Stochastic Contrast Measures for SAR Data: A Survey

“Contrast” is an generic denomination for “difference”. Measures of contrast are a powerful tool in image processing and analysis, e.g., in denoising, edge detection, segmentation, classification, parameter estimation, change detection, and feature selection. We present a survey on techniques that aim at measuring the contrast between (i) samples of SAR imagery, and (ii) samples and models, with emphasis on those that employ the statistical properties of the data.      

光学期刊联合编辑部成功参展中国国际光电周

第十一届ILOPE展会于2006年12月5-7日在北京召开,此次展会包含了一个光电展览,四个技术/产业论坛和一个中外贸易交流会.吸引了来自14个国家近400家参展商,展出面积达1万多平米.国内主流的激光、光学和红外厂商悉数到场,同时国外FLIR、光谱物理、相干、镭宝、贰陆、HGH、Senko、美国Photonics、尼康等国际知名企业也携新产品、新技术参与.     

Graph Laplacian Matrix Learning from Smooth Time-Vertex Signal

In this paper,we focus on inferring graph Laplacian matrix from the spatiotemporal signal which is defined as“time-vertex signal”.To realize this,we first represent the signals on a joint graph which is the Cartesian product graph of the time-and vertex-graphs.By assuming the signals follow a Gaussian prior distribution on the joint graph,a meaningful representation that promotes the smoothness property of the joint graph signal is derived.Furthermore,by decoupling the joint graph,the graph learning framework is formulated as a joint optimization problem which includes signal denoising,timeand vertex-graphs learning together.Specifically,two algorithms are proposed to solve the optimization problem,where the discrete second-order difference operator with reversed sign(DSODO)in the time domain is used as the time-graph Laplacian operator to recover the signal and infer a vertex-graph in the first algorithm,and the time-graph,as well as the vertex-graph,is estimated by the other algorithm.Experiments on both synthetic and real-world datasets demonstrate that the proposed algorithms can effectively infer meaningful time-and vertex-graphs from noisy and incomplete data.     

8848从顶峰走向衰微的历史见证

人不可能两次迈进同一条河流，而8848却似乎可以。近段时间，因为速达的“收购传闻”，8848再一次成为业界关注的焦点。因为如今的8848内部风雨飘摇，外部官司缠身，它有何被收购的价值?公司总裁吕春维为何早早投怀送抱、急于为收购造势?谁是这一出“收购闹剧”的幕后主使?在诸多疑问背后，很少有人能看清事情本质。老8848的创始人王峻涛知道，但他不说，因为此8848已非当年之彼8848。几年前，盛极一时的老8848就是这样被幕后资本强行拉入分拆和兼并的资本游戏，被胜利冲昏头脑的大股东妄图运用资本力量主导企业发展，对他们来说，更重要的是上市圈钱。但因为牵扯的利益太多，诱惑太多，8848的发展最终陷入极度迷茫中，在资本疯狂追逐最大利益的时候，企业却错过了发展的最佳时机，并从此一步步走向衰微。6年来，8848经历了最辉煌的巅峰时期，同样也经历了无数是是非非。即使当时剩下的钱仍可使8848运营数十年，但是，商人们已经对8848的未来失去了耐心与信心，老8848最终难逃遭清算厄运。后来，所谓“王者归来”的新8848更是虚有其表，连核心业务也惹上纠纷，最后股东终于按捺不住……现在经常有人问王峻涛，如果当时不要上市，如果当时不分拆，如果……但王说：假设没有意义，我懂得了一点：创业者要坚持、坚持、再坚持。张朝阳也说：做自己的，不要听华尔街的。或许这就是本文要寻找的答案。     

中国这样进行专利谈判肯定不行——美国移通半径公司亚太区总裁雷鸣硅谷对话《IT时代周刊》

3G谈判受阻的主要原因是在谈判中，电信研究院作为一家研究机构实力太弱，如果能聘请外国在专利谈判上有丰富经验的律师或律师行主谈，加上中国政府的免费授权政策和运营商有关采购3G设备政策的出台，专利谈判可能是另外一个结果。     

Intelligent Passive Detection of Aerial Target in Space-Air-Ground Integrated Networks

