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Georgia Tech
1.
Diaz-Mercado, Yancy J.
Interactions in multi-robot systems.
Degree: PhD, Electrical and Computer Engineering, 2016, Georgia Tech
URL: http://hdl.handle.net/1853/55020
► The objective of this research is to develop a framework for multi-robot coordination and control with emphasis on human-swarm and inter-agent interactions. We focus on…
(more)
▼ The objective of this research is to develop a framework for multi-robot coordination and control with emphasis on human-swarm and inter-agent interactions. We focus on two problems: in the first we address how to enable a single human operator to externally influence large teams of robots. By directly imposing
density functions on the environment, the user is able to abstract away the size of the swarm and manipulate it as a whole, e.g., to achieve specified geometric configurations, or to maneuver it around. In order to pursue this approach, contributions are made to the problem of
coverage of
time-
varying density functions. In the second problem, we address the characterization of inter-agent interactions and enforcement of desired interaction patterns in a provably safe (i.e., collision free) manner, e.g., for achieving rich motion patterns in a shared space, or for mixing of sensor information. We use elements of the braid group, which allows us to symbolically characterize classes of interaction patterns. We further construct a new specification language that allows us to provide rich, temporally-layered specifications to the multi-robot mixing framework, and present algorithms that significantly reduce the search space of specification-satisfying symbols with exactness guarantees. We also synthesize provably safe controllers that generate and track trajectories to satisfy these symbolic inputs. These controllers allow us to find bounds on the amount of safe interactions that can be achieved in a given bounded domain.
Advisors/Committee Members: Egerstedt, Magnus (advisor), Wardi, Yorai (committee member), Yezzi, Anthony (committee member), Ames, Aaron D. (committee member), Zhou, Hao Min (committee member).
Subjects/Keywords: Multi-robot control; Human-swarm interactions; Coverage control; Coverage of time-varying density functions; Braids; Multi-robot mixing; Inter-robot interactions; Mixing limit; Symbolic motion planning
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APA (6th Edition):
Diaz-Mercado, Y. J. (2016). Interactions in multi-robot systems. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/55020
Chicago Manual of Style (16th Edition):
Diaz-Mercado, Yancy J. “Interactions in multi-robot systems.” 2016. Doctoral Dissertation, Georgia Tech. Accessed March 01, 2021.
http://hdl.handle.net/1853/55020.
MLA Handbook (7th Edition):
Diaz-Mercado, Yancy J. “Interactions in multi-robot systems.” 2016. Web. 01 Mar 2021.
Vancouver:
Diaz-Mercado YJ. Interactions in multi-robot systems. [Internet] [Doctoral dissertation]. Georgia Tech; 2016. [cited 2021 Mar 01].
Available from: http://hdl.handle.net/1853/55020.
Council of Science Editors:
Diaz-Mercado YJ. Interactions in multi-robot systems. [Doctoral Dissertation]. Georgia Tech; 2016. Available from: http://hdl.handle.net/1853/55020

Texas A&M University
2.
Qian, Yanjun.
Data Science Methods for Analyzing Nanomaterial Images and Videos.
Degree: PhD, Industrial Engineering, 2018, Texas A&M University
URL: http://hdl.handle.net/1969.1/173896
► A large amount of nanomaterial characterization data has been routinely collected by using electron microscopes and stored in image or video formats. A bottleneck in…
(more)
▼ A large amount of nanomaterial characterization data has been routinely collected by
using electron microscopes and stored in image or video formats. A bottleneck in making
effective use of the image/video data is the lack of the development of sophisticated
data science methods capable of unlocking valuable material pertinent information buried
in the raw data. To address this problem, the research of this dissertation begins with
understanding the physical mechanisms behind the concerned process to determine why
the generic methods fall short. Afterwards, it designs and improves image processing
and statistical modeling tools to address the practical challenges. Specifically, this dissertation
consists of two main tasks: extracting useful information from images or videos
of nanomaterials captured by electron microscopes, and designing analytical methods for
modeling/monitoring the dynamic growth of nanoparticles. In the first task, a two-pipeline
framework is proposed to fuse two kinds of image information for nanoscale object detection
that can accurately identify and measure nanoparticles in transmission electron
microscope (TEM) images of high noise and low contrast. To handle the second task of
analyzing nanoparticle growth, this dissertation develops dynamic nonparametric models
for
time-
varying probability
density functions (PDFs) estimation. Unlike simple statistics,
a PDF contains fuller information about the nanoscale objects of interests. Characterizing
the dynamic changes of the PDF as the nanoparticles grow into different sizes and
morph into different shapes, the proposed nonparametric methods are capable of analyzing
an in situ TEM video to delineate growth stages in a retrospective analysis, or tracking
the nanoparticle growth process in a prospective analysis. The resulting analytic methods
have applications in areas beyond the nanoparticle growth process such as the image-based
process control tasks in additive manufacturing.
Advisors/Committee Members: Ding, Yu (advisor), Huang, Jianhua (advisor), Bukkapatnam, Satish (committee member), Liang, Hong (committee member).
Subjects/Keywords: In situ TEM video; nanoparticle growth process; change point detection; time-varying probability density functions estimation
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Qian, Y. (2018). Data Science Methods for Analyzing Nanomaterial Images and Videos. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/173896
Chicago Manual of Style (16th Edition):
Qian, Yanjun. “Data Science Methods for Analyzing Nanomaterial Images and Videos.” 2018. Doctoral Dissertation, Texas A&M University. Accessed March 01, 2021.
http://hdl.handle.net/1969.1/173896.
MLA Handbook (7th Edition):
Qian, Yanjun. “Data Science Methods for Analyzing Nanomaterial Images and Videos.” 2018. Web. 01 Mar 2021.
Vancouver:
Qian Y. Data Science Methods for Analyzing Nanomaterial Images and Videos. [Internet] [Doctoral dissertation]. Texas A&M University; 2018. [cited 2021 Mar 01].
Available from: http://hdl.handle.net/1969.1/173896.
Council of Science Editors:
Qian Y. Data Science Methods for Analyzing Nanomaterial Images and Videos. [Doctoral Dissertation]. Texas A&M University; 2018. Available from: http://hdl.handle.net/1969.1/173896

The Ohio State University
3.
Ganguly, Shreyan.
Modeling Nonstationarity Using Locally Stationary Basis
Processes.
Degree: PhD, Statistics, 2019, The Ohio State University
URL: http://rave.ohiolink.edu/etdc/view?acc_num=osu1563408374215259
► Methods of estimation and forecasting for stationary models are well known and straightforward in classical time series analysis. For this reason, time series analysis involves…
(more)
▼ Methods of estimation and forecasting for stationary
models are well known and straightforward in classical
time series
analysis. For this reason,
time series analysis involves using
mathematical transformations to render the stochastic process
approximately stationary and conduct inference on the transformed
series. However, assuming stationarity, even for the transformed
series, is at best an idealization. In practice, this assumption
may be unrealistic, especially for processes with
time varying
statistical properties. We define a class of locally stationary
processes called locally stationary basis (LSB) processes which can
lead to more accurate uncertainty quantification over making an
invalid assumption of stationarity. LSB processes assumes the model
parameters to be
time-
varying and parameterizes them in terms of a
transformation of basis
functions. The transformation is required
as it ensures that the processes are locally stationary, and as
required, causal, invertible or identifiable, something that is
generally ignored while defining locally stationary models. We
develop methods and theory for parameter estimation in this class
of models, and propose a test that allow us to examine certain
departures from stationarity. We assess our methods using
simulation studies and apply these techniques to the analysis of an
electroencephalogram
time series. We also extend our theory for LSB
processes to the spatio-temporal case, in particular, LSB
spatio-temporal processes. While there are several models in
literature which explore the non-stationarities in the spatial
domain, few have been developed for non-stationarities in
time,
while still maintaining space-
time interactions. We give an
overview of the theory for LSB processes and provide a Bayesian
framework for carrying out inference with such models along with
spatial predictions. A suitable algorithm is proposed for efficient
posterior simulation for this class of models. We use this model to
for an analysis of the monthly mean temperatures from the Global
Historical Climatology Network data in and around the state of
Ohio, USA from 1905-2004.
Advisors/Committee Members: Craigmile, Peter (Advisor).
Subjects/Keywords: Statistics; Time varying processes; Basis functions; Tests of stationarity; Causality; Parameter estimation; Uncertainty quantification; EEG; Mean temperatures; Climate data; Bayesian; MCMC
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Ganguly, S. (2019). Modeling Nonstationarity Using Locally Stationary Basis
Processes. (Doctoral Dissertation). The Ohio State University. Retrieved from http://rave.ohiolink.edu/etdc/view?acc_num=osu1563408374215259
Chicago Manual of Style (16th Edition):
Ganguly, Shreyan. “Modeling Nonstationarity Using Locally Stationary Basis
Processes.” 2019. Doctoral Dissertation, The Ohio State University. Accessed March 01, 2021.
http://rave.ohiolink.edu/etdc/view?acc_num=osu1563408374215259.
MLA Handbook (7th Edition):
Ganguly, Shreyan. “Modeling Nonstationarity Using Locally Stationary Basis
Processes.” 2019. Web. 01 Mar 2021.
Vancouver:
Ganguly S. Modeling Nonstationarity Using Locally Stationary Basis
Processes. [Internet] [Doctoral dissertation]. The Ohio State University; 2019. [cited 2021 Mar 01].
Available from: http://rave.ohiolink.edu/etdc/view?acc_num=osu1563408374215259.
Council of Science Editors:
Ganguly S. Modeling Nonstationarity Using Locally Stationary Basis
Processes. [Doctoral Dissertation]. The Ohio State University; 2019. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=osu1563408374215259

Kansas State University
4.
Kayode, Ajewole Martins.
Essays on
feeder cattle market dynamics.
Degree: PhD, Department of Agricultural
Economics, 2019, Kansas State University
URL: http://hdl.handle.net/2097/39613
► The United State has experienced a downward trend in cattle and calves marketing over the last decade. The gross income from cattle sales has been…
(more)
▼ The United State has experienced a downward trend in
cattle and calves marketing over the last decade. The gross income
from cattle sales has been in the opposite direction of inventory
recorded during this period. With changes in the cattle income over
the years, it is expected that the market will be changing over
time. This dissertation contains three related essays on feeder
cattle market dynamics. The first essay explores spatial arbitrage
opportunities in the feeder cattle markets across the United
States. The second essay examines the
time variation in the feeder
cattle spatial market connectedness. The third essay examine the
impact of the 2005 energy policy on the feeder cattle markets
through a
time-
varying analysis.
The objective of the first essay
is to determine the frequency of price differences in spatial
feeder cattle markets offer profitable arbitrage? The study further
investigates factors determining spatial arbitrage opportunities
between pairs of markets. Arbitrage opportunities are at the lowest
during the winter in the higher weight categories. The higher the
number of cattle head the higher the size of arbitrage
opportunities available between spatial markets. This study is the
first to use a
time-
varying transaction cost in the feeder cattle
market spatial analysis. The arbitrage information here will serve
as a guideline for potential investors in the feeder cattle market.
The major study limitation is that livestock is not a truly
homogenous product, and there are always at least minor differences
in animal prices within a market.
The second essay examines the
degree of connectedness of the feeder cattle markets in the United
States over
time. Spillover index measure are applied to capture
the impact of price shocks within selected feeder cattle markets on
market connectedness. The essay further evaluates the influence of
spatiotemporal factors that may impact the degree of market
connectedness over the same period, and the impact of drought on
periodic price transmission between markets. This is the first
study to apply a
time-
varying approach to study feeder cattle
market linkages at the auction level and factors influencing the
variation in market connectedness. Seven major auction markets
across five states are selected, three markets within the state of
Kansas and four markets outside Kansas. There is variation in the
level of market connectedness over the study period. Long term
drought severity accounts for some of the dynamics in the feeder
cattle market.
The third essay examines the
time path and
magnitude of volatility translation across major agricultural
commodities and energy markets and compares the causal
relationships between pre-ethanol boom and post-ethanol boom
periods. Results reveal strong evidence for
time variation in the
implied volatility spillover between the feeder cattle market and
the energy market. Despite a high correlation between crude oil and
feeder cattle volatilities in the post-ethanol boom period, the
linkage between the two commodities’…
Advisors/Committee Members: Ted C. Schroeder.
Subjects/Keywords: Feeder
cattle; Spatial
arbitrage; Market
connectedness;
Time-varying parameter; Implied
volatility; Drought
severity and coverage index
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Kayode, A. M. (2019). Essays on
feeder cattle market dynamics. (Doctoral Dissertation). Kansas State University. Retrieved from http://hdl.handle.net/2097/39613
Chicago Manual of Style (16th Edition):
Kayode, Ajewole Martins. “Essays on
feeder cattle market dynamics.” 2019. Doctoral Dissertation, Kansas State University. Accessed March 01, 2021.
http://hdl.handle.net/2097/39613.
MLA Handbook (7th Edition):
Kayode, Ajewole Martins. “Essays on
feeder cattle market dynamics.” 2019. Web. 01 Mar 2021.
Vancouver:
Kayode AM. Essays on
feeder cattle market dynamics. [Internet] [Doctoral dissertation]. Kansas State University; 2019. [cited 2021 Mar 01].
Available from: http://hdl.handle.net/2097/39613.
Council of Science Editors:
Kayode AM. Essays on
feeder cattle market dynamics. [Doctoral Dissertation]. Kansas State University; 2019. Available from: http://hdl.handle.net/2097/39613

