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In this paper, the air flow around a root airfoil model of horizontal axis wind turbine, namely SG6040 is numerically simulated using finite volume method by three turbulence modelling k-ω, k-ω SST, and Spalart-Allmaras in two Reynolds Number of 137,122 and 149,969 and at 0 to 10 degrees angles of attack. The main objective of this paper is to provide a proper numerical model for simulating the root airfoils of wind turbines with small rotor sizes. Also, the effect of angles of attack and Reynolds number on aerodynamic coefficients were investigated and the results were compared with each other. The results show that the k-ω SST turbulence model presents better results than other models and is more consistent with experimental results. Also, by increasing Reynolds number, turbulence models seem to have the same trend and the greatest differences occur in the low Reynolds numbers. The results obtained in this case study can play a significant role in designing wind turbine blades.

This paper discusses the stability analysis of fractional-order polynomial systems by using the sum of squares method. furthermore the feasibility of designing the problems demonstrates which can not be represented in LMIs. unlike the T-S fuzzy model which can only work with fixed matrices, this method deal with polynomial matrices. Therefore, displaying a nonlinear system model using polynomials is a more efficient way. The stabilization of fractional order systems based on the fuzzy T-S model is expressed according to Lyapunov theory of stability by linear matrix inequality (LMI) while stability analysis polynomial fuzzy is based on the sum of the square. The main advantage of the method is the stabilization of fractional order systems based on the fuzzy T-S model. the stabilization conditions are expressed according to Lyapunov theory of stability by linear matrix inequality (LMI) while stability analysis is based on the polynomial fuzzy model. the systems where LMI optimization methods do not work, stability analysis and controller design can be performed by SOSTOOLS. In this paper, the stability conditions of a fractional-order polynomial fuzzy system are investigated then obtained necessary and sufficient conditions for stability. Finally, shown an example of the accuracy and The correctness of the proposed method.

This paper designs a robust control system for wind turbines using a fuzzy sliding mode controller. Due to the increasing use of wind turbines and the importance of reliability and efficiency of these systems, in this paper the tolerance of wind turbine system using a combination of classical nonlinear and intelligent control methods against the occurrence of possible faults has been investigated. The wind turbine system based on the permanent magnet synchronous generator has been studied in this paper. In the design of the fault tolerant controller, a combination of the sliding mode controller based on advanced exponential acquisition law and fuzzy system is employed and the control goal is to track the reference input when the system is under fault conditions. Also, the designed controller is able to reduce the chattering phenomenon. To evaluate the performance of the proposed control system, simulated faults with different characteristics such as amplitude, occurrence time and dynamic change speed have been developed. Results confirm that the designed controller is robust against to actuator faults in the wind turbine system. Also, the output voltage is perfectly set to the constant reference value.

In this paper, the effect of installing a hybrid superconducting fault current limiter on the apparent impedance seen by the distance relay in power systems compensated with STATCOM has been analyzed. The STATCOM is installed in the system to meet the increase in electricity demand and increase the capacity of the transmission line. Installing STATCOM in the system increases the level of short circuit current, which is recommended to use HSFCL to control this current. Installing STATCOM and HSFCL changes the amount of impedance calculated by the distance relay. The STATCOM location can be before or after the fault location. Its location and distance from the relay have effect on the performance of the protection systems. The HSFCL location, can be before or after the voltage transformer has effect on the performance of the protection systems also. The fault type, fault location and fault resistance are other parameters that have been investigated in simulation studies. The HSFCL has two structures, RHSFCL and LHSFCL, both of which have been studied in this paper. The two modes have been compared also. The system is modeled and simulated with different equipment in PSCAD / EMTDC software and the results are discussed.

In this research, an optimal energy management model of a residential microgrid with the aim of resiliency and flexibility improvement is presented. Accordingly, a residential microgrid consisting of a solar power plant with energy storage system is considered. Each of houses in the microgrid has an electric vehicle. The residential microgrid is connected to the main grid and has been equipped with smart grid infrastructures. The outage of the main grid causes load shedding that consequently reduces the resiliency. Keeping the security of supply during these distortions is necessary. Therefore, in this paper, a new model of microgrid operation based on solar power plant and energy storage system is proposed. The efficiency of the proposed model is evaluated through numerical calculation of resiliency using a new index proposed in this paper. In addition, the proposed model improves the system flexibility. The amount of this improvement is evaluated using practical and accurate indicators including self-consumption and storage efficiency. The results show that the proposed model improves the resiliency in off-peak and peak hours by 4.7% and 9.75% respectively. Moreover, two indexes of flexibility, including self-consumption and storage efficiency, improve by 9.1% and 2.2% respectively.

This paper presents a graphene-based polarization-insensitive metamaterial perfect absorber at terahertz frequency range. The absorber consists of a graphene pattern layer at the top of the structure, a dielectric spacer layer, and an Au layer at the bottom of the structure. In the proposed structure, the ability of perfect absorption is investigated by the complete suppression of radiation and reflected light and the complete dissipation of incident energy. At the first, the proposed structure and its design process are verified and it is shown that in the three bands, the results of perfect absorption at frequencies of 2, 2.95 and 3.75 terahertz are achieved with absorption rates of 93.5%, 99.8% and 98.1%, respectively. Also, the physical mechanism of structure performance is investigated by the surface distribution of the electric field, as well as the geometric changes of the structure. In addition, the design of the proposed structure with graphene provides this advantage so that the resonant frequency can be adjusted by changing the Fermi energy level and graphene relaxation time without changing the proposed structure again. With the study, it is found that the proposed metamaterials perfect absorber is not sensitive to polarization and is more tolerant to the angle of incident radiation. Accordingly, the proposed broadband absorber in this paper has potential in imaging, detection, filtering, solar tracking and other applications.

