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Abstract: A new design of decentralized load-frequency controller for interconnected power systems with ac-dc parallel using Particle Swarm Optimization (PSO) algorithm is proposed in this paper. A HVDC link is connected in parallel with an existing ac tie-line to stabilize the frequency oscillations of the ac system. Any optimum controller selected for load frequency control of interconnected power systems should not only stabilize the power system but also reduce the system frequency and tie line power oscillations and settling time of the output responses. In practice Load Frequency Control (LFC) systems use simple Proportional Integral (PI) or Integral (I) controller parameters are usually tuned based on classical or trial-and-error approaches, they are incapable of obtaining good dynamic performance for various load change scenarios in multi-area power system. For this reason, in this paper the PI and I control parameters are tuned based on PSO algorithm method for the LFC control in the two-area power system. A two area interconnected thermal power system is considered to demonstrate the validity of the proposed controller. The simulation results show that the proposed controller provides better dynamic responses with minimal frequency and tie-line power deviations, quick settling time and guarantees closed-loop stability margin. [Copyright &y& Elsevier]

Abstract: The algorithm based on context similarity has the drawback that it will cost more time if not all the attributes are detected, this paper views the context attributes as attribute stream and the BOAS (Bayesian on the Attributes Stream) algorithm based on context knowledge is proposed in this paper. BOAS algorithm firstly calculates the undetected attribute of terrorism group identifier, and then uses conditional probability and Bayesian theorem to predict the future terrorist behavior. In this way, it avoids handling the undetected attributes in the original algorithm, but also avoids computing the context similarity based on distance function repeatedly. Thus, it improves the performance efficiency. The experiment result shows that BOAS algorithm proposed in this paper reduces computation time while it assures the accuracy of the prediction. [Copyright &y& Elsevier]

Abstract: Large solar thermal systems (LSTS) are a promising market segment for solar energy. However, the realization of LSTS is more challenging compared to smaller plants, in both technical and economical terms. Permanent monitoring, data evaluation and fault detection during the operation of LSTS has shown by Fink et al. [3] and Peuser et al. [13] to be crucial for ensuring optimal performance. The only cost-effective way for permanent surveillance of LSTS operation is to make use of a computer-aided tool that performs as many steps as possible in an automated mode. The R&D project ‘IP-Solar’ developed the scientific basis and the technical fundamentals for such a system. This paper presents the current state of development emphasizing the methodology of the operation diagnostics. In particular, the algorithm-based approach, its implementation and testing are described in detail. [Copyright &y& Elsevier]

Abstract: This paper shows that we can improve the performance of the auto-adjustable electric machines if a fractional dynamic is considered in the algorithm of the controlling order. This structure is particularly interested in the separate control of active and reactive power of the double-fed induction generator (DFIG) of wind power conversion chain. Fractional regulators are used in the regulation of chain of powers. Knowing that, usually, the source of DFIG is provided by converters through controlled rectifiers, all this system makes the currents of lines strongly polluted that can have a harmful effect for the connected loads and sensitive equipment nearby. The solution to remedy these problems is to replace the power of the rotor DFIG by a matrix converter which represents a THD less important. The structure of the adopted adjustment is tested using Matlab/Simulink and the results are presented and analyzed for a variable wind. [Copyright &y& Elsevier]

Abstract: Considering the increasing role of microturbines in distributed generation of combined heat and power (CHP), the localization of microturbine design and manufacturing technology has received great importance in Iran. Providing a complete and comprehensive algorithm can be a major step in reaching the goal. In this paper, we present the cycle for the thermofluids design of a 100 KW microturbine which is carried out at the Niroo Research Institute of Iran to simultaneously generate both electricity and useful heat. The characteristics of this system are as follows: revolution speed of 47750rpm, single shaft, natural gas as fuel, single stage radial turbine/compressor and annular combustion chamber. Based on the thermodynamic characteristics of the cycle, the characteristics of different components of microturbine are determined throughout the study. According to the determined values, we expect the cycle to achieve an efficiency of approximately 13% without the recuperator and 25% with the recuperator. It must be noted that the designed microturbine is going through the final assembly stages at the time and the performance test has not been conducted yet. Therefore, the over-all characteristics curve of the system was not available at the time of preparing this article. [Copyright &y& Elsevier]