Passive detection of moving target is an important part of intelligent surveillance. Satellite has the potential to play a key role in many applications of space-air-ground integrated networks(SAGIN). In this paper, we propose a novel intelligent passive detection method for aerial target based on reservoir computing networks. Specifically, delayed feedback networks are utilized to refine the direct signals from the satellite in the reference channels. In addition, the satellite direct wave interference in the monitoring channels adopts adaptive interference suppression using the minimum mean square error filter. Furthermore, we employ decoupling echo state networks to predict the clutter interference in the monitoring channels and construct the detection statistics accordingly. Finally, a multilayer perceptron is adopted to detect the echo signal after interference suppression. Extensive simulations is conducted to evaluate the performance of our proposed method. Results show that the detection probability is almost 100% when the signal-to-interference ratio of echo signal is-36 dB, which demonstrates that our proposed method achieves efficient passive detection for aerial targets in typical SAGIN scenarios.     

CDMA直放站干扰案例分析

2007年11月17日22点35分.我站值班人员接到中国联通梅州分公司的电话投诉.称其在梅州城区的多个CDMA基站收到不明信号的干扰.严重影响CDMA用户的正常使用。接到投诉后.我站迅速组织技术力量查找干扰     

信息产业部苟仲文副部长亲临一线指导江西抗寒救灾

2月4日,信息产业部苟仲文副部长深入省内通信运营企业现场查看了机房、通信基站和野外倒塌的电线杆,并召开座谈会,详细了解全省通信行业的受灾情况,指导江西通信业抗灾保通信畅通工作。苟仲文高度评价了江西省通信行业抗灾保通信畅通工作,对全省通信行业广大干部员工在抗雪灾行动中的无私奉献表示感谢,并勉励全省通信行业要继续战斗,做好后期的抗灾工作。     

Boston-Power集资发展新一代锂离子电池技术

Boston-Power公司(Boston-Power,Inc.)是创新便携式电源解决方案的供应商,其解决方案可满足当今市场对更安全、更持久锂离子电池的需求.日前,该公司宣布募集了4500万美元的新资金.C系列融资是由Oak Investment Partners主导,并包括现有的蓝筹投资者Venrock Associates、Granite Global Ventures及Gabriel Venture Partners.     

新起点 新机遇——BIRTV2008吹响广播影视新技术的集结号

2008年7月11日.BIRTV2008筹备工作通报会在北京梅地亚中心召开,广电总局科技司王效杰司长、中央电视台何宗就副台长、中央人民广播电台钱岳林总工、广电总局广播科学研究院马炬院长、广播电视规划院姜文波院长、中央电视台技管办黄平刚主任以及中广国际总公司李金荣总经理等领导出席会议,与120多位参展厂家的代表和媒体界的朋友们在会上进行了座谈.     

数据库性能评测指标及其测试方法研究

近些年来,国产数据库得到了快速的发展,但是针对其性能的测试方法和测试指标却参差不齐。针对上述问题,中国软件评测中心在大量数据库测试的基础之上,参考国际性能评价指标,建立了一套相对完善的数据库性能评价指标,其中主要分为时间特性、资源利用特性和性能标准依从性三大指标,同时分析各指标的特点,应用Loadrun-ner、TPCC等国际通用的测试工具和方法设计了个指标项的测试内容,形成了关于数据库性能特性的评价体系及其评价方法的说明文档,该套体系从性能质量上保证了国产数据库的质量。     

一种测控系统抗干扰性能评估模型

为了对测控通信系统数据传输性能进行客观有效的评估,针对测控系统的测量链路和遥测链路,设计了一种抗干扰性能评估模型。将传输可靠性、频谱效率、功率效率、干扰抑制性能作为抗干扰性能评估指标,在对各评估指标规范化处理的基础上,基于μ律对数压缩方法生成各指标性能和综合性能评价值,并映射成相应的性能评估等级,能够得到测控系统的测量链路和遥测链路中不同的性能指标和总抗干扰性能指标的评估值和评估等级。仿真表明,提出的评估模型可以客观有效地对测控系统的测量链路和遥测链路的抗干扰性能联合进行评估,并通过评估等级直观地反映链路性能的优劣。     

