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G∀ST is a fully automatic test system. Given a logical property, stated as a function, it is able to generate appropriate test values, to execute tests with these values, and to evaluate the results of these tests. Many reactive systems, like automata and protocols, however, are specified by a model rather than in logic. There exist tools that are able to test software described by such a model-based specification, but these tools have limited capabilities to generate test data involving data types. Moreover, in these tools it is hard or even impossible to state properties of these values in logic. In this paper we introduce some extensions of G∀ST to combine the best of logic and model based testing. The integration of model based testing and testing based on logical properties in a single automated system is the contribution of this paper. The system consists only of a small library rather than a huge stand-alone system. [ABSTRACT FROM AUTHOR]

Object-oriented (OO) methods become more and more important in order to meet scientific computing challenges, such as the treatment of coupled non-linear multi-field problems with extremely high resolutions. This two-part paper introduces an object-oriented concept for numerical modelling multi-process systems in porous media (Part 1). The C++ implementation of the OO design for process objects (PCS) as a class is described and illustrated with several applications. Due to the importance of the encapsulation of processes as individual PCS objects we denote our concept as an process-oriented approach. The presented examples (Part 2) are dealing with thermal (T), hydraulic (H), mechanical (M) and componental processes (C) in bentonite materials, which are used as buffer material for the isolation of hazardous waste in geologic barriers. In particular, we are interested in coupling phenomena such as thermally induced desaturation, non-isothermal consolidation, swelling/shrinking phenomena as well as in a better understanding of the coupled, non-linear THM system. Part 1 of this paper is about design and implementation of processes in an object-oriented way. Here we give numerical examples to show the variety of problems which can be treated based on the process-oriented approach. [ABSTRACT FROM AUTHOR]

IEEE802.16 is the standard defining the Worldwide Interoperability for Microwave Access (WiMAX) for Metropolitan Area Network (MAN). WiMAX has recently being considered by Internet Service Providers (ISPs) as an attractive alternative to leasing lines from current ISPs or the deployment of new fiber networks. This is mainly the case since WiMAX is more flexible and much cheaper than other possible solutions. Our focus in this paper is on mobile WiMAX i.e. IEEE802.16e designed to provide broadband wireless access for mobile users. In this paper we have designed various scenarios using the Qualnet simulation package to evaluate the performance of WiMAX in delivering traffic under different operational conditions for a point to multi point configuration. The results showed how different factors such as load and mobility might affect the performance of WiMAX in a single cell environment. End to end delay, delay jitter and throughput were considered as the performance measures in this study. [ABSTRACT FROM AUTHOR]

This paper presents and investigates a dynamic buffer management scheme for QoS control of multimedia services in a 3.5G wireless system i.e. the High Speed Downlink Packet Access (HSDPA). HSDPA was introduced to enhance UMTS for high-speed packet switched services. With HSDPA, packet scheduling and HARQ mechanisms in the base station require data buffering at the air interface thus introducing a potential bottleneck to end-to-end communication. Hence, for multimedia services with multiplexed parallel diverse flows such as video and data in the same end-user session, buffer management schemes in the base station are essential to support end-to-end QoS provision. We propose a dynamic buffer management scheme for HSDPA multimedia sessions with aggregated real-time and non real-time flows in the paper. The end-to-end performance impact of the scheme is evaluated with an example multimedia session comprising a real-time streaming flow concurrent with TCP-based non real-time flow via extensive HSDPA simulations. Results demonstrate that the scheme can guarantee the end-to-end QoS of the real-time streaming flow, whilst simultaneously protecting non real-time flow from starvation resulting in improved end-to-end throughput performance. [ABSTRACT FROM AUTHOR]

This paper presents two simulation models for two variants of a large chipper drive used in a paper mill. If a slip ring induction motor is used, the impact of a rotor circuit rheostat with respect to starting behavior and heavy duty load impulses can be examined. Furthermore a speed controlled squirrel cage induction machine will be investigated. The modeling language for both drives is Modelica. The simulation results for both drives are compared and discussed. [ABSTRACT FROM AUTHOR]

