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The rapid development of renewable energy power has improved global energy and environmental problems. However, with the high volatility of renewable energy, it is an important challenge to guarantee the consumption of renewable energy and the reliable operation of high percentage renewable energy power systems. To solve this problem, this paper proposes a tracking absorption strategy for renewable energy based on the interaction between the supply side and the demand side, which adjusts the charging process of electric vehicles (EVs) through electric vehicle aggregator (EVA) to realize the tracking absorption of renewable energy abandoned electricity. In view of this process, we analyze the interaction among power grid, EVA and renewable energy generation (REG) as well as their market characteristics. The master-slave game model of EVA and REG was constructed considering the charging behavior characteristics of EVs and the output characteristics of REGs. Then the model solving strategy based on soft actor-critic (SAC) algorithm is proposed, and the REG pricing strategy and EVA scheduling strategy are calculated to optimize the mutual benefits. The case analysis shows that, under the same scale of electric vehicles, the proposed method can promote about 93.89% of the power abandonment consumption of wind power system, 96.00% of the photovoltaic system, and 97.41% of the wind-solar system. This strategy reduces the electricity purchase cost of EVA, promotes the interaction among renewable energy, vehicles and power grid, and improves the utilization efficiency of renewable energy.

When planning the trajectory of a mobile robot, it is usually necessary to use sensors to collect a large amount of position information. Because traditional computing methods cannot effectively use huge data sources, an edge computing that implements edge intelligent services on the side of network edge near the data source is proposed, which speeds up the process of data processing. However, the data collected through sensors may contain gross errors. In general, the influence of gross errors on state estimation are rarely considered when using particle filter algorithms for state estimation. In fact, the measurements of dynamic systems are often affected by different types of gross errors in the actual application process. Therefore, it is a problem worth studying that how to detect and compensate for different types of gross errors. In this paper, an improved particle filter algorithm is proposed for the position estimation of mobile robot dynamic system. Firstly, the gross error identification method is used to identify the types of gross errors, and then the various gross errors are compensated. Finally, the particle filter algorithm based on the measurements compensation is obtained. Simulation experiments on the position estimation of mobile robots are carried out to verify the effectiveness of the proposed method in solving the measurements with gross errors. The precise position estimation of the mobile robot is achieved. Through the simulation experiments on the position estimation problem of mobile robots, it is verified that the proposed method is effective in solving the measurements with gross errors. And the accurate position estimation of the mobile robot is realized.

6G was the current research hotspot. Through the analysis of UM-MIMO system model, frequency interleaving and antenna mapping, physical layer and link layer, combined with UM-MIMO channel matrix model, through the simulation ofUM-MIMO system based on array of subarray, the corresponding relationship between system capacity and signal-to-noise ratio was obtained, namely, improving signal-to-noise ratio can effectively improve system capacity, so as to guide network site planning.

Motivated by the application of high-density data storage technologies, symbol-pair read channels are proposed in which every two consecutive symbols are read together. A lot of work has been done on this coding model. Bounds of codes play an important role in coding theory, which act as criterions to measure the optimality of a code. Several bounds have been developed for symbol-pair codes, among of which the Singleton type bound is most popular one. In this paper, we continue the research of bounds and establish the Elias type upper bound for binary symbol-pair codes.

With the rapid development and application of novel network information technologies, the various radar and/or communication transmitters have become more intelligent and networked in modern electromagnetic operational environment, which causes the threat sensing architecture of traditional electronic warfare system more inadequate, especially encountering unknown threat signals or networked targets. In this case, the threat sensing becomes one of the biggest challenges that the traditional electronic warfare system is facing. Therefore, this paper proposed a novel heterogeneous architecture for cognitive sensor networks to facilitate efficient threat sensing. To deal with the heterogeneous problem of cognitive sensor networks, multiple constraints satisfaction based approach has been employed. And the game based resources scheduling scheme has been utilized to facilitate the efficiency. To the best of our knowledge, our work is the first one that introduces the heterogeneous cognitive architecture into threat sensing domain of electronic warfare system. The simulation results show the proposed novel threat sensing architecture for heterogeneous cognitive sensor networks is feasible and effective.

