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David A. Hensher 《Research in Transportation Economics》2010,29(1):106-117
In the transport sector, many types of contracts exist. Some are very precise, and strive for completeness; others are very ‘light-weight’ and are incomplete. Bus and coach contracts, won through competitive tendering or negotiation, are typically incomplete in the sense of an inability to verify all the relevant obligations, as articulated through a set of deliverables. This paper draws on recent experiences in contract negotiation, and subsequent commitment in the bus sector, to identify what elements of the contracting regime have exposed ambiguity and significant gaps in what the principal expected, and what the agent believed they were obliged to deliver. We develop a series of regression models to investigate the extent of discrepancy between the principal and the agents perceived ‘understanding’ of contract obligations. The empirical evidence, from a sample of bus operators, is used to identify the extent of perceived incompleteness and clarity across a sample of bus contracts. A noteworthy finding is the important role that a trusting partnership plays in reducing the barriers to establishing greater clarity of contract specification and obligations, and in recognition of the degree of contract completeness. 相似文献
134.
This paper reviews a number of themes that have played a crucial role in the debate on alternative contracting regimes for the provision of urban bus services. We have selected four crucial issues to reflect on: (i) contractual regimes (in particular competitive tendering as compared to negotiated performance-based contracts, as means to award the rights to provide service); (ii) contract completeness (focussing on ex ante and ex post elements); (iii) building trust through partnership; and (iv) tactical or system level planning for bus services. Experience in these areas suggests that competitive tendering has frequently not lived up to expectations and that negotiation is likely in many circumstances to deliver better value for money. 相似文献
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Bus fires are a common source of fires that occur in tunnels and are a huge threat to the safety of the tunnel structure and related personnel. An elaborate numerical simulation model of a bus is established considering the different combustion characteristics of the bus body, seats, decorations and baggage. For fires occuring at the bus head, middle part or back seat, the temperature field, heat release rate (HRR) and characteristics of the fire are ana-lyzed. The HRR calculation formula is obtained by superimposing a Boltzmann curve on a Gaussian curve. The re-sults show the peak and average values of a bus HRR are 48 MW and 8.1 MW, respectively, and the released energy due to combustion is 14.5 GJ; the maximum burning temperature reaches 1 040℃ and the temperature near the door can reach 60℃ after 120 sec. The temperature rises fastest at the bus door when the fire occurs at the rear of the bus and it has a high chance of detonating the fuel tank. © 2018, Editorial Office of "Modern Tunnelling Technology". All right reserved. 相似文献
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高速USB数据采集系统的设计严格遵循USB2.0协议,实现了主机和测试设备之间简单、快速、可靠的连接和通信.该文介绍了这种数据采集系统的硬件组成、驱动程序和固件程序的设计以及采用虚拟仪器软件LabWindows/CVI在VISA技术上开发应用程序的设计方法. 相似文献
138.
摘要:对当前车联网的发展背景进行简要介绍;并对OBD诊断技术、CAN总线技术、SAEJ39进行了较为详细的研究;提出了基于SAEJ1939的一种车联网无线诊断模块,并就模块硬件设计及应用进行了的阐述。 相似文献
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Madhav G. Badami Murtaza Haider 《Transportation Research Part A: Policy and Practice》2007,41(10):961-981
Maintaining and enhancing public transit service in Indian cities is important, to meet rapidly growing mass mobility needs, and curb personal motor vehicle activity and its impacts at low cost. Indian cities rely predominantly on buses for public transport, and are likely to continue to do so for years. However, the public bus transit service is inadequate, and unaffordable for the urban poor. The paper explores the factors that contribute to and affect efforts to improve this situation, based on an analysis of the financial and operational performance of the public bus transit service in the four metropolitan centres and four secondary cities during the 1990s. Overall, there were persistent losses, owing to increasing input costs and declining productivity. The losses occurred despite rapidly increasing fares, and ridership declined. The situation, and the ability to address it, is worse in the secondary cities than the metropolitan centres. We suggest a disaggregated approach based on the needs and motivations of different groups in relation to public transit, along with improved operating conditions and policies to internalize costs of personal motor vehicle use, to address the challenge of providing financially viable and affordable public bus transit service. 相似文献
140.