Physical Sciences and Mathematics Commons^™

The Evolution Of Modular Product Architectures And The Emergence Of Platform Ecosystems, C. Jason Woodard, Eric K. Clemons

C. Jason Woodard

No abstract provided.

Stochastic Modeling And Time-To-Event Analysis Of Voip Traffic, Imad Al Ajarmeh

College of Computing and Digital Media Dissertations

Voice over IP (VoIP) systems are gaining increased popularity due to the cost effectiveness, ease of management, and enhanced features and capabilities. Both enterprises and carriers are deploying VoIP systems to replace their TDM-based legacy voice networks. However, the lack of engineering models for VoIP systems has been realized by many researchers, especially for large-scale networks. The purpose of traffic engineering is to minimize call blocking probability and maximize resource utilization. The current traffic engineering models are inherited from the legacy PSTN world, and these models fall short from capturing the characteristics of new traffic patterns. The objective of this …

Optimized Simulation Of Granular Materials, Seth R. Holladay

Theses and Dissertations

Visual effects for film and animation often require simulated granular materials, such as sand, wheat, or dirt, to meet a director's needs. Simulating granular materials can be time consuming, in both computation and labor, as these particulate materials have complex behavior and an enormous amount of small-scale detail. Furthermore, a single cubic meter of granular material, where each grain is a cubic millimeter, would contain a billion granules, and simulating all such interacting granules would take an impractical amount of time for productions. This calls for a simplified model for granular materials that retains high surface detail and granular behavior …

A Compiler-Based Framework For Automatic Extraction Of Program Skeletons For Exascale Hardware/Software Co-Design, Amruth Rudraiah Dakshinamurthy

Electronic Theses and Dissertations

The design of high-performance computing architectures requires performance analysis of largescale parallel applications to derive various parameters concerning hardware design and software development. The process of performance analysis and benchmarking an application can be done in several ways with varying degrees of fidelity. One of the most cost-effective ways is to do a coarse-grained study of large-scale parallel applications through the use of program skeletons. The concept of a “program skeleton” that we discuss in this paper is an abstracted program that is derived from a larger program where source code that is determined to be irrelevant is removed for …

Special Issue: M&S Optimization Applications In Industry And Engineering, Part 2, Rafael Diaz, Andreas Tolk

VMASC Publications

(First paragraph) Welcome to the second part of the special issue on modeling and simulation (M&S) optimization applications in industry and engineering. This issue incorporates additional publications that reflect various applications and areas of simulation and optimization.

Mesoscopic Methods In Engineering And Science, Jos Derksen, Dmitry Eskin, Li-Shi Luo, Manfred Krafczyk

Mathematics & Statistics Faculty Publications

(First paragraph) Matter, conceptually classified into fluids and solids, can be completely described by the microscopic physics of its constituent atoms or molecules. However, for most engineering applications a macroscopic or continuum description has usually been sufficient, because of the large disparity between the spatial and temporal scales relevant to these applications and the scales of the underlying molecular dynamics. In this case, the microscopic physics merely determines material properties such as the viscosity of a fluid or the elastic constants of a solid. These material properties cannot be derived within the macroscopic framework, but the qualitative nature of the …

Collective Librations Of Water Molecules In The Crystal Lattice Of Rubidium Bromide: Experiment And Simulation, L M. Lepodise, J Horvat, Roger A. Lewis

Australian Institute for Innovative Materials - Papers

Terahertz spectroscopy of RbBr reveals four prominent absorption lines at room temperature and a further 15 lines at 10 K. Via density-functional-theory (DFT) numerical modelling using the PBE0 hybrid GGA functional, all the absorptions are identified as correlated librations of water molecules in the RbBr lattice. Each libration mode is a combination of rocking, wagging and twisting motions of the water molecules. The number of libration lines and numerical modelling show that the C2v symmetry of water in RbBr is broken. Our modelling shows that the distribution of libration amplitudes and phases for different water molecules in the RbBr unit …

Simulation Of Transient Processes On Overvoltage In Electric Transmission Lines Using Atp-Emtp, Ahmet Nayi̇r

