTI)

ARM Data Integrator (ADI) is a framework to streamline the development of scientific algorithms that analyze time-series NetCDF data, and to improve the content and consistency of the output data products produced by these algorithms. ADI achieves these goals by automating the process of retrieving and preparing data for analysis, supporting the definition of output data products through a graphical interface, and providing a modular, flexible software development architecture. The input data, preprocessing, and output data specifications are defined through a graphical interface and stored in a database. ADI also includes a workflow for data integration, a library of software modules to support the workflow, and a source code generator that produces C, IDL and Python templates. Data preparation support includes automated retrieval of data from input files, merging the retrieved data into appropriately sized chunks, and transformation of the data onto a common coordinate system grid. Through the graphical interface, users can view the details of both their data products and those in the ARM catalog. The variable and attribute definitions of the existing data products can be used to build new output data products. In addition, the rules that make up the ARM archive’s data standards are laid on top of the view of the new data product providing the user with a visual cue indicating where their output violates an archive standard. The necessary configurations are stored in a database that is accessed by the ADI libraries. This paper discusses the ADI framework, its supporting components, and how ADI can significantly decrease the time and cost of implementing scientific algorithms while improving the ability of scientists to disseminate their results.

Gaustad, Krista L.; Shippert, Timothy R.; Ermold, Brian D.; Beus, Sherman J.; Daily, Jeffrey A.; Borsholm, Atle; Fox, Kevin M.

2014-10-01T23:59:59.000Z

162

Time-series analysis of participation in nonresident hunting: the effects of license cost and quantitative fluctuations in supply.  

E-Print Network [OSTI]

TIME -SERIES ANAI, YSIS OI' PARTICIPATION IN NQiIRESI DEN I. ' HUNTING: Tl-;E EFFECTS OI LICENSE COST ANI3 QUANTITATIVE I LUC fUWTIONS IN SVPPI. Y A lil*sis by ANTHONY PETER MAZZACCARO Subrnittc. d to the Gracluate College of Teresa ARM Unic... AND QUANTITATIVE Fl UCTUATIONS IN SUPPLY A Thesis by ANTHONY PETER IvlAZZACCARO Approved as to style and content: (Chairman of Conrrnittee) ead of Department) ( ivl e rnb e g ~. , 8! (Member) +~eg ~+ ABSTRACT Time-Series Analysis of Participation...

Mazzaccaro, Anthony Peter

1974-01-01T23:59:59.000Z

163

Fortuna: Model Checking Priced Probabilistic Timed Automata  

E-Print Network [OSTI]

Fortuna: Model Checking Priced Probabilistic Timed Automata Jasper Berendsen, David N. Jansen.O. Box 9010, 6500 GL Nijmegen, the Netherlands Abstract. We introduce Fortuna, the first tool for model checking priced probabilistic timed automata (PPTAs). Fortuna can handle the combination of real

Vaandrager, Frits

164

Fortuna: Model Checking Priced Probabilistic Timed Automata  

E-Print Network [OSTI]

Fortuna: Model Checking Priced Probabilistic Timed Automata Jasper Berendsen, David N. Jansen, the Netherlands Email: jasperb,dnjansen,fvaan @cs.ru.nl Abstract--We introduce FORTUNA, the first tool for model of probabilistic timed automata (PTAs) with cost-rates and discrete cost increments on states. FORTUNA is able

Vaandrager, Frits

165

Bayesian inference for pulsar timing models  

E-Print Network [OSTI]

The extremely regular, periodic radio emission from millisecond pulsars make them useful tools for studying neutron star astrophysics, general relativity, and low-frequency gravitational waves. These studies require that the observed pulse time of arrivals are fit to complicated timing models that describe numerous effects such as the astrometry of the source, the evolution of the pulsar's spin, the presence of a binary companion, and the propagation of the pulses through the interstellar medium. In this paper, we discuss the benefits of using Bayesian inference to obtain these timing solutions. These include the validation of linearized least-squares model fits when they are correct, and the proper characterization of parameter uncertainties when they are not; the incorporation of prior parameter information and of models of correlated noise; and the Bayesian comparison of alternative timing models. We describe our computational setup, which combines the timing models of tempo2 with the nested-sampling integ...

Vigeland, Sarah J

2013-01-01T23:59:59.000Z

166

Time reversal symmetry and collapse models  

E-Print Network [OSTI]

Collapse models are modifications of quantum theory where the wave function is treated as physically real and the collapse of the wave function is a physical process. This appears to introduce a time reversal asymmetry into the dynamics of the wave function since the collapses affect only the future state. This paper challenges this conclusion, showing that in three different examples of time asymmetries associated with collapse models, if the physically real part of the model can be reduced to the locations in space and time about which collapses occur, then such a model works both forward and backward in time, in each case satisfying the Born rule. Despite the apparent asymmetry of the collapse process, these models in fact have time reversal symmetry. Any physically observed time asymmetries that arise in such models are due to the asymmetric imposition of initial or final time boundary conditions, rather than from an inherent asymmetry in the dynamical law. This is the standard explanation of time asymmetric behaviour resulting from time symmetric laws.

Daniel Bedingham; Owen Maroney

2015-02-24T23:59:59.000Z

167

Time symmetry in wave function collapse models  

E-Print Network [OSTI]

A framework for wave function collapse models that is symmetric under time reversal is presented. Within this framework there are equivalent pictures of collapsing wave functions evolving in both time directions. The backwards-in-time Born rule can be broken by an initial condition on the Universe resulting in asymmetric behaviour. Similarly the forwards-in-time Born rule can in principle be broken by a final condition on the Universe.

Daniel Bedingham

2015-02-25T23:59:59.000Z

168

Reconstructing long time series of burned areas in arid grasslands of southern Russia by satellite remote sensing  

E-Print Network [OSTI]

Reconstructing long time series of burned areas in arid grasslands of southern Russia by satellite of Sciences, 33 Leninskiy prospect, Moscow, 119071 Russia a b s t r a c ta r t i c l e i n f o Article history: AVHRR MODIS RESURS Landsat Burned area mapping Southern Russia Arid grasslands Grazing Fire

Radeloff, Volker C.

169

Comparing modern and Pleistocene ENSO-like influences in NW Argentina using nonlinear time series analysis methods  

E-Print Network [OSTI]

Comparing modern and Pleistocene ENSO-like influences in NW Argentina using nonlinear time series of 106 m3 occurred in the arid to semiarid intra-Andean basins of northwest- ern Argentina (Strecker Argentina are not well known for the period at around 30,000 14 C years ago. Marine and terrestrial records

Vuille, Mathias

170

Micro-phytoplankton variability at the equatorial Pacific (140W?) during the JGOFS EQPAC Time Series Studies 1992  

E-Print Network [OSTI]

Micro-phytoplankton (>20 gm cell size) was sampled in the upper 200 m of the water column at the Pacific equator, 140'W, during two JGOFS EqPac Time Series Studies, in order to determine the changes in the micro-phytoplanlcton assemblage between...

Iriarte, Jose Luis

1994-01-01T23:59:59.000Z

171

Glacier mass balance determination by Remote Sensing in the French Alps: Progress and limitation for time series monitoring  

E-Print Network [OSTI]

measurements. A recent time series of images from optical and SAR data are selected on 3 outlet glaciers well-scale areas. The limitations are cloudiness for optical data and high slope distortion on SAR images. I resolution, repeat coverage, radiometric calibration and stereo capabilities (automatic generation of DEM

Rabatel, Antoine

172

High-frequency precipitation and stream water quality time series from Plynlimon, Wales: an openly accessible data  

E-Print Network [OSTI]

High-frequency precipitation and stream water quality time series from Plynlimon, Wales: an openly Colin Vincent,6 Kathryn Lehto,6 Simon Grant,2 Jeremy Williams,7 Margaret Neal,1 Heather Wickham,1 Sarah-element high- frequency water quality data set that is openly accessible to the research community. The data

Kirchner, James W.

173

Modeling reaction time within a traffic simulation model  

E-Print Network [OSTI]

Human reaction time has a substantial effect on modeling of human behavior at a microscopic level. Drivers and pedestrian do not react to an event instantaneously; rather, they take time to perceive the event, process the ...

Basak, Kakali

174

WBI Ceilometer/MLH andWBI Ceilometer/MLH and CO2 Time Series  

E-Print Network [OSTI]

99 m 420 460 mole/mole 99 m 379 m 340 380 CO2um Time where tower levels 1&2 become well mixed Time/mole 99 m 379 m 340 380 CO2um Time where tower levels 1&2 become well mixed Time where tower levels 1 379 m 340 380 CO2um Time where tower levels 1&2 become well mixed Time where tower levels 1-3 become

Stanier, Charlie

175

IMA Preprints Series (2002) Micro-and macro-scopic models of rock fracture  

E-Print Network [OSTI]

IMA Preprints Series (2002) Micro- and macro-scopic models of rock fracture Donald L. Turcotte to some earthquakes. Key words: rock mechanics, damage, fracture, critical point, power-law scaling, self involve a sin- gle fracture propagating through an homogeneous solid. However, this is an idealized case

176

IMA Preprints Series (2002) Micro and macroscopic models of rock fracture  

E-Print Network [OSTI]

IMA Preprints Series (2002) Micro­ and macro­scopic models of rock fracture Donald L. Turcotte to some earthquakes. Key words: rock mechanics, damage, fracture, critical point, power­law scaling, self involve a sin­ gle fracture propagating through an homogeneous solid. However, this is an idealized case

177

F2010-B-107 MODELING OF THE THS-II SERIES/PARALLEL POWER TRAIN AND  

E-Print Network [OSTI]

F2010-B-107 MODELING OF THE THS-II SERIES/PARALLEL POWER TRAIN AND ITS ENERGY MANAGEMENT SYSTEM ­ Hybrid power train, power-split eCVT, rule-based control strategy, Toyota Hybrid System, driver the challenge of minimizing the consumption of the road transport. Although hybrid power train technologies did

Paris-Sud XI, Université de

178

Development of models for series and parallel fan variable air volume terminal units  

E-Print Network [OSTI]

for the series and parallel units, with coefficients varying by size and manufacturer. Statistical modeling utilized SAS software (2002). Fan power and airflow data were collected at downstream static pressures over a range from 0.1 to 0.5 in. w.g. (25 to 125 Pa...

Furr, James C., Jr

2007-09-17T23:59:59.000Z

179

Model study of shoreline changes due to a series of offshore breakwaters  

E-Print Network [OSTI]

MODEL STUDY OF SHORELINE CHANGES DUE TO A SERIES OF OFFSHORE BREAKHATERS A Thesis by DONALD ALAN CORDS Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE... May 1986 Hajor Subject: Ocean Engineering NODEL STUDY OF SHORELINE CHANGES DUE TD A SERIES OF OFFSHORE BREAKHATERS A Thesis by DONALD ALAN CORDS Approved as to style and content by: ohn . er sc (Chairman) o ert . a a (Nember ) o er . ei...

Cords, Donald Alan

2012-06-07T23:59:59.000Z

180

Metamaterial model of a time crystal  

E-Print Network [OSTI]

Propagation of monochromatic extraordinary light in a hyperbolic metamaterial is identical to propagation of massive particles in a three dimensional effective Minkowski spacetime, in which the role of a timelike variable is played by one of the spatial coordinates. We demonstrate that this analogy may be used to build a metamaterial model of a time crystal, which has been recently suggested by Wilczek and Shapere. It is interesting to note that the effective single-particle energy spectrum in such a model does not contain a static ground state, thus providing a loophole in the proof of time crystal non-existence by P. Bruno.

Smolyaninov, Igor I

2015-01-01T23:59:59.000Z

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


181

SATELLITE BASED ASSESSMENT OF THE NSRDB SITE IRRADIANCES AND TIME SERIES FROM  

E-Print Network [OSTI]

sets from two models, the Meteorological-Statistical (METSTAT) model [2] and the State University of New York (SUNY) model [3]. The 1991-2005 NSRDB has data from 1,454 ground sites that are divided continuous, and over 99% of its data are modeled and less than 1% are from instrumental measurements

Perez, Richard R.

182

An Approach to Generating Summaries of Time Series Data in the Gas Turbine Domain Jin Yu and Jim Hunter and Ehud Reiter and Somayajulu Sripada  

E-Print Network [OSTI]

An Approach to Generating Summaries of Time Series Data in the Gas Turbine Domain Jin Yu and Jim an approach to generating summaries of time series data in the gas turbine domain using AI techniques. Through), both domain knowledge from experts about how to solve problems in the gas turbine and information about

Sripada, Yaji

183

CITED REFERENCES Acevedo, W; Masuoka, P. 1997. Time-Series Animation Techniques for Visualizing  

E-Print Network [OSTI]

. Transactions of the ASAE, 23(4): 938-944. Bennet, JP. 1974. Concepts of Mathematical Modeling of Sediment Yield

Julien, Pierre Y.

184

Modelling Reliability of Train Arrival Times  

E-Print Network [OSTI]

This paper deals with the scheduling of trains so as to minimise train trip times, whilst maximising reliability of arrival times. The amount of risk of delay associated with a schedule is used as the reliability component of a constrained schedule optimisation model. The paper outlines the model developed to quantify the risk of delays to individual trains, as well as to specific track segments and to the schedule as a whole. The risk model, which deals with single track operations, can be used to estimate the likely impact on reliability of arrival times of changes in train frequencies and operating practices; track and station infrastructure investment strategies; and train technology upgrading. An application of the model to the optimisation of schedules on a track corridor is described. The results obtained using the model are compared with the schedules used by train operations planning staff, in terms of overall delay and timetable reliability. The results highlight the significance of including a measure of timetable reliability, such as risk of delays, in the objective function for scheduling optimisation.

L. Ferreira; A. Higgins

185

A Time Series Analysis of Food Price and Its Input Prices  

E-Print Network [OSTI]

....................................... 27 4.5 Residual Correlation Matrix of the VECM ................................................ 28 4.6 Decomposition of Forecast Error Variance for Each of Eight Series ........ 40 1 CHAPTER I INTRODUCTION Global food prices have....94 0.50 2.96 4.90 .13 Gasoline 0.79 0.34 0.12 1.41 .43 Corn 1.06 0.43 0.40 1.99 .41 Food CPI 5.28 0.10 5.12 5.45 .02 Ethanol 0.59 0.29 -0.06 1.29 .49 Food PPI 5.03 0.13 4.84 5.28 .03 Fuel PPI 4.98 0.29 4.41 5.59 .06 Dollar Index 4.70 0.09 4.55 4...

Routh, Kari 1988-

2012-11-27T23:59:59.000Z

186

Hubble expansion & Structure Formation in Time Varying Vacuum Models  

E-Print Network [OSTI]

We investigate the properties of the FLRW flat cosmological models in which the vacuum energy density evolves with time, $\\Lambda(t)$. Using different versions of the $\\Lambda(t)$ model, namely quantum field vacuum, power series vacuum and power law vacuum, we find that the main cosmological functions such as the scale factor of the universe, the Hubble expansion rate $H$ and the energy densities are defined analytically. Performing a joint likelihood analysis of the recent supernovae type Ia data, the Cosmic Microwave Background (CMB) shift parameter and the Baryonic Acoustic Oscillations (BAOs) traced by the Sloan Digital Sky Survey (SDSS) galaxies, we put tight constraints on the main cosmological parameters of the $\\Lambda(t)$ scenarios. Furthermore, we study the linear matter fluctuation field and the growth rate of clustering of the above vacuum models. Finally, we derived the theoretically predicted dark-matter halo mass function and the corresponding distribution of cluster-size halos for all the models studied. Their expected redshift distribution indicates that it will be difficult to distinguish the closely resembling models (constant vacuum, quantum field and power-law vacuum), using realistic future X-ray surveys of cluster abundances. However, cluster surveys based on the Sunayev-Zeldovich detection method give some hope to distinguish the closely resembling models at high redshifts.

S. Basilakos; M. Plionis; J. Sola

2009-09-22T23:59:59.000Z

187

A quantum defect model for the s, p, d, and f Rydberg series of CaF  

E-Print Network [OSTI]

We present an improved quantum defect theory model for the “s,” “p,” “d,” and “f” Rydberg series of CaF. The model, which is the result of an exhaustive fit of high-resolution spectroscopic data, parameterizes the electronic ...

Kay, Jeffrey J.

188

Fifteen-year global time series of satellite-derivedfine particulate Boys, B.L.1,*  

E-Print Network [OSTI]

.5 concentration at a resolution of 1° x 1°. The GEOS-Chem chemical transport model (CTM) is used to relate each optical depth (AOD) satellite retrievals, of global chemical transport models (CTMs) and of ground and respiratory morbidity. The WHO air quality guideline (AQG) for PM2.5 of 10 g m-3 is surpassed in most

Martin, Randall

189

Fluorescence spectrum analysis using Fourier series modeling for Fluorescein solution in Ethanol  

E-Print Network [OSTI]

We have measured the fluorescence spectrum for fluorescein solution in ethanol with concentration 1 {\\times} 10-3 mol/liter at different temperatures from room temperature to freezing point of solvent, (T = 153, 183, 223, 253, and 303 K) using liquid nitrogen. Table curve 2D version 5.01 program has been used to determine the fitting curve and fitting equation for each fluorescence spectrum. Fourier series (3 {\\times} 2) was the most suitable fitting equation for all spectra. Theoretical fluorescence spectrum of fluorescein in ethanol at T = 183K was calculated and compared with experimental fluorescence spectrum at the same temperature. There is a good similarity between them.

Hadi, Mahasin F

2011-01-01T23:59:59.000Z

190

Reedbed monitoring using classification trees and SPOT-5 seasonal time series  

E-Print Network [OSTI]

, Phragmites australis, Remote sensing, SPOT-5. Abstract The Camargue, the Rhône river delta in south of France to model the presence of common reed (Phragmite australis) stands in Camargue. The development

Paris-Sud XI, Université de

191

Private and Dynamic Time-Series Data Aggregation with Trust Relaxation  

E-Print Network [OSTI]

of users along a specific time period. These statistics can then help the energy provider perform various operations such as load balancing and forecasting for potential acquirement. Despite its merits, statistical analyzer to compute global statistics over the set of individual inputs that are protected by some

192

Sediment transport time measured with U-Series isotopes: Resultsfrom ODP North Atlantic Drill Site 984  

SciTech Connect (OSTI)

High precision uranium isotope measurements of marineclastic sediments are used to measure the transport and storage time ofsediment from source to site of deposition. The approach is demonstratedon fine-grained, late Pleistocene deep-sea sediments from Ocean DrillingProgram Site 984A on the Bjorn Drift in the North Atlantic. The sedimentsare siliciclastic with up to 30 percent carbonate, and dated by sigma 18Oof benthic foraminifera. Nd and Sr isotopes indicate that provenance hasoscillated between a proximal source during the last three interglacialperiods volcanic rocks from Iceland and a distal continental sourceduring glacial periods. An unexpected finding is that the 234U/238Uratios of the silicate portion of the sediment, isolated by leaching withhydrochloric acid, are significantly less than the secular equilibriumvalue and show large and systematic variations that are correlated withglacial cycles and sediment provenance. The 234U depletions are inferredto be due to alpha-recoil loss of234Th, and are used to calculate"comminution ages" of the sediment -- the time elapsed between thegeneration of the small (<_ 50 mu-m) sediment grains in the sourceareas by comminution of bedrock, and the time of deposition on theseafloor. Transport times, the difference between comminution ages anddepositional ages, vary from less than 10 ky to about 300 to 400 ky forthe Site 984A sediments. Long transport times may reflect prior storagein soils, on continental shelves, or elsewhere on the seafloor. Transporttime may also be a measure of bottom current strength. During the mostrecent interglacial periods the detritus from distal continental sourcesis diluted with sediment from Iceland that is rapidly transported to thesite of deposition. The comminution age approach could be used to dateQuaternary non-marine sediments, soils, and atmospheric dust, and may beenhanced by concomitant measurement of 226Ra/230Th, 230Th/234U, andcosmogenic nuclides.

DePaolo, Donald J.; Maher, Kate; Christensen, John N.; McManus,Jerry

2006-06-05T23:59:59.000Z

193

Time series analysis of AERI radiances for GCM testing and improvement  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear SecurityTensile Strain Switched Ferromagnetism in Layered NbS2 andThe1A:decisional. 1 B O N N E V I L L E1,4,6,7,Time

194

The data this time will be the Motorcycle Acceleration Data: A data frame giving a series of measurements of head acceleration  

E-Print Network [OSTI]

Cosines The data this time will be the Motorcycle Acceleration Data: A data frame giving a series of measurements of head acceleration in a simulated motorcycle accident, used to test crash helmets. Usage: data

Zeng, Donglin

195

Artificial Neural Networks and Support Vector Machines for Water Demand Time Series Forecasting  

E-Print Network [OSTI]

Water plays a pivotal role in many physical processes, and most importantly in sustaining human life, animal life and plant life. Water supply entities therefore have the responsibility to supply clean and safe water at the rate required by the consumer. It is therefore necessary to implement mechanisms and systems that can be employed to predict both short-term and long-term water demands. The increasingly growing field of computational intelligence techniques has been proposed as an efficient tool in the modelling of dynamic phenomena. The primary objective of this paper is to compare the efficiency of two computational intelligence techniques in water demand forecasting. The techniques under comparison are the Artificial Neural Networks (ANNs) and the Support Vector Machines (SVMs). In this study it was observed that the ANNs perform better than the SVMs. This performance is measured against the generalisation ability of the two.

Msiza, Ishmael S; Nelwamondo, Fulufhelo Vincent

2007-01-01T23:59:59.000Z

196

Quantification of depth of anesthesia by nonlinear time series analysis of brain electrical activity  

E-Print Network [OSTI]

We investigate several quantifiers of the electroencephalogram (EEG) signal with respect to their ability to indicate depth of anesthesia. For 17 patients anesthetized with Sevoflurane, three established measures (two spectral and one based on the bispectrum), as well as a phase space based nonlinear correlation index were computed from consecutive EEG epochs. In absence of an independent way to determine anesthesia depth, the standard was derived from measured blood plasma concentrations of the anesthetic via a pharmacokinetic/pharmacodynamic model for the estimated effective brain concentration of Sevoflurane. In most patients, the highest correlation is observed for the nonlinear correlation index D*. In contrast to spectral measures, D* is found to decrease monotonically with increasing (estimated) depth of anesthesia, even when a "burst-suppression" pattern occurs in the EEG. The findings show the potential for applications of concepts derived from the theory of nonlinear dynamics, even if little can be assumed about the process under investigation.

G. Widman; T. Schreiber; B. Rehberg; A. Hoeft; C. E. Elger

2000-07-20T23:59:59.000Z

197

STAT565: APPLIED TIME SERIES ANALYSIS 16:960:565 SPRING 2013, MONDAY 6:40-9:30 PM, ARC 107 BUS  

E-Print Network [OSTI]

STAT565: APPLIED TIME SERIES ANALYSIS 16:960:565 SPRING 2013, MONDAY 6:40-9:30 PM, ARC 107 BUS 1:30-6:00 pm or by appointment · Email: hxiao@stat.rutgers.edu · Prerequisite. First graduate level courses of Financial Time Series, by Ruey S. Tsay. Wiley, 2010, 3rd. Full text available from MyiLibrary http://lib.myilibrary.com/Open.aspx?id

Shepp, Larry

198

Time series of high resolution photospheric spectra in a quiet region of the Sun. II. Analysis of the variation of physical quantities of granular structures  

E-Print Network [OSTI]

From the inversion of a time series of high resolution slit spectrograms obtained from the quiet sun, the spatial and temporal distribution of the thermodynamical quantities and the vertical flow velocity is derived as a function of logarithmic optical depth and geometrical height. Spatial coherence and phase shift analyzes between temperature and vertical velocity depict the height variation of these physical quantities for structures of different size. An average granular cell model is presented, showing the granule-intergranular lane stratification of temperature, vertical velocity, gas pressure and density as a function of logarithmic optical depth and geometrical height. Studies of a specific small and a specific large granular cell complement these results. A strong decay of the temperature fluctuations with increasing height together with a less efficient penetration of smaller cells is revealed. The T -T coherence at all granular scales is broken already at log tau =-1 or z~170 km. At the layers beyon...

Puschmann, K G; Vazquez, M; Bonet, J A; Hanslmeier, A; 10.1051/0004-6361:20047193

2012-01-01T23:59:59.000Z

199

Predicting Time-Delays under Real-Time Scheduling for Linear Model Predictive Control  

E-Print Network [OSTI]

Predicting Time-Delays under Real-Time Scheduling for Linear Model Predictive Control Zhenwu Shi prediction of time-delays caused by real-time scheduling. Then, a model predictive controller is designed, the interaction between real-time scheduling and control design has received interest in the literature

Zhang, Fumin

200

Time series association learning  

DOE Patents [OSTI]

An acoustic input is recognized from inferred articulatory movements output by a learned relationship between training acoustic waveforms and articulatory movements. The inferred movements are compared with template patterns prepared from training movements when the relationship was learned to regenerate an acoustic recognition. In a preferred embodiment, the acoustic articulatory relationships are learned by a neural network. Subsequent input acoustic patterns then generate the inferred articulatory movements for use with the templates. Articulatory movement data may be supplemented with characteristic acoustic information, e.g. relative power and high frequency data, to improve template recognition.

Papcun, George J. (Santa Fe, NM)

1995-01-01T23:59:59.000Z

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


201

On the modeling of time-varying delays  

E-Print Network [OSTI]

This thesis is an effort to develop generalized dynamic models for systems with time-varying time delays. Unlike the simple time-delay model characterized by a transportation lag in the case of a fixed time delay, time-varying delays exhibit quite...

Shah, Chirag Laxmikant

2004-09-30T23:59:59.000Z

202

Concurrency Theory Lecture 22: Timed Modelling & Conclusions  

E-Print Network [OSTI]

Systems Example 22.1 (Real-time reactive systems) brake systems and airbags in cars plant controls mobile.1 (Real-time reactive systems) brake systems and airbags in cars plant controls mobile phones ... Real-Time Reactive Systems Example 22.1 (Real-time reactive systems) brake systems and airbags in cars plant controls

Ábrahám, Erika

203

A component GARCH model with time varying weights  

E-Print Network [OSTI]

2007/19 A component GARCH model with time varying weights Luc Bauwens and Giuseppe Storti #12;CORE DISCUSSION PAPER 2007/19 A component GARCH model with time varying weights Luc BAUWENS1 and Giuseppe STORTI2 March2007 Abstract We present a novel GARCH model that accounts for time varying, state dependent

Nesterov, Yurii

204

A Time Model for Distributed Multimedia Applications  

E-Print Network [OSTI]

properties, using time to specify synchroneity, periodicity, ordering and timeliness. Last but not least objects arriving too late may become useless. Here, time is used to synchronize stream processing, encompassing for example HDTV video streams with a bit rate of up to 2.8 GBit/sec. Media streams have real-time

Kühnhauser, Winfried

205

Intelligent Time-Successive Production Modeling  

E-Print Network [OSTI]

;Background · Production Data Analysis Decline Curve Analysis (Arps, 1945) Type Curve Matching (Fetkovich Analysis Pressure Data + Production Rate Data ·Material Balance methods ·Pseudo time and pseudo pressure

Mohaghegh, Shahab

206

Hierarchical Bayesian models for space-time air pollution data  

E-Print Network [OSTI]

Hierarchical Bayesian models for space-time air pollution data Sujit K. Sahu June 14, 2011 sets have led to a step change in the analysis of space-time air pollution data. Accurate predictions-time air pollution data and illustrate the benefits of modeling with a real data example on monitoring

Sahu, Sujit K

207

Analysis of MALDI FT-ICR Mass Spectrometry Data: a Time Series Donald A. Barkauskasa, Scott R. Kronewitterb, Carlito B. Lebrillab, and David M. Rockec  

E-Print Network [OSTI]

Analysis of MALDI FT-ICR Mass Spectrometry Data: a Time Series Approach Donald A. Barkauskasa/ionization Fourier transform ion cyclotron resonance mass spectrometry is a technique for high mass gamma distribution with varying scale parameter but constant shape parameter and exponent. This enables

Rocke, David M.

