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Abstract: A detailed mathematical simulation and experimental investigation of airflow in solar chimneys is studied in this paper. Several experimental studies were carried out on the solar chimney; their choice depends on the parameter of the design and the thermal performances for different geometrical configurations. The experimental tests show that the field speeds in the chimney is influenced by the width of the channel and also of the angle of inclination of the chimney. Therefore, investigations have been carried out in this paper to find the effect of inclination on the performance of solar chimney in Ouargla Province, Algeria. The simulation of this problem is implemented into the commercial CFD code Fluent 6.3. 26. The conservation equations of mass, continuity and energy are solved by the Finite Volume Method. The validation of the results is presented. An good agreement between the experimental results and simulation ones is observed. [Copyright &y& Elsevier]

Abstract: Robot is widely used in industrial domain and pose accuracy of end-effector is an important indicator for judging robot performance. Calibration is a necessary for operating industrial robot and an effective and efficient means of accuracy improvement. This paper describes the development of a calibration procedure for a five degree of freedom serial robot using the laser tracker. The main goal of this paper is to utilize measurements relative to the end-effector of the robot to compensate errors. The robot kinematic model is computed to help identify the deviations. Robot parameter deviations can be identified so that the nominal parameters can be corrected. The experimental results are validated effectively. [Copyright &y& Elsevier]

Abstract: Recently, various control models have been developed to optimize the performance of wave energy converters in order to enhance their long term economic value. Among others, the control of the all-electric Power Take Off (PTO) has been actively studied. This paper introduces the application of bio-inspired Ant Colony Optimization (ACO) metaheuristic as decision support for real-time wave energy extraction. It is found that the performance of the proposed algorithm is appealing as it is able to provide optimal parameter values to the control model within short interval. This provides fast-tuning capability to the PTO while sparing suffcient time for the WEC to respond to the continuously changing sea states. [Copyright &y& Elsevier]

Abstract: The synthetic jets have been identified as a promising technique for various fields of both dynamic fluid and aerodynamics, by using different numerical simulations which recently have been played an important role in their development. In the aim to provide the flow mechanisms by influencing both their visualization and their theoretical analysis provided by the implementation of the different validation code, several passive and active techniques have been studied to explore particularly their characteristics. The present work investigates the performance of the Moving Boundary technique which is one of many different computational tools implemented to reproduce the flow behavior of a 3D synthetic jet. The experimental work is a well stabilized test case used as a CFD benchmark by the CFDVAL 2004 workshop. The main feature of the present work is in use of a moving boundary implemented by use of generating computational mesh at every time step of the unsteady computation. Results are first intended to calibrate versus the measurement in order to be sure that phases are accordance. Several points and lines positions are chosen to compare the averaged velocity components. The preliminary results are encouraging and allow reproducing at least qualitatively the flow behavior animations of the synthetic jet. Nevertheless further improvements have to be added, mainly in grid generation and probably in turbulence model selection. The results given in this paper will be used for validating perspective computational studies to control the boundary layer separation. [Copyright &y& Elsevier]

Abstract: According to a majority of static evaluation and without common significance problems of regional environmental performance evaluation, evaluation indicator system of regional environmental performance is established in view of evaluation indicator system design principle, which is composed of environmental investment, operational performance, environmental condition and environmental profit. A dynamical model on regional environmental performance evaluation is put forward in this paper, which is combined with the basic idea of DEA and fuzzy integral assessment method. In order to provide the reasonable basis for local government to take corresponding measures to improve their environmental performance level, we carry through empirical analysis about regional environmental performance of 8 typical western regions in china and draw conclusion. [Copyright &y& Elsevier]

Abstract: In order to control the position of hybrid stepper motor and improve its performance, direct torque control strategy is adopted. The main idea of this paper is to present the implementation of an emotional controller for position control of hybrid stepper motor drive. The proposed controller is called Brain Emotional Learning Based Intelligent Controller (BELBIC). This controller is a computational model of emotional processing mechanism in the brain. The effectiveness of the proposed BELBIC controller-based hybrid stepper motor drive is verified by simulation results. [Copyright &y& Elsevier]

Abstract: In classical methods only average torque of the stepper motors is controlled which causes high speed and torque ripple. In order to control the torque instantaneously and improve the performance of the hybrid stepper motor, direct torque control strategy is used in this paper. Then by taking model reference adaptive system scheme, which uses the hybrid stepper motor itself as the reference model, speed of the motor is estimated. The sensorless control of hybrid stepper motor based on MRAS is built and simulated with Matlab software. The results show that this control technology is simple and effective and accuracy of the estimation is considerably high. [Copyright &y& Elsevier]