University of Guelph
5.
Xin, Xin.
A STUDY OF TIES AND TIME-VARYING COVARIATES IN COX PROPORTIONAL HAZARDS MODEL.
Degree: MS, Department of Mathematics and Statistics, 2011, University of Guelph
URL: https://atrium.lib.uoguelph.ca/xmlui/handle/10214/2974
► In this thesis, ties and time-varying covariates in survival analysis are investigated. There are two types of ties: ties between event times (Type 1 ties)…
(more)
▼ In this thesis, ties and
time-
varying covariates in survival analysis are investigated. There are two types of ties: ties between event times (Type 1 ties) and ties between event times and the
time that discrete
time-
varying covariates change or "jump"(Type 2 ties). The Cox proportional hazards model is one of the most important regression models for survival analysis. Methods for including Type 1 ties and
time-
varying covariates in the Cox proportional hazards model are well established in previous studies, but Type 2 ties have been ignored in the literature. This thesis discusses the effect of Type 2 ties on Cox's partial likelihood, the current default method to treat Type 2 ties in statistical packages SAS and R (called Fail before Jump in this thesis), and proposes alternative methods (Random and Equally Weighted) for Type 2 ties. A simulation study as well as an analysis of data sets from real research both suggest that both Random and Equally Weighted methods perform better than the other two methods. Also the effect of the percentages of Type 1 and Type 2 ties on these methods for handling both types of ties is discussed.
Advisors/Committee Members: Darlington, Gerarda (advisor), Horrocks, Julie (advisor).
Subjects/Keywords: ties; time-varying covariates; Cox proportional hazards model; percentages of ties; simulation of time-varying survival data; survival analysis
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Xin, X. (2011). A STUDY OF TIES AND TIME-VARYING COVARIATES IN COX PROPORTIONAL HAZARDS MODEL. (Masters Thesis). University of Guelph. Retrieved from https://atrium.lib.uoguelph.ca/xmlui/handle/10214/2974
Chicago Manual of Style (16th Edition):
Xin, Xin. “A STUDY OF TIES AND TIME-VARYING COVARIATES IN COX PROPORTIONAL HAZARDS MODEL.” 2011. Masters Thesis, University of Guelph. Accessed March 01, 2021.
https://atrium.lib.uoguelph.ca/xmlui/handle/10214/2974.
MLA Handbook (7th Edition):
Xin, Xin. “A STUDY OF TIES AND TIME-VARYING COVARIATES IN COX PROPORTIONAL HAZARDS MODEL.” 2011. Web. 01 Mar 2021.
Vancouver:
Xin X. A STUDY OF TIES AND TIME-VARYING COVARIATES IN COX PROPORTIONAL HAZARDS MODEL. [Internet] [Masters thesis]. University of Guelph; 2011. [cited 2021 Mar 01].
Available from: https://atrium.lib.uoguelph.ca/xmlui/handle/10214/2974.
Council of Science Editors:
Xin X. A STUDY OF TIES AND TIME-VARYING COVARIATES IN COX PROPORTIONAL HAZARDS MODEL. [Masters Thesis]. University of Guelph; 2011. Available from: https://atrium.lib.uoguelph.ca/xmlui/handle/10214/2974

Vanderbilt University
6.
Kidd, Daniel Wayne.
Accelerated Time Propagation in Time-Dependent Density Functional Theory.
Degree: PhD, Physics, 2018, Vanderbilt University
URL: http://hdl.handle.net/1803/11656
► Time-dependent density functional theory (TDDFT) is a widely used, formally exact approach for describing quantum many-body electron dynamics. This approach makes possible the theoretical investigation…
(more)
▼ Time-dependent
density functional theory (TDDFT) is a widely used, formally exact approach for describing quantum many-body electron dynamics. This approach makes possible the theoretical investigation of laser-driven phenomenon occurring at the attosecond
time scale and angstrom length scale, of interest in a wide range of fields including many subdisciplines of physics, optics, biology, material engineering, chemistry, and computer engineering. The increased sophistication in speed and accuracy of this computational method allows for the enhanced reliability, applicability, and accessibility of quantum dynamics simulation programs. In order to further advance these aspects of the computational implementation of TDDFT, various means of accelerating such programs have been investigated. First, a class of basis set representations which is growing in popularity for such applications due to enhanced accuracy, the pseudospectral bases, was tested. It was shown that by modifying an exemplary sinc basis with sum-acceleration weights, the pseudospectral accuracy is maintained while allowing the computational efficiency to match that of other conventional methods. Next, various
time propagation techniques were applied to the description of electron dynamics in a one-dimensional Helium atom which had either been initialized in an excited state or
subject to driving laser fields. It was learned that a class of
time propagation techniques new to TDDFT, exponential integrator methods, outperform popular approaches due to their ability to well-represent the nonlinear terms in the relevant differential equations. Lastly, a new
time-dependent basis set comprised of Volkov states was introduced to the TDDFT description of periodic systems
subject to intense laser pulses. It was demonstrated that this basis is capable of allowing
time step sizes of up to an order of magnitude larger than those available in conventional techniques, thus allowing a similar speed up in simulation runtimes. This new basis was employed in investigative simulations of a periodic jellium model meant to describe the electronic rectification effect of recently suggested nano-scale diode devices.
Advisors/Committee Members: Neepa Maitra (committee member), Andreas Berlind (committee member), Sait Umar (committee member), Robert Scherrer (committee member), Kalman Varga (Committee Chair).
Subjects/Keywords: Density Functional Theory; simulation; basis functions; Time-Dependent Density Functional Theory; exponential integrator; pseudospectral
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Kidd, D. W. (2018). Accelerated Time Propagation in Time-Dependent Density Functional Theory. (Doctoral Dissertation). Vanderbilt University. Retrieved from http://hdl.handle.net/1803/11656
Chicago Manual of Style (16th Edition):
Kidd, Daniel Wayne. “Accelerated Time Propagation in Time-Dependent Density Functional Theory.” 2018. Doctoral Dissertation, Vanderbilt University. Accessed March 01, 2021.
http://hdl.handle.net/1803/11656.
MLA Handbook (7th Edition):
Kidd, Daniel Wayne. “Accelerated Time Propagation in Time-Dependent Density Functional Theory.” 2018. Web. 01 Mar 2021.
Vancouver:
Kidd DW. Accelerated Time Propagation in Time-Dependent Density Functional Theory. [Internet] [Doctoral dissertation]. Vanderbilt University; 2018. [cited 2021 Mar 01].
Available from: http://hdl.handle.net/1803/11656.
Council of Science Editors:
Kidd DW. Accelerated Time Propagation in Time-Dependent Density Functional Theory. [Doctoral Dissertation]. Vanderbilt University; 2018. Available from: http://hdl.handle.net/1803/11656

Brno University of Technology
7.
Smetana, Bedřich.
Algebraizace a parametrizace přechodových relací mezi strukturovanými objekty s aplikacemi v oblasti neuronových sítí: Algebraization and Parameterization Transition Relations between Structured Objects with Applications in the Field of Neural Networks.
Degree: 2020, Brno University of Technology
URL: http://hdl.handle.net/11012/195759
► The dissertation thesis investigates the modeling of the neural network activity with a focus on a multilayer forward neural network (MLP – Multi Layer Perceptron).…
(more)
▼ The dissertation thesis investigates the modeling of the neural network activity with a focus on a multilayer forward neural network (MLP – Multi Layer Perceptron). In this often used structure of neural networks,
time-
varying neurons are used, along with an analogy in modeling hyperstructures of linear differential operators. Using a finite lemma and defined hyperoperation, a hyperstructure composed of neurons is defined for a given transient function. There are examined their properties with an emphasis on structures with a layout.
Advisors/Committee Members: Chvalina, Jan (advisor), Beránek, Jaroslav (referee), Mayerová,, Šárka (referee).
Subjects/Keywords: Struktura a funkce dopředné neuronové sítě; Matematický model neuronové sítě; Časově proměnné neurony; Struktury lineárních diferenciálních operátorů; Analogie struktur časově proměnných neuronů; Teorie hyperstruktur a automatů; Modelovací funkce; Spojnicový prostor.; Structure and function of feed-forward neural network; Mathematical model of neural network; Time-varying neurons; Structures of linear differential operators; Analogy of structures of time-varying neurons; Theory of hyperstructures and automata; Modeling functions; Join space.
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Smetana, B. (2020). Algebraizace a parametrizace přechodových relací mezi strukturovanými objekty s aplikacemi v oblasti neuronových sítí: Algebraization and Parameterization Transition Relations between Structured Objects with Applications in the Field of Neural Networks. (Thesis). Brno University of Technology. Retrieved from http://hdl.handle.net/11012/195759
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Smetana, Bedřich. “Algebraizace a parametrizace přechodových relací mezi strukturovanými objekty s aplikacemi v oblasti neuronových sítí: Algebraization and Parameterization Transition Relations between Structured Objects with Applications in the Field of Neural Networks.” 2020. Thesis, Brno University of Technology. Accessed March 01, 2021.
http://hdl.handle.net/11012/195759.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Smetana, Bedřich. “Algebraizace a parametrizace přechodových relací mezi strukturovanými objekty s aplikacemi v oblasti neuronových sítí: Algebraization and Parameterization Transition Relations between Structured Objects with Applications in the Field of Neural Networks.” 2020. Web. 01 Mar 2021.
Vancouver:
Smetana B. Algebraizace a parametrizace přechodových relací mezi strukturovanými objekty s aplikacemi v oblasti neuronových sítí: Algebraization and Parameterization Transition Relations between Structured Objects with Applications in the Field of Neural Networks. [Internet] [Thesis]. Brno University of Technology; 2020. [cited 2021 Mar 01].
Available from: http://hdl.handle.net/11012/195759.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Smetana B. Algebraizace a parametrizace přechodových relací mezi strukturovanými objekty s aplikacemi v oblasti neuronových sítí: Algebraization and Parameterization Transition Relations between Structured Objects with Applications in the Field of Neural Networks. [Thesis]. Brno University of Technology; 2020. Available from: http://hdl.handle.net/11012/195759
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

