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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: This paper analysis the cushion performance of the bucket unit for molded pulp material model, which based on the ANSYS software to simulate the compression test and study the effect variety of the draft angle and the height on the model. [Copyright &y& Elsevier]

Abstract: This paper presents a method of calculating an advance angle in order to increase the torque-to-current ratio of a brushless DC (BLDC) motor. The BLDC motor is widely used in various industrial fields because of its high energy density and low maintenance. Because the BLDC motor drives with a square-wave current of electrical 120 degrees duration, the phase current must be commuted every 60 electrical degrees of rotation. Owing to the inductance levels of the motor winding process, the commutation induces a phase lag and deviations from the ideal square-wave current form. These non-ideal characteristics reduce the torque-to-current ratio. Advancing the commutation timing can improve the torque-to-current ratio. This paper analyzes the torque performances of the BLDC motor and proposes a method of calculating the advance angle in order to improve the torque-to-current ratio. The simulation results of a 20W, 20,000rpm BLDC motor verify the effectiveness of the proposed calculation method. [Copyright &y& Elsevier]

Abstract: The higher power microwave heating source, in the industrial and engineering needs, is obtained through inputting microwave energy of multi-open feed into cavity via near-field radiation, resulting in the coupling of each feed. Meanwhile, the initial situation, the ratio of fluid and the permittivity are highly nonlinear in the process of microwave heating during technical operation process by microwave heating process cycling fluid medium. This paper is presented an improved Anti-predatory Particle Swarm Optimization (APSO) algorithm to optimize the three parameters of PID controller, and is applied to control the complicated and coupling of microwave heating. It is shown through intelligent calculation and simulation experiments that the improved APSO has good performance. And this paper provides an alternative for control of multi-couple and uncertain objects in industry. [Copyright &y& Elsevier]

Abstract: A fast development of high speed railways is witnessed in recent years as well as the performance of its wireless communication systems, GSM-R. In GSM-R systems, a large percentage of call outage is induced by handoff process. Thus, handover is a critical issue of reliability performance in GSM-R systems. Most of existing investigation and practical designs for handover in GSM-R systems are mainly based on single antenna without considering the specificity of the train as hard handover. In this paper, we take full use of the length of the train and propose a novel scheme of seamless fast handover based on Dual-Antenna. In this scheme, two antennas are respectively installed at the head and the end of the train and the proper coordination of the two antennas turn it to a soft handover. In the interlacing area of two antenna cells, the head antenna handover in advance while the end antenna connects to the current cell until the front antenna connect the new cell reliably. In this way, we can achieve a seamless and fast soft handover. This paper introduces the details of the scheme and analyzes the feasibility. Simulation results show that the proposed scheme is more efficient than existing schemes in terms of handover delay and reliability. [Copyright &y& Elsevier]

Abstract: Our commitment is the development of an industrial-grade Class AAA solar simulator based on LED technology . Presently, the LEDSim™ covers the full wavelength range of interest for Si-PV with an extension in the UV, matching AM1.5g from 350nm to 1100nm. To achieve user-defined target spectra we apply 22 different LED packages including several uncommon types. We present a measured spectrum tuned to AM1.5g. It follows from rare lifetime information for some LED species that we need to set a strong focus on reliability determination for our lightheads. In this paper we show how we confirm the lifetime promise of the LED technology with reliability testing. Modern design-for-reliability methods are taken into account in order to increase the reliability of the LEDSim™. Beam shaping and homogeneity are key functions of a sun simulator, and a large effort is made on achieving Class A homogeneity for each wavelength interval as specified in IEC 60904-9 . We are testing different kinds of LED optics and add mirror channels to achieve the best relation between homogeneity and intensity. [Copyright &y& Elsevier]

Abstract: The hybrid controls are the controls combining several techniques. Their purpose is to benefit from performance of each of these techniques. The control proposed in this paper is based on this hybrid approach; combining the performances of the controls which are based on the tools of the artificial intelligence (artificial neural networks and fuzzy logic) applied to control the single-phase induction machine without capacitor supplied by voltage source inverter. The application of this approach to the single-phase induction machine is a contribution to the study of this machine. Indeed, this type of machine has not yet taken its whole share from various works present until now, compared to the three-phase induction machine. The simulation results show the feasibility and good performance obtained by the proposed control. [Copyright &y& Elsevier]