Due to the carcinogenic nature of diesel particles, these particles will pose a serious threat to human health. In order to meet this challenge, the attention of researchers and government agencies around the world is focused on achieving an economical and safe technology to control these particles. Given that electrostatic precipitators are one of the most important treatment technologies, this paper deals with the mathematical modeling of a cylindrical electrostatic precipitator and the prediction of the collection efficiency of diesel conductive particles in its various conditions. This sediment consists of a grounded cylinder with a circular cross-section and an excited electrode with negative direct current voltage installed in the center of the cylinder. Using the analytical response of Poisson equations and current conservation, ion spatial charge density, electric potential distribution and electrical volume forces in the electrostatic precipitator channel will be calculated. In this paper, COMSOL software is used for three-dimensional modeling of cylindrical electrostatic precipitators and solving turbulent air flow equations considering volume electric force. The particle charge and motion equations have been implemented in COMSOL software using particle routing physics and the results have been analyzed.

Multi-level inverters (MLIs) have made great strides in the use of renewable and industrial energy compared to conventional two-level inverters in terms of output voltage quality, filters and high efficiency requirements. This paper describes a new topology for single-phase multi-level invereter. This topology is presented with the aim of reducing the number of isolated voltage sources, switches and drivers that are able to modularly increase the number of output levels. The proposed structure has been improved to achieve a higher number of output voltage levels relative to the number of switches, drivers and DC voltage source. To confirm the superiority of the proposed structure, a detailed comparison has been performed with other multi-level inverter topologies. In this paper, the Nearest Level Modulation (NLM) is used to generate the output voltage and is simulated in Matlab/Simulink environment. The performance of the designed structure is comprehensively evaluated in symmetric and asymmetric topologies.

The use of multi-unit cubic satellite (CubeSats), designed nowadays, in accordance with a certain standard, have made any research aimed towards their optimization, quite significant. In the present paper, studies one such common satellite design structure known as “1U”. Our study is carried out with a focus on the structure subsystem, which is of high consequence, due to the direct relationship, it would establish with other subsystems. Informed by the conditions, such satellite structure is exposed to, the present paper, defines the dynamic equations governing its motion, as well as relevant heat, modal and static equations, and utilizes the finite element method (FEM), in several separate portions to solve them. To attain a higher accuracy, our study takes into account, the standards and design specifications for such satellites. Analysis indicate temperature variations on the outer structure of the satellite is in a range from −19.79°C up to 18.85. Moreover, the highest stress value taken by the satellite structure is 45.42 MPa, demonstrating structural resilience versus stress excreted. The first mode of satellite structural resonance is 467.647 Hz. reliability factor was obtained as well, from an investigation of stress values inside the structure. Put together, the results from the analyses have allowed us to conclude that the structure, is in fact resilient, against the excreted stress. Supplementary output from the present study is also valuable, in provision of various prerequisites to an optimal design of the structure subsystem, as well as several other subsystems.

After a comprehensive study of voltage unbalance issue, this ‎paper presents the defects of some unbalance factors and ‎concentrates on the importance of considering the angle of ‎complex voltage unbalance factor (CVUF) in order to ‎unbalanced condition assessment. Then, for the sake of precise ‎analyzing of the steady state performance of the induction ‎motor (IM) under unbalanced condition, the paper concentrates ‎on the complex current unbalance factor (CCUF) that consists of ‎complex voltage unbalance factor and impedance unbalance ‎factor (IUF). Therefore, the method considers the effects of ‎induction motor parameters as well. Because, the induction ‎machine parameters affect the performance of the induction ‎motor under unbalanced condition, complex current unbalance ‎factor gives a precise estimation of the electromagnetic torque ‎and the output power of the motor. In this paper, the ‎improvement of the steady state performance of an induction ‎motor under unbalanced condition by coupling small sized ‎induction motors instead of a large one is proved.‎

In this paper, 3D numerical lagrangian modelling of flow was performed using Weakly Compressible Smoothed Particle Hydrodynamic (WCSPH) method. Navier Stokes and Euler Equations were used to simulate viscous and inviscid fluid flow respectively. The fluid flow was assumed in three forms of inviscid, with artificial viscosity and viscous fluid flow with turbulence. Although the WCSPH method is acceptable for simulating of free surface, but has a major problem of large and non-physical oscillations in pressure and velocity field. In this paper the effect of density filtering, conservative and non-conservative Riemann solvers were studied for correction of pressure and velocity of WCSPH results. Furthermore due to using of laminar and SPS turbulence method with non-conservative Riemann, the effect of using kernel gradient correction was also studied. Therefore five numerical methods were introduced for simulating 3D incompressible fluid flow. The results of these numerical models were compared with experimental data. The comparison showed that using Riemann solvers and especially non-conservative Riemann solver with kernel gradient correction gives acceptable results for pressure and velocity field of numerical results. Finally the validation of numerical model was also performed for the variation of free surface.

Recent advances in information technology and the need for more security have led to the rapid development of intelligent biometric identification systems. Recent studies have proven that handwriting of each person is unique and can be used as one of the authentication methods. There are many researches in the literature for writer identification on a specific language. Unfortunately, there are no necessary data sets for this purpose. In this paper, for the first time, a handwritten data set of 300 persons in both Persian and English languages was collected. The main goal of this paper is to provide a model to identify the writer independent of the language written in Persian and English. After pre-processing stage, each person's handwriting is converted into blocks of a certain size called a texture. Then, using these textures, the desired features are extracted. In order to extract these features, first a two-dimensional wavelet transform is applied to each image and then, using the new algorithm for calculating the fractal dimension, which is used for the first time in this field, the feature vector is obtained. Finally, MLP neural networks are utilized for classification step. The performance of the proposed method is evaluated in different scenarios.

Permanent magnet synchronous motors due to its high efficiency and power density, reliable performance and simple construction, industrially used. One of the problems with these Motor need accurate information to control its speed and position. Recently, because of the difficulties of the speed sensors, speed estimation is used instead of measuring it. In this paper, the state dependent model reference adaptive controller based on pseudo linearization is used to control the permanent magnet synchronous motor that its parameters are determined based on Lyapunov theory. This controller show good results by production control law, despite changing circumstances and maintain system stability despite external disturbances. Also due to uncertainty in the estimation of the position and speed of motor parameters, high impact, online identification of these parameters is necessary. In this paper, adaptive augmented observer is used to estimate speed and identify motor parameters online. The main advantage of this estimator is that speed and load torque estimation and identification of parameters are simultaneously thus volume and time calculations are reduced. The simulation results show convenient tracking of desired speed with the load torque, changing the motor parameters and the speed reference.