NSYSU
8.
Hsu, Lee-Yang.
Dynamic Economic Dispatch Incorporating Renewable Energy with Carbon Trading.
Degree: Master, Electrical Engineering, 2012, NSYSU
URL: http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0619112-174014
► Carbon dioxide (CO2) is the most important component of Greenhouse Gas (GHG) that causes global warming and sea-level rising. Thermal power plants dominate electric power…
(more)
▼ Carbon dioxide (CO2) is the most important component of Greenhouse Gas (GHG) that causes global warming and sea-level rising. Thermal power plants dominate electric power generation in the world, and has been reported to be the major contributor of CO2 emission. To prevent the related global warming caused by GHG emission, carbon quota trading is implemented and becomes a gradually arising market. This thesis proposed a research focused on the relationship between the carbon trading scheme and dynamic economic dispatch (DED) problem for the public utility. A model of the carbon trading market was investigated and introduced into DED problem incorporating wind and solar power plant.
A refined particle swarm optimization (PSO) algorithm, PSO with
time-
varying acceleration coefficients (PSO-TVAC), is applied to determine the DED strategy with the incorporation of independent power providers (IPPs) and green power plant. The model of the carbon trading was considered in the DED problem. Carbon reduction is treated as the inner-cost of utility, and the fictitious carbon quotas can be resold to the market, while the energy shortage can be satisfied by purchasing quotas from the market. In order to avoid premature convergence of the original PSO, the PSO-TVAC method is introduced to improve the searching efficiency.
Advisors/Committee Members: Ta-peng Tsao (chair), Whei-Min Lin (committee member), Fu-Sheng Zheng (chair), Dong-Sheng Zhan (chair).
Subjects/Keywords: Particle Swarm Optimization with Time-Varying Acceleration Coefficients; Weibull Probability Density Function; Dynamic Economic Dispatch; Carbon Trading.; CO2 Emission
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Hsu, L. (2012). Dynamic Economic Dispatch Incorporating Renewable Energy with Carbon Trading. (Thesis). NSYSU. Retrieved from http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0619112-174014
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Hsu, Lee-Yang. “Dynamic Economic Dispatch Incorporating Renewable Energy with Carbon Trading.” 2012. Thesis, NSYSU. Accessed March 01, 2021.
http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0619112-174014.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Hsu, Lee-Yang. “Dynamic Economic Dispatch Incorporating Renewable Energy with Carbon Trading.” 2012. Web. 01 Mar 2021.
Vancouver:
Hsu L. Dynamic Economic Dispatch Incorporating Renewable Energy with Carbon Trading. [Internet] [Thesis]. NSYSU; 2012. [cited 2021 Mar 01].
Available from: http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0619112-174014.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Hsu L. Dynamic Economic Dispatch Incorporating Renewable Energy with Carbon Trading. [Thesis]. NSYSU; 2012. Available from: http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0619112-174014
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Texas A&M University
9.
Ma, Guangyi.
Three Essays on Estimation and Testing of Nonparametric Models.
Degree: PhD, Economics, 2012, Texas A&M University
URL: http://hdl.handle.net/1969.1/ETD-TAMU-2012-08-11768
► In this dissertation, I focus on the development and application of nonparametric methods in econometrics. First, a constrained nonparametric regression method is developed to estimate…
(more)
▼ In this dissertation, I focus on the development and application of nonparametric methods in econometrics. First, a constrained nonparametric regression method is developed to estimate a function and its derivatives
subject to shape restrictions implied by economic theory. The constrained estimators can be viewed as a set of empirical likelihood-based reweighted local polynomial estimators. They are shown to be weakly consistent and have the same first order asymptotic distribution as the unconstrained estimators. When the shape restrictions are correctly specified, the constrained estimators can achieve a large degree of finite sample bias reduction and thus outperform the unconstrained estimators. The constrained nonparametric regression method is applied on the estimation of daily option pricing function and state-price
density function.
Second, a modified Cumulative Sum of Squares (CUSQ) test is proposed to test structural changes in the unconditional volatility in a
time-
varying coefficient model. The proposed test is based on nonparametric residuals from local linear estimation of the
time-
varying coefficients. Asymptotic theory is provided to show that the new CUSQ test has standard null distribution and diverges at standard rate under the alternatives. Compared with a test based on least squares residuals, the new test enjoys correct size and good power properties. This is because, by estimating the model nonparametrically, one can circumvent the size distortion from potential structural changes in the mean. Empirical results from both simulation experiments and real data applications are presented to demonstrate the test's size and power properties.
Third, an empirical study of testing the Purchasing Power Parity (PPP) hypothesis is conducted in a functional-coefficient cointegration model, which is consistent with equilibrium models of exchange rate determination with the presence of trans- actions costs in international trade. Supporting evidence of PPP is found in the recent float exchange rate era. The cointegration relation of nominal exchange rate and price levels varies conditioning on the real exchange rate volatility. The cointegration coefficients are more stable and numerically near the value implied by PPP theory when the real exchange rate volatility is relatively lower.
Advisors/Committee Members: Xu, Ke-Li (advisor), Li, Qi (committee member), Jansen, Dennis W. (committee member), Kim, Hwagyun (committee member).
Subjects/Keywords: Constrained nonparametric regression; CUSUM of squares test; derivative estimation; empirical likelihood; functional-coefficient cointegration; nonparametric alternative; option pricing; purchasing power parity; state-price density; structural change; time-varying coefficient model; volatility break.
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Ma, G. (2012). Three Essays on Estimation and Testing of Nonparametric Models. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2012-08-11768
Chicago Manual of Style (16th Edition):
Ma, Guangyi. “Three Essays on Estimation and Testing of Nonparametric Models.” 2012. Doctoral Dissertation, Texas A&M University. Accessed March 01, 2021.
http://hdl.handle.net/1969.1/ETD-TAMU-2012-08-11768.
MLA Handbook (7th Edition):
Ma, Guangyi. “Three Essays on Estimation and Testing of Nonparametric Models.” 2012. Web. 01 Mar 2021.
Vancouver:
Ma G. Three Essays on Estimation and Testing of Nonparametric Models. [Internet] [Doctoral dissertation]. Texas A&M University; 2012. [cited 2021 Mar 01].
Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2012-08-11768.
Council of Science Editors:
Ma G. Three Essays on Estimation and Testing of Nonparametric Models. [Doctoral Dissertation]. Texas A&M University; 2012. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2012-08-11768

Virginia Tech
10.
Thorson, James Turner.
Multi-Species Models of Time-Varying Catchability in the U.S. Gulf of Mexico.
Degree: MS, Fisheries and Wildlife Sciences, 2009, Virginia Tech
URL: http://hdl.handle.net/10919/32662
► The catchability coefficient is used in most marine stock assessment models, and is usually assumed to be stationary and density-independent. However, recent research has shown…
(more)
▼ The catchability coefficient is used in most marine stock assessment models, and is usually assumed to be stationary and
density-independent. However, recent research has shown that these assumptions are violated in most fisheries. Violation of these assumptions will cause underestimation of stock declines or recoveries, leading to inappropriate management policies. This project assesses the soundness of stationarity and
density independence assumptions using multi-species data for seven stocks and four gears in the U.S. Gulf of Mexico. This study also develops a multi-species methodology to compensate for failures of either assumption.
To evaluate catchability assumptions, abundance-at-age was reconstructed and compared with catch-per-unit-effort data in the Gulf. Mixed-effects, Monte Carlo, and bootstrap analyses were applied to estimate
time-
varying catchability parameters. Gulf data showed large and significant
density dependence (0.71, s.e. 0.07, p<0.001) and increasing trends in catchability (2.0% annually compounding, s.e. 0.6%, p < 0.001).
Simulation modeling was also used to evaluate the accuracy and precision of seven different single-species and multi-species estimation procedures. Imputing estimates from similar species provided accurate estimates of catchability parameters. Multi-species estimates also improved catchability estimation when compared with the current assumptions of
density independence and stationarity.
This study shows that multi-species data in the Gulf of Mexico have sufficient quantity and quality to accurately estimate catchability model parameters. This study also emphasizes the importance of estimating
density-dependent and
density-independent factors simultaneously. Finally, this study shows that multi-species imputation of catchability estimates decreases errors compared with current assumptions, when applied to single-species stock assessment data.
Advisors/Committee Members: Berkson, James M. (committeechair), Murphy, Brian R. (committee member), Porch, Clay (committee member), Orth, Donald J. (committee member).
Subjects/Keywords: Gulf of Mexico; snapper/grouper fisheries; stock assessment; simulation model; time-varying catchability; density dependence; technology creep; multi-species
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Thorson, J. T. (2009). Multi-Species Models of Time-Varying Catchability in the U.S. Gulf of Mexico. (Masters Thesis). Virginia Tech. Retrieved from http://hdl.handle.net/10919/32662
Chicago Manual of Style (16th Edition):
Thorson, James Turner. “Multi-Species Models of Time-Varying Catchability in the U.S. Gulf of Mexico.” 2009. Masters Thesis, Virginia Tech. Accessed March 01, 2021.
http://hdl.handle.net/10919/32662.
MLA Handbook (7th Edition):
Thorson, James Turner. “Multi-Species Models of Time-Varying Catchability in the U.S. Gulf of Mexico.” 2009. Web. 01 Mar 2021.
Vancouver:
Thorson JT. Multi-Species Models of Time-Varying Catchability in the U.S. Gulf of Mexico. [Internet] [Masters thesis]. Virginia Tech; 2009. [cited 2021 Mar 01].
Available from: http://hdl.handle.net/10919/32662.
Council of Science Editors:
Thorson JT. Multi-Species Models of Time-Varying Catchability in the U.S. Gulf of Mexico. [Masters Thesis]. Virginia Tech; 2009. Available from: http://hdl.handle.net/10919/32662

