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1.
In an earlier paper, we presented a statistical study dealing comprehensively with the so-called “artisanal fleet”, with data on the typology of vessels and on the extractive effort. In this paper, we focus our research on safety and working conditions.Although numerous factors are known that can directly influence the health of the sailor or fisherman, and that are present one way or another in both the fishing and merchant fleets, it is necessary to address in particular the problem of coastal fishermens’ health in order to identify areas of health and safety that need to be improved. The results of this analysis, among other aspects, identify the injuries associated with machinery, tools, nets and protection devices, the health status, the life styles and the working conditions.  相似文献   

2.
This paper elaborates on results of a recent risk analysis study for RoPax vessels, carried out as part of the activities of the SAFEDOR Integrated Project, targeting possible improvements on safety levels following large scale flooding. The study is based on a comprehensive analysis of accident statistics for the period 1994–2004, through which a high-level risk model (in the form of event trees) is established. This is then used to determine the current safety level of RoPax vessels (in various risk metrics, such as individual risk, potential loss of life and on an F–N curve), reconfirming that even though safety levels are improving, risk is still “high in the ALARP region”. In search of ways to further improve the situation possible risk control options are examined, by performing a sensitivity analysis on the effects of the Attained Index of Subdivision A onto the safety levels and by evaluating their cost-effectiveness.  相似文献   

3.
Safety at sea is a serious issue for the commercial fishing industry; it ranks highly in all assessments of occupational dangers including risk-taking, injuries, and fatalities. This paper examines the impact of fisheries management on safety at sea and the use of fishermen's input in the safety regulatory and management process. Using case study techniques of analysis, 22 boatowners, captains and crew all with a minimum of 10 years experience in the commercial fishing industry and from a common New England port (New Bedford) are interviewed. Findings strongly suggest that regulations that have been primarily designed to reduce pressure on fish stocks may also result in increased pressure on fishermen and decreased safety at sea. Attitudes about the role of the New England Fisheries Management Council and improvements to the safety regulatory and management process particularly with regard to the increased participation by fishermen are also examined.  相似文献   

4.
Due to a high number of fatalities and personal injuries, commercial fishing is considered a risky occupation. In the Norwegian context, work-related fatalities have been especially prominent in the coastal fleet. Despite high statistical risk, many fishermen claim they do not worry about their work being dangerous. Applying a qualitative approach, this article argues that shared beliefs and practices such as common sense, taking precautions, evaluating risk as well as relying on each other through cooperation on board and amongst vessels, can be understood as integrated or institutionalized ways of dealing with potential risk. These elements interact with the individual's personal experiences, and influence the fishermen's perceptions of the dangers at hand. The points presented here, may be a part of the reason why fishermen do not necessarily see the need for formal regulations aimed at improving their safety.  相似文献   

5.
The St. Lucia Estuary is Africa’s largest estuarine system and is currently experiencing the stress of prolonged freshwater deprivation, manifested by extremely low water levels and hypersalinity. These unprecedented conditions have raised questions regarding the trophic functioning of the ecosystem. Despite the substantial amount of research previously undertaken within this system, no studies of food web structure and function have yet been documented. This study therefore aimed to examine the food web structure of the St. Lucia estuary system through the use of carbon and nitrogen stable isotope analysis. Analysis of carbon isotope ratios indicates that benthic carbon sources are most utilised at sites with low water levels and generally higher salinity (Catalina Bay, Charter’s Creek). Conversely, the estuarine region of the mouth and Narrows, with its elevated water levels and lower salinity, still sustains a viable pelagic food web. Analysis of δ15N ratios indicates that the number of trophic transfers (food chain length) might be related to water levels. Overall, the study provides a greater understanding of the ecological processes of this complex estuarine lake, which may allow for future comparisons of trophic functioning under drought and normal/wet conditions to be made.  相似文献   

6.
The northern Portuguese shelf, between 41°N and 42°N, is characterised by the presence of a mid-shelf mud deposit, the Douro Mud Patch (DMP). Observations conducted between July 1996 and June 1999 under the framework of project OMEX II–II, are used to examine the impact of the dynamic processes in the lower water column, particularly on the DMP. The typical wave conditions observed during the winter maintain a highly energetic environment, capable of promoting the erosion of fine sediments at mid-shelf depths. However, the bottom nepheloid layers generated beneath these waves only extend a few meters above the bottom and are contained within rocky outcrops with similar heights that fringe the outer shelf. Each year there are about ten storms, mostly associated with southerly winds that create downwelling conditions over the shelf. The waves associated with these storms produce shear velocities over 3 cm/s at mid-shelf and bottom nepheloid layers which extend a few tens of meters above the bottom and spread offshore, over the outer shelf and upper slope. A rough estimate suggests that these events account for an offshore export of about 20×106 kg of fine sediments each year (equivalent to 1–2% of sediments trapped at DMP).  相似文献   

