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1.
中国计划向利用国内港口转运货物的出口企业提供税务激励,以从国外竞争对手那里吸引更多货运量.例如,从青岛、武汉起程的出口船只如果利用上海洋山港转运,将可获得退税.这一计划由国务院实施,将针对干散货船和集装箱船展开,以帮助国内港口与邻近的航运中心竞争.  相似文献   
2.
Numerical simulation based on finite element modelling is used to study the influence of welding sequences on the distribution of residual stress and distortion generated when welding a flat-bar stiffener to a steel plate. The simulation consists of sequentially coupled thermal and structural analyses using an element birth and death technique to model the addition of weld metal to the workpiece. The temperature field during welding and the welding-induced residual stress and distortion fields are predicted and results are compared with experimental measurements and analytical predictions. The effect of four welding sequences on the magnitude of residual stress and distortion in both the plate and the stiffener is investigated and their effects on the ultimate strength of the stiffened plate under uniaxial compression are discussed. Appropriate conclusions and recommendations regarding the welding sequence are presented.  相似文献   
3.
船队扩张已被中国的一些新兴船东提上议事日程。据当地的经纪人观察,越来越多的迹象表明,私人船东已在这方面有所动作。尽管不少老牌船东仍在为融资问题而一筹莫展,一批新运营商却已跃跃欲试,将目光投向更多船只,其中就包括珠海新世纪航运、广东粤电航运及舟山中昌海运。据了解,这三家公司前期一直在考察各种散货船,为船队扩张作准备。作为新一代船东的代表,他们有的是野心,而且之前手中已有不少新船在建,融资大多由实力雄厚的母公司或租赁实体提供。  相似文献   
4.
The objective of this study was to investigate the performance of a model azimuthing podded propulsor in ice-covered water. Model tests were carried out with two different depths of cut into the ice (15 and 35 mm), two different ice conditions (presawn and pack ice conditions), and four different azimuthing angles. The depth of cut is the maximum penetration depth of the propeller blade into the ice block. The 0.3-m-diameter model propeller was operated in a continuous ice milling condition. Ice loads were measured by several sensors which were installed in various positions on the model. Six one-axis pancake-style load cells on the top of the model measured the global loads and two six-component dynamometers were installed on the shaft to measure the shaft loads. One six-component dynamometer was attached to the one of the propeller blades inside the hub to measure the blade loads. The pod unit and propeller performance in ice are presented. Ice-related loads, which were obtained when the blade was inside the ice block, are introduced and discussed. During the propeller–ice interaction, a blade can experience the path generated by the previous blade, which is called the shadowing effect. The effects of shadowing, depth of cut, azimuthing angle, and advance coefficient on propulsor performance are presented and discussed.  相似文献   
5.
This article discusses the use of continuous autoregressive models to describe the behavior of traffic indices. From discretely sampled data, second-order differential equation models are constructed to represent dynamic traffic fluctuations as the response of a linear system to a stochastic forcing function. The results are compared to the more common M/G/∞ queueing model approach, and the analysis is demonstrated on time series of aircraft concentration in thirty-one enroute air traffic control sectors.  相似文献   
6.
7.
The burgeoning commitment to contracting the delivery of bus services through competitive tendering or negotiated performance-based contracts has been accompanied by as many contract payments schemes as there are contracts. We are now well placed to design a simplified performance-linked payment (SPLP) model that can be used as a reference point to ensure value for money, given the accumulation of experiences throughout the world which have revealed substantive common elements in contracts. Whether the payment to the operator is framed as a payment per passenger or as a payment per service kilometre, the SPLP identifies efficient subsidy outcomes that are linked to a proxy indicator of net social benefit per dollar of subsidy. We illustrate how the SPLP model can be applied to obtain the gross (subsidy) cost per passenger (or per passenger km) from measures of gross cost efficiency and network effectiveness. This model can then be used as part of a benchmarking activity to identify reference value of money prospects in respect of passengers per $ subsidy outlay by adjusting for influences not under the control of the service provider. A single framework to identify contract payments to operators, and to assess (i.e., benchmark) operator performance on critical KPIs, is provided by internalising critical key performance indicators (KPIs) in the design of the SPLP. The proposed SPLP model is sufficiently general to be independent of the procurement method (competitive tendered or negotiated, for example) and of the treatment of revenue allocation (net or gross based contracts), with the additional advantage of being able to assess value for money for government.  相似文献   
8.
Different from western markets, the margin rates in Chinese futures markets are raised when contract approaches maturity. This paper concentrates on the effect of this time dependent margin rule on volatility. Open interest, another candidate in the margin rule, is also included in our model to investigate its necessity as one of the factors of the rise of margin rates. With the popular copper contract in Shanghai Futures Exchange (SHFE) , our test results suggest that margin levels have a significant positive effect on volatility, yet open interest has little to do with volatility. The implication is that the rise of margin rate approaching maturity virtually deteriorates the degree of market risks, and open interest is not a necessary factor for the margin rule. It indicates that the policy tool, represented by margin rates, has significantly greater influence on volatility than the market element, represented by open interest.  相似文献   
9.
ABSTRACT

A scientific consensus has recently emerged suggesting that the dominant twentieth century paradigm of solving transportation congestion problems by building more freeways failed. The legacy of the freeway construction era is clearly visible in polluted and congested cities worldwide. To battle these ills, planning academics have been promoting more sustainable built form aligned with dedicated public/active transport provision. Partly as a result of the push coming from academia, a number of cities have sought to remove their freeways and replace the freed up space with alternate transport infrastructure, such as streets and boulevards. To discern if the transportation planning profession is currently undergoing a paradigm shift or whether freeway removal is merely a temporary fad, we have conducted a systematic review of the literature. In this article, we unpack the underlying reasons which have led some cities to removing their freeways. Results reveal that a paradigm shift has arguably not yet taken place in transportation planning. While many cities are creating human-scale and active transport spaces, currently these spaces tend to coexist alongside freeways. American cities, which were once the pioneers of freeway construction, appear to be lagging behind cities in Europe and Asia in this respect. If the current pace of freeway removal continues, it may take a few decades before the transportation planners, politicians, policy makers, and communities adopt radically different norms, methods, and goals. However, a radical approach may need to be taken sooner given alarming global warming predictions.  相似文献   
10.
面对经济危机,CSDC决定按照自己的轨道发展,而不是被经济触礁和低迷的言论左右视线。虽然中海发展股份有限公司(CSDC)在亚洲市场扮演着重要角色,但这并不是公司董事总经理茅土家在经济危机之际仍然能沉着、勇敢面对的原因。  相似文献   
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