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In this paper, neuronal direct power control (DPC) strategy is applied for a doubly fed induction generator (DFIG) based wind energy generation system. Used in three level neutral point clamped (NPC) rectifiers, to directly control the active and reactive power, switching vectors for rotor side converter were selected from the optimal switching table using the estimated stator flux position and the errors of the active and reactive power, also the grid side is controlled by direct power control based a grid voltage position to ensure a constant DC- link voltage. This approach is validated by using MATLAB/SIMULINK software and simulation results can prove the excellent performance of this control as improving power quality and stability of wind turbine. [ABSTRACT FROM AUTHOR]

To meet increased demand in energy while reducing greenhouse gas emissions, different renewable energy technologies are used. The wind power provides potential benefits as it is a clean, renewable, economic and domestically available power source. Building of sustainable wind farm is subject on many different factors. The aim of the paper is to contribute optimal turbines placement and integration to the electrical grid. For this goal, a mixedinteger non-linear optimization model for determination of maximum wind farm capacity is defined. Another linear optimization model is used to determine the minimum distance of wind turbines in the farm to the point of common coupling. The proposed approach is tested numerically for particular wind turbines type and given wind farm area. The testing results demonstrate the applicability of the proposed optimization models for determination of maximum wind farm capacity and minimum distance between wind farm and point of common coupling. [ABSTRACT FROM AUTHOR]

In this paper, a comprehensive algorithm using modified invasive weed optimization is introduced for allocating distribution generation (DG) sources along with considering demand response (DR). Three aspects such as technical, economic and environmental are taken to account to define the optimized size and location for DG or DR. In addition, a new voltage fitness function is proposed for better improvisation of voltage profile. The study is done on 30-bus IEEE transmission system and to examine the proposed algorithm, three other optimization algorithms such as GA, PSO and DE are used. The simulation is carried out in MATLAB which shows excellent performance of the proposed algorithm. [ABSTRACT FROM AUTHOR]

The development and installation of Distributed Generators (DGs) in distribution power networks turned these networks from a passive into active ones in power systems. Proper management and control of these resources can help to improve power quality, and increase security and effectiveness of power networks. The power management of DGs considering their operating cost along with reconfiguration of distribution network can reduce the cost of operation, including cost of energy losses, cost of power purchasing from the upstream network and cost of power generation by dispatchable DGs. In this study a new method is presented for daily reconfiguration of distribution network in presence of dispatchable DGs and renewable DGs in order to reduce the total operating cost of distribution companies. Dynamic modeling of renewable DGs based on uncertainty of their output, switching costs and varying load are considered in this paper. Finally, the method has been tested in three stages on 16-Bus IEEE to demonstrate the effectiveness of proposed method. [ABSTRACT FROM AUTHOR]

The switched reluctance motor is a singly excited, doubly salient machine which can be used in the generation mode by selecting the proper firing angles of the phases. Due to its robustness, it has the potential and the ability to become one of the generators to be used in the harsh environment. This paper briefly discusses the energy conversion by a switched reluctance generator (SRG) when two switches per phase converter circuit and discrete position sensors are employed. It is well known fact that, as the generator's speed increases by a prime mover and the shape of the current waveform changes in such a way that limits the production of generating voltage. At high speeds, it is possible for the phase current never reaches the desired value to produce enough back-EMF for sufficient voltage generation, therefore, the output power falls off. In order to remedy this problem, the phase turn on angle is advanced in a way that the phase commutation begins sooner. Since one of the advantages of this type of generator is its variable speed then, the amount of advancing for the turn on angle should be accomplished automatically to obtain the desired output voltage according to the speed of the generator, meaning, as the generator speed increases so should the turn on angle and vice versa. In this respect, this paper introduces an electronic circuit in conjunction with time reshaping of the command pulses obtained from position sensors and the drive converter to achieve this task for a desired output voltage when a SRG feeding a resistive load. To evaluate the generator performance, two types of analysis, namely numerical technique and experimental studies have been utilized on a 6 by 4, 30 V, SRG. In the numerical analysis, due to the highly non-linear nature of the motor, a three dimensional finite element analysis is employed to calculate some of motor parameters and then using these parameter, current shape and magnitude are computed, whereas in the experimental study, a proto-type generator and its circuitries have been built and tested using two-switch per phase converter. A linear analysis of the current waveform for the generator under different advancements of the turn on angle has been performed numerically and experimentally and the results are presented. [ABSTRACT FROM AUTHOR]

