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41.
This paper presents a case study which tackles a general problem for railway management, namely the formulation of a strategy to improve business financial performance. This is prefaced, in Section 2, by discussion of general principles - concerning the type of information system required, investigations to be conducted and associated measurement needs. The case study, of Section 3, concerns our investigations of VicRail's total business and its constituents. The task of financial improvement is revealed from an assessment of sectors' current cost-recovery positions and the identification of system joint costs. For freight sectors, future traffic prospects, pricing possibilities and the scope for more efficient operations are then considered, and the implications traced for overall deficit reduction and the development of business strategy. The concluding section draws some general lessons for railway managements.A fuller discussion by the authors of the theoretical framework employed, and particularly of the case study application, is contained in a complimentary publication: Improving Railway Financial Performance, published by Gower in January 1985.Transmark is a subsidiary of the British Railways Board, acting as its international consultancy. The authors, who were respectively study director and manager, wish to thank Bernard Warner (an independent consultant), Richard Eccles (of Transmark) and Adrian Balkyn-Rackowe (of British Rail) for their valuable contributions. The study report, titled Rail Cost — Pricing Options, was released by the Minister in April 1981. 相似文献
42.
从上世纪90年代早期到目前为止,尼日利亚联邦政府并没对航运业和造船修理业投入太多精力。一个典型例子就是,由于对这些行业不够重视导致了前尼日利亚国家货运公司(NNSL)的衰败及倒闭。1996年,尼日利亚联合货运公司(NUL)成立。但新公司的成立并 相似文献
43.
王渤洪 《变流技术与电力牵引》2006,(1):46-53
ICE 系列新动车ICE3、ICET、ICE TD采用了层级结构的诊断系统COBRA(Central On Board RailwayAssistant车载辅助中心),有各装置的自诊断和动车有关的上一级诊断.COBRA诊断系统有清晰的目标群取向,总是只向车务人员和维修人员提供重要的信息和可能的补救措施.在列车进段之前就对自动释放和经无线传输的诊断数据做了计算.列车一进段就准备好了维修人员和维修材料,例如更换损坏件和磨耗件,在进行清洁作业的同时为列车下一次运行准备好了良好的状态. 相似文献
44.
45.
Objective To explore the risk association of ABCA1-V771M polymorphism with coronary heart disease (CHD) in Hart nationality in Northwest of China. Methods With case-control study, ABCA1-V771M polymorphism was detected in 204 unrelated Hart nationality people in Northwest of China, and all the subjects by coronary angiography were grouped into 106 cases and 98 controls. The genotypes and alleles frequency distribution of ABCA1-V771M polymorphisms were analyzed by PCR-RFLP analysis, and the clinical statistics of serum lipids were compared and its effects of ABCA1-V771M polymorphism on the plasma lipid levels and coronary atherosclerotic heart disease were analyzed. Results The genotypic frequencies of ABCA1-V771M polymorphism matched well under Hardy-Weinberg equilibrium (P>0.05), V and M allelic frequencies were 33.3% and 66.7%. In comparison with VV VM genotype carriers, MM genotypes carriers had much lower plasma levels of HDL-C (P<0. 001) and much higher plasma levels of TG (P<0. 05). M allelic frequency in CHD group was significantly higher than V allelic frequency (P<0. 05). M allele was related with more severity of atherosclerosis in the coronary artery than V allele (P<0.05). However, there was no obvious difference in the incidence of AMI among carriers with three genotypes of ABCA1-V771M polymorphism (P>0.05). Conclusion ABCA1-V771M polymorphism was not only associated with the plasma levels of HDL-C and TG, but also related to the susceptibility and severity of coronary atheroselerotic heart disease. Moreover, M771 allele appeared to be atherogenie among Han population in Northwest of China. 相似文献
46.
