Tesis:

1

Stahl, David J. Jr. "Bag-of-particles as a deformable model". Diss., Georgia Institute of Technology, 2001. http://hdl.handle.net/1853/32952.

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2

Alirezaye-Davatgar, Mohammad Taghi Graduate School of Biomedical Engineering Faculty of Engineering UNSW. "Numerical simulation of blood flow in the systemic vasculature incorporating gravitational force with application to the cerebral circulation". Awarded by:University of New South Wales. Graduate School of Biomedical Engineering, 2006. http://handle.unsw.edu.au/1959.4/26177.

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Background. Extensive studies have been conducted to simulate blood flow in the human vasculature using nonlinear equations of pulsatile flow in collapsible tube plus a network of vessels to represent the whole vasculature and the cerebral circulation. For non-linear models numerical solutions are obtained for the fluid flow equations. Methods. Equations of fluid motion in collapsible tubes were developed in the presence of gravitational force (Gforce). The Lax-Wendroff and MacCormack methods were used to solve the governing equations and compared both in terms of accuracy, convergence, and computer processing (CPU) time. A modified vasculature of the whole body and the cerebral circulation was developed to obtain a realistic simulation of blood flow under different conditions. The whole body vasculature was used to validate the simulation in terms of input impedance and wave transmission. The cerebral vasculature was used to simulate conditions such as presence of G-force, blockage of Internal Carotid Artery (ICA), and the effects on cerebral blood flow of changes in mean and pulse pressure. Results. The simulation results for zero G-force were in very good agreement with published experimental data as was the simulation of cerebral blood flow. Both numerical methods for solutions of governing equations gave similar results for blood flow simulations but differed in calculation performance and stability depending on levels of G-force. Simulation results for uniform and sinusoidal G-force are also in good agreement with published experimental results, Blood flow was simulated in the presence of a single (left) carotid artery obstruction with varying morphological structures of the Circle of Willis (CoW). This simulation showed significant differences in contralateral blood flow in the presence or absence of communicating arteries in the CoW. It also was able to simulate the decreases in blood flow in the cerebral circulation compartment corresponding to the visual cortex in the presence of G-force. This is consistent with the known loss of vision under increased acceleration. Conclusions. This study has shown that under conditions of gravitational forces physiological changes in blood flow in the systemic and cerebral vasculature can be simulated realistically by solving the one-dimentional fluid flow equations and non-linear vascular properties numerically. The simulation was able to predict changes in blood flow with different configurations and properties of the vascular network.

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3

Du, Dongping. "Physical-Statistical Modeling and Optimization of Cardiovascular Systems". Scholar Commons, 2002. http://scholarcommons.usf.edu/etd/5875.

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Heart disease remains the No.1 leading cause of death in U.S. and in the world. To improve cardiac care services, there is an urgent need of developing early diagnosis of heart diseases and optimal intervention strategies. As such, it calls upon a better understanding of the pathology of heart diseases. Computer simulation and modeling have been widely applied to overcome many practical and ethical limitations in in-vivo, ex-vivo, and whole-animal experiments. Computer experiments provide physiologists and cardiologists an indispensable tool to characterize, model and analyze cardiac function both in healthy and in diseased heart. Most importantly, simulation modeling empowers the analysis of causal relationships of cardiac dysfunction from ion channels to the whole heart, which physical experiments alone cannot achieve. Growing evidences show that aberrant glycosylation have dramatic influence on cardiac and neuronal function. Variable but modest reduction in glycosylation among congenital disorders of glycosylation (CDG) subtypes has multi-system effects leading to a high infant mortality rate. In addition, CDG in all young patients tends to cause Atrial Fibrillation (AF), i.e., the most common sustained cardiac arrhythmia. The mortality rate from AF has been increasing in the past two decades. Due to the increasing healthcare burden of AF, studying the AF mechanisms and developing optimal ablation strategies are now urgently needed. Very little is known about how glycosylation modulates cardiac electrical signaling. It is also a significant challenge to experimentally connect the changes at one organizational level (e.g.,electrical conduction among cardiac tissue) to measured changes at another organizational level (e.g., ion channels). In this study, we integrate the data from in vitro experiments with in-silico models to simulate the effects of reduced glycosylation on the gating kinetics of cardiac ion channel, i.e., hERG channels, Na+ channels, K+ channels, and to predict the glycosylation modulation dynamics in individual cardiac cells and tissues. The complex gating kinetics of Na+ channels is modeled with a 9-state Markov model that have voltage-dependent transition rates of exponential forms. The model calibration is quite a challenge as the Markov model is non-linear, non-convex, ill-posed, and has a large parametric space. We developed a new metamodel-based simulation optimization approach for calibrating the model with the in-vitro experimental data. This proposed algorithm is shown to be efficient in learning the Markov model of Na+ model. Moreover, it can be easily transformed and applied to many other optimization problems in computer modeling. In addition, the understanding of AF initiation and maintenance has remained sketchy at best. One salient problem is the inability to interpret intracardiac recordings, which prevents us from reconstructing the rhythmic mechanisms for AF, due to multiple wavelets' circulating, clashing and continuously changing direction in the atria. We are designing computer experiments to simulate the single/multiple activations on atrial tissues and the corresponding intra-cardiac signals. This research will create a novel computer-aided decision support tool to optimize AF ablation procedures.

