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961.
张倞 《铁道货运》2006,(11):41-42
对目前专用线装卸车存在的问题进行分析,从严格货车使用费的收取、签订专用线卸车应急协议,加强专用线考核、促使企业加强专用线技术设备改造等方面提出了提高  相似文献   
962.
This paper summarizes work undertaken towards development and calibration of a model to predict the distribution of rail freight traffic among competing routes. The model is designed for use in analyzing the traffic effects of changes in the level-of-service on selected rail lines. The model predicts route shares based on the overall network configuration of each railroad participating in a given market. The model selects feasible routes, discards those routes which appear to be too circuitous or costly, and then assigns traffic to the remaining routes in accordance with several network characteristics. It is designed to be sensitive to level-of-service changes, and to simulate the response of shippers and railroads to a competitive environment. A multiple route-finding algorithm was used to find possible routes based on the number of railroads operating at the originating and terminating end of a market. Multiple routes were determined and matched with observed traffic flows from the ICC One-Percent Waybill Sample. Physical network characteristics for each route, including distance, junction frequency, and “impedance,” were calculated from the network model and were correlated with the traffic share observed on each route in the market. A two-stage model was developed to find feasible routes from the set of possible routes and to allocate traffic to feasible routes based on levels-of-service. The model was calibrated on 9,793 routes from 1,199 markets with twenty or more carloads from the 1977 One-Percent Carload Waybill Sample. Model calibration supported the hypothesis that network route characteristics did indeed influence shipper choice of route, and that a normative model could be used to assess relative attractiveness of routes under various railroad corporate ownership restructuring scenarios.  相似文献   
963.
梁靖 《天津航海》2005,(2):34-36
在海牙规则和美国海上货物运输法下,货物承运人要负责照管货物,并可能对货物的灭失和损害负责。本文主要关注在舱位共享协议普遍存在的情况下,租船合同下签发提单时,美国法院如何判断哪一方是承运人。并讨论关于集装箱货位租赁中有关承运人问题的司法判例会对承运人援引美国海上货物运输法下的责任限制产生何种程度的影响。  相似文献   
964.
本文给出一种利用微型机实现城市轨道车辆最佳运行的控制方案,即在变化的外界条件下确定断电和制动时刻,以指导司机驾驶车辆,实现能耗最小和准时运行.该控制方案的特点是不断地利用实测值并结合估算确定断电和制动时刻,简单易行.  相似文献   
965.
Knowledge of future traffic flow is an essential input in the planning, implementation and development of a transportation system. It also helps in its operation, management and control. Time series analysis techniques have been extensively adopted for this purpose in the fields of economics, social sciences and in other fields of technology. An attempt has been made in this study to apply the techniques of time series analysis to goods traffic, particularly truck traffic. Four predominant corridors, N.H.3, N.H.4, N.H.8 and Lal Bahadur Shastri Road (L.B. S. Rd.), accounting for majority of truck movement in the Bombay Metropolitan Region (BMR), have been considered for modeling. Raw data was processed initially, to obtain an insight into the structure of time series. Ten candidate models of the Auto-Regressive Moving Average (ARMA) and Auto-Regressive Integrated Moving Average (ARIMA) family are investigated to represent each of the four corridors. Models finally proposed, to represent each of the four corridors have been selected based on Minimum Mean Square Error (MMSE) and Maximum Likelihood Rule (MLR) criteria. Models ARIMA (2, 1, 0), ARMA (1.0), ARMA (1, 1) and ARIMA (1, 1, 0) are proposed for N.H.3, N.H.4, N.H.8 and L.B.S. Rd. respectively, based on significant weekly periodicity.  相似文献   
966.
通过介绍秦沈铁路客运专线六股河特大桥32.0 m单线箱梁预制的施工实例,阐述了32.0 m后张法预应力单线箱梁的施工模具的设计、工艺装备、原材料选定、混凝土灌注及张拉等一整套施工技术.  相似文献   
967.
The emergence of a safety culture in shipping has been promoted, especially by the Secretary General of the International Maritime Organization. However, what is really meant by a safety culture? The adoption of the International Safety Management Code and of the amended International Convention on Standards of Training, Certification and Watchkeeping for Seafarers, STCW 95, together with the introduction of Formal Safety Assessment in the IMO rule making process are considered as the major tools contributing to the emergence of such. This article examines the evolution of the concept of maritime safety concept during the last decades and discusses how the adoption of new international instruments has contributed to improve the maritime safety system. It provides possible definitions of maritime safety and safety culture and discusses how far the maritime safety system is from a culture of safety.  相似文献   
968.
北京市铁路噪声特性实例分析研究   总被引:6,自引:0,他引:6  
通过实际测量及数据分析,认为测量现场昼夜等效声级达到 777 d B( A),超过了国家标准;快速列车噪声频谱分布复杂,难以治理;列车鸣笛对铁路噪声超标贡献最大,验证了铁路噪声与列车车速的关系,最后提出控制铁路噪声的建议。  相似文献   
969.
分析了个人独资企业、合伙企业的特征。从企业的资产、负债、所有者权益、会计报表等几个方面探讨了个人独资企业和合伙企业会计制度的制定对策。  相似文献   
970.
Rail fares in South-East England have been increasing in real terms for several years, and are expected to continue to do so. In this paper, the impact of such increases is examined in terms of the choices of mode of travel, home and job location, and residential migration. Forecasts are made using a model in which the population is partitioned into four sets according to whether they have changed home and/ or job over the forecast period. The model allocates population to homes and workers to jobs, and commuters to the three modes of travel considered. The impact of an increase of 25% in real fares over a five-year period is examined and a number of conclusions are drawn. The model shows that rail patronage will decline even if transport costs remain constant in real terms, because of decentralisation of jobs and rising car ownership. The overall long-term rail fare elasticity is found to be –0.7, but this is the mean of a wide range of values for different parts of the study area. People ceasing to commute by rail would divide almost equally between car and bus, the latter being used particularly to Central London. Those people who commute to London who are seeking new homes would tend to choose to live nearer London than they would have otherwise. The paper concludes with a discussion of the findings in terms of the assumptions implied in the model.  相似文献   
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