D. B. Sonawane K. Narayan V. S. Rao S. C. Subramanian 《International Journal of Automotive Technology》2011,12(5):697-704
Most commercial vehicles such as buses and trucks use an air brake system, often equipped with an S-cam drum brake, to reduce
their speed and/or to stop. With a drum brake system, the clearance between the brake shoe/pad and the brake drum may increase
because of various reasons such as wearing of the brake shoe and/or brake drum and drum expansion caused by high heat generation
during the braking process. Hence, to ensure proper functioning of the brake system, it is essential that the clearance between
the brake shoe and the brake drum is monitored. In this paper, we present a mathematical model for the mechanical subsystem
of the air brake system that can be used to monitor this clearance. This mathematical model correlates the push rod stroke
transients and the brake chamber pressure transients. A kinematic analysis and a dynamic analysis of the mechanical subsystem
of the air brake system were performed, and the results are corroborated with experimental data. 相似文献
47.
Margarida C. Coelho Marco B. Luzia 《Transportation Research Part D: Transport and Environment》2010,15(8):443-450
This paper analyzes the energetic performance of the hybrid Lexus RX 400h, through on-board measurements. Several speed profiles were analyzed, for three driving types, successive stop and go cycles, three speed profiles, crossing an electronic toll collection booth, and a roundabout. In stop and go situations the internal combustion engine did not work (the torque needed to impulse the vehicle in the stop and go situations was only supported by the electric engines), as well as in the situations of constant low speeds (50 or 60 km h?1). The auxiliary support given by the electric engines in the accelerations, as well as the importance of the energy regeneration system on the batteries’ load recovery is also demonstrated. When compared with similar conventional vehicles, the Lexus RX 400h has lower combined energy consumption between 1.2% and 60%. 相似文献
48.
Joanne Ellis Björn Forsman Susann Gehl Uwe Langbecker Kurt Riedel Pierre C. Sames 《WMU Journal of Maritime Affairs》2008,7(1):133-149
Commercial shipping of containerized goods involves certain risks for human safety and environment. In order to actively manage these risks, they must be identified, analyzed, modeled, and quantified. This requires a systematical analysis of design and operation of container vessels. Within the EU-funded research project SAFEDOR, a Formal Safety Assessment has been applied to establish the current safety level of generic container ships and to identify potential cost-effective risk control options. This paper describes a structured approach to develop the underlying high-level risk model. It is structured as risk contribution tree consisting of a series of fault trees and event trees for the major accident categories. Statistical analysis of casualty data is used to estimate the probability of occurrence. Finally, the summation overall individual risk contributions yields the current risk pro file for the operation of container vessels is presented as FN-curve. 相似文献
49.
Development of hot stamped center pillar using form die with channel type indirect blank holder 总被引:1,自引:0,他引:1
H. S. Choi B. M. Kim K. J. Nam S. Y. Ha S. H. Cha C. G. Kang 《International Journal of Automotive Technology》2011,12(6):887-894
The hot stamping process has been used in the automotive industry to reduce the weight of the body-in-white and to increase
passenger safety via improved crashworthiness. However, defects such as fracture and wrinkle occur when hot stamping is performed
using a conventional drawing or forming method. In this study, a channel-type indirect blank holder (CIBH) is proposed to
develop a high-strength center pillar in form-type hot stamping, so that the aforementioned drawbacks are overcome. This type
of blank holder plays an important role in reducing severe wrinkling at the flange; such wrinkling leads to folding after
the completion of form-type hot-stamping. First, we investigated the effect of the channel shape on the indirect blank holding
force by using a simplified two-dimensional plane-strain stamping process. Second, we selected the slope angle and corner
radius of the channel as the main shape parameters by finite element analysis and artificial neural network (ANN). It is known
that fracture at the hot formed wall and wrinkle at the flange are significantly affected by the slope angle of the channel,
and the appropriate value for eliminating fracture and wrinkle is determined to be 99°. By performing hot stamping using a
form die with the selected channel, we can manufacture a high-strength center pillar without wrinkle and fracture. 相似文献
50.
This paper provides statistical evidence in support of the view, widely held in the tanker industry, that there are systematic differences in the degree of risk involved in investing in tankers of different sizes, and in operating tankers in spot and time charter markets. The industry view, broadly supported by the results of this paper, is that larger vessels are 'risker' assets than smaller vessels, and operating vessels in the time-charter market is less risky than employing them on a spot basis. The results are obtained by using a method derived from the financial economics literature, which models both the conditional mean and variance of a variable, known as GARCH modelling. Only one other paper has applied this method to the tanker market, and these results provide confirmatory support of those findings. 相似文献