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11.
Abstract

The history of urban traffic control (UTC) throughout the past century has been a continued race to keep pace with ever more complex policy objectives and consistently increasing vehicle demand. Many benefits can be observed from an efficient UTC system, such as reduced congestion, increased economic efficiency and improved road safety and air quality.

There have been significant advances in vehicle detection and communication technologies which have enabled a series of step changes in the capabilities of UTC systems, from early (fixed time) signal plans to modern integrated systems. A variety of UTC systems have been implemented throughout the world, each with individual strengths and weaknesses; this paper seeks to compare the leading commercial systems (and some less well known systems) to highlight the key characteristics and differences before assessing whether the current UTC systems are capable of meeting modern transport policy obligations and desires.

This paper then moves on to consider current and future transport policy and the technological landscape in which UTC will need to operate over the coming decades, where technological advancements are expected to move UTC from an era of limited data availability to an era of data abundance.  相似文献   
12.
Australia port reform initiatives have taken on a variety of forms — from out-right sale and transfer of ownership, to the sale of particular assets of infrastructure or services, or to long-term lease arrangements; or in some cases state governments, unable to relinquish control, have opted for corporatization or commercialization strategies. Reform is driven by the belief that ownership impacts on efficiency and efficiency is perceived to suffer if governments either retain ownership or direct control. As a result a major aim of reform is to either remove or distance governments from day to day port operations. The sale of ports removes government control outright and privatized ports are subject to identical regulatory constraints as any company in the private sector. But corporatization strategies are such that government ownership is retained and ports have been transformed into statutory state owned corporations. Effectiveness of this strategy requires legislation to be such that port corporations are free to operate like their private sector counterparts. To date this has not occurred and some serious impediments are emerging which are embedded in legislation and which, rather than reduce, have indeed, increased government control.  相似文献   
13.
14.
The potential for improving the fuel economy of conventional, gasoline-powered automobiles through optimized application of recent technology advances is analyzed. Results are presented at three levels of technical certainty, ranging from technologies already in use to technologies facing technical constraints (such as emissions control problems) which might inhibit widespread use. A fleet-aggregate, engineering-economic analysis is used to estimate a range of U.S. new car fleet average fuel economy levels achievable given roughly 10 years of lead time. Technology cost estimates are compared to fuel savings in order to determine likely cost-effective levels of fuel economy, which are found to range from 39 miles per gallon to 51 miles per gallon depending on technology certainty level. The corresponding estimated increases in average new car price range from $540 to $790 (1993$). Estimated fuel savings payback times average less than 3 years and the cost of conserved energy averages $0.50 per gallon, indicating that these levels of fuel economy improvement are cost-effective over a vehicle lifetime. A vehicle stock turnover model is used to project the reductions in gasoline consumption and associated emissions that would follow if the estimated fuel economy levels are achieved. Potential trade-offs regarding vehicle performance, safety, and emissions are also discussed.  相似文献   
15.
While various forms of social difference (e.g. gender, age, race/ethnicity, and class) have been engaged in the active school travel (AST) and children’s independent mobility (CIM) literatures, one form has gone largely unconsidered: disability. Disregard for disability within these literatures is troubling, as it leaves children’s experiences of disability associated with independent mobility and school travel unquestioned, which in turn helps to allow their experiences of exclusion to persist. This paper presents a systematic review of the AST and CIM literatures that was undertaken with a view to providing insight into three questions. (1) To what extent is disability considered in the literatures in comparison to other forms of social difference? (2) How is disability engaged? (3) How could disability be approached differently such that experiences of children (and their households) living with disability are better accounted for moving forward (e.g. provided with equitable travel/mobility options)? Following a detailed consideration of the systematic review process, this paper presents figures and tables showing the extent to which disability has been considered in the two literatures in relation to other forms of social difference. To show how transport scholars and others are engaging disability, 29 studies were identified for in-depth, qualitative review. These studies are summarized and then discussed in relation to their geographic focus, the forms of disability they considered, their treatment of children’s perspective and agency, and the disability perspectives they employed. It is suggested that disability and its relationships with other forms of social difference, as well as the largely unquestioned normalcy of children’s disability experiences, warrant further inquiry within the AST and CIM literatures. We propose that drawing upon a critical ableist studies perspective may be useful for any such inquiry due to its focus on ableism and normalcy, as well as its recognition of the complex intersectionality of disability experiences.  相似文献   
16.
In 1997 the Australian government introduced reform measures aimed at improving the efficiency and cost effectiveneess of the Auistralian maritime sector. These measures are part of an ongoing reform programme initiated in the early 1980s; but despite concerted efforts by a succession of governments and the payout of high labour redundancy costs the problems of inefficiency, high costs and low profitability persist. This paper focuses on the structure and mechanism of the policy making processes that have attempted to deal with the problem of making the Australian national flag fleet efficient and competitive. It does so because it is a fundamental tenet of the paper that it is the process of policy making that so frequently—if not invariably—determines policy content and outcomes.  相似文献   
17.
Asian hub/feeder nets: the dynamics of restructuring   总被引:1,自引:0,他引:1  
The emergence of hub/feeder networks in the Singapore-Japan corridor through the 1970s and 1980s reflected not only the rapid growth of containerized cargo in regional Southeast and East Asia but also the exceptional importance of Far East/transPacific and Far East/Europe mainline shipping services in structuring these networks. This paper argues that the mid-1990s is a defining moment in the restructuring of these networks; that the period represents, in fact, a convergence of a number of different though related trends impacting on the regional shipping market. More particularly, continuing high growth rates of containerized cargo have not only spawned new ports but have also increased the proportion of ports handling threshold volumes of containers for which mainline calls, rather than handling thfeeder operations, are justified. Further, the quite dramatic retionalization of already large container shipping lines into mergers and alliances bestows a new level of market power that is able to underwrite major changes in shipping schedules, port rotations and feeder linkages. This paper speculates that these developments are generating, and will continue to generate new, hierarchically organized port/shipping networks in which high order networks will include high efficiency/high cost operations; and lower order networks will include a mix of hub and direct-call ports that will focus on different market segments.  相似文献   
18.
Abstract

