The development of ro/ro services in Marseilles: Part 1

This paper discusses the growth of ro-ro services operating to and from Marseilles and the adaption of port structures to facilitate this growth. The concluding section of Part 1 of the paper analyses throughput performance.     

A combined science and management framework for developing regional monitoring objectives

Abstract

Designing environmental monitoring programs to deal with widespread, subtle, and/or cumulative impacts on a regional basis is challenging. It requires a shift away from focusing primarily on individual point sources to a more regional perspective. It also necessitates involving scientists and managers together in a cooperative effort to establish priorities and articulate clear objectives. In our view, this objective‐setting task is neither a strictly scientific nor a strictly management activity. It depends on effective communication between scientists and managers but is confounded by differing perspectives, value systems, and behaviors. We present a conceptual framework to assist managers and scientists in this process. This is intended to structure such communication by helping to create a context that permits fruitful give‐and‐take between the two groups. We then describe a six‐part model for specifying the key elements of regional monitoring objectives.     

Selatm — a GIS based program for evaluating the safety benefits of local area traffic management schemes

Particular safety problems relate to traffic on local streets. Local Area Traffic Management (LATM) schemes are often implemented with the objective of counteracting these safety problems. One analytical difficulty in appraising the effectiveness of LATM in dealing with safety problems has been the ‘footloose’ nature of accident locations in a local street network. Seldom are there distinct ‘blackspot’ locations. An area‐wide approach is needed and the interaction between the system and arterial road network must be considered. The paper describes the development of a Safety Evaluation Method for Local Area Traffic Management (termed SELATM). It is a GIS‐based program for analysing accident patterns over time and the evaluation of the safety benefits of LATM schemes. The evaluation is perform at different network levels for various accident variables. The thrust of the program involved the integration of network data with data on accidents and the installed devices to generate summary accident statistics for the various network levels allowing for before and after comparison with a control area. This program as developed is applied to a LATM scheme at Enfield, a suburb in metropolitan Adelaide.     

Computer modeling and validations of steel gear heat treatment processes using commercial software DANTE

The heat treatment process of a gear made of AISI 9310 carburized steel is modeled using the commercial heat treatment simulation software DANTE. Both carburization and quenching processes affect the residual stress distribution and distortion of heat-treated parts, which are important to service quality and fatigue life. DANTE/VCARB is used to design the boost/diffuse schedule of a vacuum carburization process. Oil quenching is modeled following the vacuum carburization process. Thermal gradient and phase transformation are two main sources of distortion and residual stresses in quenched parts. The relation of the carbon distribution, thermal gradient, and phase transformations during quenching is studied through the gear modeling example. Because of geometry, the residual stress distribution after quenching is non-uniform along the gear surface. In general, the root fillet has higher residual compression than either the root or tooth face locations after traditional oil quenching of carburized gears. The predicted residual stresses from the oil quenching model are imported into a single tooth fatigue bending model. The gear stresses under bending load indicate the possible cracking locations during the bending fatigue test. The importance of heat treatment residual stresses during gear design is pointed out, and it is commonly ignored in the gear design and manufacturing industry.     

The effects of regulatory reform on the US inter‐city bus industry

Transport regulation in the USA has undergone radical reforms over the past decade. This paper looks specifically at the comparatively neglected topic of the 1982 Bus Regulatory Reform Act which liberalized the regulations governing US inter‐city bus transport.

The Act represented a significant reform of the 1935 legislation which had formed the basis of regulation for nearly fifty years. It liberalized entry and fare controls and gave power to the Interstate Commerce Commission to override State decisions. The paper details the changes, examines their rationale and assesses the impact they have exerted on the US inter‐urban bus industry. The general conclusion is that overall the Act has been beneficial in improving the economic efficiency of carriers although some minor reservations must be retained regarding its adverse effects on smaller towns and rural areas.     

British location rents: an interpretation of the dual transportation problem for commodity flows

The transportation problem is solved for a number of commodity flow matrices for Britain for 1972. The commodities were selected because of the likelihood of the transportation problem producing a relatively good fit. Commodities were also chosen when it was thought that accessibility was a key location factor. The rationalisation of the interpretation of the dual values as shadow prices and location rents is outlined and, after discussing the merits of alternative means of analysing and presenting the dual values, the distribution of these values are compared with the actual location of industry. Some difficulties and further implications of the approach are suggested.     

Maritime legislation: new areas for safety of life at sea

This study reveals areas where IMO regulations of safety of life at sea can be improved upon. After examination of 5389 mortality and 3559 accident cases of UK seamen and 6878 fatalities of worldwide seamen, it finds fatalities due to personal accidents on board ship constitute ～90% of all mortality cases. Therefore, prevention of personal accidents should be given a higher priority. It reveals also that accidents involving coastal (domestic) ferries were another concern in the safety of life in shipping, e.g. in 1996 alone more than 2562 fatalities occurred in this sector. As a case study, the nationalities of 364 deceased seamen in bulk carrier disasters (1990–1998) are identified. Fatalities to British and worldwide seamen are based on the data obtained from various sources. However, fatalities to seamen working on board open registry ships are the best estimation, based on the information available to the authors.     

Price and frequency competition in freight transportation

This paper develops a simple analytical model of price and frequency competition among freight carriers. In the model, the full price faced by a shipper (a goods producer) includes the actual shipping price plus an inventory holding cost, which is inversely proportional to the frequency of shipments offered by the freight carrier. Taking brand loyalty on the part of shippers into account, competing freight carriers maximize profit by setting prices, frequencies and vehicle carrying capacities. Assuming tractable functional forms, long- and short-run comparative-static results are derived to show how the choice variables are affected by the model’s parameters. The paper also provides an efficiency analysis, comparing the equilibrium to the social optimum, and it attempts to explain the phenomenon of excess capacity in the freight industry.     

响应面法模拟轴肩和搅拌针形状对铝合金搅拌摩擦的影响(英文)

The present paper discusses the modeling of tool geometry effects on the friction stir aluminum welds using response surface methodology. The friction stir welding tools were designed with different shoulder and tool probe geometries based on a design matrix. The matrix for the tool designing was made for three types of tools, based on three types of probes, with three levels each for defining the shoulder surface type and probe profile geometries. Then, the effects of tool shoulder and probe geometries on friction stirred aluminum welds were experimentally investigated with respect to weld strength, weld cross section area, grain size of weld and grain size of thermo-mechanically affected zone. These effects were modeled using multiple and response surface regression analysis. The response surface regression modeling were found to be appropriate for defining the friction stir weldment characteristics.