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101.
M. Antoni 《Recherche - Transports - Sécurité》2012,28(2):101-118
In this article, we discuss on how to solve the following problems: the checks and tests before putting the safety facilities into service, and the results of these tests which are essential, time consuming and may show great variations among each other. Economic constraints and the increasing complexity associated with the development of computerized tools tend to limit the capacity of the classic approval process. In practice, a reduction of the test cover rate is observed. The method presented in this article makes it possible to formally validate the new computerized mechanisms of the existing French interlocking systems with real-time functional interpreted Petri nets. The aim of our project was to provide SNCF with an operating method for the formal validation of interlocking systems. A formal proof method by assertion, applicable to our interlocking system, which covers equally the specification and its real software implementation, is presented in this article. With the proposed method and its associated tools, we completely verify that the system follows all safety procedures at all times and does not show superfluous conditions. This replaces all plateform tests checks. It is included in the existing testing procedures. The advantages of using this method are the following: a significant reduction of testing time and of the related costs, an increase of the test coverage rate (determinisitic safety vs. probabilistic safety), and an answer to the new demand of railway infrastructure maintenance engineering to modify and validate computerized interlocking systems. The mastery of formal methods by infrastructure engineers is surely a key to prove that additional safety is not expensive. 相似文献
102.
This paper gives a literature review from experimental, epidemiological and naturalistic studies, having tried to measure on the one hand, the impact of mobile phone use on driving and, on the other hand, the risk of accident associated with this practice. The overview of these studies allowed first of all to show that the driving task is altered during the period of mobile phone use, and to quantify the disturbance (experimental studies), then to verify that this disturbance can be at the origin of accidents and quantify this risk (epidemiological studies). The naturalistic studies, consisting in following-up fleet vehicles, give some more explanations and tend to confirm the results. Advantages and limits of each approach are also discussed. 相似文献
103.
Athanasios A. Pallis 《Maritime Policy and Management》2013,40(4):365-380
This paper discusses the European Union's (EU) proposals to improve the efficiency and infrastructure of European ports, and investigates the extent to which these proposals are welcomed by the ports industry. On the one hand, the analysis of the recent EU policy developments makes apparent that the EU is increasingly impinging upon the port industry's life. On the other hand, the findings of the semi-structured interviews with the industry's representatives suggest that although port authorities and port operators remain in principle against a coherent common EU ports policy, the industry believes that certain EU initiatives can enhance the competitiveness of the maritime transport system. 相似文献
104.
BRAXTON C. DAVIS 《Coastal management》2013,41(4):339-354
Area-based management approaches may be beneficial in integrating sectoral, single-purpose laws and regulations; however, these benefits may not be attained if special area designations are equally sectoral or single-purpose in nature. Over 60 types of special management areas were documented under U.S. coastal programs, and a new classification scheme was developed to allow comparisons and analyses across programs. Results indicate that requirements and incentives for special area designations under the Coastal Zone Management Act did little to standardize or influence area-based management systems associated with state and territory coastal programs. Further, the absence of clear patterns within and between coastal programs with respect to special area policies suggests a limited commitment to this important aspect of coastal management. Continued research is needed to document the effectiveness of the various area-based management approaches presented in this article. 相似文献
105.
F. J. GABLE 《Coastal management》2013,41(4):435-456
This article addresses interdisciplinary sustainable aspects of fisheries as part of ocean management. Human-caused impacts and their role as modifiers of living marine resources is discussed. The research note also theorizes about contemporary global change and its prospective biological consequences, especially when coupled with human-induced factors in coastal marine waters. Also addressed is the management and ecological aspects of fish stock populations as part of a large marine ecosystem (LME) in the Northeast United States continental shelf of the Atlantic Ocean with suggestions for an interdisciplinary policy orientation paradigm to foster the sustainability of marine life in the sea. 相似文献
106.
The coastal zone is attractive for human settlement because it tends to be resource rich, providing a good location to generate incomes and livelihoods. Equally, however, it is a complex and powerful natural environment, which means that the coastal zone often becomes a focus of conflict with multiple users competing for limited space and resources. Understanding the causes of, and determining solutions to, the ensuing problems requires inputs from a range of analyses across sectors and disciplines. However, different disciplinary and sectoral approaches frequently use different investigative methods, language, and means of presenting results. This article presents a framework that has been developed in collaboration with Indian institutions over the past three years in an effort to address some of these fundamental problems of analysis and translation into policy action. Key components addressed by the framework are strengthening the capacity to practice, knowing how to proceed and how to find out what needs to be known using experience-based problem solving. 相似文献
107.
ALEXANDROS A. KARAMANLIDIS PANAYIOTIS DENDRINOS ELENI TOUNTA SPYROS KOTOMATAS 《Coastal management》2013,41(3):293-306
Mediterranean monk seal populations have declined dramatically and survive in subpopulations scattered throughout their original distribution. The National Marine Park of Alonnisos, Northern Sporades is the first marine protected Area dedicated to the protection of the species in the Mediterranean. A Monitoring and Awareness Project has been carried out in the area from 1993 to 2000, the results of which have produced a detailed profile of the human usage pattern of the Park and indicated a significant reduction of illegal activities in the area. The pattern of human usage has enabled the monitoring team to adjust their efforts in the Park over time and provided essential baseline data for future management. The combined monitoring and awareness efforts have contributed significantly to the conservation of the Mediterranean monk seal by successfully protecting pupping sites and reducing human-induced mortality of the species in the area. 相似文献
108.
San Felipe marine reserve, in Yucatán, México, is unique, and particularly suited for a case study because the local community created it without a mandate from higher levels of government. This article presents the results of a survey of local interest groups using the method of paired comparisons and rank correlation analysis, to reveal local judgments about the severity of damages to coastal habitats and the level of impacts of activities that cause the damages. The results show that fishers differ significantly from other interest groups in their rankings of the severity of damages to habitats and of impacting activities. These findings suggest that despite the overlapping interests in protecting the resources and the critical habitats, the different perspectives of local interest groups about the severity of damages must be considered in the management of San Felipe marine reserve. 相似文献
109.
Hussein M. Alidina 《Coastal management》2013,41(4):459-470
The current regime of fisheries management and the prospects for attaining a more locally oriented, collaborative system of fisheries management in Diani-Chale, Kenya are examined. At present fisheries management in Diani-Chale is characterized by diminished government capacity for regulation, weakened local institutions, and little ability to exert control over the use of fisheries. Local level management requires the development and use of local institutions that can govern the use of fishery resources. The fish landing sites used by fishers and their associated fishing grounds were identified to be at the appropriate level for resolving fishery management issues. A more formal role for these entities, the clarification of fishing ground tenure and access rights, and support for the development and enforcement of local fishing rules can further local management. The socioeconomic condition of fishers, their fear of losing landing sites, and the continued perception of the imposition of a marine reserve pose barriers to initiatives seeking to further local level management. 相似文献
110.
Derek J. McGlashan 《Coastal management》2013,41(3):221-236
This article considers the issue of economic development as a component of coastal management initiatives in developed countries, focusing on the Forth Estuary Forum as a case study. The evolution of coastal management into integrated coastal management is briefly considered, as is the context of the Scottish coastal management system and a brief discussion of the variations between the different legal systems within the UK. The current hurdles to economic development and the views of developers and economic agencies being considered in the coastal management process itself are highlighted, illustrating the process of integration and the current voluntary regime in the UK, particularly in the Forth Estuary Forum. The article concludes that economic development issues must be taken seriously if coastal management is to be integrated and inclusive. 相似文献