7.
A survey of the safety culture and hazard risk perception has been carried out involving 77 maritime pilots around Australia and New Zealand, representing more than the 20% of the maritime pilots in each country, in proportional geographic distribution. In 82% of the cases, interviews were carried out face-to-face, based on a questionnaire designed to be completed in less than 1 hour. Questions on 4 different aspects were asked, relating to each pilot's professional background, safety culture and perception of risks, navigation and pilotage hazards and their perception of the pilot's role. The responses indicated that there are issues with regulator identification, commercial pressures on pilots in some locations, incident reporting mechanisms and feedback, training opportunities and improved bridge resource management. In addition to reviewing comments made by pilots, the paper also presents recommendations for consideration in improving operational performance and safety of navigation in ports and regulated waterways. These recommendations can be used by regulators to improve their performance concerning pilotage matters and understand pilots’ concerns.  相似文献   

8.
对传统可拆式板式换热器进行了改良,以适用于海洋温差能发电系统工况,并对改良后的板式换热器进行了理论数值分析。研建了海洋温差发电系统测试平台,对系统内的换热器换热特性进行测试,在不同工况下对换热器换热特性进行了实验研究,得到了板式换热器瞬态运行特性,同时还得到了换热器换热特性随热流密度的变化曲线及压降随工质流量的变化关系。结合实验数据拟合了换热器换热特性经验关联式和压降随工质流量关联式,预测值和实验值偏差均在20%以内。结果表明:在实验系统运行工况范围内,换热器的换热系数随着热流密度的增加而增大,当热流密度大于3 kW/m2时,换热系数随热流密度变化的曲线斜率变小;换热器压降随着工质流量增大而增加,压降随工质流量变化的曲线斜率变大。  相似文献   

9.
The dangers associated with commercial fishing are well documented, and fishermen consistently face one of the highest job-related mortality risks of all US occupations. This study explored fishermen's perceptions of these risks in a representative sample of Maine commercial fishing vessel captains. Data were collected on sociodemographic characteristics and risk preferences during sea boardings of working commercial fishing vessels (n=233) along the full extent of the Maine coastline. Trends in perceived risk were explored across the various sociodemographic categories. Fishermen in this study consistently undervalued their true occupational risk, and rated it as average despite consistent evidence to the contrary. Those more likely to downgrade the risk of fishing included state registered vessels and those found to be non-compliant with existing safety regulations. Less educated fishermen and those who come from a fishing family were also more likely to underrate the risks, as were those fishermen who displayed risk-loving tendencies in other facets of their lives such as smokers and those who did not use seat belts. Middle-aged fishermen were also more likely to underrate the risk than the youngest and oldest groups, suggesting that overconfidence grows and then wanes over time. The results of this study strongly suggest that the current safety training and awareness programs targeting fishermen are inadequate. Furthermore, widespread voluntary participation in organized safety training is unlikely since the majority of fishermen believed that the risks were not relevant to their own activities.  相似文献   

10.
本文采用原位生态学研究方法分析两种较为典型的对虾养殖模式—高位池精养模式和生态养殖模式沉积物中碳、氮元素的变化和其对底栖细菌的影响.结果表明:(1)在两种养殖模式下沉积物中碳元素含量都是呈上升趋势,高位池精养模式中C∶N值呈下降趋势,而生态养殖模式中C∶N值则呈上升趋势.(2)底栖细菌的呼吸量及其生物量变化呈显著正相关.单位生物量的底栖细菌代谢力变化和沉积物中C∶N值有关.在高位池精养模式中,沉积物C∶N值较高(>16.59),单位生物量底栖细菌代谢力保持恒定;在生态养殖模式中,沉积物C∶N值较低(<15.58),单位生物量底栖细菌代谢力随C∶N值的上升而增加.  相似文献   

11.
The Panama Ship Registry has its origins in the year 1917. Nowadays, Panama has the largest vessel registry in the world. The second placed registry in the world ranking is Liberia, which does not have even half the number of Panamanian ships. In this Centennial, the aim of this paper is to analyse the evolution of the Panamanian Registry, the structure of the Panamanian-flagged fleet and the level of compliance with international standards in relation to maritime safety and working conditions. To undertake the analysis, two different qualitative and quantitative approaches are compared and integrated for the evaluation of the Panama Ship Registry: the degree of ratification and enforcement of the Conventions and Recommendations of the International Maritime Organization and International Labour Organization, and the results of Panamanian flagged vessels in inspections carried out within the major Port State Control Memoranda of Understanding. This paper fills a research gap by discussing an approach to the concept of flag of convenience and flag State, Panama is more an international registry, whose role is becoming less important from the points of view of safety or working conditions. The fleet performance evolution has been very positive as evidenced by the data presented in this article regarding Port State Control.  相似文献   

