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Full-Text Articles in Physical Sciences and Mathematics

Simulations In 3d Tactics, Interdiction And Multi-Agent Modelling, A. R. Green, I. C. Piper, Daniel Keep, C. J. Flaherty Dec 2012

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 Dec 2012

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 Dec 2012

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 Dec 2012

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 Dec 2012

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 Dec 2012

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 Dec 2012

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 …


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 Nov 2012

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 Nov 2012

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 Nov 2012

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 Nov 2012

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.


Human Motion Simulation And Action Corpus, Gang Zheng, Wanqing Li, Philip Ogunbona, Liju Dong, Igor Kharitonenko Sep 2012

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 …


Precis: A Design-Time Precision Analysis Tool, Mark L. Chang, Scott Hauck Jul 2012

Precis: A Design-Time Precision Analysis Tool, Mark L. Chang, Scott Hauck

Mark L. Chang

Currently, few tools exist to aid the FPGA developer in translating an algorithm designed for a general-purpose-processor into one that is precision-optimized for FPGAs. This task requires extensive knowledge of both the algorithm and the target hardware. We present a design-time tool, Precis, which assists the developer in analyzing the precision requirements of algorithms specified in MATLAB. Through the combined use of simulation, user input, and program analysis, we demonstrate a methodology for precision analysis that can aid the developer in focusing their manual precision optimization efforts.


Simulating Non-Normal Distributions With Specified L-Moments And L-Correlations, Todd C. Headrick, Mohan D. Pant May 2012

Simulating Non-Normal Distributions With Specified L-Moments And L-Correlations, Todd C. Headrick, Mohan D. Pant

Mohan Dev Pant

This paper derives a procedure for simulating continuous non-normal distributions with specified L-moments and L-correlations in the context of power method polynomials of order three. It is demonstrated that the proposed procedure has computational advantages over the traditional product-moment procedure in terms of solving for intermediate correlations. Simulation results also demonstrate that the proposed L-moment-based procedure is an attractive alternative to the traditional procedure when distributions with more severe departures from normality are considered. Specifically, estimates of L-skew and L-kurtosis are superior to the conventional estimates of skew and kurtosis in terms of both relative bias and relative standard error. …


Parallel Diffusion-Limited Aggregation, H Kaufman, A Vespignani, B B. Mandelbrot, L Woog Apr 2012

Parallel Diffusion-Limited Aggregation, H Kaufman, A Vespignani, B B. Mandelbrot, L Woog

Alessandro Vespignani

We present methods for simulating very large diffusion-limited aggregation (DLA) clusters using parallel processing (PDLA). With our techniques, we have been able to simulate clusters of up to 130 million particles. The time required for generating a 100 million particle PDLA is approximately 13 h. The fractal behavior of these ''parallel'' clusters changes from a multiparticle aggregation dynamics to the usual DLA dynamics. The transition is described by simple scaling assumptions that define a characteristic cluster size separating the two dynamical regimes. We also use DLA clusters as seeds for parallel processing. In this case, the transient regime disappears and …


Sample Size Calculations For Roc Studies: Parametric Robustness And Bayesian Nonparametrics, Dunlei Cheng, Adam J. Branscum, Wesley O. Johnson Jan 2012

Sample Size Calculations For Roc Studies: Parametric Robustness And Bayesian Nonparametrics, Dunlei Cheng, Adam J. Branscum, Wesley O. Johnson

Dunlei Cheng

Methods for sample size calculations in ROC studies often assume independent normal distributions for test scores among the diseased and non-diseased populations. We consider sample size requirements under the default two-group normal model when the data distribution for the diseased population is either skewed or multimodal. For these two common scenarios we investigate the potential for robustness of calculated sample sizes under the mis-specified normal model and we compare to sample sizes calculated under a more flexible nonparametric Dirichlet process mixture model. We also highlight the utility of flexible models for ROC data analysis and their importance to study design. …


Simulating Non-Normal Distributions With Specified L-Moments And L-Correlations, Todd C. Headrick, Mohan D. Pant Jan 2012

Simulating Non-Normal Distributions With Specified L-Moments And L-Correlations, Todd C. Headrick, Mohan D. Pant

Todd Christopher Headrick

This paper derives a procedure for simulating continuous non-normal distributions with specified L-moments and L-correlations in the context of power method polynomials of order three. It is demonstrated that the proposed procedure has computational advantages over the traditional product-moment procedure in terms of solving for intermediate correlations. Simulation results also demonstrate that the proposed L-moment-based procedure is an attractive alternative to the traditional procedure when distributions with more severe departures from normality are considered. Specifically, estimates of L-skew and L-kurtosis are superior to the conventional estimates of skew and kurtosis in terms of both relative bias and relative standard error. …


Data Envelopment Analysis In The Presence Of Measurement Error: Case Study From The National Database Of Nursing Quality Indicators (Ndnqi), Byron J. Gajewski, Robert Lee, Nancy Dunton Jan 2012

Data Envelopment Analysis In The Presence Of Measurement Error: Case Study From The National Database Of Nursing Quality Indicators (Ndnqi), Byron J. Gajewski, Robert Lee, Nancy Dunton

Byron J Gajewski

Data envelopment analysis (DEA) is the most commonly used approach for evaluating healthcare efficiency [B. Hollingsworth, The measurement of efficiency and productivity of health care delivery. Health Economics 17(10) (2008), pp. 1107–1128], but a long-standing concern is that DEA assumes that data are measured without error. This is quite unlikely, and DEA and other efficiency analysis techniques may yield biased efficiency estimates if it is not realized [B.J. Gajewski, R. Lee, M. Bott, U. Piamjariyakul, and R.L. Taunton, On estimating the distribution of data envelopment analysis efficiency scores: an application to nursing homes’ care planning process. Journal of Applied Statistics …