避风型渔港避风因素浅析

我国的东南沿海是最容易遭受热带气旋影响的脆弱地带,每年的5-11月,都会遭受热带气旋的影响,对渔港、渔船和渔民构成严重威胁.而渔港的避风能力是渔民最为关心的问题,通过近几年登陆我国的强台风等级以上的热带气旋对渔港、渔船及渔民造成损失的实例分析,从防波堤设计标准、避风锚地的底质、锚泊方式等3个方面对避风型渔港的避风因素展开讨论,得到了有价值的结论,为渔港、渔船和渔民减少灾害,为政府建设避风型渔港决策提供科学依据.     

渔用高强度聚乙烯和普通聚乙烯编织线的拉伸力学性能比较试验

渔用高强度聚乙烯编织线（以下简称HSPE编织线）和普通聚乙烯编织线（以下简称PE编织线）的拉伸力学性能比较试验结果表明,在同等编线工艺（编织线捻距为27mm、线股结构为3×16、线芯用丝数量为7和线芯为不加捻的平行丝束）条件下,规格为“HSPE-37tex×3×16＋7”HSPE编织线断裂强力、单线结强力分别比规格为“PE-37tex×3×16＋7”PE编织线增加了10.0%和9.1%,而前者的断裂伸长率比后者减少了11.3%;在同等编线工艺（编织线捻距为30mm、线股结构为4×16、线芯用丝数量为18和线芯为不加捻的平行丝束）条件下,规格为“HSPE-37tex×4×16＋18”HSPE编织线断裂强力、单线结强力分别比规格为“PE-37tex×4×16＋18”PE编织线增加了8.1%、6.1%,而前者的断裂伸长率比后者减少了13.3%;HSPE编织线较PE编织线具有强力优势,HSPE编织线在渔具或网箱上推广应用具有可行性。     

渔船备件费用灰色马尔可夫预测模型与应用

在渔船备件费用灰色预测的基础上,结合马尔可夫链预测方法,建立渔船备件费用灰色马尔可夫预测模型,该模型兼有灰色预测和马尔可夫链预测的优点。实例计算证明,渔船备件费用灰色马尔可夫预测模型的预测精度高于灰色预测模型预测精度,模型可以用于渔船备件费用预测。     

编线工艺对渔用高强度聚乙烯编织线拉伸性能的影响

2007年3月~2008年12月在东海水产研究所开展了编线工艺对渔用高强度聚乙烯(HSPE)编织线拉伸性能的影响研究。结果表明,在试验捻距范围(公称直径3.0 mm和3.9 mm编织线的试验捻距范围分别为11.1~29.2 mm、16.4~48.5 mm)内,若其它条件(包括线股结构、线芯用丝数量和线芯结构等)相同,则以不同捻距编织的相同公称直径渔用HSPE编织线的断裂强力及单线结强力均随捻距的增加而增加,而断裂伸长率及线密度则随捻距的增加而减小;多项式回归方程显示,断裂强力与捻距、单线结强力与捻距均显示较好的相关性(R2≥0.987 7)。在线芯用丝数量范围(公称直径3.0 mm和3.9 mm编织线的试验用线芯用丝数量范围分别为0~36、0~64)内,若其它条件(包括线股结构、捻距和线芯结构等)相同,则以不同线芯用丝数量编织的相同公称直径渔用HSPE编织线的断裂强力、单线结强力及线密度均随线芯用丝数量的增多而增加,而断裂伸长率则随线芯用丝数量的增加而减小;多项式回归方程显示,断裂强力与线芯用丝数量、单线结强力与线芯用丝数量均显示较好的相关性(R2≥0.969 5)。若其它条件(包括线股结构、捻距和线芯用丝数量等)相同,则将线芯结构由不加捻的平行丝束改为捻度为32 T/m的线股后,公称直径2.5 mm渔用HSPE编织线的断裂强力、单线结强力、断裂伸长率和线密度均有一定的增加。捻距、线芯用丝数量及线芯结构对渔用HSPE编织线拉伸性能的影响较大。     

Quantifying subjective human dimensions of recreational fishing: does good health come to those who bait?

