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791.
792.
G. Levikov 《Maritime Policy and Management》1988,15(3):247-254
In light of the Reveiw Conference on the UN Code of Conduct for Liner Conferences to be in November 1988, this paper highlights some of the Major problems impinging upon the universal acceptability of the Code. These include the reservation (known as the Brussels Package) by EC and certain other OECD countries that discriminates aganist developing and Socialist countries; reservations of a controversial nature with regard to the establishment of joint shipping lines established on the basis of intergovernmental bilateral agreement; and the question of compctition by non-conference lines that diminishes the share of cargo available to National Lines by virtue of the Code. 相似文献
793.
This paper undertakes a comparative analysis of the stock market perception of risk in US listed water transportation companies and seven other main sectors, air transportation; rail transportation; trucks; electricity; gas; petroleum refining; and real estate over the period July 1984-June 1995. This is done by employing the Capital Asset Pricing Model (CAPM) to model the stock returns of each industry and hence compare their betas (systematic risk). Multiequation Regression Models are used for estimation. The findings suggest that the water transportation industry exhibits significantly lower market risk than the average stock and the rail transportation industry, significantly higher systematic risk than the real estate industry, while its systematic risk is insignificantly different from the rest of the industries. These results are useful to investors basing their decisions on relative market exposures to risk in different industries. 相似文献
794.
G. F. Mazepova 《Journal of Marine Systems》1998,15(1-4)
This describes a study of the pelagic zone of Lake Baikal with particular reference to copepods. In addition the cycling of matter and energy in lacustrine basins is described. 相似文献
795.
An experimental technique for exploring the sensitivity of transportation plan evaluations to forecasting and community value uncertainties is described. Three kinds of uncertainty — goal-achievement impacts, costs, and goal-weights — are included. Within a cost-effectiveness evaluation framework, an on-line capability for interactively and iteratively testing plan comparisons is outlined. A series of user-oriented computer instructions is developed to test plan comparison outcomes according to a wide variety of user-selected changes in impact forecasts, goal weights, and cost forecasts. A sample, hypothetical application of the technique is described. The technique is currently under further development by the San Diego Region Comprehensive Planning Organization. 相似文献
796.
E.J Murphy P.W Boyd R.J.G Leakey A Atkinson E.S Edwards C Robinson J Priddle S.J Bury D.B Robins P.H Burkill G Savidge N.J.P Owens D Turner 《Journal of Marine Systems》1998,17(1-4)
Most analyses of marine microbial systems in the seasonally ice covered areas of the Southern Ocean have been based on data from the major embayment areas of the Ross and Weddell Seas. In this study data were collected at stations covering a range of regimes from full ice cover through to open water in the Bellingshausen Sea. A major feature of the production system was a rapid retreat of the ice-edge, which uncoupled the marginal ice zone from a phytoplankton bloom which remained associated with a frontal system. This bloom was maintained, and probably initiated, in an unusual environment generated by the interaction between the marginal ice zone and the front. Size-based analyses of the microbial system were derived for ice-covered, recently ice-covered and open water sites. Estimates of standing stocks and key rate processes were combined to produce a single food web network for each station. The under-ice system was one of low production and low recycling but apparently high retention. As the ice retreated the microbial systems to the north began to develop, but these were constrained by grazing pressure. The bloom in the area appeared to be sustained even though estimated losses were far higher than production, although the high sedimentation losses expected were not observed. The carbon flow networks are discussed in relation to the environmental changes and the interaction of the marginal ice zone and the frontal system appears crucial to the phytoplankton. Microzooplankton grazing is implicated as a major controlling factor. The local microbial dynamics are strongly influenced by material which was produced at an earlier time and somewhere else in the Southern Ocean. 相似文献
797.
798.
799.
A. G. Thompson Visiting Senior Research Fellow 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1977,6(1):37-40
The yaw rate response for a two-degree-of-freedom car model requires a family of curves for different degrees of oversteer or understeer. By use of non-dimensional co-ordinates this family is reduced to one single curve. The ordinate ρ is the ratio of yaw rate response to that of a neutral steering car at the same speed and is less than 1 for understeer and greater than 1 for oversteer. Since ρ is also the ratio of the side-slip angle response it is hence, a unique measure of the steady-state steering characteristics. 相似文献
800.
Solution of the Multiple Wheel and Rail Contact Dynamic Problem 总被引:1,自引:0,他引:1
G. Sauvage J.-P. Pascal 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1990,19(5):257-272
An unconventional method for calculating the forces developing in the wheel and rail contact patches of a railway vehicle has been implemented at the New Technology Laboratory of INRETS. It takes into account the elastic deformations of the materials in the Hertzian elliptical contact areas; the possibility of having simultaneously several contact patches on each wheel, is introduced in the simulation of the dynamic phenomena.
The theory is applied for a high speed bogie running on a perfectly straight track. 相似文献
The theory is applied for a high speed bogie running on a perfectly straight track. 相似文献