Biometric recognition and authentication based on face recognitions can actually be used in many real-time applications such as surveillance, security systems, access control, and much more. For these purposes systems have to grant a fast computational speed but also robustness to illumination and facial expressions variations. In this paper we propose a very fast image pre-processing by the introduction of a linearly shaded elliptical mask centered over the faces. Simulation results, over the AR Database, show that the proposed method leads to a significant performance improvement in identification, using both eigenfaces and DCT with Nearest Neighbour and RBF Neural Network, without modifying the global computational weight. [ABSTRACT FROM AUTHOR]

This paper studies the modified sensitivity analysis applied into an elastic-plastic finite element analysis of a 3D blank design in sheet metal forming. Originally the sensitivity method has successfully been applied to several arbitrary shapes. In the present paper the sensitivity coefficients are not considered constant during the analysis. The presented approach computes the new coefficients from the two last iterations. This method can produce an initial blank boundary shape that has any arbitrary flange shape. A cup with uniform flange has been studied in detail and results show a faster solution convergence than the published sensitivity method. Experimental tests were conducted to compare with the numerical simulations. The optimum blank shape obtained from the numerical simulations was used during the experimental trials. The results of experimental tests for both square and optimal blank are presented here. [ABSTRACT FROM AUTHOR]

This paper presents the initial results of a study aimed at improving the method by which the vibrations produced by transport vehicles are characterised and simulated. More specifically, this paper focuses on the rigid body vibrations generated by road transport vehicles in the context of distribution of packaged goods and produce. The research uses a variety of vibration data, collected from various vehicle types and routes in Spain and Australia with high-capacity vibration recorders. Vehicles used range from small transport vehicles to large truck-trailers with both airbags and steel spring suspensions while the routes travelled include suburban streets, main roads and motorways. The paper discusses the significance and limitations of the average power spectral density (PSD) and explains why the average PSD is not always adequate as the sole descriptor of road vehicle vibrations as the process generally tends to be non-stationary and non-Gaussian. The paper adopts an alternative analysis method, based on the statistical distribution of the moving root-mean-square (RMS) vibrations, as a supplementary indicator of overall ride quality. The measured data was used to compute the statistical distribution of each vibration record, the shape of which was compared for the entire set of records. The suitability of various mathematical models, based on the Weibull and Rayleigh distributions were investigated for describing the probability distribution function (PDF) of road vehicle vibration RMS time history. The paper proposes a single mathematical model that can accurately describe the statistical character of the random vibrations generated by road vehicles in general. It shows that the model can also effectively describe the statistical parameters of the process namely the mean, median, standard deviation, skewness and kurtosis. [ABSTRACT FROM AUTHOR]

This paper presents an approach to agent's action selection strategy called stepwise case-based reasoning (SCBR). In this paper an agent that roams in 3D synthetic world is called an SCBR agent. An SCBR agent is an entity that selects the next action based on previous interaction experience and on simulated vision. An SCBR agent's interaction experience is represented in the form of two different types of cases: plan cases and contextual cases. [ABSTRACT FROM AUTHOR]

In this paper, multi-objective genetic algorithm (MOGA) is proposed to combine the advantages of fixed-structure robust H∞ control and the model reference control. Robust controller designed by the conventional H∞ optimal control is complicated and high order. This problem can be solved by using a genetic algorithm to search the optimal parameters in a specified structure robust controller. The fitness function for this technique is based on the concept of robust control, which normally is specified in frequency domain. However, in many cases, time domain specifications such as overshoot, undershoot, rise time are also important. To enhance the GA based robust control technique, in this paper, the cost function of model reference control is added into the GA process to incorporate the time domain specification. By the proposed approach, the robustness, frequency domain and time domain specifications can be achieved simultaneously. Simulation results in a servo system show the effectiveness of the proposed technique. [ABSTRACT FROM AUTHOR]

This paper discusses a Web-based parallel and distributed computing platform that supports multiple users to run experiments and optimizations with different deterministic/stochastic simulation systems. The platform is designed to be multi-tier client/server based in which all complex components, including various metaheuristic search algorithms, neural network based metamodels, deterministic/stochastic simulation systems and the corresponding database management system are integrated in a parallel and distributed platform and made available for general users to easily access, anytime, anywhere, through Web Services technology. In addition to revealing the system architecture of this platform, this paper also addresses the importance of logging simulation experiment results and optimization trajectories into the database to support advanced features like metamodelling, dynamically changing metaheuristic algorithms and fault tolerance within an integrated framework. Performance improvement on simulation optimization processes using these integrated features are illustrated with both multi-objective and single-objective optimization problems taken from industry. [ABSTRACT FROM AUTHOR]

