红外光谱辐射计的研制

介绍了红外光谱辐射计的组成及工作原理,分析了其信号处理方法。红外光谱辐射计的核心是分光元件、光学系统及信号处理部分。该设备采用容易调整的高像质反射光学系统和波长在２５～１４μｍ连续可变的分光系统,并采用高集成度、高精度的数据采集、数字锁相和数据处理、存储系统。观察瞄准、探测接收的光学系统以及数据采集、处理系统都被放到一个体积很小的测量头中,具有体积小、质量轻牢固可靠、抗干扰性能强和使用方便等优点。入瞳的最小可探测率为１０－１２Ｗ／ｃｍ２,光谱分辨率为２％,测量速度为１０条谱线／ｓ。经实际检测和使用,该设备的性能达到国内外先进水平,并具有野外工作的特点。     

实用型智能化模拟生态箱

介绍模拟生态箱的自控系统及模拟生态功能,实用型智能化模拟生态箱是一个能自动控制温度,湿度,光照的密封透明箱体,可以用来缩短农作物等植物科学研究的时间和周期,具有现实意义意义和明显的经济效益和社会效益。     

全国短波监测网络系统的设计与实现

阐述了一种全国短波监测网络系统的设计与实现方案。该系统实现了短波监测的实时监测和非实时监测功能，实现了频谱数据、台站信息的管理和与国家无线电管理中心数据库无缝链接的功能，并具有自动控守扣报警功能。此外，还实现了与ARGUS无线电监测软件XML接口的链接，满足了异构监测数据交换的需求。系统采用模块化结构，由一系列标准模块组成,具有良好的可维护性和可扩展性。     

主流电子交易网站账户安全登录模式缺陷与安全设计

账户的使用是互联网的基础应用之一。由于传统账户登录方式存在极大的安全隐患,不少大型电子交易网站如银行、淘宝等逐步采用了安全控件登录的方式。文章对安全登录、传输以及身份认证过程进行了分析,指出了其中存在的重放攻击漏洞,提出了采用时间戳的公钥登陆安全模型来解决漏洞的方法。     

FPC市场与技术展望

该文叙述了挠性印制板在电子设备中应用,市场的重点,电子设备对挠性印制板的要求以及技术发展趋势。     

调Q脉冲YAG三波长激光诱导液相沉积Si基Ni-Pd-P纳米膜

使用脉冲三波长Nd：YAG激光实现了室温下半导体硅上化学沉积Ni-Pd-P纳米膜。SEM结果表明,激光诱导化学沉积Ni-Pd－P纳米膜具有良好的选择性。经STM测试发现,由于激光作用,镀层不仅沿表面生长,而且在厚度方向上也不断增厚。极化曲线测试表明,短时间激光诱导沉积的Ni-Pd-P纳米膜具有优异的析氢催化性能。     

Delay time in GaAs high-power photoconductive switches

The delay time defined as the time interval between the beginning of optical illumination and the onset of switching in photocurrent in gallium arsenide (GaAs) high-power photoconductivity switches is studied on the basis of electroabsorption caused by absorption edge shifting due to bandgap narrowing. The influences of the initial open-state field, the laser wavelength and the temperature are given. The results show it is the reflection and the transmission of the switch semiconductor slab indicated by the absorption fraction express the absorption rate of the illumination energy by the switch     

An Airborne Radar Clutter Tracking Algorithm Based on Multifractal and Fuzzy C-Mean Cluster

For an airborne Iookdown radar, clutter power often changes dynamically about 80 dB with wide distributions as the platform moves. Therefore, clutter tracking techniques are required to guide the selection of const false alarm rate （CFAR） schemes. In this work, clutter tracking is done in image domain and an algorithm combining multifractal and fuzzy C-mean （FCM） cluster is proposed. The clutter with large dynamic distributions in power density is converted to steady distributions of multifractal exponents by the multifractal transformation with the optimum moment. Then, later, the main lobe and side lobe are tracked from the multifractal exponents by FCM clustering method.     

Ultra-Wideband Electrostrictive Mechanical Antenna

Mechanical antennas based on piezoelectric materials can effectively reduce the size of long wave antennas down to 1/1000 of the wavelength (from km scale to mm level). However, the narrow bandwidth and weak field intensity seriously restrict its practical applications in transmission distance and channel capacity. Here, a mechanical antenna-based electrostrictive effect of relaxor ferroelectric ceramic (PMN-PT) is proposed to improve radiation capacity and achieve ultra-wideband characteristics (10 kHz–1 MHz). Due to the ultra-high dielectric constant at working temperature and the relationship between the strain and applied field intensity, the proposed antenna gets rid of the dependence on the poled materials and exhibits excellent communication properties beyond traditional mechanical antennas, which are experimentally demonstrated by a practical wireless communication system. Only using a single proposed mechanical antenna with 8 mm diameter and 3 mm thickness, the effective communication with a transmission distance of 200 m can be realized. This design offers a promising way of constructing mechanical antennas for long-wave communication.     

恶意代码分析技术综述

随着全球信息化的不断推进,整个世界越来越被连成一个整体,威胁计算机系统安全的领域也越来越广泛,其中以恶意代码最为严重。而随着计算机系统安全攻击与防御技术的不断较量,恶意代码的攻击手法、攻击形式也越来越趋于隐秘化、复杂化。因此,有必要对当下的恶意代码分析技术进行总结,从中发现新的发展方向,以应对不断变化的恶意代码形势。