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991.
As the shipping industry enters the future, an increasing number of technological developments are being introduced into this market. This has led to a significant change in business operations, such as the innovative design of hub and spoke systems, resulting in cargo consolidation and a better use of the ship's capacity. In the light of this new scenario, the authors present a successful application of integer linear programming to support the decision-making process of assigning ships to previously defined voyages — the rosters. The tool used to build the final models was the MS-Excel Solver (Microsoft® Excel 97 SR-2, 1997), a package that enabled the real case studies addressed to be solved. The results of the experiment prompted the authors to favour the assignment of very small fleets, as opposed to the existing high number of ships employed in such real trades, 相似文献
992.
It is a fact that coastal zones in the Mediterranean are becoming progressively more seriously degraded. Instrumental to the phenomenon in Spain is the evident failure of the coastal management that the institutions have pursued for over three decades, both under the old, state-centralized model, and the new organizational model with the political division of land into autonomous regions. This failure can in part be explained not only by the inadequate tools the administration possesses to address the dynamism and complexity of the new economic activities that have sprung up along the coast, but also by incoherent sectoral policies. Finally, there has been no all-encompassing political strategy capable of dealing with coastal communities' demands for development and the need for the protection of ecosystems and their natural resources. All this has resulted not only in a deterioration of the area, but also in the discrediting of actions implemented by the institutions, and their plans and programs being perceived as an obstacle to economic development. 相似文献
993.
The Southeast Atlantic Coastal Ocean Observing System (SEACOOS) collects, manages and disseminates coastal oceanic and atmospheric observation information along the Atlantic coast of the southeastern United States. This article estimates the benefits of SEACOOS information in eleven benefit categories. Following a methodology used in similar studies of other U.S. coastal regions, we evaluate the impacts of conservative changes in economic activity in each benefit category. The annual economic benefit of SEACOOS information is $170 million (2003 $), an estimate that falls between annual benefits of $33 million for the Gulf of Maine region and $381 million for the Gulf of Mexico. 相似文献
994.
S. Cairns C. Newson A. Davis 《Transportation Research Part A: Policy and Practice》2010,44(7):473-494
Across the world, there is increasing interest in managing car traffic. One approach developed for addressing the journey to work is known as ‘workplace travel planning’. This paper primarily reports on 20 case studies of UK employers undertaking travel planning, who had cut commuter driving by an average of 18%. It concludes that considerable behavioural change can be achieved in a variety of contexts – but employers usually need an overall strategy that addresses car parking, in addition to improving alternative travel modes. Moreover, a more comprehensive national strategy is needed, if travel planning is to achieve its potential. 相似文献
995.
Large North American ports are encountering serious management challenges. Surrounding communities, environmental interest groups, and government policy are focusing on protection and enhancement of public coastal amenities. In Vancouver, the federal port management system historically enabled national trade interests to override local and regional objectives at the discretion of port decison makers. In contrast, the Port of Seattle is administered at the local level, and legislation and policy require that local publics are involved in decision‐making. Recently, VPC established itself as the vanguard among Canada's major ports in the advancement of progressive management. Nevertheless, the adoption of new policies would ensure that Vancouver, and Canada's other ports, continue to be responsible leaders in Canadian coastal management. These policies include: federal, municipal, and provincial government representation on the local board of directors; strengthening community involvement; creation of a standing planning advisory committee; subjecting Canadian ports to the federal environmental assessment law; and adoption of explicit land and water use regulations. 相似文献
996.
Abstract This article examines the efforts of the California Coastal Commission to pursue simultaneously goals of environmental quality and affordable housing in the same state‐imposed regulatory program. The authors conclude that the Commission made substantial progress toward realizing both ends. However, the coastal body fell victim to its own successes, and housing was removed from its jurisdiction. As the Coastal Commission exercised its authority, opposition grew in strength and numbers. Key opponents included local government, which lost land‐use regulatory power to the Commission, the building industry, whose relationships with coastal localities were disrupted, and local property owners, whose land was restricted to uses other than the most profitable one. 相似文献
997.
In order to study the influence of wind mixing on the spring variability of the plankton production of the north western Corsican coastal area, a one-dimensional (1D), vertical, coupled hydrodynamic/biological model (ECOHYDROMV) is used. A hydrodynamic 1D model of the water column with a k–l turbulent closure is applied. The biological model comprises six state variables, representing the plankton ecosystem in the spring period: phytoplankton, copepods, nitrate, ammonium, particulate organic matter of phytoplanktonic origin and particulate organic matter of zooplanktonic origin. The system is influenced by turbulence (expressed by the vertical eddy diffusivity), temperature and irradiance. The model takes into account momentum and heat surface fluxes computed from meteorological data in order to simulate a typical spring atmospheric forcing for the considered area. Results show that primary production vertical structure is characterised by a subsurface maximum which deepens with time and is regulated by the opposite gradients of nitrate concentration and irradiance. Surface plankton productivity is mainly controlled by turbulent vertical transport of nutrients into the mixed layer. The short time scale variability of turbulent mixing generated by the wind appears to be responsible for the plurimodal shape of plankton blooms, observed in the considered area. Furthermore, the model is applied to the study of the spring evolution of the plankton communities off the bay of Calvi (Corsica) for the years 1986 and 1988. In order to initiate and validate the model, time series of hydrological, chemical and biological data have been used. The model reproduces accurately the spring evolution of the phytoplankton biomass measured in situ and illustrates that its strong variability in those years was in close relation to the variability of the wind intensity. 相似文献
998.
T. H. S. Li C. J. Huang C. C. Chen 《International Journal of Automotive Technology》2010,11(4):581-592
A novel tracking and almost disturbance decoupling problem of multi-input, multi-output (MIMO) nonlinear systems based on
feedback linearization and a multi-layered feedforward neural network approach has been proposed. The feedback linearization
and neural network controller guarantees exponentially global uniform ultimate bounded stability and almost disturbance decoupling
performance without using any learning or adaptive algorithms. The new approach renders the system to be stable with the almost
disturbance decoupling property at each step when selecting weights to enhance the performance if the proposed sufficient
conditions are maintained. One example, which cannot be solved by the existing approach of the almost disturbance decoupling
problem because it requires the sufficient conditions that the nonlinearities that multiply the disturbances satisfy structural
triangular conditions, is proposed to exploit the fact that the tracking and the almost disturbance decoupling performances
are easily achieved by the proposed approach. In order to demonstrate the practical applicability, a famous half-car active
suspension system is investigated. 相似文献
999.
中国汽车生产商们首先必须了解,哪些是消费者愿意花钱购买的Telematics服务,一味地模仿西方市场,是不够的。 相似文献
1000.
S. S. Merola P. Sementa C. Tornatore 《International Journal of Automotive Technology》2011,12(1):93-101
In this paper, flame front propagation during normal and abnormal combustion was investigated. Cycle-resolved flame emission
imaging was applied in the combustion chamber of a port fuel injection-boosted spark ignition engine. The engine was fueled
with a mixture of 90% iso-octane and 10% n-heptane by volume (Primary Reference Fuel 90: PRF90) and commercial gasoline. The
combustion process was monitored from the flame kernel formation until the exhaust valves opened. Different phenomena associated
with abnormal combustion were analyzed, including the fuel deposition burning. Moreover, the ignition surfaces and end-gas
auto-ignitions were investigated in terms of timing, location and frequency of occurrence. The analysis was performed by considering
different knocking intensities for both the selected fuels. 相似文献