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Aimming at the severe security threat faced by information transmission in wireless communication, the artificial interference in physical layer security technology was considered, and the influence of artificial interference signal style on system information transmission security was analyzed by simulation, which provided technical accumulation for the design of wireless security transmission system based on artificial interference.

It is an important topic in the current image processing and analysis to use the photos or video to determine the shooting position and time. Analyzing the change of the object's sun shadow is an effective way to solve this problem. In this paper, the 3D scene photography is modeled to simulate the virtual reality by the software UnrealEngine 4 and the scene of the video can be reproduced accurately. The values of the solar angle parameters in the virtual environment can be shown on the software interface directly, so the solar elevation angle and solar azimuth angle can be fitted with these data to simplify the unnecessary mathematical derivation and programming. Furthermore, a measurement that reflects the deviation of the theoretical values calculated by the formula and fitted values is set as Difference of Angle. Finally, with the minimum Difference of Angle as the optimization goal, the rough possible range of the optimal solution is determined by the discretization search and the optimum solution is calculated by the least squares method. The result shows that this model is generally-used and operable. This method based on virtual reality technology has high maneuverability and accuracy, with good scalability for the number of unknown parameters.

Language model (LM) plays a vital role in automatic speech recognition (ASR) systems. Since the performance of a LM is highly dependent on the lexicon, crafted lexicons are commonly used for ASR tasks. However, it is hard to construct high-quality Chinese lexicons because a great deal of time and manpower are required. In this paper, we proposed an improved lexicon generation method for mandarin speech recognition. And we applied our generated lexicon to word segmentation and ASR tasks. In word segmentation experiments, we evaluated our proposed method both on the MSR and PKU data which are provided by second Sighan bakeoff. Results show that our proposed method achieved higher F-scores than previous lexicon generation methods. When applying our generated lexicons to training LMs for ASR tasks, our proposed method further reduced character error rate (CER) on both telephone speech evaluation sets compared with previous methods.

Widget is an increasingly popular technology and can be designed to perform various tasks. Easy to develop, easy to deploy, personalized, interactive, and less consumption of flow of mobile widget make it ideal for mobile Internet. However, cross-platform development of mobile widget is still challenge, and one of the most difficult problems is implementation of cross-platform API. The purpose of this paper is to research APIs of several specific platforms and propose an effective method to achieve cross-platform widget development. The framework of Mobile Widget Portable Development Library is used while developing cross-platform widgets, which offers approaches to meeting the aforementioned challenge.

For a class of interconnected large-scale systems, a design of decentralized dynamic output feedback controller is given. Not only the controller possessing integrity with sensor or actuator failures is given respectively, but also the design of the controller with two failures (both actuator and sensor failures) is presented. The results can be obtained by solving a set of linear matrix inequalities. A simulation example shows the design procedure and its effectiveness.

The trusting and cooperative relation between government principal and Construction Agency (CA) which based on the reputation effect from repeated game of principal and agent is a long-term incentive mechanism in government investment project. The importance of reputation effect is increasing in the construction agency competition, and the selection of CA based on reputation need an effective measurement of the reputation for CA. The paper analyzed components and driving factors of CA reputation, establishing CA reputation measurement indexes system and model from the view of stakeholders. However the measurement indexes should need further empirical study. Only by this the reputation evaluations can be introduced into CA Market Access management in order to establish a kind of cooperative relation in CA market and make it more perfect.

This paper develops a methodology for the optimal design of reliable control system. For a class of large-scale systems, optimal reliable guaranteed cost stabilization with continual gain actuator faults is presented. Based on the lyapunov method and linear matrix inequality, a sufficient condition for the existence of decentralized dynamic output feedback reliable controller is given. The design guarantees the system asymptotic stability and minimizes the upper bound of a given quadratic cost function. Simulation results show the effectiveness of the design method.

This study focused on soil microbial activity and bacterial diversity exposed to long-term elevated CO2. Bacterial numbers, microbial biomass C, soil basal respiration, dehydrogenatase activity, and bacterial diversity were investigated in pinus koraiensis seedlings. The results indicated bacterial numbers decreased significantly (p ≤ 0.05) at elevated CO2 in July and August, but not of it in September. Microbial biomass C decreased significantly (p ≤ 0.001) at 700 μ mol/mol CO2 compared to screened ambient and ambient, but not of it under 500 μ mol/mol CO2. Soil basal respiration (p ≤ 0.05) and dehydrogenatase activity (p ≤ 0.001) increased significantly under elevated CO2 compared to ambient and screened ambient. Bacterial community structure changed evidently under elevated CO2 compared to ambient through DGGE (Denaturing Gradient Gel Electrophoresis) analysis of bacterial 16S rDNA gene fragments amplified by PCR from DNA extracted directly from soil. It was concluded that soil microbial activities and bacterial diversity were significantly influenced by elevated CO2 compared to ambient.

