广州地铁1号线通信传输系统--OTN传输网络

广州地铁1号线通信系统采用德国西门子公司生产的设备,该系统共有8个子系统,分别是传输子系统(OTN)、程控交换机(PABX)、无线(RADIO)、广播(PA)、电视(CCTV)、网络管理(NMS)和不间断电源     

基于安卓的汽车状态测量及预测系统的研究

设计了基于Android(安卓)的汽车运动状态在线测量及预测系统,阐述了预测系统的硬件组成和软件设计方法。通过实车道路试验,对侧向加速度与横滚角的试验值与预测值进行比较,并得出相对误差率,验证了该预测系统的可行性。与传统车载终端相比,该预测系统不仅提高了安卓车载终端对汽车主动安全的融合性,而且有效降低了汽车状态感知的成本并具有良好的可扩展性和灵活性。     

Numerical Investigation of the Dynamics for Low Tension Marine Cables

This paper presents a numerical investigation into the dynamics of marine cables which are extensively used in offshore industry. In this numerical study, the Euler-Bernoulli beam model is adopted to develop the governing equations of the cable. Bending stiffness is considered to cope with the low tension problem in local area of towing cable, and thus a more accurate solution with the consideration of the axial elongation can be given.The derived strongly-coupled and nonlinear governing equations are solved by a second-order accurate, implicit,and large time step stable central finite difference method. The quadratically convergent Newton-Raphson iteration method is applied to solving the discrete nonlinear algebraic equations. Then a towed array sonar system(TASS)problem is studied. The numerical solutions agree reasonably well with the experimental data and the simulated results of the references. The specified program of the present paper shows great robustness with high efficiency.     

A Two-Stage Feature Selection Method for Text Categorization by Using Category Correlation Degree and Latent Semantic Indexing

With the purpose of improving the accuracy of text categorization and reducing the dimension of the feature space,this paper proposes a two-stage feature selection method based on a novel category correlation degree(CCD)method and latent semantic indexing(LSI).In the first stage,a novel CCD method is proposed to select the most effective features for text classification,which is more effective than the traditional feature selection method.In the second stage,document representation requires a high dimensionality of the feature space and does not take into account the semantic relation between features,which leads to a poor categorization accuracy.So LSI method is proposed to solve these problems by using statistically derived conceptual indices to replace the individual terms which can discover the important correlative relationship between features and reduce the feature space dimension.Firstly,each feature in our algorithm is ranked depending on their importance of classification using CCD method.Secondly,we construct a new semantic space based on LSI method among features.The experimental results have proved that our method can reduce effectively the dimension of text vector and improve the performance of text categorization.     

“海马”号4500米级ROV系统研发历程

作为国家863计划重点项目"4500米级深海作业系统"的主要研究成果,"海马"号4500米级无人遥控潜水器(ROV)于2014年2~4月在南海成功完成了海试。"海马"号是我国自主研发的第一套大深度ROV系统,最大工作水深4500m,主要作业功能是进行海底探测、取样以及其他水下作业。"海马"号的研发和海试成功是我国海洋技术领域继"蛟龙"号后的又一个标志性成果。介绍了"海马"号ROV的立项背景、研究目标、系统组成、总体技术性能和功能及其研发历程和海试情况。     

长江航运辉煌的“十五”

“十五”期长江干线港口货物吞吐量年均递增速度高达23．2％；2003、2004、2005年分别突破3亿、4亿和6亿t大关；2005年，长江干线货运量达到7．95亿t，是2000年的1．65倍，长江成为世界上运量最大的通航河流。     

半刚性沥青路面路用性能参数演化机理分析

依托沈阳—大连高速公路多年路况普查测定的大量数据,依据可靠性数学的基本理论并运用数理统计的方法,编制了分析程序,对高速公路沥青路面使用性能各参数的概率分布模型、变异水平以及演化规律进行了较全面的研究分析,并得到许多重要结论,可为高速公路沥青路面性能评价预测、可靠性分析以及相关理论研究提供有价值的参考。     

侨城东站用电量与客流量关系分析

以深圳地铁1号线侨城东站2008年5月15日～7月16日用电量和客流量为变量,分析了两者的动态关系:首先,通过Johansen和Juselius的极大似然法对两个变量进行了协整检验,结果显示两个变量之间可能存在动态均衡关系;其次,通过Granger因果检验对两者进行了检验,证明这两个变量间存在因果关系,他们之间是长期均衡关系.客流量的变化会引起用电量的变化,但用电量的变化不会引起客流量的变化.及时疏导乘客,减少乘客在车站的滞留时间会带来电站能耗的大大减少.     

上海崇明越江通道工程环境地质问题及其防治

上海崇明越江通道工程是长江河口地区重要的国家基础性建设项目,所在区域不良地质条件易给工程施工带来不利影响。文章阐述软土变形、水土突涌、水下砂体运移、浅层天然气、岸带冲淤、砂土液化、地面沉降等环境地质问题及其潜在的工程危害,提出相应的防治对策与技术措施。     

工程量清单计价模式下的工程造价控制

从招标过程、合同签订、施工过程3个方面阐述工程量清单价模式下工程造价控制的方法，对不平衡报价提出了针对性预防对策，给出了合同签订时风险防范应对措施和施工过程中造价控制的方法。