Penn State University
11.
Yang, Songshan.
TIME-VARYING EFFECT MODEL FOR STUDYING GROUP DIFFERENCE IN HEALTH BEHAVIOR.
Degree: 2018, Penn State University
URL: https://submit-etda.libraries.psu.edu/catalog/14792szy125
► The thesis includes two projects related to the detection of group difference of health risk behavior using time-varying effect models. In the first project, we…
(more)
▼ The thesis includes two projects related to the detection of group difference of health risk behavior using
time-
varying effect models. In the first project, we proposed to use a
time-
varying effect model to characterize
gender-specific trajectories of health behaviors, and we also conducted hypothesis testing for gender differences. We first used two motivating examples which demonstrated that the proposed model works for both the longitudinal studies and the short-term studies that involve intensive data collection. Then
a simulation study is conducted, which shows that the accuracy of estimation of trajectory
functions improves as the sample size and the number of
time points increase. In terms of the performance of the hypothesis testing, the type I error rates are close to their corresponding significance levels under all combinations of
sample size and number of
time points. In addition, the power increases as the alternative hypothesis deviates more from the null hypothesis, and the rate of this increasing trend is higher when the sample size and the number of
time points are larger.
The second project proposed to use a
time-
varying effect model for examining group differences in trajectories of zero-inflated count outcomes. The motivating example demonstrates that this zero-inflated Poisson model allows investigators to study group differences in different aspects of substance use (e.g. the probability
of abstinence and the quantity of alcohol use) simultaneously. The simulation study shows that the accuracy of estimation of trajectory
functions improves as the sample size increases; the accuracy under equal group sizes is only higher when the sample size is small (100). By examining the performance of the hypothesis testing,
we found that the type I error rates are close to their corresponding significance levels under all settings. On the other hand, the power also increases as the alternative hypothesis deviates more from the null hypothesis and the rate of this increasing trend is higher when the sample size is larger. Moreover, the hypothesis test for the group difference in the zero component tends to be less powerful than the test for the group difference in the Poisson component.
Advisors/Committee Members: Runze Li, Thesis Advisor/Co-Advisor, Bing Li, Committee Member, Matthew Logan Reimherr, Committee Member.
Subjects/Keywords: Time varying-coefficient effect model
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Yang, S. (2018). TIME-VARYING EFFECT MODEL FOR STUDYING GROUP DIFFERENCE IN HEALTH BEHAVIOR. (Thesis). Penn State University. Retrieved from https://submit-etda.libraries.psu.edu/catalog/14792szy125
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Yang, Songshan. “TIME-VARYING EFFECT MODEL FOR STUDYING GROUP DIFFERENCE IN HEALTH BEHAVIOR.” 2018. Thesis, Penn State University. Accessed March 01, 2021.
https://submit-etda.libraries.psu.edu/catalog/14792szy125.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Yang, Songshan. “TIME-VARYING EFFECT MODEL FOR STUDYING GROUP DIFFERENCE IN HEALTH BEHAVIOR.” 2018. Web. 01 Mar 2021.
Vancouver:
Yang S. TIME-VARYING EFFECT MODEL FOR STUDYING GROUP DIFFERENCE IN HEALTH BEHAVIOR. [Internet] [Thesis]. Penn State University; 2018. [cited 2021 Mar 01].
Available from: https://submit-etda.libraries.psu.edu/catalog/14792szy125.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Yang S. TIME-VARYING EFFECT MODEL FOR STUDYING GROUP DIFFERENCE IN HEALTH BEHAVIOR. [Thesis]. Penn State University; 2018. Available from: https://submit-etda.libraries.psu.edu/catalog/14792szy125
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Ottawa
12.
Yan, Kai.
Opinion Dynamics and the Effect of Time-varying Opinions: A Simulation Study
.
Degree: 2015, University of Ottawa
URL: http://hdl.handle.net/10393/32959
► Opinion dynamics is extensively used in studying large-scale social, economical, political and natural phenomena that involve many interacting agents. It also can be used to…
(more)
▼ Opinion dynamics is extensively used in studying large-scale social, economical, political and natural phenomena that involve many interacting agents. It also can be used to model the evolution of teams of autonomous vehicles operating in a coordinated fashion with civilian and military applications, when arbitration among individual goals needs to be negotiated. Recently, research was conducted on how opinion dynamics can be the core of collective decision-making mechanisms for swarm robotics. Opinion dynamics with a time varying opinion space, which is the set of all possible opinions an agent may have, is a relatively recent research topic.
In this work, the Deffuant-Weisbuch model (DW model), which allows to model opinion dynamics in shrinking opinion spaces, was applied. In simulating this class of systems and in extracting information from them it is crucial to establish reliable algorithms and criteria for counting the numbers of clusters, as this ultimately affects the determination of the steady state of the system. A method was applied to combine Fuzzy c-means clustering and subtractive clustering to check convergence of the system and avoid negative influence of outliers. Different scenarios are simulated to study the influence of characteristic parameters on the formation of opinions, which is quantified by the formation of clusters in the opinion space. Additionally, we simulate the scenario of a two dimensional opinion space in which one side shrinks, and evaluate how the rate of shrinking influences the steady state opinion space. This is a simplified model to gain some insight on the effect of extreme changes of opinions in multi-dimensional opinion space.
Subjects/Keywords: Opinion dynamics;
Time-varying
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Yan, K. (2015). Opinion Dynamics and the Effect of Time-varying Opinions: A Simulation Study
. (Thesis). University of Ottawa. Retrieved from http://hdl.handle.net/10393/32959
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Yan, Kai. “Opinion Dynamics and the Effect of Time-varying Opinions: A Simulation Study
.” 2015. Thesis, University of Ottawa. Accessed March 01, 2021.
http://hdl.handle.net/10393/32959.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Yan, Kai. “Opinion Dynamics and the Effect of Time-varying Opinions: A Simulation Study
.” 2015. Web. 01 Mar 2021.
Vancouver:
Yan K. Opinion Dynamics and the Effect of Time-varying Opinions: A Simulation Study
. [Internet] [Thesis]. University of Ottawa; 2015. [cited 2021 Mar 01].
Available from: http://hdl.handle.net/10393/32959.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Yan K. Opinion Dynamics and the Effect of Time-varying Opinions: A Simulation Study
. [Thesis]. University of Ottawa; 2015. Available from: http://hdl.handle.net/10393/32959
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Virginia Tech
13.
Magruder, Caleb Clarke III.
Model Reduction of Linear Time-Periodic Dynamical Systems.
Degree: MS, Mathematics, 2013, Virginia Tech
URL: http://hdl.handle.net/10919/23112
► Few model reduction techniques exist for dynamical systems whose parameters vary with time. We have particular interest here in linear time-periodic dynamical systems; we seek…
(more)
▼ Few model reduction techniques exist for dynamical systems whose parameters vary with
time. We have particular interest here in linear
time-periodic dynamical systems; we seek a structure-preserving algorithm for model reduction of linear
time-periodic (LTP) dynamical systems of large scale that generalizes from the linear
time-invariant (LTI) model reduction problem. We extend the familiar LTI system theory to analogous concepts in the LTP setting. First, we represent the LTP system as a convolution operator of a bivariate periodic kernel function. The kernel suggests a representation of the system as a frequency operator, called the Harmonic Transfer Function. Second, we exploit the Hilbert space structure of the family of LTP systems to develop necessary conditions for optimal approximations. Additionally, we show an a posteriori error bound written in terms of the \\mathcal H
2 norm of related LTI multiple input/multiple output system. This bound inspires an algorithm to construct approximations of reduced order. To verify the efficacy of this algorithm we apply it to three models: (1) fluid flow around a cylinder by a finite element discretization of the Navier-Stokes equations, (2) thermal diffusion through a plate modeled by the heat equation, and (3) structural model of component 1r of the Russian service module of the International Space Station.
Advisors/Committee Members: Gugercin, Serkan (committeechair), Rossi, John F. (committee member), Beattie, Christopher A. (committee member).
Subjects/Keywords: Model Reduction; Time-varying Systems
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Magruder, C. C. I. (2013). Model Reduction of Linear Time-Periodic Dynamical Systems. (Masters Thesis). Virginia Tech. Retrieved from http://hdl.handle.net/10919/23112
Chicago Manual of Style (16th Edition):
Magruder, Caleb Clarke III. “Model Reduction of Linear Time-Periodic Dynamical Systems.” 2013. Masters Thesis, Virginia Tech. Accessed March 01, 2021.
http://hdl.handle.net/10919/23112.
MLA Handbook (7th Edition):
Magruder, Caleb Clarke III. “Model Reduction of Linear Time-Periodic Dynamical Systems.” 2013. Web. 01 Mar 2021.
Vancouver:
Magruder CCI. Model Reduction of Linear Time-Periodic Dynamical Systems. [Internet] [Masters thesis]. Virginia Tech; 2013. [cited 2021 Mar 01].
Available from: http://hdl.handle.net/10919/23112.
Council of Science Editors:
Magruder CCI. Model Reduction of Linear Time-Periodic Dynamical Systems. [Masters Thesis]. Virginia Tech; 2013. Available from: http://hdl.handle.net/10919/23112

University of Notre Dame
14.
Rachel Baird.
The Effect of Misspecifying Random-Effect Time-Varying
Predictors as Fixed on Estimates of Other
Parameters</h1>.
Degree: Psychology, 2016, University of Notre Dame
URL: https://curate.nd.edu/show/p5547p90t1d
► Time-varying predictors in multilevel models are a useful tool for longitudinal research, whether they are the research variable of interest or they are controlling…
(more)
▼ Time-
varying predictors in multilevel models
are a useful tool for longitudinal research, whether they are the
research variable of interest or they are controlling for variance
to allow greater power for other variables. However, standard
recommendations to fix the effect of
time-
varying predictors may
make an assumption that is unlikely to hold in reality and may
influence results. This dissertation illustrates that treating the
time-
varying predictor as fixed may allow analyses to converge, but
the analyses have poor
coverage of the true fixed effect when the
time-
varying predictor has a random effect in reality. A second
simulation study shows that treating the
time-
varying predictor as
random may have poor convergence, except when allowing negative
variance estimates. Although negative variance estimates are
uninterpretable, results of the simulation show that estimates of
the fixed effect of the
time-
varying predictor are as accurate for
these cases as for cases with positive variance estimates, and that
treating the
time-
varying predictor as random and allowing negative
variance estimates performs well whether the
time-
varying predictor
is fixed or random in reality. Because of the difficulty of
interpreting negative variance estimates, two procedures are
suggested for selection between fixed-effect and random-effect
models: comparing between fixed-effect and constrained
random-effect models with a likelihood ratio test or fitting a
fixed-effect model when an unconstrained random-effect model
produces negative variance estimates. The performance of these two
procedures is
compared.
Advisors/Committee Members: Scott Maxwell, Research Director.
Subjects/Keywords: multilevel; time-varying predictor; time-varying covariate; longitudinal
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Baird, R. (2016). The Effect of Misspecifying Random-Effect Time-Varying
Predictors as Fixed on Estimates of Other
Parameters</h1>. (Thesis). University of Notre Dame. Retrieved from https://curate.nd.edu/show/p5547p90t1d
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Baird, Rachel. “The Effect of Misspecifying Random-Effect Time-Varying
Predictors as Fixed on Estimates of Other
Parameters</h1>.” 2016. Thesis, University of Notre Dame. Accessed March 01, 2021.
https://curate.nd.edu/show/p5547p90t1d.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Baird, Rachel. “The Effect of Misspecifying Random-Effect Time-Varying
Predictors as Fixed on Estimates of Other
Parameters</h1>.” 2016. Web. 01 Mar 2021.
Vancouver:
Baird R. The Effect of Misspecifying Random-Effect Time-Varying
Predictors as Fixed on Estimates of Other
Parameters</h1>. [Internet] [Thesis]. University of Notre Dame; 2016. [cited 2021 Mar 01].
Available from: https://curate.nd.edu/show/p5547p90t1d.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Baird R. The Effect of Misspecifying Random-Effect Time-Varying
Predictors as Fixed on Estimates of Other
Parameters</h1>. [Thesis]. University of Notre Dame; 2016. Available from: https://curate.nd.edu/show/p5547p90t1d
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Western Ontario
15.
Cui, Xizhong.
New Model And Simulation Algorithm Of Nonstationary Non-gaussian Ground Motions Based On S-transform.
Degree: 2020, University of Western Ontario
URL: https://ir.lib.uwo.ca/etd/7221
► The seismic ground motions are nonstationary stochastic processes and vary from site to site. The time histories of synthetic ground motions are used for nonlinear…
(more)
▼ The seismic ground motions are nonstationary stochastic processes and vary from site to site. The time histories of synthetic ground motions are used for nonlinear inelastic structural dynamic analysis since the historical records are limit or unavailable for a particular scenario seismic event. This is especially the case for structures with multiple supports. The characteristics of the nonstationary stochastic ground motions depend on the earthquake magnitude, fault mechanism, source-to-site distance, and local site conditions. The characteristics could be represented by time-frequency (dependent) power spectral density (TFPSD) and coherence functions. The assessment of such power spectral density and coherence functions are presented by using historical records and the S-transform – a Fourier transform with time localized and frequency-dependent windows – is carried out. New models of the TFPSD function and coherence function are presented. Also, new time-frequency spectral representation methods (TFSRMs) to simulate nonstationary stochastic processes are proposed. The TFSRM is developed by taking the advantages of the orthonormal basis functions in the discrete orthogonal S-transform (DOST) and the refined time-frequency representation obtained by using the S-transform. TFSRM can be used to simulate ground motions at a single site or multiple sites. They can also be used to simulate seismic ground motions conditioned on observed ground motions. TFSRM can cope with the time-varying lagged coherence function; this is not the case with the well-known spectral representation method (SRM).
Similar to the SRM, the direct use of TFSRM leads to Gaussian processes (stationary or nonstationary). However, there is indicates that the seismic ground motions may not be Gaussian. A new iterative power and amplitude correction algorithm is proposed to simulate nonstationary non-Gaussian stochastic processes. This procedure is successfully implemented and illustrated by numerical examples.
Subjects/Keywords: earthquake ground motion; spatial-varying; S-transform; discrete orthonormal S-transform; simulation; time-dependent coherence; time-dependent power spectral density function; Structural Engineering
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Cui, X. (2020). New Model And Simulation Algorithm Of Nonstationary Non-gaussian Ground Motions Based On S-transform. (Thesis). University of Western Ontario. Retrieved from https://ir.lib.uwo.ca/etd/7221
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Cui, Xizhong. “New Model And Simulation Algorithm Of Nonstationary Non-gaussian Ground Motions Based On S-transform.” 2020. Thesis, University of Western Ontario. Accessed March 01, 2021.
https://ir.lib.uwo.ca/etd/7221.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Cui, Xizhong. “New Model And Simulation Algorithm Of Nonstationary Non-gaussian Ground Motions Based On S-transform.” 2020. Web. 01 Mar 2021.
Vancouver:
Cui X. New Model And Simulation Algorithm Of Nonstationary Non-gaussian Ground Motions Based On S-transform. [Internet] [Thesis]. University of Western Ontario; 2020. [cited 2021 Mar 01].
Available from: https://ir.lib.uwo.ca/etd/7221.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Cui X. New Model And Simulation Algorithm Of Nonstationary Non-gaussian Ground Motions Based On S-transform. [Thesis]. University of Western Ontario; 2020. Available from: https://ir.lib.uwo.ca/etd/7221
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Florida
16.
Sorley, Stephen.
Identification and Analysis of Time-Varying Modal Parameters.
Degree: MS, Mechanical Engineering - Mechanical and Aerospace Engineering, 2010, University of Florida
URL: https://ufdc.ufl.edu/UFE0042601
► In this thesis, methods for identifying and analyzing the modal parameters of a linear, time-varying system with no control input are proposed. These methods are…
(more)
▼ In this thesis, methods for identifying and analyzing the modal parameters of a linear,
time-
varying system with no control input are proposed. These methods are derived from two related definitions for
time-
varying poles and eigenvectors found in the literature. The limitations of the analysis methods used for each
time-
varying eigenpair definition are explored. Practical requirements regarding the quantity and quality of the experimental data used in each identification method are also addressed. Finally, a morphing-wing aircraft model is analyzed using the proposed techniques, and the results are compared to traditional frozen-
time analysis for a particular morphing trajectory. ( en )
Advisors/Committee Members: Lind, Richard C. (committee chair), Ranka, Sanjay (committee member).
Subjects/Keywords: Aircraft; Cost functions; Eigenvectors; Labor theories of value; Mathematical vectors; Matrices; Modal response; Scalars; State vectors; Trajectories; aircraft, control, eigenvalue, identification, kamen, mode, morphing, pole, time, varying
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Sorley, S. (2010). Identification and Analysis of Time-Varying Modal Parameters. (Masters Thesis). University of Florida. Retrieved from https://ufdc.ufl.edu/UFE0042601
Chicago Manual of Style (16th Edition):
Sorley, Stephen. “Identification and Analysis of Time-Varying Modal Parameters.” 2010. Masters Thesis, University of Florida. Accessed March 01, 2021.
https://ufdc.ufl.edu/UFE0042601.
MLA Handbook (7th Edition):
Sorley, Stephen. “Identification and Analysis of Time-Varying Modal Parameters.” 2010. Web. 01 Mar 2021.
Vancouver:
Sorley S. Identification and Analysis of Time-Varying Modal Parameters. [Internet] [Masters thesis]. University of Florida; 2010. [cited 2021 Mar 01].
Available from: https://ufdc.ufl.edu/UFE0042601.
Council of Science Editors:
Sorley S. Identification and Analysis of Time-Varying Modal Parameters. [Masters Thesis]. University of Florida; 2010. Available from: https://ufdc.ufl.edu/UFE0042601