Abstract: In this paper, a practical method to design a robust controller for pressure of boiler in Mashhad Power plant using H∞ is proposed. To achieve a good performance of an industrial boiler in order to reduce fuel consumption rate and reaching higher efficiency, dynamic variables such as fuel flow, air flow and pressure of boiler must be controlled. However this dynamic model may associate with uncertainties. Uncertainties in mentioned model are caused by lack of knowledge about the dynamics of the system, pay load changes, and air flow. Thus, application of robust control methods for high precise control of pressure is inevitable. In the first step plant is identified by using experimental data by the mean of converting into a group of linear time invariant (LTI) uncertain plants. After representation of the uncertain dynamic system in general control configuration and modelling the parametric uncertainties, nominal performance, robust stability and robust performance against disturbances are analyzed by the concept of structured singular value μ. Then, using genetic algorithm an optimal controller is designed for tracking problem and disturbance rejection. This procedure gives a satisfactory controller at the presence of model perturbations. For more comparisons, quantitative feedback theory (QFT) as a well known robust control approach is also applied to the plant. Finally, nonlinear simulation has been carried out and two controllers are compared. Both optimal robust controllers guarantee robust performance of the system against the uncertainties and result in desired time responses of the output variables. By applying H∞ robust control, system tracks the desire reference inputs in a less time and with smoother time responses. [Copyright &y& Elsevier]

Abstract: It is difficult to evaluate the performance of the different companies feasibly and fairly only depending on experts. An evaluation model based on TOPSIS (Technique for Order Preference by Similarity to Ideal Solution) is built to solve this problem. In this model, the method of data processing and the evaluation algorithms are analyzed detailed. By means of the evaluation model, eight electric power supply bureau of Chongqing are evaluated in this paper, and the results show feasibly and reasonably. [Copyright &y& Elsevier]

Abstract: In this paper, we propose an autonomous Smart Grid operation by using multi-agent approach. The proposed multiagent system consists of five types of agent: single Smart Grid controller agent (SGC), several Load agents (LAGs), several green power generation agents (GPAGs), several gas-turbines agents (GTAGs), and several battery agents (BAGs). In a Smart Grid, LAGs act as consumers or buyers, GPAGs and GTAGs act as producers or sellers, and BAGs act as prosumers or sellers/buyers. In order to verify the performance of the proposed method, it applied to a simple model system with different electrical power rates (peak rate and off-peak rate). From the simulation results, it can be seen the proposed multiagent system could perform the Smart Grid operation efficiently. [Copyright &y& Elsevier]

Abstract: Power Conditioning System (PCS) in the photovoltaic system requires reliable islanding detection function (passive or active) in order to know electrical grid status and operate the grid connected inverter properly. This paper proposes a passive islanding detection algorithm based on the grid harmonic components. It utilizes the fact that the equivalent harmonic components at the point of common coupling (PCC) are changed according to the grid connection status. This method shows reduced Non-Detection Zone (NDZ) and fast detection time compared to the conventional approach. The mathematical modeling is performed and verified by experimental result using high performance DSP controller [Copyright &y& Elsevier]

Abstract: Messaging system can be treated as a collection of message channels, ending points, messaging routers, and process management. For a particular application, the implementation style of the underlying messaging system is not unique. However, different approach results in various performance and resource requirements. In this paper, a testing environment is designed to investigate the performance and resource requirements features of various implementation techniques of a message system. The alternative implementation of the message channel, endpoint, routing and process management is organized with the concepts of logical topologies, which present the integration style of a messaging system. The testing experiments are carried along three different topologies: the business process management pipeline, the enterprise service bus, and enterprise service network. The pseudo web service clients and web service providers is implemented to simulate the workload effects of a real environment. From the detailed analysis of the testing results, it is validated that the ESB model provides the most flexible message delivering service with the cost of largest transaction throughput, but consumes the smallest of processor usage and memory occupation. [Copyright &y& Elsevier]