In this paper optimum size and location of the capacitors and distributed generators (DGs) are determined for reliability improvement and power loss reduction using genetic algorithm (GA). The main innovation of this paper is using both DG and Capacitor for the reliability improvement and power loss reduction. For this purpose an objective function consisting of reliability cost, power loss cost and also DG's and capacitor's investment cost are considered. The effectiveness of the proposed method is examined in the 10 and 33 bus test systems and comparative studies are conducted before and after DG and Capacitor installation in the test systems. The results obtained show the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Application of renewable energy sources has shown a perfect potential as a form of contribution to conventional power generation systems. This paper presents a hybrid system based on photovoltaic (PV) module and PEM (proton exchange membrane) fuel cell (FC) with the aim of selling electricity to distribution network (DN) and improving its reliability. In this paper, moreover supplying the load electricity of system, the proposed hybrid system is capable to sale electricity to DN and by electricity injection causes DN reliability improvement. The revenue from selling electricity to DN is considered as the system profit (SP). An optimization is applied to maximize the SP using GAMS environment. This study claims that moreover load electricity provision, electricity can also be sold to DN by proposed hybrid system and reliability of DN in load supplement can be increased by injecting the electricity to it. [ABSTRACT FROM AUTHOR]

This paper presents determination of optimum size and location of distributed generators (DGs) for reliability improvement of distribution systems in the presence of time varying loads using Genetic Algorithm (GA). The main innovation of this paper is considering of the annual load duration curve for determination of size and location of DGs for reliability improvement. For this purpose, a load duration curve, including four load levels with different weighting factor is considered. For reliability assessment, the customer-oriented reliability indices such as SAIFI, SAIDI, CAIDI, ASUI and also load- and energy-oriented indices such as ENS are evaluated. In this paper, the effects of system reconfiguration and load shedding are also considered for reliability improvement. The best size and location of DGs in distribution systems are determined based on different reliability indices, separately. The effectiveness of the proposed algorithm is examined on a standard distribution system consisting of 33 nodes, and comparative studies are conducted in the different cases to investigate the impacts of optimal DGs placement and its size determination on reliability improvement. The obtained results show the effectiveness of the proposed method for reliability improvement. [ABSTRACT FROM AUTHOR]

Image segmentation has been widely used in different applications of the image processing. The main objective of image segmentation is to subdivide the input images to their main components. Generally, the main purpose of the segmentation is to simplify or change an image representation into something that is more meaningful and easier to analyze. In this paper, World Cup Optimization Algorithm (WCO) is proposed to classify the main components of an image (pixels) into different groups. In the experiment, the proposed method performance is measured by comparing with Otsu as a classic method and GA based and APSO based image segmentation algorithms as the heuristic based algorithms for segmentation. When compared with the other segmentation methods, the proposed WCO based method achieved good performance. The final efficiency of the proposed system is compared with the described methods. Experimental results show that the proposed method has overcome the others in the performance. [ABSTRACT FROM AUTHOR]

An ultra-wideband (UWB) common gate-common source (CG-CS) low-noise amplifier (LNA) in a 0.18μm CMOS technology is presented in this paper. A capacitive cross-coupling fully differential amplifier with the current-reuse technique is described that in the entire 3.1-10.6 GHz UWB band, achieves a high and flat power gain with low noise and good input impedance matching among low power consumption. The current-reuse technique is used to achieve a wideband and reduce the power consumption. The capacitor cross coupling technique is used to gm-boosting and hence to improve the NF of the amplifier. Therefore, the dependency between noise figure (NF) and input impedance matching is reduced. The proposed CG-CS amplifier has a fairly low NF compared with the other previous works in similar technology. In addition, a good power gain over all bandwidth and a high isolation with good input/output impedance matching are achieved. The minimum NF is 1.8 dB, the maximum power gain is 14.2 dB, the inverse gain is <-50 dB, and in the entire 3.1-10.6 GHz UWB band, the input and output matching S11 and S22 are < -10.3 dB and <-11.3 dB, respectively. The input third-order intercept point (IIP3) is -5 dBm. Moreover, the power consumption of the core is 10.1 mW with the supply voltage of 1.8 V. [ABSTRACT FROM AUTHOR]

Quantum-dot Cellular Automata (QCA) is a computational technology that can be used to construct nanoscale circuits. Nowadays, this technology is a good alternative for CMOS technology due to features such as high speed, low occupied area and low power consumption. Memory is utilized as one of the basic elements in digital circuit design hence the design and optimization of high-speed RAM memory cells have become one of the most attractive research areas; in the realm of QCA. In this paper, we present a comprehensive investigation on RAM memories. For this purpose, the proposed schemes in terms of functionality, the number of cell consumption, and latency are implemented and compared using QCA Designer software. The results show that some of the proposed schemes show better performance in terms of parameters such as occupied area and delay. Nevertheless, they are still suffering from less stability; hence introducing an optimum scheme is infeasible. [ABSTRACT FROM AUTHOR]

The Cache efficiency is considered to be one of the major challenges in multi-core processors. Hence, using cache space in such processors should be meticulously managed by each of the cores. This paper addresses the issue of cache re-access and proposes an algorithm which divides the last level of cache into local and global share for the cores. The rationale behind the proposed algorithm is to activate or deactivate the ways of cache for any intended core. Consequently, the collision between cores is reduced and each of the cores can use the cache space dynamically. To simulate the proposed algorithm, the researchers used three groups of applications and the obtained results were examined and evaluated in two stages. The first phase is involved with the number of active ways in cache for each core. It should be highlighted that the proposed algorithm, in the merged state, was able to enhance the active ways up to 19%. In the second phase, cache miss rate was taken into consideration and it was observed that about 7% improvement was achieved in this stage. [ABSTRACT FROM AUTHOR]

