隧道掘进机产业化及发展方向

研究目的:为适应隧道掘进机广阔的应用前景,必须实施隧道掘进机产业化,本文对隧道掘进机产业化模式及发展方向进行探讨。研究方法:通过对隧道掘进机产业化意义、产业化成果、产业化方式和产业化模式的分析和论证;提出适合于中国国情的产业化发展方向。研究结果:提出了产业化发展的方向和实现产业化的途径。研究结论:隧道掘进机产业化宜以施工企业为主,通过组建施工、设计、制造、科研四位一体的隧道掘进机产业化联盟,建立和完善产业化基地,实现隧道掘进机的自主开发和成套提供的总体目标。     

太平洋航线集装箱货流量GM(1,1)-马尔可夫链预测方法探讨

运用灰色系统理论对太平洋航线集装箱货流量进行定量预测,并结合马尔可夫预测方法对航线运量进行定性分析,达到定量与定性预测相结合的目的,使预测结果更加合理。采用马尔可夫链划分系统的状态,得出状态转移概率矩阵,分析了太平洋航线集装箱货流量的发展变化区间并预测集装箱航运市场的发展前景。     

进口高性能吊链在铁路装卸作业中的应用

根据北京铁路局组织的进口高性能吊链、钢丝绳及国产吊链的性能对比试用结果,分析了进口吊链在装卸作业中应用的优点与不足之处,提出了使用时的安全注意事项。     

ON STRONGLY REGULAR RINGS

TheVonNeumannregularringsaredis-cussedinRef-[lj.Weherediscussstronglyreg-ularringsbytheideaofsemigroupandcanob-tainsomenewresults.Definition1[lJRingRiscalledstronglyregularring,ifitsatisfiesoneofthefollowingequivalentconditions:(1)Risaregularring,andeveryidempotentelementisacenterelement.(2)ForeveryaeR,thereexistsxsuchthata=a2x.(3)RisaregularringandRisreduced.Definition2L2]Cliffordsemigroupisareg-ularsemigroup,anditsidempotentisacenterel-ement.Hencewehavethefollowingtheorem:Theorem1IfSi…     

从供应链管理看现代物流对我国航运业的影响

在海洋运输的基础上,全面介入物流服务,积极配合货主对运输服务更高层次的要求,以货主为中心全面提高门到门运输的服务水平,将给航运企业自身带来多方面的竞争优势。事实表明,从海洋运输向综合物流服务转变,已经成为国际航运企业发展的大方向。本文介绍了现代物流的供应链管理、“双赢”及“多赢”战略,以客户为中心等理念在航运业中的应用情况;结合大量的例子,从供应链管理角度分析我国航运存在的问题,并探讨解决问题的措施。     

基于供应链的现代集装箱码头管理

在全球供应链下,作为国际物流重要节点的集装箱码头也面临着激烈的竞争和挑战。在此情形下,以集装箱码头为中心,整合国际海运物流渠道,构建集成化的集装箱码头供应链,将现代供应链管理的思想应用到集装箱码头生产营销中,无疑是集装箱码头走出当前困境、提升自身竞争力的关键。     

Policy innovations of the US intermodal surface transportation efficiency act and clean air act amendments

In combination, the Intermodal Surface Transportation Efficiency Act of 1991 (ISTEA) and the Clean Air Act Amendments of 1990 (CAAA) are innovative and aggressive efforts to move US cities toward integrated transportation and air quality planning. Under these complementary laws, air quality has become a major national transportation goal. In areas with serious air pollution, air quality will be a major consideration in determining the future shape of urban transportation.This paper considers how the CAAA and ISTEA combine to provide an innovative national policy approach of interest to countries seeking to encourage sustainable development in urban centers. The CAAA mandates measurable and enforceable air quality targets. Nation-wide standards are set for acceptable levels of carbon monoxide, ground level ozone, and small particulates. ISTEA includes directions for transportation planners and decision-makers to follow to reach air quality and other goals — transportation planning must emphasize system efficiency, and for cities with severe air pollution, transportation projects are expected to contribute to cleaner air. Each urban area has flexibility in how it applies this framework to reflect its priorities and solve its problems. Strict federal sanctions provide incentives for compliance with both laws.Enactment of these laws has produced a period of transition and uncertainty as well as of challenge and opportunity for planners and elected officials. The next several years, the US will provide one national laboratory and over 100 different urban laboratories for innovative approaches to integrate transportation and environmental policies to resolve major urban problems.Abbreviations CAAA Clean Air Act Amendments of 1990 - CO Carbon monoxide - ECO Employee Commute Option - EPA US Environmental Protection Agency - HC Transportation hydrocarbons - I/M Inspections and maintenance program - ISTEA Intermodal Surface Transportation Efficiency Act of 1991 - MPO Metropolitan planning organizations - NO_x Nitrogen oxides - PPM Parts per million - PM₁₀ Small particulate matter - SIP State Implementation Plan - TIP Transportation Improvement Program - TCM Transportation control measures - VMT Vehicle miles traveled     

锚泊时船舶放链长度的确定及其实用图表

本文给出了船舶锚泊时所受到的风作用力、水作用力和放出锚链长度的计算公式,以及实用数表和曲线图,可供查取。数表和曲线是根据文中确定的如下关系式编绘:L_b≈1/2Ln;L≈1.5L。(其中L_b——卧底锚链长度;L_n——悬垂锚链长度;L——放出锚链总长度)。十一例实船计算表明,根据上式计算结果,与目前国内外通用的方法确定的放链长度相符。利用这些数表和曲线图,既可合理地确定不同海况下船舶所应放出的锚链长度,也可减少起锚时的功率消耗和缩短起锚时间。     

造船供应链合作利益分配协商机制研究

造船供应链合作利益分配过程是个群体协商过程.文章基于供应链节点企业间风险共担、利益共享的合作特点,分析了利益分配应遵循的原则.并充分考虑各节点企业的投资额、承担的风险及分配方案满意度,应用不对称Nash谈判模型设计了造船供应链合作利益分配的协商机制.     

MEAN SHIFT尺寸链在某车型尾灯优化中的应用

尾灯板的结构形式直接影响尾灯匹配,为了减少尾灯定位孔尺寸链,文章提出了一种考虑MEANSHIFT的尺寸链分析方法,在设计前期对尾灯板结构进行优化。以某车型尾灯板结构优化为例,通过尾灯安装定位孔位置分析出该设计存在的风险,针对风险,提出调整定位孔位置的解决办法,使新结构尾灯孔偏差低于原结构,通过现场验证,证明该方法可行。