In this paper, an ultra-wideband (UWB) bandpass filter is designed by using the stepped impedance method. A stepped impedance structure with low order is proposed, then some of them are used in series. First only one short circuit stub is used then some of them are combined according to frequency response. The result of simulation depicts that the passband is 3.356 to 22.81 GHz, it means bandwidth is over than 19 GHz, therefore the fractional bandwidth is 148.7%, which it is good compared to papers of recent years. Ripple is less than 1dB in band. The insertion loss is over than 25 dB in out of band. The presented filter size is 16×16 mm2 that it is compact. The designed filter is fabricated on RO4003 substrate with 3.38 dielectric constant, 32 mil thickness, and 0.0026 loss tangent. The simulation is performed with numerical software and they confirm each other's results.

In this paper, a detailed modeling of energy consumption in the processes of producing aluminum and cement industrial units based on the linear piece-wise approximation (LPWA) method is presented. The presented model has been implemented in the day-ahead energy management planning of a microgrid including these industrial units. In order to increase the profit of the mentioned industrial units, the demand response programs are implemented and therefore these units are able to participate in the energy and ancillary services market. The energy management planning proposed in this paper, considers the exact model and all constraints of the industrial units and microgrid in order to maximize the profit of the microgrid and these units. The performance of the model and the proposed planning has been evaluated through two case studies, with and without implementation of demand response programs. In addition, the effect of the changes in the profit obtained by selling the product of each industrial unit and the prices of sold energy by microgrid to the electricity market, on the profit of the units and the microgrid, have been examined using the sensitivity analysis. The obtained results, besides validating the proposed model, show that the implementation of demand response programs and the participation of industrial units in the energy and ancillary services market, not only modifying the demand curve but also increase the profit of the microgrid and units.

In this paper, the geometry of a frog- shape MEMS microphone is optimized using a particle swarm optimization technique to reduce bias voltage and to increase sensitivity. The PSO algorithm is a population based stochastic optimization technique that inspired by social behavior of bird flocking, which is used to solve complicated design spaces and multi physical problems. The proposed method in this paper can be adapted to a variety of MEMS device designs. This approach shows improvements over previous designs that were generated from the conventional design approach (approximate methods based on trial and error). Considering that the performance of the microphone is studied in different directions, and various design parameters are in a trade off with each other, the definition of a multi-purpose target function is very important. In this work, we define the target function such that all three factors of resonance frequency, mechanical sensitivity and pull-in voltage should be considered, simultaneously. The results show that the designed microphone has a good performance. Actually, only by choosing optimal dimensions for length and width of frog-shape diaphragm arms, the mechanical sensitivity and open circuit sensitivity of the microphone increased approximately 4 and 2 times respectively, and the pull-in voltage decreased to half approximately.

Acne is a common skin lesion which controls the quality of life. Skin analysis is one of the important steps before starting treatment. previously, this detection has been done manually, which cause different results by the various dermatologist. Today, the detection of skin lesions is done automatically, which leads to a more accurate diagnosis. In this paper, the locating and counting of skin lesions is done using Fuzzy Logic algorithm. Although many studies are done to detect the skin lesions, but the results of each method usually take a lot of time. Therefore, one of the advantage of proposed method is in processing time and then data cluster, which the ISODATA method is used. The images used in this study take from the Visio Face Machine, which has no effect to the skin’s texture, and are used in the training phase of system. Given that these images are in RGB color space; colors can be displayed in HSI color space in more details. For lesion detection and feature extraction, Fuzzy Logic algorithm and HSI color space are used. But the purpose of this paper is to build a robot, which burn lesions by Plexr Plus machine automatically. In test phase, using RGB color space and depth sensor of Kinect camera, three dimensional location of lesions are identified. Finally, the average of accuracy, precision and sensitivity were 99.4, 88,2 and 51 respectively.

This paper investigates the effect of the area of the horizontal stabilizer of a single-main-rotor helicopter on its dynamic responses, stability properties, and flight handling quality during forward flights. Taking linear aero-dynamical relations into account, and assuming a linear induced velocity for the rotor and two degrees of freedom of flapping and feathering for each blade, we have derived the six degrees of freedom nonlinear dynamical model of the helicopter consisting of a main rotor, tail rotor, horizontal stabilizer, vertical stabilizer, fuselage, and the thrust system. The paper covers our findings on the stability derivatives, the effect of the area of the horizontal stabilizer on the forward-flight stability of the helicopter. The results indicate that the trim flight conditions do not considerably change when the horizontal stabilizer area increases. Moreover, increasing the area of the horizontal stabilizer threefold has been found to improve the longitudinal stability of the helicopter—the poles of the open-loop system are transferred to the stability region. However, such stability is accompanied by a favorable overshoot and the settling time required for flight at level 1(ADS-33E); (overshoot less than 30% and the settling time less than 5 seconds.)

In Recent years, it has been mentioned that the Transmission Expansion Planning is an effective way to mitigate the cascading failure impacts in transmission network. Also, solving transmission expansion planning with cascading failure issues via analytical and assessment approach instead of optimization approach causes that the impacts of cascading failure are more effectively mitigated. The Analytical and assessment approach offers a set of critical lines as a suitable candidate placement of new lines. However, installing new lines for all of elements of the set of critical line is an impractical and uneconomical way. In order to overcome this drawback, a new method is proposed in this paper. The proposed method is based on introducing a vulnerable area in transmission network instead of providing a set of critical lines. The vulnerable area is provided via finding the most vulnerable line and considering a bus farther way (adjacent bus) strategy. All of possible transmission expansion plan at this area are considered to find the best transmission expansion plan. Moreover, a transmission network solidification index based on transmission network vulnerability index is proposed in this paper to rank the possible transmission expansion plans at the vulnerable area. The efficiency and feasibility of the proposed method is investigated at IEEE 39-Bus test system. The numerical results show that using the proposed approach is able to mitigate cascading failure impacts in transmission network.