The model of the long period fiber grating (LPFG) inscribed in the eccentric core fiber (ECF) is proposed and analyzed theoretically. The variation of the transmission spectrum is calculated under different eccentricities on the basis of the coupled-mode theory. The calculation results indicate that the order of the cladding mode that has the largest coupling efficient with the core mode changes with the change of the core eccentricity, which results in the shift of the resonant peaks. In addition, the effective refractive index of the fundamental mode increases with the core eccentricity within a certain range. The model we have proposed can provide a valid reference for designing ECF and writing LPFG in the ECF.

This paper considers the problem of the attitude control for flexible spacecraft with disturbances, actuator fault and time delay. The disturbances include the bounded environmental disturbances and the disturbance caused by the vibration of the flexible appendages. A composite control structure, which includes unknown input observer control (UIO) and delay dependent H ∞ control, is proposed to achieve a stable control of the attitude angle and attitude angular velocity, and a decomposition coefficient of delay integral inequality is introduced to reduce the design algorithm conservatism. Finally, simulation results are given to show the effectiveness of the proposed method.

According to annual list of the top 250/225 international contractors published by Engineering News-Record(ENR) from 2007 to 2016, the paper filters thousands of data related to power engineering contract. On this basis, the business scale, growth rate and changing trend of international power engineering contract market are first analyzed. Then, with the introduction of a series of indicators, such as Market Concentration Ratio(CR), Herfindahl-Hirschman Index(HHI) and the proportion of international share, the paper studies the development status of large international power engineering contractors. Furthermore, the paper summarizes the performance of Chinese international power engineering contractors and points out the deficiencies. Altogether, through comprehensive service feature analysis of international power engineering contract market, the paper would like to provide decision information support for Chinese contractors to develop overseas power engineering contract markets. It's expected that the results would help power engineering contractors to better serve the market.

This paper presents a phenomenon of inrush current in three-phase transformer closing switch without load, a simulation model of three-phase transformer no-load switching inrush current was built by using the SimPowerSystems software package of simulink in Matlab software, and the simulation result was analyzed by Fourier transform analysis, which directly showing the characteristics of the three-phase transformer inrush current waveform.

This paper deals with the problem of attitude tracking control for MEVs (Mars entry vehicles). The rotational motion of MEVs system consists of fast subsystem and slow subsystem. The attitude dynamics are given by slow subsystem and angular velocity dynamics are given by fast subsystem. A T-S fuzzy modal is achieved to approximate the fast subsystem. Based on this obtained model, the attitude tracking control is designed via combining DOBC (disturbance-observer-based control) with delay-dependent H ∞ , control. Therefore, the delay-dependent state controller is obtained, which can reduce the effects of delay and disturbance on attitude. Finally, the effectiveness of our method is verified by numerical simulations.

The rapid development of positioning techniques has enabled information to be widely collected on continuously moving objects, such as vehicles and mobile device users. Database systems supporting massive updates and predictive spatio-temporal queries on the moving objects are essential for modern location-based services. On the other hand, information (e.g. Location and velocity) that describes the motion of millions of moving objects can be accommodated in main memory with modern computing machines. Thus, in-memory indexing techniques are gaining popularity among moving object databases. Recent works indicate that a simple uniform grid is one of the best choices for indexing moving objects in main memory. However, to the best of our knowledge, relevant works in the literature consider only grids in the location space but disregard the velocity information of the moving objects, which we believe can be exploited to further improve query performance. In this paper, we propose D-Grid, an in-memory dual space grid index for moving objects. Specifically, it indexes moving objects using grid structures in both location and velocity spaces, which improves query performance by almost an order of magnitude. We also propose a lazy deletion and garbage cleaning mechanism that can be applied to both our dual space and existing location space uniform grid based indexes and further improve update performance. Extensive experiments demonstrate that our approach significantly outperforms existing uniform grid based in-memory indexes.