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4

Ojeda, Avellaneda David. "Multi-resolution physiological modeling for the analysis of cardiovascular pathologies". Phd thesis, Université Rennes 1, 2013. http://tel.archives-ouvertes.fr/tel-01056825.

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This thesis presents three main contributions in the context of modeling and simulation of physiological systems. The first one is a formalization of the methodology involved in multi-formalism and multi-resolution modeling. The second one is the presentation and improvement of a modeling and simulation framework integrating a range of tools that help the definition, analysis, usage and sharing of complex mathematical models. The third contribution is the application of this modeling framework to improve diagnostic and therapeutic strategies for clinical applications involving the cardiovascular system: hypertension-based heart failure (HF) and coronary artery disease (CAD). A prospective application in cardiac resynchronization therapy (CRT) is also presented, which also includes a model of the therapy. Finally, a final application is presented for the study of the baroreflex responses in the newborn lamb. These case studies include the integration of a pulsatile heart into a global cardiovascular model that captures the short and long term regulation of the cardiovascular system with the representation of heart failure, the analysis of coronary hemodynamics and collateral circulation of patients with triple-vessel disease enduring a coronary artery bypass graft surgery, the construction of a coupled electrical and mechanical cardiac model for the optimization of atrio ventricular and intraventricular delays of a biventricular pacemaker, and a model-based estimation of sympathetic and vagal responses of premature newborn lambs.

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5

Rocha, Felipe Figueredo. "Aspectos básicos da modelagem multiescala de tecidos biológicos". Laboratório Nacional de Computação Científica, 2014. https://tede.lncc.br/handle/tede/206.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
Fundação Carlos Chagas Filho de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ)
A detailed mechanical behaviour of the arterial wall is required to gain insight on the onset and progress of some cardiovascular diseases as well as to propose adequate treatments. The classical constitutive modelling approach based purely on phenomenological laws fails in representing the micromechanical phenomena which dominates important aspects of these tissues such as remodelling and rupture. In turn, the multi-scale constitutive modelling raises as a more rational alternative that allows to consider the microscopic features and interactions of the basic unit blocks of the biological tissues such as the existence of the collagen fibres,pores, etc. In this work we review the non-linear solid mechanics fundamental concepts, the linearisation of the variational principles, numerical treatment of incompressibility constraint as well the continuum damage theory. A constitutive multi-scale theory based on the existence of Representative Volume Element in the finite strain regime is presented in a variational formulation framework, where homogenization for the displacement and deformation gradient are assumed as well the energetic coupling between scales through a extended version of the Hill-Mandel principle. In this context, a number of simulations are discussed. Finally, as corollary of the continuum mechanics framework, we derive a strategy for the damage field identification which is based on the sensibility analysis of a cost functional which takes account the displacement and energies diferences.
Sabe-se que o conhecimento do comportamento mecânico da parede arterial è fundamental para a compreensão de diversas doenças cardiovasculares bem como o planejamento adequado do tratamento destas. Contudo a modelagem da resposta constitutiva deste tecido é complexa sendo que a abordagem clássica baseada puramente em leis fenomenológicas _e insuficiente para representar fenômenos micromecânicos, os quais, ademais, dominam aspectos tais como remodelagem e ruptura. A modelagem multiescala de tecidos biológicos surge então como uma alternativa mais racional para representar a resposta constitutiva destes materiais levando-se em consideração aspectos microscópicos da organização do tecido como a existência de fibras de colágeno, poros, etc. Neste trabalho revisamos os conceitos fundamentais da mecânica dos sólidos não-linear incluindo a linearização dos princípios variacionais, bem como os aspectos básicos das teoria constitutiva em grandes deformações, passando pelo tratamento da condição de incompressibilidade e a teoria do dano contínuo. Uma teoria constitutiva multiescala baseada na homogenização em um Elemento de Volume Representativo em regime de grandes deformações é apresentada em um contexto de formulações variacionais, sendo assumida a homogeneização do campo de deslocamentos e do gradiente de deformação, além da consistência energética entre escalas baseada no princípio de Hill-Mandel. Neste contexto, diversas simulações são apresentadas e discutidas. Porém, como corolário da abordagem da mecânica do contínuo, mostramos uma estratégia para a identificação do campo de dano baseado na análise de sensibilidade de um funcional custo baseado nas diferenças de campos de deslocamentos e energia de deformação.