Abstract: This paper presents a practical multicast routing, which dynamically transforms a conventional multicast tree into a multicast mesh and increases the opportunities for coding by applying double direction network coding scheme. The simulation shows the proposed algorithm is a practical multicast routing, and it has better performances by comparing with ODMRP and MORE-M in terms of coding gain and packet delivery ratio. [Copyright &y& Elsevier]

Abstract: There are many methods available for Load frequency control in an interconnected power system. This paper deals with tuning of PID controller for Load frequency control. A two area thermal power system is considered for study. Both the areas are equipped with PID controller. Parameters of these PID controllers are obtained using Particle Swarm Optimization. A comparative study on tuned values has been presented to verify effectiveness. Ziegler-Nichols method is used for tuning of parameters for comparative study. The simulation results demonstrate the effectiveness of the designed system in terms of reduced settling time and oscillations. MATLAB/SIMULINK was used as simulation tool. [Copyright &y& Elsevier]

Abstract: The hybrid power sources, particularly type renewable is one of advanced solutions in the field of energy including wind-photovoltaic type, designed to ensure reliability of system operation or chain energy conversion with better management and control. In this paper, we analyze the modeling and simulation of an energy conversion system based on a double-fed induction machine (DFIM) powered by a hybrid renewable source. The results obtained are very advanced and satisfactory. [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, performance of the liquid desiccant dehumidification system in evaporation coolers was investigated by the Second Law of Thermodynamics analysis. This system was designed and manufactured for this purpose. Lithium chloride (LiCl), as liquid desiccant, and a packed bed column were used for dehumidification. The described system includes a part for processed air simulation in various temperatures and humidities. Entropy generation of the liquid desiccant dehumidifier was analyzed based on the second thermodynamic law. The effect of inlet parameters of the dehumidification column on the entropy generation was also investigated. The results showed that the entropy generation was highly dependent to operational conditions and inlet parameters of the desiccant dehumidification column. [Copyright &y& Elsevier]

Abstract: Reactive power optimization plays a significant role in the operation of wind farm grid intern connection to maintaining voltage stability and system reliability. Genetic algorithm (GA) is an efficient method which can be applied in reactive power optimization to reduce power loss and improve power quality. However, traditional GA has some defects, such as slow convergence and prematurity. For improvement, the paper modified decoding method, genetic operators, crossover and mutation probability, iteration stopping criterion based on the theory of Catastrophism. A reactive power optimization techniques based on improved genetic algorithm (IGA) of wind farm is such presented. Simulation results for Chinese Mongolia Huitengliang Power Plant show that the proposed method has satisfied global performance, high convergence speed and stable convergence performance, so it is suitable to solve the optimal reactive power planning. [Copyright &y& Elsevier]

Abstract: The microturbine based Distributed Generation (DG) system are becoming the popular source of power industries due to their fuel flexibility, reliability and power quality. The microturbine generation (MTG) system is a complicated thermodynamic electromechanical system with a high speed of rotation, frequency conversion and its control strategy. In spite of several techniques to control high speed of microturbine is not accurate and reliable due to their anti-interference problem. To resolve the anti-interfacing problem, this paper investigates the fuzzy logic based speed governor for a MTG system as an alternative to nominal PI or lead-lag based controller. The development of fuzzy logic based speed governor includes input and output membership function with their respective members. The load variation on MTG system is performed using conventional and fuzzy logic controller, implemented in Matlab/simulink and results are compared with each other. The simulation result shows that, the performance improvement of fuzzy logic governor over a nominal governor based MTG system. [Copyright &y& Elsevier]

Abstract: In this paper, the yearly performance of a library building located in Harbin, China, equipped with a ground-coupled heat pump (GCHP) system, was simulated and its ground heat exchanger (GHE) was designed in the TRNSYS 17 environment. Utilizing the hourly load simulation results, a TRNSYS model was developed to analyze underground thermal balance of the entire system, obtaining the 30-year operation conditions of the reference building. According to simulation results, annual average storage temperature, the highest and lowest inlet temperature of the heat pump, factors that influence efficiency of the system, change as the number of boreholes changes. And the optimized length of heat exchangers was studied, as well as method of determining the concentration of antifreeze in heat-transfer fluid in cold regions. [Copyright &y& Elsevier]