Interference alignment (IA) is a promising technique to effectively mitigate interference in wireless communication systems. In this paper, a novel IA based scheme is proposed, which is jointed design of transmit precoding matrices and receive beam forming matrices for the three-cell multiple-input multiple-output (MIMO). Gaussian interfering broadcast channels (MIMO-IFBC) with constant channel between each node, where each base station (BS) is equipped with M antennas, each mobile station (MS) is equipped with N antennas on the cell boundary, and each BS sends d data streams to each user in its cell. This corresponds to a down link scenario for cellular networks, where K users with the user cooperation in each cell. It is also analytically shown that total 3Kd degrees of freedom (Do F) is achievable if M = N ≥ 2Kd. The simulations demonstrate the sum-rate of our proposed scheme also out performs those of conventional techniques, especially in the high signal-to-noise ratio (SNR) regime.

Plasma process induced damage (PID) to thin gate oxide of different thickness was investigated in this paper with antenna test structures to enhance the effect of plasma charging. Gate leakage under Fowler-Nordheim (F-N) stress, threshold voltage, and time dependent dielectric breakdown (TDDB) was applied for gate oxide degrading measurement. It is found that gate oxide with around 5nm electrical oxide thickness (EOT) is more sensitive to plasma process and can be easily revealed with gate leakage. Gate oxide TDDB test with short loop wafers indicated that contact (CT) etching stop layer and back end of line (BEOL) process, especially high density plasma (HDP) chemical vapor deposition (CVD) of inter-metal-dielectric (IMD) plays the main role in oxide damage. These phenomena provide important approaches to reduce PID effect in integrated circuit manufacturing.

Time Dependent Dielectric Breakdown (TDDB) is one of the major indices to evaluate the Gate Oxide Integrity (GOI) reliability of Integrated Circuit (IC) devices. Permutation and combination theory helps to derive the many combinations of temperature and voltage stress levels to determine TDDB parameters (i.e., γ and Ea) with a pre-specified sample size. In this work, a statistical tool (JMP10) with optimal experimental design platform for accelerated life test (ALT) is employed to select stressing conditions, to optimize the ALT test plan with a special distribution of sample size for each stressing condition, to model parameter estimation, and to predict lifetimes. Comparing our proposed DOE method to the most popular conventional method, we find our DOE method is better from both theoretical and experimental standpoints. Based on this study, we propose an optimized combination of stressing conditions and sample size allocation for each stress condition. Our proposed method saves capacity, shortens half of the test time, and obtains a narrower confidence interval (CI) of the estimated TDDB lifetime.

The interesting, targeted, relevant advertisement is considered as one of the most honest proceeds for personalizing recommendation. Topic identification is the most important technique for the unstructured web pages. Conventional content classification approaches based on bag of words are difficult to process massive web pages. In this paper, Wikipedia Category Network (WCN) nodes are used to identify a web page topic and estimate user's interest profile. Wikipedia is the largest contents knowledge database and updated dynamically. A basic interest data set is marked for WCN. The topic characterization for each WCN node is generated with the depth and breadth of the interest data set. To reduce the deviation of the breadth, a family generation algorithm is proposed to estimate the generation weight in WCN. Finally, an interest decay model based on URL number is proposed to represent user's interest profile in time period. Experimental results illustrated that the performance of Web page topic identification is significant using WCN with family model, and the profile identification model has a dynamical performance for active users.

Wireless communication network has such features as limited bandwidth, changeful channel and dynamic topology, etc. Ad hoc network has lots of difficulties in accessing control, bandwidth distribution, resource assign and congestion control. Therefore, a wireless resource distributing algorithm based on communication transmission performance factors is proposed in the paper. The algorithm makes quantitative and qualitative analysis for influencing factors of transmission performance, as a result, node resource distribution """"relative unfairness"""" is introduced to realize resource re-distribution while network resource is changing. At the same time, in order to ensure fairness of data transmission and timeliness of network packets, transmitting priority levels for each data packets are established based on latency time and its original priority level in the node. The simulation results show that the algorithm can ensure fairness and timeliness of network transmission, as well as improve ad hoc network resource integrated utilization efficiency.