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, the mathematical modeling and simulation of electromagnetic transient processes is considered, which is of vital importance for examining the overvoltage phenomenon of power transmission systems. In the mathematical models of the AC power transmission systems that contain a power source, the power transformer, transmission line, and power autotransformer block are presented. The mathematical model of each system component is obtained based on the branch voltages, flux linkages, and branch voltages of the magnetic circuits individually. As for the simulation, an alternative transient program (ATP) environment is used to model the electric power system's elements. One of the …

Packet Coalescing And Server Substitution For Energy-Proportional Operation Of Network Links And Data Servers, Mehrgan Mostowfi

USF Tampa Graduate Theses and Dissertations

Electricity generation for Information and Communications Technology (ICT) contributes over 2% of the human-generated CO2 to the atmosphere. Energy costs are rapidly becoming the major operational expense for ICT and may soon dwarf capital expenses as software and hardware continue to drop in price. In this dissertation, three new approaches to achieving energy-proportional operation of network links and data servers are explored.

Ethernet is the dominant wireline communications technology for Internet connectivity. IEEE 802.3az Energy Efficient Ethernet (EEE) describes a Low Power Idle (LPI) mechanism for allowing Ethernet links to sleep. A method of coalescing packets to consolidate link idle …

Electric Field Standing Wave Effects In Ft-Ir Transflection Spectra Of Biological Tissue Sections: Simulated Models Of Experimental Variability, Tomasz P. Wrobel, Barbara Wajnchold, Hugh Byrne, Malgorzata Baranska

Articles

The so-called electric field standing wave effect (EFSW) has recently been demonstrated to significantly distort FT-IR spectra acquired in a transflection mode, both experimentally and in simulated models, bringing into question the appropriateness of the technique for sample characterization, particularly in the field of spectroscopy of biological materials. The predicted effects are most notable in the regime where the sample thickness is comparable to the source wavelength. In this work, the model is extended to sample thicknesses more representative of biological tissue sections and to include typical experimental factors which are demonstrated to reduce the predicted effects. These include integration …

Applications Of Agent Based Approaches In Business: A Three Essay Dissertation, Shankar Prawesh

USF Tampa Graduate Theses and Dissertations

The goal of this dissertation is to investigate the enabling role that agent based simulation plays in business and policy. The aforementioned issue has been addressed in this dissertation through three distinct, but related essays. The first essay is a literature review of different research applications of agent based simulation in various business disciplines, such as finance, economics, information systems, management, marketing and accounting. Various agent based simulation tools to develop computational models are discussed. The second essay uses an agent-based simulation approach to study important properties of the widely used most popular news recommender systems (NRS). This essay highlights …

Simulation Of A Large Electric Distribution System Having Intensive Harmonics In The Industrial Zone Of Konya, Hasan Eroğlu, Musa Aydin

Turkish Journal of Electrical Engineering and Computer Sciences

In this study, measurements were taken at different points of a sample distribution system in order to analyze the levels of harmonics that appear as a day-to-day increasing problem in electrical distribution systems. According to the measurement values, the dominant harmonics have been determined and an electrical model of the system has been prepared using the SimPowerSystems toolbox from MATLAB and Simulink. The accuracy of the electrical model has been verified by the measurement and simulation values. In addition, the transformer connection types' and impedances' simulations have been presented to understand and solve the harmonic problems in electrical distribution systems. …

Simulation Of Discrete Electromagnetic Propagation Model For Atmospheric Effects On Mobile Communication, Şaban Seli̇m Şeker, Fulya Kunter

Turkish Journal of Electrical Engineering and Computer Sciences

Wireless communication has become an important part of our lives, and atmospheric effects are one of the ultimate factors affecting quality of communication and satellite systems. In this study the attenuation in mobile communication due to atmospheric events like snow and rain is simulated using the discrete propagation model. In this work, spherical raindrop and oblate spheroid raindrop modeling are used. To check the validity of simulations, the commonly used and accepted ITU-R rain model is used. Oblate spheroid raindrop modeling produces results that are more compatible with ITU-R results, especially at frequencies higher than 50 GHz. At lower frequencies, …