In this paper, a five-level pharmaceutical supply chain network is modeled under uncertainty. Levels of this pharmaceutical supply chain network include raw material supplier, production center, distribution center, Health centers and customers. Also, the objectives of this paper include minimizing the costs of the total supply chain network, minimizing the maximum unmet demand, and maximizing reliability in timely delivery of drugs, by considering the perishable time and the discount on the purchase of raw materials. Decision-making variables are divided into two strategic and tactical categories and, include determining the optimal number and location of potential facilities and determining the optimal amount of drug flow between the selected facilities, respectively. A robust-possibilistic optimization method has been used to control the uncertain parameters, and the hybrid LP-metric method and Monte Carlo simulation approaches have been used to solve the multi-objective model. Finally, by providing a numerical example, the outputs obtained from the solution of the model have been discussed.

In this paper, a new mixed integer mathematical model is developed for desifning a sustainable closed loop supply chain management problem. In this model, some real world manufacturing features are taken into account like exonomical, environmental and social responsibility indexes. The main novelty of propose model the consideration of three key indexes of local and sustainable job opportunities and also creating new job opportunities in terms of social responsibility of a supply chain. Moreover, the greenness of a supply chain in terms of CO2 emmisions are investigated through the developed model. In order to evaluate and validate the proposed mathematical model, some numerical examples are generated randomly, and solved using the CPLEX solver on Gams optimization package. In addition, some magerials insightsd are included in the paper by performing deep sensitivity analysis of the esseintial parameters. Based on obtained results, considering all sustainbiliy aspects of a supply chain in a concurrent way can reduce costs, significantly.

In a smart home, all its internal components interact with each other through an integrated system and environmentally reasonable logic. In this house, energy management (EMS) can play a role in reducing energy costs. Therefore, in this paper, given the increasing importance of this discussion, the operation of smart home with the presence of electric vehicles with the capability of exchanging power with the network, the Energy storage system and solar panels have been modeled and evaluated in the framework of mixed integer linear programming. In this paper Various studies including the sale of electrical energy produced by solar panels to power grid, Loads with time-consuming movement such as washing machines as well as various demand response strategies based on energy price have been considered to evaluate the economic and technical effects of electric vehicles, energy storage batteries And solar panels. In assessing the performance of solar panels, uncertainty regarding the prediction of solar power is considered, and the proposed model has been analyzed by considering the conditional value at risk (CVAR) criteria. The proposed model is implemented in the GAMS software and the results indicate that the use of additional power systems will significantly reduce the cost of smart home power.

This paper presents a new approach to optimizing of the control strategy in parallel hybrid vehicles. By proposing a new objective function and in order to efficient management of the power split between the combustion and electrical motors, fuel consumption and the amount of emissions are minimized with considering the penalty functions. Using the ADVISOR software, as one of the most common software used for a hybrid vehicle, as well as nonlinear equations of these vehicles, a parallel hybrid vehicle in the urban driving cycle of the United States is simulated. In this paper, an extended algorithm based on the Particle Swarm Optimization (PSO) is used. In the proposed PSO algorithm, the coefficients of contraction and the mirror effect of speed are used to increase the efficiency of the method. With the new constraints proposed for the PSO algorithm, the results have been improved. Also, simulation results are compared with the results obtained from the algorithms presented in recent papers. This comparison also shows the efficiency and accuracy of the proposed algorithm in optimizing the control parameters that lead to reduced fuel consumption and emissions from the vehicle.

In the present paper, numerical simulations of laminar forced convection flow and entropy generation analysis in a 2-D duct with two sudden expansions are investigated. These two expansions are created by four inclined backward facing steps and beget the separation flows and vortex regions. The vortex regions have the significant effects on the heat transfer rates and flow irreversibility. The inclination angle of steps is one of effective parameters on the control of the separation flows, heat transfer rates and flow irreversibility. In this paper, after calculation of velocity fields and temperature distributions, the effect of the step inclination angle on the separated flows, Nusselt number, friction coefficient, entropy generation number and Bejan number is studied. To obtain the temperature distributions and velocity fields, the set of governing equations including mass, momentum and energy equations are solved by the finite volume methods and computational fluid dynamic (CFD) techniques. For simulating the inclined surfaces of steps in Cartesian coordinates, the blocked-off method is used. Also, thermodynamic second law analysis is employed to calculate the entropy generation and flow irreversibility. Finally, the effect of the Brickman number on the entropy generation number and Bijan number is investigated graphically.

The conventional boost and buck boost converter have low voltage gain. The voltage gain of the conventional converters is limited considering the issues such as parasitic resistance and because of this issues, high step up dc-dc converter must be used. In this paper, new transformerless high step-up buck boost and boost converters with low stress on the switch are proposed. In this converters only one active switch are used, which makes the control scheme simple as well as reducing the switching power loss. The voltage gain of the proposed converters is higher than the conventional boost and buck boost converters. The proposed converters expand the continues conduction mode (CCM) operation region . Proposed converters have low voltage stress on the active switch, low conduction loss and high efficiency. The proposed converters can be operated in the continuous conduction mode (CCM) and the discontinuous conduction mode (DCM). In this paper, different operation modes of the proposed converter, calculation of the voltage gain, the currents that flow through the components and efficiency are provided. To prove the correct operation of the proposed converters, simulation results in PSCAD software are provided.

By increasing the speed of data generation, need to process, store and analyze of Big Data becomes increasing. Related work has been done to create real-time data warehouse, but according to current unstructured data in Big Data, data warehouse with the old structure, it doesn't answer new management requirements of this type of Data. Recently, Data Lake has been proposed for unstructured data (with BASE properties). However, existence of important structured data (with ACID properties) and less sensitive unstructured big data on the other hand, causing new problems in the management of Big Data by using of this methods. In this paper we will offer a solution which is able to store structured data and unstructured data simultaneously and it can response to user’s queries in real-time. As one of the important results of this research, after comparing the data warehouse and Data Lake concluded that the lake is not a replacement for a data warehouse, and data warehouse has particular use, especially in financial data; because the data warehouse compliance ACID theory, and Data Lake cater requirements of BASE theory. The raised idea in this paper has three main advantage: 1- Simultaneous use of data warehouse and Data Lake to meet the needs of the organization data with the benefits of them. 2- Separating new data from old data to achieve real-time. 3- Development parallelism, thus synchronization loading data and query processing to reduce the cost of time.