208

STAT565: APPLIED TIME SERIES ANALYSIS 16:960:565 SPRING 2014, MONDAY 6:40-9:30 PM, ARC 107 BUS  

E-Print Network [OSTI]

STAT565: APPLIED TIME SERIES ANALYSIS 16:960:565 SPRING 2014, MONDAY 6:40-9:30 PM, ARC 107 BUS 1 or by appointment · Email: hxiao@stat.rutgers.edu · Prerequisite. First graduate level courses in mathematical, by Ruey S. Tsay. Wiley, 2010, 3rd. Full text available from MyiLibrary http://lib.myilibrary.com/Open.aspx?id

Shepp, Larry

209

Handbook of Anatomical Models for Radiation Dosimetry (To be published in 2009 in "Series in Medical Physics and Biomedical Engineering")  

E-Print Network [OSTI]

. George Xu Chapter 24 Nuclear Medicine Imaging and Dosimetry Involving MCAT, NCAT, and MOBY ComputerHandbook of Anatomical Models for Radiation Dosimetry (To be published in 2009 in "Series, USA Preface Chapter 1 Computational Phantoms for Radiation Dosimetry: A 40-Year History of Evolution X

Linhardt, Robert J.

210

Feedback Control RealTime Scheduling: Framework, Modeling, and Algorithms *  

E-Print Network [OSTI]

1 Feedback Control Real­Time Scheduling: Framework, Modeling, and Algorithms * Chenyang Lu John A}@virginia.edu Abstract This paper presents a feedback control real­time scheduling (FCS) framework for adaptive real. In particular, we establish a dynamic model and performance analysis of several feedback control scheduling

Son, Sang H.

211

Feedback Control Real-Time Scheduling: Framework, Modeling, and Algorithms*  

E-Print Network [OSTI]

1 Feedback Control Real-Time Scheduling: Framework, Modeling, and Algorithms* Chenyang Lu John A}@virginia.edu Abstract This paper presents a feedback control real-time scheduling (FCS) framework for adaptive real. In particular, we establish a dynamic model and performance analysis of several feedback control scheduling

Son, Sang H.

212

Classification of $SU(4) \\times SU(2) \\times U(1)$ Heterotic-String Models  

E-Print Network [OSTI]

The free fermionic construction of the heterotic string in four dimensions produced a large space of three generation models with the underlying $SO(10)$ embedding of the Standard Model states. The $SO(10)$ symmetry is broken to a subgroup directly at the string scale. Over the past few years free fermionic models with the Pati-Salam and flipped $SU(5)$ subgroups have been classified. In this paper we extend this classification program to models in which the $SO(10)$ symmetry is broken at the string level to the $SU(4)\\times SU(2)_L\\times U(1)_R$ (SU421) subgroup. The subspace of free fermionic models that we consider corresponds to symmetric ${\\mathbb{Z}}_2 \\times {\\mathbb{Z}}_2$ orbifolds. We provide a general argument that shows that this class of SU421 free fermionic models cannot produce viable three generation models.

Alon E. Faraggi; Hasan Sonmez

2014-12-09T23:59:59.000Z

213

Model checking Timed CSP Philip Armstrong Gavin Lowe Joel Ouaknine  

E-Print Network [OSTI]

Model checking Timed CSP Philip Armstrong Gavin Lowe Jo¨el Ouaknine A.W. Roscoe Oxford University Department of Computer Science Abstract Though Timed CSP was developed 25 years ago and the CSP for Timed CSP. In this paper we report on the creation of such a version, based on the digitisation results

Ouaknine, Joël

214

Modeling and Application of Series Elastic Actuators for Force Control Multi Legged Robots  

E-Print Network [OSTI]

Series Elastic Actuators provide many benefits in force control of robots in unconstrained environments. These benefits include high force fidelity, extremely low impedance, low friction, and good force control bandwidth. Series Elastic Actuators employ a novel mechanical design architecture which goes against the common machine design principal of "stiffer is better". A compliant element is placed between the gear train and driven load to intentionally reduce the stiffness of the actuator. A position sensor measures the deflection, and the force output is accurately calculated using Hooke's Law (F=Kx). A control loop then servos the actuator to the desired output force. The resulting actuator has inherent shock tolerance, high force fidelity and extremely low impedance. These characteristics are desirable in many applications including legged robots, exoskeletons for human performance amplification, robotic arms, haptic interfaces, and adaptive suspensions. We describe several variations of Series Elastic Ac...

S, Arumugom; V, Ponselvan

2009-01-01T23:59:59.000Z

215

Modeling, Safely Advertising and Verifying Time-aware Business Processes  

E-Print Network [OSTI]

Modeling, Safely Advertising and Verifying Time-aware Business Processes : Towards a holistic. Nowadays, the business process model and notation BPMN standard is gaining widspread use in the business, we propose a BPMN extension for capturing temporal requirements during the business process modelling

Paris-Sud XI, Université de

216

Comparing modern and Pleistocene ENSO-like influences in NW Argentina using nonlinear time series analysis methods  

E-Print Network [OSTI]

Higher variability in rainfall and river discharge could be of major importance in landslide generation in the north-western Argentine Andes. Annual layered (varved) deposits of a landslide dammed lake in the Santa Maria Basin (26 deg S, 66 deg W) with an age of 30,000 14C years provide an archive of precipitation variability during this time. The comparison of these data with present-day rainfall observations tests the hypothesis that increased rainfall variability played a major role in landslide generation. A potential cause of such variability is the El Nino/Southern Oscillation (ENSO). The causal link between ENSO and local rainfall is quantified by using a new method of nonlinear data analysis, the quantitative analysis of cross recurrence plots (CRP). This method seeks similarities in the dynamics of two different processes, such as an ocean-atmosphere oscillation and local rainfall. Our analysis reveals significant similarities in the statistics of both modern and palaeo-precipitation data. The similarities in the data suggest that an ENSO-like influence on local rainfall was present at around 30,000 14C years ago. Increased rainfall, which was inferred from a lake balance modeling in a previous study, together with ENSO-like cyclicities could help to explain the clustering of landslides at around 30,000 14C years ago.

N. Marwan; M. H. Trauth; M. Vuille; J. Kurths

2003-03-24T23:59:59.000Z

217

Modeling highway travel time distribution with conditional probability models  

SciTech Connect (OSTI)

ABSTRACT Under the sponsorship of the Federal Highway Administration's Office of Freight Management and Operations, the American Transportation Research Institute (ATRI) has developed performance measures through the Freight Performance Measures (FPM) initiative. Under this program, travel speed information is derived from data collected using wireless based global positioning systems. These telemetric data systems are subscribed and used by trucking industry as an operations management tool. More than one telemetric operator submits their data dumps to ATRI on a regular basis. Each data transmission contains truck location, its travel time, and a clock time/date stamp. Data from the FPM program provides a unique opportunity for studying the upstream-downstream speed distributions at different locations, as well as different time of the day and day of the week. This research is focused on the stochastic nature of successive link travel speed data on the continental United States Interstates network. Specifically, a method to estimate route probability distributions of travel time is proposed. This method uses the concepts of convolution of probability distributions and bivariate, link-to-link, conditional probability to estimate the expected distributions for the route travel time. Major contribution of this study is the consideration of speed correlation between upstream and downstream contiguous Interstate segments through conditional probability. The established conditional probability distributions, between successive segments, can be used to provide travel time reliability measures. This study also suggests an adaptive method for calculating and updating route travel time distribution as new data or information is added. This methodology can be useful to estimate performance measures as required by the recent Moving Ahead for Progress in the 21st Century Act (MAP 21).

Oliveira Neto, Francisco Moraes [ORNL] [ORNL; Chin, Shih-Miao [ORNL] [ORNL; Hwang, Ho-Ling [ORNL] [ORNL; Han, Lee [University of Tennessee, Knoxville (UTK)] [University of Tennessee, Knoxville (UTK)

2014-01-01T23:59:59.000Z

218

Evaluating Wind Power Generating Capacity Adequacy Using MCMC Time Series Model.  

E-Print Network [OSTI]

??In recent decades, there has been a dramatic increase in utilizing renewable energy resources by many power utilities around the world. The tendency toward using… (more)

Almutairi, Abdulaziz

2014-01-01T23:59:59.000Z

219

Desertification of high latitude ecosystems: conceptual models, time-series analyses and experiments  

E-Print Network [OSTI]

of how livestock grazing might initiate early degradation stages, elucidate field-based landscape metrics useful for characterizing degradation stages, and to determine if landscape metrics obtained from remote sensing data can be used to detect landscape...

Thorsson, Johann

2009-05-15T23:59:59.000Z

220

Essays on empirical time series modeling with causality and structural change  

E-Print Network [OSTI]

change in the volatility of five Asian and U.S. stock markets is examined during the post-liberalization period (1990-2005) in the Asian financial markets, using the Sup LM test. Four Asian financial markets (Hong Kong, Japan, Korea, and Singapore...

Kim, Jin Woong

2006-10-30T23:59:59.000Z

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


221

A Time Series Weather Radar Simulator Based on High-Resolution Atmospheric Models  

E-Print Network [OSTI]

to produce theoretical moment maps, which allow for the study of radar characteristics and limitations given of signal-processing techniques, which help identify and scrutinize factors that may have been overlooked corresponding to that spectral shape. Numerous statistical studies were made possible using this simulation

Xue, Ming

222

Statistical Analysis and Time Series Models for Minimum/Maximum Temperatures  

E-Print Network [OSTI]

temperatures, thereby reducing the adverse effect of global warming in the Antarctic Peninsula. Keywords that the observed increase in the minimum temperatures is a consequence of human activity rather than natural causes

Sidorov, Nikita

223

Modeling Gene Regulatory Networks from Time Series Data using Particle Filtering  

E-Print Network [OSTI]

of introducing an L1 norm penalization stems from some inherent short comings associated with an L2 regularization. While L2 regularization provides numerical stability and high delity, it does not encourage 18 a parsimonious description and interpretation...+Lasso True Values EKF PFL b11 3.2 2.8395 3.1471 b12 -4.13 -2.6341 -4.1460 b13 0.02 -10.2405 0.1036 b14 0.02 9.6628 -0.0304 b21 0.01 -1.5092 0.1911 b22 4 2.2126 4.0443 b23 -1.2 11.2065 -1.4836 b24 1.1 -10.4415 1.3312 b31 4.2 4.1983 4.2315 b32 0.02 -0...

Noor, Amina

2012-10-19T23:59:59.000Z

224

Simulation of Water Level Fluctuations in Kettle Holes Using a Time Series Model  

E-Print Network [OSTI]

online: 21 April 2011 # Society of Wetland Scientists 2011 Abstract Kettle holes are widespread in the future, conservation strategies for kettle holes should include the effects of climate change. Keywords). This number is comparable with the wetland loss in the United States (Dahl 1990; Johnston 1994), Japan

Kleyer, Michael

225

A supply forecasting model for Zimbabwe's corn sector: a time series and structural analysis  

E-Print Network [OSTI]

The Zimbabwean government utilizes the corn supply forecasts to establish producer prices for the following growing season, estimate corn storage and handling costs, project corn import needs and associated costs, and to assess the Grain Marketing...

Makaudze, Ephias

1993-01-01T23:59:59.000Z

226

Modeling Space-Time Data Using Stochastic Differential Equations  

E-Print Network [OSTI]

(email: cf.sirmans@business.uconn.edu). The authors thank Thomas Thibodeau for providing the Dallas house ecological process models such as photosynthesis, transpiration, and soil moisture; diffusion models for populations, products or technologies; financial processes such as house price and/or land values over time

Wolpert, Robert L

227

Numerical model of mixed convection heat transfer between a series of vertical parallel plates with planar heat sources  

E-Print Network [OSTI]

Heat transfer between a series of vertical parallel plates with planar heat sources has been studied numerically. The series of plates formed a series of channels, or cooling passages, in which fluid could flow. Heat dissipation from the heat...

Watson, James Christopher

2012-06-07T23:59:59.000Z

228

A case study of an expert mathematics teacher's interactive decision-making system using physiological and behavioral time series data  

E-Print Network [OSTI]

The purpose of this exploratory case study was to describe an expert teacher?s decision-making system during interactive instruction using teacher self-report information, classroom observation data, and physiological recordings. Timed recordings...

Jensen, Deborah Larkey

2005-02-17T23:59:59.000Z

229

Estimation of a Noise Level Using Coarse-Grained Entropy of Experimental Time Series of Internal Pressure in a Combustion Engine  

E-Print Network [OSTI]

We report our results on non-periodic experimental time series of pressure in a single cylinder spark ignition engine. The experiments were performed for different levels of loading. We estimate the noise level in internal pressure calculating the coarse-grained entropy from variations of maximal pressures in successive cycles. The results show that the dynamics of the combustion is a nonlinear multidimensional process mediated by noise. Our results show that so defined level of noise in internal pressure is not monotonous function of loading.

Grzegorz Litak; Rodolfo Taccani; Krzysztof Urbanowicz; Janusz A. Holyst; Miroslaw Wendeker; Alessandro Giadrossi

2004-05-22T23:59:59.000Z

230

Model for LMFBR core transient analysis in real time  

SciTech Connect (OSTI)

Plant safety as well as plant availability can be significantly improved if functions such as data validation, plant state verification, and fault identification are automated. A methodology for automation of these functions was presented in an earlier paper. To implement this methodology, plant models that run significantly faster than real transient time are needed. Such models for the intermediate heat exchanger and a once-through liquid-metal fast breeder reactor (LMFBR) steam generator have been presented. This paper discusses the modeling of LMFBR core transients. It is shown that, with a proper choice of shape functions, a nodal approximation of the coolant, cladding, and fuel temperature distributions leads to adequately accurate power and temperature predictions, as well as adequately short computation times. From the point of view of operational safety, it is desirable to terminate a transient before sodium boiling is initiated in the core. Thus, only the modeling of the preboiling phase of core transients is discussed.

Tzanos, C.P.

1986-01-01T23:59:59.000Z

231

Use of datasets derived from time-series AVHRR imagery as surrogates for land cover maps in predicting species' distributions  

E-Print Network [OSTI]

to be the case, it may be possible to use AVHRR, MODIS, or similar imagery, either in raw form or as easily and cheaply derived datasets, as direct inputs to models that predict species’ distributions. II. METHODS In this pilot analysis, we selected... for Advanced Computational Infrastructure, Earth System Science (NPACI/ESS) Thrust. E.M-M. was supported by a graduate fellowship from the Direccion General de Asuntos del Personal Academico of the National University of Mexico (UNAM...

Egbert, Stephen L.; Martí nez-Meyer, Enrique; Ortega-Huerta, Miguel; Peterson, A. Townsend

2002-06-01T23:59:59.000Z

232

The spherical collapse model in time varying vacuum cosmologies  

E-Print Network [OSTI]

We investigate the virialization of cosmic structures in the framework of flat FLRW cosmological models, in which the vacuum energy density evolves with time. In particular, our analysis focuses on the study of spherical matter perturbations, as they decouple from the background expansion, "turn around" and finally collapse. We generalize the spherical collapse model in the case when the vacuum energy is a running function of the Hubble rate, $\\Lambda=\\Lambda(H)$. A particularly well motivated model of this type is the so-called quantum field vacuum, in which $\\Lambda(H)$ is a quadratic function, $\\Lambda(H)=n_0+n_2\\,H^2$, with $n_0\

S. Basilakos; M. Plionis; J. Sola

2010-09-22T23:59:59.000Z

233

Small-energy series for one-dimensional quantum-mechanical models with non-symmetric potentials  

E-Print Network [OSTI]

We generalize a recently proposed small-energy expansion for one-dimensional quantum-mechanical models. The original approach was devised to treat symmetric potentials and here we show how to extend it to non-symmetric ones. Present approach is based on matching the logarithmic derivatives for the left and right solutions to the Schr\\"odinger equation at the origin (or any other point chosen conveniently) . As in the original method, each logarithmic derivative can be expanded in a small-energy series by straightforward perturbation theory. We test the new approach on four simple models, one of which is not exactly solvable. The perturbation expansion converges in all the illustrative examples so that one obtains the ground-state energy with an accuracy determined by the number of available perturbation corrections.

Paolo Amore; Francisco M. Fernández

2014-10-21T23:59:59.000Z

234

Model for LMFBR core transient analysis in real-time  

SciTech Connect (OSTI)

This paper discusses the modeling of LMFBR core transients. It is shown that with a proper choice of shape functions a nodal approximation of the coolant, cladding, and fuel temperature distributions leads to adequately accurate power and temperature predictions, as well as adequately short computation times.

Tzanos, C.P.

1986-01-01T23:59:59.000Z

235

Time-to-Compromise Model for Cyber Risk Reduction Estimation  

SciTech Connect (OSTI)

We propose a new model for estimating the time to compromise a system component that is visible to an attacker. The model provides an estimate of the expected value of the time-to-compromise as a function of known and visible vulnerabilities, and attacker skill level. The time-to-compromise random process model is a composite of three subprocesses associated with attacker actions aimed at the exploitation of vulnerabilities. In a case study, the model was used to aid in a risk reduction estimate between a baseline Supervisory Control and Data Acquisition (SCADA) system and the baseline system enhanced through a specific set of control system security remedial actions. For our case study, the total number of system vulnerabilities was reduced by 86% but the dominant attack path was through a component where the number of vulnerabilities was reduced by only 42% and the time-to-compromise of that component was increased by only 13% to 30% depending on attacker skill level.

Miles A. McQueen; Wayne F. Boyer; Mark A. Flynn; George A. Beitel

2005-09-01T23:59:59.000Z

236

A Bayesian Bivariate Failure Time Regression Model by Paul Damien  

E-Print Network [OSTI]

. In engineering studies, reliability is defined as the probability that the system has not failed at time t . The reliability of a system using the model in (1) is given by R(t) = P (T 1 ? t; T 2 ? t) = exp(\\Gammaâ??t)[1 using Markov Chain Monte Carlo methods. Keywords: Gumbel Distribution, Gibbs Sampling, Correlation

West, Mike

237

Time-domain simulation of the full hydrodynamic model  

E-Print Network [OSTI]

A simple upwind discretization of the highly coupled non-linear differential equations which define the hydrodynamic model for semiconductors is given in full detail. The hydrodynamic model is able to describe inertia effects which play an increasing role in different fields of opto- and microelectronics. A silicon $n^+ - n - n^+$ - structure is simulated, using the energy-balance model and the full hydrodynamic model. Results for stationary cases are then compared, and it is pointed out where the energy-balance model, which is implemented in most of today's commercial semiconductor device simulators, fails to describe accurately the electron dynamics. Additionally, a GaAs $n^+ - n - n^+$-structure is simulated in time-domain in order to illustrate the importance of inertia effects at high frequencies in modern submicron devices.

Aste, A

2003-01-01T23:59:59.000Z

238

VisIO: enabling interactive visualization of ultra-scale, time-series data via high-bandwidth distributed I/O systems  

SciTech Connect (OSTI)

Petascale simulations compute at resolutions ranging into billions of cells and write terabytes of data for visualization and analysis. Interactive visuaUzation of this time series is a desired step before starting a new run. The I/O subsystem and associated network often are a significant impediment to interactive visualization of time-varying data; as they are not configured or provisioned to provide necessary I/O read rates. In this paper, we propose a new I/O library for visualization applications: VisIO. Visualization applications commonly use N-to-N reads within their parallel enabled readers which provides an incentive for a shared-nothing approach to I/O, similar to other data-intensive approaches such as Hadoop. However, unlike other data-intensive applications, visualization requires: (1) interactive performance for large data volumes, (2) compatibility with MPI and POSIX file system semantics for compatibility with existing infrastructure, and (3) use of existing file formats and their stipulated data partitioning rules. VisIO, provides a mechanism for using a non-POSIX distributed file system to provide linear scaling of 110 bandwidth. In addition, we introduce a novel scheduling algorithm that helps to co-locate visualization processes on nodes with the requested data. Testing using VisIO integrated into Para View was conducted using the Hadoop Distributed File System (HDFS) on TACC's Longhorn cluster. A representative dataset, VPIC, across 128 nodes showed a 64.4% read performance improvement compared to the provided Lustre installation. Also tested, was a dataset representing a global ocean salinity simulation that showed a 51.4% improvement in read performance over Lustre when using our VisIO system. VisIO, provides powerful high-performance I/O services to visualization applications, allowing for interactive performance with ultra-scale, time-series data.

Mitchell, Christopher J [Los Alamos National Laboratory; Ahrens, James P [Los Alamos National Laboratory; Wang, Jun [UCF

2010-10-15T23:59:59.000Z

239

Distinguishing causal time from Minkowski time and a model for the black hole quantum eigenstates  

E-Print Network [OSTI]

A discussion is presented of the principle of black hole com- plementarity. It is argued that this principle could be viewed as a breakdown of general relativity, or alternatively, as the introduction of a time variable with multiple `sheets' or `branches' A consequence of the theory is that the stress-energy tensor as viewed by an outside observer is not simply the Lorentz-transform of the tensor viewed by an ingoing observer. This can serve as a justification of a new model for the black hole atmosphere, recently re-introduced. It is discussed how such a model may lead to a dynamical description of the black hole quantum states.

G. 't Hooft

1997-11-18T23:59:59.000Z

240

Embedded Real-Time Systems Electrical Model Quad Rotor UAV  

E-Print Network [OSTI]

Sys (2013-2014) #12;10 System SW view joystick QR PC link PC lift roll pitch yaw sensorsES joystickIn4073 Embedded Real-Time Systems Electrical Model Quad Rotor UAV #12;2 TE0300 FPGA System HW view), pitch rate (M), and yaw rate (N) (see qrsim for example!) x z y engine 4 engine 3 engine 2 engine 1 In

Langendoen, Koen

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


241

A Comparison of Cosmological Models Using Time Delay Lenses  

E-Print Network [OSTI]

The use of time-delay gravitational lenses to examine the cosmological expansion introduces a new standard ruler with which to test theoretical models. The sample suitable for this kind of work now includes 12 lens systems, which have thus far been used solely for optimizing the parameters of $\\Lambda$CDM. In this paper, we broaden the base of support for this new, important cosmic probe by using these observations to carry out a one-on-one comparison between {\\it competing} models. The currently available sample indicates a likelihood of $\\sim 70-80%$ that the $R_{\\rm h}=ct$ Universe is the correct cosmology versus $\\sim 20-30%$ for the standard model. This possibly interesting result reinforces the need to greatly expand the sample of time-delay lenses, e.g., with the successful implementation of the Dark Energy Survey, the VST ATLAS survey, and the Large Synoptic Survey Telescope. In anticipation of a greatly expanded catalog of time-delay lenses identified with these surveys, we have produced synthetic sa...

Wei, Jun-Jie; Melia, Fulvio

2014-01-01T23:59:59.000Z

242

Models with time-dependent parameters using transform methods: application to Heston's model  

E-Print Network [OSTI]

This paper presents a methodology to introduce time-dependent parameters for a wide family of models preserving their analytic tractability. This family includes hybrid models with stochastic volatility, stochastic interest-rates, jumps and their non-hybrid counterparts. The methodology is applied to Heston's model. A bootstrapping algorithm is presented for calibration. A case study works out the calibration of the time-dependent parameters to the volatility surface of the Eurostoxx 50 index. The methodology is also applied to the analytic valuation of forward start vanilla options driven by Heston's model. This result is used to explore the forward skew of the case study.

Elices, A

2007-01-01T23:59:59.000Z

243

Analysis of real-time reservoir monitoring : reservoirs, strategies, & modeling.  

SciTech Connect (OSTI)

The project objective was to detail better ways to assess and exploit intelligent oil and gas field information through improved modeling, sensor technology, and process control to increase ultimate recovery of domestic hydrocarbons. To meet this objective we investigated the use of permanent downhole sensors systems (Smart Wells) whose data is fed real-time into computational reservoir models that are integrated with optimized production control systems. The project utilized a three-pronged approach (1) a value of information analysis to address the economic advantages, (2) reservoir simulation modeling and control optimization to prove the capability, and (3) evaluation of new generation sensor packaging to survive the borehole environment for long periods of time. The Value of Information (VOI) decision tree method was developed and used to assess the economic advantage of using the proposed technology; the VOI demonstrated the increased subsurface resolution through additional sensor data. Our findings show that the VOI studies are a practical means of ascertaining the value associated with a technology, in this case application of sensors to production. The procedure acknowledges the uncertainty in predictions but nevertheless assigns monetary value to the predictions. The best aspect of the procedure is that it builds consensus within interdisciplinary teams The reservoir simulation and modeling aspect of the project was developed to show the capability of exploiting sensor information both for reservoir characterization and to optimize control of the production system. Our findings indicate history matching is improved as more information is added to the objective function, clearly indicating that sensor information can help in reducing the uncertainty associated with reservoir characterization. Additional findings and approaches used are described in detail within the report. The next generation sensors aspect of the project evaluated sensors and packaging survivability issues. Our findings indicate that packaging represents the most significant technical challenge associated with application of sensors in the downhole environment for long periods (5+ years) of time. These issues are described in detail within the report. The impact of successful reservoir monitoring programs and coincident improved reservoir management is measured by the production of additional oil and gas volumes from existing reservoirs, revitalization of nearly depleted reservoirs, possible re-establishment of already abandoned reservoirs, and improved economics for all cases. Smart Well monitoring provides the means to understand how a reservoir process is developing and to provide active reservoir management. At the same time it also provides data for developing high-fidelity simulation models. This work has been a joint effort with Sandia National Laboratories and UT-Austin's Bureau of Economic Geology, Department of Petroleum and Geosystems Engineering, and the Institute of Computational and Engineering Mathematics.