Universidade Estadual de Campinas
17.
Lacerda, Márcio Júnior, 1987-.
Contribuições ao problema de filtragem H-infinito para sistemas dinâmicos: Contributions to the H-infinity problem for dynamical systems.
Degree: 2014, Universidade Estadual de Campinas
URL: http://repositorio.unicamp.br/jspui/handle/REPOSIP/261059
► Abstract: This work presents new conditions in the form of linear matrix inequalities for full order H-infinity filter design in three different contexts: i) uncertain…
(more)
▼ Abstract: This work presents new conditions in the form of linear matrix inequalities for full order H-infinity filter design in three different contexts: i) uncertain linear discrete-
time systems with a
time-
varying delay affecting the states ii) linear parameter-
varying systems, continuous and discrete-
time,
subject to inexactly measured parameters; iii) continuous and discrete-
time nonlinear quadratic systems. For each context, the aim is to design filters: i) with state-delayed terms; ii) dependent upon the inexactly measured parameters; iii) with quadratic terms. In each case, the starting point is the existence of a Lyapunov function that assures stability and a bound to the H-infinity norm of the augmented system, that is, the original system conected with the full order filter. The design conditions are obtained by imposing a given structure to the slack variables, resulting in matrix inequalities with scalar parameters. The effectiveness of the proposed conditions is illustrated by means of numerical comparisons and benchmark examples from the literature
Advisors/Committee Members: UNIVERSIDADE ESTADUAL DE CAMPINAS (CRUESP), Peres, Pedro Luis Dias, 1960- (advisor), Oliveira, Ricardo Coração de Leão Fontoura de, 1978- (coadvisor), Universidade Estadual de Campinas. Faculdade de Engenharia Elétrica e de Computação (institution), Programa de Pós-Graduação em Engenharia Elétrica (nameofprogram), Dorea, Carlos Eduardo Trabuco (committee member), Neto, Eugenio de Bona Castelan (committee member), Val, João Bosco Ribeiro do (committee member), Santos, Juan Francisco Camino dos (committee member).
Subjects/Keywords: Teoria de controle; Sistemas lineares variantes no tempo; Sistemas não-lineares; Lyapunov, Funções de; Estabilidade; Control theory; Linear time-varying systems; Nonlinear systems; Lyapunov functions; Stability
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Lacerda, Márcio Júnior, 1. (2014). Contribuições ao problema de filtragem H-infinito para sistemas dinâmicos: Contributions to the H-infinity problem for dynamical systems. (Thesis). Universidade Estadual de Campinas. Retrieved from http://repositorio.unicamp.br/jspui/handle/REPOSIP/261059
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Lacerda, Márcio Júnior, 1987-. “Contribuições ao problema de filtragem H-infinito para sistemas dinâmicos: Contributions to the H-infinity problem for dynamical systems.” 2014. Thesis, Universidade Estadual de Campinas. Accessed March 01, 2021.
http://repositorio.unicamp.br/jspui/handle/REPOSIP/261059.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Lacerda, Márcio Júnior, 1987-. “Contribuições ao problema de filtragem H-infinito para sistemas dinâmicos: Contributions to the H-infinity problem for dynamical systems.” 2014. Web. 01 Mar 2021.
Vancouver:
Lacerda, Márcio Júnior 1. Contribuições ao problema de filtragem H-infinito para sistemas dinâmicos: Contributions to the H-infinity problem for dynamical systems. [Internet] [Thesis]. Universidade Estadual de Campinas; 2014. [cited 2021 Mar 01].
Available from: http://repositorio.unicamp.br/jspui/handle/REPOSIP/261059.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Lacerda, Márcio Júnior 1. Contribuições ao problema de filtragem H-infinito para sistemas dinâmicos: Contributions to the H-infinity problem for dynamical systems. [Thesis]. Universidade Estadual de Campinas; 2014. Available from: http://repositorio.unicamp.br/jspui/handle/REPOSIP/261059
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Australian National University
18.
Phan, Tuan Anh.
Empirical Essays on Monetary Policy and Transmission
.
Degree: 2014, Australian National University
URL: http://hdl.handle.net/1885/144593
► This thesis presents four self-contained empirical research papers on monetary policy and monetary transmission using vector autoregression (VAR), structural VAR (SVAR), and Bayesian time-varying parameter…
(more)
▼ This thesis presents four self-contained empirical research
papers on monetary policy and monetary transmission using vector
autoregression (VAR), structural VAR (SVAR), and Bayesian
time-varying parameter VAR (TVP-VAR) models. The first two papers
compare aspects of monetary policy and transmission in selected
developed countries: Australia, the US, and the Euro area
(Chapter 3); and Australia, the US, UK, and Canada (Chapter 4).
The last two papers (Chapters 5 and 6) explore monetary policy
and effects of monetary policy on inflation in Vietnam – a
transition developing country.
The empirical results indicate that the investment channel of
monetary policy transmission plays a more important role than the
consumption channel in Australia. Meanwhile the investment
channel and the consumption channel make similar contributions to
the overall transmission of monetary policy in the Euro area and
the US. The difference between Australia and the Euro area
appears to come from differences in housing investment responses,
whereas Australia differs from the US mainly because it has a
lower share of household consumption in total demand.
Results from TVP-VAR models suggest that there were comovements
in the monetary policy reactions to unemployment across countries
before the recent Global Financial Crisis (GFC). The policy rate
seems to react more strongly to unemployment changes in more
recent years, especially in the US and UK. Monetary policy
responses to inflation/deflation are observed to be divided into
two groups, with the responses in the US and UK showing a
different pattern to the responses in Canada and Australia.
Monetary policy seems to react most aggressively against
inflation/deflation in the US. The effects of monetary policy
shocks on unemployment and inflation are similar across
countries, and seem to have weakened over time.
Results also suggest that monetary policy transmission to
inflation in a transition country like Vietnam appears to work in
a similar way to as in developed countries. The impulse response
functions of inflation to shocks in monetary policy are plausible
and robust across the VAR and SVAR models. The policy interest
rate plays an important role in affecting inflation. For the case
of Vietnam as a small, open economy, shocks to output and prices
in trading partners also appear to have strong effects on
domestic inflation.
Allowing for the time-varying nature of the parameters and
variance/covariance matrices, the results suggest that the State
Bank of Vietnam (SBV) appears to have been steadily using
monetary policy tools to contain inflation. TVP-VAR results also
confirm that monetary policy in Vietnam appears to lead to
reasonable inflation responses. The evidence therefore supports
the argument that Vietnam’s monetary policy might be more
effective than…
Subjects/Keywords: Monetary Policy;
Monetary Transmission;
Vector Autoregression;
Time-varying parameter VAR;
SVAR;
Determinants of Vietnam inflation;
output composition;
Australia
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Phan, T. A. (2014). Empirical Essays on Monetary Policy and Transmission
. (Thesis). Australian National University. Retrieved from http://hdl.handle.net/1885/144593
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Phan, Tuan Anh. “Empirical Essays on Monetary Policy and Transmission
.” 2014. Thesis, Australian National University. Accessed March 01, 2021.
http://hdl.handle.net/1885/144593.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Phan, Tuan Anh. “Empirical Essays on Monetary Policy and Transmission
.” 2014. Web. 01 Mar 2021.
Vancouver:
Phan TA. Empirical Essays on Monetary Policy and Transmission
. [Internet] [Thesis]. Australian National University; 2014. [cited 2021 Mar 01].
Available from: http://hdl.handle.net/1885/144593.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Phan TA. Empirical Essays on Monetary Policy and Transmission
. [Thesis]. Australian National University; 2014. Available from: http://hdl.handle.net/1885/144593
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Virginia Tech
19.
Onen, Ahmet.
Model-Based Grid Modernization Economic Evaluation Framework.
Degree: PhD, Electrical Engineering, 2014, Virginia Tech
URL: http://hdl.handle.net/10919/46981
► A smart grid cost/benefit analysis answers a series of economic questions that address the incremental benefits of each stage or decision point. Each stage of…
(more)
▼ A smart grid cost/benefit analysis answers a series of economic questions that address the incremental benefits of each stage or decision point. Each stage of the economic analysis provides information about the incremental benefits of that stage with respect to the previous stage. With this approach stages that provide little or no economic benefits can be identified. In this study there are series of applications,-including quasi-steady state power flows over
time-
varying loads and costs of service, Monte Carlo simulations, reconfiguration for restoration, and coordinated control - that are used to evaluate the cost-benefits of a series of smart grid investments.
In the electric power system planning process, engineers seek to identify the most cost-effective means of serving the load within reliability and power quality criteria. In order to accurately assess the cost of a given project, the feeder losses must be calculated. In the past, the feeder losses were estimated based upon the peak load and a calculated load factor for the year. The cost of these losses would then be calculated based upon an expected, fixed per-kWh generation cost. This dissertation presents a more accurate means of calculating the cost of losses, using hourly feeder load information and
time-
varying electric energy cost data. The work here attempts to quantify the improvement in high accuracy and presents an example where the economic evaluation of a planning project requires the more accurate loss calculation.
Smart grid investments can also affect response to equipment failures where there are two types of responses to consider -blue-sky day and storm. Storm response and power restoration can be very expensive for electric utilities. The deployment of automated switches can benefit the utility by decreasing storm restoration hours. The automated switches also improve system reliably by decreasing customer interruption duration. In this dissertation a Monte Carlo simulation is used to mimic storm equipment failure events, followed by reconfiguration for restoration and power flow evaluations. The Monte Carlo simulation is driven by actual storm statistics taken from 89 different storms, where equipment failure rates are
time varying. The customer outage status and durations are examined. Changes in reliability for the system with and without automated switching devices are investigated.
Time varying coordinated control of Conservation Voltage Reduction (CVR) is implemented. The coordinated control runs in the control center and makes use of measurements from throughout the system to determine control settings that move the system toward optimum performance as the load varies. The coordinated control provides set points to local controllers. A major difference between the coordinated control and local control is the set points provided by the coordinated control are
time varying. Reduction of energy and losses of coordinated control are compared with local control. Also eliminating low voltage problems with coordinated control…
Advisors/Committee Members: De La Reelopez, Jaime (committeechair), Broadwater, Robert P. (committeechair), Abbott, Amos L. (committee member), Ghandforoush, Parviz (committee member), Centeno, Virgilio A. (committee member).
Subjects/Keywords: Coordinated Control; Storm Restoration; Volt-Var Control; Distribution Automation; Economical Operation of Smart Grid; Time-Varying Analysis
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Onen, A. (2014). Model-Based Grid Modernization Economic Evaluation Framework. (Doctoral Dissertation). Virginia Tech. Retrieved from http://hdl.handle.net/10919/46981
Chicago Manual of Style (16th Edition):
Onen, Ahmet. “Model-Based Grid Modernization Economic Evaluation Framework.” 2014. Doctoral Dissertation, Virginia Tech. Accessed March 01, 2021.
http://hdl.handle.net/10919/46981.
MLA Handbook (7th Edition):
Onen, Ahmet. “Model-Based Grid Modernization Economic Evaluation Framework.” 2014. Web. 01 Mar 2021.
Vancouver:
Onen A. Model-Based Grid Modernization Economic Evaluation Framework. [Internet] [Doctoral dissertation]. Virginia Tech; 2014. [cited 2021 Mar 01].
Available from: http://hdl.handle.net/10919/46981.
Council of Science Editors:
Onen A. Model-Based Grid Modernization Economic Evaluation Framework. [Doctoral Dissertation]. Virginia Tech; 2014. Available from: http://hdl.handle.net/10919/46981