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6

Chen, Chun-Cheng Richard 1977. "Automated cardiovascular system identification". Thesis, Massachusetts Institute of Technology, 2000. http://hdl.handle.net/1721.1/81537.

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Thesis (S.B. and M.Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2000.
Includes bibliographical references (p. 64-65).
by Chun-Cheng Chen.
S.B.and M.Eng.

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7

Maa, Ming-Hokng 1977. "Alterations in cardiovascular regulation and function assessed using cardiovascular system identification". Thesis, Massachusetts Institute of Technology, 2000. http://hdl.handle.net/1721.1/86525.

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Thesis (S.B. and M.Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2000.
Includes bibliographical references (p. 65-67).
by Ming-Hokng Maa.
S.B.and M.Eng.

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8

Maksuti, Elira. "Imaging and modeling the cardiovascular system". Doctoral thesis, KTH, Medicinsk bildteknik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-196538.

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Understanding cardiac pumping function is crucial to guiding diagnosis, predicting outcomes of interventions, and designing medical devices that interact with the cardiovascular system. Computer simulations of hemodynamics can show how the complex cardiovascular system is influenced by changes in single or multiple parameters and can be used to test clinical hypotheses. In addition, methods for the quantification of important markers such as elevated arterial stiffness would help reduce the morbidity and mortality related to cardiovascular disease. The general aim of this thesis work was to improve understanding of cardiovascular physiology and develop new methods for assisting clinicians during diagnosis and follow-up of treatment in cardiovascular disease. Both computer simulations and medical imaging were used to reach this goal. In the first study, a cardiac model based on piston-like motions of the atrioventricular plane was developed. In the second study, the presence of the anatomical basis needed to generate hydraulic forces during diastole was assessed in heathy volunteers. In the third study, a previously validated lumped-parameter model was used to quantify the contribution of arterial and cardiac changes to blood pressure during aging. In the fourth study, in-house software that measures arterial stiffness by ultrasound shear wave elastography (SWE) was developed and validated against mechanical testing. The studies showed that longitudinal movements of the atrioventricular plane can well explain cardiac pumping and that the macroscopic geometry of the heart enables the generation of hydraulic forces that aid ventricular filling. Additionally, simulations showed that structural changes in both the heart and the arterial system contribute to the progression of blood pressure with age. Finally, the SWE technique was validated to accurately measure stiffness in arterial phantoms.

QC 20161115

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9

Zhang, Guoging 1963. "Knowledge based simulation system--an application in controlled environment simulation system". Thesis, The University of Arizona, 1988. http://hdl.handle.net/10150/292001.

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This thesis systematically identifies the building blocks of a knowledge based system for simulation and modelling. We present the design and implementation of Controlled Environment Simulation System (CESS), which bridges a discrete event simulation system (DEVS-SCHEME) and a continuous simulation system (TRNSYS). The rationale behind the approach is that a discrete or a continuous model can be abstracted to a level at which the uniform treatment on these two kinds of models is possible. A top-down approach to model creation (abstraction) is proposed, in contrast to the traditional bottom-up approach. CESS is implemented on an object-oriented programming environment (SCOOPS on TI-SCHEME). A knowledge representation scheme known as System Entity Structure is employed for MODEL management, recording system structural knowledge, and the utilization of techniques in Artificial Intelligence. Some prospective research topics are also brought up.

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10

Belote, Greg H. "Multivehicle simulation system". Thesis, Massachusetts Institute of Technology, 2008. http://hdl.handle.net/1721.1/45812.

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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2008.
Includes bibliographical references (p. 39).
In this thesis, we designed and implemented a simulator that supports multiple robots within a dynamic environment. The goal of this tool is to provide a testing environment for navigational robots that run on the MOOS platform. The simulator is written in C++ and utilizes several open source libraries to create a virtual world for robots to interact with by faking sensor information. A design goal of this thesis has been to make the simulator versatile enough to be useful for a variety of robots, from land to marine. Such a tool is valuable in research because the cost of developing a custom simulator can consume too many man-hours. Reducing this cost by creating a generic and customizable simulator has been the main motivation behind this thesis. It has also been one of the major challenges behind the project.
by Greg H. Belote.
M.Eng.