Mani, Seethambal S.; van Bloemen Waanders, Bart Gustaaf; Cooper, Scott Patrick; Jakaboski, Blake Elaine; Normann, Randy Allen; Jennings, Jim (University of Texas at Austin, Austin, TX); Gilbert, Bob (University of Texas at Austin, Austin, TX); Lake, Larry W. (University of Texas at Austin, Austin, TX); Weiss, Chester Joseph; Lorenz, John Clay; Elbring, Gregory Jay; Wheeler, Mary Fanett (University of Texas at Austin, Austin, TX); Thomas, Sunil G. (University of Texas at Austin, Austin, TX); Rightley, Michael J.; Rodriguez, Adolfo (University of Texas at Austin, Austin, TX); Klie, Hector (University of Texas at Austin, Austin, TX); Banchs, Rafael (University of Texas at Austin, Austin, TX); Nunez, Emilio J. (University of Texas at Austin, Austin, TX); Jablonowski, Chris (University of Texas at Austin, Austin, TX)

2006-11-01T23:59:59.000Z

244

Multiple-relaxation-time lattice Boltzmann kinetic model for combustion  

E-Print Network [OSTI]

To probe both the Mechanical Non-Equilibrium (MNE) and Thermodynamic Non-Equilibrium (TNE) in the combustion procedure, a two-dimensional Multiple-Relaxation-Time (MRT) version of the Lattice Boltzmann Kinetic Model(LBKM) for combustion phenomena is presented. The chemical energy released in the progress of combustion is dynamically coupled into the system by adding a chemical term to the LB kinetic equation. The LB model is required to recover the Navier-Stokes equations with chemical reaction in the hydrodynamic limit. To that aim, we construct a discrete velocity model with $24$ velocities divided into $3$ groups. In each group a flexible parameter is used to control the size of discrete velocities and a second parameter is used to describe the contribution of the extra degrees of freedom. The current model works for both subsonic and supersonic flows with or without chemical reaction. In this model both the specific-heat ratio and the Prandtl number are flexible, the TNE effects are naturally presented in each simulation step. Via the MRT model, it is more convenient to track the effects of TNE and how the TNE influence the MNE behaviors. The model is verified and validated via well-known benchmark tests. It is found that around the detonation wave there are competition between the viscous effect, thermal diffusion effect and the gradient effects of physical quantities. Consequently, with decreasing the collision parameters, (i) the nonequilibrium region becomes wider and the gradients of physical quantities decrease; (ii) the position where the internal energy in the shocking degree of freedom equals the one averaged over all degrees of freedom moves away from the position for the von Neumann peak.

Aiguo Xu; Chuandong Lin; Guangcai Zhang; Yingjun Li

2014-11-25T23:59:59.000Z

245

Multiple-relaxation-time lattice Boltzmann kinetic model for combustion  

E-Print Network [OSTI]

To probe both the Hydrodynamic Non-Equilibrium (HNE) and Thermodynamic Non-Equilibrium (TNE) in the combustion process, a two-dimensional Multiple-Relaxation-Time (MRT) version of Lattice Boltzmann Kinetic Model(LBKM) for combustion phenomena is presented. The chemical energy released in the progress of combustion is dynamically coupled into the system by adding a chemical term to the LB kinetic equation. Beside describing the evolutions of the conserved quantities, the density, momentum and energy, which are what the Navier-Stokes model describes, the MRT-LBKM presents also a coarse-grained description on the evolutions of some non-conserved quantities. The current model works for both subsonic and supersonic flows with or without chemical reaction. In this model both the specific-heat ratio and the Prandtl number are flexible, the TNE effects are naturally presented in each simulation step. The model is verified and validated via well-known benchmark tests. As an initial application, various non-equilibrium behaviours, including the complex interplays between various HNEs, between various TNEs and between the HNE and TNE, around the detonation wave in the unsteady and steady one-dimensional detonation processes are preliminarily probed. It is found that the system viscosity (or heat conductivity) decreases the local TNE, but increase the global TNE around the detonation wave, that even locally, the system viscosity (or heat conductivity) results in two kinds of competing trends, to increase and to decrease the TNE effects. The physical reason is that the viscosity (or heat conductivity) takes part in both the thermodynamic and hydrodynamic responses.

Aiguo Xu; Chuandong Lin; Guangcai Zhang; Yingjun Li

2015-03-13T23:59:59.000Z

246

Accelerated Failure Time Regression Model with a Regression Model of Surviving Fraction: An Application to the Analysis of RPermanent EmploymentS in Japan  

E-Print Network [OSTI]

other hand, for any given accelerated failure-time model, weconsidered improvements of accelerated failure-time models.Although representative accelerated failure-time models can

Kazuo Yamaguchi

2011-01-01T23:59:59.000Z

247

$J/?$ suppression in the threshold model and QGP formation time  

E-Print Network [OSTI]

In the QGP motivated threshold model, in addition to the normal nuclear absorption, $J/\\psi$'s are subjected to an additional "anomalous" suppression. We have analysed the recently published PHENIX data on the participant number dependence of the nuclear modification factor for $J/\\psi$'s in Au+Au collisions and extracted the anomalous suppression required to explain the data. At mid rapidity $J/\\psi$'s are anomalously suppressed only above a threshold density $n_c$=3.73 fm$^{-2}$. The forward rapidity data on the otherhand require that $J/\\psi$'s are continuously "anomalously" suppressed. The analysis strongly indicate that in mid rapidity $J/\\psi$'s are suppressed in a deconfined medium. Using the PHENIX data on the participant number dependence of the Bjorken energy density, we have also estimated the QGP formation time. For critical temperature $T_c$=192 MeV, estimated QGP formation time ranges between 0.06-0.08 fm/c.

A. K. Chaudhuri

2007-09-03T23:59:59.000Z

248

TIME-SERIES PHOTOMETRY OF GLOBULAR CLUSTERS: M62 (NGC 6266), THE MOST RR LYRAE-RICH GLOBULAR CLUSTER IN THE GALAXY?  

SciTech Connect (OSTI)

We present new time-series CCD photometry, in the B and V bands, for the moderately metal-rich ([Fe/H] {approx_equal} -1.3) Galactic globular cluster M62 (NGC 6266). The present data set is the largest obtained so far for this cluster and consists of 168 images per filter, obtained with the Warsaw 1.3 m telescope at the Las Campanas Observatory and the 1.3 m telescope of the Cerro Tololo Inter-American Observatory, in two separate runs over the time span of 3 months. The procedure adopted to detect the variable stars was the optimal image subtraction method (ISIS v2.2), as implemented by Alard. The photometry was performed using both ISIS and Stetson's DAOPHOT/ALLFRAME package. We have identified 245 variable stars in the cluster fields that have been analyzed so far, of which 179 are new discoveries. Of these variables, 133 are fundamental mode RR Lyrae stars (RRab), 76 are first overtone (RRc) pulsators, 4 are type II Cepheids, 25 are long-period variables (LPVs), 1 is an eclipsing binary, and 6 are not yet well classified. Such a large number of RR Lyrae stars places M62 among the top two most RR Lyrae-rich (in the sense of total number of RR Lyrae stars present) globular clusters known in the Galaxy, second only to M3 (NGC 5272) with a total of 230 known RR Lyrae stars. Since this study covers most but not all of the cluster area, it is not unlikely that M62 is in fact the most RR Lyrae-rich globular cluster in the Galaxy. In like vein, thanks to the time coverage of our data sets, we were also able to detect the largest sample of LPVs known so far in a Galactic globular cluster. We analyze a variety of Oosterhoff type indicators for the cluster, including mean periods, period distribution, Bailey diagrams, and Fourier decomposition parameters (as well as the physical parameters derived therefrom). All of these indicators clearly show that M62 is an Oosterhoff type I system. This is in good agreement with the moderately high metallicity of the cluster, in spite of its predominantly blue horizontal branch morphology-which is more typical of Oosterhoff type II systems. We thus conclude that metallicity plays a key role in defining Oosterhoff type. Finally, based on an application of the 'A-method', we conclude that the cluster RR Lyrae stars have a similar He abundance as M3, although more work on the temperatures of the M62 RR Lyrae is needed before this result can be conclusively established.

Contreras, R. [INAF-Osservatorio Astronomico di Bologna, via Ranzani 1, 40127, Bologna (Italy); Catelan, M. [Departamento de AstronomIa y Astrofisica, Pontificia Universidad Catolica de Chile, Av. Vicuna Mackenna 4860, 782-0436 Macul, Santiago (Chile); Smith, H. A.; Kuehn, C. A. [Department of Physics and Astronomy, Michigan State University, East Lansing, MI 48824 (United States); Pritzl, B. J. [Department of Physics and Astronomy, University of Wisconsin, Oshkosh, WI 54901 (United States); Borissova, J. [Departamento de Fisica y AstronomIa, Facultad de Ciencias, Universidad de ValparaIso, Ave. Gran Bretana 1111, Playa Ancha, Casilla 5030, ValparaIso (Chile)

2010-12-15T23:59:59.000Z

249

Abarbanel, H., Brown, R., & Kadtke, J., 1989. Prediction and System Iden tification in Chaotic Time Series with Broadband Fourier Spectra. Phys.  

E-Print Network [OSTI]

Preprint Series LSE­MPS­67, Dept. of Mathematics, London School of Economics, Houghton St., London WC2A 2AE experiments on identification of transmembrane domains. In Proceedings of the 25th Hawaii International

Schuurmans, Dale

250

First-time measurements will advance turbulence models  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsruc DocumentationP-Series toESnet4:EpitaxialtransatlanticUnified|North Americacollaborative

251

Modeling Metal Fatigue As a Key Step in PV Module Life Time Prediction (Presentation)  

SciTech Connect (OSTI)

This presentation covers modeling metal fatigue as a key step in photovoltaic (PV) module lifetime predictions. Described are time-dependent and time-independent case studies.

Bosco, N.

2012-02-01T23:59:59.000Z

252

The Continuous Cross-Nested Logit Model: Formulation and Application for Departure Time Choice  

E-Print Network [OSTI]

The Continuous Cross-Nested Logit Model: Formulation and Application for Departure Time Choice modeling, departure time modeling, continuous logit, continuous cross- nested logit, Bayesian estimation usage). In this paper, the continuous cross-nested logit (CCNL) model is introduced. The CCNL model

Kockelman, Kara M.

253

Time Dependent Hadronic Modeling of Flat Spectrum Radio Quasars  

E-Print Network [OSTI]

We introduce a new time-dependent lepto-hadronic model for blazar emission that takes into account the radiation emitted by secondary particles, such as pions and muons, from photo hadronic interactions. Starting from a baseline parameter set guided by a fit to the spectral energy distribution of the blazar 3C 279, we perform a parameter study to investigate the effects of perturbations of the input parameters to mimic different flaring events to study the resulting lightcurves in the optical, X-ray, high energy (HE: E > 100 MeV) and very-high-energy (VHE: E > 100 GeV) gamma-rays as well as the neutrino emission associated with charged-pion and muon decay. We find that flaring events from an increase in the efficiency of Fermi II acceleration will produce a positive correlation between all bandpasses and a marked plateau in the HE gamma-ray lightcurve. We also predict a distinctive dip in the HE lightcurve for perturbations caused by a change in the proton injection spectral index. These plateaus / dips could...

Diltz, Christopher; Fossati, Giovanni

2015-01-01T23:59:59.000Z

254

Bayesian Estimation of a Continuous-Time Model for Discretely-Observed Panel Data  

E-Print Network [OSTI]

Continuous-time models are used in many areas of science. However, in psychology and related fields, continuous-time models are often difficult to apply because only a small number of repeated observations are typically ...

Boulton, Aaron Jacob

2014-08-31T23:59:59.000Z

255

Real-Time Ensemble Control with Reduced-Order Modeling  

E-Print Network [OSTI]

The control of spatially distributed systems is often complicated by significant uncertainty about system inputs, both time-varying exogenous inputs and time-invariant parameters. Spatial variations of uncertain parameters ...

Lin, Binghuai

256

Towards a Times-Based Usage Control Model Baoxian Zhao1  

E-Print Network [OSTI]

Towards a Times-Based Usage Control Model Baoxian Zhao1 , Ravi Sandhu2 , Xinwen Zhang3 usage of digital objects. To meet these requirements, we pre- sent a new access control model­Times-based Usage Control (TUCON). TUCON extends traditional and temporal access control models with times

Sandhu, Ravi

257

Resumming the string perturbation series  

E-Print Network [OSTI]

We use the AdS/CFT correspondence to study the resummation of a perturbative genus expansion appearing in the type II superstring dual of ABJM theory. Although the series is Borel summable, its Borel resummation does not agree with the exact non-perturbative answer due to the presence of complex instantons. The same type of behavior appears in the WKB quantization of the quartic oscillator in Quantum Mechanics, which we analyze in detail as a toy model for the string perturbation series. We conclude that, in these examples, Borel summability is not enough for extracting non-perturbative information, due to non-perturbative effects associated to complex instantons. We also analyze the resummation of the genus expansion for topological string theory on local $\\mathbb P^1 \\times \\mathbb P^1$, which is closely related to ABJM theory. In this case, the non-perturbative answer involves membrane instantons computed by the refined topological string, which are crucial to produce a well-defined result. We give evidence that the Borel resummation of the perturbative series requires such a non-perturbative sector.

Alba Grassi; Marcos Marino; Szabolcs Zakany

2015-02-10T23:59:59.000Z

258

Timed Automata Lecture #15 of Advanced Model Checking  

E-Print Network [OSTI]

controller of an airplane, railway crossing, robot controllers ­ steel production controllers, communication ­ the next-operator "measures" time passage ­ two time units after being red, the light is green: 2 (red green) ­ within two time units after red, the light is green: 2 (red (green green green)) 2 green

Ábrahám, Erika

259

Timed Automata Lecture #15 of Advanced Model Checking  

E-Print Network [OSTI]

of an airplane, railway crossing, robot controllers ­ steel production controllers, communication protocols ­ the next-operator "measures" time passage ­ two time units after being red, the light is green: 2 (red green) ­ within two time units after red, the light is green: 2 (red (green green green)) | {z } 2

Ábrahám, Erika

260

UCLA space-time area law model: A persuasive foundation for hadronization  

E-Print Network [OSTI]

UCLA-HEP-06-001 UCLA space-time area law model: A persuasivedominantly controlled by a Space- Time Area Law (“STAL”), anheavy quarks whose classical space-time world-lines deviate

Abachi, S; Buchanan, C; Chien, A; Chun, S; Hartfiel, B

2007-01-01T23:59:59.000Z

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


261

A New Approach to Fuzzy Modeling and Control of Discrete-Time Systems  

E-Print Network [OSTI]

], the advantage of fuzzy logic in modeling and control is in the ability to combine modeling (constructingA New Approach to Fuzzy Modeling and Control of Discrete-Time Systems Michael Margaliot and Gideon Langholz #3; Abstract We present a new approach to fuzzy modeling and control of discrete-time sys- tems

Margaliot, Michael

262

A Survey on Time-aware Business Process Modeling Saoussen Cheikhrouhou1  

E-Print Network [OSTI]

A Survey on Time-aware Business Process Modeling Saoussen Cheikhrouhou1 , Slim Kallel1 , Nawal : Business Process Modeling (BPM) : Workflow : Web service composition : Inter-Organisational Business suites. Consequently, modeling and managing temporal requirements in the business process field

Paris-Sud XI, Université de

263

A Generic Space-Time-Frequency Correlation Model and Its Corresponding Simulation Model for Narrowband MIMO Channels  

E-Print Network [OSTI]

A Generic Space-Time-Frequency Correlation Model and Its Corresponding Simulation Model.Laurenson d9ed. ac. uk Keyword: Wireless channels, NIIMO, STF correlation, deterministic simulation model theoretical reference model, a deterministic simulation model is then proposed and its 3-D STF correlation

Wang, Cheng-Xiang

264

Probabilistic Modeling of Runway Inter-departure Times Ioannis Simaiakis  

E-Print Network [OSTI]

International Airport (BOS) for the 22L, 27 | 22L, 22R runway configuration in 2011. III. Estimation of service to both the modeling of airport operations, and to the estimation of airport capacities. II. Data sources threshold [8]. The Airport Surface Detection Equipment ­ Model X (ASDE-X) system combines data from surface

Gummadi, Ramakrishna

265

Time-series analysis for the episodic production and transport of methane from the Glacial Lake Agassiz peatlands, northern Minnesota. Final report  

SciTech Connect (OSTI)

The large peat basins of North America are an important reservoir in the global carbon cycle and a significant source of atmospheric methane. The authors investigated carbon cycling in the Glacial Lake Agassiz peatlands (GLAP) of Minnesota. Initially in 1990, they identified a dramatic change in the concentration of methane in the pore-waters of the raised bogs in the GLAP during an extreme drought. This methane dissipated when the drought broke in 1991 and the occurrence of deep methane is related to changes in the direction of groundwater flow in the peat column. The production of methane and its diffusive loss to the atmosphere was modeled and was about 10 times less than that measured directly in chambers at the land surface. It is clear from the reversals in hydraulic heat, changes in pore-water chemical composition over time, and paleostratigraphic markers, that regional ground water flow systems that are controlled by climate change are unexpectedly a major control over methanogenesis and carbon cycling in GLAP. Seismic profiles made showed that buried bedrock ridges particularly deflect regional groundwater flow upwards towards the land surface and towards raised bog landforms. In addition, high-resolution GPS measurements from data stations funded by this DOE project have shown this year that the peakland land surface elevation changes daily on a scale of cms, and seasonally on a scale of 10s of cm. This most recent observation is exciting because it may reflect episodic degassing of free phase methane from the peat column to the atmosphere, a source for methane previously unaccounted for by methane researchers.

Siegel, D.I.

1998-01-01T23:59:59.000Z

266

A MACHINE LEARNING APPROACH TO QUERY TIME-SERIES MICROARRAY DATA SETS FOR FUNCTIONALLY RELATED GENES USING HIDDEN MARKOV MODELS  

E-Print Network [OSTI]

Microarray technology captures the rate of expression of genes under varying experimental conditions. Genes encode the information necessary to build proteins; proteins used by cellular functions exhibit higher rates of ...

Senf, Alexander J.

2011-02-04T23:59:59.000Z

267

Hierarchical Bivariate Time Series Models: A Combined Analysis of the Effects of Particulate Matter on Morbidity and  

E-Print Network [OSTI]

manufacturers. Funding for Francesca Dominici was provided by a grant from the Health Effects Institute (Walter Effects Institute (HEI), an organization jointly funded by the Environmental Protection Agency (EPA R@jhsph.edu. Acknowledgments: Research described in this article was partially supported by a contract and grant from Health

Dominici, Francesca

268

Multi-horizon solar radiation forecastingfor Mediterranean locations using time series models Cyril Voyant1,2*  

E-Print Network [OSTI]

energy sources, which one of the main advantages is the renewable and inexhaustible aspects and the main the resource to manage the transition between different energies sources and store the energy excess of the renewable energy sources. The optimizationand the management of energy system are really a challenging issue

Paris-Sud XI, Université de

269

Space and Time: Wind in an Investment Planning Model  

E-Print Network [OSTI]

in different regions. Given the stock of existing capacity and the new investment the model then solves for the cheapest way to dispatch the system to satisfy demand. This could also involve demand side response, which we currently model to be avail- able... , generation and wind data as described in the previous section. The model then calculates the forward looking least cost invest- ment and operation plan to serve demand. Figure 4 illustrates the resulting cumulative new build in each of the regions. 10...

Neuhoff, Karsten; Ehrenmann, A; Butler, Lucy; Cust, J; Hoexter, Harriet; Keats, Kim; Kreczko, Adam; Sinden, Graham

2006-03-14T23:59:59.000Z

270

ASYMPTOTIC DISTRIBUTION OF ESTIMATES FOR A TIME-VARYING PARAMETER IN A HARMONIC MODEL  

E-Print Network [OSTI]

ASYMPTOTIC DISTRIBUTION OF ESTIMATES FOR A TIME-VARYING PARAMETER IN A HARMONIC MODEL WITH MULTIPLE harmonic regression models are useful for cases where harmonic parameters appear to be time-varying. Least, harmonic regression, signal processing, sound analysis, time-varying parameters, weighted least squares

Irizarry, Rafael A.

271

An integrated system for real-time Model Predictive Control of humanoid robots  

E-Print Network [OSTI]

this goal. The automatic controller is based on real-time model-predictive control (MPC) applied to the full. The resulting composite cost is sent to the MPC machinery which constructs a new locally-optimal time- varying-based optimal control is called Model-Predictive Control (MPC), an approach that relies on real-time trajectory

Todorov, Emanuel

272

SCIA 2003 Tutorial: Hidden Markov Models  

E-Print Network [OSTI]

SCIA 2003 Tutorial: Hidden Markov Models Sam Roweis, University of Toronto June 29, 2003 Probabilistic Generative Models for Time Series · Stochastic models for time-series: y1, y2, . . . , yT To get the system stochastic: p(yt|yt-1, yt-2, . . . , yt-k) · Markov models have two problems: ­ need big order

Roweis, Sam

273

A time varying GARCH (p, q) model and related statistical inference  

E-Print Network [OSTI]

A time varying GARCH (p, q) model and related statistical inference Technical Report No: ISINE Institute North-East Centre, Tezpur, Assam-784028 #12;A time varying GARCH (p, q) model and related varying GARCH (tvGARCH (p, q)) model and consider certain related inferential problems. A two-step local

Bandyopadhyay, Antar

274

Toward a Time-centric modeling of Business Processes in BPMN 2.0  

E-Print Network [OSTI]

Toward a Time-centric modeling of Business Processes in BPMN 2.0 Saoussen Cheikhrouhou Re, regulatory, and managerial rules. One of the most promising standards for business process model- ing, namely the Business process Model and notation BPMN poorly addresses the time dimension so far. In this paper, we

Paris-Sud XI, Université de

275

A MODEL FOR THE FLEET SIZING OF DEMAND RESPONSIVE TRANSPORTATION SERVICES WITH TIME WINDOWS  

E-Print Network [OSTI]

A MODEL FOR THE FLEET SIZING OF DEMAND RESPONSIVE TRANSPORTATION SERVICES WITH TIME WINDOWS Marco a demand responsive transit service with a predetermined quality for the user in terms of waiting time models; Continuous approximation models; Paratransit services; Demand responsive transit systems. #12;3 1

Dessouky, Maged

276

Fast Seismic Modeling and Reverse Time Migration on a GPU Cluster R. Abdelkhalek1  

E-Print Network [OSTI]

Fast Seismic Modeling and Reverse Time Migration on a GPU Cluster R. Abdelkhalek1 , H. Calandra1 equation in an oil exploration industrial context aims at speeding up seismic modeling and Reverse Time application over a sequential code running on general purpose CPU. KEYWORDS: Seismic modeling, Finite

Paris-Sud XI, Université de

277

Three-dimensional finite difference time domain modeling of the Earth-ionosphere cavity resonances  

E-Print Network [OSTI]

domain (FDTD) model of Schumann resonances (SR) with a set of classical eigenfrequency and quality factorThree-dimensional finite difference time domain modeling of the Earth-ionosphere cavity resonances-dimensional finite difference time domain modeling of the Earth-ionosphere cavity resonances, Geophys. Res. Lett., 32

Pasko, Victor

278

Extending Qualitative Modelling for Simulation of TimeDelayed Behaviour  

E-Print Network [OSTI]

industrial plants is to choose a measured variable and maintain the re­ quired value of this variable through a process of mea­ surement, comparison, and adjustment. A time delay between a disturbance in the plant applicable to simulators that enable synchronous tracking. The rest of this paper is arranged as follows

Miguel, Ian

279

Development of a real-time quantitative hydrologic forecasting model  

E-Print Network [OSTI]

TIME ) Ftgure 2. porno(lal f loni daaaga reduction aada possible hy a gives ruspanav ties (acr rrata forecast Ivad (Iacl. The do(ted ll?es In tha figure gives wt essnple uhlclt ahoun that as tha fnrecast land tlaa Incrva. as frua 4 to l4 hours...

Bell, John Frank

1986-01-01T23:59:59.000Z

280

A Model for Minimizing Active Processor Time Jessica Chang1  

E-Print Network [OSTI]

, the problem often becomes NP-complete.) We propose a simple model for measuring energy usage on a parallel consumes a fixed amount of energy per active timeslot, regardless of the number of jobs scheduled to finding a triangle-free 2-matching on a special graph. We extend the algorithm of Babenko et. al. [3

Khuller, Samir

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


281

A Model for Minimizing Active Processor Time Jessica Chang  

E-Print Network [OSTI]

#12;We propose a simple model for measuring energy usage on a parallel machine. Rather than focusing consumes a fixed amount of energy per active timeslot, regardless of the number of jobs scheduled, the problem amounts to finding a triangle-free 2-matching on a special graph. We extend the algorithm

Khuller, Samir

282

A FINITE ELEMENT MODEL FOR THE TIME-DEPENDENT JOULE HEATING PROBLEM*  

E-Print Network [OSTI]

.3) 0 system models the electric heating* *ial differential equation describing the electric heating of a conducting body. We prove err* *or A FINITE ELEMENT MODEL FOR THE TIME-DEPENDENT JOULE HEATING PROBLEM

Larsson, Stig

283

A System-Level Electrostatic-Discharge-Protection Modeling Methodology for Time-  

E-Print Network [OSTI]

A System-Level Electrostatic-Discharge- Protection Modeling Methodology for Time- Domain Analysis. Index Terms--Electromagnetic compatibility (EMC), electrostatic discharge (ESD), modeling, system level precise simulations of electrostatic discharge (ESD) stress propagation on a printed circuit board (PCB

Boyer, Edmond

284

About model of the Universe with accelerated movement of the time  

E-Print Network [OSTI]

Cosmological model based on metric of Fridmann-Robertson-Walker with permanent size and acceleration of time is considered. The problem of the dark matter is analyzed within this model .

W. B. Belayev

1999-03-30T23:59:59.000Z

285

Effectiveness of 4D construction modeling in detecting time-space conflicts of construction sites  

E-Print Network [OSTI]

This research investigated whether 4D construction model effectively helps project participants on construction sites in detecting time-space conflicts in the schedule. Previous researchers on construction space management typically modeled space...

Nigudkar, Narendra Shriniwas

2005-11-01T23:59:59.000Z

286

Method of modeling transmissions for real-time simulation  

DOE Patents [OSTI]

A transmission modeling system includes an in-gear module that determines an in-gear acceleration when a vehicle is in gear. A shift module determines a shift acceleration based on a clutch torque when the vehicle is shifting between gears. A shaft acceleration determination module determines a shaft acceleration based on at least one of the in-gear acceleration and the shift acceleration.

Hebbale, Kumaraswamy V.

