The U.S.S.R.: Ocean Use and Ocean Law

This paper is an attempt to illustrate the stance of the Soviet Union in the law of the sea debate in the light of Soviet ocean activities. The paper has two sections. First, it examines the range of Soviet ocean activities. The considerable extent of Soviet ocean use underscores the importance which the Soviet Union places on the law of the sea debate and its consequent active participation in the process of international negotiation. Second, the paper considers the published record of the Soviet Union in the United Nations seabed debate. In seven years of debate the United Nations General Assembly and the Ad Hoc and permanent Seabed Commities and sub-Commities have generated a considerable body of documantation reflecting the public policy of over one hundred States concerning the law of the sea. Soviet expressions of opinion alone cover more than five hundred pages of documentation. Specific Soviet positions can be considered within two ganeral preferences: the protection of traditional freedoms of the high seas and opposition to ocean control by either coastal States or by an independent international ocean authority. The paper shows how these preferences and the specific Soviet negotiating positions defend and promote the maritime interests of the Soviet Union.     

A Study in Port Planning: The Example of Mina Zayed

The correct number of berths that a port should provide is solved by a model which minimizes the total port usage cost in terms of the costs of berth provision and the costs accruing to ships from time spent in the port. This model is then applied to Mina Zayed in the Arabian Gulf as an aid to future planning, and from different sets of cargo forecasts an optimal stategy is derived using a game-theoretic approach.     

The treatment of capital costs of vehicles in evaluating road schemes

There are two ways in which new road schemes may influence capital expenditure on vehicles. Firstly, by improving utilisation of existing vehicles, the size of fleet needed to perform a given volume of work may be reduced. This will clearly reduce the amount of capital tied up in motor vehicles at any point in time, and to the extent that vehicle life is determined by age rather than mileage run, will also yield savings in terms of investment in new vehicles. Secondly, by generating additional road traffic, road schemes may lead to an increase in the stock of vehicles in use.This paper argues that the current treatment of vehicle depreciation and interest charges in U.K. cost data fails to allow correctly for either of these items. Errors of logic occur in the way in which the capital stock of vehicles is valued, and in the fact that certain overheads are ignored even when fleet size changes. Moreover, the empirical evidence supporting the current partitioning of depreciation into overhead and running cost components, and the assumption of constant hours in service after an increase in journey speed seems of doubtful validity.An alternative method of calculating vehicle capital costs, based on the concept of annual capital charge, and making explicit the assumptions with respect to vehicle utilisation, is advocated, and the sensitivity of results to the view taken of the latter is demonstrated by means of specimen calculations.     

Efficiency of the public and private bus transport sectors in Sri Lanka

The public and private bus sectors are in direct competition in most bus routes in Sri Lanka. Consequently, Sri Lanka is an ideal location to study their relative efficiencies. Five dimensions of transit performance are analyzed for comparing the relative efficiencies of the two sectors: cost efficiency, labour efficiency, input efficiency, revenue generation and safety. Productivity ratios are utilized for measuring the dimensions of transit performance. The productivity ratios for cost efficiency, labour efficiency in terms of total staff, input efficiency, revenue generation and safety in terms of accidents per bus showed the private bus transport sector to be more efficient than the public bus transport sector.     

Nonlinear Attitude Dynamics of Twin Cycle with Feedback Control

The nonlinear attitude dynamics of a twin cycle under output feedback control is studied through bifurcation analysis. Two cases are considered. One assumes no slip and the other assumes small slip. The double zero bifurcation is found to occur in both cases but with different bifurcation sets. Among them heteroclinic orbits are found in both cases and a limit cycle in the second case. The region of feedback gains for stability is obtained. Large negative feedback gains are found necessary to assure stability of the twin cycle. Finally, the tire effect is studied and it causes the distortion of the bifurcation sets.     

Vehicle Response to Stochastic Roadways

Dynamic response calculations for vehicles traversing irregular surfaces are usually accomplished using frequency domain methods involving spectral densities and transfer functions. Here an alternative procedure is developed which allows direct computation of mean square values and correlations of system variables for both transient and steady-state conditions. The method is based upon the differential equation for the covariance matrix which is directly related to the state equations for the vehicle. Multiple white noise inputs can be incorporated as well as inputs at two wheels which follow the same track at a distance from one another..The method is suitable for computer implementation without the complex algebra associated with finding all necessary transfer functions and the necessity of evaluating integrals in order to find mean square values using the conventional approach. As an illustration, a simple vehicle model is worked out completely and the variation of pitch and heave motion as a function of vehicle speed is plotted.