Abstract: Nowadays, distributed generations (DGs) have taken a special role in power systems. Distributed generations have received significant attention as a means to improve the performance of the electrical power system, provide low cost energy, and increase overall energy efficiency. A problem with such generators is the unwanted islanding phenomenon. Islanding detection an important and challenging issue to power engineers. Several methods based on passive and active detection scheme have been proposed in the literature. While passive schemes have a large non detection zone (_DZ), concern has been raised on active method due to its degrading power quality effect. In this paper, a new technique to detect islanding conditions has been proposed for micro turbine (MT) as distributed generation. The performance of the proposed method based on passive methods is much more appropriate than that of previous methods. The simulation results performed in Simulink-MATLAB, clearly show improved operation of this method. [Copyright &y& Elsevier]

Abstract: Cooperation diversity allows mobiles share their antennas to achieve uplink transmit diversity. A particularly powerful variation of user cooperation framework is coded cooperation, which partitions the code words of each mobile and transmits portions of each code word through independent fading channels. This paper mainly focuses on coded cooperation, and its improved framework, which is called space-time cooperation, and investigates the application of turbo codes in both frameworks. The analysis and simulation results show that both of the frameworks achieve impressive gains, and space-time cooperation improves the performance of coded cooperation in fast fading. [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: This paper gives the principle of generation of DTMF signal based on the standard of ITU Q.23. Using the GUI interface method of matlab, we implement the simulation of signal generation. Then with the help of FFT algorithm and Geortzel algorithm, we complete the reception of DTMF signal and achieve the feature of frequency domain about the signal. By comparing these two methods, we get the conclusion that Geortzel shows a better performance than FFT algorithm in terms of reception of DTMF. [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 introduced several audio recognizable ways to get different peoples’ voices preferences both in the field of biology and pattern recognition, and a new way to resolve and determine the merits of this model, which we did some experiments to compare different performances on this model and we discuss its assessment for the expected results and potential applications. [Copyright &y& Elsevier]

Abstract: To solve the increasing problem of Inter-cell interference in LTE, put forward an algorithm based on technologies of SRS sounding and Adaptive Modulation and Coding which is proved, in this paper, to be adequately achieve the goal of Inter-cell interference coordination/avoidance. Simulation and analyzing of the algorithm have indicated that it could effectively improve the performance of the subscribers located at the edge of the cells in a certain degree. [Copyright &y& Elsevier]

Abstract: In this paper a cache scheme named Conflict Prediction Cache(CP cache) is presented. Its architecture contains a direct-mapped cache and a small fully-associative cache, and a conflict prediction table(CPT) which dynamically decides the allocation of fetched blocks from next memory hierarchy. SPEC95 Simulation results show that the performance of CP cache is always better than the traditional direct-mapped cache with twice the size of CP cache. For example, with the same block size of 32 bytes, the average improvement of miss rate of (8+1)KB CP cache with 8-entry CPT is about 19% over the traditional 16KB direct-mapped cache. By comparison with other similar architectures such as NTS cache and PCS cache, CP cache not only requires less hardware tradeoff and simpler control but also improves hit rate and bus traffic. [Copyright &y& Elsevier]

Abstract: A background modeling scheme in compressed sensing (CS) imaging system is proposed in this paper, in which background evaluation is performed on the measurement vectors directly before reconstruction. The estimated background measurement vector is constructed through average, running average, median and block-based selective method respectively. Then the estimated background image is reconstructed using the background model measurements through the gradient projection for sparse reconstruction (GPSR) algorithm. The simulations show that the proposed background modeling algorithms in CS scheme provide promising results. [Copyright &y& Elsevier]

Abstract: We have used the metaphor of ant colonies to define “the Ant system”, a class of distributed algorithms for combinatorial optimization. In this paper we analyze some properties of Ant-cycle, the up to now best performing of the ant algorithms we have tested. We report many results regarding its performance when varying the values of control parameters and we compare it with some FEM algorithms. And in accordance with treatment principles, the microstructure of the alloy is simulated. [Copyright &y& Elsevier]