2012-09-25T23:59:59.000Z

287

Evaluation of scalar mixing and time scale models in PDF simulations of a turbulent premixed flame  

SciTech Connect (OSTI)

Numerical simulation results obtained with a transported scalar probability density function (PDF) method are presented for a piloted turbulent premixed flame. The accuracy of the PDF method depends on the scalar mixing model and the scalar time scale model. Three widely used scalar mixing models are evaluated: the interaction by exchange with the mean (IEM) model, the modified Curl's coalescence/dispersion (CD) model and the Euclidean minimum spanning tree (EMST) model. The three scalar mixing models are combined with a simple model for the scalar time scale which assumes a constant C{sub {phi}}=12 value. A comparison of the simulation results with available measurements shows that only the EMST model calculates accurately the mean and variance of the reaction progress variable. An evaluation of the structure of the PDF's of the reaction progress variable predicted by the three scalar mixing models confirms this conclusion: the IEM and CD models predict an unrealistic shape of the PDF. Simulations using various C{sub {phi}} values ranging from 2 to 50 combined with the three scalar mixing models have been performed. The observed deficiencies of the IEM and CD models persisted for all C{sub {phi}} values considered. The value C{sub {phi}}=12 combined with the EMST model was found to be an optimal choice. To avoid the ad hoc choice for C{sub {phi}}, more sophisticated models for the scalar time scale have been used in simulations using the EMST model. A new model for the scalar time scale which is based on a linear blending between a model for flamelet combustion and a model for distributed combustion is developed. The new model has proven to be very promising as a scalar time scale model which can be applied from flamelet to distributed combustion. (author)

Stoellinger, Michael; Heinz, Stefan [Department of Mathematics, University of Wyoming, Laramie, WY (United States)

2010-09-15T23:59:59.000Z

288

Department of Electrical and Computer Engineering Fall 2011 Seminar Series  

E-Print Network [OSTI]

transcription requires the understanding of cooperative regulations by TFs and miRNAs, which however haveDepartment of Electrical and Computer Engineering Fall 2011 Seminar Series Seminar Title: Uncover context-specific co-regulations by transcription factors and microRNAs using Bayesian factor model Time

Pal, Ranadip

289

Statistical testing and estimation in continuous time interest rate models  

E-Print Network [OSTI]

. In such a case, the power of the test does not tend to one in spite of large sample sizes. On the other hand, the consistent nonparametric tests avoid this problem. To test the correctness of a parametric model, say, Yi = l(xti ;?) + ei, we can consider.... In practice, we use ^i in lieu of ei, where ^i = Yi ? l(xti ; ^) is a residual, and ^ is 11 an OLS estimator of ? and Yi is a response variable. Using the leave one out kernel estimator 1nh Pnj6=i ^jk(xtj ?xtih ), the test statistic stems from the following...

Kim, Myung Suk

2006-10-30T23:59:59.000Z

290

Real-time capable first principle based modelling of tokamak turbulent transport  

E-Print Network [OSTI]

A real-time capable core turbulence tokamak transport model is developed. This model is constructed from the regularized nonlinear regression of quasilinear gyrokinetic transport code output. The regression is performed with a multilayer perceptron neural network. The transport code input for the neural network training set consists of five dimensions, and is limited to adiabatic electrons. The neural network model successfully reproduces transport fluxes predicted by the original quasilinear model, while gaining five orders of magnitude in computation time. The model is implemented in a real-time capable tokamak simulator, and simulates a 300s ITER discharge in 10s. This proof-of-principle for regression based transport models anticipates a significant widening of input space dimensionality and physics realism for future training sets. This aims to provide unprecedented computational speed coupled with first-principle based physics for real-time control and integrated modelling applications.

Breton, S; Felici, F; Imbeaux, F; Aniel, T; Artaud, J F; Baiocchi, B; Bourdelle, C; Camenen, Y; Garcia, J

2015-01-01T23:59:59.000Z

291

From Jammer to Gambler: Modeling and Detection of Jamming Attacks against Time-Critical Traffic  

E-Print Network [OSTI]

From Jammer to Gambler: Modeling and Detection of Jamming Attacks against Time-Critical Traffic attacks. However, existing methods to characterize and detect jamming attacks cannot be applied directly. In this paper, we aim at modeling and detecting jamming attacks against time-critical traffic. We introduce

Wang, Wenye

292

Dynamic Optimization in Continuous-Time Economic Models (A Guide for the Perplexed)  

E-Print Network [OSTI]

Dynamic Optimization in Continuous-Time Economic Models (A Guide for the Perplexed) Maurice, continuous-time modeling allows application of a powerful mathematical tool, the theory of optimal dynamic control. The basic idea of optimal control theory is easy to grasp-- indeed it follows from elementary

Sadoulet, Elisabeth

293

Time-Varying FOPDT Modeling and On-line Parameter Identification  

E-Print Network [OSTI]

dynamic modeling in a supermarket refrigeration system. Keywords: System identification, FOPDT, time in a refrigeration system. The TV-FOPDT model is an extension of the standard FOPDT by allowing the system parameters. The proposed approaches can simultaneously estimate the time-dependent system parameters, as well

Yang, Zhenyu

294

Multiagent Bayesian Forecasting of Structural Time-Invariant Dynamic Systems with  

E-Print Network [OSTI]

. Alternatively, time series are represented by state-space models, also referred to as multivariate dynamic and science. We study forecasting of stochastic, dynamic systems based on observations from multivariate time to a discrete time, multivariate time series [1, 2]. The primary inference that we address is one- step

Xiang, Yang

295

SPACE-TIME BLOCK CODING : JOINT DETECTION AND CHANNEL ESTIMATION USING MULTIPLE MODEL THEORY  

E-Print Network [OSTI]

SPACE-TIME BLOCK CODING : JOINT DETECTION AND CHANNEL ESTIMATION USING MULTIPLE MODEL THEORY Harini of Sheffield, Mappin Street, Sheffield S1 3JD. Email: visakan@sheffield.ac.uk ABSTRACT A joint decoding method for space-time block codes [1, 2] is pre- sented. The space-time coded signals can be viewed as a first

Imperial College, London

296

Driver Models For Timing And Noise Analysis Bogdan Tutuianu and Ross Baldick  

E-Print Network [OSTI]

Driver Models For Timing And Noise Analysis Bogdan Tutuianu and Ross Baldick Abstract errors. This paper presents a new technique to generate accurate non-linear driver models which can driver is holding low or high, the driver is correctly approximated by a linear (RC) model

Baldick, Ross

297

A Mixed Model for Real-Time, Interactive Simulation of a Cable Passing Through Several Pulleys  

SciTech Connect (OSTI)

A model of a cable and pulleys is presented that can be used in Real Time Computer Graphics applications. The model is formulated by the coupling of a damped spring and a variable coefficient wave equation, and can be integrated in more complex mechanical models of lift systems, such as cranes, elevators, etc. with a high degree of interactivity.

Garcia-Fernandez, Ignacio; Pla-Castells, Marta; Martinez-Dura, Rafael J. [Instituto de Robotica. Universidad de Valencia (Spain)

2007-09-06T23:59:59.000Z

298

Current Theoretical Models and Future High Resolution Solar Observations: Preparing for ATST ASP Conference Series, Vol. ???, 2002  

E-Print Network [OSTI]

Observatory, China derived with a solar scintillometer (Seykora 1992) and a Solar Differential Image MotionCurrent Theoretical Models and Future High Resolution Solar Observations: Preparing for ATST ASP-Site Observatory Carsten Denker New Jersey Institute of Technology, Center for Solar Research 323 Martin Luther

299

Comparative Studies of Clustering Techniques for Real-Time Dynamic Model Reduction  

E-Print Network [OSTI]

Dynamic model reduction in power systems is necessary for improving computational efficiency. Traditional model reduction using linearized models or offline analysis would not be adequate to capture power system dynamic behaviors, especially the new mix of intermittent generation and intelligent consumption makes the power system more dynamic and non-linear. Real-time dynamic model reduction emerges as an important need. This paper explores the use of clustering techniques to analyze real-time phasor measurements to determine generator groups and representative generators for dynamic model reduction. Two clustering techniques -- graph clustering and evolutionary clustering -- are studied in this paper. Various implementations of these techniques are compared and also compared with a previously developed Singular Value Decomposition (SVD)-based dynamic model reduction approach. Various methods exhibit different levels of accuracy when comparing the reduced model simulation against the original model. But some ...

Hogan, Emilie; Halappanavar, Mahantesh; Huang, Zhenyu; Lin, Guang; Lu, Shuai; Wang, Shaobu

2015-01-01T23:59:59.000Z

300

Modelling and Formal Verification of Timing Aspects in Large PLC Programs  

E-Print Network [OSTI]

One of the main obstacle that prevents model checking from being widely used in industrial control systems is the complexity of building formal models out of PLC programs, especially when timing aspects need to be integrated. This paper brings an answer to this obstacle by proposing a methodology to model and verify timing aspects of PLC programs. Two approaches are proposed to allow the users to balance the trade-off between the complexity of the model, i.e. its number of states, and the set of specifications possible to be verified. A tool supporting the methodology which allows to produce models for different model checkers directly from PLC programs has been developed. Verification of timing aspects for real-life PLC programs are presented in this paper using NuSMV.

Fernandez Adiego, B; Blanco Vinuela, E; Tournier, J-C; Gonzalez Suarez, V M; Blech, J O

2014-01-01T23:59:59.000Z

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


301

New probabilistic modeling and simulation methods for complex time-dependent systems  

SciTech Connect (OSTI)

This paper is a tutorial that presents a new method of modeling the probabilistic description of failure mechanisms in complex, time-dependent systems. The method of modeling employs a state vector differential equation representation of cumulative failure probabilities derived from Markov models associated with certain generic fault trees, and the method automatically includes common cause/common mode statistical dependencies, as well as time-related dependencies not considered in the literature previously. Simulations of these models employ a population dynamics representation of a probability space involving probability particle transitions among the Markov disjoint states. The particle transitions are governed by a random, Monte Carlo selection process.

Bartholomew, R.J.

1985-01-01T23:59:59.000Z

302

3D Weak-Dispersion Reverse-Time Migration with a StereoModeling Method  

E-Print Network [OSTI]

The finite difference method has been widely used in seismic modeling and reverse time migration. However, it generally has two issues: large computational cost and numerical dispersion. Recently, a nearly-analytic discrete ...

Li, Jingshuang

2013-01-01T23:59:59.000Z

303

A time-delay approach for the modeling and control of plasma instabilities in thermonuclear fusion  

E-Print Network [OSTI]

1 A time-delay approach for the modeling and control of plasma instabilities in thermonuclear for thermonuclear fusion plasmas. Indeed, advanced plasma confinement scenarios, such as the ones considered

Sipahi, Rifat

304

Power Series Introduction  

E-Print Network [OSTI]

Power Series 16.4 Introduction In this section we consider power series. These are examples of infinite series where each term contains a variable, x, raised to a positive integer power. We use the ratio test to obtain the radius of convergence R, of the power series and state the important result

Vickers, James

305

Mean time to meaningless: MTTDL, Markov models, and storage system reliability  

E-Print Network [OSTI]

Mean time to meaningless: MTTDL, Markov models, and storage system reliability Kevin M. Greenan Loss (MTTDL) has been the stan- dard reliability metric in storage systems for more than 20 years [3], the stan- dard metric of storage system reliability has been the Mean Time To Data Loss (MTTDL

Plank, Jim

306

USING TIME-LAPSE SEISMIC MEASUREMENTS TO IMPROVE FLOW MODELING OF CO2 INJECTION  

E-Print Network [OSTI]

Marly. The EOR process in the RCP section of the Weyburn Field uses CO2 and water injection to displaceUSING TIME-LAPSE SEISMIC MEASUREMENTS TO IMPROVE FLOW MODELING OF CO2 INJECTION IN THE WEYBURN, particularly CO2. Time lapse seismic monitoring has motivated changes to the reservoir description in a flow

307

Telescopic Time-Scale Bridging for Modeling Dispersion in Rapidly Oscillating Flows  

E-Print Network [OSTI]

Telescopic Time-Scale Bridging for Modeling Dispersion in Rapidly Oscillating Flows Ram K between the oscillation and dispersion time scales. Here, we present a methodology based on an implicit introduced errors. The error was found to decrease with mesh refinement, but a small inherent error

Zakhor, Avideh

308

Modeling and rendering heterogeneous fog in real-time using B-Spline wavelets  

E-Print Network [OSTI]

Modeling and rendering heterogeneous fog in real-time using B-Spline wavelets Anthony Giroud method to render heterogeneous fog in real-time. The extinction function of our fog, related to its to obtain a decomposition in both space and frequency domains. A grid traversal is used to render the fog

Paris-Sud XI, Université de

309

Using Space-Time Constraints to Guide Model Interoperability Paul F. Reynolds Jr.  

E-Print Network [OSTI]

to motion retargeting ­ accurately transferring human motions to animated characters. A typical goalUsing Space-Time Constraints to Guide Model Interoperability Paul F. Reynolds Jr. Dept of Computer-924-1039 (V) , 434-982-2214 (F) reynolds@virginia.edu Keywords: Interoperability, Multi-Resolution Modeling

Brogan, David

310

Expressing and computing passage time measures of GSPN models with HASL  

E-Print Network [OSTI]

Expressing and computing passage time measures of GSPN models with HASL Elvio Gilberto Amparore1 measures in (Tagged) GSPNs using the Hybrid Automata Stochastic Logic (HASL) and the statistical model), formally express them in HASL terms and assess them by means of simulation in the COSMOS tool. The interest

Paris-Sud XI, Université de

311

Time Step Sensitivity of Nonlinear Atmospheric Models: Numerical Convergence, Truncation Error Growth, and Ensemble Design  

E-Print Network [OSTI]

1973; Oran and Boris 1987; Murray 1989; Gershenfeld 1999). Weather and climate prediction models, which to the initial conditions, which is a major source of uncertainty in Numerical Weather Prediction (NWP; eTime Step Sensitivity of Nonlinear Atmospheric Models: Numerical Convergence, Truncation Error

Judd, Kevin

312

A Self-Assembly Model of Time-Dependent Glue Sudheer Sahu  

E-Print Network [OSTI]

A Self-Assembly Model of Time-Dependent Glue Strength Sudheer Sahu ¡ , Peng Yin ¡ , and John H,py,reif£ @cs.duke.edu Abstract. We propose a self-assembly model in which the glue strength between two and study cataly- sis and self-replication in the tile assembly. We then study the tile complexity

Reif, John H.

313

Real-time Rendering of Complex Vector Data on 3d Terrain Models  

E-Print Network [OSTI]

Real-time Rendering of Complex Vector Data on 3d Terrain Models M. Schneider, M. Guthe, and R of buildings, streets and runway (from left to right). Abstract. In this paper we present a hybrid technique model. The first part of this hybrid technique is a texture-based approach that is especially suited

Behnke, Sven

314

Harmonic Modelling of Thyristor Bridges using a Simplified Time Domain Method  

E-Print Network [OSTI]

1 Harmonic Modelling of Thyristor Bridges using a Simplified Time Domain Method P. W. Lehn, Senior form solution for the harmonic injection of the converter is developed. For the more general case model module takes as input the ac voltage harmonics at the point of common coupling and outputs

Lehn, Peter W.

315

Modeling FullEnvelope Aerodynamics of Small UAVs in RealTime Prof. Michael Selig  

E-Print Network [OSTI]

D M E S S Modeling FullEnvelope Aerodynamics of Small UAVs in RealTime Prof. Michael Selig Applied Aerodynamics Group and Subsonic Aerodynamics Research Lab Department of Aerospace Engineering will focus on the development of a full six degreeoffreedom aerodynamics modeling environment for small UAVs

Barthelat, Francois

316

Method for estimation of gravitational-wave transient model parameters in frequency-time maps  

E-Print Network [OSTI]

A common technique for detection of gravitational-wave signals is searching for excess power in frequency-time maps of gravitational-wave detector data. In the event of a detection, model selection and parameter estimation will be performed in order to explore the properties of the source. In this paper, we develop a Bayesian statistical method for extracting model-dependent parameters from observed gravitational-wave signals in frequency-time maps. We demonstrate the method by recovering the parameters of model gravitational-wave signals added to simulated advanced LIGO noise. We also characterize the performance of the method and discuss prospects for future work.

Michael Coughlin; Nelson Christensen; Jonathan Gair; Shivaraj Kandhasamy; Eric Thrane

2014-04-17T23:59:59.000Z

317

Improvements of the shock arrival times at the Earth model STOA  

E-Print Network [OSTI]

Prediction of the shocks' arrival times (SATs) at the Earth is very important for space weather forecast. There is a well-known SAT model, STOA, which is widely used in the space weather forecast. However, the shock transit time from STOA model usually has a relative large error compared to the real measurements. In addition, STOA tends to yield too much `yes' prediction, which causes a large number of false alarms. Therefore, in this work, we work on the modification of STOA model. First, we give a new method to calculate the shock transit time by modifying the way to use the solar wind speed in STOA model. Second, we develop new criteria for deciding whether the shock will arrive at the Earth with the help of the sunspot numbers and the angle distances of the flare events. It is shown that our work can improve the SATs prediction significantly, especially the prediction of flare events without shocks arriving at the Earth.

Liu, H -L

2015-01-01T23:59:59.000Z

318

Method for determination of .sup.18 O/.sup.16 O and .sup.2 H/.sup.1 H ratios and .sup.3 H (tritium) concentrations of xylem waters and subsurface waters using time series sampling  

DOE Patents [OSTI]

A method for determination of .sup.18 O/.sup.16 O and .sup.2 H/.sup.1 H ratios and .sup.3 H concentrations of xylem and subsurface waters using time series sampling, insulating sampling chambers, and combined .sup.18 O/.sup.16 O, .sup.2 H/.sup.1 H and .sup.3 H concentration data on transpired water. The method involves collecting water samples transpired from living plants and correcting the measured isotopic compositions of oxygen (.sup.18 O/.sup.16 O) and hydrogen (.sup.2 H/.sup.1 H and/or .sup.3 H concentrations) to account for evaporative isotopic fractionation in the leafy material of the plant.

Smith, Brian (1126 Delaware St., Berkeley, CA 94702); Menchaca, Leticia (1126 Delaware St., Berkeley, CA 94702)

1999-01-01T23:59:59.000Z

319

A Flow Time Model for Melt-Cast Insensitive Explosive Process Guillemin Jean-Philippe*, Brunet Luc  

E-Print Network [OSTI]

and inserted in our flow time equations. De Larrard's model for the calculation of the maximum packing density The purpose of this article is to propose a predictive model of the flow time necessary for emptying a reactor

Boyer, Edmond

320

Model Parameterization, Prior Distributions, and the General Time-Reversible Model in Bayesian Phylogenetics  

E-Print Network [OSTI]

Bayesian phylogenetic methods require the selection of prior probability distributions for all parameters of the model of evolution. These distributions allow one to incorporate prior information into a Bayesian analysis, ...

Zwickl, Derrick J.; Holder, Mark T.

2004-01-01T23:59:59.000Z

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


321

A crust and upper mantle model of Eurasia and North Africa for Pn travel time calculation  

SciTech Connect (OSTI)

We develop a Regional Seismic Travel Time (RSTT) model and methods to account for the first-order effect of the three-dimensional crust and upper mantle on travel times. The model parameterization is a global tessellation of nodes with a velocity profile at each node. Interpolation of the velocity profiles generates a 3-dimensional crust and laterally variable upper mantle velocity. The upper mantle velocity profile at each node is represented as a linear velocity gradient, which enables travel time computation in approximately 1 millisecond. This computational speed allows the model to be used in routine analyses in operational monitoring systems. We refine the model using a tomographic formulation that adjusts the average crustal velocity, mantle velocity at the Moho, and the mantle velocity gradient at each node. While the RSTT model is inherently global and our ultimate goal is to produce a model that provides accurate travel time predictions over the globe, our first RSTT tomography effort covers Eurasia and North Africa, where we have compiled a data set of approximately 600,000 Pn arrivals that provide path coverage over this vast area. Ten percent of the tomography data are randomly selected and set aside for testing purposes. Travel time residual variance for the validation data is reduced by 32%. Based on a geographically distributed set of validation events with epicenter accuracy of 5 km or better, epicenter error using 16 Pn arrivals is reduced by 46% from 17.3 km (ak135 model) to 9.3 km after tomography. Relative to the ak135 model, the median uncertainty ellipse area is reduced by 68% from 3070 km{sup 2} to 994 km{sup 2}, and the number of ellipses with area less than 1000 km{sup 2}, which is the area allowed for onsite inspection under the Comprehensive Nuclear Test Ban Treaty, is increased from 0% to 51%.

Myers, S; Begnaud, M; Ballard, S; Pasyanos, M; Phillips, W S; Ramirez, A; Antolik, M; Hutchenson, K; Dwyer, J; Rowe, C; Wagner, G

2009-03-19T23:59:59.000Z

322

2013-2014Series Engineering  

E-Print Network [OSTI]

.................................................................................... 4 EE 101 Creativity and Design in Electrical and Computer Engineering or CS 100 The Computer Science2013-2014Series College of Engineering University of Kentucky is accredited by the Southern of Kentucky. ComputerEngineering Computer engineering involves modeling, design, implementation, testing

Hayes, Jane E.

323

2012-2013 Series Engineering  

E-Print Network [OSTI]

.................................................................................... 4 EE 101 Creativity and Design in Electrical and Computer Engineering or CS 100 The Computer Science2012-2013 Series College of Engineering University of Kentucky is accredited by the Southern of Kentucky. ComputerEngineering Computer engineering involves modeling, design, implementation, testing

Hayes, Jane E.

324

2014-2015Series Engineering  

E-Print Network [OSTI]

................................................................................................... 4 EE 101 Creativity and Design in Electrical and Computer Engineering (fulfills the UK Core Arts2014-2015Series College of Engineering University of Kentucky is accredited by the Southern of Kentucky. ComputerEngineering Computer engineering involves modeling, design, implementation, testing

MacAdam, Keith

325

Accelerating dark energy models in bianchi Type-V space-time  

E-Print Network [OSTI]

Some new exact solutions of Einstein's field equations in a spatially homogeneous and anisotropic Bianchi type-V space-time with minimally interaction of perfect fluid and dark energy components have been obtained. To prevail the deterministic solution we choose the scale factor $a(t) = \\sqrt{t^{n}e^{t}}$, which yields a time dependent deceleration parameter (DP), representing a model which generates a transition of the universe from the early decelerating phase to the recent accelerating phase. We find that for $n \\geq 1$, the quintessence model is reproducible with present and expected future evolution of the universe. The other models (for $n models approach to isotropy at late time. For different values of $n$, we can generate a class of physically viable DE models. The cosmic jerk parameter in our descended model is also found to be in good concordance with the recent data of astrophysical observations under appropriate condition. The physical and geometric properties of spatially homogeneous and anisotropic cosmological models are discussed.

Anirudh Pradhan; H. Amirhashchi

2011-10-05T23:59:59.000Z

326

Observational constraints on models of the Universe with time variable Gravitational and Cosmological constants along MOG  

E-Print Network [OSTI]

The subject of this paper is to investigate the weak regime covariant scalar-tensor-vector gravity (STVG) theory, known as the MOdified gravity (MOG) theory of gravity. First, we show that the MOG in the absence of scalar fields is converted into $\\Lambda(t),G(t)$ models. Time evolution of the cosmological parameters for a family of viable models have been investigated. Numerical results with the cosmological data have been adjusted. We've introduced a model for dark energy (DE) density and cosmological constant which involves first order derivatives of Hubble parameter. To extend this model, correction terms including the gravitational constant are added. In our scenario, the cosmological constant is a function of time. To complete the model,interaction terms between dark energy and dark matter (DM) manually entered in phenomenological form. Instead of using the dust model for DM, we have proposed DM equivalent to a barotropic fluid. Time evolution of DM is a function of other cosmological parameters. Using sophisticated algorithms, the behavior of various quantities including the densities, Hubble parameter, etc. have been investigated graphically. The statefinder parameters have been used for the classification of DE models. Consistency of the numerical results with experimental data of $SneIa+BAO+CMB$ are studied by numerical analysis with high accuracy.

M. Khurshudyan; N. S. Mazhari; D. Momeni; R. Myrzakulov; M. Raza

2014-06-24T23:59:59.000Z

327

Time integration for diffuse interface models for two-phase flow  

SciTech Connect (OSTI)

We propose a variant of the ?-scheme for diffuse interface models for two-phase flow, together with three new linearization techniques for the surface tension. These involve either additional stabilizing force terms, or a fully implicit coupling of the Navier–Stokes and Cahn–Hilliard equation. In the common case that the equations for interface and flow are coupled explicitly, we find a time step restriction which is very different to other two-phase flow models and in particular is independent of the grid size. We also show that the proposed stabilization techniques can lift this time step restriction. Even more pronounced is the performance of the proposed fully implicit scheme which is stable for arbitrarily large time steps. We demonstrate in a Taylor-flow application that this superior coupling between flow and interface equation can decrease the computation time by several orders of magnitude.

Aland, Sebastian, E-mail: sebastian.aland@tu-dresden.de

2014-04-01T23:59:59.000Z

328

Signal extraction for nonstationary multivariate time series  

E-Print Network [OSTI]

-0.06-0.04-0.020.000.020.040.06 Total Core Figure 1: Core and Total PCE inflation, 1986 through 2010 information from Core inflation? · We use the Personal Consumption Expenditures (PCE) Core price index Trends (LLM): Total PCE Year 1990 1995 2000 2005 2010 -0.06-0.04-0.020.000.020.040.06 Total Trend CIs

Johnson, Raymond L.

329

Bootstrap Prediction Intervals for Time Series /  

E-Print Network [OSTI]

1.5 Joint Prediction intervals . . . . . . . . . . . . .1.6 Generalized Bootstrap prediction1.8.1 Bootstrap Prediction Intervals Based on Studentized

Pan, Li

2013-01-01T23:59:59.000Z

330

Overview of the Radiant Time Series Method  

E-Print Network [OSTI]

as basis for CLTDs and CLFs 1980 ­ ASHRAE publishes Cooling and Heating Load Calculation Manual by Rudoy) 1992 ­ ASHRAE publishes 2nd Edition of Cooling and Heating Load Calculation Manual by Mc publishes Cooling and Heating Load Calculation Principles with HBM and RTSM 2001 ­ HBM and RTSM

331

Time Series Evaluation of Portal Monitor Data  

SciTech Connect (OSTI)

Radiation portal monitors screen cargo and personal vehicle traffic at international border crossings to detect and interdict illicit sources which may be present in the commerce stream. One difficulty faced by RPM systems is the prospect of false alarms, or undesired alarms due to background fluctuation, or Naturally-Occurring Radioactive Material (NORM) sources in the commerce stream. In general, NORM alarms represent a significant fraction of the nuisance alarms at international border crossings, particularly with Polyvinyl-Toluene (PVT) RPM detectors, which have only very weak spectral differentiation capability. With PVT detectors, the majority of detected photon events fall within the Compton continuum of the material, allowing for very little spectral information to be preserved [1]. Previous work has shown that these detectors can be used for limited spectroscopy, utilizing around 8 spectral bins to further differentiate some NORM and other nuisance sources [2]. NaI based systems achieve much more detailed spectral resolution from each measurement of a source, but still combine all measurements over a vehicle's occupancy in order to arrive at a spectrum to be analyzed.

Robinson, Sean M.; Bender, Sarah E.; Lopresti, Charles A.; Woodring, Mitchell L.

2008-12-08T23:59:59.000Z

332

Introduction to Time Series Analysis Instructor  

E-Print Network [OSTI]

and Statistics 585 King Edward Av. Office 203D Phone: 562-5800 Ext. 3526 Email: rkulik@uottawa.ca Schedule

Kulik, Rafal

333

Time-Dependent Disk Models for the Microquasar GRS1915+105  

E-Print Network [OSTI]

We investigate different accretion disk models and viscosity prescriptions in order to provide a basic explanation for the exotic temporal behavior in GRS 1915+105. Based on the fact that the overall cycle times are very much longer than the rise/fall time scales in GRS 1915, we rule out the geometry of ADAF or a hot quasi-spherical region plus a cold outer disk for this source. We thus concentrate on geometrically thin Shakura-Sunyaev type disks (Shakura & Sunyaev 1973; hereafter SS73). We have devised a modified viscosity law that has a quasi-stable upper branch. Via numerical simulations, we show that the model does account for several gross observational features of GRS 1915+105. On the other hand, the rise/fall time scales are not short enough, and no rapid oscillations on time scales $\\simlt$ 10 s emerge naturally from the model. We then consider and numerically test a more elaborate model that includes the cold disk, a corona, and plasma ejections from the inner disk region and show that this model allows us to reproduce several additional observed features of GRS 1915+105. We conclude that the most likely structure of the accretion flow in this source is that of a cold disk with a modified viscosity prescription, plus a corona that accounts for much of the X-ray emission, and unsteady plasma ejections that occur when the luminosity of the source is high.

