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Abstract: The requirements of device under the multi-mission of monitoring, protecting, controlling and communicating is discussed in this paper to bring forward a design of dual CPU structure with ARM & DSP for microprocessor protection. Via the comparative analysis of several common algorithms, the algorithm of FFT, which can make the controlling of calculation accuracy easier and has a filter feature inherently, is selected to analyze the sampling data of protector and calculates relative electrical parameters. Relevant program is written for distance protection in 110kV transmissions, then debugging on software and hardware is made. The results show that the design of DSP & ARM based-microprocessor protection presented in this paper is feasible; such a device has simple and reliable circuit structure and is expandable in both software and hardware. [Copyright &y& Elsevier]

Abstract: In recent years, with the extensive application of power electronics technology, power electronic devices such as non-linear loads is used more and more in power systems, which is inevitable that related current and voltage waveforms have a greater degree of distortion, thus affecting the power quality. It created a greater impact on power system security and the economy. Therefore, Researching on harmonic voltage and current the impact of power quality has a strong practical significance. In order to achieve the analysis of power quality parameters, you need to combine harmonic analysis algorithms and power quality parameter calculation algorithms to achieve the intended purpose. This paper presents Newton''s algorithm for harmonic analysis, combined with power parameter calculation algorithm, achieved the power quality analysis purposes. [Copyright &y& Elsevier]

Abstract: According to the features of mine geographic network, the paper presents an algorithm of route searching for mine geographic network called tree growth. This algorithm can improve the searching efficiency for avoiding searching for the intersection part of the routes. If the node of the subsequent growing branch is the same as any element of the intersection namely node (or called meeting with a refusal), it will immediately change the direction. The tree growth algorithm can avoid the problem of searching combination explosion and is applicable to route searching for large-scale mine. [Copyright &y& Elsevier]

Abstract: To a good number of medium and small enterprises, it is a serious problem how to decline production cost and improve the response to the market by normative management and sharing the information. As an advanced management method and an IT tool, ERP can solve all these problems well. And how to combine ERP with other advanced management methods (such as SCM) and make ERP fit to the mid-small enterprises becomes a hot question recently. Purchase stands on the upstream of SC and takes a strategic effect on cost and quality control. Advanced and efficient purchase management not only can supply continuous material to keep enterprise run perfectly but also can make enterprise more competitive in controlling the whole SC. MRP algorithm designed in this paper can be a good application of procurement management in the ERP system, and achieved good economic. [Copyright &y& Elsevier]

Abstract: In this paper, a new algorithm is proposed for estimation of one-dimensional coherent signal direction of arrival (DOA) based on MUSIC algorithm. Compared to spatial smoothing algorithm, a situation that the sub-array number and the total array number are the same has been extracted. Its best advantage is that it won’t cause a reduction of the array aperture and no aperture loss. In most cases, the proposed DOA estimation scheme outperforms the traditional spatial smoothing algorithm. [Copyright &y& Elsevier]

Abstract: String matching is a fundamental problem in computer science. Multi-string matching plays an important role in pattern recognition, search engine, virus prevention, intrusion detection and others. Aho-Corasick (AC) algorithm is a widely used multi-string matching algorithm. In this paper, we present a space compacting method for AC automata based on node grouping and implement AC algorithm on GPU platform using CUDA (Computer Unified Device Architecture). We accelerate the anti-virus systems by our approach. We conduct several experiments, and our algorithm has at least 10 times of speedup of the algorithm on CPUs. [Copyright &y& Elsevier]

Abstract: The interior function int in computer algebraic system Maple always return unevaluated or an expression with transcendental functions for lots of definite integrals, whereas we could obtain the perfect result according to the method of mathematical analysis. In this paper, by using the theories of mathematical analysis and computer algebra, an effective algorithm for definite integral was established, and a new Maple program myint for it was established, too. It indicated that myint has the better ability for computing the definite integral than int in Maple of the current version. This would be useful for some calculating problems of engineering mathematics. [Copyright &y& Elsevier]

Abstract: Graph drawing problems can be applied to many reality places, which also deduce to some important graph drawing problems. Such as aesthetics criteria whose optimization can lead to acceptable drawings. This paper gives an algorithm for optimizing these criteria. We propose a new force-directed model to solve the graph drawing problems in 2-D frames and modify this hybrid force model to promote to normal drawing frame shape, especially regular triangle and circle drawing frames. For the regular triangle drawing frame, it can be applied to tree drawing problems and for the circle drawing frame shape we use it to suit the normal graph drawing problems. [Copyright &y& Elsevier]

Abstract: The newest international video coding standard H.264 is very efficient in solving the limited bandwidth problem and improving the quality of reconstructed image. Although H.264 has many potential application fields, the big computation complexity becomes a bottleneck for its real time applications. In this paper, we proposed a fast mode decision algorithm of 4x4 block intra prediction to optimize the H.264 encoder. Experimental results show that it can reduce the computational complexity of the H.264 encoder remarkably at the expense of little quality degradation. [Copyright &y& Elsevier]

Abstract: In this paper, a kind of nonlinear optimization problems with nonlinear equality and inequality constraints are discussed, and a new algorithm with arbitrary initial point is presented by combining the norm-relaxed method of feasible direction for inequality constrained optimization with the idea of strongly sub-feasible direction method and the two concepts of quasi-KKT point and quasi-multiplier method. Firstly, the original problem is transformed into an associated simpler problem with only inequality constraints and a parameter. The later problem is shown to be approximately equivalent to the original problem if the parameter is large enough (but finite). At each iteration of the proposed algorithm, a direction is obtained by solving one direction finding subproblem which always possesses a solution. Some good properties of the new algorithm are that the initial iteration point is arbitrary and the number of the constraint functions satisfying the inequality constraints is nondecreasing. The algorithm is proved to be globally and strongly convergent under mild conditions. Finally, the numerical experiments are implemented on Matlab7.0. [Copyright &y& Elsevier]

Abstract: The blind signal separation which has many potential usage, especially in the respects of such as wireless communication, medical analysis, geographical exploration, and image enhancement and recognition is a developing basic research direction. This paper mainly studies the application of it in speech processing and proposes a mathematical description of the blind signal separation problem in including mathematical model for blind separation problem and basic assumptions to ensure the blind separation to be solvable. It focuses on the analysis of the blind signal separation based on instantaneous mixed mode. It also proposes speech blind signal separation algorithm based on instantaneous mixed circumstance and performs computer emulation and signal-to –noise-ration analysis to confirm the effectiveness of the algorithm. [Copyright &y& Elsevier]