社保网络信息安全防护

本文针对各种威胁社保网络安全的多种因素,进行有的放矢地构建相应策略,综合立体地进行网络安全防护,构建了一个多方面考虑的安全网络,这样社保部门在保护计算机网络设备安全和计算机网络系统安全的同时也保护了数据的安全,为构建和谐社会贡献力量。     

Quarter Load Threshold (QLT) flow control for wormhole switching in mesh-based Network-on-Chip

The fact that latency increases abruptly once the on-chip network is saturated indicates that it is necessary to devise an effective flow control strategy. Through tracing the status of the network buffer space we found that the payload of the on-chip network cannot get beyond an upper bound to avoid vicious congestion. Specifically, quarter of the total network buffer space is such a threshold, which is termed Quarter Load Threshold (QLT). Based on this fact we present the Quarter Load Threshold (QLT) flow control strategy. The performance of the proposed strategy is evaluated by the open source simulator Noxim [Noxim: Network-on-Chip Simulator, http://sourceforge.net/projects/noxim, 2008]. Simulation results show that the on-chip network runs smoothly and no serious congestion is encountered any more.     

Robust Calibration for Localization in Clustered Wireless Sensor Networks

This paper presents a robust calibration procedure for clustered wireless sensor networks. Accurate calibration of between-node distances is one crucial step in localizing sensor nodes in an ad-hoc sensor network. The calibration problem is formulated as a parameter estimation problem using a linear calibration model. For reducing or eliminating the unwanted influence of measurement corruptions or outliers on parameter estimation, which may be caused by sensor or communication failures, a robust regression estimator such as the least-trimmed squares (LTS) estimator is a natural choice. Despite the availability of the FAST-LTS routine in several statistical packages (e.g., R, S-PLUS, SAS), applying it to the sensor network calibration is not a simple task. To use the FAST-LTS, one needs to input a trimming parameter, which is a function of the sensor redundancy in a network. Computing the redundancy degree and subsequently solving the LTS estimation both turn out to be computationally demanding. Our research aims at utilizing some cluster structure in a network configuration in order to do robust estimation more efficiently. We present two algorithms that compute the exact value and a lower bound of the redundancy degree, respectively, and an algorithm that computes the LTS estimation. Two examples are presented to illustrate how the proposed methods help alleviate the computational demands associated with robust estimation and thus facilitate robust calibration in a sensor network.     

Skew detection in document images based on rectangular active contour

The digitalization processes of documents produce frequently images with small rotation angles. The skew angles in document images degrade the performance of optical character recognition (OCR) tools. Therefore, skew detection of document images plays an important role in automatic document analysis systems. In this paper, we propose a Rectangular Active Contour Model (RAC Model) for content region detection and skew angle calculation by imposing a rectangular shape constraint on the zero-level set in Chan–Vese Model (C-V Model) according to the rectangular feature of content regions in document images. Our algorithm differs from other skew detection methods in that it does not rely on local image features. Instead, it uses global image features and shape constraint to obtain a strong robustness in detecting skew angles of document images. We experimented on different types of document images. Comparing the results with other skew detection algorithms, our algorithm is more accurate in detecting the skews of the complex document images with different fonts, tables, illustrations, and layouts. We do not need to pre-process the original image, even if it is noisy, and at the same time the rectangular content region of a document image is also detected.     

Correlation of direct piezoelectric effect on EAPap under ambient factors

Direct piezoelectricity of electro-active papers(EAPap)is analysed in this paper. The test setups for direct effect are designed and determined. Different ambient factors impacting the piezoelectricity of EAPap, such as temperature, humidity, and strain rate, are applied and analyzed. Strong piezoelectricity of EAPap is found on the basis of the test results and in comparison with polyvinylidene fluoride(PVDF)and lead zirconate titanate(PZT)-5H. The maximum piezoelectric constant is achieved to be 504 pC/N. The reason of strong piezoelectricity of EAPap is discussed in this paper. The potential of EAPap as a biomimetic actuator and sensor is also investigated.     

A collaborative platform for complex product design with an extended HLA integration architecture

How to integrate the heterogeneous, autonomous models in a distributed environment, running on Internet, integration based on multilayer federation architecture and simulation resources dynamic reuse are the major difficulties for complex product collaborative design and simulation. An extended HLA-based collaborative simulation platform for multidisciplinary collaborative design is proposed. The architecture of platform is first given. The idea and realization of four key technologies, the dynamic creation of simulation federation based on resource management federation (RMF), HLA enabled template, collaborative simulation algorithm based on stage-data synchronization and TH_RTI, an extensible HLA runtime infrastructure (RTI), which is a web enabled RTI and can be used at Internet, are emphasized. Finally, an industry case is given. The demonstration of these prototype systems shows that extended HLA integration architecture is effective infrastructure for multidisciplinary collaborative modeling and simulation (M&S).     

一种双环智能太阳能监控系统的设计与实现

针对目前平板式太阳能集中供热系统在农村应用较少的现状,采用智能控制技术开发了一种新型的太阳能控制系统;系统提出双环的控制结构,主环采用VC++操作串口实现数据的操纵与处理,副环的设计采用基于GSM和J2ME的无线多通道的实时数据采集与处理控制;对与建筑集成的太阳能供热系统进行控制,连续测试系统的运行状况;应用结果表明,该控制系统运行稳定可靠,满足了实时信号的处理要求;最后通过多项工程经济技术评价指标评价太阳能供热系统,事实证明具有一定的实用性和推广价值.     

卫星天线自动对星控制系统研究与设计

卫星天线手动对星方式存在精度不高、速度慢、操作复杂等缺点,针对这一现状,文章提出了一种二维卫星天线自动对星控制系统方案;系统以ATMega1280为控制核心,通过GSP、电子罗盘和绝对式编码器获取天线姿态信息,从而控制伺服电机来调整天线姿态,达到对星的目的;另外还实现了多组卫星数据存储、手动调节、误差补偿和参数实时显示等功能;实验表明,该系统工作稳定、精度高、响应速度快、操作方便,在军事和民用卫星通讯中均有较高的实用价值.     

基于FPGA软件/硬件协同设计模式

可重构的计算机系统利用现场可编程门整列（FPGA）加快那些在CPU中运行过于缓慢计算的速度。在CPU中运行的软件用来重构FPGA芯片让芯片能够根据系统的需要运行特定的运算。这些系统一般使用消息传递机制来实现软件（运行在CPU和FPGA中）和硬件之间的通信。但是有一个缺点软件需要被写在一个特定的消息传递模式中。文章提出了一个新的轻便的软件和可重构硬件之间的接口。软件端能使用常规方法调用进行复杂计算,这些调用能被拦截和翻译成硬件消息。同样的,在硬件端能够使用软件的方法。这种接口不仅让实现新JAVA/FPGA协同设计变得简单,更重要的是加快了Java程序的运行速度。     

2HL055恒流二极管参数测试

2HL055是贵州博越公司生产的恒流二极管,该类器件恒定电流大,极限电压低,可以直接驱动负载,但器件形成实验室成品后,没有进行过参数测试,其基本参数范围不能确定。文章拟通过试验,进一步测试2HL055器件的基本参数,并确定部分参数的测试方法。