This paper focuses on the study of Laminar mix convection heat transfer of water-AL2O3 and water-CuO nanofluids whit temperature and nanoparticles concentration dependent thermophyscical properties in a rectangular shallow cavity was investigated numerically. Upper movable lid of the cavity was at a lower temperature compared to the bottom wall. Simulations were performed for Grashof numbers of 104 for Richardson numbers from 0.1 to 4.5, and nanoparticle volume fraction of 0.01-0.04. The two-dimensional governing equations were discretized using a finite volume method and SIMPLE algorithm. The model prediction for very low solid volume fraction were found to be in good agreement whit earlier numerical studies for a base fluid. It is shown that under a wide range of volume fraction of nanoparticles and different Richardson number, the enhancement of heat transfer will be evaluated. The Reynolds number varies due to variation of the Richardson number. Heat transfer was elevated by increasing the concentration of nanoparticles additionally. In this paper investigated the role of nanofluid variable properties in differentially heated enclosures and found that the prediction of heat.

In the grid-tied PV inverter systems, the design of a proper power conditioning system is an important issue to ensure high-quality power injection to the grid. In the low-voltage distribution network, the grid impedance variations change the resonant frequency of LCL filters. The capacitor current feedback active damping is one the most effective procedures to suppress the resonance of LCL filters. In this paper, A proportional-integral (PI) capacitor current feedback active damping method with positive virtual impedance shaping is proposed. Utilizing the proposed control strategy, the stability of the grid-tied PV inverter system against changes in grid impedance is well maintained. In addition, the system offers good performance against the PV power variations. In order to track the maximum power point, the incremental conductance (IC) procedure along with an integral regulator is utilized. Simulation of the overall system also includes solar panels, maximum power point tracking algorithm, DC-DC boost converter as well as an inverter, and LCL filter to model the grid-tied PV system with the most possible details. Simulations are carried out in MATLAB/Simulink, and it has been proved that the proposed control system maintains its stability against grid parameters variations.

Classification of isolated digits is a fundamental challenge for many speech classification systems. Previous works on spoken digits have been limited to the numbers 0 to 9. In this paper, we propose two deep learning-based models for spoken digit recognition in the range of 0 to 599. The first model is a Convolutional Neural Network (CNN) model that uses the Mel spectrogram obtained from the audio data. The second model uses the recent advances in deep sequential models, especially the Transformer model followed by a Long Short-Term Memory (LSTM) Network and a classifier. Moreover, we also collected a dataset, including audio data by a contribution of 145 people, covering the numerical range from 0 to 599. The experimental results on the collected dataset indicate a validation accuracy of 98.03%.

In many real-world applications, data is dynamic and noisy. In such a situation, anomaly detection should be performed with an online and robust model against noise. In recent years, recurrent neural networks have been used on data sequences and have achieved good performance in this field. The existing methods do not have sufficient robustness against noise. This paper presents a method for anomaly detection in dynamic graph data using recurrent neural networks that are robust against noise and have sufficient adaptivity to changes in the data pattern. The proposed robust recurrent neural network extracts and introduces anomalies for the purpose of noise management. At the same time, it learns the original patterns in an online manner and is adapted to the changes. To evaluate the proposed method, some experiments are presented that measure its ability in anomaly detection in addition to the learning and adaptation ability in comparison with the existing methods. The results have confirmed the superiority of the proposed method.

This paper presents a finite control set model predictive control for a four-level nested neutral point clamped converter (4L-NNPC) in electric drive application. Controlling the voltage of the flying capacitors (FCs) in this converter, especially at low output frequency, is challenging due to the lack of complete switching states to control the FCs voltages. In the proposed method, the main control objectives of the electrical motor and converter, i.e., the control of the torque, flux, and voltage of the FCs, have been formulated. A modified weighting factor for FC voltage objective in the cost function is introduced, which provides the full possibility of controlling voltage fluctuations of FCs, especially in low-frequency operation. The proposed control method, in addition to controlling the electric motor's required objectives, can control the voltage of the FCs of the converter in the entire operating frequency range. The performance of the proposed method has been simulated and verified on a 4L-NNPC converter using a 1500 HP, 4160 V electric drive in the MATLAB/Simulink software environment.

Multi-level inverters (MLIs) have now become an essential component for medium and high power applications with medium voltage levels. Low switches multi-level inverters are very popular due to their high efficiency, low cost, and easy control for output with higher levels. In this paper, a new multi-level inverter structure based on a switched DC voltage source is proposed by reducing the number of switches for single-phase applications. The proposed structure can be used in grid-connected applications, such as grid connections for renewable energy sources. The proposed structure is developed with a higher number of levels at the output using a smaller number of devices. The proposed topology can also be used in symmetric and asymmetric configurations. Two switching methods including pulse width modulation (PWM) switching and ladder switching based on selective harmonic elimination (SHE) have been used to generate the output voltage. Comparative studies with multilevel inverters were presented recently to show the advantage of the proposed structure in terms of reducing the number of devices. Simulation and experimental results are presented to confirm the performance of the proposed topology. In addition, the performance of the proposed multilevel structure for energy transfer from renewable sources to the low-power grid has also been investigated.

The use of renewable energy has recently become very common in most countries of today's society. Among these renewable energies, wind energy is one of the most attractive methods of mechanical energy production, and different methods of flow control, including active, semi-active and passive, have been investigated by various researchers. To control the fluid flow in an active way on the wind turbine blade, the corona discharge actuator based on plasma is considered the most appropriate method to reduce the fluid flow separation on the wind turbine blade. In this paper, we present a numerical simulation to integrate active load control using a corona discharge based on plasma actuators over the roughness blade. Effects of roughness, actuators voltage and frequency on aerodynamics parameters such as separation point, lift and drag coefficients have been showed. Present results showed that, the lift coefficient increase with increase in the voltage and frequency of plasma actuators. Overall, using the roughness for outer surface of blade would decrease the critical pressure coefficient by approximately 50% compared to that for the smooth surface.

