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151.
Maria A. Lambrou Ørnulf Jan Rødseth Howard Foster Kay Fjørtoft 《WMU Journal of Maritime Affairs》2013,12(1):41-61
Port information management is considered a critical instrument towards enabling international transport and trade; thus, various forms of Port Information Systems (PORTIS) have been developed today, namely Port Community Systems, Terminal Operating Systems and Single Window systems. In Europe, the nautical information system SafeSeaNet is viewed as an important e-infrastructure. PORTIS systems are expected to evolve into next-generation technological platforms in order to offer a fully integrated digital environment to a multitude of maritime business actors and public authorities towards more efficient, safe and environment-aware transport and trade infrastructures and services. We propose service-oriented computing and model-driven development techniques as a robust PORTIS modelling and development approach. We present a reference model of PORTIS and a particular enabling methodological and technological framework. The proposed approach has been tested in a maritime single-window case. 相似文献
152.
Abstract A territorial sea comprising 6.7 million acres of offshore lands extending three geographic miles into the Atlantic Ocean three marine leagues (nine geographic miles) into the Gulf of Mexico makes Florida the second largest “oceanowning”; state in the contiguous United States. Florida's history, climate, economic development, and worldwide reputation have evolved from the state's relationship with the sea. The state is now becoming aware that aggressive management of its ocean resources is necessary to preserve the future of that relationship. The purpose of this article is to present some of Florida's recent legal and policy initiatives that have been directed toward better understanding and management of ocean resources and uses. 相似文献
153.
Short sea shipping has begun to receive attention from governments worldwide, as they seek to reduce traffic congestion and greenhouse gases. Despite a long coastline and its interest in international maritime affairs, the Canadian government had, until 2003, placed greater emphasis on resolving the issues of other transport modes. In July 2003, Canada and the United States signed a Memorandum of Cooperation on Sharing Short Sea Shipping Information and Experience. Subsequently, the federal government embarked on an assessment of short sea shipping through a series of workshops. This paper explores the key issues with respect to further development of short sea shipping from a Canadian perspective. It examines the critical limitations and impediments to further growth of short sea services in Canada and trans-border trade with the USA, and identifies a number of questions Canadian policymakers need to answer. 相似文献
154.
Structural pipe-in-pipe cross sections have significant potential for application in offshore oil and gas production systems
because they combine thermal insulation performance with structural strength and self weight in an integrated way. Such cross
sections comprise inner and outer thin-walled pipes with the annulus between them fully filled by a selectable filler material
to impart an appropriate combination of properties. Structural pipe-in-pipe cross sections can exhibit several different collapse
mechanisms, and the basis of the preferential occurrence of one over the others is of interest. This article presents an exact
analysis for predicting the elastic buckling behaviours of a structural pipe-in-pipe cross section when subjected to external
hydrostatic pressure. Simplified approximations are also investigated for elastic buckling pressure and mode when the outer
pipe and its contact with the filler material is considered as a pipe on an elastic foundation. Results are presented to show
the variation of elastic buckling pressure with the relative elastic modulus of the filler and pipe materials, the filler
thickness, and the thicknesses of the inner and outer pipes. Case studies based on realistic application scenarios are used
to show that the simplified approximations are sufficiently accurate for practical structural design purposes. 相似文献
155.
Ioannis K. Chatjigeorgiou Spyros A. Mavrakos 《Journal of Marine Science and Technology》2007,12(4):218-231
This work considers the second-order sum-frequency diffraction problem for a stationary truncated surface-piercing circular
cylinder in bichromatic waves. The solution method was based on a semianalytical formulation of the second-order sum-frequency
diffraction potential. The boundary conditions were properly satisfied by introducing the “locked” and the “free” wave components
of the nonlinear velocity potential. The method was validated by comparing the calculated results with numerical data previously
reported by other authors. Particular attention was paid to the second-order sum-frequency heave forces and the change in
the wave run-up configuration due to the existence of the lower fluid domain underneath the truncated cylinder. 相似文献
156.
Proshanto K. Mukherjee 《WMU Journal of Maritime Affairs》2007,6(2):147-166
Within the comprehensive body of law encompassed by the International Convention on Safety of Life at Sea, 1974 (SOLAS), there
are two regimes that are topical and outstanding in the current maritime milieu. These are the international safety management
and the international ship and port facility regimes, both characterized by two codes serving as the centre of gravity of
each, namely, the ISM Code and the ISPS Code, respectively. In this article the concept of the code as a legal instrument
is perused following which a critical legal analysis is carried out of the two above-mentioned Codes, including their backgrounds,
the evolutionary process culminating into the regimes and their interrelationships. Several anomalies and inadequacies in
the two regimes are identified but in the final analysis it is concluded that both instruments are salutary additions to the
body of convention law generated by the International Maritime Organization (IMO). They will undoubtedly influence the continuing
development of international law in the field of maritime safety and security. 相似文献
157.
Thomas A. Mensah 《WMU Journal of Maritime Affairs》2004,3(1):17-30
The adoption of the International Ship and Port Facility Security Code (ISPS Code) is the latest response of the international
shipping community to the increasing threat posed by acts of terrorism at sea. The ACHILLE LAURO incident of 1985 showed that
the traditional law against piracy was not adequate to deal with new types of unlawful acts against international shipping,
especially those involving acts of terrorism. The 1988 Convention for the Suppression of Unlawful Acts against the Safety
of Maritime Navigation (SUA Convention) and the technical and administrative measures adopted by the Maritime Safety Committee
of IMO in 1986 and 1996 attempted to develop a broader regime to deal with unlawful acts against international shipping.However,
the events of September 11, 2001 showed that additional measures were still needed to prevent terrorist attacks against ships. 相似文献
158.
159.
内破裂的数值模拟与分析 总被引:1,自引:0,他引:1
应用气—波两相流理论,引入计算流体动力学方法中的SIMPLE(Semi—ImplictMethodforPressure-LinkedEquations)方程,并在此基础上进行改进,对压力筒内的内破裂现象进行了系统的研究。本文发展了一套不依赖于试验结果的预报方法,较之以前的理论研究结果有了长足的进展,所采用的模型与假设能用于多种内破裂状况的模拟与预报。本文对一典型的内破状态进行了数值模拟,结合物理现象对模拟结果进行了分析,并与试验作比较。分析结果以一组计算机所绘图形表示,输出结果可作为压力筒结构动力分析的基础,所研制的程序也可作为内破裂问题流—固耦合研究的一大模块。 相似文献
160.
Simulation Approach to the Effect of the Ratio Changing Speed of a Metal V-Belt CVT on the Vehicle Response 总被引:10,自引:0,他引:10
T. Ide A. Udagawa R. Kataoka 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1995,24(4):377-388
In regard to the belt and pulley system of a metal V-belt CVT, the characteristics of the ratio changing speed is obtained by experiments. It is summarized in a practical and simple experimental equation. By using this equation a simulation model is developed to analyze the response of a vehicle with a metal V-belt CVT to a rapid pulley ratio change. The simulation results are in reasonable agreements with experimental results. 相似文献