The genetic algorithm of intelligent optimization algorithm is important in the distribution system reconfiguration. Aiming at genetic algorithm, exact penalty function based fitness function is proposed in this paper. Introducing avoid cycle method decode chromosome produced by Grefenstette code and generate dendritic-shaped distribution network. The decoding process is as following: First, forming branch sets, one of sets is composed by the order of network branches, the other sets is composed by the order of cycle network branches. According to the rules that distribution network can't be isolated operation and loop-net operation, at last generate dendritic-shaped distribution network. On this basis carrying on genetic evolution and then finding the minimum value of distribution network active loss. In order to evaluate algorithm performance, this paper propose optimization rate evaluation index which the probability of genetic algorithm find the global optimal solution. Three typical IEEE distribution systems are analyzed, and then we can obtain that the algorithm optimization ability has significantly improved, it is validity for different system.

Fault localization is one of the most expensive activities of program debugging, which is why the recent years have witnessed the development of many different fault localization techniques. This paper proposes a grouping-based strategy that can be applied to various techniques in order to boost their fault localization effectiveness. The applicability of the strategy is assessed over – Tarantula and a radial basis function neural network-based technique; across three different sets of programs (the Siemens suite, grep and gzip). Results are suggestive that the grouping-based strategy is capable of significantly improving the fault localization effectiveness and is not limited to any particular fault localization technique. The proposed strategy does not require any additional information than what was already collected as input to the fault localization technique, and does not require the technique to be modified in any way.

In order to accomplish IC design online and project management, an enhanced unified Electronic Design Automation (EDA) platform based on the WEB (abbreviated as WEB-EDA) is developed. The platform provides the sharing of cross-domain EDA resources via Shell mode and Desktop mode, IC design and project management. And for the purpose of safeguarding the online design environment, we adopt masquerade intrusion detection module and Role-Based Access Control (RBAC) module. WEB-EDA has been used in our laboratory. The experiences with the applications show that the WEB-EDA platform is highly effective and convenient.

A new method called EPDG-GA which utilizes the Edge Partitions Dominator Graph (EPDG) and Genetic Algorithm (GA) for branch coverage testing is presented in this paper. First, a set of Critical Branches (CBs) are obtained by analyzing the EPDG of the tested program, while covering all the CBs implies covering all the branches of the Control Flow Graph (CFG). Then, the fitness functions are instrumented in the right position by analyzing the Pre-Dominator Tree (PreDT), and two metrics are developed to prioritize the CBs. Coverage-Table is established to record the CBs information and keeps track of whether a branch is executed or not. GA is used to generate test data to cover CBs so as to cover all the branches. The comparison results show that this approach is more efficient than random testing approach.

In this paper, an improved method of Super Block Method (SBM) is presented for software testing. The primary idea of the method, called virtual node method (VNM), is to add virtual nodes to the control flow before the SBM is used. The same with the SBM, the VNM can help testers use minimal test cases to cover 100% blocks or achieve a desired coverage. Moreover, it can be used to reduce the overhead of program instrumentation for coverage testing by reducing the redundancies in the SBM. Essentially, the total overhead of program instrumentation is reduced not only by inserting fewer probes, which is realized by the SBM, but also by inserting the probes among the codes that are less likely to be executed. The experimental results show that the overhead of program instrumentation is further reduced by the VNM compared with the SBM.

In real-time embedded systems, due to race conditions, synchronization order between events may be different from one execution to another. This behavior is permissible as in concurrent systems, but should be fully analyzed to ensure the correctness of the system. In this paper, a new intelligent method is presented to analyze event synchronization sequence in embedded systems. Our goal is to identify the feasible sequence, and to determine timing parameters that lead to these sequences. Our approach adopts timed event automata (TEA) to model the targeted embedded system and use a race condition graph (RCG) to specify event synchronization sequence (SYN-Spec). A genetic algorithm working with simulation is used to analyze the timing parameters in the target model and to verify whether a defined SYN-Spec is satisfied or not. A case study shows that the method proposed is able to find potential execution sequences according to the event synchronization orders.