Sergei Nayakshin; Saul Rappaport; Fulvio Melia

1999-05-27T23:59:59.000Z

334

Incident detection using the Standard Normal Deviate model and travel time information from probe vehicles  

E-Print Network [OSTI]

INCIDENT DETECTION USING THE STANDARD iNORMAL DEVIATE MODEL AND TRAVEL TECHIE INFORMATION FROM PROBE VEHICLES A Thesis by CHRISTOPHER EUGENE MOUNTAIN Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment... of the requirement for the degree of MASTFR OF SCIENCE December 1993 Major Subject: Civil Engineering INCIDENT DETECTION USING THE STANDARD NORMAL DEVIATE MODEL AND TRAVEL TIME INFORMATION FROM PROBE VEHICLES A Thesis by CHRISTOPHER EUGENE MOUNTAIN Submitted...

Mountain, Christopher Eugene

2012-06-07T23:59:59.000Z

335

Real-time characterization of partially observed epidemics using surrogate models.  

SciTech Connect (OSTI)

We present a statistical method, predicated on the use of surrogate models, for the 'real-time' characterization of partially observed epidemics. Observations consist of counts of symptomatic patients, diagnosed with the disease, that may be available in the early epoch of an ongoing outbreak. Characterization, in this context, refers to estimation of epidemiological parameters that can be used to provide short-term forecasts of the ongoing epidemic, as well as to provide gross information on the dynamics of the etiologic agent in the affected population e.g., the time-dependent infection rate. The characterization problem is formulated as a Bayesian inverse problem, and epidemiological parameters are estimated as distributions using a Markov chain Monte Carlo (MCMC) method, thus quantifying the uncertainty in the estimates. In some cases, the inverse problem can be computationally expensive, primarily due to the epidemic simulator used inside the inversion algorithm. We present a method, based on replacing the epidemiological model with computationally inexpensive surrogates, that can reduce the computational time to minutes, without a significant loss of accuracy. The surrogates are created by projecting the output of an epidemiological model on a set of polynomial chaos bases; thereafter, computations involving the surrogate model reduce to evaluations of a polynomial. We find that the epidemic characterizations obtained with the surrogate models is very close to that obtained with the original model. We also find that the number of projections required to construct a surrogate model is O(10)-O(10{sup 2}) less than the number of samples required by the MCMC to construct a stationary posterior distribution; thus, depending upon the epidemiological models in question, it may be possible to omit the offline creation and caching of surrogate models, prior to their use in an inverse problem. The technique is demonstrated on synthetic data as well as observations from the 1918 influenza pandemic collected at Camp Custer, Michigan.

Safta, Cosmin; Ray, Jaideep; Lefantzi, Sophia; Crary, David (Applied Research Associates, Arlington, VA); Sargsyan, Khachik; Cheng, Karen (Applied Research Associates, Arlington, VA)

2011-09-01T23:59:59.000Z

336

Infrared problem for the Nelson model on static space-times  

E-Print Network [OSTI]

We consider the Nelson model with variable coefficients and investigate the problem of existence of a ground state and the removal of the ultraviolet cutoff. Nelson models with variable coefficients arise when one replaces in the usual Nelson model the flat Minkowski metric by a static metric, allowing also the boson mass to depend on position. A physical example is obtained by quantizing the Klein-Gordon equation on a static space-time coupled with a non-relativistic particle. We investigate the existence of a ground state of the Hamiltonian in the presence of the infrared problem, i.e. assuming that the boson mass tends to 0 at infinity.

Christian Gérard; Fumio Hiroshima; Annalisa Panati; Akito Suzuki

2011-01-03T23:59:59.000Z

337

A real-time hydrological model for flood prediction using GIS and the WWW  

E-Print Network [OSTI]

water distribution. The development of such a system would be particularly important outside of urban and spatial real-time, emergency decision support. Rather than discuss develop- ments in the modelling Computers, Environment and Urban Systems 27 (2003) 9­32 www.elsevier.com/locate/compenvurbsys 0198

Blackburn, Alan

338

Climate Projections Using Bayesian Model Averaging and Space-Time Dependence  

E-Print Network [OSTI]

Climate Projections Using Bayesian Model Averaging and Space-Time Dependence K. Sham Bhat, Murali Haran, Adam Terando, and Klaus Keller. Abstract Projections of future climatic changes are a key input to the design of climate change mitiga- tion and adaptation strategies. Current climate change projections

Haran, Murali

339

Accurate Modeling and Prediction of Energy Availability in Energy Harvesting Real-Time Embedded Systems  

E-Print Network [OSTI]

Binghamton University, State University of New York Binghamton, New York, USA {jlu5, sliu5, qwu, qqiuAccurate Modeling and Prediction of Energy Availability in Energy Harvesting Real-Time Embedded}@binghamton.edu Abstract -- Energy availability is the primary subject that drives the research innovations in energy

Qiu, Qinru

340

Discrete-Time Model of an IPMSM Based on Variational Integrators  

E-Print Network [OSTI]

as automobile traction drives for electric and hybrid electric vehicles. Since motor control is commonly. INTRODUCTION Interior permanent magnet synchronous motors (IPMSM) provide a high efficiency besides very high and thus motivate the need of exact discrete- time motor models. Furthermore, the electrical frequency

Paderborn, Universität

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


341

LINEAR TIME PERIODIC MODELLING OF POWER ELECTRONIC DEVICES FOR POWER SYSTEM HARMONIC ANALYSIS AND SIMULATION  

E-Print Network [OSTI]

LINEAR TIME PERIODIC MODELLING OF POWER ELECTRONIC DEVICES FOR POWER SYSTEM HARMONIC ANALYSIS by simulation. 1. INTRODUCTION The variety and the wide spread use of power electronic devices in the power networks is due to their diverse and multiple functions: compensation, protection and interface

Boyer, Edmond

342

Physiologically realistic modelling of a mechanism for neural representation of intervals of time  

E-Print Network [OSTI]

-8610, Japan c CREST, Japan Science and Technology (JST), Saitama 332-0012, Japan Abstract A model, Fuji Xerox Co. Ltd., 430 Sakai, Nakai-machi, Ashigarakami-gun, Kanagawa 259-0157, Japan b Department as well as the difference stated above, will lead us to the idea that an interval of time, T

Fukai, Tomoki

343

Modelling Planning and Scheduling Problems with Time and Resources* ROMAN BARTK  

E-Print Network [OSTI]

Modelling Planning and Scheduling Problems with Time and Resources* ROMAN BARTÁK Department of sequencing operators to achieve some goal. In STRIPS- like planning, the operator is defined by pre-conditions and effects, i.e., the pre-conditions must be satisfied to use the operator, and the effects hold after using

Bartak, Roman

344

A Novel Virtual Age Reliability Model for Time-to-Failure Prediction  

E-Print Network [OSTI]

counts, devices approaching physical feature size limits and nuclear plant comparable power densityA Novel Virtual Age Reliability Model for Time-to-Failure Prediction Yao Wang, Sorin Cotofana their relatively short operating lifetime. To overcome the MTTF weakness, this paper proposes a novel virtual age

Kuzmanov, Georgi

345

Compositionality in Real-Time Model Checking Jasper Berendsen and Frits Vaandrager  

E-Print Network [OSTI]

Compositionality in Real-Time Model Checking Jasper Berendsen and Frits Vaandrager Radboud Universiteit Nijmegen Laquso Lunch Colloquium, 8 november 2007 Jasper Berendsen and Vaandrager Compositionality Modules, etc, CCS, I/O automata, ACP, mCRL2, etc Lamport: "In reality there are only states" Jasper

Vaandrager, Frits

346

Long time asymptotics of solutions to the anharmonic oscillator model from nonlinear optics  

E-Print Network [OSTI]

from nonliear optics consist­ ing of Maxwell's equations @ t E = curl H \\Gamma @ t ~ P \\Gamma j; @ t HLong time asymptotics of solutions to the anharmonic oscillator model from nonlinear optics F optics, Maxwell's equations, exterior boundary­value­problem, asymptotic behaviour, AMS subject

Louisiana State University

347

Analysis of Competitive Electricity Markets under a New Model of Real-Time Retail Pricing with  

E-Print Network [OSTI]

Analysis of Competitive Electricity Markets under a New Model of Real-Time Retail Pricing with Ex for Information and Decision Systems, Massachusetts Institute of Technology, Cambridge, MA, USA {mardavij, mdrine loop system. Under this pricing mechanism, electricity is priced at the exant´e price (calculated based

Bhatia, Sangeeta

348

Mauve: a Component-based Modeling Framework for Real-time Analysis of Robotic Applications  

E-Print Network [OSTI]

Mauve: a Component-based Modeling Framework for Real-time Analysis of Robotic Applications Charles paradigm for robotic software devel- opment [2], applied in many applications [3], [4], [5], [6]. Resulting validation of the robotic application, by directly analysing the architecture specification, and limiting

349

Simulator Generation Using an Automaton Based Pipeline Model for Timing Analysis  

E-Print Network [OSTI]

Simulator Generation Using an Automaton Based Pipeline Model for Timing Analysis Rola Kassem, Mika the description of the pipeline. The description is transformed into an automaton and a set of resources which. The blocks communicate and synchronise with each other in order to handle the pipeline hazards. A pipeline

Paris-Sud XI, Université de

350

The Subcritical Collapse of Predator Populations in Discrete-Time Predator-Prey Models  

E-Print Network [OSTI]

The Subcritical Collapse of Predator Populations in Discrete-Time Predator-Prey Models MICHAEL G undergo a subcritical flip bifurcation with a concomitant crash in the predator's popula- tion. We review a technique for distinguishing between subcritical and supercritical flip bifurcations and provide examples

de Aguiar, Marcus A. M.

351

Three-dimensional finite difference time domain modeling of the Schumann resonance  

E-Print Network [OSTI]

Three-dimensional finite difference time domain modeling of the Schumann resonance parameters to as Schumann resonances and are excited by lightning discharges. The detection of such resonances on other frequency propagation is employed to study the Schumann resonance problems on Titan, Venus, and Mars

Pasko, Victor

352

MODELING SPACE-TIME DEPENDENT HELIUM BUBBLE EVOLUTION IN TUNGSTEN ARMOR UNDER IFE CONDITIONS  

E-Print Network [OSTI]

MODELING SPACE-TIME DEPENDENT HELIUM BUBBLE EVOLUTION IN TUNGSTEN ARMOR UNDER IFE CONDITIONS Qiyang dependent Helium transport in finite geometries, including the simultaneous transient production of defects of Helium bubbles. I. INTRODUCTION Helium production and helium bubble evolution in neutron

Ghoniem, Nasr M.

353

Solar Models: current epoch and time dependences, neutrinos, and helioseismological properties  

E-Print Network [OSTI]

We calculate accurate solar models and report the detailed time dependences of important solar quantities. We use helioseismology to constrain the luminosity evolution of the sun and report the discovery of semi-convection in evolved solar models that include diffusion. In addition, we compare the computed sound speeds with the results of p-mode observations by BiSON, GOLF, GONG, LOWL, and MDI instruments. We contrast the neutrino predictions from a set of eight standard-like solar models and four deviant (or deficient) solar models with the results of solar neutrino experiments. For solar neutrino and for helioseismological applications, we present present-epoch numerical tabulations of characteristics of the standard solar model as a function of solar radius, including the principal physical and composition variables, sound speeds, neutrino fluxes, and functions needed for calculating solar neutrino oscillations.

John N. Bahcall; M. H. Pinsonneault; Sarbani Basu

2001-03-13T23:59:59.000Z

354

Discrete-Time Block Models for Transmission Line Channels: Static and Doubly Selective Cases  

E-Print Network [OSTI]

Most methodologies for modeling Transmission Line (TL) based channels define the input-output relationship in the frequency domain (FD) and handle the TL resorting to a two-port network (2PN) formalism. These techniques have not yet been formally mapped into a discrete-time (DT) block model, which is useful to simulate and estimate the channel response as well as to design optimal precoding strategies. TL methods also fall short when they are applied to Time Varying (TV) systems, such as the power line channel. The objective of this paper is to establish if and how one can introduce a DT block model for the Power Line Channel. We prove that it is possible to use Lifting and Trailing Zeros (L&TZ) techniques to derive a DT block model that maps the TL-based input-output description directly in the time domain (TD) block channel model. More specifically, we find an interesting relationship between the elements of an ABCD matrix, defined in the FD, and filtering kernels that allow an elegant representation of...

Galli, Stefano

2011-01-01T23:59:59.000Z

355

Model-based image reconstruction from time-resolved diffusion data  

SciTech Connect (OSTI)

This paper addresses the issue of reconstructing the unknown field of absorption and scattering coefficients from time-resolved measurements of diffused light in a computationally efficient manner. The intended application is optical tomography, which has generated considerable interest in recent times. The inverse problem is posed in the Bayesian framework. The maximum {ital a posteriori} (MAP) estimate is used to compute the reconstruction. We use an edge- preserving generalized Gaussian Markov random field to model the unknown image. The diffusion model used for the measurements is solved forward in time using a finite-difference approach known as the alternating-directions implicit method. This method requires the inversion of a tridiagonal matrix at each time step and is therefore of O(N) complexity, where N is the dimensionality of the image. Adjoint differentiation is used to compute the sensitivity of the measurements with respect to the unknown image. The novelty of our method lies in the computation of the sensitivity since we can achieve it in O(N) time as opposed to O(N{sup 2}) time required by the perturbation approach. We present results using simulated data to show that the proposed method yields superior quality reconstructions with substantial savings in computation.

Saquib, S.S. [Purdue Univ., Lafayette, IN (United States); Hanson, K.M.; Cunningham, G.S. [Los Alamos National Lab., NM (United States)

1997-02-01T23:59:59.000Z

356

Real-Time Forcast Model Analysis of Daily Average Building Load for a Thermal Storage System Control  

E-Print Network [OSTI]

of a building and three real-time building load forecasting models were developed. They are first-order autogressive model, random walk model and linear regression model. Finally, the comparison of results show the random walk model provides the best...

Song, L.; Joo, I. S.; Guwana, S.

357

Series Transmission Line Transformer  

DOE Patents [OSTI]

A series transmission line transformer is set forth which includes two or more of impedance matched sets of at least two transmissions lines such as shielded cables, connected in parallel at one end ans series at the other in a cascading fashion. The cables are wound about a magnetic core. The series transmission line transformer (STLT) which can provide for higher impedance ratios and bandwidths, which is scalable, and which is of simpler design and construction.

Buckles, Robert A. (Livermore, CA); Booth, Rex (Livermore, CA); Yen, Boris T. (El Cerrito, CA)

2004-06-29T23:59:59.000Z

358

A New Method For Robust High-Precision Time-Series Photometry From Well-Sampled Images: Application to Archival MMT/Megacam Observations of the Open Cluster M37  

E-Print Network [OSTI]

We introduce new methods for robust high-precision photometry from well-sampled images of a non-crowded field with a strongly varying point-spread function. For this work, we used archival imaging data of the open cluster M37 taken by MMT 6.5m telescope. We find that the archival light curves from the original image subtraction procedure exhibit many unusual outliers, and more than 20% of data get rejected by the simple filtering algorithm adopted by early analysis. In order to achieve better photometric precisions and also to utilize all available data, the entire imaging database was re-analyzed with our time-series photometry technique (Multi-aperture Indexing Photometry) and a set of sophisticated calibration procedures. The merit of this approach is as follows: we find an optimal aperture for each star with a maximum signal-to-noise ratio, and also treat peculiar situations where photometry returns misleading information with more optimal photometric index. We also adopt photometric de-trending based on ...

Chang, S -W; Hartman, J D

2015-01-01T23:59:59.000Z

359

Analytic solutions for seismic travel time and ray path geometry through simple velocity models.  

SciTech Connect (OSTI)

The geometry of ray paths through realistic Earth models can be extremely complex due to the vertical and lateral heterogeneity of the velocity distribution within the models. Calculation of high fidelity ray paths and travel times through these models generally involves sophisticated algorithms that require significant assumptions and approximations. To test such algorithms it is desirable to have available analytic solutions for the geometry and travel time of rays through simpler velocity distributions against which the more complex algorithms can be compared. Also, in situations where computational performance requirements prohibit implementation of full 3D algorithms, it may be necessary to accept the accuracy limitations of analytic solutions in order to compute solutions that satisfy those requirements. Analytic solutions are described for the geometry and travel time of infinite frequency rays through radially symmetric 1D Earth models characterized by an inner sphere where the velocity distribution is given by the function V (r) = A-Br{sup 2}, optionally surrounded by some number of spherical shells of constant velocity. The mathematical basis of the calculations is described, sample calculations are presented, and results are compared to the Taup Toolkit of Crotwell et al. (1999). These solutions are useful for evaluating the fidelity of sophisticated 3D travel time calculators and in situations where performance requirements preclude the use of more computationally intensive calculators. It should be noted that most of the solutions presented are only quasi-analytic. Exact, closed form equations are derived but computation of solutions to specific problems generally require application of numerical integration or root finding techniques, which, while approximations, can be calculated to very high accuracy. Tolerances are set in the numerical algorithms such that computed travel time accuracies are better than 1 microsecond.

Ballard, Sanford

2007-12-01T23:59:59.000Z

360

A Model for Non-Linear Quantum Evolution based on Time Displaced Entanglement  

E-Print Network [OSTI]

We discuss a model for non-linear quantum evolution based on the idea of time displaced entanglement, produced by taking one member of an entangled pair on a round trip at relativistic speeds, thus inducing a time-shift between the pair. We show that decoherence of the entangled pair is predicted. For non-maximal entanglement this then implies the ability to induce a non-unitary, non-linear quantum evolution. Although exhibiting unusual characteristics, we show that these evolutions cannot be dismissed on the basis of entropic or causal arguments.

T. C. Ralph

2006-10-12T23:59:59.000Z

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


361

Real-Time Systems, Special Issue on Control-theoretical Approaches to Real-Time Computing, 23(1/2): 85-126, 2002 Feedback Control Real-Time Scheduling: Framework, Modeling, and Algorithms*  

E-Print Network [OSTI]

(1/2): 85-126, 2002 Feedback Control Real-Time Scheduling: Framework, Modeling, and Algorithms* Chenyang Lu}@cs.virginia.edu gt9s@ee.virginia.edu Abstract This paper presents a Feedback Control real-time Scheduling (FCS. These admission-control-based algorithms represent the third major paradigm for real-time scheduling. However

Lu, Chenyang

362

Late time acceleration in a non-commutative model of modified cosmology  

E-Print Network [OSTI]

We investigate the effects of noncommutativity between the position-position, position-momentum and momentum-momentum of a phase space corresponding to a modified cosmological model. We show that the existence of such noncommutativity results in a Moyal Poisson algebra between the phase space variables in which the product law between the functions is of the kind of an $\\alpha$-deformed product. We then transform the variables in such a way that the Poisson brackets between the dynamical variables take the form of a usual Poisson bracket but this time with a noncommutative structure. For a power law expression for the function of the Ricci scalar with which the action of the gravity model is modified, the exact solutions in the commutative and noncommutative cases are presented and compared. In terms of these solutions we address the issue of the late time acceleration in cosmic evolution.

B. Malekolkalami; K. Atazadeh; B. Vakili

2014-11-25T23:59:59.000Z

363

Modeling and analysis of EWMA control schemes with time varying control limits  

E-Print Network [OSTI]

of EWMA schemes that afford the desired degree of protection against shifts that lead to a potential increase in scrap. Next, a stochastic model of the EWMA control scheme with supplementary runs rules is constructed. Mean absorption time for various... be reworked constitute scrap. Depending upon the product that is being manufactured, observations falling above the USL or below the LSL will constitute scrap. Without loss of generality, let an observation falling beyond the USL constitute scrap. Clearly...

Chandrasekaran, Sreenivasan

1991-01-01T23:59:59.000Z

364

Fast history matching of time-lapse seismic and production data for high resolution models  

E-Print Network [OSTI]

..............................................................33 2.20 Discretization elements in finite-differences and streamline simulation..........34 2.21 Faulted grid with permeability contrast along non-neighbor connections. A finite LBL construction is provided to examine the underlying flow field... water cut match for synthetic model.....................................................61 3.6 Flow domain decoupling provided by streamline-based sensitivities ..............62 3.7 Water cut performance before and after generalized travel time...

Jimenez, Eduardo Antonio

2008-10-10T23:59:59.000Z

365

Evaluating Macro-Modeling Systems: An Application to the Area Wide Model. Downloadable from http://www.federalreserve.gov/ events/cbw/mcadam mestre aug30.pdf. ECB Working Paper Series  

E-Print Network [OSTI]

This paper considers approaches to considering the validity of the overall structure of macro-econometric models – specifically, the Area Wide Model of the European Central Bank. By structure, we refer to the dynamic (business-cycle) and steady-state features that the model purports to capture. This leads to two types of tests. The first, drawing on the DSGE literature, is concerned with whether the model matches business-cycle (high-frequency) data characteristics. This is implemented by a Cholesky bootstrap whereby the steady state of the model is stochastically simulated using historically consistent covariances. The generated data is analysed for stylised-facts fitting and, similarly, using the model’s implied spectral characteristics, for congruence with the data in terms of persistence, periodicity and spectral fit. Moments matching, however, is only one aspect of overall model evaluation. Consequently, we move to tests that combine high-frequency aspects (short-horizon forecasts) with long-run features (such as the existence and identification of steady states and trends). Recursive forecasting tests form the second part. The forecasts attempt to measure the accuracy of model-based forecasts both simulated outof-sample and in an in-sample exercise. The out-of-sample exercise analyses the 1- to 8-step-ahead forecasting ability of the model. For this, the model is re-estimated each time on a subset of the original

Peter Mcadam; Ricardo Mestre

2003-01-01T23:59:59.000Z

366

Viscosity, relaxation time, and dynamics within a model asphalt of larger molecules  

SciTech Connect (OSTI)

The dynamics properties of a new “next generation” model asphalt system that represents SHRP AAA-1 asphalt using larger molecules than past models is studied using molecular simulation. The system contains 72 molecules distributed over 12 molecule types that range from nonpolar branched alkanes to polar resins and asphaltenes. Molecular weights range from 290 to 890 g/mol. All-atom molecular dynamics simulations conducted at six temperatures from 298.15 to 533.15 K provide a wealth of correlation data. The modified Kohlrausch-Williams-Watts equation was regressed to reorientation time correlation functions and extrapolated to calculate average rotational relaxation times for individual molecules. The rotational relaxation rate of molecules decreased significantly with increasing size and decreasing temperature. Translational self-diffusion coefficients followed an Arrhenius dependence. Similar activation energies of ?42 kJ/mol were found for all 12 molecules in the model system, while diffusion prefactors spanned an order of magnitude. Viscosities calculated directly at 533.15 K and estimated at lower temperatures using the Debye-Stokes-Einstein relationship were consistent with experimental data for asphalts. The product of diffusion coefficient and rotational relaxation time showed only small changes with temperature above 358.15 K, indicating rotation and translation that couple self-consistently with viscosity. At lower temperatures, rotation slowed more than diffusion.

Li, Derek D.; Greenfield, Michael L., E-mail: greenfield@egr.uri.edu [Department of Chemical Engineering, University of Rhode Island, Kingston, Rhode Island 02881 (United States)

2014-01-21T23:59:59.000Z

367

Precursory measure of interoccurrence time associated with large earthquakes in the Burridge-Knopoff model  

SciTech Connect (OSTI)

We studied the statistical properties of interoccurrence time i.e., time intervals between successive earthquakes in the two-dimensional (2D) Burridge-Knopoff (BK) model, and have found that these statistics can be classified into three types: the subcritical state, the critical state, and the supercritical state. The survivor function of interoccurrence time is well fitted by the Zipf-Mandelbrot type power law in the subcritical regime. However, the fitting accuracy of this distribution tends to be worse as the system changes from the subcritical state to the supercritical state. Because the critical phase of a fault system in nature changes from the subcritical state to the supercritical state prior to a forthcoming large earthquake, we suggest that the fitting accuracy of the survivor distribution can be another precursory measure associated with large earthquakes.

Hasumi, Tomohiro [Department of Applied Physics, Advanced School of Science and Engineering, Waseda University, Shinjuku-ku Tokyo 169-8555 (Japan)

2008-11-13T23:59:59.000Z

368

Demand Response-Enabled Model Predictive HVAC Load Control in Buildings using Real-Time Electricity Pricing.  

E-Print Network [OSTI]

??A practical cost and energy efficient model predictive control (MPC) strategy is proposed for HVAC load control under dynamic real-time electricity pricing. The MPC strategy… (more)

Avci, Mesut

2013-01-01T23:59:59.000Z

369

Flow control techniques for real-time media applications in best-effort networks using fluid models  

E-Print Network [OSTI]

at the application layer. An end-to-end ?uid model is used, including the source bu?er, the network and the destination bu?er. Traditional con- trol techniques, along with more advanced adaptive predictive control methods, are considered in order to provide... OF THE END-TO-END FLOW TRANSPORT SYSTEM : : : : : : : : : : : : : : : : : : : : : : 25 A. Source Bu?er Model . . . . . . . . . . . . . . . . . . . . . 25 B. Network Dynamic Model . . . . . . . . . . . . . . . . . . . 27 1. Time-Varying Time Delay Model...

Konstantinou, Apostolos

2004-11-15T23:59:59.000Z

370

Test Cases for Wind Power Plant Dynamic Models on Real-Time Digital Simulator: Preprint  

SciTech Connect (OSTI)

The objective of this paper is to present test cases for wind turbine generator and wind power plant models commonly used during commissioning of wind power plants to ensure grid integration compatibility. In this paper, different types of wind power plant models based on the Western Electricity Coordinating Council Wind Generator Modeling Group's standardization efforts are implemented on a real-time digital simulator, and different test cases are used to gauge their grid integration capability. The low-voltage ride through and reactive power support capability and limitations of wind turbine generators under different grid conditions are explored. Several types of transient events (e.g., symmetrical and unsymmetrical faults, frequency dips) are included in the test cases. The differences in responses from different types of wind turbine are discussed in detail.

Singh, M.; Muljadi, E.; Gevorgian, V.

2012-06-01T23:59:59.000Z

371

A cyclic time-dependent Markov process to model daily patterns in wind turbine power production  

E-Print Network [OSTI]

Wind energy is becoming a top contributor to the renewable energy mix, which raises potential reliability issues for the grid due to the fluctuating nature of its source. To achieve adequate reserve commitment and to promote market participation, it is necessary to provide models that can capture daily patterns in wind power production. This paper presents a cyclic inhomogeneous Markov process, which is based on a three-dimensional state-space (wind power, speed and direction). Each time-dependent transition probability is expressed as a Bernstein polynomial. The model parameters are estimated by solving a constrained optimization problem: The objective function combines two maximum likelihood estimators, one to ensure that the Markov process long-term behavior reproduces the data accurately and another to capture daily fluctuations. A convex formulation for the overall optimization problem is presented and its applicability demonstrated through the analysis of a case-study. The proposed model is capable of r...