Design of a very compact two stage amplifier is proposed by merging passive frequency compensation with a feed forward compensation technique, which achieves significant improvement in gain-bandwidth product (GBW), slew rate and phase margin with lower supply voltage requirement. The mathematical analysis given in this paper justify that the proposed technique offers the advantage of locating poles and zeros at higher frequencies than with the conventional method . The workability of the proposed amplifier has been verified by using Mentor Graphics Eldo simulation tool with TSMC CMOS 0.18 μm process parameters. The simulated results show a GBW of 150 MHz and average slew rate of 98 V/μs with a power consumption of 3.2 mW. [ABSTRACT FROM AUTHOR]

In this paper a low-noise amplifier with 0.6V supply voltage, low power consumption, and improved linearity at 5GHz is introduced in 0.18 μm CMOS technology. By using a feed-forward structure and a multi-gated configuration in the proposed circuit, linearity of the circuit is significantly improved, while only 122 μW more power is consumed compared to conventional folded cascode structure, and the other circuit parameters are similar. In addition, the Volterra series is used for nonlinear analysis and to evaluate the linearity improvement of the proposed circuit. There is also a noteworthy superiority over compared published works in the figure of merit. The suggested low-noise amplifier (LNA) at 1.28mW DC power consumption provides 9.6dB gain and a noise figure of 3.24dB. It is achieved whilst the third order interception point has been improved by 10dB and equals 0.0dBm. In the operating frequency the circuit displays satisfactory input and output impedance matching. Finally, throughout the whole circuit bandwidth input and output isolation is below −27dB. [ABSTRACT FROM AUTHOR]

Nowadays the demand for receiving the high quality electrical energy is being increasing as consumer wants not only reliable but also quality power .The usage of automated equipment are increasing and far more susceptible to disturbances compare to the prior generation equipment and information systems. With the deregulation of the electric power energy market, the awareness concerning the quality of power has been increased day by day among diverse categories of customers. Power quality has become an important topic to electricity consumers at all levels of usage. Power quality can be improved in distributed system by using shunt compensation device known as Distribution Static Compensator (DSTATCOM). This paper covers the different topologies of Distribution Static Compensators (DSTATCOMs) and the various control methodologies, and its selection for specific applications. [ABSTRACT FROM AUTHOR]

In viewpoint of technology-driven custom power apparatus, dynamic voltage restorer (DVR) is recognized as a most prominent device which can be implemented to compensate the voltage sag. On the other hand, this device has been customarily used in power distribution system to protect sensitive loads from sudden voltage sag. Owing to the restriction of energy storage in DVR's capacitors, it is essential that the active power injection by DVR to be reduced. As a consequence, this energy-saving strategy leads to the injecting the larger voltage magnitude and reactive power, shifting the phase, and cluttering the voltage wave shape. Meantime, this strategy is very sensitive respect to variation in load's power factor, so that the compensating operation will not be properly performed. In this regard, this paper suggests a flexible controller based on minimum active power strategy in order to perfectly correct the voltage sag notwithstanding variation in load's power factor. Likewise, the under-study DVR has been structured according to the cascaded H-bridge multilevel inverter topology. [ABSTRACT FROM AUTHOR]

In this paper, a new fuzzy controller for a three-phase and three-wire distribution static compensator (DSTATCOM) is presented to improve power quality. A three-leg voltage source converter based DSTATCOM is used to control the harmonic currents for two nonlinear loads. In this control system, gate pulses for IGBT switches are provided by a hysteresis controller, using samples of source voltages and currents. The derived reference currents, obtained by the direct method of reference current estimation with two PI and Fuzzy control models are simulated in a MATLAB/ Simulink environment and each performance is analyzed. Comparisons show that the fuzzy controller performs better than a classic PI controller. [ABSTRACT FROM AUTHOR]

Current starved delay elements (CSDEs) are among the popular architectures to manipulate rising or falling edges of signals in order to meet timing requirements. The digitally controllable generations of these topologies are now monotonic and reasonably power efficient, but they lack linearity in full range. Inherently, this subject may not seem problematic because by setting the dimensions of the design elements the desired delay can be acquired. However, in case that a chain of incremental delays are required, we tend to employ more linear designs. In this paper two improvements in linearity are examined for two known CS designs. Both of the topologies are in 0.18μm technology and meet appropriate design parameters like power, area and monotonic response. [ABSTRACT FROM AUTHOR]

