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61.
62.
对中国现行出租车市场行政审批、拍卖、定额招标等主要准入模式存在的弊端进行了分析,指出出租车市场准入与退出机制应促进服务质量竞争,促进企业自身建设,促进运营模式改革,并维护行业稳定,建立一个以服务质量招投标为主要手段的出租车市场准入与退出机制,对实施服务质量招投标制度需解决的政策法规配套、服务质量评价体系构建、经营权有偿使用制度改革以及新老政策衔接等关键问题提出了建议。实际应用表明该机制可以较好地化解政府、出租车公司、出租车驾驶员之间的利益矛盾,促进行业自身建设,加强行业服务竞争,提高行业服务水平。 相似文献
63.
公路工程监理市场面临的问题与解决的措施 总被引:1,自引:0,他引:1
分析了公路工程监理市场存在的问题及问题产生的原因,针对性地提出了解决问题的措施。 相似文献
64.
This paper investigates whether deficiencies detected during port state control (PSC) inspections have predictive power for future accident risk, in addition to other vessel-specific risk factors like ship type, age, size, flag, and owner. The empirical analysis links accidents to past inspection outcomes and is based on data from all around the globe of PSC regimes using harmonized deficiency codes. These codes are aggregated into eight groups related to human factor aspects like crew qualifications, working and living conditions, and fatigue and safety management. This information is integrated by principal components into a single overall deficiency index, which is related to future accident risk by means of logit models. The factor by which accident risk increases for vessels with above average compared to below average deficiency scores is about 6 for total loss, 2 for very serious, 1.5 for serious, and 1.3 for less-serious accidents. Relations between deficiency scores and accident risk are presented in graphical format. The results may be of interest to PSC authorities for targeting inspection areas, to maritime administrations for improving asset allocation based on prediction scenarios connected with vessel traffic data, and to maritime insurers for refining their premium strategies. 相似文献
65.
Po-Hsing Tseng 《Maritime Policy and Management》2018,45(4):422-438
As Arctic sea ice shrinks due to global warming, the Northern Sea Route (NSR) and the Northwest Passage (NWP) offer a substantial reduction in shipping distance between Asia and the European and North American continents, respectively, when compared to conventional routes through the Suez and Panama Canals. However, Arctic shipping routes have many problems associated with their use. The main objective of this paper is to identify the key criteria that influence the decisions of shipping operators with respect to using Arctic shipping routes. A multi-criteria decision-making methodology, the Fuzzy Analytic Hierarchy Process, is applied to rank four potential categories of criteria (‘economic’, ‘technical’, ‘political’ and ‘safety’ factors) and their sub-criteria.
The results of the analysis suggest that, on aggregate, ‘economic’ is the most important category of influential factors, followed by ‘safety’, ‘technical’ and ‘political’ factors. The paper concludes, however, that the most influential specific sub-criteria relate to risks that lie mainly within the ‘safety’ and ‘political’ domains and that, especially in combination, these overwhelm the importance which is attached to ‘economic’ factors such as reduced fuel use. Finally, the implications of these findings for the future development of Arctic shipping are addressed at a strategic level. 相似文献
66.
The most frequently associated options in the physical shipping market are options to extend the charter period on time charters and additional shipment options on contracts of affreightment. The value of freight options, in practice, is estimated mostly by referring to forward curves. An option on freight has different properties from its financial counterparts, and the straightforward adoption of theoretical models does not produce promising results. In this paper, extension options, which have the property of options on futures, were transformed into regular European options before the application of the Black-Scholes model (BSM). The efficient market hypothesis, which justifies the parity of the performance of a long-term charter to that of repetitive short-term charters, worked as the basis for the transformation. The option values determined by the BSM were compared with actual realized values. Additionally, the artificial neural networks (ANN) was employed to derive the option values. This study is meaningful as the first-time application of both the closed-form solution and the ANN to the valuation of physical freight options. The research results can contribute to the quality of chartering decisions. The results could also be used in quantifying credit risk, as extension options tend to be granted to charterers with more creditability. 相似文献
67.
Flex-Lay铺管船是柔性管线铺设平台,通过分析全球Flex-Lay铺管船发展现状,Flex-Lay铺管船正向专业化和多功能化方向发展,为我国Flex-Lay铺管船发展提供借鉴。 相似文献
68.
69.
Wei X.Liu X.Duan Y.Feng J.Qiao N.Guo L. 《现代隧道技术》2018,(3):220-228
Water-sealed underground oil tank projects are quite different from traditional underground projects since the water-sealing conditions are very strict and the difficulties caused by the geological specificity, structural specificity and construction specificity are key factors affecting the project. In light of the significant early initial setting time and rapid temperature increase of sulphoaluminate cement-based grouting material for a large domestic water-sealed underground oil tank with pressurized cyclic grouting, a laboratory grouting simulation is conducted. It is found that the properties of the sulphoaluminate cement-based grouting material are quite different under different pressure cycles, the hydration exothermic peak time gets shorter with an increase of circulation time, the compressive strength decreases with an increase of circulation time, and the longer the circulation time the more obvious the de-crease of compressive strength. © 2018, Editorial Office of "Modern Tunnelling Technology". All right reserved. 相似文献
70.
Shuaian Wang 《Maritime Policy and Management》2017,44(1):62-80
This study examines how to incorporate the inventory costs of containerized cargoes into existing liner service planning models such that the designed networks could be improved while not causing extra modeling/computational burden. Two approaches are compared: (i) not considering the inventory costs at all and (ii) incorporating the inventory costs associated with onboard time and those related to transshipment by assuming a fixed connection time. The two models are compared with the ideal model capturing the exact inventory costs on a route choice problem and a capacity planning problem based on extensive randomly generated and practical numerical experiments. The results show that: first, ignoring the inventory costs in service planning models may lead to network design with much higher costs (poor network design decisions); second, in service planning models assuming weekly frequency, the inventory costs associated with onboard time could be formulated exactly, and those related to the connection time of weekly services could be approximated by assuming fixed connection time of 3.5 days for ports with 1 day’s minimum connection time and 4.5 days for ports with 2 days’ minimum connection time. 相似文献