Autonomous community construction and coordination technology to achieve real-time transmission in multiple emergencies’ situation

Wireless Sensor Network (WSN) is used in Emergency Management System (EMS). If emergency situation happens, real-timely transmitting emergency information in dynamically changing environment should be assured. But this requirement could not be satisfied by conventional approaches which are based on static situation and centralized management. In this paper, to satisfy this requirement, autonomous community construction technology is proposed for single emergency. Emergency information could be transmitted in community and protected from interference of other information’s transmission. Moreover, autonomous coordination technology is proposed for multiple emergencies’ information’s transmission. Via this technology, each emergency could have its individual route to transmit emergency information. Each emergency information’s transmission will not influence with each other. Evaluation results are provided to demonstrate the improvement.     

基于单演信号理论的SAR图像配准

该文提出一种基于单演信号理论的SAR图像配准的新算法。利用单演信号局部特征构造一个单演相位一致函数,用来检测SAR图像特征。利用单演信号分量构造单演向量,通过求单演向量相关,解决SAR图像特征点的匹配问题。实验结果显示,算法能较好完成SAR图像自动配准。     

一种基于偏振光干涉的原子力显微镜测头的研究

为了提高测头的抗干扰能力,达到较高的分辨率,设计了一种基于偏振光干涉原理的原子力显微镜测头。该测头采用偏振光干涉式方法探测针尖的位移,可提高测头的灵敏度。分析了测头设计中焦点聚焦在探针悬臂梁上的可行性,并通过实验进行了验证。实验表明,Wollaston棱镜组可以有效地改变光程差。设计的共光路形式的Nomarski干涉仪光路,能够有效减小噪音的影响,并保证装置结构紧凑,适于实用。通过实验验证,此测头系统能够达到1nm的纵向分辨精度,为原子力显微镜测量技术提供有力支持。     

高校学生宿舍管理系统的分析与设计

高校宿舍是高校的一个重要组成部分,近年来随着各大高校扩招规模的加大,高校学生宿舍管理系统的分析和设计显得尤为重要,它不但能够加快高校宿舍管理与社会主义现代化学校管理机制接轨,而且还可以保证高校学生宿舍管理的有序性和安全性。利用高校学生宿舍管理系统能够减轻人工操作的繁琐,为高校步入现代化管理模式管理办学做好充分地准备。     

A 1.65μm three-section distributed Bragg reflector （DBR） laser for CH4 gas sensors

A 1.65-μm three-section distributed Bragg reflector(DBR) laser for CH4 gas sensors is reported.The DBR laser has a wide tunable range covering the R3 and R4 methane absorption line manifolds.The wavelength tunability properties,temperature stability and laser linewidth are characterized and analyzed.Several advantages were demonstrated compared with traditional DFB lasers in harmonic detection.     

A Parallel Platform for Web Text Mining

With user-generated content, anyone can De a content creator. This phenomenon has infinitely increased the amount of information circulated online, and it is beeoming harder to efficiently obtain required information. In this paper, we describe how natural language processing and text mining can be parallelized using Hadoop and Message Passing Interface. We propose a parallel web text mining platform that processes massive amounts data quickly and efficiently. Our web knowledge service platform is designed to collect information about the IT and telecommunications industries from the web and process this in-formation using natural language processing and data-mining techniques.     

Design of inverse class-E amplifier with finite D.C. feed inductance

This paper reports on a design of inverse class-E amplifier with finite D.C. feed inductance. The finite D.C. feed inductance is resonated by the parallel capacitance at the fundamental frequency. The direct design equations required to determine the optimum operations are derived in detail. Comparing with the classic inverse class-E amplifier, numerical results show that improvements in minimizing size, cost, and complexity of the circuit can be obtained by the inverse class-E topology with finite D.C. feed inductance. Comparing with the sub-harmonic and parallel-circuit class-E amplifiers, the inverse class-E topology with finite D.C. feed offers advantages for MMIC realization. Theoretical analysis is validated by numerical simulation and measurement. Excellent agreement between theory and simulation results is achieved. Comparison between simulations and measurements of an experimental circuit validate the feasibility of the design. A measured output power of 40.01 dBm, with a drain efficiency of 80.16% and power-added efficiency of 78.93% were obtained at 250 MHz with a 22-dBm input power.     

某型车载电台强电磁脉冲环境效应仿真和试验

为检验某型车载通信超短波电台在高空核电磁脉冲环境下的生存能力,对该型电台建立全尺寸模型,进行了电磁脉冲耦合仿真分析,对比了该电台鞭状天线的前门耦合以及各互连线缆的后门场线耦合电流量级,得到前门耦合大于后门耦合的结论.结合仿真结果,对电台的强电磁脉冲环境适应性试验方法进行了设计,并采用威胁级辐照方法,采用垂直极化的电磁脉...     

The electron transport properties in a three-barrier structure based on monolayer graphene

Using the transfer matrix method, we theoretically investigate the electron transport properties in a three-barrier structure based on monolayer graphene. The numerical results show that the transmission probability and the conductance strongly depend on the barrier height, the barrier width and the incident energy as well as the incident angle of carriers. Therefore, by changing the configuration of the structure, the electron transport properties can be adjusted to be suitable for the practical application in various graphene-based electronic devices such as the graphene-based transistor with the high on/off ratio and the direction-dependent wave vector filter.