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11

Zoorob, Riad J. "S.E.S., a simulation expert system". Virtual Press, 1994. http://liblink.bsu.edu/uhtbin/catkey/897507.

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The continuous increase in the cost of building real life projects, the high cost of researches concerning a project and the urgent demands for the project to be delivered in a short period of time have urged researchers to find a new scheme of programming in which they would be able to simulate or emulate the real life activities and projects using a computer and a procedural language. But such a scheme of programming was lengthy, tedious and costly. Therefore, it was necessary to find a specialized simulation software that would save the programmer's time and effort on the one hand and would save the client's money on the other. A number of simulation software were developed recently which contributed greatly to the solutions of the simulation problems. However, none of these languages possessed the completeness nor the independence of the use of other tools or procedural languages to compensate for their deficiencies.In this paper I have proposed a number of new ideas aimed to improve the simulation languages in general, and have implemented a number of these ideas in a software package. Chapter one describes the simulation model and the basic concepts of simulation. Chapter two describes briefly the advantages and disadvantages of using simulation software. Also it outlines the limitations of currently used simulation packages. Finally, it suggests new ideas and expectations of a complete simulation package. Chapter three describes the simulation package prototype S. E. S. and gives some implementations. Chapter four explains the basic differences between S. E. S. and SLAM II and shows areas for further research.
Department of Computer Science

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12

Fardipour, Parvin. "Computer modelling of the human cardiovascular system based on relational analysis". Thesis, City University London, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.328932.

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13

Berger, Ronald David. "Analysis of the cardiovascular control system using broad-band stimulation". Thesis, Massachusetts Institute of Technology, 1987. http://hdl.handle.net/1721.1/31010.

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14

Mukkamala, Ramakrishna 1971. "A forward model-based analysis of cardiovascular system identification methods". Thesis, Massachusetts Institute of Technology, 2000. http://hdl.handle.net/1721.1/17679.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2000.
Includes bibliographical references (p. 211-221).
Cardiovascular system identification is a potentially powerful approach for intelligent patient monitoring of cardiovascular function. Rather than merely recording hemodynamic signals, the signals are mathematically analyzed so as to provide a dynamical characterization of the physiologic mechanisms responsible for generating them. The fundamental aim of this thesis is to develop and evaluate cardiovascular system identification methods based on a test bed of data generated from a forward model of the cardiovascular system whose dynamical properties are known. To this end, we developed a computer model of the human cardiovascular system which includes a lumped parameter model of the heart and circulation and a model of the short-term cardiovascular regulatory system continuously disturbed by resting physiologic perturbations. The short-term regulatory system consists of arterial and cardiopulmonary baroreflex systems and a direct neural coupling mechanism between respiration and heart rate. The resting physiologic perturbations include respiratory activity and stochastic disturbances to total peripheral resistance (TPR) and heart rate representing, for example, autoregulation of local vascular beds and higher brain center activity. We demonstrated that this model emulates experimental data in terms of steady-state pulsatility, limiting static behavior, and low frequency hemodynamic variability. We first evaluated the performance of a previously developed cardiovascular system identification method against the forward model.
(cont.) The method involves the analysis of fluctuations in heart rate, arterial blood pressure (ABP), and instantaneous lung volume in order to characterize quantitatively important physiologic mechanisms including, for example, the heart rate baroreflex. From this analysis, we inferred that the cardiovascular system identification results derived from experimental data are likely to reflect the actual system dynamics of underlying physiologic mechanisms. We then introduced novel identification methods for quantifying TPR baroreflex dynamics from only fluctuations in cardiac output and ABP and for monitoring steady-state changes in TPR from only the ABP waveform. We demonstrated the efficacy f these identification methods with respect to forward model generated data and a preliminary set of experimental data. The results of this forward model-based analysis motivate the experimental validation of the cardiovascular system identification methods considered in this thesis.
by Ramakrishna Mukkamala.
Ph.D.

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15

Verma, Yukti. "Secure system simulation - Internet of Things". Thesis, California State University, Long Beach, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=10116148.

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Internet of Things (IoT) can be defined as a collection of smart devices interacting with each other unanimously to fulfill a common goal. The real world data collected from the Internet of Things can be made as an integral part of web known as Web of Things (WoT). With the help of Web of Things architecture, the users can leverage simple web mechanisms such as browsing, searching and caching to interact with the smart devices. This thesis aims to create an entire system simulating the Web of Things architecture including sensors, edge routers, web interfaces, endpoints to the IoT network and access control. Several technologies such as CoAP, 6LoWPAN, IEEE 802.15.4, contiki and DTLS have been evaluated before inclusion in the implementation. A complete web portal utilizing Californium framework and Role Based Access Control has been created for accessing and interacting with the sensors and their data. This thesis provides an end-to-end approach towards IoT device security by implementing Constrained Application Protocol (CoAP) over Datagram Transport Layer Security (DTLS) in the system. The performance of secured system is analyzed in a constrained environment based on which it is observed that DLTS implementation increases the RAM usage, code size, packet overhead and power consumption by a significant value. Finally, the future work that needs to considered in order to iterate towards better security is specified.