Scholz, Teresa; Estanqueiro, Ana

2013-01-01T23:59:59.000Z

372

Modeling the Phillips curve with unobserved components  

E-Print Network [OSTI]

Series Models and the Kalman Filter. Cambridge: Cambridge University Press. Harvey, A.C. and T.M.Trimbur (2003). General model-based ?lters for ex- tracting trends and cycles in economic time series. Review of Economics and Statistics, 85, 244-55. Harvey...

Harvey, Andrew C

373

Photon and neutrino spectra of time-dependent photospheric models of gamma-ray bursts  

SciTech Connect (OSTI)

Thermal photons from the photosphere may be the primary source of the observed prompt emission of gamma-ray bursts (GRBs). In order to produce the observed non-thermal spectra, some kind of dissipation mechanism near the photosphere is required. In this paper we numerically simulate the evolution of the photon spectrum in a relativistically expanding shell with a time-dependent numerical code. We consider two basic models. One is a leptonic model, where a dissipation mechanism heats the thermal electrons maintaining their high temperature. The other model involves a cascade process induced by pp(pn)-collisions which produce high-energy electrons, modify the thermal spectrum, and emit neutrinos. The qualitative properties of the photon spectra are mainly determined by the optical depth at which the dissipation mechanism sets in. Too large optical depths lead to a broad and curved spectrum contradicting the observations, while for optical depths smaller than unity the spectral hardness becomes softer than observed. A significant shift of the spectral peak energy to higher energies due to a large energy injection can lead to an overly broad spectral shape. We show ideal parameter ranges for which these models are able to reproduce the observed spectra. For the pn-collision model, the neutrino fluence in the 10–100 GeV range is well above the atmospheric neutrino fluence, but its detection is challenging for presently available detectors.

Asano, K. [Institute for Cosmic Ray Research, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8582 (Japan); Mészáros, P., E-mail: asanok@icrr.u-tokyo.ac.jp, E-mail: nnp@astro.psu.edu [Department of Astronomy and Astrophysics, Department of Physics, Center for Particle and Gravitational Astrophysics, Pennsylvania State University, University Park, PA 16802 (United States)

2013-09-01T23:59:59.000Z

374

On harmonic binomial series  

E-Print Network [OSTI]

We evaluate binomial series with harmonic number coefficients, providing recursion relations, integral representations, and several examples. The results are of interest to analytic number theory, the analysis of algorithms, and calculations of theoretical physics, as well as other applications.

Mark W. Coffey

2008-12-09T23:59:59.000Z

375

Time-Domain Absorbing Boundary Terminations for Waveguide Ports Based on State-Space Models  

E-Print Network [OSTI]

Absorbing boundary conditions for waveguide ports in time domain are important elements of transient approaches to treat RF structures. A successful way to implement these termination conditions is the decomposition of the transient fields in the absorbing plane in terms of modal field patterns. The absorbing condition is then accomplished by transferring the wave impedances (or admittances) of the modes to time domain, which leads to convolution operations involving Bessel functions and integrals of Bessel functions. This paper presents a new alternative approach: the convolution operations are approximated by appropriate state-space models whose system responses can be conveniently computed by standard integration schemes. These schemes are indispensable for transient simulations anyhow. Sufficiently far away from the cutoff frequency, a wideband match is achieved.

Flisgen, T; van Rienen, U

2014-01-01T23:59:59.000Z

376

TRANSIT TIMING OBSERVATIONS FROM KEPLER. V. TRANSIT TIMING VARIATION CANDIDATES IN THE FIRST SIXTEEN MONTHS FROM POLYNOMIAL MODELS  

SciTech Connect (OSTI)

Transit timing variations provide a powerful tool for confirming and characterizing transiting planets, as well as detecting non-transiting planets. We report the results of an updated transit timing variation (TTV) analysis for 1481 planet candidates based on transit times measured during the first sixteen months of Kepler observations. We present 39 strong TTV candidates based on long-term trends (2.8% of suitable data sets). We present another 136 weaker TTV candidates (9.8% of suitable data sets) based on the excess scatter of TTV measurements about a linear ephemeris. We anticipate that several of these planet candidates could be confirmed and perhaps characterized with more detailed TTV analyses using publicly available Kepler observations. For many others, Kepler has observed a long-term TTV trend, but an extended Kepler mission will be required to characterize the system via TTVs. We find that the occurrence rate of planet candidates that show TTVs is significantly increased ({approx}68%) for planet candidates transiting stars with multiple transiting planet candidates when compared to planet candidates transiting stars with a single transiting planet candidate.

Ford, Eric B. [Astronomy Department, University of Florida, 211 Bryant Space Sciences Center, Gainesville, FL 32111 (United States); Ragozzine, Darin; Holman, Matthew J. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Rowe, Jason F.; Barclay, Thomas; Borucki, William J.; Bryson, Stephen T.; Caldwell, Douglas A.; Kinemuchi, Karen; Koch, David G.; Lissauer, Jack J.; Still, Martin; Tenenbaum, Peter [NASA Ames Research Center, Moffett Field, CA 94035 (United States); Steffen, Jason H. [Fermilab Center for Particle Astrophysics, P.O. Box 500, MS 127, Batavia, IL 60510 (United States); Batalha, Natalie M. [Department of Physics and Astronomy, San Jose State University, San Jose, CA 95192 (United States); Fabrycky, Daniel C. [UCO/Lick Observatory, University of California, Santa Cruz, CA 95064 (United States); Gautier, Thomas N. [Jet Propulsion Laboratory/California Institute of Technology, Pasadena, CA 91109 (United States); Ibrahim, Khadeejah A.; Uddin, Kamal [Orbital Sciences Corporation/NASA Ames Research Center, Moffett Field, CA 94035 (United States); Kjeldsen, Hans, E-mail: eford@astro.ufl.edu [Department of Physics and Astronomy, Aarhus University, DK-8000 Aarhus C (Denmark); and others

2012-09-10T23:59:59.000Z

377

A Self-assembly Model of Time-Dependent Glue Sudheer Sahu, Peng Yin, and John H. Reif  

E-Print Network [OSTI]

A Self-assembly Model of Time-Dependent Glue Strength Sudheer Sahu, Peng Yin, and John H. Reif Abstract Self-assembly is a ubiquitous process in which small objects self- organize into larger model for theoretical studies of self-assembly. We propose a refined self-assembly model in which

Reif, John H.

378

Multi-fluid transport code modeling of time-dependent recycling in ELMy H-mode  

SciTech Connect (OSTI)

Simulations of a high-confinement-mode (H-mode) tokamak discharge with infrequent giant type-I ELMs are performed by the multi-fluid, multi-species, two-dimensional transport code UEDGE-MB, which incorporates the Macro-Blob approach for intermittent non-diffusive transport due to filamentary coherent structures observed during the Edge Localized Modes (ELMs) and simple time-dependent multi-parametric models for cross-field plasma transport coefficients and working gas inventory in material surfaces. Temporal evolutions of pedestal plasma profiles, divertor recycling, and wall inventory in a sequence of ELMs are studied and compared to the experimental time-dependent data. Short- and long-time-scale variations of the pedestal and divertor plasmas where the ELM is described as a sequence of macro-blobs are discussed. It is shown that the ELM recovery includes the phase of relatively dense and cold post-ELM divertor plasma evolving on a several ms scale, which is set by the transport properties of H-mode barrier. The global gas balance in the discharge is also analyzed. The calculated rates of working gas deposition during each ELM and wall outgassing between ELMs are compared to the ELM particle losses from the pedestal and neutral-beam-injection fueling rate, correspondingly. A sensitivity study of the pedestal and divertor plasmas to model assumptions for gas deposition and release on material surfaces is presented. The performed simulations show that the dynamics of pedestal particle inventory is dominated by the transient intense gas deposition into the wall during each ELM followed by continuous gas release between ELMs at roughly a constant rate.

Pigarov, A. Yu.; Krasheninnikov, S. I.; Hollmann, E. M. [University of California at San Diego, La Jolla, California 92093 (United States); Rognlien, T. D.; Lasnier, C. J. [Lawrence Livermore National Laboratory, Livermore, California 94551 (United States); Unterberg, E. [Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)

2014-06-15T23:59:59.000Z

379

Multi-fluid transport code modeling of time-dependent recycling in ELMy H-mode  

SciTech Connect (OSTI)

Simulations of a high-confinement-mode (H-mode) tokamak discharge with infrequent giant type-I ELMs are performed by the multi-fluid, multi-species, two-dimensional transport code UEDGE-MB, which incorporates the Macro-Blob approach for intermittent non-diffusive transport due to filamentary coherent structures observed during the Edge Localized Modes (ELMs) and simple time-dependent multi-parametric models for cross-field plasma transport coefficients and working gas inventory in material surfaces. Temporal evolutions of pedestal plasma profiles, divertor recycling, and wall inventory in a sequence of ELMs are studied and compared to the experimental time-dependent data. Short- and long-time-scale variations of the pedestal and divertor plasmas where the ELM is described as a sequence of macro-blobs are discussed. It is shown that the ELM recovery includes the phase of relatively dense and cold post-ELM divertor plasma evolving on a several ms scale, which is set by the transport properties of H-mode barrier. The global gas balance in the discharge is also analyzed. The calculated rates of working gas deposition during each ELM and wall outgassing between ELMs are compared to the ELM particle losses from the pedestal and neutral-beam-injection fueling rate, correspondingly. A sensitivity study of the pedestal and divertor plasmas to model assumptions for gas deposition and release on material surfaces is presented. The performed simulations show that the dynamics of pedestal particle inventory is dominated by the transient intense gas deposition into the wall during each ELM followed by continuous gas release between ELMs at roughly a constant rate.

Pigarov, A. Yu. [University of California, San Diego; Krasheninnikov, S. I. [University of California, La Jolla; Rognlien, T. D. [Lawrence Livermore National Laboratory (LLNL); Hollmann, E. M. [University of California, San Diego; Lasnier, C. J. [Lawrence Livermore National Laboratory (LLNL); Unterberg, Ezekial A [ORNL

2014-01-01T23:59:59.000Z

380

Waiting time distribution of solar energetic particle events modeled with a non-stationary Poisson process  

E-Print Network [OSTI]

We present a study of the waiting time distributions (WTDs) of solar energetic particle (SEP) events observed with the spacecraft $WIND$ and $GOES$. Both the WTDs of solar electron events (SEEs) and solar proton events (SPEs) display a power-law tail $\\sim \\Delta t^{-\\gamma}$. The SEEs display a broken power-law WTD. The power-law index is $\\gamma_{1} =$ 0.99 for the short waiting times ($$100 hours). The break of the WTD of SEEs is probably due to the modulation of the corotating interaction regions (CIRs). The power-law index $\\gamma \\sim$ 1.82 is derived for the WTD of SPEs that is consistent with the WTD of type II radio bursts, indicating a close relationship between the shock wave and the production of energetic protons. The WTDs of SEP events can be modeled with a non-stationary Poisson process which was proposed to understand the waiting time statistics of solar flares (Wheatland 2000; Aschwanden $\\&$ McTiernan 2010). We generalize the method and find that, if the SEP event rate $\\lambda = 1/\\Delt...

Li, Chuan; Wang, Linghua; Su, Wei; Fang, Cheng

2014-01-01T23:59:59.000Z

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


381

Modeling reaction quench times in the waste heat boiler of a Claus plant  

SciTech Connect (OSTI)

At the high temperatures found in the modified Claus reaction furnace, the thermal decomposition and oxidation of H[sub 2]S yields large quantities of desirable products, gaseous hydrogen (H[sub 2]) and sulfur (S[sub 2]). However, as the temperature of the gas stream is lowered in the waste heat boiler (WHB) located downstream of the furnace, the reverse reaction occurs leading to reassociation of H[sub 2] and S[sub 2] molecules. To examine the reaction quenching capabilities of the WHB, a rigorous computer model was developed incorporating recently published intrinsic kinetic data. A sensitivity study performed with the model demonstrated that WHBs have a wide range of operation with gas mass flux in the tubes from 4 to 24 kg/(m[sup 2] [center dot] s). Most important, the model showed that is was possible to operate WHBs such that quench times could be decreased to 40 ms, which is a reduction by 60% compared to a base case scenario. Furthermore, hydrogen production could be increased by over 20% simply by reconfiguring the WHB tubes.

Nasato, L.V.; Karan, K.; Mehrotra, A.K.; Behie, L.A. (Univ. of Calgary, Alberta (Canada). Dept. of Chemical and Petroleum Engineering)

1994-01-01T23:59:59.000Z

382

Development of an Optimum Tracer Set for Apportioning Emissions of Individual Power Plants Using Highly Time-Resolved Measurements and Advanced Receptor Modeling  

SciTech Connect (OSTI)

In previous studies, 11 elements (Al, As, Cd, Cr, Cu, Fe, Mn, Ni, Pb, Se, and Zn) were determined in 30-minute aerosol samples collected with the University of Maryland Semicontinuous Elements in Aerosol Sampler (SEAS; Kidwell and Ondov, 2001, 2004; SEAS-II) in several locations in which air quality is influenced by emissions from coal- or oil-fired power plants. At this time resolution, plumes from stationary high temperature combustion sources are readily detected as large excursions in ambient concentrations of elements emitted by these sources (Pancras et al. ). Moreover, the time-series data contain intrinsic information on the lateral diffusion of the plume (e.g., {sigma}{sub y}), which Park et al. (2005 and 2006) have exploited in their Pseudo-Deterministic Receptor Model (PDRM), to calculate emission rates of SO{sub 2} and 11 elements (mentioned above) from four individual coal- and oil-fired power plants in the Tampa Bay area. In the current project, we proposed that the resolving power of source apportionment methods might be improved by expanding the set of maker species and that there exist some optimum set of marker species that could be used. The ultimate goal was to determine the utility of using additional elements to better identify and isolate contributions of individual power plants to ambient levels of PM and its constituents. And, having achieved better resolution, achieve, also, better emission rate estimates. In this study, we optimized sample preparation and instrumental protocols for simultaneous analysis of 28 elements in dilute slurry samples collected with the SEAS with a new state-of-the-art Thermo-Systems, Inc., X-series II, Inductively Coupled Plasma Mass Spectroscopy (ICP-MS), and reanalyzed the samples previously collected in Tampa during the modeling period studied by Park et al. (2005) in which emission rates from four coal- and oil-fired power plants affected air quality at the sampling site. In the original model, Park et al. (2005), included 6 sources. Herein, we reassessed the number of contributing sources in light of the new data. A comprehensive list of sources was prepared and both our Gaussian Plume model and PMF were used to identify and predict the relative strengths of source contributions at the receptor sites. Additionally, PDRM was modified to apply National Inventory Emissions, Toxic Release Inventory, and Chemical Mass Balance source profile data to further constrain solutions. Both the original Tampa data set (SO{sub 2} plus 11 elements) and the new expanded data set (SO{sub 2} plus 23 elements) were used to resolve the contributions of particle constituents and PM to sources using Positive Matrix Factorization (PMF) and PDRM.

John Ondov; Gregory Beachley

2007-07-05T23:59:59.000Z

383

A Framework for the Real-Time Walkthrough of Massive Models 1 A Framework for the Real-Time Walkthrough of Massive Models  

E-Print Network [OSTI]

techniques. We demonstrate the system on a model of a coal-fired power plant composed of more than 15 million such techniques. Choosing a 15-million-triangle model of a coal-fired electric power plant (Image 1) as our (Graphics data structures), I.3.7 ­ Three-Dimensional Graphics and Realism (Virtual reality), J.2 ­ Physical

North Carolina at Chapel Hill, University of

384

arXiv:nlin.CD/0607029v114Jul2006 APS/123-QED Modeling Time Series of Real Systems using Genetic Programming  

E-Print Network [OSTI]

Programming Dilip P. Ahalpara Institute for Plasma Research, Near Indira Bridge, Gandhinagar-382428, India

Fernandez, Thomas

385

7000 Series MODIFIED MICROLITERTM  

E-Print Network [OSTI]

. This syringe series is unique, as the sample is held in the stainless steel needle. The tungsten plunger wire resistance to plunger movement is felt. Use of pliers on the knurled hub nut may be required to achieve this tightness. The black PTFE-coated plunger sleeve makes it easy to read the exact volume. Two sizes of spacers

Kleinfeld, David

386

Energy Management Webinar Series  

Broader source: Energy.gov [DOE]

Boost your knowledge on how to implement an energy management system through this four-part webinar series from the Superior Energy Performance program. Each webinar introduces various elements of the ISO 50001 energy management standard—based on the Plan-Do-Check-Act approach—and the associated steps of DOE's eGuide for ISO 50001 software tool.

387

Global Health Seminar Series  

E-Print Network [OSTI]

Bay Area Global Health Seminar Series Moving beyond millennium targets in global health: The challenges of investing in health and universal health coverage Although targets can help to focus global health efforts, they can also detract attention from deeper underlying challenges in global health

Klein, Ophir

388

Global Health Seminar Series  

E-Print Network [OSTI]

Bay Area Global Health Seminar Series Monday, January 27, 2014 2:30pm ­ 4:00pm (Reception to follow at the Center for Health Policy and the Woods Institute for the Environment. He studies how economic, political, and natural environments affect population health in developing countries using a mix of experimental

Klein, Ophir

389

Beyond the pseudo-time-dependent approach: chemical models of dense core precursors  

E-Print Network [OSTI]

Context: Chemical models of dense cloud cores often utilize the so-called pseudo-time-dependent approximation, in which the physical conditions are held fixed and uniform as the chemistry occurs. In this approximation, the initial abundances chosen, which are totally atomic in nature except for molecular hydrogen, are artificial. A more detailed approach to the chemistry of dense cold cores should include the physical evolution during their early stages of formation. Aims: Our major goal is to investigate the initial synthesis of molecular ices and gas-phase molecules as cold molecular gas begins to form behind a shock in the diffuse interstellar medium. The abundances calculated as the conditions evolve can then be utilized as reasonable initial conditions for a theory of the chemistry of dense cores. Methods: Hydrodynamic shock-wave simulations of the early stages of cold core formation are used to determine the time-dependent physical conditions for a gas-grain chemical network. We follow the cold post-sho...

Hassel, G E; Bergin, E A

2010-01-01T23:59:59.000Z

390

Area-preserving maps models of gyro-averaged ${\\bf E} \\times {\\bf B}$ chaotic transport  

E-Print Network [OSTI]

Discrete maps have been extensively used to model 2-dimensional chaotic transport in plasmas and fluids. Here we focus on area-preserving maps describing finite Larmor radius (FLR) effects on ${\\bf E} \\times {\\bf B}$ chaotic transport in magnetized plasmas with zonal flows perturbed by electrostatic drift waves. FLR effects are included by gyro-averaging the Hamiltonians of the maps which, depending on the zonal flow profile, can have monotonic or non-monotonic frequencies. In the limit of zero Larmor radius, the monotonic frequency map reduces to the standard Chirikov-Taylor map, and, in the case of non-monotonic frequency, the map reduces to the standard nontwist map. We show that in both cases FLR leads to chaos suppression, changes in the stability of fixed points, and robustness of transport barriers. FLR effects are also responsible for changes in the phase space topology and zonal flow bifurcations. Dynamical systems methods based on recurrence time statistics are used to quantify the dependence on the Larmor radius of the threshold for the destruction of transport barriers.

J. D. da Fonseca; D. del-Castillo-Negrete; I. L. Caldas

2014-09-10T23:59:59.000Z

391

Dark Energy Model in Anisotropic Bianchi Type-III Space-Time with Variable EoS Parameter  

E-Print Network [OSTI]

A new dark energy model in anisotropic Bianchi type-III space-time with variable equation of state (EoS) parameter has been investigated in the present paper. To get the deterministic model, we consider that the expansion $\\theta$ in the model is proportional to the eigen value $\\sigma^{2}_{~2}$ of the shear tensor $\\sigma^{j}_~i$. The EoS parameter $\\omega$ is found to be time dependent and its existing range for this model is in good agreement with the recent observations of SNe Ia data (Knop et al. 2003) and SNe Ia data with CMBR anisotropy and galaxy clustering statistics (Tegmark et al. 2004). It has been suggested that the dark energy that explains the observed accelerating expansion of the universe may arise due to the contribution to the vacuum energy of the EoS in a time dependent background. Some physical aspects of dark energy model are also discussed.

Anirudh Pradhan; Hassan Amirhashchi

2010-10-12T23:59:59.000Z

392

Ecosystem Diagnosis and Treatment Planning Model as Applied to Supplementation : Model Description, User Guide, and Theoretical Documentation for the Model Introduced in the Summary Report Series on Supplementation in the Columbia Basin.  

SciTech Connect (OSTI)

This document describes the formulation and operation of a model designed to assist in planning supplementation projects. It also has application in examining a broader array of questions related to natural fish production and stock restoration. The model is referred to as the Ecosystem Diagnosis and Treatment (EDT) Model because of its utility in helping to diagnose and identify possible treatments to be applied to natural production problems for salmonids. It was developed through the Regional Assessment of Supplementation Project (RASP), which was an initiative to help coordinate supplementation planning in the Columbia Basin. The model is operated within the spreadsheet environment of Quattro Pro using a system of customized menus. No experience with spreadsheet macros is required to operate it. As currently configured, the model should only be applied to spring chinook; modifications are required to apply it to fall chinook and other species. The purpose of the model is to enable managers to consider possible outcomes of supplementation under different sets of assumptions about the natural production system and the integration of supplementation fish into that system. It was designed to help assess uncertainty and the relative risks and benefits of alternative supplementation strategies. The model is a tool to facilitate both planning and learning; it is not a predictive model. This document consists of three principal parts. Part I provides a description of the model. Part II is a guide to running the model. Part III provides theoretical documentation. In addition, a sensitivity analysis of many of the model's parameters is provided in the appendix. This analysis was used to test whether the model produces consistent and reasonable results and to assess the relative effects of specific parameter inputs on outcome.

Lestelle, Lawrence C.; Lichatowich, James A.; Mobrand, Lars E.; Cullinan, Valerie I.

1994-03-01T23:59:59.000Z

393

IBM Lecture Series on Service Quality May 19, 2010  

E-Print Network [OSTI]

IBM Lecture Series on Service Quality May 19, 2010 Two New Perspectives for Service System Design at design time or run time, whether it is coarse-grained or fine-grained, and whether it is partial or total

Glushko, Robert J.

394

Time-dependent extinction rate and species abundance in a tangled-nature model of biological evolution  

E-Print Network [OSTI]

Time-dependent extinction rate and species abundance in a tangled-nature model of biological properties. The macrodynamics exhibit intermittent two-mode switching with a gradually decreasing extinction sense. The form of the species abundance curve compares well with observed func- tional forms. The model

Christensen, Kim

395

Large-Signal HBT Model with Improved Collector Transit Time Formulation for GaAs and InP Technologies  

E-Print Network [OSTI]

mi': iaE Large-Signal HBT Model with Improved Collector Transit Time Formulation for GaAs and In large-signal HBT model which accurately accounts for the intricate hias dependence of collector delay collector delay function accounts for the variation of electron velocity with electric field

Asbeck, Peter M.

396

Real-Time Track Prediction of Tropical Cyclones over the North Indian Ocean Using the ARW Model  

E-Print Network [OSTI]

Real-Time Track Prediction of Tropical Cyclones over the North Indian Ocean Using the ARW Model of Technology Bhubaneswar, Odisha, India A. ROUTRAY National Centre for Medium Range Weather Forecasting, Noida The performance of the Advanced Research version of the Weather Research and Forecasting (ARW) model in real

397

Functional Power Series  

E-Print Network [OSTI]

This work introduces a new functional series for expanding an analytic function in terms of an arbitrary analytic function. It is generally applicable and straightforward to use. It is also suitable for approximating the behavior of a function with a few terms. A new expression is presented for the composite function's n'th derivative. The inverse-composite method is handled in this work also.

Henrik Stenlund

2012-04-24T23:59:59.000Z

398

-DOE SciDAC 2005 meeting, Journal of Physics: Conference Series 16, 305-309 (2005) -Microbial Cell Modeling via Reacting Diffusive  

E-Print Network [OSTI]

Cell Modeling via Reacting Diffusive Particles Steven J. Plimpton and Alex Slepoy Sandia National-based simulator called ChemCell that we are developing with the goal of modeling the protein chemistry are represented by triangulated surfaces. Diffusing particles represent proteins, complexes, or other biomolecules

Plimpton, Steve

2005-01-01T23:59:59.000Z

399

CityFIT Urban Guide: Modelling and Deploying indicators of Property Exposure to Flooding in Lagos using LIDAR DEM and DSM data   

E-Print Network [OSTI]

application was prototyped for disseminating time-series flood model information and for reporting details of flood events as they occur to serve for model calibration and enhancement, thereby completing the flood modelling lifecycle....

Mosuro, Sulaiman

2012-11-29T23:59:59.000Z

400

Time-dependent Radiation Transfer in the Internal Shock Model Scenario for Blazar Jets  

E-Print Network [OSTI]

We describe the time-dependent radiation transfer in blazar jets, within the internal shock model. We assume that the central engine, which consists of a black hole and an accretion disk, spews out relativistic shells of plasma with different velocity, mass, and energy. We consider a single inelastic collision between a faster (inner) and a slower (outer) moving shell. We study the dynamics of the collision and evaluate the subsequent emission of radiation via the synchrotron and synchrotron self Compton (SSC) processes after the interaction between the two shells has begun. The collision results in the formation of a forward shock (FS) and a reverse shock (RS) that convert the ordered bulk kinetic energy of the shells into magnetic field energy and accelerate the particles, which then radiate. We assume a cylindrical geometry for the emission region of the jet. We treat the self-consistent radiative transfer by taking into account the inhomogeneity in the photon density throughout the region. In this paper, we focus on understanding the effects of varying relevant input parameters on the simulated spectral energy distribution (SED) and spectral variability patterns.

Manasvita Joshi; Markus Boettcher

2010-11-13T23:59:59.000Z

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


401

Fundamental Frequency Equivalenting Of Series Capacitors  

E-Print Network [OSTI]

series compensated line with Series Capacitors (SCs) and their Metal-Oxide Varistors (MOVs) installed in

With Movs In

402

Comment on "Time Step Sensitivity of Nonlinear Atmospheric Models: Numerical Convergence, Truncation Error Growth, and Ensemble Design" Teixeira et al. (2007)  

E-Print Network [OSTI]

Comment on "Time Step Sensitivity of Nonlinear Atmospheric Models: Numerical Convergence, Truncation Error Growth, and Ensemble Design" Teixeira et al.

Lun-Shin Yao; Dan Hughes

2007-04-26T23:59:59.000Z

403

Resource characterization series (final)  

SciTech Connect (OSTI)

Coals from the Princess Reserve District in northeastern Kentucky were obtained from the R-series cores and from Kentucky Geological Survey collections. The coals span the stratigraphic section from the Bruin coal near the base of the Breathitt Formation to a coal near the top of the Conemaugh Formation. The Princess District coals are high volatile C and B bituminous. High volatile A bituminous coals occur in southern Lawrence County. Reflectance highs and reactive maceral lows were noted in the Princess 3 and Princess 7 coals in along a north-south trend which may be parallel to the Waverly Arch.