12.
More and more deep-seated long submarine tunnels are under construction, which greatly promotes the development of tunneling technology. The complex geological conditions and frequent geological disasters have become great challenges during submarine tunnel excavation. Among them, casualties and economic losses caused by water inrush are on the top levels in all kinds of tunnel geological disasters. Escape routes after water inrush from the working face during submarine tunnel excavation are investigated and optimized in the present study. Numerical simulations are performed using the FLUENT software to probe water flow characteristics after inrush. Two common cases of water inrush during double-line submarine tunnel excavation are researched. The variation rules of velocity and pressure in the tunnels after inrush are analyzed and discussed. The optimized escape routes are achieved. Finally, the water movement laws after inrush from the working face under different excavation situations are further discussed by comparing the two case studies. Water inrush of high velocity occurs on one working face of the double-line submarine tunnel, and the research results are as follows: (1) The velocity close to the tunnel side wall is the minimum, while it is the maximum in the middle position. (2) The pressure changes greatly at the intersection area of the cross passage and the tunnels. (3) The velocity and pressure nearby the working face without water inrush are both small. (4) The velocity at the high location of the cross passage is relatively small.  相似文献   

13.
Due to the shipping industry's international legal framework, there are loopholes in the system, which can increase the risk of incidents with high economic costs due to the substandard operation of vessels. This article uses duration analysis and through the creation of ship life cycles provides insight into the effectiveness of inspections on prolonging ship lives. The analysis accounts for fluctuations in the relevant economic environment and the (possibly time-varying) ship particulars. It is based on a unique dataset containing information on the timing of accidents, inspections and ship particular changes of more than 50,000 vessels over a 29-year time period (1978–2007). The results reveal that the shipping industry is a relatively safe industry but there is a possible over-inspection of vessels. The effect of inspections varies across ship types and the prevention of incidents with high economic costs can be improved by a coordinated approach of all types of inspections that are performed which allows the decrease of unnecessary inspections. Further, more emphasis should be placed on the rectification and follow-up of deficiencies and the implementation of the ISM code. Another added benefit for the industry would be to improve transparency related to class withdrawals and class transfers for all classification societies. Another interesting finding is that for the majority of ship types, an increase in earnings decreases the incident rate. This is in contrast to the industry perception of the impact of earnings.  相似文献   

14.
In the last few decades, use of foreign labor in the Norwegian fishing fleet has increased. As fishing is a high-risk occupation, this article investigates a prevalent question regarding how the increased share of foreigners affects communication and safety on Norwegian fishing vessels. The article shows that multilingual crews and varying language proficiencies are not perceived by the fisheries actors themselves as risk factors in terms of safety in everyday operations. Fishing experience, hybrid language and body language compensate for language challenges and contribute to fishers' feeling of safety.  相似文献   

15.
Biofloc technology has been applied successfully in the intensive aquaculture of several fish and shrimp species. The growth of heterotrophic microorganisms can be stimulated through adding extra carbon, which reduces the nitrogen level in the water and provides microbial protein to the animals. However, most of the studies and practical applications have been conducted in freshwater and marine environment. This paper focused on brine shrimp Artemia that lives in high salinity environment together with other halophilic or halotolerant microorganisms. The effect of carbon supplementation on Artemia growth, water quality, and microbial diversity of biofl ocs was studied in the closed culture condition without any water exchange. The salinity of the culture medium was 100. A 24-d culture trial was conducted through supplementing sucrose at carbon/nitrogen (C/N) ratio of 5, 15, and 30 (Su5, Su15, and Su30), respectively. The culture without adding sucrose was used as a control. Artemia was fed formulated feed at a feeding ration of 60% recommended feeding level. The results showed that sucrose supplementation at higher C/N ratio (15 and 30) signifi cantly improved the Artemia survival, growth and water quality ( P <0.05). Addition of sucrose at C/N ratio of 15 and 30 significantly increased biofloc volume (BFV)( P <0.05). The Illumina MiSeq sequencing analysis showed that supplementing carbon at C/N ratio of 15 had a better total bacterial diversity and richness, and shaped the microbial composition at genera level. This study should provide information for studying the mechanism of biofloc technology and its application in high salinity culture conditions.  相似文献   

