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641.
642.
Trevor D. Heaver 《Maritime Policy and Management》1983,10(3):199-206
In this paper the author reviews recent developments in Canadian government policy with regard to national-flag shipping. In response to criticism from various marine interest groups that successive governments have done little to encourage the development of national-flag shipping, federal administrations have taken a more active part in the debate. This has been manifest in several reports produced under the auspices of Transport Canada, which discuss the desirability of using selective tax or fiscal incentives to promote investment in Canadian shipping. The author outlines the arguments for expanding national-flag shipping, relating these to the greater question of what effect these proposed financial measures might have on the use of capital and other resources. He concludes that selective preferential taxation may be justified by the repatriation of shipping activities now offshore and avoidance of further shifts of manpower and capital offshore. 相似文献
643.
John R. Siddorn J. Icarus Allen Jerry C. Blackford Francis J. Gilbert Jason T. Holt Martin W. Holt Jeff P. Osborne Roger Proctor David K. Mills 《Journal of Marine Systems》2007,65(1-4):417
This paper outlines an approach to complex spatio-temporal marine ecosystem modelling as applied to the North Western European Continental Shelf. The model presented here combines an eddy-permitting (approximately 6 km horizontal resolution) baroclinic model, the Proudman Oceanographic Laboratory Coastal Ocean Modelling System (POLCOMS), with the European Regional Seas Ecosystem Model (ERSEM). This has been run within an operational framework using operationally available high resolution atmospheric and lateral boundary forcing, allowing hindcast and near-real time nowcast simulations to be performed. The modelled surface temperature and chlorophyll distributions are presented, and interannual variations discussed. Validation of both the physical and ecosystem submodels show the system to be effective, whilst highlighting areas where improvements in the system can be made. Distinct regional differences in predictive skill are shown. The system presented is ready for operational implementation to provide products and services for use both scientifically and in coastal zone and shelf seas management activities. A programme of work to update the system is already in place. 相似文献
644.
The motions of an infinitely long, two-dimensional runway subjected to the dynamic moving load imposed by an airplane taking
off are investigated. The runway is assumed to be floating in an inviscid fluid and is initially at equilibrium before the
plane takes off. The deformation of the runway resulting from the take-off is wave-like and moves in the same direction as
the plane. The maximum drag occurs when the plane catches up with the first wave. Three different runway configurations were
considered: a baseline and ones which were ten and one hundred times more flexible than the baseline. For these runways, the
added drag to the aircraft was very small, ranging from 1% for the stiffest to 10% for the most flexible runway. 相似文献
645.
646.
Floriano C. M. Pires Luis F. Assis Cassiano M. Souza 《Maritime Policy and Management》2005,32(3):209-226
The Brazilian ship financing system has some unique features. The funds made available to finance the construction and acquisition of ships are sourced from a tax on import and cabotage freight, payable by the shippers. For Brazilian flagged ships, a portion of the tax generated can be used for the payment of loan instalments. This paper analyses the impact of the tax on the economy as a whole, and discusses the distribution of the tax burden between the shipowner and the shipper, taking into account the maritime transport demand elasticities in Brazil. The paper also analyses the effectiveness of the financing system in reducing the capital cost to shipowner, and the distortion effects produced by the utilization of the tax in loan repayments. The conclusion is that there are important distortions that may threaten the recovery of the maritime industry in Brazil. 相似文献
647.
To be beneficial to management, productivity concepts must be translated into terms that are meaningful to managers at all levels of the organization. Productivity per se is not nearly as important to these people as service quality and financial performance, especially since measured productivity can improve while profits or service levels decline. Productivity must, therefore, be related to an integrated set of performance measures that reflect costs, revenues, trip times and reliability, equipment availability and other matters of continuing concern to transportation companies. Planning and control are critical components of any program to improve productivity. The techniques required to measure and understand productivity are precisely those used in planning and in developing control systems. Furthermore, productivity is conceptually very close to cost analysis, which is a major focus of planning and control. Any transportation company has access to the data needed to develop a vast array of performance measures, including many productivity measures. This paper will illustrate the way that railroads can integrate productivity concepts within more global performance measurement systems. Specific attention will be given to terminal control systems, costing systems for origin-to-destination movements and life-cycle costing techniques for track maintenance planning. 相似文献
648.
The influence of workplace environment on lung function of shopkeepers working near National Highway in Jalgaon: A note 总被引:1,自引:0,他引:1
S.T. Ingle N.D. Wagh B.G. Pachpande V.S. Patel S.B. Attarde 《Transportation Research Part D: Transport and Environment》2005,10(6):476-482
The inferior ambient air quality was observed near highway passing through Jalgaon urban center. Among the pollutants critical level of particulates are observed at the roadside during May 2003 to April 2004. The shopkeepers working at the highway sides are at high risk of exposure to the air pollution caused by heavy highway traffic. The lung function test of the shopkeepers shows significant decrease in forced vital capacity, forced expiratory volume in one second and peak expiratory flow rate. The regular periodic health checkup and use of nose mask will protect the health of shopkeepers working near National Highway passing through Jalgaon urban center. 相似文献
649.
650.
Electronically Controllable Vehicle Suspensions 总被引:3,自引:0,他引:3
D. Karnopp G. Heess 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1991,20(3):207-217
The basic functions which suspensions must perform are described and categories of controllable suspensions based on the required amount of control power are defined. The kinds of devices which can be used in controllable suspensions are discussed as well as several basic control philosophies. Finally, fundamental theoretical and practical limitations in suspension performance are indicated. 相似文献