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961.
In our critique for the Buses White Paper, we argued that ‘competition for licences’ could achieve most of the benefits of competition without the major disadvantages of ‘competition on the road’. In response to the comments of Beesley and Glaister, we explain how comprehensive franchising of good and bad routes alike would encourage effective competition, whilst providing conditions for the transparent continuation of cross‐subsidy where that was the choice of the local authority in question. We correct their misrepresentation of our arguments on the desirability of cross‐subsidy and on the case for minibuses, and explain why we believe that such cost savings as are achieved will be mainly at the expense of staff or customer service. Finally, we restate the case for believing that a unified planned timetable will provide a better service for a given level of resources than will uncoordinated competitive services. 相似文献
962.
Over the last fifty years ground transportation management (GTM) has slowly evolved into a major function at most larger airports. However, during this time there has been relatively little written discussing the idea, organization structures or duties included within this functional activity. This paper reviews and updates the limited, earlier research. This study replicates initial work done in 1989 and thus provides a short longitudinal view of the airport GTM function. The final results demonstrate the current position of GTM and suggest trends for the future. 相似文献
963.
Substantial investment has been made at national and European level in transport infrastructure over the past 50 years and is likely to continue in the future. The need to appraise transport projects in economic and social terms has developed alongside this in both scope and complexity. The state-of-the-art in the economic appraisal of transport projects is reviewed, progress is assessed and future challenges are identified. The review addresses the general framework, treatment of major impacts, presentation of outputs and issues such as uncertainty. It draws on national practice in Western European countries, which varies substantially reflecting a range of cultural and economic differences. Some points of commonality exist and the principle of monetizing direct transport impacts is generally accepted. Progress has been made towards the measurement of environmental impacts, but the assessment of the wider impacts remains under-developed. Increased sophistication and complexity has brought increasing data and presentation requirements, where computerized decision support methods have potential. Many challenges exist for the future of appraisal and the review is concluded with a discussion of some key issues. At the heart of these is the continuing debate over the relative roles of national and European government in decision-making and resource allocation. 相似文献
964.
Edgardo D. Gomez Helen T. Yap Patrick C. Cabaitan Romeo M. Dizon 《Coastal management》2013,41(5):556-574
The scleractinian coral Montipora digitata (Acroporidae) is a common reef flat species that thrives under high levels of light and water turbulence, and propagates successfully by natural fragmentation. It was used for transplantation experiments in an attempt to restore a degraded lagoon environment in the northwestern Philippines. Branches about 5 cm high from a natural population in the lagoon were transplanted to dead coral outcrops or knolls in two locations (Binlab and Malilnep-Ac) with different environmental characteristics. Growth and survival were significantly better at Malilnep Ac, which resembled the natural habitat of the species more closely. Environmental conditions at this site also favored the establishment of a greater diversity of species around the coral transplants. There was no difference in performance between transplants on vertical and horizontal surfaces, and the transplants showed limited differences due to density within the experimental range. Significant survival of detached, transplanted colonies or fragments thereof around the bases of the experimental bommies at the more successful site was an additional positive outcome. Water motion showed significant effects on survival and growth, possibly enhancing the suitability of the more successful site for transplantation. These results demonstrate the potential of coral transplantation to initiate the establishment of natural communities in degraded reef areas, a concern for coastal managers in developing countries. 相似文献
965.
J. Foster-Smith A. C. Birchenough CEFAS S. M. Evans J. Prince 《Coastal management》2013,41(2-3):181-194
There are concerns that Cable Beach, which is of outstanding natural beauty and a major tourist attraction for Broome and the Kimberley region of northwest Australia, is suffering damage from recreational use, particularly that caused by off-road vehicles. To assess current levels of human impact on the shore and its fauna, the southern-most kilometer of the Beach, covering an area to which vehicles had access and an adjacent area closed to vehicles, was surveyed for human usage and shore crab abundance. Human usage over the recording period was high in the area with high vehicular access. The amount of litter, although considerable, was well below that recorded in some other tourist destinations elsewhere in the world. Burrows of both the ghost crabs Ocypode spp, and the sand bubbler, Scopimera inflata, were less numerous in areas of high vehicle use than those of low use. Both species may be valuable in monitoring human impacts on Cable Beach. 相似文献
966.