In this paper, the influence on the voltage compensation type, active superconducting fault current limiter (ASFCL) is investigated under symmetrical and asymmetrical fault conditions. ASFCL is consisting of three air-core superconducting transformers and a three-phase voltage source converter. In the normal (no fault) state, the flux in air core is compensated to zero, so the ASFCL has no influence on the main circuit. In the case of short circuit, by controlling the amplitude and phase angle of the second winding's current, the limiting impedance which is in series with the AC main circuit can be regulated, and the fault current will be limited to a certain level. Control strategies consist of fault detection and PWM converter operation is designed. To simplify the design of controllers the mathematical equations can be expressed in synchronous rotating d-q frame. Furthermore, under the condition that the active SFCL is placed behind the relay element, its current-limiting impedance will be added into the measured impedance between the relay and the fault points. As a result, in order to prevent the refused operation of the relay, According to the two different operation modes of the active SFCL, in this paper present the corresponding two modified formulas. Using MATLAB SIMULINK, model of the three phase AC system with ASFCL is created and control strategies test, fault current limiting test, and distance relay operation is investigated. [ABSTRACT FROM AUTHOR]

Data mining has been used as a public utility in extracting knowledge from databases during recent years. Developments in data mining and availability of data and private information are the biggest challenge in this regard. Preservation of privacy in data mining has emerged as an absolute prerequisite for exchanging confidential information in terms of data analysis, validation, and publishing. The main purpose of techniques and algorithms in privacy preserving data mining is non-disclosure of sensitive and private data with minimum changes in databases so that it would not have adverse effects on the rest of data. The present paper intends to present a brief review of methods and techniques regarding privacy of data mining in association rules, their classification and finally, classification of hiding algorithms of association rules followed by a comparison between a numbers of these algorithms. [ABSTRACT FROM AUTHOR]

Meta-heuristic methods are global optimization algorithms which are widely used in the engineering issues, nowadays. The main problem with the classical optimization algorithms is their slow rate of convergence to time-consuming mathematical calculations. In this paper, a new stochastic search for optimization is presented using variable variance Guassian distribution sampling. The main idea of searching in this algorithm is to regenerate new samples around each solution with a Guassian distribution. The proposed algorithm is applied to four popular test functions for optimizations (Griewank, Booth, Rosenbrock, Rastrigin). Numerical simulations have revealed that the new presented algorithm outperformed simulated annealing and genetic algorithms. [ABSTRACT FROM AUTHOR]

In order to analyze the mathematical modeling and PID controller performance of a quadrotor, this paper firstly, describes the quadrotor flight dynamics according to “Newton-Euler laws”, then equations of motion linearized and transfer functions for 6 degrees of freedom obtained in state space domain. Classic PID controller based on “ZieglerNichols method” is designed and implemented on the system. In order to have better performance, Genetic Algorithm based on step response optimization is used to optimize PID controller performance and compared with classic method. Finally, step responses comparison for each transfer function show that Genetic Algorithm with PID control synthesis better efficiency than the classic PID controller. [ABSTRACT FROM AUTHOR]

Anti-lock braking system is designed to optimize braking procedure while maintaining automobile steerability through controlling wheels slip. However, due to nonlinearity and uncertainty of ABS structure, designing the controller for wheel slip encounters so many problems which necessitate a robust control system. In this paper, a hybrid controller is proposed for ABS to address this issue. The designed controller is a combination of sliding mode control and fuzzy control. In fact, the fuzzy system determines to switch factor of sliding mode controller proportional to automobile speed employing fuzzy rules. In this way, it would be able to avoid braking command fluctuations in lower speeds. Simulations are performed in ¼ model of automobile in MATLAB environment. The simulation results revealed the capability of proposed system to maintain slip ratio in optimal value as well as avoiding braking fluctuations in low speeds. [ABSTRACT FROM AUTHOR]

In this paper, a new control strategy for dynamic voltage restorer (DVR) is presented to compensate effectively voltage sags. In this strategy, load and supply voltage magnitude and angle are estimated by least error square filters in short time. The advantage of this method is reducing noise, distortion, and harmonic on estimation parameters. Accordingly, these parameters are controlled for each phase separately. Also, it should be noted that due to the phase angle estimation by LES filters, the control system does not require phase-locked Loop and this issue causes an increase in speed of control system response. In addition, a P+Resonant and Posicast controller are used to eliminate the steady-state error and improve transient response in DVR, respectively. The proposed control system is simulated, using PSCAD/EMTDC software by induction motors starting is connected to 13 bus IEEE standard network. Finally, the simulation results prove that the proposed control scheme performs satisfactorily under sudden changes of load. [ABSTRACT FROM AUTHOR]

Rolling mill Industry is one of the most profitable industries in the world. Chatter phenomenon is one of the key issues in this industry. Chatter or rolling unwanted vibrations not only has an adverse effect on product quality, but also reduces considerably the efficiency with reduced rolling velocities of rolling lines. This paper is an attempt to simulate the phenomenon of Chatter more accurate than the previous performed simulations. In order to increase the production speed, it needs to avoid parameters which effect on the Chatter and varieties with the rolling lines condition. Actual values of these parameters were determined in the archives of the Mobarakeh two stand cold rolling mills and collected on the 210 case study of real chattering. To simulate the experiment, a neural network is trained and weights and bias values of the neural network with genetic optimization algorithm were used to get an optimal neural network which reduces bugs on the test data. So this model is capable to predict speed of Chatter threshold on rolling process of two stand cold rolling mill with the accuracy less than one percent. So it can be used in rolling process with the building intelligent recognition systems to prevent the creator conditions of the chatter frequency range. [ABSTRACT FROM AUTHOR]