In this paper, multi-objective genetic algorithm (MOGA) is proposed to combine the advantages of fixed-structure robust H∞ control and the model reference control. Robust controller designed by the conventional H∞ optimal control is complicated and high order. This problem can be solved by using a genetic algorithm to search the optimal parameters in a specified structure robust controller. The fitness function for this technique is based on the concept of robust control, which normally is specified in frequency domain. However, in many cases, time domain specifications such as overshoot, undershoot, rise time are also important. To enhance the GA based robust control technique, in this paper, the cost function of model reference control is added into the GA process to incorporate the time domain specification. By the proposed approach, the robustness, frequency domain and time domain specifications can be achieved simultaneously. Simulation results in a servo system show the effectiveness of the proposed technique. [ABSTRACT FROM AUTHOR]

This paper introduces methods, based on decomposable random combinatorial analysis, to model a large number of interacting agents. This paper also discusses a largely ignored possibility in the mainstream economic literature that hitherto unknown types of agents may enter the models at some future time. We apply the notion of holding times, and introduce the results of the one- and two-parameter inductive methods of Ewens, Pitman and Zabell to economic literature. More specifically, we use the notion of exchangeable random partitions of a finite set to produce a simple rule of sucession, that is, the expressions for the probabilties for entries by new or known types, conditional on the observed data. Then Ewens equilibrium distriution for the sizes of clusters is introduced, and its use to examine market behavior is sketched, especially when a few types of agents are dominant. We suggest that the approaches of this paper and the notion of holding times are relevant to agent-based simulations because holding times can be used to randomly select agents that “act” first. [ABSTRACT FROM AUTHOR]

This paper reports on how the abstraction approach of multi-agent systems can be used to represent the complexity inherent in the urban traffic domain, accounting for the importance of modelling travellers’ behaviour and their interaction with intelligent transportation technologies. A key premise in the approach proposed is the identification of what we have coined autonomous decision entity, which is defined as an agent shell to structure the way agents can be implemented and inserted into the environment. Such a structure is very flexible in the sense it is only defined in meta-level, comprising sensors, effectors and a reasoning kernel. The conceptual multi-agent model is presented and implemented within the DRACULA simulation suite, which is used for simulation experiments on the analysis of drivers’ route and departure time choice. [ABSTRACT FROM AUTHOR]

In this paper we evaluate a number of model equations for the soil-water characteristic curve (SWCC), provided a relationship exists for each relevant soil. The models are with two parameters and relate suction to volumetric water content for values of suction higher then air entry value. Logarithmic tranformations are applied to the variables in order to find linear patern. Most of generally used models are also discussed and compared to the proposed. An example is given how to assess the experimental data to define the variable transformation and how to choose the most proper model. The procedure for estimating the air entry value is also presented. [ABSTRACT FROM AUTHOR]

Experimental investigations are the basis for the understanding of the soil mechanical and hydraulic properties of unsaturated soils. The requirements for the testing and measurement equipment are relatively high. Important for planning the test procedures and the development of new testing devices is having experience with saturated soils and having carried out tests under simplified conditions. In this paper, basic knowledge of soil mechanical properties of saturated fine grained and non cohesive soils are reconsidered to include some basic considerations into unsaturated soil models. The aim is to incorporate the state parameters of sand and the equivalent stress of fine grained soils. For this reason some modified approaches are presented and requirements for further experimental investigations are specified. [ABSTRACT FROM AUTHOR]

Object-oriented (OO) methods become more and more important in order to meet scientific computing challenges, such as the treatment of coupled non-linear multi-field problems with extremely high resolutions. This two-part paper introduces an object-oriented concept for numerical modelling multi-process systems in porous media (Part 1). The C++ implementation of the OO design for process objects (PCS) as a class is described and illustrated with several applications. Due to the importance of the encapsulation of processes as individual PCS objects we denote our concept as an processoriented approach. The presented examples (Part 2) are dealing with thermal (T), hydraulic (H), mechanical (M) and componental processes (C) in bentonite materials, which are used as buDer material for the isolation of hazardous waste in geologic barriers. In particular, we are interested in coupling phenomena such as thermally induced desaturation, non-isothermal consolidation, swelling/shrinking phenomena as well as in a better understanding of the coupled, non-linear THM system. [ABSTRACT FROM AUTHOR]