Abstract: Dynamic trustiness evaluation of software has become a hot issue in information security field. In order to improve the accuracy of evaluation, a Trustiness Evaluation Model Based on Software Behavior (TEMSB) is proposed in this paper. TEMSB introduces Software Behavior Trace (SBT) to describe software behavior. SBT consists of operation trace, which is composed by operation sequences of the running software, and function trace depicted by a series of scenes. With the purpose of reducing time and space overheads of trustiness evaluation, we present reduction rules for SBT. In our model, we apply identification evaluation rule and scene evaluation rules to check the practical behavior of software. In particular, we consider a kind of special check points, named as branch points, at which we determine branch directions through scene information. The simulation results indicate the precision and efficiency of TEMSB. [Copyright &y& Elsevier]

Abstract: This paper introduces a solution, Device Management Load Balancing Solution (DMLBS) which includes system design and load balancing algorithm, to achieve load balancing on Device Management server. Our solution improves both user response time and throughput for a single Device Management server, while exposing one interface to clients. DMLBS achieves its performance by using dynamic adaptive load balancing strategy and designing a mathematic model to measure Device Management server load. With these means, compared to two well-known load balancing algorithms (LeastLoaded and Round-Robin), DMLBS provides outstanding performance on load balancing. [Copyright &y& Elsevier]

Abstract: This paper discusses a batch arrival queue with delayed single working vacation. Whenever the system becomes empty at a normal service completion instant, the server will enters into the delay period and will return into a normal busy period immediately without vacation period if an arrival occurs during such a period. Otherwise he will go for a single working vacation. We derive the queue size distribution at random epochs and departure epochs. We also derive some important performance measures of this model. Finally, several numerical examples are presented. [Copyright &y& Elsevier]

Abstract: Conventional multimodal biometrics systems usually do not account for missing data (missing modalities or incomplete score lists) that is commonly encountered in real applications. The presence of missing data in multimodal biometric systems can be inconvenient to the client, as the system will reject the submitted biometric data and request for another trial. In such cases, robust multimodal biometric verification is needed. In this paper, we present the criteria, fusion method and performance metrics of a robust multimodal biometrics verification system that verifies the client''s identity at any condition of data missing. A novel adaptive SVM classification method is proposed for missing dimensional values, which can handle the missing data in multimodal biometrics. We show that robust multibiometrics imposes additional requirements on multimodal fusion when compared to conventional multibiometrics. We also argue that the usual performance metrics of false accept and false reject rates are insufficient yardsticks for robust verification and propose new metrics against which we benchmark our system. [Copyright &y& Elsevier]

Abstract: This paper aimed to study the effect of paddle number and immersed radius ratio on water wheel performance. The water wheel models were tested for their performances in water channel. 3 HP pump was used to circulate the water with the velocity in the channel of 0.3 m/s. The torque load was varied and the rotational speed was measured then the maximum power was determined for each water wheel model. The paddle number was varied from 6 to 12. The immersed radius was varied from 0.05 to 0.15 m when the whole radius of water wheel was fixed at 0.20 m in order to obtain the immersed radius ratio of 0.25, 0.5 and 0.75. From the result, it was found that the highest performance occurred when the paddle number was 6 and the immersed radius ratio was 0.5. The torque load at the maximum power depended on the immersed radius ratio. And at the same immersed radius ratio, the 6, 8 and 12 paddle number water wheel models had the same torque load at the maximum power. [Copyright &y& Elsevier]

Abstract: This paper focuses on the performance and dynamic behavior of proton exchange membrane fuel cell (PEMFC) with 1.2kW under varies of an input load current. The mathematical model of PEMFC is developed based on energy, mass, and electrochemical equation. The some parameters in the model are kept constant. The performance and dynamic behaviors of PEMFC are determined by applied the variety of input load current with different types of input load current, such as saw-tooth, step, step input with dead time, and multi-step input load current. The results of model are compared to the experimental results. The results of the model show that the output cell voltages are suddenly dropped when the input load current have been increased and output cell voltage increased when decreased the input load current. This mathematical model can predict the dynamic behavior of the PEMFC when the input load currents have been changed. The experimental setups use 1.2kW of PEMFC with connected to electronic load device and can be operated the input load current from 0A to 500A. Hydrogen is used as a fuel at the anode side and air is used at the cathode side. The operating temperature is kept to be constant at room temperature. The experiments show that the output cell voltage is decreased when the input load current increased. There is some slightly different between the model and experiment results when compared at the same conditions. This is because of in the model we kept some parameter constant. The water generated during the process is tested under varying input load current from 1A to 30A. The dynamic behavior of the PEMFC under different types of input load current shows very well. [Copyright &y& Elsevier]