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1.
Doherty  Sean T.  Andrey  Jean C. 《Transportation》1997,24(3):227-251
Despite improvements in road safety over the past several decades, accident rates remain high for young drivers. One accident countermeasure that is expected to improve the safety record of this group is graduated licensing. The philosophy behind this licensing system is that novice drivers, of whom the majority are young, should be restricted to relatively safe driving environments during the initial learning period. Graduated licensing was implemented in the Province of Ontario, Canada in 1994. The objective of this study is to estimate the potential benefits and costs for young drivers associated with two components of the Ontario graduated licensing package: the late-night driving curfew and the high-speed roadway restrictions. Based on accident and travel data for the year 1988, accident-involvement rates per kilometre driven were calculated for different driver groups for various combinations of time of day and roadway speed limit. These rates were then applied to the expected mobility profiles of young drivers affected by graduated licensing. The results of the study support the late-night curfew and suggest that this component of the licensing package should reduce total accident involvements for the affected group by up to 10 percent and fatal accident involvements by up to 24 percent, while reducing their total driving by only four percent. By contrast, the empirical evidence suggest that the high-speed roadway restrictions are likely to increase accident involvements, and thus it is strongly recommended that this component of Ontario's graduated licensing package be changed.  相似文献   
2.
以FRP正弦波形夹心桥面板作为研究对象,得到等效正交各项异性实心板,通过理论分析和数值对比,证明了方法的可行性;采用该法对一实际的FRP正弦波形夹心板桥进行了模态分析。  相似文献   
3.
Globalization, liberalization, competition and spatial interaction are significant factors affecting the transformation of manufacturing industries worldwide. In the transportation and logistics industry, however, cooperation is becoming even more critical than competition in determining firms' efficiency. Cooperation has always characterized the liner sector in which strategic alliances, mergers and acquisitions have generated twin effects: notable increases in ship size and falls in freight rates. Meanwhile, the stevedoring industry is undergoing privatization-driven consolidation and the emergence of global pure terminal operators. This article focuses on vertical integration between global carriers and terminal operators. We address the following key current issues:
  • dedicated terminals as a strategy for cutting costs and controlling integrated transport chains;
  • the struggle for supply chain control, involving global carriers versus global terminal operators, driven by financial power and technical and managerial capability.


We close analysing one of the core problems of the market, namely the evolving role of the dedicated terminals. For the pure stevedores they represent an opportunity to secure a cargo, while in the hands of the liners they enable cost stability and the possibility to put pressure on pure terminal operators.  相似文献   
4.
This note investigates the important attributes relating to the crowding effects at the Mass Transit Railway (MTR) stations in Hong Kong. Data was collected at two sets of three MTR stations to study the responses of the passengers due to the discomfort at crowded vehicles and platforms. Stated preference surveys were used to study the effects of passenger discomfort measures.  相似文献   
5.
This article is in three parts. The first covers the historical development of qualifying associations. The second covers the particular role of maritime institutions that include The Royal Institution of Naval Architects, The Institute of Marine Engineering Science and Technology and The Nautical Institute. The third and final section considers the future for maritime professional associations in the context of international shipping.  相似文献   
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The nature of the global economy is one of dynamic change. Shipping is a service industry with its demand related to changes in international trade levels and patterns. As a consequence shipping is subject to sometimes unpredictable swings in demand so that the operator is required to make strategic planning decisions while navigating through boom or bust environments. While boom economies generate rising freight rates which are welcomed and encourage investment, ship operators may also have to face falling freight demand and declining freight rates that may have significant impact on profitability, often falling to uneconomic levels for extended periods. In such a period of uncertainty and declining profitability management will make operational decisions to reduce costs. However, shipping lines operate in a market environment so any decisions made to rationalize the trade may have significant long-term competitive implications. For example, traditional micro economic theory might suggest that the prudent strategy to adopt would be to close down the operation and reopen when the market conditions improve. In a world of certainty or when costs of taking this action are zero, this would be a valid strategy. However, because of fear of competitors taking up a line's market share if the shipping company exits, even temporarily, this strategy cannot be valued simply in terms of shut-down and start-up costs. A further consideration is the fact that standard capital budgeting techniques, such as Net Present Value (NPV), cannot incorporate the flexibility to respond to new information and strategic responses explicitly into their investment analysis. This paper will demonstrate the use of Real Option Analysis (ROA) to provide guidelines for decisions about closing operations in adverse market conditions.  相似文献   
9.
The Agulhas Current with its retroflection and attendant eddy-shedding is the cause of some of the greatest mesoscale variability in the ocean. This paper considers the area to the south and east of Madagascar, which provides some of the source waters of the Agulhas Current, and examines the propagating sea surface height signals in altimetry and output from a numerical model, OCCAM. Both show bands of variability along the axis of the East Madagascar Current (EMC) and along a zonal band near 25°S. Sequences of images plus associated temperature data suggest that a number of westward-propagating eddies are present in this zonal band. The paper then focuses on the region to the south of the island, where ocean colour and infra-red imagery are evocative of an East Madagascar Retroflection. The synthesis of data analysed in this paper, however, shows that remotely observed features in this area can be explained by anticyclonic eddies moving westward through the region, and this explanation is consistent with numerical model output and the trajectories of drifting buoys.  相似文献   
10.
Macrobenthic surveys are an expensive, slow and labour intensive means to establish the health of benthic communities. Sediment profile imagery (SPI) is a means of rapid reconnaissance for monitoring large areas of the benthos. SPI has often been used to monitor gross anthropogenic disturbance. The aim of this study is to determine if SPI can be used as a tool to reliably map change in communities along natural estuarine gradients. Macrobenthic sampling was carried out at five stations along an established estuarine gradient. This faunal data was analysed using standard multivariate techniques and to ground truth a concurrent SPI survey. Faunal analysis showed that habitat quality in Inner Galway Bay was generally good, with some localised disturbance from the River Corrib and the sewage out flow exterior to the city dock. Four distinct groups were identified with a degree of overlap occurring between stations 3 and 4. While existing SPI indices mapped habitat quality in the same manner as the faunal data for end member stations, the level of distinction between the habitats of an intermediate staging was found to be poor. This lack of distinction amongst the stage 2 and 3 stations was overcome by developing a tailored index, the Galway Bay index of habitat quality (GBHQ). This index was derived from the 5 observed variables in the SPI data that were determined to best match the faunal distribution by permutative mantel testing. The 5 observed variables from the SPI data were the depth of the apparent redox potential discontinuity (aRPD), the depth of penetration by the prism, and the presence/absence of infauna, surface faecal pellet layer and biogenic mounding. The GBHQ was able to distinguish between the 5 stations to a greater extent than previously described indices, showing clearly the separate groupings defined by the faunal data. The index was tested on a follow up SPI survey and shown to be applicable in mapping a broader range of habitats in Galway Bay. Indices generated for localised mapping of estuarine gradients should be derived from observed features and be ground truthed using faunal data. Some aspects of the GBHQ should be generally applicable to fine grained boreal estuarine sediments (aRPD/penetration), while others may be of limited utility in other locations depending on the digging characteristics of the particular SPI camera, and local factors influencing the persistence of biogenic features in the profile. This derivation technique provides a simple way to optimise SPI to particular studies and localities.  相似文献   
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