Hower, J.C.; Wild, G.D.

1981-01-01T23:59:59.000Z

404

To appear in Biosystem 1998 TOWARDS A NEURAL MODEL OF TIMING  

E-Print Network [OSTI]

that maintains self-sustained (short-term memory) activity for a random time. The unit in the second layer

Bugmann, Guido

405

Lattice and off-lattice side chain models of protein folding: Linear time structure prediction better than 86% of optimal  

SciTech Connect (OSTI)

This paper considers the protein structure prediction problem for lattice and off-lattice protein folding models that explicitly represent side chains. Lattice models of proteins have proven extremely useful tools for reasoning about protein folding in unrestricted continuous space through analogy. This paper provides the first illustration of how rigorous algorithmic analyses of lattice models can lead to rigorous algorithmic analyses of off-lattice models. The authors consider two side chain models: a lattice model that generalizes the HP model (Dill 85) to explicitly represent side chains on the cubic lattice, and a new off-lattice model, the HP Tangent Spheres Side Chain model (HP-TSSC), that generalizes this model further by representing the backbone and side chains of proteins with tangent spheres. They describe algorithms for both of these models with mathematically guaranteed error bounds. In particular, the authors describe a linear time performance guaranteed approximation algorithm for the HP side chain model that constructs conformations whose energy is better than 865 of optimal in a face centered cubic lattice, and they demonstrate how this provides a 70% performance guarantee for the HP-TSSC model. This is the first algorithm in the literature for off-lattice protein structure prediction that has a rigorous performance guarantee. The analysis of the HP-TSSC model builds off of the work of Dancik and Hannenhalli who have developed a 16/30 approximation algorithm for the HP model on the hexagonal close packed lattice. Further, the analysis provides a mathematical methodology for transferring performance guarantees on lattices to off-lattice models. These results partially answer the open question of Karplus et al. concerning the complexity of protein folding models that include side chains.

Hart, W.E.; Istrail, S. [Sandia National Labs., Albuquerque, NM (United States). Algorithms and Discrete Mathematics Dept.

1996-08-09T23:59:59.000Z

406

VPL-E Series Data Projectors  

E-Print Network [OSTI]

lter Eco-friendly,GoodTCO,and Easy Operation The VPL-E Series is an Excellent Choice for Education consumption, allowing users to make significant savings on their electricity expenses. Simple Projector in education or business. The values are approximate. VPL-EX120 Conventional Model 6000 hours Longer Lamp

Saskatchewan, University of

407

Current theoretical models and future high resolution solar observations: preparing for ATST ASP Conference Series, Vol. 286, pp. 211 -226, 2003  

E-Print Network [OSTI]

of the umbra, FU, amounts to some 25% of that of the overall solar surface, F , while the penumbra of the umbra and decreases gradually outwards, reaches some 800 Gauss at the outer continuum = 211 #12;212 Schlichenmaier p-g . A model that incorporates three stratifications (the umbra, the penum

Schlichenmaier, Rolf

408

Validation of a model for faster than real time LMFBR core transient analysis  

SciTech Connect (OSTI)

This report briefly describes experimental validation of a computer model used to analyze LMFBR type core transients. This model is used to predict coolant, cladding, and fuel temperature distributions during transient overpower accidents. (JDH)

Tzanos, C.P.

1987-01-01T23:59:59.000Z

409

Numerical modeling of fluid flow and time-lapse seismics to monitor ...  

E-Print Network [OSTI]

May 30, 2014 ... and saturation. The model considers the geometrical features of the formations, .... mudstone layers inside the Utsira formation the complex bulk and shear ..... obtained from the flow simulator to build a 2D model of the Utsira.

santos

410

Hydrogeologic Modeling: GLY-5826 Meeting time: T, Th 11-12:15  

E-Print Network [OSTI]

11. Finite Element Methods a. MicroFEM b. SUTRA 12. Fractured Media 13. Analytic Element models Level: Graduate 5826 Sections: 1 Course Catalogue Description Techniques used in modeling groundwater introductions to the theory and implementation of hydrogeological modeling techniques. Students will develop

Sukop, Mike

411

CLEAR (Calculates Logical Evacuation And Response): A Generic Transportation Network Model for the Calculation of Evacuation Time Estimates  

SciTech Connect (OSTI)

This paper describes the methodology and application of the computer model CLEAR (Calculates Logical Evacuation And Response) which estimates the time required for a specific population density and distribution to evacuate an area using a specific transportation network. The CLEAR model simulates vehicle departure and movement on a transportation network according to the conditions and consequences of traffic flow. These include handling vehicles at intersecting road segments, calculating the velocity of travel on a road segment as a function of its vehicle density, and accounting for the delay of vehicles in traffic queues. The program also models the distribution of times required by individuals to prepare for an evacuation. In order to test its accuracy, the CLEAR model was used to estimate evacuatlon tlmes for the emergency planning zone surrounding the Beaver Valley Nuclear Power Plant. The Beaver Valley site was selected because evacuation time estimates had previously been prepared by the licensee, Duquesne Light, as well as by the Federal Emergency Management Agency and the Pennsylvania Emergency Management Agency. A lack of documentation prevented a detailed comparison of the estimates based on the CLEAR model and those obtained by Duquesne Light. However, the CLEAR model results compared favorably with the estimates prepared by the other two agencies.

Moeller, M. P.; Urbanik, II, T.; Desrosiers, A. E.

1982-03-01T23:59:59.000Z

412

Competing Models for the Timing of Cryogenian Glaciation: Evidence From the Kingston Peak Formation, Southeastern California  

E-Print Network [OSTI]

a fossil water table: Sedimentology, v. 14, p. 175-185, 6Neoproterozoic times: Sedimentology Review, v. 1, p. 1-16.1996, Stratigraphy, sedimentology, and isotopic geochemistry

Mrofka, David Douglas

2010-01-01T23:59:59.000Z

413

Gibbsianness versus Non-Gibbsianness of time-evolved planar rotor models  

E-Print Network [OSTI]

enough. Le Ny and Redig generalized in [LeNRed02] the result for small times t to more general dynamics

414

Discrete-Time Dataflow Models for Visual Simulation in Ptolemy II  

E-Print Network [OSTI]

in Ptolemy II is a timed extension of the Synchronous Dataflow (SDF) domain. Although not completely backward compatible with SDF, DT keeps most of the desirable properties of SDF like static scheduling, regular in Ptolemy II 3.2 Synchronous Dataflow (SDF) Domain 3.3 Discrete Event (DE) Domain 3.4 Continuous Time (CT

415

Model reduction of systems exhibiting two-time scale behavior or parametric uncertainty  

E-Print Network [OSTI]

exhibiting two-time scale behavior as well as parametric uncertainty has received little attention to date. This work addresses these types of problems in detail. Systems with two-time scale behavior can be described by differential-algebraic equations (DAEs...

Sun, Chuili

2007-04-25T23:59:59.000Z

416

Experiments with a time-dependent, zonally averaged, seasonal, enery balance climatic model  

E-Print Network [OSTI]

planetary albedo a~ insolation Q~ albedo constant b , mixing temperature T ~ and 0 0he consistency factor c 20 Presen zonal values of extraterrestrial -2 insolation for the middle of the month (Wm ). . . . . 23 Zonal values of planetary albedo... values of the fraction of ocean, f~ R from (22), model determined R, and the five sets of R4. 30 Nomenclature used for model experiment. ". . . 32 The difference between observed and experiment Cl(R1) mean annual temperatures, AT; the model...

Thompson, Starley Lee

2012-06-07T23:59:59.000Z

417

Sub-national TIMES model for analyzing regional future use of Biomass and Biofuels in France and  

E-Print Network [OSTI]

1 Sub-national TIMES model for analyzing regional future use of Biomass and Biofuels in France Introduction Renewable energy sources such as biomass and biofuels are increasingly being seen as important of biofuels on the final consumption of energy in transport should be 10%. The long-term target is to reduce

Boyer, Edmond

418

Peatland carbon cycle responses to hydrological change at time scales from years to centuries: Impacts on model  

E-Print Network [OSTI]

Peatland carbon cycle responses to hydrological change at time scales from years to centuries: Impacts on model simulations and regional carbon budgets By Benjamin N. Sulman A dissertation submitted to the long-term storage of carbon in peat, these ecosystems contain a significant fraction of the global

Wisconsin at Madison, University of

419

1028 IEEE TRANSACTIONS ON POWER ELECTRONICS, VOL. 14, NO. 6, NOVEMBER 1999 Discrete Time Modeling and Control of  

E-Print Network [OSTI]

S 0885-8993(99)08907-3. and high-power inverter applications. Consequently, improved dynamics1028 IEEE TRANSACTIONS ON POWER ELECTRONICS, VOL. 14, NO. 6, NOVEMBER 1999 Discrete Time Modeling Abstract--A new voltage source converter control approach is presented, based on multivariable z

Lehn, Peter W.

420

Metric spaces as models for real-time concurrency G.M. Reed and A.W. Roscoe1  

E-Print Network [OSTI]

Pro- cesses) We shall essentially extend the abstract syntax for untimed CSP from [BHR,BR] (with for real time concurrent systems, based on the fail- ures model for CSP. The fixed point theory is based. We have chosen to base our work on (extensions of) the theoretical version of CSP and to try

Roscoe, Bill

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


421

Modeling-Computer Simulations At Long Valley Caldera Geothermal...  

Open Energy Info (EERE)

and components of two continuous GPS time series. Additionally, the model explains the spatial extent of deformation observed by InSAR data covering the 1997-98 inflation...

422

A Four-Dimensional Viscoelastic Deformation Model For Long Valley...  

Open Energy Info (EERE)

and components of two continuous GPS time series. Additionally, the model explains the spatial extent of deformation observed by InSAR data covering the 1997-98 inflation...

423

Causal Modeling with Applications to the Foreign Exchange Market  

E-Print Network [OSTI]

A combination of time series models and causal search algorithms is applied to the foreign exchange markets to find causal linkages between the six most widely traded currencies (Australian dollar, Canadian dollar, euro, Great Britain pound sterling...

Deaton, Brian D.

2013-11-27T23:59:59.000Z

424

Ris DTU 09-06-08 Waste-to-energy technologies in TIMES models  

E-Print Network [OSTI]

(focusing on Denmark) Long tradition for waste incineration for district heating · How to model waste that supply base-load district heating. #12;Risø DTU 09-06-08 13 Modelling new Waste for Energy Technologies station for households and businesses. Some electricity is generated, but most energy is used for district

425

Nonlinearity and noise modeling of operational transconductance amplifiers for continuous time analog filters  

E-Print Network [OSTI]

A general framework for performance optimization of continuous-time OTA-C (Operational Transconductance Amplifier-Capacitor) filters is proposed. Efficient procedures for evaluating nonlinear distortion and noise valid for any filter of arbitrary...

Ramachandran, Arun

2006-08-16T23:59:59.000Z

426

Ris-R-1174(EN) RTMOD: Real-Time MODel Evaluation  

E-Print Network [OSTI]

to simulate the atmospheric dispersion of harmful materials, as radioactive pollutants. RTMOD is structured evaluation for the inter-comparison of real-time forecasts produced by long-range atmospheric dispersion

427

Modeling real-time human-automation collaborative scheduling of unmanned vehicles  

E-Print Network [OSTI]

Recent advances in autonomy have enabled a future vision of single operator control of multiple heterogeneous Unmanned Vehicles (UVs). Real-time scheduling for multiple UVs in uncertain environments will require the ...

Clare, Andrew S

2013-01-01T23:59:59.000Z

428

Flow Control of Real Time Multimedia Applications Using Model Predictive Control with a Feed Forward Term  

E-Print Network [OSTI]

. In this research, the flow accumulation is the signal used in feedback for flow control. It has the advantage of reflecting both packet losses and delays; therefore, it is a better choice. Using network simulations, the accumulations of real-time audio... based on ARX predictor and utilizes sending bit rate as input and accumulation as output signal. The control effort is to remain the accumulations of real-time multimedia flows at a certain reference. From network simulation results, he concluded...

Duong, Thien Chi

2011-02-22T23:59:59.000Z

429

On the rheological models used for time-domain methods of seismic wave propagation  

E-Print Network [OSTI]

January 2005. [1] After publications by Emmerich and Korn [1987] and Carcione et al. [1988a, 1988b rheological models ­ generalized Maxwell body (as defined by Emmerich and Korn) or generalized Zener body. Two

430

Model predictive control with application to real-time hardware and guided parafoil  

E-Print Network [OSTI]

Model Predictive Control (MPC) is a control strategy that is suitable for optimizing the performance of constrained systems. Constraints are present in all control systems due to the physical and environmental limits on ...

Alaniz, Abran, 1980-

2004-01-01T23:59:59.000Z

431

Fast History Matching of Time-Lapse Seismic and Production-Data for High Resolution Models  

E-Print Network [OSTI]

for the calibration of geologic spatial variability which ultimately contributes to the improvement of reservoir development and management strategies. Among the limited variety of techniques for the integration of dynamic seismic data into reservoir models...

Rey Amaya, Alvaro

2012-10-19T23:59:59.000Z

432

Real-time detection of malicious network activity using stochastic models  

E-Print Network [OSTI]

This dissertation develops approaches to rapidly detect malicious network traffic including packets sent by portscanners and network worms. The main hypothesis is that stochastic models capturing a host's particular ...

Jung, Jaeyeon, Ph. D. Massachusetts Institute of Technology

2006-01-01T23:59:59.000Z

433

Systematic time-based study for quantifying the uncertainty of uncalibrated models in building energy simulations  

E-Print Network [OSTI]

This thesis documents the usefulness and accuracy of uncalibrated simulations to determine for what end-uses these simulations should be used. The study was divided into three segments 1)comparison of the accuracy of two simulation models, massless...

Ahmad, Mushtaq

2005-07-27T23:59:59.000Z

434

Shortfall risk minimization in discrete time financial market models Noufel Frikha  

E-Print Network [OSTI]

. In a Markovian framework, we propose and analyze several algorithms based on Monte Carlo simulations to estimate by using a self-financing strategy on finite horizon time. The unique cost of replication is the expected which requires a large amount of initial capital. However, this approach is known to take into account

Paris-Sud XI, Université de

435

Structural Nested Mean Models for Assessing Time-Varying Causal Effect Moderation  

E-Print Network [OSTI]

= No Effect Outpatient substance abuse treatment is better than residential treatment for individuals of Suicide in Primary Care Elderly: CT) (a1, a2) Time-varying treatment pattern; at is binary (0,1) Y (a1, a21 Thomas R. Ten Have2 Susan A. Murphy3 1 Health Services Research in Primary Care, Durham VA MC 1

Murphy, Susan A.

436

Transit Timing Observations from Kepler: IV. Confirmation of 4 Multiple Planet Systems by Simple Physical Models  

SciTech Connect (OSTI)

Eighty planetary systems of two or more planets are known to orbit stars other than the Sun. For most, the data can be sufficiently explained by non-interacting Keplerian orbits, so the dynamical interactions of these systems have not been observed. Here we present 4 sets of lightcurves from the Kepler spacecraft, which each show multiple planets transiting the same star. Departure of the timing of these transits from strict periodicity indicates the planets are perturbing each other: the observed timing variations match the forcing frequency of the other planet. This confirms that these objects are in the same system. Next we limit their masses to the planetary regime by requiring the system remain stable for astronomical timescales. Finally, we report dynamical fits to the transit times, yielding possible values for the planets masses and eccentricities. As the timespan of timing data increases, dynamical fits may allow detailed constraints on the systems architectures, even in cases for which high-precision Doppler follow-up is impractical.

Fabrycky, Daniel C.; /UC, Santa Cruz; Ford, Eric B.; /Florida U.; Steffen, Jason H.; /Fermilab; Rowe, Jason F.; /SETI Inst., Mtn. View /NASA, Ames; Carter, Joshua A.; /Harvard-Smithsonian Ctr. Astrophys.; Moorhead, Althea V.; /Florida U.; Batalha, Natalie M.; /San Jose State U.; Borucki, William J.; /NASA, Ames; Bryson, Steve; /NASA, Ames; Buchhave, Lars A.; /Bohr Inst. /Copenhagen U.; Christiansen, Jessie L.; /SETI Inst., Mtn. View /NASA, Ames /Caltech

2012-01-01T23:59:59.000Z

437

Econometric Modelling of World Oil Supplies: Terminal Price and the Time to Depletion  

E-Print Network [OSTI]

This paper develops a novel approach by which to identify the price of oil at the time of depletion; the so-called terminal price of oil. It is shown that while the terminal price is independent of both GDP growth and the price elasticity of energy...

Mohaddes, Kamiar

2012-03-02T23:59:59.000Z

438

Discrete choice models of traveler participation in differential time of day pricing programs  

E-Print Network [OSTI]

variable pricing experiments, there is little empirical data on potential traveler response and traf Tolls that vary based on time of day or congestion are gaining attention around the world as a potential travel demand management strategy that can shift peak period travel to off peak periods thereby

Burris, Mark W.

439

OSPREY Model  

SciTech Connect (OSTI)

The absence of industrial scale nuclear fuel reprocessing in the U.S. has precluded the necessary driver for developing the advanced simulation capability now prevalent in so many other countries. Thus, it is essential to model complex series of unit operations to simulate, understand, and predict inherent transient behavior and feedback loops. A capability of accurately simulating the dynamic behavior of advanced fuel cycle separation processes will provide substantial cost savings and many technical benefits. The specific fuel cycle separation process discussed in this report is the off-gas treatment system. The off-gas separation consists of a series of scrubbers and adsorption beds to capture constituents of interest. Dynamic models are being developed to simulate each unit operation involved so each unit operation can be used as a stand-alone model and in series with multiple others. Currently, an adsorption model has been developed within Multi-physics Object Oriented Simulation Environment (MOOSE) developed at the Idaho National Laboratory (INL). Off-gas Separation and REcoverY (OSPREY) models the adsorption of off-gas constituents for dispersed plug flow in a packed bed under non-isothermal and non-isobaric conditions. Inputs to the model include gas, sorbent, and column properties, equilibrium and kinetic data, and inlet conditions. The simulation outputs component concentrations along the column length as a function of time from which breakthrough data is obtained. The breakthrough data can be used to determine bed capacity, which in turn can be used to size columns. It also outputs temperature along the column length as a function of time and pressure drop along the column length. Experimental data and parameters were input into the adsorption model to develop models specific for krypton adsorption. The same can be done for iodine, xenon, and tritium. The model will be validated with experimental breakthrough curves. Customers will be given access to OSPREY to used and evaluate the model.

Veronica J. Rutledge

2013-01-01T23:59:59.000Z

440

Land cover time profiles from linear mixture models applied to MODIS images P. Oliveira a,  

E-Print Network [OSTI]

the coarse spatial resolution of satellites such as the Advanced Very High Resolution Radiometer (AVHRR) (e and AQUA launched on December 18, 1999 and on May 4, 2002, respectively. MODIS images correspond to high the pixel. In linear models (LMM) the electromagnetic energy interacts with a single component before being

Gonçalves, Paulo

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


441

SPEECH MODELLING BY NON-STATIONARY PARTIALS WITH TIME VARYING AMPLITUDE AND FREQUENCY  

E-Print Network [OSTI]

in a speech enhancement system. Keywords: Speech Decomposition, Chirp Estimation 1. INTRODUCTION Recently performance in speech modeling and enhancement. Meth- ods like sinusoidal analysis [1] treat the speech heav- ily on the harmonic speech structure of the analyzed signal and when using in speech enhancement

Dony, Bob

442

A Time-AverageModel of the RF PlasmaSheath Demetre J, Economou.3  

E-Print Network [OSTI]

, University of Illinois, Urbana, Illinois 61801 David R. Evans* Tektronix Incorporated, Beaverton, Oregon 97077 Richard C. Alkire* Department of Chemical Engineering, University of Illinois, Urbana, Illinois 6t velocity. The sheath model was used to investigate the ion energy and flux on the electrodes of plasma

Economou, Demetre J.

443

Modelling the thermal quenching mechanism in quartz based on time-resolved optically stimulated luminescence  

E-Print Network [OSTI]

, Denmark c Nordic Laboratory for Luminescence Dating, Department of Earth Science, Aarhus University, Risø luminescence Pulsed OSL Thermoluminescence Quartz Luminescence lifetimes Kinetic rate equations Kinetic model temperature is raised, and has been observed in both thermo- luminescence (TL) and optically stimulated

Chen, Reuven

444

Right on time: Measuring Kuramoto model coupling from a survey of wristwatches  

E-Print Network [OSTI]

Using a survey of wristwatch synchronization from a randomly selected group of independent volunteers, one can model the system as a Kuramoto-type coupled oscillator network. Based on the phase data, both the order parameter and an estimated value of the coupling is derived and the possibilities for similar research to deduce topology from dynamics are discussed.

Reginald D. Smith

2010-03-25T23:59:59.000Z

445

Conceptually-Based Shot Noise Modelling of Streamflows at Short Time FEDERICO MURRONE, FABIO ROSSI  

E-Print Network [OSTI]

-year response lag, of aquifers which run dry by the end of the dry season and of subsurface runoff. The surface increases and slow recessions. These features prevent the use of ARMA-type of models [Box and Jenkins, 1976 acts as the input of a system that is representative of the transformations operated by the watershed

Poggi, Davide

446

Marcellus Shale Educational Webinar Series  

E-Print Network [OSTI]

#12;Marcellus Shale Litigation and Legislation December 17, 2009 7 . Pennsylvania Oil and Gas Law1 Marcellus Shale Educational Webinar Series October 2009 - March 2010 Penn State Cooperative Extension #12;2 Marcellus Shale Webinar Series Planning Committee · Members ­ Mark Douglass, Jefferson

Boyer, Elizabeth W.

447

Time-varying Linear Regression with Total Variation Regularization  

E-Print Network [OSTI]

a sparse set of parameters describing the energy consumption of a refrigerator and enables us to predict in the time series. Our motivating example is the problem of modeling and predicting energy consumption learn- ing the parameters of multiple linear systems as well as the change points that describe when

Murphy, Robert F.

448

Seminar Series Jill Herschleb  

E-Print Network [OSTI]

have characterized the fine-scale genomic structure of the model breast cancer cell line MCF-7. Over 1, Genetics/Biotechnology Center, 425 Henry Mall Fine-Scale Genomic Structure and Variation in the MCF-7 Breast Cancer Cell Line Abstract: Chromosomal abnormalities are found in all types of cancer

Payseur, Bret

449

TIME-LAPSE MODELING AND INVERSION OF CO2 SATURATION FOR SEQUESTRATION AND ENHANCED OIL RECOVERY  

SciTech Connect (OSTI)

In the fifth quarter of this DOE NETL project, they have implemented an algorithm that inverts for changes in fluid properties over time using time-lapse seismic anomalies. This algorithm constitutes the second step in the inversion procedure for Phase III of the project. They demonstrate this inversion procedure with a synthetic data example. Additional activities in this reporting period include a trip by the Principal investigator to an International Monitoring Workshop sponsored by the IEA Greenhouse Gas R and D Program in Santa Cruz, California. In the next quarter, they will further process the Sleipner data to prepare it for later inversion, and continue investigating alternative methods for calculating properties of oil/brine/CO{sub 2} systems.

Mark A. Meadows

2005-02-18T23:59:59.000Z

450

Time-domain Simulation of Multibody Floating Systems based on State-space Modeling Technology  

E-Print Network [OSTI]

of ship-to-ship cargo transfer using the spar.................... 13 1.4 Flowchart for the time-domain multibody simulation tool ........................ 16 2.1 A block diagram of a PID controller... method with a semi-closed analytical method of multiple scattering developed for an array composed of vertical cylindrical structures. This analytical method had a limitation owing to the geometry of many offshore structures including, e.g., the Mobile...

Yu, Xiaochuan

2012-10-19T23:59:59.000Z

451

Simulating the Biogeochemical and Biogeophysical Impacts of Transient Land Cover Change and Wood Harvest in the Community Climate System Model (CCSM4) from 1850 to 2100  

E-Print Network [OSTI]

To assess the climate impacts of historical and projected land cover change in the Community Climate System Model, version 4 (CCSM4), new time series of transient Community Land Model, version 4 (CLM4) plant functional ...

Lawrence, Peter J.; Feddema, Johannes J.; Bonan, Gordon B.; Meehl, Gerald A.; O’ Neill, Brian C.; Oleson, Keith W.; Levis, Samuel; Lawrence, David M.; Kluzek, Erik; Lindsay, Keith

2012-05-01T23:59:59.000Z

452

Ownership transfer for non-federate object and time management in developing an hla compliant logistics model.  

SciTech Connect (OSTI)

A seaport simulation model, PORTSIM, has been developed for the Department of Defense (DOD) at Argonne National Laboratory. PORTSIM simulates the detailed processes of cargo loading and unloading in a seaport and provides throughput capability, resource utilization, and other important information on the bottlenecks in a seaport operation, which are crucial data in determining troop and equipment deployment capability. There are two key problems to solve in developing the HLA-compliant PORTSIM model. The first is the cargo object ownership transfer problem. In PORTSIM, cargo items, e.g. vehicles, containers, and pallets, are objects having asset attributes. Cargo comes to a seaport for loading or unloading. The ownership of a cargo object transfers from its carrier to the port and then from the port to a new carrier. Each owner of the cargo object is responsible for publishing and updating the attributes of the cargo object when it has the ownership. This creates a unique situation in developing the PORTSIM federate object model, that is, the ownership of the object instead of the attributes needs to be changed in handling the cargo object in the PORTSIM federate. The ownership management service provided by the current RTI does not directly address this issue. The second is the time management issue. PORTSIM is an event-driven simulation that models seaport operations over time. To make PORTSIM HLA compliant, time management must be addressed to allow for synchronization with other simulation models. This paper attempts to address these two issues and methodologies developed for solving these two problems.

Li, Z.

1998-01-12T23:59:59.000Z

453

Modeling and simulation of blast-induced, early-time intracranial wave physics leading to traumatic brain injury.  

SciTech Connect (OSTI)

The objective of this modeling and simulation study was to establish the role of stress wave interactions in the genesis of traumatic brain injury (TBI) from exposure to explosive blast. A high resolution (1 mm{sup 3} voxels), 5 material model of the human head was created by segmentation of color cryosections from the Visible Human Female dataset. Tissue material properties were assigned from literature values. The model was inserted into the shock physics wave code, CTH, and subjected to a simulated blast wave of 1.3 MPa (13 bars) peak pressure from anterior, posterior and lateral directions. Three dimensional plots of maximum pressure, volumetric tension, and deviatoric (shear) stress demonstrated significant differences related to the incident blast geometry. In particular, the calculations revealed focal brain regions of elevated pressure and deviatoric (shear) stress within the first 2 milliseconds of blast exposure. Calculated maximum levels of 15 KPa deviatoric, 3.3 MPa pressure, and 0.8 MPa volumetric tension were observed before the onset of significant head accelerations. Over a 2 msec time course, the head model moved only 1 mm in response to the blast loading. Doubling the blast strength changed the resulting intracranial stress magnitudes but not their distribution. We conclude that stress localization, due to early time wave interactions, may contribute to the development of multifocal axonal injury underlying TBI. We propose that a contribution to traumatic brain injury from blast exposure, and most likely blunt impact, can occur on a time scale shorter than previous model predictions and before the onset of linear or rotational accelerations traditionally associated with the development of TBI.