The principles of Support Vector Regression (SVR) are described. The collection and treatment of customer demand, the moving time window method, the selection of training samples and the analysis of forecasting accuracy are stated. The customer demand forecasting approach based on SVR using moving time window method is proposed. With the demand data of a simulation example, the presented approach is used to forecast the demand values for 7 days ahead. The average forecasting error is less than 2%. The simulation results demonstrate the approach is feasible and valid in customer demand forecasting.

Reusing Open Source Component (OSC) has become more and more popular in developing in-house applications. Before integrating an OSC into project, the component has to be evaluated according to the project. The lack of effective documentation, however, makes it hard to evaluate OSC. Behavior and performance are always the concentrated ones among the proposed criteria. But how to get access to the behavior (especially the runtime behavior) and performance for OSC is still less touched. This paper proposes the usage and dependency model to help understand OSC from the interactions with its context. The usage and dependency model extends the traditional usage model with the context dependency and backward dependency that are widely observed in open source project. Based on the usage model, this paper proposes three metrics to measure the complexity of the interactions. To help evaluate the performance, an unbiased performance model is proposed to measure by both the time and memory performance. The time performance in this paper can be measured according to usage and component state. To extract the usage and dependency model, the invocation matrix and the mining algorithm are proposed. The framework component in open source project Junit 4.4 is selected to validate this research. The case study reports the models and metrics on the component and provides direct evidence on how difficult to reuse it.

As the organic combination of information technology and government management function, E-government has created a kind of new management fashion and method. In this article, the resource integration idea of E-government including the idea of requirement management and the idea of information resource management are suggested. Then, the advanced management thoughts and methods such as ERP and CRM are introduced into the integration study on the government inner resource and outer service. The optimization implementation framework and its function of E-government are suggested from the inside network and outer network of government. We hope it can accelerate the construction and implement of E-government.

The dynamic of a large-scale power system can be represented by parameter dependent differential-algebraic equations (DAE) in the form of x= f(x-y-P) and ()= s[x,y,P) . When the parameter p of the system (such as load of the system) changes, the stable equilibrium points may lose their dynamic stability at local bifurcation points .Then the system will lose its stability at the feasibility boundary, which is caused by one of three different local bifurcations: the singularity induced bifurcation, saddle-node and Hopf bifurcation. In this paper, the dynamic voltage stability of power system will be introduced and analyzed. Perturb and Taylor's expansion (PTE) technique is used to describe the DAE by singularly perturbed ordinary differential equations (ODE), and equilibrium manifold is solved by continuation method. The analysis avoids the singularity induced infinity problem, which may happen at reduced Jacobian matrix analysis, and is more computationally attractive.

Accounting for the closed-loop control system of linear permanent magnet synchronous motor is apt to be disturbed. It is the main problem which can degrade the performance of the control system and even destabilize the system. Presenting an on-line identification method of model reference adaptive control based on fuzzy neural network on the paper. And the inputs and membership parameters of the fuzzy controller are modified in real-time by a gradient method. It is proved that the method above is valid for improving the resolving of velocity detects device and dynamic response by simulation and practice. And the system is robust.

This paper presents a novel single-chip IC (integrated circuit) realization of the 3-sinusoidal PWM (SPWM) controller. The controller's outputs, such as fundamental voltage, frequency, dead time and so on, are controlled by several input clocks' frequency. With an EDA (electronic design automation) methodology, the control IC is implemented using only one single advanced FPGA from Altera, Inc. The output fundamental frequency can be adjusted from 0.094 to 2 kHz or more, and it can be real-time display. The SPWM switching frequency can be set 50 kHz. The dead time for the IGBT is arbitrarily adjustable. The designed SPWM IC can be incorporated with a digital signal processor (DSP) to provide a simple and effective solution for high-performance AC drivers. Further more, the design can be converted into a soft IP (intellectual property) core for other purposes. Simulation and experimental results are given to verify the constructed controller.