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151.
Fishing has been and is still one of the most dangerous of all human activities. In the field of fishing safety policy, it is acknowledged that the development of a working legal framework of reference is a vital prior condition for the implementation of measures aimed at its improving safety. However, the research work on fishing safety does not have at disposal records of a sufficient number of accidents and in most cases is not comparable from one country to another. Moreover, there is no work that focuses on a global view of fishing safety. The aim of the present work is to outline the state-of-the-art in fishing safety. To this end, aspects of fishing safety which are a major concern of institutions, organizations and researchers alike are analysed. Thus, several questions are addressed, such as: what institutional policy is given to the activity of the fishing sector to improve safety; what aspects and/or parameters are normally used to analyse fishing accidents; what is the usual spatial domain of this analysis; and what are the topics of the research carried out in fishing safety? The results of this analysis, among other aspects, identify eight specific lines of research followed in fishing safety and five which deal with aspects of safety at sea related to the fishing sector.  相似文献   
152.
以凡纳滨对虾中提取的N-乙酰-β-D-氨基葡萄糖苷酶(NAGase,EC 3.2.1.52)为研究对象,以对-硝基苯-N-乙酰-β-D-氨基葡萄糖苷(pNP-NAG)为底物,考察了几种养殖常用维生素对该酶活力的影响.结果表明,VB12、烟酸、核黄素等对酶活力基本上没有影响;而VB1、VB6、抗坏血酸等对该酶活力均有不同程度的抑制作用.随着抑制剂浓度增大,酶活力呈指数下降,测定导致酶活力下降50%的抑制剂浓度(IC50)分别为16.0、13.5、37.5mmol/dm3.进一步研究了VB6的抑制作用动力学,结果显示:VB6对酶的抑制作用为非竞争性可逆抑制,其对酶抑制常数(KI)为 15.2mmol/dm3.该研究对凡纳滨对虾的人工养殖具有一定的参考价值.  相似文献   
153.
154.
Today, ocean and coastal marine resource management is extremely complex. Marine resource managers are charged with conserving and managing many diverse species. Southern kingfish (Menticirrhus americanus), commonly known as whiting, are found from southern New England to Florida. During the fall through winter, western North Atlantic right whales (Eubalaena glacialis) are primarily found in the coastal nearshore waters off South Carolina, Georgia, and Florida, overlapping the whiting's range and habitat.  相似文献   
155.
Further development of the large, surface-tethered sediment trap (NetTrap) employed as part of the MedFlux program is described whereby the large collection capacity of the NetTrap is combined with an Indented Rotating Sphere/Sample Carousel (IRSC) sediment trap (IRSC–NT). This trap is capable of collecting particle flux either in a time series or settling velocity mode; settling velocity mode allows the collection of particles that fall within discrete settling velocity intervals. During short field deployments in the Mediterranean Sea the IRSC–NT configured in the settling velocity mode successfully collected unpoisoned samples for chemical and microbiological experiments. In addition to the development of the IRSC–NT, particle-settling behavior above and below the swimmer-excluding IRS valve was tested during on-deck experiments using a specially constructed water-tight trap. Chemical analyses of settling materials (published elsewhere) suggested that separation of particles by settling velocity was achieved. However, due to the motion of the ship, it was not possible to directly measure particle-settling velocities within the trap. Particle release from the IRS did not bias the apparent settling velocity spectrum. Rotation of the IRS did not engender turbulence at the surface of the sphere or within the skewed funnel below. Tests of different ball designs over the course of the MedFlux program showed that a “ridge and saddle” pattern was optimal for efficiently transferring particles under the IRS seal while still reducing swimmer entrance to the collection funnel. The large size of the IRSC–NT did not prevent it from drifting effectively with the current. Several modifications of the present design are proposed that should improve the accuracy of the settling velocity measurements.  相似文献   
156.
The MedFlux project was devised to determine and model relationships between organic matter and mineral ballasts of sinking particulate matter in the ocean. Specifically we investigated the ballast ratio hypothesis, tested various commonly used sampling and modeling techniques, and developed new technologies that would allow better characterization of particle biogeochemistry. Here we describe the rationale for the project, the biogeochemical provenance of the DYFAMED site, the international support structure, and highlights from the papers published here. Additional MedFlux papers can be accessed at the MedFlux web site (http://msrc.sunysb.edu/MedFlux/).  相似文献   
157.
SZF型方位传感器方位定标测试方法   总被引:1,自引:0,他引:1  
文中简要介绍了SZF型方位传感器的主要组成及工作原理,针对方位传感器在实验室内如何定标与测试给出了行之有效的计算机自差校正方案及实施方法,经过了大量的实际应用,该方法已经成为SZF型传感器的定标测试过程的重要步骤.  相似文献   
158.
为了综合确定平北地区的主力烃源岩,深化其油气成藏动力学过程研究,在烃源岩分布特征及有机质丰度、类型和成熟度分析的基础上,应用舍油气盆地数值模拟技术,定量恢复了研究区主要烃源岩层系的生排烃历史。研究表明,平北地区主要发育始新统平湖组、渐新统花港组两套烃源岩系,其中平湖组暗色泥岩为主力烃源岩,具较高的有机质丰度、成熟度、生排烃强度与排烃效率;以平湖组为源岩的油气系统应是本区油气勘探的主要目标。  相似文献   
159.
针对层剥算法从海水声回波记录中反演海温垂直结构特征的不稳定问题,利用自适应搜索算法ASM(Adaptive searching method),从声回波记录中提取海温垂直结构的稳定冲激响应,然后利用层剥算法对所得冲激响应进行反演,得到海温垂直结构的声特征,结果表明,该方法可以较好地解决层剥算法反演的不稳定性问题。  相似文献   
160.
根据粤西沿海4个海洋站潮位资料分析、讨论了“灿都”台风风暴潮特征:利用改进的Jelesnianski风场,并采用耦合天文潮模拟与非耦合天文潮两种方案,对1003号台风“灿都”进行模拟、分析,模拟结果显示:在改进的杰氏风场驱动下,两种预报结果误差都比较小,但耦合天文潮预报结果优于非耦合天文潮预报结果.  相似文献   
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