Recreational fishing is a popular sport and leisure activity in many countries worldwide. There has been growing interest by recreational fishing groups and researchers in the perceived physical and psychological health and social (or ‘biopsychosocial’) benefits of recreational fishing. However, quantifying the key subjective ‘human dimensions’ of fishing that satisfy both the needs of recreational fishing groups and fishery managers is a major obstacle. We propose the use of psychometrically valid health‐related quality of life (HRQOL) measures widely used in the medical and health sciences – namely the Short‐Form Health Survey (SF‐36) – as rapid, reliable and cost‐effective instruments for quantifying HRQOL of recreational fishers. The widespread use of SF‐36 and availability of population normative data allows comparisons of the HRQOL of recreational fishers across multiple temporal and spatial scales, with participants of other activities, and the general population. The use of such measures in periodic surveys allows the biopsychosocial status of a recreational fishery's participants to be assessed using a modified Kobe plot, a graphical format that is easily interpretable and consistent with existing reporting formats used in fisheries stock assessment. Future biopsychosocial research in recreational fisheries can further benefit from interdisciplinary collaboration to develop a suite of standardized psychometrically valid and reliable instruments for assessing specific issues that commonly affect recreational fisheries from regional to international scales, such as drivers of fisher motivation, behaviour and satisfaction.     

玻璃钢渔船舭龙骨连接形式的研究

在对玻璃钢渔船舭龙骨连接形式调查研究的基础上,根据舭龙骨在水中所起到的阻尼作用,计算渔船舭龙骨板所爱的应力;并根据４种玻璃钢骨架的剥离试验数据,计算出玻璃钢渔船舭龙骨的连接强度。将计算结果与试验结果相比,选出了适合不同玻璃钢渔船的舭龙骨连接形式。     

超高分子量聚乙烯渔网线捻回角与强力的初探

本文叙述了采用 8种网线复捻捻回角的超高分子量聚乙烯渔网线强力性能的试验结果。经分析可见 ,网线的断裂强力、单线结强力均与捻回角的余弦呈回归关系。以网线的断裂强力性能为主 ,兼顾网线的单线结强力、断裂伸长率等性能参数 ,比较UHMWPE、普通聚乙烯和聚酰胺三种纤维制成网线后 ,它们的强力利用率均应 >6 5 % ,由此得出制作超高分子量聚乙烯渔网线合理的捻回角区间为 18°～ 2 1°     

The status of the freshwater pearl mussel Margaritifera margaritifera Linn. in Scotland

1. One hundred and sixty rivers in Scotland with historical records of freshwater pearl mussel Margaritifera margaritifera were surveyed between 1996 and 1999 for the presence of the species. 2. M. margaritifera populations were classed as either ‘extinct’ (no mussels remaining), ‘not currently viable’ (ranging from only dead shells present to no juveniles present, regardless of the number of adults found), or ‘functional’ (at least one juvenile was found, regardless of the overall numbers of adults present). 3. M. margaritifera populations could be classed as ‘functional’ in only 52 rivers (34% of total surveyed) and in only 17 of these were juveniles below 20 mm (5 yrs old) present. Furthermore, in only 10 of these functional rivers were mussels also still considered either to be common or abundant and these included both large easterly‐flowing rivers and small western rivers and streams. 4. In approximately two‐thirds (101) of the 155 rivers occupied 100 years ago, M. margaritifera is now extinct or is about to become extinct. Furthermore, analysis indicates that the rate of mussel population extinction has accelerated since 1970, with a recent average of two mussel river extinctions per year. 5. The predominant threat to the mussel populations has undoubtedly been pearl fishing. This has been occurring at every river, even in the most remote northwest areas, where most of the ‘functional’ populations remain. Recent legislation has provided full protection to M. margaritifera, so that all pearl harvesting is now illegal. 6. Locally, river engineering and host salmonid stock decline poses a serious threat and eutrophication has already eliminated populations in southern and eastern Scotland. 7. In every part of its global range, M. margaritifera has declined substantially and is now either threatened with extinction or is highly vulnerable. Based on recent estimates from across the species range, it appears that Scotland now probably holds at least half of the world's remaining functional M. margaritifera populations. Copyright © 2000 John Wiley & Sons, Ltd.     

A review of reported effects of pelagic longline fishing gear configurations on target,bycatch and vulnerable species

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