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16

Chadha, Vikrampal. "Simulation of large-scale system-level models". Thesis, This resource online, 1994. http://scholar.lib.vt.edu/theses/available/etd-12162009-020334/.

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17

Lai, Tsz-ming Terence y 黎子明. "Harmonic simulation of traction system". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2000. http://hub.hku.hk/bib/B3122281X.

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18

Martin, Timothy Patrick. "Flexible manufacturing system software development using simulation". Thesis, Virginia Polytechnic Institute and State University, 1985. http://hdl.handle.net/10919/101236.

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This paper presents a hierarchical modeling method that can be used to simulate a Flexible Manufacturing System (FMS) at all levels of detail. The method was developed specifically to aid the software development needed for the hierarchy of computers that are present in an FMS. The method was developed by modeling an existing FMS. The models developed of the existing FMS are described in detail to provide an example of how to model other FMSs. The basic building blocks needed for designing other FMSs with this modeling method are provided. The models were written in the SIMAN simulation language. SIMAN was found to be an easy language to use for the hierarchical modeling of FMSs.
M.S.

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19

Grygier, Paul Arthur. "Distributed Dynamic System Simulation Using a Computer Network". The Ohio State University, 1988. http://rave.ohiolink.edu/etdc/view?acc_num=osu1391676035.

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20

Mukkamala, Ramakrishna 1971. "Closed-loop system identification of cardiovascular control mechanisms in diabetic autonomic neuropathy". Thesis, Massachusetts Institute of Technology, 1995. http://hdl.handle.net/1721.1/36969.

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Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1995.
Includes bibliographical references (p. 92-95).
by Ramadrishna Mukkamala.
M.S.

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21

Suwarno, Neihl Omar 1963. "A computer based data acquisition and analysis system for a cardiovascular research laboratory". Thesis, The University of Arizona, 1989. http://hdl.handle.net/10150/558111.

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22

Jia, Yan. "Computer simulation of the lamprey spinal cord locomotor system". Thesis, University of Cambridge, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.610128.

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23

Arcot, Ramakant P. "Computer simulation of the Bristol compressor suspension system dynamics". Thesis, This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-09052009-040832/.

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24

Ma, Moses Hsingwen. "Efficient message-based system for concurrent simulation". Thesis, Massachusetts Institute of Technology, 1989. http://hdl.handle.net/1721.1/74802.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1989.
Title as it appeared in M.I.T Graduate List, February, 1989: Efficient message based systems for concurrent simulation.
Includes bibliographical references (leaves 267-269).
by Moses Hsingwen Ma.
Ph.D.

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25

Mak, Hing-Yin. "System dynamics and discrete event simulation modelling". Thesis, London School of Economics and Political Science (University of London), 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.263375.

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This thesis investigates the relationship between discrete event and system dynamics simulation modelling. Each modelling technique has its own strengths and limitations. The choice of using one particular modelling technique often depends on the preference and the knowledge of the modeller rather than on the nature of the problem. The basis of this research has been to address the problem from a different perspective. This has been to look at the nature of the problem first, and then determine the most appropriate modelling technique to apply. The basic method adopted was to compare, contrast and experiment with these two modelling techniques in order to determine a number of common and unrelated concepts between them. This investigation discovered that a system dynamics flow diagram could be used to represent an activity cycle diagram of a discrete event model. The converted flow diagram can provide a different viewpoint from the discrete event model due to the feedback characteristic of system dynamics. This research went on to develop a set of guidelines to convert an activity cycle diagram into a system dynamics flow diagram. Experimentation with many examples demonstrates that these conversion guidelines provide a consistent and systematic method for obtaining a system dynamics flow diagram. The final stage of this research was to develop a prototype computer system (SMCP) to demonstrate these guidelines. SMCP consists of two modules, the ACD module which allows the user to specify a discrete event model through textual descriptions, and the SD module which allows the user to build a system dynamics model by drawing symbols and using text inputs. In addition, SMCP allows users to convert an ACD to a system dynamics flow diagram quickly and easy, and also demonstrates the concept of data sharing.

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26

Tang, Xiaoxi. "Novel remote ECG real-time monitoring system /". View abstract or full-text, 2009. http://library.ust.hk/cgi/db/thesis.pl?CSED%202009%20TANG.