With the increasing demand for image-based applications, the efficient and reliable evaluation of image quality has increased in importance. Measuring the image quality is of fundamental importance for numerous image processing applications, where the goal of image quality assessment (IQA) methods is to automatically evaluate the quality of images in agreement with human quality judgments. Numerous IQA methods have been proposed over the past years to fulfill this goal. In this paper, a survey of the quality assessment methods for conventional image signals, as well as the newly emerged ones, which includes the high dynamic range (HDR) images, is presented. A thorough explanation of the subjective and objective IQA, and their classification is provided. Six widely used subjective quality datasets, and performance measures are overviewed. Emphasis is given to the full-reference image quality assessment (FRIQA) methods, and 9 often-used quality measures (including mean squared error (MSE), structural similarity index (SSIM), multi-scale structural similarity index (MS-SSIM), visual information fidelity (VIF), most apparent distortion (MAD), feature similarity measure (FSIM), feature similarity measure for color images (FSIMC), dynamic range independent measure (DRIM), and tone-mapped images quality index (TMQI)) are thoroughly described. Moreover, the performance and computation time of these metrics on four subjective quality datasets are evaluated. [ABSTRACT FROM AUTHOR]

This paper provides an algorithm of fault resistance compensation for digital ground distance relay considering the voltage and current transformer effects. Performance of the conventional ground distance relaying manner is adversely affected by different ground faults and also typical type, called a simultaneous open conductor and ground fault. The proposed scheme by using local-end data only, has shown satisfactory performances under wide variations in fault location, with different values of fault resistance and having positive and negative of power transfer angle. The presented method which has been carried out on the IEEE 14 bus benchmark is executed in PSCAD/EMTDC and MATLAB software, and the results show the accurate performance of mentioned configuration. [ABSTRACT FROM AUTHOR]

Most industrial processes are characterized with large uncertainties. To deal with these kinds of processes and achieve fast and accurate control in a stable fashion, the multiple-model control methods have been demonstrated to be very effective. It is difficult to build the precise mathematic model of the object and to accurately control the object with the traditional control methods. This paper applies H-infinity robust control strategies to a 24-tray separating a mixture of methanol and water. The idea has favorable controls on control targets (rise time, settling time, overshoot and undershoot, the interaction between input and output) and help on stability of the system output. Then in order to show that the proposed controller affords a good robust performance consistently we have implemented four controllers.Performance analysis of the H-infinity robust controller, Model Predictive Control (MPC), conventional PID controller and also LQG/LTR has been done using MATLAB. The comparison of various time domain parameters was done to prove that the H-Infinity robust controller has best time characteristics and in face with uncertainties has better reacts as compared to other controllers. Beside this, MPC controller has satisfied result in robust stability. [ABSTRACT FROM AUTHOR]

In this paper, a new approach is investigated for order reduction based on Legendre expansion. Harmony Search is used in this approach, to determine the reduced order model parameters. The Routh criterion is applied to specify the stability conditions. Then, the stability conditions are constraints in optimization problem. To present the efficiency of the proposed method, three test systems are reduced. The obtained results were compared to other existing techniques. The comparison showed that the proposed approach performs well. [ABSTRACT FROM AUTHOR]

This paper presents an advanced optimization technique to solve unit commitment problems and reliability issues simultaneously for thermal generating units. To solve unit commitment, generalized benders decomposition along with genetic algorithm to include minimum up/down time constraints are proposed, and for reliability issues consideration, a fuzzy stochastic-based technique is presented. To implement the problem into an optimization program, the MATLAB software, and CPLEX and KNITRO solvers are used. To verify the proposed technique and algorithm, two case studies that are IEEE 14 and 118 bus systems are implemented for optimal generation scheduling, and reliability issues. Finally, a comparison with other solution techniques has been given. [ABSTRACT FROM AUTHOR]

In this paper optimum size and location of distributed generators (DGs) are determined for maximizing voltage profile and minimizing line losses in distribution systems. For this purpose, Particle Swarm Optimization algorithm (PSO) approach is proposed. The significant innovation of this research paper is using new coding in (PSO) which includes both active and reactive powers of DGs to achieve better voltage profile improvement and line loss reduction. Furthermore, four sets of weighting factors are chosen based on the importance and criticality of the different loads. The effectiveness of the proposed method is examined in the 33 bus distribution systems. The results show that determination of optimum size and location of DGs has a considerable effect on voltage profile improvement and line loss reduction. [ABSTRACT FROM AUTHOR]

This paper presents a predictive strategy to control torque and flux of an axial flux permanent magnet (AFPM) machine. Unlike conventional direct torque control (DTC) for permanent magnet machines that only six actives voltage vectors of the inverter are used to control the torque and flux of the machine, in predictive torque control (PTC), zero voltage vectors are used to control too. Thus, the number of voltage vectors to control AFPM increases and leads to faster dynamic torque response and lower ripples of torque and flux. In predictive torque control presented in this paper, responses of torque and flux are computed for all possible switching states of the inverter at every sample time according to the discrete time model of the machine and then the switching state that optimizes ripples of torque and flux will be applied in the next discrete-time interval. Simulation results, which confirm the good performance of the proposed predictive torque control are presented. [ABSTRACT FROM AUTHOR]

