Applied Mechanics and Materials Vols. 713-715

Abstract: Hereby a normalized p-norm blind equalization algorithm with adaptive momentum was proposed. Normalized p-norm LMS-CMA can obtain robust convergence performance under impulsive noise environment, however, the convergence rate is slow. To further improve the performance of the normalized p-norm LMS-CMA, adaptive momentum according to the instantaneous error is designed. If the instantaneous error based on CMA criterion and DD criterion has the same sign, the momentum factor remains unchanged. Otherwise, the momentum factor is set to 0. The simulation results show that, the proposed algorithm has faster convergence rate than the normalized p-norm blind equalization algorithm, furthermore, it has robust convergence performance under impulsive noise environment.

Abstract: With the development of mobile communication, D2D (Device-to-Device technology) has become a research hotpot. In this paper, we first derive the channel capacity of an n-hop link and get the formula of spectrum efficiency. And then to maximize the spectrum efficiency, we focus the algorithm of selecting the best relay for data transmission in a D2D cluster of cellular network. The algorithm proposed in this paper is an improvement of the greedy algorithm. This algorithm solves the problem that the greedy algorithm would be invalid in the case of having a big hole in the topology. At last, we could see a significant gain in terms of spectrum efficiency by using the new relay selection algorithm.

Abstract: This study is focused on audio streaming synchronization problems of multimedia network. Audio streaming synchronization issues of multimedia network directly affect the development of multimedia technology. To this end, this paper presents a multimedia network audio stream synchronization method based on the whole node identification, with feature detection method to identify endpoint of audio streams in perception node, and an audio fingerprint is conducted for information of each node, then, mark the starting point of sync, and sync tasks are decomposed at each node, and finally the audio stream synchronization is achieved in the cluster head node, error correction adjustment and information correction are performed to reduce the energy consumption of cluster head node, enhance correction capability of information loss. The simulation results show that the synchronization delay of proposed algorithm is significantly reduced, which enhance the performance of the multimedia network.

Abstract: Routing algorithm based on ant colony optimization for wireless sensor networks has the ant colony algorithm characteristics of self-organization, the positive feedback and the parallelism, which has good performance in constructing the optimal routing. In this paper, the distance for stimulating factor is improved, the communication distance is introduced and the pheromone update methods having the rewards and punishment mechanism are adopted, which can make better use of residual energy for wireless sensor networks nodes, prolong life of network and guarantee the effect of the optimization algorithm.

Abstract: Price is the main competition means in China's mobile communications market, scientific pricing methods and strategies are important issues must be resolved by operators. Meanwhile, the pricing strategy selection of service product is an important decision factor in mobile communication business marketing. Based on this, this paper through analyzing on the cost-plus pricing strategy, competition-oriented pricing strategy and customer-oriented pricing strategy, consider mobile communication enterprise pricing strategy should be selected according to their own environment and the different stages of the mobile service growth, so that pricing is more in line with the subjective wishes of the client, and favorable for long-term interests of the enterprise.

Abstract: Because small value and rapid changes, bus load is severely affected by meteorological factors. The article focuses on the precipitation, the average pressure, the average wind speed, the average temperature and the average relative humidity, and identifies the meteorological mutations. In the case when there is no mutation, predict the load trends based on the Single Exponential Smoothing method, otherwise, if there exists meteorological mutation, use SVM model to predict the load, as well as in the event of extreme weather conditions, start the emergency warning plan. By the case study of the No.1 main transformer of certain area in Jiangsu Province, the result shows that this method has good prediction results.

Abstract: This paper studied the application of fuzzy comprehensive evaluation in meteorological mutation identification of load forecasting. It measured out a specific algorithm in meteorological mutation identification of ultra-short-term load forecasting, so that to improve the load forecasting accuracy and reduce the relative error. When using the fuzzy comprehensive evaluation method, set the membership function and factor right based on the characteristics of a province for the summer weather factors, and measure the mutation membership value with the appropriate operator, which can provide a reference for the study of meteorology identification. The result shows that using fuzzy comprehensive evaluation to identify meteorological mutation has good usability and accuracy.

Abstract: With SVG technology becoming more and more mature, chain SVG is also installed in some power grid substations to solve local power quality problems, and certain effect has been achieved. Compared with other compensators in the substations, for example, capacitor bank, SVQC, SVC etc, actual loss of SVG is above average level, this limits its practicability.This paper puts forward a method that utilizes soft switch technology to reduce IGBT on/off loss in SVG device, gives main circuit topology of the designed soft switch PWM inverter, and the comparative analysis with on/off loss of hard switch, proves effectiveness of this method.

Abstract: The amount of random variation of wind speed, wind turbine output power are volatile, a lot of wind power will be on the safe and stable operation of power systems and power quality pose serious challenges, so the wind farm wind speed and power generation forecast scheduling and management of wind farms play an important role. According wind with chaotic discuss the use of phase space CC method to reconstruct the chaotic time series, and the phase space of a wind farm 10 units were reconstructed using the weighted first order local prediction model to obtain short-term within 1h wind forecast values obtained using the power curve conversion method of generating power for each unit. By examples show that the proposed method is feasible and effective.

Abstract: The high-altitude missile and other special application occasions have requirements on image storage system, such as small size, high storage speed, low temperature resistance, etc. Commonly used image storage system in the market cannot meet such requirement. In the paper, real-time image storage system solutions on missile based on FPGA should be proposed. The system mainly consists of acquisition module and memory reading module. The whole system adopts FPGA as main control chip for mainly completing real-time decoding and acquisition on one path of PAL format video images, reading and writing of NandFlash chipset, erasure, bad block management and so on. The solution has passed various environmental tests with stable performance, large data storage capacity and easy expansion, which has been used in engineering practice.