Simulations In 3d Tactics, Interdiction And Multi-Agent Modelling, A. R. Green, I. C. Piper, Daniel Keep, C. J. Flaherty

Dr Ian Piper

The analysis of vulnerabilities in large complex spaces is fundamentally problematic. The lack of capacity to generate a threat assessment merely exacerbates this problem. Lacking as well, in current literature is a developed methodology. To overcome this problem, we propose an approach using multi-agent modelling, which is also melded with three dimensional (3D) tactical understandings. Our approach builds on a microsimulation decision support tool, which was developed for a behavioural simulation of CBRN events. Microsimulation is based on the individual; who as an individual has a number of attributes, and which are stochastic (when repeated within an attribute). This approach …

Human Motion Simulation And Action Corpus, Gang Zheng, Wanqing Li, Philip Ogunbona, Liju Dong, Igor Kharitonenko

Associate Professor Wanqing Li

Acquisition of large scale good quality training samples is becoming a major issue in machine learning based human motion analysis. This paper presents a method to simulate continuous gross human body motion with the intention to establish a human motion corpus for learning and recognition. The simulation is achieved by a temporal-spatialtemporal decomposition of human motion into actions, joint actions and actionlets based on the human kinematic model. The actionlet models the primitive moving phase of a joint and represents the muscle movement governed by kinesiological principles. Joint actions and body actions are constructed from actionlets through constrained concatenation and …

Simulation Of Human Motion For Learning And Recognition, Gang Zheng, Wanqing Li, Philip Ogunbona, Liju Dong, Igor Kharitonenko

Associate Professor Wanqing Li

Acquisition of good quality training samples is becoming a major issue in machine learning based human motion analysis. This paper presents a method to simulate human body motion with the intention to establish a human motion corpus for learning and recognition. The simulation is achieved by a unique temporal-spatial-temporal decomposition of human body motion into actions, joint actions and actionlets based on the human kinematic model. The actionlet models the primitive moving phase of a joint and can be simulated based on the kinesiological study. A joint action is formed by proper concatenation of actionlets and an action is a …

Human Motion Simulation And Action Corpus, Gang Zheng, Wanqing Li, Philip Ogunbona, Liju Dong, Igor Kharitonenko

Dr Igor Kharitonenko

Acquisition of large scale good quality training samples is becoming a major issue in machine learning based human motion analysis. This paper presents a method to simulate continuous gross human body motion with the intention to establish a human motion corpus for learning and recognition. The simulation is achieved by a temporal-spatialtemporal decomposition of human motion into actions, joint actions and actionlets based on the human kinematic model. The actionlet models the primitive moving phase of a joint and represents the muscle movement governed by kinesiological principles. Joint actions and body actions are constructed from actionlets through constrained concatenation and …

Modelling And Simulation Of An Adaptive Neuro-Fuzzy Inference System (Anfis) For Mobile Learning, Ahmed Al-Hmouz, Jun Shen, Rami Al-Hmouz, Jun Yan

Dr Jun Yan

With recent advances in mobile learning (m-learning), it is becoming possible for learning activities to occur everywhere. The learner model presented in our earlier work was partitioned into smaller elements in the form of learner profiles, which collectively represent the entire learning process. This paper presents an Adaptive Neuro-Fuzzy Inference System (ANFIS) for delivering adapted learning content to mobile learners. The ANFIS model was designed using trial and error based on various experiments. This study was conducted to illustrate that ANFIS is effective with hybrid learning, for the adaptation of learning content according to learners' needs. Study results show that …

Design And Simulation Of A Ds-Th-Uwb System Using Simulink/Matlab For First Arriving Rays In A Non Line Of Sight Wireless Scenario, Peter Vial

Dr Peter Vial

An Ultra Wideband system was developed using Simulink in previous work. Using this developed model for Ultra Wideband (UWB) Pulse Position Modulation (PPM) within Simulink, we apply Direct Sequence Walsh codes across Time Hopping Patterns to smooth out the spectral characteristics with Pulse Position Modulation. A non-line of sight Saleh-Valenzuela (SV) model is used to characterize the wireless channel. The system is described and results are presented for the scenario where the first arriving rays are used to detect the transmitted message. For this non-optimum technique (in that for non line of sight the strongest signal rays are available after …