In this paper, a simplified control algorithm based on unit vector template generation (UVTG) is proposed for a stardelta supported three-phase four-wire (3P-4W) unified power quality conditioner (UPQC) topology for the improvement of different power quality problems. Different topologies reported in literature for 3P-4W UPQC use active compensation for the mitigation of source neutral current along with other power quality (PQ) problems, while the uses of passive elements for the mitigation of source neutral current are advantageous over the active compensation due to ruggedness and less complexity of control. Hence, in this paper a star-delta transformer is connected in shunt near the load for mitigation of source neutral current, while three-leg voltage source inverters (VSIs) based shunt and series active power filters (APFs) of 3P-4W UPQC mitigate the current and voltage based distortions, respectively. A simple control algorithm based on Unit Vector Template Generation (UVTG) is used as a control strategy of UPQC for mitigation of different PQ problems. In this control scheme, the current/voltage control is applied over the fundamental supply currents/load voltages instead of fast changing APFs currents/voltages, thereby reducing the effects of computational delay and the required sensors. The performance of the proposed topology of UPQC is analyzed through simulations results using MATLAB software with its Simulink and Power System Block set toolboxes. [ABSTRACT FROM AUTHOR]

This paper presents a computational study on the dynamic of nitric oxide (NO) in both the biological and artificial environments, by the analysis of important nitric oxide diffusion attributes. We apply the compartmental model of NO diffusion as a formal tool, using a computational neuroscience point of view. The main objective is the analyses of the emergence and dynamic of complex structures, essentially diffusion neighbourhood (DNB), in environments with volume transmission (VT). The study is performed by the observation of the NO diffusion attributes, the NO directionality (NOD), the average influence (AI) and the center of DNB (CDNB). We present a study of the influences and dependences with respect to associated features to the NO synthesis-diffusion process, and to the different environments where it spreads (non-isotropy and non-homogeneity). The paper is structured into three sets of experiences which cover the aforementioned aspects: influence of the NO synthesis process, isolated and multiple processes, influence of distance to the element where NO is synthesized, and influence of features of the diffusion environment. The developments have been performed in mono bi-and three-dimensional environments, with endothelial cell features. The study contributes the needed formalism to management the dynamic of NO in artificial and biological environments also to quantify the information representation capacity that a type of NO diffusion-based signaling presents and their implications in many other underlying neural mechanisms, such as neural recruitment, synchronization of computations between neurons and in the brain activity in general. [ABSTRACT FROM AUTHOR]

The direct force thrust control (DTFC) is linear type of the direct torque control (DTC) method. The advantages of DTFC method are structure simplicity, low dependency to motor parameters and no requirement to coordination transformations. In this paper this method is modified in order to eliminate the defects that include the switching frequency and exciting large ripples of force and flux. In previous works, the structure simplicity of DTC, rare calculations to reduce the force ripples and fixing switching frequency are disaffirmed. With regards to keeping DTC advantages, a new method is presented in this paper to eliminate the defects by the aid of neural network. Also, the precise non-linear behavior of PMLSM motor in DTC has been considered by using space vector modulation. Finally, the simulation results concluded by the submitted intelligent DTC-SVM method are more satisfactory than other methods. [ABSTRACT FROM AUTHOR]

Jaccard index similarity measure which applies the extension principle approach to obtain fuzzy maximum and fuzzy minimum has been proposed in ranking fuzzy numbers. However, the extension principle used is only applicable to normal fuzzy numbers and, therefore, fails to rank non-normal ones. Apart from that, the extension principle does not preserve the type of membership function of fuzzy numbers and also involves laborious mathematical operations. In this paper, a simple vertex fuzzy arithmetic operation, namely the function principle is applied. This paper also proposes the degree of optimism concept in aggregating the fuzzy evidence. The method is capable to rank both normal and non-normal fuzzy numbers in a simpler manner from all decision makers' perspectives. [ABSTRACT FROM AUTHOR]

This paper describes the development of a new generation of single phase rectifier which is used to power telecommunications equipment. A rectifier is designed in such a manner to meets with all the requirements of the telecommunications industry. A number of common single phase topologies exist that could be realized as telecommunication power supplies, however, they do not completely satisfy all the industry requirements. This paper reviews recent progress in topology, control and design aspects in single phase PFC techniques. Different switching rectifier topologies are presented for various applications. Merits and limitations of these techniques are discussed. A detailed report of an investigation in the power converter system performance is also provided. [ABSTRACT FROM AUTHOR]

