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91.
介绍了车辆动态模拟装置在评价车辆乘坐舒适性方面的应用情况,并阐述了车辆动态模拟装置在车辆部件研发过程中的重要作用.  相似文献   
92.
汽车产品的质量总是会受到巨大的关注。质量较差会导致财务成本的增加,这使得制造商把提升质量作为一项商业必要的手段。过去的数年中有无数方法和流程被用来减少浪费和消除缺陷 (比如6-Sigma法和TQM完全质量管理法)。我们并不缺少这样的衡量工具,来衡量因质量问题和返工而产生的负面经济效益。运用这些衡量工具能够理解质量对每辆车或者公司的盈利能力造成的影响,并且帮助公司取得显著的产品质  相似文献   
93.
This study investigates determinants of the vessel, cargo, and other-property damage costs of bulk barge accidents in US inland waterways. Tobit estimation of a three-equation recursive model suggests that, in bulk barge accidents: (1) vessel damage cost is greater for collision, fire/explosion, and material/equipment failure accidents than for groundings; (2) cargo damage cost is greater at night and when the weather is foggy and increases with barge age; and (3) otherproperty damage cost is greater for multi-vessel accidents, but decreases with barge size. A dollar of vessel damage cost increases other-property damage cost by $1.38, while a dollar of cargo damage cost increases this cost by $6.90. An important result for formulating bulk barge accident cost-reduction policies is that a given determinant might have a negative effect on one type of damage cost but a positive effect on another.  相似文献   
94.
Developments in UK shipping: the tonnage tax   总被引:1,自引:0,他引:1  
The new UK Government, elected in May 1997, came to power with a commitment to reverse the decline of the UK shipping industry and enhance the employment prospects of UK seafarers. The Government commissioned Lord Alexander of Weedon to investigate the case for a tonnage tax. In this paper, the economic arguments for supporting the UK shipping industry are reviewed. There is some evidence that the UK holds a comparative advantage in world markets in key sectors of the shipping industry and on-shore maritime related activities, but is being undermined by lower foreign taxes. In the absence of government support, the UK shipping industry is likely to continue to decline, and, by further reducing the supply of qualified UK ex-seafarers, put at risk the successful on-shore activities. Various measures that might be used to support a national shipping industry, e.g. a tonnage tax, are considered. The paper concludes by discussing the likely impact of the tonnage tax on the UK's shipping industry.  相似文献   
95.
Upon the expiry of the concession contract signed between Lebanon and a private company for the Port of Beirut operation (in December 1990), the Government appointed a temporary commission to operate the port under the rules of the expiring concession. The legality of this measure has since always been questioned, while the temporary commission underwent three major personnel changes which clearly prevented any long-term thinking or planning. In 1998, the temporary commission entered into a 20-year joint venture for the establishment of a container terminal. Meanwhile, Lebanon's two main ports were facing major regional competition, while competing against each other to some degree. Thus, the need became urgent to end the temporary status and propose reforms to the entire sector. To that end, the Ministry of Public Works and Transport was commissed by the Government to propose a permanent institutional framework for the port of Beirut while assessing the need for a national maritime sector regulator. This paper presents the recommendations for the institutional reform of the Lebanese maritime transport sector.  相似文献   
96.
A time-domain technique for estimating wave-induced ship hull bending moment from ship motion measurements is presented. This technique is developed to improve hull response monitoring systems. Artificial neural networks are used to model the time-domain relationship between the wave-induced vertical bending moment and the coupled heave and pitch motions. The application of the proposed technique is validated using experimental data.  相似文献   
97.
每次看到一台精密的基于示波器技术的现代检测工具.我们都会想到老一辈的汽修技师们,感叹他们当时是怎样利用简陋的检测工具和不太靠得住的简单的故障诊断测试方法进行工作的。同样地.当他们了解了一些新的检测工具后.肯定也会感叹融入新技术的检测工具给汽车维修工作带来的巨大便利。[编者按]  相似文献   
98.
Dynamics of inorganic nutrient species in the Bohai seawaters   总被引:3,自引:0,他引:3  
Within the frame of a Sino-German Joint Research Program, two cruises of “R/V Dong Fang Hong 2” were carried out in September–October 1998 and April–May 1999, respectively, to understand the dynamics of nutrients in the Bohai. Nutrient species (NO3, NO2, NH4+, PO43− and SiO32−) are determined colorimetrically on board for five anchor and 30 grid stations. In situ incubation experiments are performed to determine planktonic nutrient uptake and benthic exchange flux. Nutrient concentrations display short-term variability and seasonal change in the Bohai, with higher levels in shallow coastal waters than in the Central Bohai. The influence of riverine discharge on nutrient levels can be seen from salinity isopleths, nutrient distribution and species ratios. Near-bottom (nb) waters have similar nutrient concentrations as to the surface waters in the Central Bohai, whereas stratification takes place in the Bohai Strait and North Yellow Sea. In situ incubation experiments provide evidence that the uptake ratio (i.e. N, P) by phytoplankton is proportional to the ratios among nutrient species in ambient waters. Based on the data of this study and previously publications, a preliminary estimate of nutrient budgets via riverine input and atmospheric deposition is established. The results indicate that atmospheric deposition gains importance over rivers in delivering nutrients into the Bohai and sustain the new production, following recent decrease in riverine inflow caused by drought periods in North China and damming practices. A historical review of nutrient data indicates that concentrations of nitrogen increase and phosphorus and silica decrease in the Central Bohai over last 40 years. This potentially has an important influence on the health of ecosystem in Bohai (e.g. food web and community structure), though further study is needed to examine the scenario in more detail.  相似文献   
99.
铁路乘客艾滋病知识、态度、行为调查分析   总被引:2,自引:0,他引:2  
目的 调查铁路旅客的艾滋病相关知识、态度和行为情况,为列车开展艾滋病宣传教育提供理论依据。方法 对6趟旅客列车乘客进行抽样问卷调查,调查结果进行统计分析。结果收回有效调查问卷2 083份,艾滋病一般知识正确回答率55.83% ~92.03%,传播途径59.67%~93.52%,临床知识59.00%~77.34%,预防控制68.75%~88.86%,态度行为48.25%~94.33%,政策法规67.64%~84.88%。正确回答率无性别差异(P>0.05);一般知识、传播途径、行为态度存在结婚与否的差异(P<0.05);受教育程度上除一般知识外,其它都有显著性差异(P<0.01)。结论 铁路乘客对艾滋病知识、态度、行为的正确回答率,原则性问题高于具体问题, 71%以上乘客愿意接受健康教育和AIDS教育。针对铁路乘客流动性强的特点,列车上艾滋病宣传教育内容要注重知识具体化。  相似文献   
100.
This paper described the process of generating the optimal parametric hull shape with a fully parametric modeling method for three containerships of different s...  相似文献   
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