Ford, Corey C. (University of New Mexico, Albuquerque, NM); Taylor, Paul Allen

2008-02-01T23:59:59.000Z

454

1INFORMS 10/04 RegularRegular Variation and Financial TimeVariation and Financial Time  

E-Print Network [OSTI]

financial time series IBM returns Multiplicative models for log-returns (GARCH, SV) Regular variation variation Stochastic recurrence equations (GARCH) Point process convergence Extremes and extremal index for volatility: (i) GARCH(p,q) process (General AutoRegressive Conditional Heteroscedastic

455

Continuous-time model reference adaptive control with improved transient performance  

E-Print Network [OSTI]

. . 10 3. 1. Introduction . . 3. 2. Performance of a Standard MRAC Scheme. . . . . . . . . 3. 3. Performance Improvement as Input Disturbance Rejection 3. 4. A Modified MRAC Scheme for Improved Transient Per- formance . 3. 5. Example and Simulations... 10 13 16 21 24 IV MODEL REFERENCE ADAPTIVE CONTROL OF RIGID ROBOTS WITH IMPROVED TRANSIENT PERFORMANCE 27 4. 1. Introduction 4. 2. Performance of a Standard MRAC Scheme for a Robotic Manipulator . 4. 3. Performance Improvement as Input...

Ho, Ming-Tzu

1993-01-01T23:59:59.000Z

456

Observation of Discrete Oscillations in a Model-independent Plot of Cosmological Scale Factor vs. Lookback Time and a Scalar Field Model  

E-Print Network [OSTI]

We have observed damped longitudinal cosmological-scale oscillations in a unique model-independent plot of scale factor against lookback time for Type Ia supernovae data. We found several first-derivative relative maxima/minima spanning the range of reported transition-redshifts. These extrema comprise 2 full cycles with a period of approximately 0.15 Hubble times (H0=68 km/s/Mpc). This period corresponds to a fundamental frequency of approximately 7 cycles over the Hubble time. Transition-z values quoted in the literature generally fall near these minima and may explain the reported wide spread up to the predicted LCDM value of approximately z = 0.77. We also observe second and third harmonics of the fundamental. The scale factor data is analyzed several different ways including smoothing, Fourier transform and autocorrelation. We propose a cosmological scalar field harmonic oscillator model for the observation. On this time scale, for a quantum scalar field, the scalar field mass is extraordinarily small at...

Ringermacher, H I

2015-01-01T23:59:59.000Z

457

Time evolution of electron flow in a model diode: Non-perturbative analysis  

SciTech Connect (OSTI)

Using a combination of Eulerian and Lagrangian variables we study the time evolution of the electron flow from a no-current state to a final state with the stationary current in a planar one-dimensional diode. The electrons can be injected externally or generated by the cathode via field emission governed by a current-field law. The initial zero current regime is replaced suddenly by injection or, in the case of field emission, by jumping the anode voltage from zero to a constant positive value. The case of equipotential electrodes and fixed injection is studied along with a positive anode potential. When the current is fixed externally, the approach to the stationary state goes without oscillations if the initial electron velocity is high enough and the anode can absorb the injected flow. Otherwise the accumulated space charge creates a potential barrier which reflects the flow and leads to its oscillations, but our method of analysis is invalid in such conditions. In the field emission case the flow goes to its stationary state through a train of decaying oscillations whose period is of the order of the electron transit time, in agreement with earlier studies based on perturbation techniques. Our approximate method does not permit very high cathode emissivity although the method works when the stationary current density is only about 10% smaller than the Child-Langmuir limit.

Rokhlenko, A.; Lebowitz, J. L. [Department of Mathematics, Rutgers University, Piscataway, New Jersey 08854-8019 (United States)

2013-12-21T23:59:59.000Z

458

Investigating a Fluctuating-accretion Model for the Spectral-timing Properties of Accreting Black Hole Systems  

E-Print Network [OSTI]

The fluctuating accretion model of Lyubarskii (1997) and its extension by Kotov et al. (2001), seeks to explain the spectral-timing properties of the X-ray variability of accreting black holes in terms of inward-propagating mass accretion fluctuations produced at a broad range of radii. The fluctuations modulate the X-ray emitting region as they move inwards and can produce temporal-frequency-dependent lags between energy bands, and energy-dependent power spectral densities (PSDs) as a result of the different emissivity profiles, which may be expected at different X-ray energies. Here we use a simple numerical implementation to investigate in detail the X-ray spectral-timing properties of the model and their relation to several physically interesting parameters, namely the emissivity profile in different energy bands, the geometrical thickness and viscosity parameter of the accretion flow, the strength of damping on the fluctuations and the temporal coherence (measured by the `quality-factor', Q) of the fluctuations introduced at each radius. We find that a geometrically thick flow with large viscosity parameter is favoured, and confirm that the predicted lags are quite robust to changes in the emissivity profile, and physical parameters of the accretion flow, which may help to explain the similarity of the lag spectra in the low/hard and high/soft states of Cyg X-1. We also demonstrate the model regime where the light curves in different energy bands are highly spectrally coherent. We compare model predictions directly to X-ray data from the Narrow Line Seyfert~1 galaxy NGC 4051 and the BHXRB Cyg X-1 in its high/soft state and show that this general scheme can reproduce simultaneously the time lags and energy-dependence of the PSD.

P. Arevalo; P. Uttley

2005-12-15T23:59:59.000Z

459

The summation of certain series  

E-Print Network [OSTI]

inf1nite series. As an 1llustration, it can be shown by one of the methods to be developed that the ser1es / / / Z converge s to the number 1. The number I, then, is said to be the sum, or value, of the ser1es wr1tten 1n the form of a closed... expression. As a second examole, consider the series, / / / + ? +. ? /2 gs ~z 7/* whose sum will be shown to be ? . Again the number 6 J 6 is sa1d to be a closed form for the sum of the given series. In this case, however, obJection might possibly...

Holder, Leonard Irvin

2012-06-07T23:59:59.000Z

460

Power Series Power series are one of the most useful type of series in analysis. For example,  

E-Print Network [OSTI]

Chapter 6 Power Series Power series are one of the most useful type of series in analysis functions (and many other less familiar functions). 6.1. Introduction A power series (centered at 0 coefficients. If all but finitely many of the an are zero, then the power series is a polynomial function

Hunter, John K.

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


461

Solar Permitting & Inspection Webinar Series  

Office of Energy Efficiency and Renewable Energy (EERE)

ICLEI Local Governments for Sustainability U.S.A. and the Interstate Renewable Energy Council, Inc. (IREC) present a series of three webinars on Solar Permitting & Inspection. As part of the U...

462

ECOLOGY AND EVOLUTION SEMINAR SERIES*  

E-Print Network [OSTI]

ECOLOGY AND EVOLUTION SEMINAR SERIES* WINTER 2013 ECL 296 (CRN 50337) / PBG 292 (CRN 64677 24 The Modern Ecology of Ice-Covered Lakes in Antarctica: A Journey Back JANUARY 31 Lizards in an Evolutionary Tree: Ecology and Adaptive Radiation

Ishida, Yuko

463

Castle series, 1954. Technical report  

SciTech Connect (OSTI)

CASTLE was an atmospheric nuclear weapons test series held in the Marshall Islands at Enewetak and Bikini atolls in 1954. This is a report of DOD peronnel in CASTLE with an emphasis on operations and radiological safety.

Martin, E.J.; Rowland, R.H.

1982-04-01T23:59:59.000Z

464

Modeling of on-line catalyst addition effects in a short contact time reactor  

SciTech Connect (OSTI)

Recently developed short-contact-time reactors (SCTR), consisting of porous alumina monoliths coated with platinum, have been shown to produce ethylene from rich ethane/oxygen(hydrogen) mixtures with yields and selectivities comparable to conventional steam cracking, using a reactor of much smaller size. Although the overall mechanism is clearly autothermal and catalytic, the details, in particular the relative contributions of heterogeneous and homogeneous chemistry, are a matter of considerable debate. Recent experiments show that reactor performance can be further enhanced by dripping a dilute platinum solution onto the SCTR front face during reaction, resulting in catalyst deposition within only a short (several millimeter) zone of the reactor. The authors have undertaken a computational study of this system, using two-dimensional computational fluid dynamics simulations with full heat and mass transport and detailed heterogeneous and homogeneous kinetic mechanisms. The results indicate that front-face catalyst loading enhances reactor performance by limiting the opportunity for heterogeneous ethane reactions that produce methane. As a result, ethylene selectivity increases and CH{sub 4} selectivity decreases. The results strongly support a mechanism recently proposed by the authors, in which rapid, heterogeneous oxidation of adsorbed hydrogen consumes most of the oxygen. The resulting heat is then released to the gas phase, causing homogeneous pyrolysis of ethane to occur in an environment containing much less oxygen. This mechanism explains not only the effects of on-line catalyst addition, but also the increase in ethylene selectivity observed upon addition of hydrogen to the reactant mixture.

D. K. Zerkle; M. d. Allendorf; M. Wolf; O. Deutschmann

2000-07-30T23:59:59.000Z

465

Joint Seasonal ARMA Approach for Modeling of Load Forecast Errors in Planning Studies  

SciTech Connect (OSTI)

To make informed and robust decisions in the probabilistic power system operation and planning process, it is critical to conduct multiple simulations of the generated combinations of wind and load parameters and their forecast errors to handle the variability and uncertainty of these time series. In order for the simulation results to be trustworthy, the simulated series must preserve the salient statistical characteristics of the real series. In this paper, we analyze day-ahead load forecast error data from multiple balancing authority locations and characterize statistical properties such as mean, standard deviation, autocorrelation, correlation between series, time-of-day bias, and time-of-day autocorrelation. We then construct and validate a seasonal autoregressive moving average (ARMA) model to model these characteristics, and use the model to jointly simulate day-ahead load forecast error series for all BAs.

Hafen, Ryan P.; Samaan, Nader A.; Makarov, Yuri V.; Diao, Ruisheng; Lu, Ning

2014-04-14T23:59:59.000Z

466

Michigan Institute for Plasma Science and Engineering Fall 2011 Seminar Series  

E-Print Network [OSTI]

Michigan Institute for Plasma Science and Engineering Fall 2011 Seminar Series Date, Time EECS Dr. Joe Borovsky AOSS and Los Alamos National Laboratory The Solar Wind Plasma Wednesday

Shyy, Wei

467

Efficient market model: within-sample fit versus out-of-sample forecasts  

E-Print Network [OSTI]

has been the center of considerable attention in the applied econometric literature. The criterion Predictive Least Squares (PLS) based on actual postsample forecasting performance is proposed to identify a time series model. The criterion is applied...

Cheng, Chi

1993-01-01T23:59:59.000Z

468

Mimicking acceleration in the constant-bang-time Lemaître -- Tolman model: Shell crossings, density distributions and light cones  

E-Print Network [OSTI]

The Lema\\^{\\i}tre -- Tolman model with $\\Lambda = 0$ and constant bang time that imitates the luminosity distance -- redshift relation of the $\\Lambda$CDM model using the energy function $E$ alone contains shell crossings. In this paper, the location in spacetime and the consequences of existence of the shell-crossing set (SCS) are investigated. The SCS would come into view of the central observer only at $t \\approx 1064 T$ to the future from now, where $T$ is the present age of the Universe, but would not leave any recognizable trace in her observations. Light rays emitted near to the SCS are blueshifted at the initial points, but the blueshift is finite, and is overcompensated by later-induced redshifts if the observer is sufficiently far. The local blueshifts cause that $z$ along a light ray is not a monotonic function of the comoving radial coordinate $r$. As a consequence, the angular diameter distance $D_A$ and the luminosity distance $D_L$ from the central observer fail to be functions of $z$; the relations $D_A(z)$ and $D_L(z)$ are multiple-valued in a vicinity of the SCS. The following quantities are calculated and displayed: (1) The distribution of mass density on a few characteristic hypersurfaces of constant time; some of them intersect the SCS. (2) The distribution of density along the past light cone of the present central observer. (3) A few light cones intersecting the SCS at characteristic instants. (4) The redshift profiles along several light cones. (5) The extremum-redshift hypersurface. (6) The $D_A(z)$ and $D_L(z)$ relations. (7) The last scattering time and its comparison with the $\\Lambda$CDM last scattering epoch.

Andrzej Krasi?ski

2014-09-10T23:59:59.000Z

469

Nobel Lecture Series Videos Now Available Online  

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

Lecture Series Videos Now Available Online Nobel Lecture Videos Now Available Online May 29, 2014 by Kathy Kincade (0 Comments) Three of the NERSC Nobel Lecture Series videos --...

470

Deriving emissions time series from sparse atmospheric mole fractions  

E-Print Network [OSTI]

A growth-based Bayesian inverse method is presented for deriving emissions of atmospheric trace species from temporally sparse measurements of their mole fractions. This work is motivated by many recent studies that have ...

Rigby, Matthew

471

Time Series of Trace Element Concentrations Calculated from  

E-Print Network [OSTI]

a). A total of 120 samples were collected at sites within the Bay, outside the Golden Gate receives many waste water discharges, especially in areas south of the Dumbarton Bridge, that contain trace

472

Star Formation through Time ASP Conference Series, Vol. **VOLUME**, 2003  

E-Print Network [OSTI]

, probably a featureless power law (or closely related componenets such as scattered nuclear light and to the presence of a young stellar population in the nuclear regions of many Seyferts. 1. Introduction and Observations The origin of the nuclear continuum light in Seyferts has received much attention over the years

Whittle, Mark

473

Online Discovery and Maintenance of Time Series Motifs Abdullah Mueen  

E-Print Network [OSTI]

the performance of data center chillers, and reported "switching from motif 8 to motif 5 gives us a nearly $40

Zordan, Victor

474

Learning from Time Series in the Resource-Limited Situations  

E-Print Network [OSTI]

selected) with the utility function (line 7), picks thewith highest utility and pushes it onto T (lines 8 to 10).utility of that candidate by calling C ALCULATE I NFOR - MATION G AIN () (line

Ye, Lexiang

2010-01-01T23:59:59.000Z

475

Rare Time Series Motif Discovery from Unbounded Streams  

E-Print Network [OSTI]

station's solar panel [2], only a fraction of which we can buffer. A pattern we are observing now seems repeated behavior in a dataset with ten million items, and we wish to discover them. We could employ the MK

Zordan, Victor

476

Events, Neural Systems and Time Series Leslie Smith1  

E-Print Network [OSTI]

Bizarro4 1 Computing Science and Mathematics, School of Natural Sciences, University of Stirling, Stirling Informatics Engineering Department, University of Coimbra, 3030-290 Coimbra, Portugal Abstract. Different

Smith, Leslie S.

477

Symbolic analysis of non-stationary time series  

E-Print Network [OSTI]

/control of period doubling bifurcations in internal combustion engines, classification of dynamics of fluidized bed, the system loses stability at some tfixed point unstable fixed point #12;Sherwood Meeting, Atlanta, March 1999 8 )t(r),t())t(,r(fr +-=+= 2&& ),r(f c

Tracy, Eugene R.

478

Symbolic Dynamic Analysis of Transient Time Series for Fault  

E-Print Network [OSTI]

. A recently developed data-driven technique, called the symbolic dynamic filtering (SDF) [8], has been shown), and Bayesian techniques [9]. Recently, in a two-part paper [10,11], an SDF-based algorithm for detection- stationarity made in SDF. Due to this assumption, SDF may not be able to adequately handle transient data

Ray, Asok

479

Spectral Analysis of Univariate and Bivariate Time Series  

E-Print Network [OSTI]

be nonnegative, and hence the sdf SX(·) is a nonnegative function of frequency. Large values of the sdf tell us glossed over many details here, including the fact that a `proper' sdf does not exist for some stationary] for a heuristic development.) Because {Xt} is a real-valued process, the sdf is an even function; i.e., SX

Percival, Don

480

Game-theoretically Optimal Reconciliation of Contemporaneous Hierarchical Time Series  

E-Print Network [OSTI]

of its applications to, among others, inventory manage- ment for companies [Fliedner, 1999], euro-area], which is essential for electricity companies to reduce electricity production cost and take advantage) reconciliation method, which is guaranteed to only improve any given set of forecasts. This opens up new possibil

Paris-Sud XI, Université de

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481

Model-free measure of coupling from embedding principle  

E-Print Network [OSTI]

A model-free measure of coupling between dynamical variables is built from time series embedding principle. The approach described does not require a mathematical form for the dynamics to be assumed. The approach also does not require density estimation which is an intractable problem in high dimensions. The measure has strict asymptotic bounds and is robust to noise. The proposed approach is used to demonstrate coupling between complex time series from the finance world.

Chetan Nichkawde

2014-02-17T23:59:59.000Z

482

A Spatiotemporal Graph Model for Rainfall Event Identification and Representation  

E-Print Network [OSTI]

of a storm ? The spread of a wildfire ? Other dynamic geographic phenomena from time series of snapshot datasets 3Research Objectives Identify the whole lifecycle of rainstorms from time series of snapshot datasets; Represent and analyze the rainstorms... based on a spatiotemporal graph model; Analyze the spatiotemporal characteristics of rainstorms. Data ? NEXRAD (Next generation Radar) ? Hourly precipitation estimate ? Cover more than 2/3 of the nation Rainstorms’ Lifecycle Identification Delineate...

Liu, Weibo

2014-04-21T23:59:59.000Z

483

Budgets and behaviors of uranium and thorium series isotopes in the Santa Monica Basin off the California Coast  

SciTech Connect (OSTI)

Samples from three time-series sediment traps deployed in the Santa Monica Basin off the California coast were analyzed to study the flux and scavenging of uranium and thorium series isotopes. Variations of uranium and thorium series isotopes fluxes in the water column were obtained by integrating these time-series deployment results. Mass and radionuclide fluxes measured from bottom sediment traps compare favorably with fluxed determined from sediment core data. This agreement suggests that the near-bottom sediment traps are capable of collecting settling particles representative of the surface sediment. The phase distributions of {sup 234}Th in the water column were calculated by an inverse method using sediment trap data, which help to study the variations of {sup 234}Th scavenging in the water column. Scavenging and radioactive decay of {sup 234}Th are the two principal processes for balancing {sup 234}Th budget in the water column. The residence times of dissolved and particulate {sup 234}Th were determined by a {sup 234}Th scavenging model.

Yu, Lei

1991-12-16T23:59:59.000Z

484

SERI advanced wind turbine blades  

SciTech Connect (OSTI)

The primary goal of the Solar Energy Research Institute`s (SERI) advanced wind turbine blades is to convert the kinetic energy in the wind into mechanical energy in an inexpensive and efficient manner. To accomplish this goal, advanced wind turbine blades have been developed by SERI that utilize unique airfoil technology. Performance characteristics of the advanced blades were verified through atmospheric testing on fixed-pitch, stall-regulated horizontal-axis wind turbines (HAWTs). Of the various wind turbine configurations, the stall-regulated HAWT dominates the market because of its simplicity and low cost. Results of the atmospheric tests show that the SERI advanced blades produce 10% to 30% more energy than conventional blades. 6 refs.

Tangler, J.; Smith, B.; Jager, D.

1992-02-01T23:59:59.000Z

485

SERI advanced wind turbine blades  

SciTech Connect (OSTI)

The primary goal of the Solar Energy Research Institute's (SERI) advanced wind turbine blades is to convert the kinetic energy in the wind into mechanical energy in an inexpensive and efficient manner. To accomplish this goal, advanced wind turbine blades have been developed by SERI that utilize unique airfoil technology. Performance characteristics of the advanced blades were verified through atmospheric testing on fixed-pitch, stall-regulated horizontal-axis wind turbines (HAWTs). Of the various wind turbine configurations, the stall-regulated HAWT dominates the market because of its simplicity and low cost. Results of the atmospheric tests show that the SERI advanced blades produce 10% to 30% more energy than conventional blades. 6 refs.

Tangler, J.; Smith, B.; Jager, D.

1992-02-01T23:59:59.000Z

486

Why perform time-lapse seismic monitoring? Is it to ver-ify the reservoir model? No! We should conduct time-lapse  

E-Print Network [OSTI]

the Teal South time-lapse multicomponent (4-D/4-C) study, in Eugene Island Block 354 in the Gulf of Mexico by Texaco, has been continued through a consortium organized by the Energy Research Clearing House. Some

487

Frontiers in Science Lecture Series  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsruc DocumentationP-SeriesFlickr Flickr Editor's note:Computing | Argonne LeadershipLecture Series

488

Conditional Markov regime switching model applied to economic modelling.  

E-Print Network [OSTI]

and Brent oil price) to show that this modelling well identifies both mean reverting and volatility regimes times series data as business cycle, economic growth or unemployment is not new. In his seminal paper [7 to reproduce the different phase of the business cycles and captures the cyclical behavior of the U.S. GDP

Paris-Sud XI, Université de

489

JMLR: Workshop and Conference Proceedings 12 (2011) 115139 Causality in Time Series Time Series Analysis with the Causality Workbench  

E-Print Network [OSTI]

, smoking and coughing might be both predictive of respiratory disease and helpful for diagnosis purposes. However, if smoking is a cause and coughing a conse- quence, acting on the cause (smoking) can change your health status, but not acting on the symptom or consequence (coughing). Thus it is extremely important

Statnikov, Alexander

490

The Multi-Stage Investment Timing Game in Offshore Petroleum Production: Preliminary results from an econometric model  

E-Print Network [OSTI]

robustness checks from the econometric model coefficients inPreliminary results from an econometric model C. -Y.paper uses a structural econometric model to analyze the

Lin, C.-Y. Cynthia

2007-01-01T23:59:59.000Z

491

ACCESSCCESS MARINE ECOLOGY PROGRESS SERIES  

E-Print Network [OSTI]

OPENPEN ACCESSCCESS MARINE ECOLOGY PROGRESS SERIES Mar Ecol Prog Ser Vol. 458: 39­52, 2012 doi: 10 and the instability or unpre- dictability of disturbance. Global warming is expec- ted to increase the vulnerability. 2010, Gruber 2011). Much of the available information about the impact on benthic systems comes

Zuschin, Martin

492

2014-2015Series Engineering  

E-Print Network [OSTI]

2014-2015Series College of Engineering University of Kentucky is accredited by the Southern of Kentucky. The curriculum in biosystems engineering is administered jointly by the College of Engineering and the College of Agriculture. Graduates earn the Bachelor of Science in Biosystems Engineering degree

MacAdam, Keith

493

2014-2015Series Engineering  

E-Print Network [OSTI]

of the College of Engineering. Freshman Year First Semester Hours EE 101 Creativity and Design in Electrical2014-2015Series College of Engineering University of Kentucky is accredited by the Southern of Kentucky. Electrical Engineering The undergraduate electrical engineering degree program seeks to produce

MacAdam, Keith

494

2012-2013 Series Engineering  

E-Print Network [OSTI]

.................................................................................... 4 EE 101 Creativity and Design in Electrical and Computer Engineering or CS 100 The Computer Science2012-2013 Series College of Engineering University of Kentucky is accredited by the Southern://www.sacscoc.org for questions about the accreditation of University of Kentucky. ComputerEngineering Computer engineering

Dietz, Henry G. "Hank"

495

Small Flock Poultry Management Series  

E-Print Network [OSTI]

to care for your chicks in advance of them arriving at your home. Newly hatched chicks can not control (water splashed on the hot bulb will shatter it); Where possible use a `Hard Glass' bulb Family, HomeSmall Flock Poultry Management Series Brooding Chicks Starting your chicks Raising a flock

New Hampshire, University of

496

Mechanical Engineering Department Seminar Series  

E-Print Network [OSTI]

Mechanical Engineering Department Seminar Series Rational Mechanics of Viral Shells: Is Continuum Theory a Stretch? William S. Klug Associate Professor, Mechanical & Aerospace Engineering, University-assembly. The capacity of these shells to respond structurally and mechanically to physical and chemical stimuli also

Eustice, Ryan

497

Mechanical Engineering Department Seminar Series  

E-Print Network [OSTI]

­Madison as an Honorary Fellow in 2012 after retiring from General Motors Research & DevelopmentMechanical Engineering Department Seminar Series Ignition and Flame Growth in Spray-Guided Stratified-Charge Gasoline Engines Dr. Todd Fansler Engine Research Center University of Wisconsin - Madison

Papalambros, Panos

498

Autoregressive modeling with state-space embedding vectors for damage detection under operational and environmental variability  

SciTech Connect (OSTI)

A nonlinear time series approach is presented to detect damage in systems by using a state-space reconstruction to infer the geometrical structure of a deterministic dynamical system from observed time series response at multiple locations. The unique contribution of this approach is using a Multivariate Autoregressive (MAR) model of a baseline condition to predict the state space, where the model encodes the embedding vectors rather than scalar time series. A hypothesis test is established that the MAR model will fail to predict future response if damage is present in the test condition, and this test is investigated for robustness in the context of operational and environmental variability. The applicability of this approach is demonstrated using acceleration time series from a base-excited 3-story frame structure.

Farrar, Charles [Los Alamos National Laboratory; Figueiredo, Eloi [UNIV OF PORTO; Todd, Michael [UCSD; Flynn, Eric [UCSD

2010-01-01T23:59:59.000Z

499

Consistent perturbative treatment of the subohmic spin-boson model yielding arbitrarily small $T_2/T_1$ decoherence time ratios  

E-Print Network [OSTI]

We present a perturbative treatment of the subohmic spin-boson model which remedies a crucial flaw in previous treatments. The problem is traced back to the incorrect application of a Markov type approximation to specific terms in the temporal evolution of the reduced density matrix. The modified solution is consistent both with numerical simulations and the exact solution obtained when the bath-coupling spin-space direction is parallel to the qubit energy-basis spin. We therefore demonstrate that %in distinction to previous findings the subohmic spin-boson model is capable of %consistently describing arbitrarily small %(less than two) ratios of the $T_2$ and $T_1$ decoherence times, associated to the decay of the off-diagonal and diagonal reduced density-matrix elements, respectively. An analytical formula for $T_2/T_1$ at the absolute zero of temperature is provided in the limit of a subohmic bath with vanishing spectral power law exponent. Small ratios closely mimic the experimental results for solid state (flux) qubits, which are subject predominantly to low-frequency electromagnetic noise, and we suggest a reanalysis of the corresponding experimental data in terms of a $nonanalytic$ decay of off-diagonal coherence.

Kyung-Joo Noh; Uwe R. Fischer

2014-12-09T23:59:59.000Z

500

AMPS, a real-time mesoscale modeling system, has provided a decade of service for scientific and logistical needs and has helped advance polar numerical weather prediction  

E-Print Network [OSTI]

and logistical needs and has helped advance polar numerical weather prediction as well as understanding support for the USAP. The concern at the time was the numerical weather prediction (NWP) guidance-time implementation of the Weather Research and Forecasting model (WRF; Skamarock et al. 2008) to support the U

Howat, Ian M.