Penn State University
20.
Chen, Meng.
Stochastic Differential Equation Models with Time-Varying Parameters.
Degree: 2017, Penn State University
URL: https://submit-etda.libraries.psu.edu/catalog/14220mxc681
► Self-organization occurs when a system shows distinct shifts in dynamics due to variations in the parameters that govern the system. Relatedly, many human dynamic processes…
(more)
▼ Self-organization occurs when a system shows distinct shifts in dynamics due to variations in the parameters that govern the system. Relatedly, many human dynamic processes with self-organizing features comprise subprocesses that unfold across multiple
time scales. Incorporating
time-
varying parameters (TVPs) into a dynamic model of choice provides one way of representing self-organization as well as multi-
time scale processes. Extant applications involving models with TVPs have been restricted to formulation in discrete
time. Related work for representing
time-
varying parameters in continuous-
time models remains scarce. We propose a stochastic differential equation (SDE) modeling framework with TVPs as a way to capture self-organization in continuous
time. We present several examples of SDEs with TVPs, including a stochastic damped oscillator model with hypothesized functional shifts in both set-points and damping. Furthermore, we discuss plausible models that may be used to approximate changes in the TVPs in the absence of further knowledge concerning their true change mechanisms.
Advisors/Committee Members: Sy-Miin Chow, Thesis Advisor/Co-Advisor.
Subjects/Keywords: Stochastic Differential Equation; Time-varying Parameter
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Chen, M. (2017). Stochastic Differential Equation Models with Time-Varying Parameters. (Thesis). Penn State University. Retrieved from https://submit-etda.libraries.psu.edu/catalog/14220mxc681
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Chen, Meng. “Stochastic Differential Equation Models with Time-Varying Parameters.” 2017. Thesis, Penn State University. Accessed March 01, 2021.
https://submit-etda.libraries.psu.edu/catalog/14220mxc681.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Chen, Meng. “Stochastic Differential Equation Models with Time-Varying Parameters.” 2017. Web. 01 Mar 2021.
Vancouver:
Chen M. Stochastic Differential Equation Models with Time-Varying Parameters. [Internet] [Thesis]. Penn State University; 2017. [cited 2021 Mar 01].
Available from: https://submit-etda.libraries.psu.edu/catalog/14220mxc681.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Chen M. Stochastic Differential Equation Models with Time-Varying Parameters. [Thesis]. Penn State University; 2017. Available from: https://submit-etda.libraries.psu.edu/catalog/14220mxc681
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Delft University of Technology
21.
Cavallo, Gaia (author).
Skirt Decomposition Method for the Identification of Linear Time-Varying Human Joint Admittance.
Degree: 2017, Delft University of Technology
URL: http://resolver.tudelft.nl/uuid:3187dfa9-8728-452e-88ed-a7af1e0a9f3a
► Human joint admittance changes with numerous factors constituting the operational point. For large changes of the operational point, joint admittance can be identified using Linear…
(more)
▼ Human joint admittance changes with numerous factors constituting the operational point. For large changes of the operational point, joint admittance can be identified using Linear Time-Varying methods on torque and angular position signals measured on human joints. Out of the available methods, the Skirt Decomposition method was selected due to its nonparametric structure and the limited number of a priori assumptions it makes. Its employment on the identification of human joint admittance was completely novel. The method was applied to a simulation model representing joint admittance and on experimental data measured from the wrist joint. In the experiment, the subjects were changing the applied torque to follow a desired trajectory, while the angle of the wrist was perturbed by the manipulator.With a properly designed multisine input, taking into consideration the speed and complexity of the time variation, a variance accounted for (VAF) close to 100 % was obtained in the simulation study on all the tested conditions. From the experiment, it was seen that the contribution of the time variation in the frequency domain was partially masked by the output noise. The noise level could be decreased by lowering the amplitude of the desired torque, and by removing the voluntary torque from the analyzed data. With a desired torque level ranging between 5% and 20%, and considering the bandwidth between 2 Hz and 20 Hz, the mean power of the output residuals in the frequency domain ranged between 16.2 and 27.1 for all the tested conditions. Furthermore, the time-varying dynamics retrieved from the system function showed a clear correlation with the desired torque trajectory.
Systems and Control
Advisors/Committee Members: van Wingerden, Jan-Willem (mentor), Schouten, Alfred (mentor), van de Ruit, Mark (graduation committee), van de Plas, Raf (graduation committee), Lataire, John (graduation committee), Delft University of Technology (degree granting institution).
Subjects/Keywords: joint admittance; linear time-varying; multisine
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Cavallo, G. (. (2017). Skirt Decomposition Method for the Identification of Linear Time-Varying Human Joint Admittance. (Masters Thesis). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:3187dfa9-8728-452e-88ed-a7af1e0a9f3a
Chicago Manual of Style (16th Edition):
Cavallo, Gaia (author). “Skirt Decomposition Method for the Identification of Linear Time-Varying Human Joint Admittance.” 2017. Masters Thesis, Delft University of Technology. Accessed March 01, 2021.
http://resolver.tudelft.nl/uuid:3187dfa9-8728-452e-88ed-a7af1e0a9f3a.
MLA Handbook (7th Edition):
Cavallo, Gaia (author). “Skirt Decomposition Method for the Identification of Linear Time-Varying Human Joint Admittance.” 2017. Web. 01 Mar 2021.
Vancouver:
Cavallo G(. Skirt Decomposition Method for the Identification of Linear Time-Varying Human Joint Admittance. [Internet] [Masters thesis]. Delft University of Technology; 2017. [cited 2021 Mar 01].
Available from: http://resolver.tudelft.nl/uuid:3187dfa9-8728-452e-88ed-a7af1e0a9f3a.
Council of Science Editors:
Cavallo G(. Skirt Decomposition Method for the Identification of Linear Time-Varying Human Joint Admittance. [Masters Thesis]. Delft University of Technology; 2017. Available from: http://resolver.tudelft.nl/uuid:3187dfa9-8728-452e-88ed-a7af1e0a9f3a