The continued shortage of organs implies that the organ allocation policy determines who lives and who dies. This creates one of medicine's most vexing dilemmas, and the crux of this dilemma is the tradeoff between clinical efficiency and equity. This chapter describes OR models that have been used to study the problem and the related tradeoffs. A taxonomy of the literature is developed, and a description of the key analytical and computational models is provided. Directions for future research are also presented. [ABSTRACT FROM AUTHOR]

The article offers a guide for teaching about the mining process using chocolate chip cookies and toothpicks. It relates different stories of fatal coal mine accidents across China. The objectives of the teaching method presented here are cited. The materials needed to simulate mining process and the questions that can be used in teaching mining process are listed.

The fatigue is the most common way of structural imperfection and, over the time, it has been a problem to the imposed requests and the type of applied load. In this paper, there is a study of the way the resistance fatigue ASTM A-36 is made among two environments: refrigerated and immerged into water at 5 atm hydrostatic pressure through bending tension fatigue tests. After that, some analyses and comparative results with the tested material were carried out. For this study, a mechanism was developed to test fatigue for bending tension to be used inside and outside hyperbaric chamber for the hydrostatic pressure simulation. This study is worth because any resistance confirmation does not exist in immerged fatigue of virgin materials; in other words, all the tests of fatigue were or have being accomplished in materials done in the air. Curves S-N were determined for each atmosphere. The methodology used for verification of resistance to the fatigue was the regression model from a data originated from accelerated life tests and it was possible to verify the environment influence in the phenomenon of the fatigue. [ABSTRACT FROM AUTHOR]

Although there are many simulations of residual stresses in quenched steel components there is little validation of these predictions particularly when the components are large. This is not surprising bearing in mind that the application of the through thickness measurement techniques (mechanical strain relief techniques) are problematic when the components exhibit high levels of residual stresses or triaxial stress state. This paper examines the application the incremental deep hole drilling technique (IDHD) to measure through thickness residual stresses in the quenched solid and hollow steel cylinders. The measured residual stresses are compared with FE predictions. [ABSTRACT FROM AUTHOR]

The paper presents a virtual reality techniques to create and to simulate a skeletal model of human upper limbs. Motions supported by the current version of the system are: arm flexion/extension, arm adduction / abduction and forearm flexion/extension. It's present the differences between VRML and Matlab. A computer system has been developed where a set of forces done by the muscles are parameterized and the limb motion animation, in real time, is achieved through biomechanics equations. [ABSTRACT FROM AUTHOR]

In this paper, we study the problem of computing tail conditional expectations (TCE) or portfolio gains at specific times (T) in the future. We present efficient algorithms to handle the following two cases: (1) we have only one option (call or put) in our portfolio, denoted as a single-stock-single-option portfolio (SSSO); (2) we have a stock and some of its options in our portfolio, denoted as a single-stock-multiple-option portfolio (SSMO). Compared with previous simulation algorithms, our algorithms compute TCE of a given portfolio more efficiently and still maintain the same degree of accuracy. In the SSSO case, we reduce the computational time complexity from the SSSO-Naïve Algorithm's O(m*n) to SSSO algorithm's O(m+n), where m is the number of possible price outcomes for an underlying stock at time T and n is the number of possible price outcomes for an underlying stock at time U (maturity) in respect to each possible price outcome for an underlying stock at time T. In the SSMO case, we provide two algorithms to compute the TCE. The computational time complexity of the SSMO-Naive Algorithm is O(q*m*n+m*log(m)), where q is the number of options. The computational time complexities of our two algorithms are O(q*(m+n)+m*log(m)), and O(q*log(q)+n+m*q+ m*q*log(q)+m*log(m)) or O(q*log(q)+n+m*q+m*q*log(m)+m* log(m)). In both cases, our experiments show that when m and n are greater than five thousand, our algorithms run thousands of times faster than the naive algorithms. [ABSTRACT FROM AUTHOR]

