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181.
This paper analyses foreign direct investments (FDI) in Asia by the Norwegian maritime industry. It focuses on three topics: (1) Why do Norwegian maritime companies invest abroad? (2) What are the effects of maritime foreign direct investments on the Norwegian maritime milieu? (3) What are the effects of these investments on the host country? By analysing specific Norwegian maritime companies, it was found that the FDIs have partly been induced by the instability of the Norwegian policy towards this sector. Several firms also point at the importance of being closer to the Asian market as a significant reason for FDI, and the Norwegian ship equipment industry tends to 'follow' the shipping companies abroad. The domestic effects of FDI are uncertain, and are likely to depend on the motivation behind the investments. Finally, using Singapore as an example, it is argued that the host country effects of FDI tend to be positive. 相似文献
182.
Hans B. Pacejka 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1973,2(3):161-172
An approximate method is presented which produces a handling diagram useful for the study of steady-state turning behaviour at different values of steer angle, path radius and speed In three successive parts the steady state response of simple and more elaborate vehicle models and the stability of the resulting motion are discussed. 相似文献
183.
In Europe, ports are confronted with a closer integration in the maritime and shipping industries. The co-operation agreements can take several forms such as alliances and mergers among shipping lines, conferences, involvement of shipping companies in terminal management, and extending interests in inland transport of shipping companies. In this paper we give a brief overview of these different types of agreement and we examine the consequences of this evolution of the market structures in which ports and shipping companies have to operate. More specifically, attention goes to the competitive position of the port in this new environment. It is clear that the role of the port and the port authorities has to be redefined to guarantee that it remains a fully fledged player in this fast evolving integrated market. 相似文献
184.
Huizhao Tu Hao Li Hans van Lint Henk van Zuylen 《Transportation Research Part A: Policy and Practice》2012,46(10):1528-1540
Travel time reliability is considered to be one of the key indicators for the performance of transport systems and is measured in various ways. This paper synthesizes both reliability concepts: traffic breakdown, the indicator of the instability of travel times, is treated as the risk, whereas travel time variability, the indicator of the uncertainty of travel times, is considered as the consequence of this risk. An analytical formula, using risk assessment technique, explicitly expresses the cost of travel time unreliability as the sum of the products of the consequences (i.e. variability) and the corresponding probabilities of breakdown. It provides a novel measure of travel time reliability and is applicable in network performance evaluations. An empirical example based on a large dataset of freeway traffic flow data from loop detectors shows that the developed travel time reliability measure is both intuitively logical and consistent. 相似文献
185.
186.
J. De Arizon O. Verlinden P. Dehombreux 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2007,45(9):849-866
One of the most important maintenance costs in tramway transport comes from wear of wheel profiles. In the highly competitive railway market, the prediction of wear is then a major concern of the constructors. In this article, we present and compare four models well adapted to tramway conditions, involving contacts on the rolling tread and on the flange with very different sliding and pressure conditions. Moreover, all models can be implemented from the natural outputs of the railway simulation packages classically used in industry for the dynamics design of the vehicles. The first one, proposed by Jendel, is based on the well-known Archard's wear model. Enblom continues Jendel's approach by taking into account the contribution of wheel deformation on the sliding velocity. The last two models, developed by Zobory, and Pearce and Sherratt, determine the wear from the energy dissipation in the contact area. The models are first compared on a theoretical basis and, for that purpose, are rewritten in a common form. Two cases are distinguished: mild wear as arising on the rolling tread and severe wear as arising on the flange. The models are also compared in the practical case of an urban transport vehicle running on circular tracks with different curve radii. Although the models show equivalent trends according to the theoretical study, important discrepancies appear between estimated wear depths. All models are actually dependent on experimental coefficients and it is likely that they were estimated in different conditions. On the other hand, a reasonable agreement can be found in some particular conditions. As an example, Zobory's, Enblom's and Jendel's models are very close to each other in severe wear conditions. This work shows that a general and reliable model could probably be developed from all positive aspects of the existing ones. 相似文献
187.
A. D. De Pater 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1974,3(3):123-140
The dynamical behaviour of the longitudinal motion of a long train on which tractive or braking forces apply, often is investigated by representing the train by a model consisting of a continuous bar in which longitudinal vibrations can occur. In the present publication a model consisting of a chain of material points and springs is proposed. It can be investigated by means of difference equation methods and of Laplace transformations. In certain respects the discrepancies of the results with those obtained for a continuous model, are considerable and it may be concluded that a more complete investigation of the discrete model is necessary. 相似文献
188.
Sergio?Jara-DíazEmail author Beatriz?Tovar De La Fé Lourdes?Trujillo 《Transportation》2005,32(3):275-291
Cargo handling in ports is a multioutput activity, as freight can arrive in many forms such as containers, bulk, rolling stock, or non-containerised general cargo. In this paper, the operation of cargo handling firms in a Spanish port is analysed through the estimation of a multioutput cost model that uses monthly data on three representative firms located at the Las Palmas port. This permits the calculation of product specific marginal costs, economies of scale (general and by firm) and economies of scope, which help identifying optimal pricing policies and the potential cost advantages of increasing production. 相似文献
189.
对有平衡重转体施工的吊钟岩特大桥主要部位进行受力检算,并对其独特的平面轴心转动体系进行改进优化,确保整个转体过程的安全、顺利和方便. 相似文献
190.
The identification of factors influencing destination choice: An application of the repertory grid methodology 总被引:1,自引:0,他引:1
A common problem of all cognitive-behavioural models of destination choice is that of the identification of factors influencing the behaviour of interest. This paper considers the applicability of Kelly's repertory grid methodology to identify the factors influencing consumer choice of shopping centres. Firstly, some methodological issues in the assessment of the relative importance people attach to certain variables in deciding where to shop are discussed. Secondly, the main findings of an application of the repertory grid methodology are presented. The paper concludes by discussing some implications of the measurement of the determinants of choice behaviour and the construction of mathematical models of destination choice. 相似文献