Abstract: Particle swarm optimization (PSO) is an intelligent optimization technique, which has shown a good performance in many real world and benchmark problems. In this paper, we propose an improved PSO variant, called PSO with modified velocity strategy (MVPSO), in which each particle is attracted by the global best particle and a random particle chosen from a set of good particles. In order to verify the performance of MVPSO, ten well-known benchmark problems are used in the experimentas. Simulation results show that MVPSO obtains better performance than standard PSO and two other improved PSO variants. [Copyright &y& Elsevier]

Abstract: Orthogonal frequency division multiplexing (OFDM) suffers from a high peak-to-average power ratio (PAPR).Tone reservation is a popular PAPR reduction technique that uses a set of reserved tones to design a peak-canceling signal. In this paper, the performance and complexity of clipping noise guided, complex base-band active-set methods based on tone reservation for PAPR reduction are analyzed and simulated. The simulation results show that the two clipping noise guided methods, the adaptive scale method and constant scale method, have better performance than complex base-band active-set methods. Furthermore, the complexity of the constant scale algorithm is lower than the adaptive scale and the complex base-band active-set algorithm. [Copyright &y& Elsevier]

Abstract: Computational models of driving behavior developed based on a cognitive architecture can provide better scientific understanding of driving, simulate driving behavior, quantitatively predict possible interference of in-vehicle tasks, and thus help develop human factors guidelines and tools for in-vehicle systems design. Driver lane changing is a common activity in driving. Therefore, modeling driver lane changing with a cognitive architecture should be an important component of cognitive models of driving behavior. In this paper, we develop a computational model of driver lane changing control with the Queuing Network-Model Human Processor (QN-MHP) cognitive architecture based on neuroscience and psychological findings. The simulation and experimental results from lane changing on straight and curved roads suggest that this model can perform the control process of lane changing well and the model''s control process is consistent with that of drivers. [Copyright &y& Elsevier]

Abstract: High fidelity Full Scope Operator Training Simulators play a key role in imparting plant related knowledge to the operating personnel in an effective way. It provides a platform for training the operators on normal and emergency conditions including all types of scenarios that would arise in any Nuclear Power Plant. The scenario based training helps the plant operator to handle a crisis in an efficient manner with the ultimate goal of safe and efficient operation of the plant. This paper discusses about the general description of PFBR Operator Training Simulator, modeling and simulation of various process models, the complexities involved etc. It also covers the associated process logics, controls, display of alarms and indications, malfunctions and transient incidents related to each process model, integration with other sub systems, individual process model testing, integrated performance testing and verification and validation of models. Simulation of process models are broadly classified into two main categories namely, External Models - that are developed in-house and ported to the simulator environment and Internal Models - that are developed using Simulation Tool. External Models are tested on the desk top for intended functioning and after obtaining satisfactory results, the models are ported to the simulator base wherein the Logical and Virtual Panel Models are built to represent a real system of the plant. Internal Models are built using the Simulation Tools and integrated with the External Models after testing. Combination of External and Internal Model represents the total plant and the performance testing is conducted in an Integrated Mode to qua lify the Process Models for training purpose. [Copyright &y& Elsevier]

Abstract: Containment is a key factor of geological CO2 storage: small, localized leaks could have consequences to health and safety (e.g. CO2 accumulation in cellars) and the environment (e.g. drinking water pollution). On the other hand, large leaks could affect wide areas and large populations, and could reduce the overall economic and environmental benefit of the CO2 storage site and of Carbon Capture and Storage (CCS) in general. Containment potential over hundreds of years is affected by unknowns and uncertainties, and it is therefore appropriately dealt with in the framework of risk analysis. One way of estimating containment risk is to use quantitative simulators: if properly calibrated they can predict leakages through potential pathways and, if used properly in a probabilistic framework (e.g. through a Monte Carlo approach), can take into account uncertainties and produce probability distributions of CO2 leaks. This paper will discuss how different methodologies for estimating risk from probability distributions of releases of substances can be reconciled in a consistent, unified approach that can be rigorous or simplified according to the state of knowledge and the degree of detail required in the calculation. [Copyright &y& Elsevier]