The continued advancement of software-defined radio (SDR) technology has been a key factor in furthering research about the implementation of most signal processing algorithms at baseband. Traditionally, most algorithms have been carried out at radio frequency (RF). With the coming of SDR, the processing can be done at baseband frequencies which are more compatible with the fast developing software radio technology. This paper looks at matched filter detection and investigates the possibility and benefits of carrying out the detection process at quadrature baseband (QBB). A simple chirp signal is considered for the analysis. The analysis is carried out using MatLab simulations at RF and QBB and the results do show the possibility of carrying out the detection process at QBB with the expected benefits as compared to carrying out the process at RF. [ABSTRACT FROM AUTHOR]

Shape optimization is numerically a very demanding process, where several traditionally separate numerical processes meet together in a heterogeneous multidisciplinary environment. Typical elements involved are (1) the optimizer itself that implements the selected search strategy, (2) the parameterization procedure that provides the bidirectional mapping interface between the 3D geometric shape of the object and a limited number of parameters that control the parametric model of the geometry, (3) the simulation program that provides the results of the simulated interaction between the object and its environment (such as finite element analysis, FEA), and (4) control procedures that monitor the overall workflow and invoke mutual application calls (process flows and data flows) and handle data mining as well as acceptance or rejection of individual instances of candidate designs which are numerically generated and analyzed. In this paper, the set-up of this complex process, combined with evolutionary optimization, is developed with the objectives of numerical flexibility, computational efficiency in terms of combining sequential and parallel execution of individual applications, and low-cost implementation within an unmanaged computer cluster based on the Windows Communication Foundation, WCF. [ABSTRACT FROM AUTHOR]

Recently, the importance and necessity of engineering analysis has shown a steady growth. However, researchers working in small and medium enterprises know little about the usefulness of engineering analysis and suffer from lack of technical knowledge. Axial fan is air fluid machinery in various fields of industry such as automobile, electric appliance, and heavy machinery. It is also a time and budget consuming equipment to develop the axial fan through physical experiments. In order to overcome this problem, we have designed and developed a web-based axial fan simulator using supercomputer. In our simulator, all of processes for engineering analysis including pre-process, solving, and post-process can be performed automatically without user intervention after transferring fan model(CAD files) made by user. After executing the simulator with some parameters, user can receive report including P-Q curves. In this paper, we introduce the architecture of our easy and efficient automated axial fan simulator, related techniques and result of development. [ABSTRACT FROM AUTHOR]

Globalisation and competitive pressure force many SME organizations' to radically change business processes. Although this approach can provide significant benefits such as reducing costs or improving efficiency, there are substantial risks associated with it. Using simulation for modelling and analysis of business processes can reduce that risk and increase the chance for success. This paper exploits the potential of simulation to be used for modelling business processes and supports the case for a wider use of simulation techniques by the business community. Following a discussion on business process modelling methods and tools, the usability of simulation modelling for evaluating alternative business process strategies is explored by way of case study in the bus manufacturing domain. [ABSTRACT FROM AUTHOR]

This paper presents a physical model of a squirrel cage induction machine with rotor topology. The machine is modeled in Modelica, an object oriented multi physical modeling system. The presented machine model is used to investigate electrical rotor asymmetries in induction machines. For the case of a single broken rotor bar a simulation model is compared with measurement results. [ABSTRACT FROM AUTHOR]

A thermodynamic model for the simulation of a spark ignition engine running on alternate hydrocarbon fuel is presented. This paper aims to develop a simple, fast and accurate engine simulation model without the need for a great deal of computational power or knowledge of precise engine geometrical data. The model is based on the classical two-zone approach, wherein parameters like heat transfer from the cylinder, blowby energy loss and heat release rate are also considered. The general fuel is specified by way of its C-H-O-N values. Curve-fit coefficients are then employed to simulate air and fuel data along with frozen composition and practical chemical equilibrium routines. The calculated data is then used to plot the various thermodynamic parameters with respect to crank angle. [ABSTRACT FROM AUTHOR]