Over 90 percent of British Columbia's annual log harvest enters into complex water‐based systems of transportation, storage, and handling. These systems have considerable impacts on a wide range of coastal resources and uses. A number of site‐specific conflicts have arisen between forestry and preexisting or emerging values including fisheries, mariculture, recreational boating, and harbor redevelopment. Specific data on the impacts leading to conflict are often fragmentary. However, concerns about highly valued and fragile areas‐particularly estuariesalong with industrial concerns regarding log losses and handling efficiency, have prompted changes in log handling. These include moves to dryland sorting, log bundling, and a redistribution of forestry activities in estuaries to accommodate other values. Conflict adjustments and responses have in the past been largely ad hoc and attempted in a jurisdictional vacuum concerning control of coastal management. A more inclusive strategy is now slowly emerging, which involves the coordinated participation of federal, provincial, and industrial interests.  相似文献   
19.
坦白讲,实际上这是一篇软文,是一家美国的小规模汽车公司Local Motors的软文。很显然,远在大洋彼岸的我们完全与这个汽车公司所在的市场没有任何关系,也就不可能因为刊登这个软文获得任何商业上的好处。但我还是认为Local Motors的传奇创立者的传奇故事,以及他对待汽车的全新角度将会让你看到一种全新的汽车制造模式,或者说关于汽车制造的思考方式。"我想象的微型工厂里不仅能制造汽车,还会是汽车结束生命的地方。"  相似文献   
20.
汽车设计师盖瑞·麦戈文(GerryMcGovern)的家坐落在无忧无虑的英国乡间,他对自己的这栋现代派宅子相当得意,特地邀我们上门拍摄他的最新杰作、路虎Evoque。车子和宅子本身一样,都停泊在不怎么稳当的斜坡上,两者如面包和果酱一般亲密无间。  相似文献   
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