In this article a method for determining the admissible acceleration of the end-effector is presented for the suspended cable robot in the different points of the workspace. The presented acceleration analysis is different with the dynamic work space. Indeed, the dynamic work space is defined as the set of all end-effector poses satisfying the acceleration conditions. While in the proposed analysis in this paper, the allowable acceleration range of the end-effector in each direction is obtained for any point of the workspace. To this end, after deriving the kinematic equations of the four-cable suspended robot, its dynamic equations are derived using the Lagrange method. Then, on the base of the positive tension constraint in the cables and the torque constraint of the actuators, the obtained equations are simplified to obtain the simple relation between the constrains and the end-effector acceleration in such a way that the lower and upper limit of the admissible acceleration is obtained. Some simulations are done in order to present the admissible acceleration in different point of the workspace. The simulation results show that the acceleration range is in the form of the pyramid with the rhomboid base. So the allowable range of the acceleration is changed in different direction. The results obtained in this paper can be used for online trajectory planning in high speed motion of cable robot.

Service-oriented architecture is one of the fields of software engineering that enables a connection between the two systems in a heterogeneous network with different technology. Architectural features include the ability to reuse and agility against future changes. In the service-oriented architecture, one of the most important and fundamental challenge is that despite various code generators that introduced in this field, there are still shortcomings in the various phases of the code generator. In this paper, due to the weaknesses of the code generators in the different phases and that these shortcomings be found in the quality, and production software systems, have to offer a hybrid approach for the introduction of two references to the code generator. In order to use the advantages of the above two code generator, a hybrid code generator (SOG) is offered. Also, in order to increase the efficiency in the production of software systems using the provided code generator, the new features to enhance the security the code generator, increase programming languages supported, multiple formats for the transmission of information between client and server, adding a cryptographic layer and the production of panels for database management is provided on the web. The main objective of this paper is the code generator provides the codes related to service-oriented architecture. In order to assess the ability of the proposed code generator, the code generator is evaluated based on criteria related to different protocols and data transfer between client and server.

This paper divided into two parts. In the first part various type of technology for texturing of sheet rolled metal Is introduced including, shot blasting (SB), laser beam texturing (LBT), ion beam texturing, electron beam texturing (EBT), and electrical discharge texturing. Advantages and disadvantages of various type of texturing are discussed and compare with each other. In the second part of the paper, an expert system is modeling and developed for estimating surface roughness and peak count in concurrent engineering environment for electro-discharge texturing (EDT). The expert system links with A feature based CAD system in order to extract design data. Description of different size and classes of sheet rolled material is extract from CAD data base. Attributes of seventy different type of metal for work piece, eight different type of material for tools, and different type of dielectric, are stored in databases. The knowledge base is linked with CAD data base. The surface roughness and peak count and other necessary variable, are estimated. The system provides useful information for product designers and also advises manufacturing engineers to select optimum machining parameters. For validity of the expert system, out put of expert system compars with output of experimental. The results shows that estimating of machining time and cost, surface roughness and peak count of intelligent system 10 percent better than experimental. Keywords: expert system, Electro-discharge, texturing, Texture technology, laser , electron beam, ion beam

Sustainable growth of a company share value, regardless of financial flow and integration of financial decisions with other physical decisions, is not reachable. Value based supply chain management, attempts to make it possible through taking working capital and fixed assets into consideration as well as factors such as sales and costs. In this paper a mixed integer programming is presented to integrate financial and physical decisions in a multi echelon, multi period and multi commodity supply chain in order to maximize economic value added, as a most prevalent value metric. Working capital management with the option of pre-buy or pre-sell as well as the credit buy or credit sell is one of the most important contributions of this paper. Performance and validation of proposed model, are proven through solving large scale problem sizes. Then, the effect of different buy and sell options, are illustrated. Company value is 64% reduced when options were not considered.

In this paper, we address a variant of the Location-Routing Problem (LRP), namely the Two-echelon location routing problem with simultaneous pickup and delivery (2E-LRPSPD). The purpose of location-routing problem is to determine the optimal number and locations of depots while allocating customers to depots and determining number of optimal vehicle and vehicle routes to visit all customers. The objective is to minimize both the cost of open depots and the total cost of the routes. In this paper customer’s demand is uncertain with discrete values in fuzzy trapezoidal numbers. Applying this approach can result in making an appropriate decision of service level for customers by experts while accounting for considering the system’s costs. We propose an adaptive large neighborhood search for the Two-Echelon Location-Routing Problem with simultaneous pickup and delivery (2ELRPSPD). Computational experiments conducted on several sets of instances from the literature show that our algorithm outperforms existing solution methods for the 2E-LRP and a new data set is also generated for our presented model which contains both pickup and delivery demands and Computational results are reported. The results imply the efficiency of the proposed algorithm in finding better solution in comparison to the ones obtained via other algorithms existing in the literature of location routing problem.

In this paper, a mathematical model for balancing energy and power generation in a solar chimney power plant has been developed. Using this mathematical model, the amount of power produced by a solar chimney power plant, have been investigated. The governing equations written power plants, Then Equations, using simulated annealing algorithm and particle swarm optimization were solved. To validate the model, the data contained in the reference paper is used. The results of this study show, The thermal efficiency of the solar chimney power plant, a small number. Proportion Power produced to the total energy for the reference data, approximately 0.6 percent. Most heat transfer occurs between the ground and the roof of the plant. By changing the geometry of power plant, Power, significant changes. According to energy balance, heat input is more increased temperature surfaces, As a result, waste of energy. In this method, using optimization algorithms, Speed solution Increases. And by increasing the number of Iteration the algorithm, Accuracy of the results will improve.