Prediction of tool wear in rapid production of sheet metal stamping in automobile industries is a highly challenging task as there are many control parameters involved in the production of automotive panels. This paper presents a numerical simulation methodology to investigate the effects of various processing parameters, such as the lubrication, binder pressure and surface coating, on the critical tool worn area of a certain sheet metal stamping die used in automotive production. The simulation was performed using the finite element software AutoForm™. Various contact pressure distributions and tool wear predictions at the critical tool worn section of the die-workpiece interface, using different processing parameters, were obtained in the simulation, which provide informative guidelines for the on-site production. [ABSTRACT FROM AUTHOR]

unlike the trial-and-error as the destiny of simulation, a backward then forward simulation (BFS) technique with multiple-objectives is developed. We apply BFS to a job shop scheduling problem. The objectives are improving utilization of resources and meet the due date commitment of jobs. The system we studied is under incessant input and decision making. And the goal of this research is to derive a real time reflection, stable and controllable dispatching solution with the authentic meaning in practice for real world. In the viewpoint of scheduling technique, we are using the capability and contribution of BFS to reduce the job shop problem into a station of parallel machines scheduling problem. Then, by integrating the decisions over time we achieve the global objectives control. The objectives are utilization and available to promises instate of makespan and tardiness. The discussion in this research is implemented into a system and practice on some reality sites. The related case study report has been accomplished in an accompany paper [1]. [ABSTRACT FROM AUTHOR]

This paper presents harmonic analysis of motor current signatures under different fault conditions of medium and high power Variable Frequency Drive (VFD) systems. Computer simulation of a VSI fed induction motor based on constant voltage/frequency (V/f) operation is implemented using Powersim (PSIM) simulation software. Frequency response characteristics of motor currents are compared to analyze fault conditions in motor drive system. [ABSTRACT FROM AUTHOR]

In this paper two different techniques of Kalman Filtering and their application in multi sensor data fusion are studied. Two different Kalman filtering techniques such as CKF and DKF are modeled and the effectiveness of their application in multi sensor data fusion is compared with each other. All of the kalman filter models have been simulated in MATLAB and simulation environment. [ABSTRACT FROM AUTHOR]

In this paper, we use two-stage hybrid models consisting of unsupervised clustering techniques and decision trees with boosting on two different data sets and evaluate the models in terms of top decile lift. We examine two different approaches for hybridization of the models for utilizing the results of clustering based on various attributes related to service usage and revenue contribution of customers. The results indicate that the use of clustering led to improved top decile lift for the hybrid models compared to the benchmark case when no clustering is used. [ABSTRACT FROM AUTHOR]

Chapter 6 of the book "Older Persons in Southeast Asia: An Emerging Asset" is presented. It explores the potential efficacy of a universal non-contributory pension (NCP) scheme in Vietnam. It notes the impact on poverty rates among older persons of a universal NCP scheme. It cites the results of financial simulations on the cost of the scheme for all persons aged 60 and above.

In wireless ad hoc network applications, such as outdoor teaching, battlefield, scenes of a fire, flood, and earthquake a number of mobile hosts (MHs) may sometimes move together and sometimes separately. Members within the group have similar mobility patterns and can directly communicate with each other. In this paper, we propose a Group Partitioning and Merging Mobility (GPMM) model for Mobile Ad hoc NETtworks (MANETs). It provides a better reflection of group movement behavior with possible group partitioning and merging. The model presents the trip chain of individuals belonging to a single home. During daily activities, they move from home to some locations and return back after completing daily tasks. Alternatively they partition and merge at some reference points placed on the trip chain. Therefore, at reference points the group members dynamically re-configure themselves triggering group partitioning and merging. We do performance evaluation by simulation. The simulation is written by the network simulator (NS-2) and the graphs are generated using MATLAB. [ABSTRACT FROM AUTHOR]