In this paper, the results of a finite element analysis are carried out on a new stator geometry of a three phase longitudinal flux Linear Switched Reluctance Motor (LSRM). In the new geometry, pole shoes are affixed to the stator poles. Static and dynamic characteristics for the proposed structure have been highlighted. Motor performance for variable load conditions is discussed. The 2-Dimensional (2-D) finite element analysis (FEA) and the experimental results of this paper prove that LSRMs are one of the strong candidates for linear propulsion drives. [ABSTRACT FROM AUTHOR]

The goal of this paper is to estimate the capital investment in telecom network's equipments, by using Cobb-Douglas model to predict the number of subscribers for the next years of Iran. By presenting a master plan for "fixed telephony", "mobile telephony", "data", "transmission", and "access" networks, the required equipments and also the capital investment amounts are estimated. Because of the importance of operations' support systems (OSS) in the next generation networks (NGN), the amount of required capital investment for deployment of network management systems (NMS) and customer care and billing systems (CCBS), as main parts of OSS, are calculated for the next three years in this paper. To reach these estimates, the total number of subscribers in the mentioned networks is forecasted for the period 1387-90. This assessment shows an approximate investment of M7017$ for the five mentioned networks, as the total telecom equipments' market in the country. The required investment for OSS is estimated to be M688$ in the same period. An approximate investment of M399$ and M289$ is needed for NMS and CCBS, respectively. [ABSTRACT FROM AUTHOR]

In this paper two power elements for power controller in transmission line are presented: Variable Frequency Transformer (VFT) and Rotary Power Flow Controller (RPFC). In addition, here a new Optimal Power Flow (OPF) with these elements is presented. In this paper, it has been made use of the Impedance and Admittance nonsymmetrical matrix and the matrix of loss or coefficient B are calculated in a new method. It has also been indicated that the system is not optimized if optimal power flow is not considered in locating and power of flow controller in line. The proposed method was applied to a 26-bus and 6-generator system and the results were satisfactory. [ABSTRACT FROM AUTHOR]

This paper presents a study about of a fuzzy Controlled STATCOM, which can be applied for mitigation of the voltage flicker in a distribution system. The voltage flicker is produced by a large variable load absorbing continuously changing currents such as an arc furnace. The DSTATCOM includes a voltage-sourced PWM inverter and its control system. The control strategy of the DSTATCOM plays an important role in maintaining the voltage flicker. Here, the DSTATCOM controller is designed with two types of controllers, linear proportional-integral (PI) and nonlinear fuzzy logic. The simulation of the DSTATCOM with 3MVar reactive power on a 25 KV distribution network is carried out in MATLAB/SIMULINK software. At the end of the paper, fuzzy controllers were evaluated by comparing its performance with the PI controllers. It is observed that the fuzzy controllers are very superior in mitigating the voltage flicker. [ABSTRACT FROM AUTHOR]

In this paper a new method approach is proposed for automatic segmentation of heart sounds (S1, S2) based on wavelet transform. Unlike many other approaches, this method does not use ECG as reference for detection. The applied criterion for segmentation is based on a very important physiologic attribute of heart which is the difference between the pressure of heart valves while opening and closing which causes high frequency components in heart sound. The main idea in this paper is to extract detail and approximation wavelet coefficients of heart sound (PCG) to detect the heart cycle via the Shannon energy of coefficients and then segment S1 and S2. The results show the present algorithm is capable of accurate segmentation of 90% of first heart sounds (S1) and 88.9% of second heart sounds (S2). [ABSTRACT FROM AUTHOR]

The series robot is a type of the mechanical arms with a function similar to human hands which is usually programmable. These robots, depending on the application, are designed in order to perform various operations such as clinch, welding, packaging, assembly and etc. One of the most important issues in the field of the series robots that has been highly regarded in the past few decades, is the path control. Various industries have urgent and serious need to know the optimal control of path. In this paper, the design and implementation of a series robot with two degrees of freedom and its fuzzy control is studied. This fuzzy controller, is an approach to optimal control of robot path. In these robots, finding the optimal path would be time consuming. This study uses fuzzy logic and the laws governing it, which will result the most efficient path in very little time. Then, how to use and implement Fuzzy toolbox in MATLAB software will be discussed. Evaluation of the results show that the proposed model has a higher rate than other existing models, in the field of the optimal control of robot path. [ABSTRACT FROM AUTHOR]

This paper introduces a novel ultra-wideband (UWB) microstrip antenna having wireless local area network band rejection characteristics. The proposed antenna is composed of a lip-shaped radiation patch being fed by a 50 Ω coplanar waveguide (CPW) feed line. The ground vertically continued to the two sides of the radiator. Thus, the substantial extra space adjacent to the radiator can be efficiently saved. The band rejection in the wireless local area networks (WLAN) (5.15-5.825GHz) is secured through etching the two symmetric C-shaped slots on ground plane to preclude interference between UWB and WLAN systems. The proposed antenna is of the size of 30×30×1.6mm3 working within the range of 2.9 to 11.2 GHz with VSWR lower than 2 except in 5.15-5.825GHz band. Finally, the antenna is simulated and fabricated with nearly omnidirectional radiation patterns, stable gain and constant group delay in the operating band. [ABSTRACT FROM AUTHOR]