Statistical analysis is performed of observed concentrations of black carbon aerosol (BC for short hereafter), PM10, PM2.5 and PM1 (collectively called atmospheric particles hereinafter, when possible) made in 2006 over the Lhasa area of China, leading to some aspects of their variations in, and inherent correlativity between, atmospheric particles and BC there. Results suggest that the monthly mean mass concentration of BC and the atmospheric particles display a single valley form, with the biggest concentration in winter; the relative annual ranges show BC (PM10) to be smallest (largest); moist scavenging plays an important role in the variation of BC and the atmospheric particles; BC and these particles exhibit a bi-peak and bi-valley distribution for their daily change in mass concentration, with the peaks emerging in the morning and late in the evening. The correlativity analysis indicates that the BC and the atmospheric particles of the Lhasa region have the same emitting sources, with BC being the smaller-size particles.

A new method of retrieving aerosol optical depth (AOD) was proposed using daily global and diffuse radiative insolations. After a comparison with daily AOD products of AERONET, it shows that the correlation coefficient between the two AODs exceeded 0.95, and the mean bias error was less than 0.03. Using this retrieval method, AODs at 0.55mum were obtained at 14 meteorological observatories over China during 1961-2005. The analysis shows that, as to the average AOD for all the 14 stations of the 45 years, the mean value is 0.40 and its annual increment is 0.005. As to the seasonal average values, the AODs from high to low occur in order of spring (0.45), summer (0.43), winter (0.37) and autumn (0.34), separately. Over the 14 observatories, the stations of Chengdu in Sichuan Basin has the fastest AOD increasing speed of 0.01 per year, while AODs at Kashi and Geermu station show a slightly downward trend.

Data sending model in cluster has great impact on life of wireless sensor networks. In this paper, the data sending models were researched and a novel CIBT (Confidence Interval Banding Taboo-level) of data aggregation in cluster was formally described, designed, implemented and evaluated. The algorithm includes two stages. In first stage, the sampling data is used to set confidence interval to compare with total model. In second stage, taboo algorithm is adopted to avoid tandem duplication sampling. The performance of CIBT algorithm is evaluated from different aspects. Simulation results show that CIBT can better handle the energy efficiently and satisfy the desired accuracy given by different users. Comparing with similar methods, CIBT can better prolong network life.

The clonal selection (CS) algorithm is an optimization algorithm based upon the clonal selection principle in the biological immune system. This paper presents a novel approach that uses CS algorithm for path-oriented test data generation. The approach takes a selected path as a target and executes sequences of operators iteratively for test case to generate. An affinity function which is made up of a similarity and penalty value is developed to guide the test generator to make successive modifications of the test data, so that test data can ever closer to satisfy the requirement. The comparison results show that this approach is more efficient than those based on other heuristic algorithms in finding solutions.

We propose a video streaming system that uses many ordinary computers (peers) as servers, which is less costly and more scalable than using a single or a few dedicated servers. To circumvent frequent peer disconnects and limited peer up-link bandwidth, each video is coded into multiple descriptions, which are distributed over multiple peers. The system serves a client request by streaming multiple descriptions of the requested video from separate peers. Using the MD-FEC coding scheme, and simple models for peer disconnects, reconnects and for searching replacement serving peers after a peer disconnect, we simulated video streaming in such a system. Our results show significant benefits in using a large number of descriptions and serving peers.

A stationary frame-based synchronous digital current control for a surface mounted permanent magnet synchronous motor (PMSM) drive of integrated servo actuators is considered. A two phase stator stationary coordinate frame realization synchronous current controller with the anti-windup is presented. A simple implementation of space vector PWM algorithms which provide continuous transition from sinusoidal PWM to six-step operation PWM mode is developed to enhance the current dynamic performance

Robust streaming of video over the IEEE 802.11 wireless LANs (WLANs) poses many challenges, including coping with bandwidth variations and data losses. To address these challenges, we evaluate and compare various error control strategies in this paper, namely, medium access control (MAC) layer forward error correction (FEC), MAC retransmission, and application-layer FEC, combined with FGS scalable video coding to achieve reliable communication over the IEEE 802.11 WLANs. Moreover, we assess the performance of fine-grained loss protection (FGLP) for different multipath channel conditions. Furthermore, the performance of cross-layer strategies such as application-layer FEC with MAC retransmissions is also determined.