One of the main reasons for lack of competitiveness in automotive production in our country is mismanagement in supply of primary parts and transporting them to the domestic auto companies. This paper presents an integrated approach in order to make decisions to schedule orders of production and transportation, including assigning orders to suppliers and vehicles, sequencing production orders for suppliers and the way they are transported to Iran Khodro company. A shared transportation navigation is also considered in the problem. In order to optimize decisions in the proposed model, a genetic algorithm is used. In comparison to integrated and non-integrated models and the developed genetic algorithms used recently in the literature, the algorithm suggested in this paper gives a better performance. Furthermore, when compared to a real case, the proposed algorithm in this paper showed superior results.

Atomic force microscopy is a powerful tool in imaging and detection of nanoscale materials. The performance of this device in liquid environment has a great advantage such as ability of imaging biological samples, reducing the van der Waals forces and elimination of capillary forces. Understanding of dynamic behavior of the device in liquid environment under various conditions is essential. Therefore in this paper the atomic force microscopy is modeled as a cantilever beam and its dynamic behavior is investigated using the analytical method of multiple scales. For this purpose the equation of motion of microcantilever is obtained using the continuous beam model. Subsequently the hydrodynamic force due of fluid incorporates into the equation using additional mass and damping. Then using the method of separation of variables and use of the Galerkin approximation method, partial differential equation of motion of the beam is turned to an ordinary differential equation. Finally, using the method of multiple scales, the frequency response of the micro-beam near its resonance frequencies is obtained. Moreover the effect of the fluid viscosity and beam dimensions on beam frequency response is studied. In addition, since in nonlinear systems, addition to the primary resonance, it is possible to there is another resonant frequencies, so in this paper the resonant frequencies other than the natural frequency of the linear system is studied and the existence of two resonant frequencies lower than the natural frequency is shown.

The goal of this paper is to minimize self-excited vibration in the micro-milling process. This goal is achieved by using passive linear and nonlinear vibration absorbers. By reducing this unwanted vibration the final surface will have better surface quality. In this paper the micro-milling process is modelled as a two degree of freedom system and the effect of the cutting tool eccentricity is considered. To have stability for the larger depth of cut the optimal parameters for the passive vibration absorber is defined by a developed algorithm. The effects of vibration absorber on the stability and time response are investigated. The results show that using an optimal vibration absorber the vibration amplitude decreased and stability zone enlarged sensibility.

In this paper, the problem of scheduling and sequencing of multi-objective two-stage flexible flow shop with dedicated assembly lines, which produce various products during multiple planning periods, is proposed. The objectives of the proposed model are minimizing maximum completion time of products and total average weighted tardiness of production products. The first stage of the proposed flexible flow shop involves of several different parallel machines in site I and one machine in site II, and the second stage involves of two specific dedicated assembly lines. Each product has a specific bill of materials as well as has its own specific configuration which leading to difference processing times to assemble. Products composed of only single-process components are assigned to the first assembly line and products composed of at least a two-process component are assigned to the second assembly line. Components are placed on the associated dedicated assembly line in the second phase after completion of production process on the assigned machines in the first phase and final products will be produced by assembling the components. Uncertainty of demand of final products is handled via robust optimization technique based on the concept of uncertainty budget. The main contribution of this paper is development of a new mathematical model in flexible flow shop scheduling problem with dedicated assembly lines under uncertainty and presentation of a novel hybrid meta-heuristic for solving the proposed model. Due to the NP-hard nature of the proposed multi-objective problem, a hybrid evolutionary metaheuristic based on the strange Pareto evolutionary algorithm II is developed that incorporates a customized adaptive large neighborhood search as its local search heuristic. Extensive computational results illustrate the efficiency of the proposed model and solution algorithm in dealing with robust multi-objective flexible flow shop problem.

Topology optimization methods enable designers to find the best structural layout for required structural performances. Most papers in this area have been concerned with the optimization of structures with linear material. However, there are several structures involving nonlinear material.Evolutionary structural optimization (ESO) is based on the simple concept of systematically removing inefficient material from the structure after each finite element analysis, so that the resulting design is gradually evolved to an optimum. This method has been successfully applied to optimum material distribution problems for continuum structures and has been extended to a wide range of structural optimization problems. This paper is concerned with optimization of elastic and elasto-plastic bodies, based on the von Misses stress criterion using two method.Several examples are presented to verify the proposed optimization methods. Results are compared for these two criteria and against elastic and elasto-plastic material and also with that of the adaptive method. It is concluded that for elastic and elasto-plastic bodies, the behavior of the both criteria is more or less the same and they can be used alternatively.

In this paper, the position tracking problem of a magnetic levitation system with the external disturbance and uncertainties is investigated. The dynamic of a magnetic levitation is governed by a SISO third-order nonlinear differential equation and only the position measurement is available for control. In this paper, the combination of the feedback linearization and Back-stepping techniques is used as a new control method for this system. Feedback linearization and back-stepping techniques are introduced as methods for linearization of a system with coordinate transformation and nonlinear designing, respectively. In other hand, nonlinear disturbance observer has a good ability to estimate disturbances and nonlinear dynamics, so it is combined with designed controller to increase performance of the controller, reducing the effects of disturbances and system uncertainties by estimating them. Simulation results show that the proposed method has a good ability in the position tracking and a good performance in elimination of the external disturbance and uncertainties.

This paper determines the location of bank branches under competitive conditions with different attractive conditions. Finding an optimum location of branches depends on many factors and these problems are known as NP-hard problems. Despite being approximate methods, meta-heuristic algorithms seem suitable tools for solving NP-hard problems. In this paper, Genetic Algorithm (GA), Simulated Annealing (SA) and Cuckoo Optimization Algorithm (COA) are applied for finding the best location of bank branches. From marketing point of view, the aim is to attract more customers while the number of attracted persons to a new branch should be acceptable. The new methods have capability to find the optimum location of new branches under competitive conditions. The location of a new branch should be as far away as possible from branches of the same bank. The other condition is that the total number of customers for the new branch should not be less than a specified number, while the new branch should not attract customers of old branches of the same bank more than a threshold. To fulfill this propose a part of the Tabriz city was selected for implementation. Finally, to evaluate quality and accuracy of the algorithms, several iterations with different seeds are performed. The results of statistical and final tests indicate that the accuracy and convergence speed of Cuckoo Optimization Algorithm are more than the Simulated Annealing and Genetic Algorithms in finding optimal location of bank branches under competitive conditions.