16.
Identification of regional collision risk in water area is of significance for the safety of navigation. However, traditional risk identification models are subject to the limitations in accuracy, short-term identification and traffic characteristics. Herein, a framework was put forward to identify regional collision risk instantaneously based on AIS data. The vessels were clustered by using the spatial clustering method. Afterwards, the framework was divided into two steps. Firstly, collision risk of each cluster was obtained by collision risk and contribution of the vessels within the cluster. An analytical method was adopted to identify collision risk of each vessel from the perspective of vessel pairs. Contribution of each vessel was determined by using improved Shapley value method in game theory. Secondly, regional collision risk was obtained by collision risk and contribution of each cluster. Case studies were carried out based on the AIS data of Northern Yellow Sea in China to validate the validity of the proposed framework. The results show that the proposed framework can effectively identify collision risk in water area, presenting the potential for collision risk monitoring and collision risk analysis of water area.  相似文献   

17.
随人工智能技术发展,智能船舶因其无人化、智能化的特点而与传统国际法律制度产生碰撞。当前,国际海事组织将制定“海上自主水面船舶规则”工作提上日程,航行安全问题作为其中的高度优先事项,受到各国广泛关注。船舶适航作为承运人的主要义务之一,是保障航行安全的先决条件。但智能船舶是否需要符合适航标准,如果适用会产生哪些法律障碍并如何解决等诸多问题亟待研究。对此,应修订《国际海上避碰规则》并明确智能船舶适船技术标准,明确岸基操作人员的法律地位并制定其资格取得、培训、值班标准,明确安全配员标准及需船员在船承担的职责的履行方式。  相似文献   

18.
针对海洋温差能可利用温差小,利用效率低的问题,本文提出了一种采用非共沸混合工质的新型海洋温差能回热循环,并基于热力学定律对提出的热力循环进行热力学分析。选取蒸发压力、工质的质量分数作为变量,对提出的热力循环进行热力学分析研究。研究结果表明:以工质质量分数为变量时,循环热效率和系统净输出随蒸发压力的增加先增大后减小,系统热效率在工质质量分数为0.91时取得最大值5.28%,净输出功在浓度为0.96时取得最大值3.83 kW。以蒸发压力为变量时,循环热效率和系统净输出随工质质量分数的增大先增大后减小,系统热效率在蒸发压力为0.595 MPa时取得最大值5.26%,净输出功在压力为0.58 MPa时取得最大值3.57 kW。在相同运行控制参数下与Uehara循环、Yoon循环进行对比,提出的循环系统热效率最佳。提出的热力循环系统分析结果可对提高海洋温差能利用效率提供理论依据和参考。  相似文献   

19.
Knowledge about the existing safety culture in a maritime organization such as in shipping companies or on board ships can enable the formulation of effective interventions to maintain and improve safety culture and safety in the organization. When assessing the safety culture, questionnaires developed for this purpose are often used. This paper proposes a work process that facilitates the analysis and interpretation of the relationships between safety culture aspects using questionnaire data. The work process includes the use of variable cluster analysis where the cluster solutions are presented in dendrograms. These were found to be an excellent way to visualize complex relationships in the quantitative data and to facilitate the understanding of the safety culture concept. Results are presented from applying the statistical process to safety culture data from six Swedish ships in international traffic. The visualized safety culture results can enable group discussions about safety on different organizational levels and can constitute an important input to the continuous improvement processes for safety and safety culture.  相似文献   

20.
The relatively remote and geographically isolated lower southern Lau islands of Fiji rely on maritime transportation for their economic success and social wellbeing. This paper explores the feasibility of implementing a Material Flow Management (MFM) framework to sustainable shipping and the possibilities for addressing the socio-economic development needs of the relevant island communities. The research question is: how can a regional MFM framework for hybrid powered maritime vessels be implemented effectively to promote ecological quality improvements and local added value for Fiji's lower southern Lau islands? The mixed methods research uses a quasi-experimental design, with most data collected on site during a March 2015 field study of the lower southern Lau route. The findings are applied to a tailor-made MFM framework that demonstrate the viability and effectiveness in achieving seven key aims: (1) activate regional potential; (2) increase system efficiency; (3) decrease operating costs; (4) create stakeholder network; (5) create and maintain jobs; (6) support innovative small and medium enterprises (SMEs); and (7) create sustainable economy/society. The results validate the MFM framework as a potential model of sustainable sea transport for this particular route that can be expanded upon for other domestic and regional shipping routes. The author concludes that further research and the development of pertinent socio-economic indicators based on these findings will support a more robust MFM model as it applies to sustainable sea transport.  相似文献   

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