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101.
102.
The Pacific Halibut Catch Sharing Plan formalized the process for allocating halibut between the Alaska commercial and recreational charter sectors. It included a new program intended to allow for “flexibility” through inter-sectoral trading, permitting charter operators to lease commercial halibut pounds to relax client harvest restrictions. Here we evaluate the first two years of lease market activity and participation. Participation from some commercial quota holders in the lease market suggests that the program provided beneficial flexibility; in fact, the number of transfers to the charter sector was greater than transfers within the commercial sector for some quota types. We also identified a high proportion of self-leasers. However, transfers to the charter sector were on average smaller than within-sector commercial transfers, and total poundage leased by the charter sector was low compared with commercial transfers. Usage of leased quota by the recreational charter sector enables the harvest of larger fish or additional fish, and provides flexibility in catch composition on halibut closure days. Finally, the value-per-pound may be higher in the charter sector, as commercial-to-charter transfer prices approached the commercial ex-vessel price.  相似文献   
103.
The concepts of intermodal logistics and distribution networks have made integration of the inland freight distribution system essential for an efficient container seaport system. Inland components, such as dry ports, which exist within the seaport system, have become important in shaping the performance and competitive strategies of container seaports. Owing to the importance of interdependence between dry ports and container seaports, this paper aims to investigate the impact of dry port operations on container seaport competitiveness. It conducted an empirical study in Malaysia through 120 online surveys to key stakeholders of dry ports, including freight forwarders, shippers, seaports, rail operator, shipping lines, and haulers. The data collected were analysed using exploratory factor analysis (EFA). The results from EFA show that Malaysian dry port operations have impacts on seaport competitiveness. These include enhancing seaport performance, increasing service variations for seaports, improving seaport-hinterland proximity, increasing seaport trade volume, and enhancing seaport capacity.  相似文献   
104.
第一眼,你会觉得大众的电动踏板车不过是又一款概念车——只为设计师的幻想而生;但静下心来细究此车,它虽然是今年年初的上海车展上最小的一款概念车,但却有可能成为最重要的一款。在我们和大众中国的设计总监SimonLoasby聊天时,发现他是一个热情奔放的英国人,他对电动踏板车的前景极为乐观。他认为,与其说这是一  相似文献   
105.
The primary cause of most railroad accidents is vehicle entry into railway level crossings despite warning messages. To identify drivers who violate railway level crossing regulations, vehicle license plate recognition can be applied at railway level crossings. The purpose of this paper is to present an effective method for extracting the license plate region from vehicle images taken at railway level crossings. The method proposed in this paper uses the variation in the gray-level values across the image of a license plate. For license plate region extraction, the character region is first recognized by identifying the character width and the difference between the background region and the character region. The license plate region is then extracted by finding the inter-character distance in the plate region. In addition, the license plate type is identified by the difference in the gray-level value between the background region and the character region. The proposed method is effective in solving the current challenges in extracting the license plate region from the damaged frames of license plates issued for domestic use, including new types of license plates. According to the experimental results, the proposed method yields a high extraction rate of 99.5% for vehicle license plates.  相似文献   
106.
The present investigation deals with process analysis of oxy-acetylene flame assisted double pass line heating for varying plate thickness. oxy-acetylene flame as the heat source for multi pass line heating to achieve 3-D bending of plates with varying thicknesses was studied. The oxy-acetylene flame was modeled as the moving heat source in the FEM analysis. The transient thermal histories were predicted taking into account the temperature dependent thermo-mechanical properties. A comparative study between single pass and double pass line heating residual deformation was also carried out. The temperature distribution and residual deformations predicted by the numerical model developed in the present work compared fairly well with those of the experimental ones.  相似文献   
107.
Risk management is an inherent part of supplier selection. While companies are enjoying the benefits of outsourcing, risks brought by this practice should be taken into account in the process of decision making. This paper presents a multiobjective stochastic sequential supplier allocation model to help in supplier selection under uncertainty. Demand for products, capacities at suppliers as well as transportation and other variable costs are the main sources of uncertainty and are modeled using probability distributions. Disruptions are exogenous events and the model provides proactive mitigation strategies against disruptions by assigning backup suppliers who can be used in case of a default at a primary supplier. When there is no disruption, the model’s solution is an optimal supplier order assignment, considering operational risks.  相似文献   
108.
This study aims to investigate how seaport research has been conducted from the methodological perspective. To this end, this study reviews published port literature for the last three decades (1980-2000s). The investigation primarily categorises the literature according to various methodological issues such as research paradigm, research strategy, base-disciplines, research methods and analysis techniques in order to provide meaningful implications on methodological evolution in seaport research for the period. This study suggests methodological bias in port research to a positivistic paradigm, following a quantitative trajectory moving from conceptual to empirical studies. In addition, the increased use of mathematical modelling and advanced statistical analysis methods is clearly observed. The introduction of advanced analytical tools used in other academic disciplines facilitates discussions in particular research area and amplifies the literature in those areas. This paper also suggests research gaps from the methodological perspective and implications for future port research.  相似文献   
109.
Using the WPG03 duty cycle developed from global positioning data collected in Winnipeg, Canada, real world energy demands and costs are modeled. Three types of plug-in hybrid electric vehicles, four temperatures and two charging scenarios are compared to a vehicle with an internal combustion engine. Cold temperatures are shown to greatly affect vehicle operation energy costs, which is an important consideration for cold weather cities such as Winnipeg. The largest energy cost savings are obtained for smaller-battery plug-in hybrids that had the opportunity to charge during the day.  相似文献   
110.
Specifying proximity warning functions for aircraft in managed airspace has received considerable attention. However, similar functions for aircraft operating in unmanaged airspace have received comparatively little analysis despite the fact that these functions are stressed to a greater physical degree, and perhaps more frequently, than in managed airspace. The mid-air collision hazard and its associated risk are re-examined from both an historical and a systematic engineering modelling viewpoint. Historic measures of this transport risk in managed airspace have been based on fatalities normalized by flight hours or flight movements. However some of these data may not be available in unmanaged airspace. Another approach to measurement directs attention to populations at risk where several measures are now well known: collective risk, individual risk and the frequency of occurrence of the hazards that give rise to such risk. A decision support methodology is presented that relates both transport and population-based approaches. A cohesive and consistent set of aspired goals for various stakeholder groups can be set taking into account the different stakeholder needs. A case study is drawn from historic mid-air collision data to illustrate the process. A consistent basis for national-level policy decisions harmonised with proactive engineering design requirements is achieved. The strengths, limitations and implications of this approach for engineering design purposes are discussed.  相似文献   
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