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

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

Abstract: FP-Growth is a recursive mining algorithm for frequent patterns. With each recursion, a new FP-tree and the corresponding header table are built. This paper proposes another approach to improve the mining efficiency: only one FP-tree is constructed, and instead of building new trees in every recursion, builds new header tables; frequent patterns are generated along the way, so we call this algorithm “header table recursion (HTR)” method. Tests show that it will get better performance for relative small datasets because the compress of the FP-tree has no significant impact on the performance yet inflicts extra time cost in tree creation operations. However on larger datasets, the traversal of the original FP-tree will become more time-consuming and its overall performance needs further testing. [Copyright &y& Elsevier]

Abstract: Real-time rendering of complex terrain, which is often used to meet the demand of the high fidelity of the virtual battlefield environments simulation, geographic information system (GIS), virtual reality (VR) and 3D games, has attracted growing interest at home and abroad over the last decades. In this paper, a hybrid terrain rendering algorithm combining multi-resolution terrain rendering and occlusion culling is analyzed, a terrain simulation loop which integrates multi-resolution terrain modeling and terrain occlusion culling based on the least square plane is proposed. The algorithm based on this method not only decreases the number of polygons sending to the graphics rendering pipeline efficiently, but also takes into account of the performance optimization and its extension for dynamic terrain. By implementing the algorithm and analyzing the results from experiments, we conclude that this algorithm is valid and applicable to complex occlusion-intensive terrain rendering system. [Copyright &y& Elsevier]

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

Abstract: In this paper we present a video segmentation method based on edge detection for separating moving objects from the background in video sequences, and the sequences were taken by stationary cameras. Firstly, the edge of target objects was divided into two parts, one is produced in each frame due to objects moving, represented as Edgem(x,y);the other is original-exist edge in the following frames, represented as Edges(x,y);secondly, Edgem(x,y) is made based on combining the change detection masks with the spatial segmentation in the current frame; thirdly, Edges(x,y) is performed based on combining the background subtraction result with the spatial segmentation in the current frame; then, merge the above –mentioned two fusion results; finally, through morphological operation to fill the whole target. Experimental results demonstrate the performance of our algorithm. [Copyright &y& Elsevier]

Abstract: Since the estimation of distribution algorithm(EDA) was introduced, different approaches for continuous problems solving have been developed. Through the efforts of many scholars, the EDAs brought some success in continuous domain, but there are still some deficiencies: Gaussian-based EDA doesn’t perform well in problems with many optima, such as Schwefel function; histogram-based EDA doesn’t perform well in problems with singular global optimum, such as Three-Peak function. Because of this, based on improved histogram-based EDA and referred to the idea of k-Means clustering, we built cooperative EDA. Experimental results showed that the improved algorithm in this paper can give comparable with or better performance than those improved algorithms. [Copyright &y& Elsevier]

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

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

Abstract: An improved spectral clustering approach based on differential evolution algorithm (DESC) is proposed in this paper. In our algorithm, we replace k-means with differential evolution (DE) as the final step in spectral clustering, thus it overcomes the deficiencies in sensitivity to initialization and local optima. Experimental results over artificial dataset and UCI dataset demonstrate DESC''s superiority in difficult clustering, steady performance and better accuracy. [Copyright &y& Elsevier]

Abstract: Small Unmanned aerial vehicles commonly use PWM signals for servo control. In order to verify the flight controller design, it is necessary to measure the PWM control signals. There are two difficulties: real-time and high precision. The PWM signal must be measured per 20ms punctually and the pulse width must be accurate to 0.001ms. In this paper, a new pulse width measuring method based on VxWorks and PCI8554 timer card is introduced, including the structure of measurement system, measurement algorithm and VxWorks driver developing techniques of PCI device. By testing, this measurement system''s real-time and accuracy performance satisfied UAV test facilities’ requirements. [Copyright &y& Elsevier]

Abstract: Recent research shows that CoSaMP with partially known support has better performance than traditional CoSaMP. However, there is lack of theoretical analysis for this algorithm. In this paper, we propose a new algorithm which combines CoSaMP with Shannon sampling and obtain the theoretical guarantee. The proposed method measures partially known support part of a sparse signal with Shannon sampling and measures the rest part with compressive sensing. Comparisons with previous related works are shown. [Copyright &y& Elsevier]

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