Modelling And Simulation Of An Adaptive Neuro-Fuzzy Inference System (Anfis) For Mobile Learning, Ahmed Al-Hmouz, Jun Shen, Rami Al-Hmouz, Jun Yan

Dr Jun Shen

With recent advances in mobile learning (m-learning), it is becoming possible for learning activities to occur everywhere. The learner model presented in our earlier work was partitioned into smaller elements in the form of learner profiles, which collectively represent the entire learning process. This paper presents an Adaptive Neuro-Fuzzy Inference System (ANFIS) for delivering adapted learning content to mobile learners. The ANFIS model was designed using trial and error based on various experiments. This study was conducted to illustrate that ANFIS is effective with hybrid learning, for the adaptation of learning content according to learners' needs. Study results show that …

Secure Key Deployment And Exchange Protocol For Manet Information Management, Brian Cusack, Alastair Nisbet

Australian Digital Forensics Conference

Secure Key Deployment and Exchange Protocol (SKYE) is an innovative encryption Key Management Scheme (KMS) based on a combination of features from recent protocols combined with new features for Mobile Ad Hoc Networks (MANETs). The design focuses on a truly ad hoc networking environment where geographical size of the network, numbers of network members and mobility of the members is all unknown before deployment. This paper describes the process of development of the protocol and the application to system design to assure information security and potential evidential retention for forensic purposes. Threshold encryption key management is utilized and simulation results …

On Decision Making: Bayesian And Stochastic Optimization Approaches, Yang Shen

Masters Theses

Decision analysis provides a framework for searching an optimal solution under uncertainties and potential risks. This thesis focuses on two problems arising in transportation engineering and computer sciences, respectively.

First, it is considered a centralized controller which imposes actions on a number of interacting subsystems. Employing an appropriate Markov Decision Process framework, we establish that the Pareto optimal solution of each subsystem will be optimal for the entire system. Synthetic data have been taken into account for verifying this claim.

Next, we focus on a supercomputing problem utilizing a hierarchical Bayesian model. We estimate an optimal solution in order to …

Simamph: An Agent-Based Simulation Model For Exploring The Use Of Psychostimulants And Related Harm Amongst Young Australians, Pascal Perez, Anne Dray, David Moore, Paul Dietze, Gabriele Bammer, Rebecca Jenkinson, Christine Siokou, Rachael Green, Susan Hudson, Lisa Maher

Professor Pascal Perez

Background: Computer simulations provide a useful tool for bringing together diverse sources of information in order to increase understanding of the complex aetiology of drug use and related harm, and to inform the development of effective policies. In this paper, we describe SimAmph, an agent-based simulation model for exploring how individual perceptions, peer influences and subcultural settings shape the use of psychostimulants and related harm amongst young Australians. Methods: We present the conceptual architecture underpinning SimAmph, the assumptions we made in building it, the outcomes of sensitivity analysis of key model parameters and the results obtained when we modelled a …

An Ontology-Based Simulation Model Exploring The Social Contexts Of Psychostimulant Use Among Young Australians, Pascal Perez, Anne Dray, Paul Dietze, David Moore, Rebecca Jenkinson, Christine Siokou, Rachael Green, Susan L. Hudson, Lisa Maher, Gabriele Bammer

Professor Pascal Perez

The principal anthropogenic factors driving reef degradation have been known for years, if not decades. Overfishing, sedimentation and nutrient loads are just some of the key impacts of human activities in and around reef communities. Therefore, the future of reefs does not rely on generating new knowledge, but rather on implementing and integrating the knowledge we already have. This will require creating effective links between researchers, managers and communities to promote mutual learning, negotiation and collaborative action for reef management. Combining agent-based models and role-play games, through a technique known as Companion Modelling (ComMod), creates a dynamic and interactive setting …

Are Drug Detection Dogs And Mass-Media Campaigns Likely To Be Effective Policy Responses To Psychostimulant Use And Related Harm? Results From An Agent-Based Simulation Model, David Moore, Lisa Maher, Christine Siokou, Rachael Green, Anne Dray, Rebecca Jenkinson, Susan Hudson, Gabriele Bammer, Pascal Perez, Paul Dietze