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27

Somaiya, Sandeep R. "SENATE : a software system for evaluation of simulation results /". Master's thesis, This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-03302010-020337/.

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28

Trivedi, Dyuti Kishorbhai. "Simulation of a Complete Cardiovascular Loop: Development of a Simulink Based Pressure-Flow Model to Obtain the Origin of the Electrical Impedance Cardiogram". Akron, OH : University of Akron, 2009. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=akron1232729044.

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Thesis (M.S.)--University of Akron, Dept. of Chemical and Biomedical Engineering, 2009.
"May, 2009." Title from electronic thesis title page (viewed 8/2/2009) Advisor, Bruce C. Taylor; Committee members, Daniel B. Sheffer, Dale H. Mugler; Department Chair, Daniel B. Sheffer; Dean of the College, George K. Haritos; Dean of the Graduate School, George R. Newkome. Includes bibliographical references.

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29

Krishnan, Krishna Kumar. "System based ladder logic simulation and debugging". Thesis, This resource online, 1991. http://scholar.lib.vt.edu/theses/available/etd-11072008-063418/.

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30

Wang, Ding Ph D. Massachusetts Institute of Technology. "Adaptive rapid environmental assessment system simulation framework". Thesis, Massachusetts Institute of Technology, 2005. http://hdl.handle.net/1721.1/33592.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Ocean Engineering; and, (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2005.
Includes bibliographical references (leaves 170-171).
Adaptive Rapid Environmental Assessment (AREA) is a new concept for minimizing the non model-based sonar performance prediction uncertainty and improving the model-based sonar performance by adaptive and rapid in situ measurement in the ocean environment. In this thesis, a possible structure of the AREA system has been developed; an AREA System Simulation Framework has been constructed using C++, which can simulate how AREA system will work and be utilized to determine the optimal or sub-optimal sampling strategies. A user's manual for the simulation framework, and specifications of all important C++ classes are included.
by Ding Wang.
S.M.

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31

Kasasbeh, Yousef Ahmed Mefleh. "A microcomputer-based visual system for maritime simulation". Thesis, University of Exeter, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.292944.

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32

Han, Jennifer Ching-Wen. "Using system dynamics in business simulation training games". Thesis, Massachusetts Institute of Technology, 1997. http://hdl.handle.net/1721.1/42762.

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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1997.
Includes bibliographical references (leaves 57-58).
by Jennifer Ching-Wen Han.
M.Eng.

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33

Gu, Yan. "ROSENET: a remote server-based network emulation system". Diss., Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/22662.

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Thesis (Ph. D.)--Computing, Georgia Institute of Technology, 2008.
Committee Chair: Fujimoto, Richard; Committee Member: Ammar, Mostafa; Committee Member: Bader, David; Committee Member: Goldsman, David; Committee Member: Park, Haesun; Committee Member: Riley, George.

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34

Patil, Ninad Mohan. "Artificial neural networks for cardiovascular risk, cardiovascular fitness and ankle-brachial index". Scholarly Commons, 2005. https://scholarlycommons.pacific.edu/uop_etds/616.

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Artificial Neural Networks are biologically inspired computational methodologies that can perfom multifactorial analyses. In recent years, they have been evaluated for medical decision support, with varying degrees of success. The preliminary part of my thesis deals with evaluating whether an Artificial Neural Network can be trained to approximate a cardiovascular risk stratification algorithm by Rifai et al. My subsequent work involves training the network on a population-based cross-sectional dataset with the objective of categorizing Ankle-Brachial Index and Maximal Oxygen Consumption. These are indicators of the severity of lower extremity atherosclerosis and the level of cardiovascular fitness respectively. NeuralSIM®, a commercially available Artificial Neural Network, was trained using C-reactive protein and Total Cholesterol/HDL Cholesterol ratio as input parameters, and the relative risk stratum for future myocardial infarctions or stroke as output. For the Ankle-Brachial Index and the cardiovascular fitness networks, data was obtained from the National Health and Nutrition Examination Survey. The network for cardiovascular fitness was compared with an algorithm published by Jackson et al. The network was able to approximate the cardiovascular risk stratification algorithm by Rifai et al closely with correlation coefficients of0.95 in men and 0.93 in women respectively. The network to screen for low cardiovascular fitness had a sensitivity of 83% and a specificity of 78%, with an overall accuracy of 81%. The Ankle-Brachial Index network demonstrated a high level of specificity (86.3%) for estimating abnonnal values but a very low sensitivity (30%). Artificial neural networks showed encouraging results for potential use as decision-support tools. One significant limitation is that the importance of individual parameters or the exact function cannot be ascertained easily. There is a need to address this issue in future software development.