Modeling and simulation of the bridge response during vehicle moving on it is very important in optimum bridge design. There are many researches in this field which some of them deals with studying of the structure and bridge uncertainty effects on the bridge-vehicle dynamic response. Some researchers are dealing with vehicle uncertainty that is uncertainty in mass, sprung, damping, velocity, numbers, incoming time and other mechanical parameters of the vehicles. Other researchers are considering the bridge parameters uncertainty like as module of elasticity, bearing immobility and mass of the bridge. Also in most of the researches, analytical and Monte-Carlo simulations have been used for obtaining the dynamic response of the bridge with considering mentioned uncertainty. However there isnât any accurate and general statistical study on the bridge response with general uncertainty. In other words, the complete set of uncertainty of the vehicles or bridge has not been applied in modeling and also the exact statistical study of the dynamic response of the bridge has not been applied exactly. Therefore in this paper, after modeling of the bridge-vehicle system with coupled finite element beam and discrete vehicle model, most of the uncertainties of the vehicles have been produced with Gaussian probability distribution function and the statistical parameters of the response have been extracted by Monte-Carlo simulation. The selected model applied in this paper is a discrete model of vehicle with four degree of freedom mass sprung system. Also, the Euler-Bernoulli model was used for bridge and the coupled dynamic equation was extracted using finite element modeling of the beam with Hermitian interpolation function for suitably dividing the vehicle forces, applied on the beam elements nodes. In addition the different road surface using ISO standard was applied on the finite element beam model. One of the major contributions of this paper is considering the type of the vehicle crossing on the bridge as an additional uncertain parameter which is not mentioned in the previous literatures. In other words, three classes of the vehicle that is heavy, semi-heavy and light ones was applied in simulation as uncertain parameters. The mechanical characteristics of the vehicle were derived by CARSIM software and by Monte-Carlo simulation using uniform probability distribution function. Then mentioned parameters was produced and entered in New-Mark simulation steps. With studying on the deflection, velocity, acceleration of the bridge and also considering corresponding upper and lower limit band (confidence interval) and variance of the mentioned parameters, extended results of uncertainties effects have been obtained. It should be mentioned, in this paper an exact statistical test method was used for obtaining the statistical properties of the dynamic response. Also, in different road surface and conditions, the simulation was carried out such that four surfaces of the bridge and three type of the vehicle classes was simulated separately and finally one simulation was done in complete set of the uncertainty. Very detailed and complete results were studied and one of the important results of this paper is reporting the most effective uncertainties on the bridge response. As one of the results, it was found that with increasing the velocity of the vehicle, surface roughness and weight of the vehicle, the uncertainty of the response are increasing. As another important result is that the fundamental frequencies of the bridge is less sensitive to the uncertainties of the vehicles' parameters. Derived results of this paper can be applied in optimum designs of the bridges and also in designing the damage identification methods.

Query expansion as one of query adaptation approaches, improves retrieval effectiveness of information retrieval. Pseudo-relevance feedback (PRF) is a query expansion approach that supposes top-ranked documents are relevant to the query concept, and selects expansion terms from top-ranked documents. However, Existing of irrelevant document in top-ranked documents is possible. Many approaches have been proposed for selecting relevant documents and ignoring irrelevant ones, which use clustering or classification of documents. Important issue in query expansion approaches is using relevant documents for selecting expansion terms. In this paper, we propose clustering of pseudo-relevant documents based on query sensitive similarity, which is efficient for placing similar documents together. Query sensitive similarity obtained good results in document retrieval rather than term-based similarity, is the reason for using in this paper. Clusters are ranked based on inner similarity, and some top ranked ones are selected for query expansion. Then, we extract expansion terms from documents of selected clusters based on Term Frequency- Inverse document frequency (TF-IDF) scoring function. Conducted experiments over Medicine dataset (MED) shows that retrieval results for expanded queries with selected documents from clusters is better than basic retrieval (VSM) and Pseudo-relevance feedback. In addition, the effectiveness of retrieval is raised.

In this paper, a mathematical modeling of nested hierarchical p-center problem is presented. In this model there are two levels of hierarchies and the first one should be passed to achieve the second level . The second level facility can provide both services of the first and the second level. This model is a linear integer mathematical programming model. To provide an application of the model, some simulated cases are investigated and resolved, the results show that using this model reduces the initial construction cost while the main objective which is maximum servicing distance will not be changed basically.for the large size problem using of metaheuristic algorithms is necessary so in this paper an algorithm based on the Particle swarm intelligence is proposed to solve the problem. Numerical results confirm efficiency of the algorithm.

This article presents a new energy management strategy (EMS) for optimal power allocation in the battery/supercapacitor hybrid energy storage (HESS) in DC microgrid applications. The proposed system is composed of a semiactive structure where the supercapacitor is directly connected to DC bus. In this structure, since the main purpose of the HESS is to maintain the DC bus voltage at the desired value, controlling the supercapacitor becomes more important. While, in the semi-active structure, there is no control on the supercapacitor. In this paper, by considering the supercapacitor current as a cost function in the optimization problem, this challenge has been solved. Also, in the case of microgrid excess power mode, a new cost function has been considered to charge the battery with a constant current to reduce the charging time and improve its lifespan. Another objective is to increase battery life by responding the supercapacitor to the sudden power changes and drawing a smooth current from the battery. In order to online determination of the optimal global solution, this multi-objective problem has been converted into a single-objective problem by use of the weighted method and then solved using KKT conditions. Therefore, real-time implementation is the main advantage of the proposed method. Finally, using simulation, the performance of the proposed method is compared with an adaptive cutoff frequency filter-based method and fuzzy logic method, in three 24 seconds different scenarios, in terms of the DC bus voltage regulation, the battery peak current, and the battery state of charge (SoC).