Inseok Park Seungwoo Hong Myoungho Sunwoo 《International Journal of Automotive Technology》2017,18(4):579-587
This paper presents a model-based gain scheduling algorithm of a PI-based EGR controller for light-duty diesel engines. In order to capture nonlinear characteristic of the EGR system, we have proposed a new scheduling variable to illustrate the static-gain of the plant model as a linear function. The proposed scheduling variable is composed of the air-tofuel ratio of the exhaust gas and the pressure ratio between the exhaust and intake manifolds. Using the scheduling variable, a static-gain model achieved 0.94 of the R-squared value with 810 of steady-state measurements which include key engine operating conditions. Based on the model of the static-gain parameter, the gains of the PI controller are decided by Skogestad internal model control (SIMC) tuning rule in real-time. Through various scenarios of engine experiments, the proposed gain scheduling algorithm represented that the PI gains were successfully adapted according to the changes of the engine operating conditions. 相似文献
967.
Anthony T.H. Chin Joyce M.W. Low 《Transportation Research Part D: Transport and Environment》2010,15(8):483-488
Atmospheric and water pollution are two main sources of negative environmental externalities generated by shipping. This study recognizes the negative externalities in the production of port services in East Asia by explicitly incorporating environmental impacts of shipping. Programming techniques are used to analyze 156 Origin–Destination pairs between 13 major East Asian ports, to derive the externality-augmented measures of port productivity and efficiency at the waterside. The results suggest that the inclusion of externality mitigation strategies can exert a considerable influence on efficiency performance. 相似文献
968.
This paper deals with the lane assignment problem in the Automated Highway Systems (AHS). The purpose of lane assignment strategies
is to increase throughput on multi-lane highways with many entry and exit points, based on the itineraries of vehicles using
the highway (point of entry, time of entry and exit point) and the effects of maneuvers. Using partitioned lane assignment
strategies, the lane assignment problem is formulated as an optimization problem to find the proper positions of partitions.
Then the optimal problem is solved using a Genetic Algorithm (GA). The proposed algorithm has been validated by comparing
its solution with that of an all-cases algorithm for a simple case. Moreover, a traffic simulator with a realistic car-following
model as well as lane change logic has been developed. The simulation results show the efficiency of the proposed genetic
algorithm, compared with random assignment algorithms. 相似文献
969.
The relationship between financial system, law framework or economic growth has attracted considerable attention for years. However, there are some questions still remaining unanswered: between tangible assets protection and intellectual property protection, which is more important? Between external financing and property rights protection, which does play a greater role for the economic development? According to the dynamic stochastic general equilibrium(DSGE) model with non-free market factors, we study the effectiveness of property protection and external financing, and try to answer these questions. The model fits the data well, and we find:(1) protection of intellectual property plays a more important role than that of tangible asset, in the promotion of economy;(2) relaxation of financial constraints on corporate is more effective in the short run, while the protection of intellectual property is more effectual in the long term. 相似文献
970.
An assessment of the rationale for the vertical disintegration of ship management suggests that there might be compelling economic benefits for the separation of ownership from management. In this context, as a means for developing effective marketing strategies, it is important for ship managers to know the criteria used by current and prospective clients for ship manager selection and evaluation. The aim of this paper is to empirically identify the dimensions for ship manager selection and performance evaluation and their relative importance and to discuss the implications for marketing emanating from such an assessment. The methodology adopted includes the collection of secondary and primary data, both from ship managers and their clients, using interviews and a mail survey. The results indicate the prevailing importance of certain dimensions in selection (e.g. technical ability, reputation, competency) and evaluation (responsiveness, trustworthiness, technical ability), whereas it also found that price alone is not perceived to be as important in ship manager selection. It is concluded that placing emphasis on such dimensions in the formulation of a marketing strategy will contribute towards the attraction and retention of clients, whereas cost-cutting measures to allow price reduction, as well as advertising, will be ineffective over the long term. 相似文献