University of Ottawa
22.
Doan, William.
Temporal Closeness in Knowledge Mobilization Networks
.
Degree: 2016, University of Ottawa
URL: http://hdl.handle.net/10393/34756
► In this thesis we study the impact of time in the analysis of social networks. To do that we represent a knowledge mobilization network, Knowledge-Net,…
(more)
▼ In this thesis we study the impact of time in the analysis of social networks. To do that we represent a knowledge mobilization network, Knowledge-Net, both as a standard static graph and a time-varying graph and study both graphs to see their differences. For our study, we implemented some temporal metrics and added them to Gephi, an open source software for graph and network analysis which already contains some static metrics. Then we used that software to obtain our results.
Knowledge-Net is a network built using the knowledge mobilization concept. In social science, knowledge mobilization is defined as the use of knowledge towards the achievement of goals. The networks which are built using the knowledge mobilization concept make more visible the relations among heterogeneous human and non-human individuals, organizational actors and non-human mobilization actors.
A time-varying graph is a graph with nodes and edges appearing and disappearing over time. A journey in a time-varying graph is equivalent to a path in a static graph. The notion of shortest path in a static graph has three variations in a time-varying graph: the shortest journey is the journey with the least number of temporal hops, the fastest journey is the journey that takes the least amount of time and the foremost journey is the journey that arrives the soonest. Out of those three, we focus on the foremost journey for our analysis.
Subjects/Keywords: algorithm;
time-varying graph;
closeness;
knowledge mobilization
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Doan, W. (2016). Temporal Closeness in Knowledge Mobilization Networks
. (Thesis). University of Ottawa. Retrieved from http://hdl.handle.net/10393/34756
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Doan, William. “Temporal Closeness in Knowledge Mobilization Networks
.” 2016. Thesis, University of Ottawa. Accessed March 01, 2021.
http://hdl.handle.net/10393/34756.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Doan, William. “Temporal Closeness in Knowledge Mobilization Networks
.” 2016. Web. 01 Mar 2021.
Vancouver:
Doan W. Temporal Closeness in Knowledge Mobilization Networks
. [Internet] [Thesis]. University of Ottawa; 2016. [cited 2021 Mar 01].
Available from: http://hdl.handle.net/10393/34756.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Doan W. Temporal Closeness in Knowledge Mobilization Networks
. [Thesis]. University of Ottawa; 2016. Available from: http://hdl.handle.net/10393/34756
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Universitat Pompeu Fabra
23.
Rossi, Luca.
Essays on volatility networks and uncertainty.
Degree: Departament d'Economia i Empresa, 2018, Universitat Pompeu Fabra
URL: http://hdl.handle.net/10803/565613
► Aquesta tesi investiga empíricament diferents aspectes de la volatilitat variable. El Capítol 1 estima un TVP-FAVAR i recupera una xarxa de connexions dinàmiques entre les…
(more)
▼ Aquesta tesi investiga empíricament diferents aspectes de la volatilitat variable. El Capítol 1 estima un TVP-FAVAR i recupera una xarxa de connexions dinàmiques entre les volatilitats de accions europees. Proposem una metodologia d’estimació ad-hoc que es demostri que supera els enfocaments estàndard i els models competidors. El Capítol 2 es centra en el seguiment de la connectivitat dinàmica entre les volatilitats sectorials dels Estats Units mitjançant descomposicions generalitzadas de variància d’errors de previsió amb un model Bayesià. A diferència de les estimacions obtingudes amb finestres enrotllables, permetem que els paràmetres variïn de manera més flexible. Mostrem que existeix una relació estable entre l’estructura de la xarxa i els règims de volatilitat vigents en un moment determinat. El Capítol 3 estima el component variable inesperat de la volatilitat dels pressupostos fiscals a Itàlia. Mostrem que els períodes de major volatilitat fiscal inesperada probablement són recessius. Les polítiques expansives només són efectives quan no s’acompanyen d’increments d’incertesa.
Advisors/Committee Members: [email protected] (authoremail), true (authoremailshow), Rossi, Barbara, 1971- (director), Brownlees, Christian, 1979- (director), true (authorsendemail).
Subjects/Keywords: Time-varying volatility; Volatilitat variable; 33
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Rossi, L. (2018). Essays on volatility networks and uncertainty. (Thesis). Universitat Pompeu Fabra. Retrieved from http://hdl.handle.net/10803/565613
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Rossi, Luca. “Essays on volatility networks and uncertainty.” 2018. Thesis, Universitat Pompeu Fabra. Accessed March 01, 2021.
http://hdl.handle.net/10803/565613.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Rossi, Luca. “Essays on volatility networks and uncertainty.” 2018. Web. 01 Mar 2021.
Vancouver:
Rossi L. Essays on volatility networks and uncertainty. [Internet] [Thesis]. Universitat Pompeu Fabra; 2018. [cited 2021 Mar 01].
Available from: http://hdl.handle.net/10803/565613.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Rossi L. Essays on volatility networks and uncertainty. [Thesis]. Universitat Pompeu Fabra; 2018. Available from: http://hdl.handle.net/10803/565613
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Sydney
24.
Huang, Danlan.
Entrainment in Pulsing plumes
.
Degree: 2019, University of Sydney
URL: http://hdl.handle.net/2123/21168
► The main contribution of this work is to investigate the entrainment in plumes with constant and time-varying source conditions experimentally. The study aims to build…
(more)
▼ The main contribution of this work is to investigate the entrainment in plumes with constant and time-varying source conditions experimentally. The study aims to build up an experiment rig to conduct the bulk entrainment measurement in plumes. Secondly, the study aims to examine the influences the forcing frequency and amplitude have on entrainment in pulsing plumes, where the flow rate, momentum and buoyancy are sinusoidal functions of time. Finally, the study aims to investigate the validity of the integral model for pure plumes with constant source conditions established by Morton et al. (Proc R Soc Lond A 234(1196):1–23, 1956) in pulsing plumes, as well as the virtual origin correction method for lazy plumes proposed by Hunt and Kaye (J Fluid Mech 435:377–396, 2001) in both constant source plumes and pulsing plumes. Experiments were conducted to verify the pulses in pulsing plumes. Plumes are formed by issuing saline fluid downwards into a less dense uniform environment from a round pipe. The pulsing flow is generated by a programmable ISMATEC gear pump. The evolution of the pulses in pulsing plumes is revealed by applying the light-attenuation method with high frequency imaging. Pulsing is shown to affect the development of the flow, as the forcing frequency at the source dominates the frequency of the flow downstream. To study the bulk entrainment in pulsing plumes, turbulent axisymmetric lazy plumes with constant source conditions were examined initially. The bulk dilution and entrainment measurements were achieved by using the experimental approach of Hunt and Kaye (J Fluid Mech 435:377–396, 2001). The integral relationship for the local flow rate Q(z) and local momentum M(z) from the model established by Morton et al. (Proc R Soc Lond A 234(1196):1–23, 1956) for constant source plumes was used to determine the average local entrainment. Experiments with pulsing plumes were carried out with a flow rate amplitude ranged from 33% to 80% and the non-dimensional frequency - Strouhal number 〖St=fD/U〗_0 ranged from 0.012 to 1.2, where the maximum frequency f of this pulsing plume is in the order of the eddy turnover time scale at the source, D is the source diameter and U_0 is the average velocity at the source. The entrainment coefficient was determined in pulsing plumes and was found within the range of the entrainment values in plumes with constant source conditions. The influence of the forcing frequency and amplitude is examined, and found to be very small over the entire range of source conditions considered. The virtual origin correction method of Hunt and Kaye (J Fluid Mech 435:377–396, 2001) is found to give a reasonably good estimation in predicting the virtual origin in pulsing plumes. The results suggest that the local entrainment velocity is proportional to the time-average local plume velocity even in pulsing plumes where the local velocity is varying with time. This supports the application of the integral model of Morton et al. (Proc R Soc Lond A 234(1196):1–23, 1956) to building…
Subjects/Keywords: Entrainment;
plumes;
turbulent mixing;
time-varying source
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Huang, D. (2019). Entrainment in Pulsing plumes
. (Thesis). University of Sydney. Retrieved from http://hdl.handle.net/2123/21168
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Huang, Danlan. “Entrainment in Pulsing plumes
.” 2019. Thesis, University of Sydney. Accessed March 01, 2021.
http://hdl.handle.net/2123/21168.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Huang, Danlan. “Entrainment in Pulsing plumes
.” 2019. Web. 01 Mar 2021.
Vancouver:
Huang D. Entrainment in Pulsing plumes
. [Internet] [Thesis]. University of Sydney; 2019. [cited 2021 Mar 01].
Available from: http://hdl.handle.net/2123/21168.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Huang D. Entrainment in Pulsing plumes
. [Thesis]. University of Sydney; 2019. Available from: http://hdl.handle.net/2123/21168
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of North Texas
25.
Palka, Jayme M.
Class Enumeration and Parameter Bias in Growth Mixture Models with Misspecified Time-Varying Covariates: A Monte Carlo Simulation Study.
Degree: 2020, University of North Texas
URL: https://digital.library.unt.edu/ark:/67531/metadc1752343/
► Growth mixture modeling (GMM) is a useful tool for examining both between- and within-persons change over time and uncovering unobserved heterogeneity in growth trajectories. Importantly,…
(more)
▼ Growth mixture modeling (GMM) is a useful tool for examining both between- and within-persons change over
time and uncovering unobserved heterogeneity in growth trajectories. Importantly, the correct extraction of latent classes and parameter recovery can be dependent upon the type of covariates used.
Time-
varying covariates (TVCs) can influence class membership but are scarcely included in GMMs as predictors. Other times, TVCs are incorrectly modeled as
time-invariant covariates (TICs). Additionally, problematic results can occur with the use of maximum likelihood (ML) estimation in GMMs, including convergence issues and sub-optimal maxima. In such cases, Bayesian estimation may prove to be a useful solution. The present Monte Carlo simulation study aimed to assess class enumeration accuracy and parameter recovery of GMMs with a TVC, particularly when a TVC has been incorrectly specified as a TIC. Both ML estimation and Bayesian estimation were examined. Results indicated that class enumeration indices perform less favorably in the case of TVC misspecification, particularly absolute class enumeration indices. Additionally, in the case of TVC misspecification, parameter bias was found to be greater than the generally accepted cutoff of 10%, particularly for variance estimates. It is recommended that researchers continue to use a variety of class enumeration indices during class enumeration, particularly relative indices. Additionally, researchers should take caution when interpreting variance parameter estimates when the GMM contains a misspecified TVC.
Advisors/Committee Members: Henson, Robin K., Tashakkori, Abbas, Savage, Melissa, Ferguson, Sarah.
Subjects/Keywords: Growth mixture modeling; time-varying covariates; MCMC
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University of Waterloo
26.
Aladdini, Kian.
EMS Response Time Models: A Case Study and Analysis for the Region of Waterloo.
Degree: 2010, University of Waterloo
URL: http://hdl.handle.net/10012/5034
► Ambulance response time is a key measure used to assess EMS system performance. However, the speed with which ambulances respond to emergencies can be highly…
(more)
▼ Ambulance response time is a key measure used to assess EMS system performance. However, the speed with which ambulances respond to emergencies can be highly variable. In some cases, this is due to geography. In dense urban areas for example, the distances traveled are short, but traffic and other hindrances such as traffic calming measures and high rise elevators cause delays, while rural areas involve greater distances and longer travel times. There are two major components of response time: first, pre-travel delay to prepare for ambulance dispatch, and second the actual travel time to the callers location.
Response time standards are often established in order to provide fast and reliable service to the most severely ill patients. Standards typically specify the percentage of time an emergency response team can get to a call within a certain time threshold. This is referred to as “coverage”. This thesis deals with the development of a new response time model that predicts not only the mean response time, but estimates its variability. The models are developed based on historical data provided by the Region of Waterloo EMS and will permit the Region to predict EMS coverage.
By analyzing the historical data, we found that response times from EMS stations to geographical locations within the Region of Waterloo are characterized by lognormal distributions. For a particular station – location pair we can thus use this information to predict coverage if we are able to specify the parameters of the distribution. We do this by characterizing the travel time and pre-travel delay times separately, and then adding the two to estimate coverage.
We will use a previously proposed model that estimates the mean travel time from a station to a demand point as a function of road types traversed. We also compare the results of this model with another well known model and show that the first model is suitable to apply to the Region of Waterloo. In order to estimate the standard deviation of the response time, we propose a simple but effective model that estimates the standard deviation as a function of mean response time.
Subjects/Keywords: Ambulance response time; EMS; Travel time; Probability of coverage
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Aladdini, K. (2010). EMS Response Time Models: A Case Study and Analysis for the Region of Waterloo. (Thesis). University of Waterloo. Retrieved from http://hdl.handle.net/10012/5034
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Aladdini, Kian. “EMS Response Time Models: A Case Study and Analysis for the Region of Waterloo.” 2010. Thesis, University of Waterloo. Accessed March 01, 2021.
http://hdl.handle.net/10012/5034.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Aladdini, Kian. “EMS Response Time Models: A Case Study and Analysis for the Region of Waterloo.” 2010. Web. 01 Mar 2021.
Vancouver:
Aladdini K. EMS Response Time Models: A Case Study and Analysis for the Region of Waterloo. [Internet] [Thesis]. University of Waterloo; 2010. [cited 2021 Mar 01].
Available from: http://hdl.handle.net/10012/5034.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Aladdini K. EMS Response Time Models: A Case Study and Analysis for the Region of Waterloo. [Thesis]. University of Waterloo; 2010. Available from: http://hdl.handle.net/10012/5034
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Texas A&M University
27.
Lee, Jun Bum.
A Novel Approach to the Analysis of Nonlinear Time Series with Applications to Financial Data.
Degree: PhD, Statistics, 2012, Texas A&M University
URL: http://hdl.handle.net/1969.1/ETD-TAMU-2012-05-10928
► The spectral analysis method is an important tool in time series analysis and the spectral density plays a crucial role on the spectral analysis. However,…
(more)
▼ The spectral analysis method is an important tool in
time series analysis and the spectral
density plays a crucial role on the spectral analysis. However, one of limitations of the spectral
density is that the spectral
density reflects only the covariance structure among several dependence measures in the
time series data. To overcome this restriction, we define two spectral densities, the quantile spectral
density and the association spectral
density. The quantile spectral
density can model the pairwise dependence structure and provide identification of nonlinear
time series and the association spectral
density allows detecting periodicities on different parts of the domain of the
time series. We propose the estimators for the quantile spectral
density and the association spectral
density and derive their sampling properties including asymptotic normality. Furthermore, we use the quantile spectral
density to develop a goodness-of-fit tests for
time series and explain how this test can be used for comparing the sequential dependence structure of two
time series. The asymptotic sampling properties of the test statistic are derived under the null and alternative hypothesis, and a bootstrap procedure is suggested to obtain finite sample approximation. The method is illustrated with simulations and some real data examples. Besides the exploration of the new spectral densities, we consider general quadratic forms of alpha-mixing
time series and derive asymptotic normality of these forms under the relatively weak assumptions.
Advisors/Committee Members: Subba Rao, Suhasini (advisor), Pourahmadi, Mohsen (committee member), Lahiri, Soumendra N. (committee member), Kim, Hwagyun (committee member).
Subjects/Keywords: goodness-of-fit test; nonlinear time series; quantile spectral density; association spectral density
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Lee, J. B. (2012). A Novel Approach to the Analysis of Nonlinear Time Series with Applications to Financial Data. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2012-05-10928
Chicago Manual of Style (16th Edition):
Lee, Jun Bum. “A Novel Approach to the Analysis of Nonlinear Time Series with Applications to Financial Data.” 2012. Doctoral Dissertation, Texas A&M University. Accessed March 01, 2021.
http://hdl.handle.net/1969.1/ETD-TAMU-2012-05-10928.
MLA Handbook (7th Edition):
Lee, Jun Bum. “A Novel Approach to the Analysis of Nonlinear Time Series with Applications to Financial Data.” 2012. Web. 01 Mar 2021.
Vancouver:
Lee JB. A Novel Approach to the Analysis of Nonlinear Time Series with Applications to Financial Data. [Internet] [Doctoral dissertation]. Texas A&M University; 2012. [cited 2021 Mar 01].
Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2012-05-10928.
Council of Science Editors:
Lee JB. A Novel Approach to the Analysis of Nonlinear Time Series with Applications to Financial Data. [Doctoral Dissertation]. Texas A&M University; 2012. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2012-05-10928