In Iran because of the existence of Competitive market for power production, the existence of competitors in the national and international market and the policies of ministry of Power production in producing the market for producing power with the least cost; it is urgent to determine exactly the cost of power production. The first step in this regard would be to compute the cost of power production within the power station, thus it would be necessary to determine the cost of different ways in which power is produced. This would provide managers with the tools for controlling and supervising power costs and plans. In this paper, the cost of power production in the combined cycle power plant for the case Shahid Kaveh power plant of Ghaenat city will be examined. Then the cost of power production in a CHP power plant for the case of CHP power plant in Gonabad belonging to Sanat Yaran Energy Fadak Ghadr has been studied. Eventually, comparing power production costs in combined Cycle Power Plant with CHP power plant, it has been concluded that a CHP power plant is superior to a combined Cycle Power Plant in efficiency, power tolls, power quality and etc. [ABSTRACT FROM AUTHOR]

The main contribution of this paper is proposing a novel deterministic and non-iterative clustering algorithm for automatic Farsi license plate recognition (ALPR). In fact, after discarding some regions with low probability in terms of being license plate, the edge points inside every separately remained region are considered as a cluster and a Gaussian component is estimated using expectation-maximization (E-M) algorithm, for every cluster. Candidate regions are obtained by applying application-oriented thresholds for size, aspect ratio and orientation to Gaussian components. Then the license plate regions are identified by counting regions like to numeric characters, exploiting maximally stable extremal regions (MSER) detector whereas numeric characters are extracted by using a proposed algorithm, for discarding non-character regions. So, the algorithm is able to segment the license plate numeric and alphabetic characters simultaneously. Finally for character recognition, a new simple, fast and robust algorithm, which uses feature extraction and template matching technique, is proposed. The method is evaluated for detection and recognition, by using an Iranian image database that includes access control (AC), law enforcement (LE) and road patrol (RP) applications. The method is robust to rotation, skew, and multiplicity of license plate and low quality and complex background images. [ABSTRACT FROM AUTHOR]

The topic of power allocation in multiple-input-multiple-output )MIMO( systems for wireless communication in order to reach high capacity or low bit error rate has gained some attention. In this paper, heuristic algorithms, including genetic and particle swarm optimization algorithms, are applied to find the optimal power allocation for achieving best capacity benefit. Two cases of un-polarized and cross-polarized antennas of spatial MIMO channel modeling are studied. We demonstrate that the performance of genetic and particle swarm optimization algorithms is optimal compared with a perfect search at a reduced computational complexity. These algorithms have fast convergence and can handle large number of sub-channels without performance degradation. Both simulation and numerical results confirm that, compared to other mathematical methods, the proposed algorithms are more efficient in terms of complexity and power assignment to antennas in a MIMO system. [ABSTRACT FROM AUTHOR]

A photovoltaic (PV) power generation system under partial shaded conditions (PSC) exhibits multiple power peaks in the power-voltage (P-V) characteristic curve and traditional optimization methods fail to detect the global maximum power point (GMPP). This paper proposes a hybrid intelligent to improve the maximum power point (MPP) tracking capability for PV system under partial shading condition. The key advantage of the proposed technique is the elimination of PI control loops using direct duty cycle control method. Furthermore, since the proposed method is based on optimized search method, it overcomes the common drawback of the conventional MPPT, i.e. To evaluate the idea, the algorithm is implemented on a boost converter and compared to the conventional MPPT methods. Simulation results indicate that the proposed method outperforms others method in terms of global peak (GP) tracking speed and accuracy under various partial shading conditions. Furthermore, it is tested using data of a tropical cloudy day, which includes rapid movement of the passing clouds and partial shading. [ABSTRACT FROM AUTHOR]

The growth of technology in suspension systems have led the magnetic bearings to a more powerful and economical design. Such bearings have lots of benefits such as performance capability in high speeds and the ability to perform action without lubrication in different performances that causes a decrease in the environmental and system pollution and makes it possible to work in vacant environments. Magnetic bearings work without friction and have little attrition. In This paper, the operation of magnetic bearing with 8 and 16 polar at a velocity rate at 30000 rpm and gap tolerance ranging from 2 to 0.5 mm are evaluated. The magnetic force condition is simulated based on finite element by optimizing the best mesh measurement. [ABSTRACT FROM AUTHOR]

In restructured electricity markets, the consumers have various procurement strategies to supply their electricity demand from alternative resources such as self-generating facility, bilateral contracts and pool market purchase. A hybrid approach based on binary particle swarm optimization (BPSO) and binary imperialist competitive algorithm (BICA) is proposed in this paper to find optimal procurement for large consumers with multiple procurement options. The solution of these problems provides adequate information to obtain an electricity procurement problem for large consumers. Also, the results are compared with ICA and PSO methods. Test results show that the proposed hybrid approach is more effective and has higher capability in finding the optimum solutions in comparison with ICA and PSO methods. A case study is used to illustrate the efficiency of the proposed hybrid approach. [ABSTRACT FROM AUTHOR]