This paper presents a fuzzy sliding mode controller used for switched reluctance motor speed regulation. Based on the technique of variable structure control (VSC) with sliding mode, we can construct the controller that possesses the merits of both fuzzy controller and variable structure controller. It is called a "fuzzy sliding mode controller" (FSMC). It provides a simple way to solve the main drawback of VSC by reducing the amount of chattering effect using a fuzzy control part in the proposed controller. Also, the VSC part makes the system stable which treats the main disadvantage of fuzzy controller when being used alone. The speed control simulation results are obtained by using the proposed FSMC and the traditional PI controller under different operating conditions. Also, sensitivity analyses simulation results for parameter variations are obtained to check the robustness of the system when using the proposed controller. Finally, the experimental controlled system is illustrated for closed loop and experimental results are presented which show the validity and effectiveness of the proposed FSMC. [ABSTRACT FROM AUTHOR]

The objective of this paper is to propose a novel standardized cam system with motion adjustable. First, generalized Oldham couplings are described. Then, the proposed system is presented. It is composed by a motor, a constant speed coupling, a gear reducer, a variable speed coupling, and a standardized cam mechanism. Then, the feasibility is validated by kinematic simulation using ADAMS software. Finally, the prototype of proposed system is illustrated. The results show that the proposed system can produce required adjustable output motion. In addition, it has the advantage of lower cost, easy accessibility, and high precision. [ABSTRACT FROM AUTHOR]

Robust loop shaping control is a feasible method for designing a robust controller; however, the controller designed by this method is complicated and difficult to implement practically. To overcome this problem, in this paper, a new design technique of a fixed-structure robust loop shaping controller for a highly maneuverable airplane, HIMAT, is proposed. The performance and robust stability conditions of the designed system satisfying H∞ loop shaping control are formulated as the objective function in the optimization problem. Particle Swarm Optimization (PSO) technique is adopted to solve this problem and to achieve the control parameters of the proposed controller. Simulation results demonstrate that the proposed approach is numerically efficient and leads to performance comparable to that of the other method. [ABSTRACT FROM AUTHOR]

Online auctions have expanded rapidly over the decade and had turn to a fascinating new type of business or commercial transaction in the digital era. Bidding in an online auction is a very challenging task as the bidder is not acquainted with the amount, time and also venue. The bidders will end up winning or losing in an auction. One of the ways to ensure a winning bid is for the bidder to try and predict the closing price of a given auction. However, it is not easy to predict the closing price of an auction since it depends on several factors such as the amount of identical auctions running, the amount of participants as well as the behaviour of every individual bidder. On top of this, there can be multiple auctions running concurrently at the same time that can influence the auctions results. This paper discussed on the prediction of online auction closing price using two well known theories which are the Grey Theory (GT) and the Artificial Neural Network (ANN) -- Backpropagation (BP). The prediction, accuracy and effectiveness for both models will be evaluated using a simulated auction environment. [ABSTRACT FROM AUTHOR]

This paper studies the cardiovascular response under heart failure condition supported by two types of ventricular assist devices (VADs): the positive displacement pump and the impeller pump. The cardiovascular system is modeled using the concentrated parameter method developed previously, by considering flow resistance, vessel elasticity and inertial effects of blood in individual conduit segments. The dynamic modeling of displacement and impeller pumps is represented by VAD inlet/outlet flow-rate changes. Results show that in each simulation, the diseased ventricle is effectively unloaded, and the physiological variables of arterial pressure and systemic flow are adequately maintained. The numerical model is under further development for more sophisticated studies of the interaction of the native cardiovascular system with VAD support and other cardiac prosthetic devices. [ABSTRACT FROM AUTHOR]

The emerging dominance of lean and agile techniques is resulting in a worldwide trend towards shorter product cycles, with smaller lead times and shorter production runs. Simulation is a time-consuming processes and data collection is such a major part of the time period of such a cycle. This paper introduces the circuit of observation concepts which provide a massively reduced cycle time for data collection; this makes it a much more valuable tool in a manufacturing environment and expands its uses due to its greater flexibility. The case study strongly supports the findings. [ABSTRACT FROM AUTHOR]

One of major reasons of failure of solder joints is known as the thermal fatigue. Also, The failure of the solder joints under the thermal fatigue loading is influenced by varying boundary conditions such as the material of solder joint, the materials of substrates(related the difference in CTE), the height of solder, the Distance of the solder joint from the Neutral Point (DNP), the temperature variation and the dwell time. In this paper, first, the experimental results obtained from thermal fatigue test are compared to the outcomes from theoretical thermal fatigue life equations. Second, the effects of varying boundary conditions on the failure probability of the solder joint are studied by using the probabilistic methods such as the First Order Reliability Method (FORM) and Monte Carlo Simulation (MCS). [ABSTRACT FROM AUTHOR]

