船舶电气自动化中几个重要技术的应用

对自动化技术在船舶电气自动化领域中应用的几个重要技术——电力电子技术在船舶轴带发电和电力推进系统中的应用、CAN网络在船舶电站自动化系统中的应用及船舶电站自动化系统可靠性保障技术的应用等进行探讨。     

2.25Cr-1Mo钢TIG堆焊Fe_3Al合金的研究

通过TIG堆焊工艺试验,建立了填充金属含铝量与Fe-Al合金堆焊层含铝量之间的对应关系,研究了含铝量对堆焊层裂纹倾向、显微组织,力学性能及断裂特征的影响规律,确定了获得Fe3Al合金堆焊层所要求的焊丝含铝量范围,为研制开发Fe3Al堆焊焊丝提供了依据.     

大型导管架平台的建造与安装

随着海上油气开发的日趋成熟,对大型海洋平台的需求量越来越大.而对于海洋平台,不管是建造还是安装都存在着困难.由于平台较重,建造时需要有足够承载力的场地,需要大型的吊车进行作业.安装时需要大型的浮吊,而目前我国最大的浮吊吊装能力有3 800 t,对于超过5 000 t的平台来说,一般采取将平台分成几部分分别建造和安装的方法,这样给平台的海上安装带来了一定的困难,并大幅度增加了海上的工作量.文章简要介绍了这种大型导管架平台的建造与安装.     

JCT型灌缝胶在圆管涵加固中的应用

JCT型灌缝胶强度高、收缩小，有着良好的力学性能。用于维修补强混凝土结构，施工简单方便，在桥板（梁）和涵洞加固补强中日益得到了广泛的应用。文章主要介绍了圆管涵裂缝的原因及采用高渗透性、高粘结强度的灌缝胶修复混凝土裂缝和加固补强圆管涵的施工技术。     

准三维波生近岸流数学模型在裂流研究中的应用

阐述了一种考虑波流耦合作用的准三维近岸流模型SHORECIRC。该模型耦合了REF／DIF波浪模型（折／绕射模型）对近岸流进行模拟计算。基于该模型，将模拟结果与Borthwick等人在英国海岸工程研究所做的实验进行对比，验证了模型的正确性和适用性。在此基础上，进一步分析了波浪入射波高、入射角度、底摩阻及驼峰高度对裂流的影响，得出了一些有用的结论。     

区域物流系统成长水平测度模型研究

为测度区域物流系统成长水平,在将物流系统分为物流功能系统、物流网络系统、物流需求系统的基础上,构建了包括物流企业竞争力、货物周转量等13项指标构成的测度指标体系,并用熵权法确定了各评价指标的权重.采用综合指数评价法对区域物流成长水平进行评价,构建区域物流成长水平测算模型.通过计算序参量成长指数推算子系统成长指数,测度物流系统成长水平.模型应用于环渤海地区,其中山东的物流系统成长水平最高,成长水平最低的是河北省,原因在于其区域物流需求子系统得分较低.结果表明,模型能较为客观地测度区域物流系统成长水平,识别物流系统薄弱环节,为物流系统完善提供建议.     

基于Logistic模型的城市慢行交通出行者特性研究

为了防治机动车污染,提升慢行交通系统使用率与服务水平,针对慢行交通出行者特性开 展研究。以铜川市居民出行调查为数据基础,将其分为家庭属性、个人属性与出行特征属性3 个 类别,借助SPSS 软件构建二元Logistic 模型,以优势比（OR） 为主要评判标准,从多种属性变 量中辨识影响慢行交通使用的主要变量,阐述出行者特征。研究结果表明：步行出行距离一般小 于3km,自行车出行距离小于5km,各种属性变量对慢行交通的选择有不同程度的影响,步行与 自行车出行的影响变量也存在差异;女性更倾向于步行而男性使用自行车的几率更高;非通勤出 行以步行为主;交通工具保有量的提升会降低步行使用率,而对自行车出行基本不产生影响;家 庭收入与是否选择慢行交通出行不存在显著关系。     

Research on High Power Inter-Channel Crosstalk Attack in Optical Networks

While all-optical networks become more and more popular as the basis of the next generation Internet(NGI)infrastructure,such networks raise many critical security issues.High power inter-channel crosstalk attack is one of the security issues which have negative effect on information security in optical networks.Optical fiber in optical networks has some nonlinear characteristics,such as self phase modulation(SPM),cross phase modulation(XPM),four-wave mixing(FWM)and stimulated Raman scattering(SRS).They can be used to implement high power inter-channel crosstalk attack by malicious attackers.The mechanism of high power inter-channel crosstalk attack is analyzed.When an attack occurs,attack signal power and fiber nonlinear refractive index are the main factors which affect quality of legitimate signals.The effect of high power inter-channel crosstalk attack on quality of legitimate signals is investigated by building simulation system in VPI software.The results show that interchannel crosstalk caused by high power attack signal leads to quality deterioration of legitimate signals propagated in the same fiber.The higher the power of attack signal is,the greater the fiber nonlinear refractive index is.The closer the channel spacing away from the attack signal is,the more seriously the legitimate signals are affected by attack.We also find that when attack position and power of attack signal are constant,attack signal cannot infinitely spread,while its attack ability shows a fading trend with the extension of propagation distance.     

Reliability Analysis of Retracting Actuator with Multi-State Based on Goal Oriented Methodology

In order to conduct effective reliability analysis of retracting actuator with multi-state(success state,safety failure state and action failure state), we redefine type-3 operator in goal oriented(GO) method to describe three states of main charge of retracting actuator and improve type-15 operator in GO method to describe the logic relations of multi-state output. The quantitative and qualitative reliability analyses of retracting actuator are made based on GO method in this paper. The system state probability of retracting actuator is obtained through quantitative analysis, and its weakness is found through qualitative analysis. The analysis results show that GO method is effective to improve the reliability of retracting actuator, and this method is also feasible for reliability analysis of other complicated initiating explosive systems.     

径向激励作用下有限长双层圆柱壳声振传递特性研究

文章利用Donnel壳体方程描述双层圆柱壳振动,以附加阻抗的形式表示环肋、实肋板以及水介质等对壳体的力作用,结合内外壳振动位移模态展开形式,建立了双层圆柱壳内外壳之间的声振传递矩阵。同时开展了双层圆柱壳外壳均方速度响应仿真分析,验证了双层圆柱壳内外壳振动响应之间存在固定的传递关系,不受激励源特性影响,为双层圆柱壳辐射噪声预估提供了一定的理论指导。