校园无线局域网的安全性研究

介绍了校园无线局域网的优势和问题所在.分析了WLAN(Wireless Local Area Network)IEEE802.11系列安全协议的工作方式,和各自的缺陷.提出了利用Linux内核空间下的Neffilter框架,动态加载IPSec处理模块的方法,构建了一个IPSec VPN网关,以解决无线网络的安全问题,同时也能实现在线实时的信息交换和共享.     

世界钻井船市场发展现状

从钻井船的船龄结构、建造年份、船东、运营商、建造商,设计型式、作业水域、工作水深、钻井深度等方面论述了钻井船市场现状,展望了钻井船市场的未来发展。指出虽然在未来一两年内世界钻井船新船订造市场仍可能较为谨慎,但由于未来世界深海油气的开采对于钻井船的大量需求,钻井船建造市场的长期走势仍值得期待。     

营业线电化区段中型桥移梁施工方案的优选

在营业线电化区段进行桥梁移梁施工涉及范围广,施工难度高,对列车正常运输干扰大,对施工方案的要求较高.通过对京广线淤泥河桥移梁工程施工方案的优选,较好地解决了施工中遇到的问题,对既有线移梁施工有一定的借鉴作用.     

Mainstream Encounters the Dilemma Posed by Non-main Stream

In 2009,the global shipping and shipbuilding markets are loitering around in the"coldest winter".Though they display better than we image after"big adjustment"of stagnate,no obvious resuscitation has been seen,and the mainstream position of shipbuilders,shipowners and ship type in fOrmer days is also changing.     

船舶远程识别与跟踪(LRIT)进展概况

一、船舶远程识别与跟踪(LRIT)概述船舶远程识别与跟踪(Long-Range Identificationand Tracking of Ships,简称LRIT)通过从船载自动识别系统(AIS)提取船舶识别码、船位和时间等数据,并利用全球海上遇险和搜救系统(GMDSS)的Inmarsat-C或高频设备(HF)以固定的时间间隔发送LRIT数据,经计算机对数据处理,实现船舶的远程识别与跟踪。LRIT由船     

广西山区公路填石路堤路床用料的探讨

本文根据广西山区石山地区公路施工的特点,结合实际施工经验分析探讨石山地区填石路堤用料的使用情况,从技术,经济,环保的角度阐述了用碎石作为填石路堤路床用料的可行性。     

Test Scenario Design for Intelligent Driving System Ensuring Coverage and Effectiveness

Intelligent vehicle greatly benefits traffic safety, efficiency and driving comfortable. With the development of intelligent driving technology and its application, it is becoming increasingly important to do effective and comprehensive tests before putting on the market. Comprehensively considering the cost of test, an automatic generation method of test scenarios is proposed to ensure both coverage and effectiveness. Based on the analyzed key infuence factors of an intelligent driving system, the analytic hierarchy process (AHP) is used to determine their importance and accordingly an complex index is defined, based on which an improved test case generation algorithm based on the pairwise independent combinatorial testing tool (PICT) is proposed to ensuring both combinational coverage and complexity of test cases. Finally, the test scenario is generated by clustering these discrete test cases considering similarity and complexity. The high complex test cases are preferred to be combined together and conducted preferentially to increase the test efficiency. The effectiveness of this method is validated by applying it on a lane departure warning system (LDW).     

一种基于Top-hat算子的小目标图像预处理方法

针对微弱二维离散信号的检测,即图象中弱小目标的检测,本文介绍了一种基于数学形态学滤波的小目标图像预处理方法,Top-hat算子是在数学形态学开运算、闭运算基础上推导出来的一种算子,Top-hat算子可以检测到图像中的高频分量,而滤去图像中灰值变化相对较为平稳的地方,利用Top-hat算子可以对一幅单帧图像进行滤波,去掉小目标图像中的大面积背景,实验证明,该方法起到了比较好的效果。     

不同结构形式无碴轨道施工对比分析

针对《京沪高速铁路设计暂行规定》中推荐的板式、弹性支承块式和长枕埋入式三种无碴轨道结构形式 ,结合工程实例 ,对其设计特点、施工方法、适用范围、工程造价及施工进度作对比分析。     

新型电力机车自动抄表系统的解决方案

介绍电力机车自动抄表系统的作用、构成、各部分的设计方法,阐述分段计量的实现方法,并与AVL系统中GPS/GSM技术的应用方式进行比较.