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191.
指出在轨道平顺性测量中轨道检查仪关键器件陀螺仪存在的局限性,通过理论验证,提出一种新的替代方法,即采用传统的长度测量传感器对转角进行测量。通过理论推导,给出新方法的测角数学模型,同时分析了不同基本弦长下其应用的相关问题,以拓展解决此类问题的思路。  相似文献   
192.
介绍郑州地铁1号线车辆的总体设计情况,包括车体、转向架、车门、空调及采暖通风、制动系统、牵引系统、内装方案及车载通信系统等车辆关键部件的选型设计。该方案的技术特点和科技创新主要包括:轻量化全焊接铝合金车体、成熟可靠先进的转向架平台、车体C型导槽+悬挂座方案、双冗余方式的车门控制、制动电阻地面化设计、4台辅助逆变器并网供电、集中供电的LED照明系统、高效节能型环保空调等。  相似文献   
193.
结合西安地铁建设特色,从施工技术方面阐述文物、黄土、地裂缝三大工程难点的技术攻关成果,从建设管理角度介绍工程安全管理和当前风险控制的成功经验.  相似文献   
194.
This study adopted a 5-year moving average to calculate the transition probability of deck officers in Taiwan from 1993–1998 at different levels in the hierarchy. An absorbing Markov transition matrix was also constructed to forecast the terms of seniority and the annual supply of deck officers. In addition, this work applied the GM (1,1) model of Grey theory to forecast the annual demand of deck officers, and used cross analysis to investigate the manpower supply and demand of ocean deck officers in Taiwan. Results in this study can provide a valuable reference for pertinent authorities when determining the manpower policy of shipping companies in Taiwan.  相似文献   
195.
This papers examines the different choices of High Speed Craft (HSC) hull design available and briefly looks at the advantages and disadvantages of each hull form. The trends in various design aspects of HSC such as speed, capacity and size are studied. An investigation on the HSC development is conducted and the future of HSC in the UK is studied. A study onboard an HSC with the aim of trying to determine what passengers think of HSC and why they travel by them is also conducted. Finally, an analysis of the possible market for HSC is carried out.  相似文献   
196.
ABSTRACT

The container shipping industry is receiving growing attention in driving the performance of global supply chains. This phenomenon has accelerated supply chain integration (SCI) within the industry. Although SCI could offer numerous benefits, it is often quoted to be implemented easier in theory than in practice. The high failure rate that is associated with SCI is often not addressed in the literature. Grounded on resource-based view (RBV) theory, this paper is aimed at identifying the critical success factors (CSFs) and examining their influence on SCI and supply chain performance (SCP). Survey questionnaires were administered on 164 container shipping firms. The constructs were validated empirically using confirmatory factor analysis and were subsequently analysed using structural equation modelling. The proposed CSFs in this study are found to be positively corelated with SCI, which, in turn, is positively correlated with SCP. This paper has contributed to both theory and practice by applying RBV theory to identify the key resources and capabilities that are necessary for SCI in the container shipping industry.  相似文献   
197.
Shenzhen Port (SZP), once a negligible local port, has risen dramatically to a world-leading container port and an “equal” player with Hong Kong Port (HKP). Will this market share reallocation continue, or will equilibrium be eventually realized for HKP to prosper continuously? We examine the relationship between these two ports to answer this question. We propose a new transformation method to describe the growth of container cargo transport demand, define the quantitative measures of the competition relationship and port competitiveness, and present a rigorous analytical framework with econometric tests and models to understand the true relationship between HKP and SZP. Direct empirical tests suggest that SZP complements HKP; however, the two ports exhibit strong competition when the effect of demand growth is excluded. Considering transshipment separately, we find that the impact of SZP on HKP is negative in transshipment but complementary in direct shipment. We may conclude that HKP does not affect SZP, whereas SZP has competitive power over HKP. These results are consistent with the findings of some previous theoretical studies.  相似文献   
198.
结合满足美国EPA07排放要求的某大型客车发动机排气后处理系统的设计,分析后处理系统的布置设计、悬置设计,以及后处理系统的测试过程和结果.  相似文献   
199.
长沙地铁芙蓉广场站到五一广场站盾构区间左线接收井和联络线底板高差1.6 m,无法采用传统方法接收和空推前移,通过盾构滚轮接收和盾构铰接研究,采用CAD模拟后用混凝土把接收井回填成竖曲面与联络线标准段进行过渡到后铺设导轨,巧用盾构铰接装置和在底部拼装管片实现大坡度曲面接收前移。拆除连接桥与后配套连接下部螺栓后拆除临时拼装管片,铺设过渡导轨和在盾尾后部导轨上按设可移动反力装置实现了盾体和后配套在联络线底板上直接铺设导轨就能快速空推前移。  相似文献   
200.
北京地铁8号线中国美术馆站采用浅埋暗挖法,在砂卵石地层中下穿四通热力小室,同时上穿6号线盾构区间。介绍了注浆加固措施,对管线采取了深层沉降监测和分层沉降监测技术,较好地控制了热力小室、6号线盾构区间结构变形及地表沉降。  相似文献   
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