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35

Yourkowski, Joel. "Computer simulation of an unmanned aerial vehicle electric propulsion system". Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1996. http://handle.dtic.mil/100.2/ADA307294.

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36

Roberts, Christopher C. "Plan-based simulation of malicious intruders on a computer system". Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1995. http://handle.dtic.mil/100.2/ADA297701.

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37

Weissmann, Eric. "Assessment of server location on system availability by computer simulation". Master's thesis, This resource online, 1994. http://scholar.lib.vt.edu/theses/available/etd-10242009-020123/.

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38

Obaidat, Mohammad Salameh. "A 68000 based modular multiprocessor system : design and simulation analysis /". The Ohio State University, 1986. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487266362336169.

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39

El-Hadad, Kamel Abdelsalam Mahmoud. "Expert systems and simulation : an investigation of an expert system to facilitate the development and use of system dynamic simulation models". Thesis, University of Kent, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.279602.

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40

Huang, GongWen 1948. "Computer aided model structuring in system design". Thesis, The University of Arizona, 1988. http://hdl.handle.net/10150/276903.

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As a CAD tool, the Computer Aided Model Structuring System (call MOSTS in the following text) for model structuring in system design and system simulation has been designed and implemented. First, this MOSTS allows system design experts to create and save System Data Bases (SDBs) for model structuring in system design and simulation. Then, these SDBs can be retrieved, modified, and finally used to structure system models by design engineers. The MOSTS pursues the model structuring process in such a way that the model structure having the best performance (according to the expert's knowledge and the design engineer's design criteria) will be generated first, and then the second best model, the third best model, and so on.

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41

Harrichunder, Rajen. "A learning support system for the Visual Simulation Environment". Master's thesis, This resource online, 1994. http://scholar.lib.vt.edu/theses/available/etd-02022010-020139/.

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42

Crouch, Ingrid W. M. "A knowledge-based simulation optimization system with machine learning". Diss., Virginia Tech, 1992. http://hdl.handle.net/10919/37245.

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43

Su, Ying-fung y 蘇盈峰. "Role of temporal texture in visual system: exploration with computer simulations". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2010. http://hub.hku.hk/bib/B43703768.

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44

Xiang, Luo. "A virtual Music fountain simulation based on particle system". Thesis, Högskolan i Gävle, Avdelningen för Industriell utveckling, IT och Samhällsbyggnad, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-13698.

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This report presents a real-time simulation of a music fountain which is simulated in three dimensions by a particle animation system. In this system, gravity and wind are factors that affect the locus movement of particles. Using kinematic equations, the dynamic behaviors of particles is modeled. A specific contribution of the work presented here is that parameters for the motion equation are estimated from sound playing in real-time which controls the dynamic behavior of animated fountain. An open source programming language called Processing is used to implement the environment. Results of the system are demonstrated in form of its graphical output and performance benchmarks from run-time evaluation. The author investigates the influence of the parameters of particle system and music attributes on the animation of the music fountain simulation. The size, number, color, texture and transparency of particles can influence the quality of music fountain simulation. Using FFT function to get music parameters is the best way to figure out differences between different music.

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45

Artica, I., G. Quispe y C. Raymundo-Ibañeez. "Ventilation System Simulation Model at a Mine". IOP Publishing Ltd, 2019. http://hdl.handle.net/10757/656302.

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This research project modeled and simulated a ventilation system at a Mining Concession, obtaining real-time information regarding the fans used to ventilate the mine. The simulation was developed using the VENTSIM 5 software, which also helped define the number of fans and the operating parameters required, field information, mine dimensions, the mining method, production, geothermal gradient, gas emission, air stream, and air pressure. In addition, the results from software operation revealed the need to open chimneys and use fans. Furthermore, the results also suggest that a specialist dedicated to ventilation and fan maintenance must be hired to formalize mining operations as per the Occupational Safety and Health Mining Regulations from Executive Action No. 024-2016-EM as this Mining Concession is currently operating without license.

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46

Deng, Yuwen. "Animated vehicle turning path simulation system on an Internet/Intranet browser". CSUSB ScholarWorks, 2002. https://scholarworks.lib.csusb.edu/etd-project/2091.

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The animated vehicle turning path simulation system on Internet/Intranet web browser presented in this project is intended to provide civil engineers with an easy-to-use, all functional simulation system that could help them with highway and street design.

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47

Salman, Huseyin Enes. "Investigation Of Fluid Structure Interaction In Cardiovascular System From Diagnostic And Pathological Perspective". Master's thesis, METU, 2012. http://etd.lib.metu.edu.tr/upload/12614388/index.pdf.