分布式仿真系统实时性实现技术研究

针对分布式仿真系统的结构和特点,阐述了计算实时性、通讯实时性和调度实时性3个方面影响系统仿真实时性的主要原因。对于计算实时性问题,提出基于扩展实时操作系统的多线程技术。对于通讯实时性问题,提出采用UDP协议和共享内存技术;对于调度实时性问题,提出采用硬件和软件同步结合的方法来实现时钟同步。通过实践表明,提出的方法是可行和有效的。     

红外成像系统性能模型的研究进展

综述了国内外红外成像系统性能模型的状况。在分析静态性能模型和动态性能模型的基础上，分别给出了其基本构想，阐述了几种静态性能模型的优缺点，讨论了动态性能模型的三种模块；目标背景模块，图像处理算法模块和目标工作平台模块。介绍了它们在预测现场性能的应用。展望了性能模型的发展趋势。     

部件不可靠下的通信网业务性能分析

分析网络在部件不可靠时的业务性能,通常采用网络状态法,即首先得到不同状态下的性能指标,然后通过状态概率得到平均业务性能.本文将考虑部件可靠性对部件业务性能的影响,提出一种基于不可靠设备业务性能的设备状态法,这相当于仅考虑一个网络状态的业务性能,所以比任何网络状态法简单,而且由于可分析设备失效而中断的业务量,还可以用于分析自愈网的性能.     

Performance Modelling — What, Why, When and How

Management of performance risk is achieved by using performance engineering techniques. A major weapon in the performance engineering armoury is performance modelling. Modelling means prediction — estimating the performance of a new system, estimating the impact of change on an existing system or estimating the impact of a change of workload on an existing system. This paper describes how IT systems performance modelling fits into the overall performance engineering approach and its role in performance prediction and risk management. It then focuses on a recent case study illustrating why a particular modelling technique was used, how it was used, and the outcome of the modelling exercise.     

相控阵雷达中的自适应搜索研究

本文研究了相控阵雷达中的自适应分区搜索算法及性能.首先,推导了最优分区搜索性能及其与均匀搜索性能的关系,分析了目标强度估计误差对最优分区搜索性能的影响;然后,分别研究了平稳目标分布和非平稳目标分布环境下的自适应搜索方法、最优参数和性能.     

数字图像水印性能评估指标的研究

在阐述数字图像水印性能评估方法一般步骤的基础上,提出了数字图像水印的鲁棒性、安全性、透明性、水印容量等几项主要性能评估指标。为了能够进行公平合理的性能评估,必须尽量保证各个水印系统是在相同的条件下进行性能比较。文中所提出的主要评估指标对水印性能的评估起到积极的指导作用;最后对未来的数字水印性能评估进行了展望。     

RF performance degradation in nMOS transistors due to hot carriereffects

This paper reports the hot electron induced RF performance degradation in multifinger gate nMOS transistors within the general framework of the degradation mechanism. The RF performance degradation of hot-carrier stressed nMOS transistors can be explained by the transconductance degradation, which resulted from the interface state generation. It has been found that the RF performance degradation, especially minimum noise figure degradation, is more significant than dc performance degradation. From the experimental correlation between RF and dc performance degradation, RF performance degradation can be predicted just by the measurement of dc performance degradation or the initial substrate current. From our experimental results, hot electron induced RF performance degradation should be taken into consideration in the design of the CMOS RF integrated circuits     

The Satisfaction-Performance Controversy

Current speculation continues to imply that satisfaction and performance are causally related. While the performance-causes-satisfaction proposition is a more recent development, the contention that satisfaction causes performance remains more widely held. Recent research findings, however, offer only moderate support of the former view and reject the latter. The evidence indicates that the relationship is more complex: rewards constitute a more direct cause of satisfaction than does performance, and rewards based on current performance cause subsequent performance. Thus, the manager who wants to improve his subordinates' performance must, first, provide valued rewards of sufficient magnitude and then establish the necessary contingencies between effort and performance and between performance and rewards. Last, he needs to consider a range of nonmotivational factors.