供应链环境下销售商的风险分析及评估

利用风险因素分析和多级模糊综合评估相结合的方法进行风险评估,建立相应模型,进一步用风险系数量化销售商风险的大小.     

Simulation of unsteady free-surface flow around a ship hull using a fully coupled multi-phase flow method

An accurate, efficient algorithm for solving free surface flows around ship hulls is described. Accuracy is achieved using a compressive advection discretization which maintains a sharp free surface interface representation without relying on a small time step. Efficiency is obtained using a solution algorithm which implicitly couples velocity, pressure, and volume fractions. The algorithm has been implemented in a computational fluid dynamics code called CFX and is validated by means of a comparisonwith experimental data of benchmark cases in both steady and transient conditions.     

摩托车燃油蒸发排放测试方法简介(3)

(上接2007年第7期) 2.2.2密闭室法 a)昼间换气损失:1)摩托车以50 km/h匀速运行至少10 km以上,或按CNS 11386-D3165连续行驶10次以上(预处理规定与美国加州不同).2)在(25±5)℃室温放置6～36 h.3)预处理试验用燃油.4)燃油放干净,注入油温低于15.5℃、放置量为油箱实际容积(50±2.5)%的试验油.5)加装测试用温度传感器.6)摩托车放置在温度为(25±5)℃密闭室内.7)试验开始前,标定分析仪.8)使用电热带,按规定升温曲线加热油箱(美国加州标准中不区分外露式和非外露式油箱;台湾燃油蒸发排放标准中油箱加热曲线有2条,其中外露式油箱加热曲线与美国加州相同).     

利用全站仪进行曲线放样

介绍GPS测量受限时利用全站仪进行曲线放样的原理、有关公式的推导、计算方法、操作步骤及与GPS测设的精度比较。     

合宁客运专线列控的相关思考

合宁客运专线于2008年4月18日正式开通运营,目前设备运行基本稳定.由于合宁线是我国首条客运专线,其设备构成代表未来我国客运专线的方向.所以有必要对该线采用的列控设备CTCS-2级列控系统进行相关说明.     

关于铁山支线多条专用线接轨后联锁设备方案的选择

铁山支线位于淄博市临淄区金岭镇西部,从胶济线金岭镇站接轨至铁山站,区间线路全长约6.5 km。在该支线周围有大量的厂矿企业,先后有7家企业修专用线。由于多家专用线接轨,     

交通仿真技术在交通事故研究中的应用

交通事故研究对于个人和整个社会都具有重要意义。简述了交通问题的研究方法,并以仿真软件TSIS中的FRESIM模型,分析研究高速公路中的事故黑点对交通特性及环境的影响。另外,通过采用不同的管理措施,进行事故间接经济损失分析。     

A comparative analysis of the European and North-American approaches to dealing with major oil spills

Background  

The question of what should be the right level of preparedness to react to a major oil spill (i.e. the EXXON VALDEZ spill, the ERIKA spill, and the PRESTIGE spill) is highly debated, especially in the aftermath of such spills. Little research, however, has been conducted with the aim to identify and compare governments’ best practices not only to fund preparedness measures but also to assess the countries’ ability to respond effectively to catastrophic oil spills. It is the author’s belief that important lessons can be learnt from a comparative analysis of countries’ best practices.     

我国摩托车燃油蒸发排放国家标准GB 20998-2007的制定与研究(2)

(上接2008年第3期) 实施生产一致性检查试验的关键是生产企业要严格组织生产,控制采购、检验等过程和环节,如果某一车型不满足生产一致性检查要求,应尽快采取有效措施重新建立生产一致性,否则撤销该车型的型式核准.     

Numerical analysis of crack under compression by 3D displacement discontinuity method

A 3D displacement discontinuity method is applied to solve the fracture mechanics problems of the mixed mode crack under compression. Friction between the surface of the closed crack is considered by establishing a simple and efficient iterative algorithm based on method of contact resistance mitigation. On the surfaces of the closed crack, the Mohr-coulomb rule is satisfied by iteration when the crack is in condition of sliding. The stress intensity factors are obtained using displacement fitting method. It is shown that the numerical results agree with the experimental results well and that friction plays an important role in resisting crack propagation.