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Atherosclerosis is a disease of the cardiovascular system where a stenosis may develop in an artery which is an abnormal narrowing in the blood vessel that adversely affects the blood flow. Due to the constriction of the blood vessel, the flow is disturbed, forming a jet and recirculation downstream of the stenosis. Dynamic pressure fluctuations on the inner wall of the blood vessel leads to the vibration of the vessel structure and acoustic energy is propagated through the surrounding tissue that can be detected on the skin surface. Acoustic energy radiating from the interaction of blood flow and stenotic blood vessel carries valuable information from a diagnostic perspective. In this study, a constricted blood flow is modeled by using ADINA finite element analysis software together with the blood vessel in the form of a thin cylindrical shell with an idealized blunt constriction. The flow is considered as incompressible and Newtonian. Water properties at indoor temperature are used for the fluid model. The diameter of the modeled vessel is 6.4 mm with 87% area reduction at the throat of the stenosis. The flow is investigated for Reynolds numbers 1000 and 2000. The problem is handled in three parts which are rigid wall Computational Fluid Dynamics (CFD) solution, structural analysis of fluid filled cylindrical shell, and Fluid Structure Interaction (FSI) solutions of fluid flow and vessel structure. The pressure fluctuations and consequential vessel wall vibrations display broadband spectral content over a range of several hundred Hz with strong fluid-structural coupling. Maximum dynamic pressure and vibration amplitudes are observed around the reattachment point of the flow near the exit of the stenosis and this effect gradually decreases along downstream of flow. Results obtained by the numerical simulations are compared with relevant studies in the literature and it is concluded that ADINA can be used to investigate these types of problems involving high frequency pressure fluctuations of the fluid and the resulting vibratory motion of the surrounding blood vessel structure.

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48

夏炯 y Jiong James Xia. "Three-dimensional surgical planning and simulation system for orthognathic surgery in virtual reality environment". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1998. http://hub.hku.hk/bib/B3123950X.

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49

Mitchell, Eric J. (Eric Joseph) 1978. "Simulation of an optical network system for a space based high performance computer system". Thesis, Massachusetts Institute of Technology, 2002. http://hdl.handle.net/1721.1/16841.

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Thesis (M.Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2002.
Includes bibliographical references (leaf 57).
This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
An important future addition for a Space Based High Performance Computer System is a high-speed optical network for faster data transmission. The purpose of this project is to research and simulate next generation computing applications on high-speed optical networks. The research has been performed in the System Application context involving embedded high-performance computing applications and optical networking technology to guide future research and development of advanced optical devices. The research addresses advanced processing system issues in bandwidth, latency, protocol, topology, and fault tolerance in relation to high performance systems. The reference distributed computer, provided by BAE SYSTEMS in Nashua New Hampshire, consists of multiple processing nodes connected by a Myrinet copper network. The advanced embedded computing applications include Space-Based Radar Corner Turn processing, Synthetic Aperture Radar Back End processing, and Random Workload software models. Two Optical networks have been developed as part of this research to replace the reference Myrinet network, a Ring based network and a Star based network. Both networks employ redundancy to provide an alternate direct optical path between each pair of nodes. Of these networks the Ring design failed due to packet collisions and due to the need for a complex networking protocol. The Star Optical network design performed well in comparison to the reference network design. Overall, network latency was reduced and the internode data distribution speed was dramatically increased. Also, the memory usage for each of the three software models was analyzed and each has definite bound that will help future development. Although the results of this research are favorable, the eventual future design and implementation of a Space Based High Performance Computer System would benefit from additional research on a number of topics.
by Eric J. Mitchell.
M.Eng.

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50

Limsäter, Fredrik. "REACT - Crowd Simulation System for Visual Effects". Thesis, Linköping University, Department of Science and Technology, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-4737.

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By using existing knowledge from the game community, which have had a long experience from game artificial intelligence, and new research

from the field of artificial intelligence I have implemented REACT, a crowd simulation system for visual effects. REACT is based on high-level behaviour that uses an underlying layer of low-level behaviour. The high-level capabilities gives the digital character means to reasoning about how to achieve certain goals based on a knowledge base of rules and facts that are present in the virtual world. This gives the digital character a degree of autonomous intelligent behaviour.

REACT is designed to integrate directly into the 3D animation package Maya as a plug-in. This means that the animators can continue to animate their characters via their animation package of choice, rather than having to learn a new technology. In addition, many animators are already familiar with the workflow of Maya, so learning curves are reduced.

REACT is already in use in the visual effects industry where it has proven itself to be a worthy competitor to the existing systems on the market.

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Tesis sobre el tema "Cardiovascular system - Computer simulation"

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