Several statistical tools and most recently Functional Networks (FN) have been used to solve nonlinear regression problems. One of the tasks associated with all of these methodologies consists of discovering the functional form of the contribution of the explanatory variables to the response variable. In this paper, we tackle this problem using functional network models (FNs). Since these models usually involve from a moderate to high number of parameters, a genetic algorithm (GA) for model selection is proposed. After an introduction of FNs and GAs, the performance of the proposed methodology is assessed using a simulation study as well as a real-life data set. [ABSTRACT FROM AUTHOR]

This paper presents the work carried out by CALPE team on the development of a mathematical model used in the study and simulation of the pantograph-catenarydynamic interaction in high speed railways considering two independent spans of catenary where the transition spans are overlapped. According to the developedmathematical model, a non lineal system of differential equations with variableconstraint depending on the pantograph position has been obtained. In order to verify the correctness of the model, a numerical integration algorithm based on an explicit method of the central differentials has been implemented. The procedure that has been designed allows us to study the more appropiate contact wire configuration, in order to make smoth transition of the pantograph between sets of spans. This procedure can be generalized considering the case of several pantographs, obtaining very realistic simulations. [ABSTRACT FROM AUTHOR]

This paper presents an experimental study for evaluting the decision support value if queueing network (QN) based simulation models for information system design performance. For illustration, queueing network simulation models have been extracted corresponding to three annotated design alternatives of a selected case study. The design alternatives are produced using logical requirements of the selected system. The performance of each alternative is then predicted using quantifiable parameters considering the dynamics of the system such as service time, waiting time and number of entities waiting in the system. In particular, results have shown that the first alternative performs better than the other two in terms of the selected parameters. In general, the case study revealed that QN-based simulation models alternatives in terms of selected parameters and under given assumptions. This is also means that the use of simulation may lead ti better designed information systems. [ABSTRACT FROM AUTHOR]

Clock jitter and its effects on signal-to-noise ratio (SNR) were widely investigated in the published literatures. However, most of the issues mainly focused on white-Gaussian-noise-only clock jitter, based on the scenario (assumption) of ideal interference-free clock circuit design which never existed in reality. This paper presents a realistic analog to digital converter (ADC) performance analysis model based on better realistic circuit noise conditions, particularly investigated on the clock jitter error with the combination of Gaussian noise and circuit noise (interference). An analytical expression for the A/D conversion with such combined clock jitter error is developed. The computer simulations are presented, which showed excellent agreement with the developed expression. Also, a real experiment is carried out to bring forth a comprehensive evaluation in A/D system design. [ABSTRACT FROM AUTHOR]

The verification of the system performances becomes of prime importance and notably with the emergence of the soc, in which, the spurious couplings between the functional circuits can be critical. the needs in terms of system simulation tools become thus very important. This paper is divided into two parts, the first part presents a method to implement the volterra and nonlinear impulse response models in matlab/simulink environment. The second part presents a co-simulation interface between Matlab/Simulink and Goldengate (Agilent Technologie) circuit simulator. [ABSTRACT FROM AUTHOR]

The development of the transformer insulation failure undergoes three stages: insulation aging, incipient faults and a short circuit. This paper presents a complete scheme to simulate single-phase transformers with insulation deterioration and arcing phenomena i.e. in the first two stages. The approach incorporates Transmission Line Methods (TLM), Jiles-Atherton Hysteretic Model, Composite Cassie-Mayr Arcing Model and Dielectric Model. A small 25kVA 11kV/220V power transformer with aging and incipient faults is taken as example for simulation. [ABSTRACT FROM AUTHOR]

Staff attrition is a problem often faced by software development organizations. We used process modeling and simulation to estimate the effect of different staffing policies on the project cost. A simulation technique has been used for analyzing the effect of the policies pertaining to replacement for engineers who leave the project, and also overstaffing in the beginning of the project. This paper presents the simulation technique for optimizing the cost of staffing by analyzing replenishment level and replenishment strength with respect to attrition. [ABSTRACT FROM AUTHOR]