Professor Pascal Perez

Background Agent-based simulation models can be used to explore the impact of policy and practice on drug use and related consequences. In a linked paper (Perez et al., 2011), we described SimAmph, an agent-based simulation model for exploring the use of psychostimulants and related harm amongst young Australians. Methods In this paper, we use the model to simulate the impact of two policy scenarios on engagement in drug use and experience of drug-related harm: (i) the use of passive-alert detection (PAD) dogs by police at public venues and (ii) the introduction of a mass-media drug prevention campaign. Results The findings …

A Simulation Study On The Energy Efficiency Of Pure And Slotted Aloha Based Rfid Tag Reading Protocols, Alejandro Ruiz-Rivera, Dheeraj Klair, Kwan-Wu Chin

Associate Professor Kwan-Wu Chin

This paper studies the energy efficiency of twelve Pure and Slotted Aloha tag reading protocol variants via simulation. We compare their energy consumption in three collision resolution phases: 1) success, 2) collision, and 3) idle. Our extensive simulation results show that Pure Aloha with fast mode and muting has the lowest energy consumption, and hence is most suited for deployment in energy-constrained environments.

Testing The Population Coefficient Of Variation, Shipra Banik, B. M. Golam Kibria, Dinesh Sharma

Journal of Modern Applied Statistical Methods

The coefficient of variation (CV), which is used in many scientific areas, measures the variability of a population relative to its mean and standard deviation. Several methods exist for testing the population CV. This article compares a proposed bootstrap method to existing methods. A simulation study was conducted under both symmetric and skewed distributions to compare the performance of test statistics with respect to empirical size and power. Results indicate that some of the proposed methods are useful and can be recommended to practitioners.

A New Random Walk Simulation Model For Study Of Diffusion Behavior Of Single Particle Within Two-Dimensional Space, Jianwei Zhao, Lili Chen, Yingqiang Fu, Shaohong Li, Tiannan Chen, Shijie Zhang

Journal of Electrochemistry

Research on diffusion behaviors is of significant value in that it is closely related to transport phenomena in micro-chemistry. However, the effects of variables on diffusion are still unclear. Here, we developed and programmed a simulation methodology along with data analysis, which was capable to simulate the diffusion of a particle within twodimensional heterogeneous space in large timescale; the effects of periodically arranged impenetrable barriers of specific shape and lateral drifting velocity on diffusion behavior were studied. As well as standard mean square displacement analysis, a new method, the appearance probability distribution method, was introduced, which revealed whether the particle …

Human Motion Simulation And Action Corpus, Gang Zheng, Wanqing Li, Philip Ogunbona, Liju Dong, Igor Kharitonenko

Professor Philip Ogunbona

Acquisition of large scale good quality training samples is becoming a major issue in machine learning based human motion analysis. This paper presents a method to simulate continuous gross human body motion with the intention to establish a human motion corpus for learning and recognition. The simulation is achieved by a temporal-spatialtemporal decomposition of human motion into actions, joint actions and actionlets based on the human kinematic model. The actionlet models the primitive moving phase of a joint and represents the muscle movement governed by kinesiological principles. Joint actions and body actions are constructed from actionlets through constrained concatenation and …

A Computational Analysis Of Bundle Trading Markets Design For Distributed Resource Allocation, Zhiling Guo, Gary J. Koehler, Andrew B. Whinston

Research Collection School Of Computing and Information Systems

Online auction markets play increasingly important roles for resource allocations in distributed systems. This paper builds upon a market-based framework presented by Guo et al. (Guo, Z., G. J. Koehler, A. B. Whinston. 2007. A market-based optimization algorithm for distributed systems. Management Sci. 53(8) 1345–1458), where a distributed system optimization problem is solved by self-interested agents iteratively trading bundled resources in a double auction market run by a dealer. We extend this approach to a dynamic, asynchronous Internet market environment and investigate how various market design factors including dealer inventory policies, market communication patterns, and agent learning strategies affect the …