University of Tennessee – Knoxville
28.
Van Wesep, Robert Gerard.
Optical Spectroscopy and the Contruction of an Optimal Wannier Basis with Application to the Development of <i>Ab Initio</i> Models.
Degree: 2016, University of Tennessee – Knoxville
URL: https://trace.tennessee.edu/utk_graddiss/4112
► Understanding the role of local orbital degrees of freedom in the behavior of solid state systems has long been understood as a key to unraveling…
(more)
▼ Understanding the role of local orbital degrees of freedom in the behavior of solid state systems has long been understood as a key to unraveling the mysteries presented by complex transition metal compounds. A general approach to the many-body problem is density functional theory (DFT) and its time-dependent extension (TDDFT), which provide a realistic representation of the material-dependent symmetry and chemistry of a compound. Calculation of quantities in (TD)DFT are most often performed using the basis of Bloch states, which is not natural for investigating local degrees of freedom. The Wannier basis provides localized orbitals that retain all of the information on the chemistry and symmetry of the groundstate. By transforming the expressions from TDDFT for the density-response functions into the Wannier basis, I have been able to develop novel methods for the investigation into the role of orbital degrees of freedom on the particle-hole excitation spectrum and used these methods to develop a scheme to construct a Wannier basis by tuning the gauge of the transformation to produce the simplest, yet fully accurate, description of the low-energy optical spectrum. Cu2O [cuprite] provided the foundational test case for this development and the key to optimization proved to be the transference of chemically induced hybridization from energy space into real space. Using FeTe as a test case for correlated materials required understanding its graphene-like optical response, which I explain as a result of orbitally selective, local correlations giving rise to two-dimensional, linearly dispersing band topology. I also interpret the correlations and optical excitations using the Wannier basis. Subsequently, I have extended the optimization method to FeTe, which led naturally to 1) a "target" subspace of the full Hilbert space that is disentangled from the "rest", allowing for the construction of minimal, ab initio models by utilizing the constrained random-phase approximation (CRPA) and 2) ordered molecular orbitals that correspond to the structural and magnetic phase transition. The results contained in this dissertation will have broad implications for the treatment of long-ranged physics in future theoretical approaches to complex transition metal compounds.
Subjects/Keywords: Solid State Physics; Condensed Matter Physics; Time-Dependent Density Functional Theory; Wannier Functions; Copper Oxides; Iron-based Superconductors; Condensed Matter Physics
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Van Wesep, R. G. (2016). Optical Spectroscopy and the Contruction of an Optimal Wannier Basis with Application to the Development of <i>Ab Initio</i> Models. (Doctoral Dissertation). University of Tennessee – Knoxville. Retrieved from https://trace.tennessee.edu/utk_graddiss/4112
Chicago Manual of Style (16th Edition):
Van Wesep, Robert Gerard. “Optical Spectroscopy and the Contruction of an Optimal Wannier Basis with Application to the Development of <i>Ab Initio</i> Models.” 2016. Doctoral Dissertation, University of Tennessee – Knoxville. Accessed March 01, 2021.
https://trace.tennessee.edu/utk_graddiss/4112.
MLA Handbook (7th Edition):
Van Wesep, Robert Gerard. “Optical Spectroscopy and the Contruction of an Optimal Wannier Basis with Application to the Development of <i>Ab Initio</i> Models.” 2016. Web. 01 Mar 2021.
Vancouver:
Van Wesep RG. Optical Spectroscopy and the Contruction of an Optimal Wannier Basis with Application to the Development of <i>Ab Initio</i> Models. [Internet] [Doctoral dissertation]. University of Tennessee – Knoxville; 2016. [cited 2021 Mar 01].
Available from: https://trace.tennessee.edu/utk_graddiss/4112.
Council of Science Editors:
Van Wesep RG. Optical Spectroscopy and the Contruction of an Optimal Wannier Basis with Application to the Development of <i>Ab Initio</i> Models. [Doctoral Dissertation]. University of Tennessee – Knoxville; 2016. Available from: https://trace.tennessee.edu/utk_graddiss/4112

University of Rochester
29.
Forrest, Chad James (1978 - ); Meyerhofer, David Dietrich.
Measurements of the fuel distribution in cryogenic D-T
direct-drive implosions.
Degree: PhD, 2015, University of Rochester
URL: http://hdl.handle.net/1802/30236
► In direct-drive inertial confinement fusion (ICF) experiments, a capsule filled with a mixture of deuterium and tritium ice at cryogenic temperature is irradiated by a…
(more)
▼ In direct-drive inertial confinement fusion (ICF)
experiments, a capsule filled with a mixture of deuterium and
tritium ice at cryogenic temperature is irradiated by a symmetric
arrangements of laser beams to compress and heat the fuel to
conditions required for thermonuclear reactions. The areal density
(ρR) of the compressed fuel assembly in a cryogenic implosion is
one of the fundamental parameters required to assess the target
performance.
</br>
The ρR measurements
presented here are achieved by measuring the complex neutron energy
spectrum resulting from primary and secondary nuclear reactions
within the compressed fuel assembly. Advances in neutron
time-of-flight diagnostics have made it possible to infer the
neutron fraction that elastically scatters off the tritons in the
compressed fuel in the energy range from 3.5 -5.5 MeV which is
directly proportional to the areal density.
</br>
In these OMEGA cryogenic campaigns from January 2013 to August
2014, measured low-mode modulations show good agreement with Monte
Carlo simulations. Deviations up to 40% in the cold-fuel
distribution from spherical symmetry have been inferred from the
scattered neutron spectrum. Understanding the mechanism for
anisotropic areal density measurements is crucial to improve
hydrodynamically equivalent ignition-relevant direct-drive
cryogenic implosions on OMEGA.
Subjects/Keywords: Areal density; Down-scattered fraction; Neutron time-of-flight (nTOF)
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Forrest, Chad James (1978 - ); Meyerhofer, D. D. (2015). Measurements of the fuel distribution in cryogenic D-T
direct-drive implosions. (Doctoral Dissertation). University of Rochester. Retrieved from http://hdl.handle.net/1802/30236
Chicago Manual of Style (16th Edition):
Forrest, Chad James (1978 - ); Meyerhofer, David Dietrich. “Measurements of the fuel distribution in cryogenic D-T
direct-drive implosions.” 2015. Doctoral Dissertation, University of Rochester. Accessed March 01, 2021.
http://hdl.handle.net/1802/30236.
MLA Handbook (7th Edition):
Forrest, Chad James (1978 - ); Meyerhofer, David Dietrich. “Measurements of the fuel distribution in cryogenic D-T
direct-drive implosions.” 2015. Web. 01 Mar 2021.
Vancouver:
Forrest, Chad James (1978 - ); Meyerhofer DD. Measurements of the fuel distribution in cryogenic D-T
direct-drive implosions. [Internet] [Doctoral dissertation]. University of Rochester; 2015. [cited 2021 Mar 01].
Available from: http://hdl.handle.net/1802/30236.
Council of Science Editors:
Forrest, Chad James (1978 - ); Meyerhofer DD. Measurements of the fuel distribution in cryogenic D-T
direct-drive implosions. [Doctoral Dissertation]. University of Rochester; 2015. Available from: http://hdl.handle.net/1802/30236

University of Georgia
30.
Abbasi Doustvatan, Farshid.
Coverage control for heterogeneous multi-agent systems.
Degree: 2017, University of Georgia
URL: http://hdl.handle.net/10724/36554
► In the present dissertation, a team-based coverage control is proposed that aims at deploying groups of agents to an environment with a probability distribution function…
(more)
▼ In the present dissertation, a team-based coverage control is proposed that aims at deploying groups of agents to an environment with a probability distribution function representing the likelihood of an event in different regions. The
proposed approach can handle the deployment of heterogeneous teams agents each of which pursing a different objective or assigned task. The presented approaches are then implemented on a set of numerical examples to asses their performance. As the next
task and in a different domain, the development of robust nonlinear control techniques is studied for uncertain systems. Various types of uncertainty is investigated in three major areas; first, a robust identification approach is proposed for the
emph{Linear Parameter Varying} (LPV) identification of nonlinear systems with uncertain Scheduling variables. Two deterministic and stochastic techniques are developed and their performance are compared with the previous methods in the literature. Next,
a robust reduced-order model based controller is designed for a system represented by a parabolic emph{Partial Differential Equation} (PDE). The objective is to take into account the variation of the model parameter and its effect on the reduced-order
model. Then, the reduced model is used to design a robust nonlinear controller to control the main full-order model.
Subjects/Keywords: Multi-agent Systems; heterogeneous agents; coverage control; team-based coverage; Linear Parameter-varying Models; System Identification; Robust Control; Nonlinear Control
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Abbasi Doustvatan, F. (2017). Coverage control for heterogeneous multi-agent systems. (Thesis). University of Georgia. Retrieved from http://hdl.handle.net/10724/36554
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Abbasi Doustvatan, Farshid. “Coverage control for heterogeneous multi-agent systems.” 2017. Thesis, University of Georgia. Accessed March 01, 2021.
http://hdl.handle.net/10724/36554.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Abbasi Doustvatan, Farshid. “Coverage control for heterogeneous multi-agent systems.” 2017. Web. 01 Mar 2021.
Vancouver:
Abbasi Doustvatan F. Coverage control for heterogeneous multi-agent systems. [Internet] [Thesis]. University of Georgia; 2017. [cited 2021 Mar 01].
Available from: http://hdl.handle.net/10724/36554.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Abbasi Doustvatan F. Coverage control for heterogeneous multi-agent systems. [Thesis]. University of Georgia; 2017. Available from: http://hdl.handle.net/10724/36554
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
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