基于菲涅耳现象的LED集鱼灯最佳入射角研究

为了解决平板式LED集鱼灯安装不合理的现状,使得LED集鱼灯光能得到有效利用,提高诱、集鱼效果,实验分析了海面的菲涅耳现象,利用光学的临界条件原理推导出了菲涅尔公式,并利用透射率和折射率的定义式,得到光通过两个不同介质分界面时透射率和折射率的各分量与入射角的关系式,进而利用MATLAB仿真了光在通过海面时透射率和反射率随入射角改变而变化的函数图像。结果显示,透射光强最大时的入射角为53.6°,可以此入射角指导LED集鱼灯在渔船上的安装。对于平板式LED集鱼灯,安装角度可取36.4°;对于三列式LED集鱼灯,安装角度可取23.6°,相邻两列LED集鱼灯的夹角为160°。     

300W型LED集鱼灯光学特性及其节能效果分析

高效节能型新光源集鱼灯的应用研究是光诱渔业研究的重要内容之一.使用高光谱剖面仪Hyperspectral profiler Ⅱ对所研制的国产300 W型LED集鱼灯的光学特性进行测量,并与1 kW型、1.5 kW型、2 kW型金属卤化物集鱼灯进行比较,表明国产LED集鱼灯具有良好的水中穿透性,能够满足渔业生产需要.根据...     

2种LED灯光诱蓝圆鲹和竹筴鱼的渔获比较

为了探索节能减排的海洋捕捞作业方式,在中国沿海海域做了白光(偏绿光)发射二极管(LED)水下灯和蓝紫光LED水下灯集鱼试验。对比2种等光能LED集鱼灯周围蓝圆鲹(Decapterus maruadsi)和竹筴鱼(Trachurusjaponicus)的渔获,对渔获数据进行t检验分析表明,白光LED灯对蓝圆鲹的光诱效果显著优于蓝紫光LED灯;白光LED灯对竹筴鱼的光诱效果极显著优于蓝紫光LED灯。海上试验结果证实,在实验室水槽中所得的光诱鱼试验结果对海洋捕捞实践具有很好的指导作用。     

2种LED灯的蓝圆鲹和竹荚鱼渔获比较

为了探索节能减排的海洋捕捞作业方式,在中国沿海海域做了白光（偏绿光）发射二极管（LED）水下灯和蓝紫光LED水下灯集鱼试验。对比2种等光能LED集鱼灯周围蓝圆鲹（Decapterus maruadsi）和竹筴鱼（Trachurus japonicus）的渔获,对渔获数据进行t检验分析表明,白光LED灯对蓝圆鲹的光诱效果显著优于蓝紫光LED灯;白光LED灯对竹筴鱼的光诱效果极显著优于蓝紫光LED灯。海上试验结果证实,在实验室水槽中所得的光诱鱼试验结果对海洋捕捞实践具有很好的指导作用。     

水下集鱼灯在近海水体中的光场分布数值模拟

为提高水下集鱼灯光场分布计算精度，本实验采用集鱼灯光谱数据、光度分布数据和海水固有光学参数，基于蒙特卡罗模拟方法构建了新的光场传输数值模拟方法，将光束能量离散成大量光子，通过追踪光子路径计算水下集鱼灯形成的光场强度，并开展水槽实验对计算方法进行了验证。同时，提出了新的集鱼灯光场分布评价指标I_ds和A_ds。利用模型分析了海水的叶绿素a质量浓度、散射作用类型和散射相位函数HG (Henyey Greenstein)中非对称参量g的取值对水下光场分布的影响。结果显示，①叶绿素a质量浓度从1mg/m³增加到5 mg/m³,LED集鱼灯A_5m减少了72.73%,MH集鱼灯A_5m减少了72.17%;LED集鱼灯I_5m减少了66.69%,MH集鱼灯I_5m减少了53.29%。②当海水介质引起的散射类型分别为米氏散射和瑞利散射时，MH集鱼灯I_5m分别为1 058.48和1 020.5 lx,LED集鱼灯I     

LED集鱼灯节能效果及优化应用分析

<正>集鱼灯作为光诱渔船的重要组成,对鱼群能够实现"趋光效应"。目前,我国光诱渔业发展迅速,用于远洋鱿钓作业的渔船多达500多艘。在这些光诱渔船中绝大多数采用的是传统的金属卤化灯作为诱鱼光源,然而由于该类光源发光功率过高导致其耗油量大,光能利用率低。随着能源问题的日益突出导致燃油价格一路上涨,使得越来越多的传统光诱渔船入不敷出,渔民压力节节攀升。随着第四代照明光源LED的诞生,与传统金属卤化灯相比,具有使用寿命     

高品质的“协光牌”集鱼灯是这样产出的

上海嘉宝协力电子有限公司是一家专业从事“协光牌”集鱼灯及相关电器产品生产的中日合资企业。 该公司成立以来,在渔业界广大同仁的大力支持和热情关心下,经过该公司全体员工的共同努力,“协光牌”系列产品已形成批量生产和投放境内外市场。广大用户在使用该产品后反映,其集鱼灯无论就质量、光亮度、色谱等均与日本同类产品相仿。特别需要指出的是:在印度洋试钓鸢乌贼的探捕中,上海水产大学临场对日本产的集鱼灯与该公司“协光牌”集鱼灯进行了比较测试,得出“协光牌”“集鱼灯相对较广的诱鱼范围可能是导致对照试验中(安装)上海嘉宝产集鱼灯一侧产量较好的一个主要原因”。     

综述光诱渔业

光诱渔业在世界各地很早开始,日本、东南亚、北欧各国根据相同的设想利用火光诱捕鱼群。但是,关于集鱼灯的最早记录却始于日本。从仅存的历史记载来推断,最初用于渔业的灯光只是专供照明用的工作灯,在借助灯光进行作业的过程中,渔民发现某些鱼类经常在灯下聚集而开始转用于诱集鱼群。当初的集鱼灯由于兼作工作灯而总称为水上灯。水下灯的使用还是在集鱼灯利用电力以后的事情。光诱渔业的历史可以说是一部光源的变迁史。表1所示即为光源之变化。在这个表中,从用作集鱼的火把直到现代的各种强光源之间,若论其照明上的共同点,就是存在着离光源的距离上的差别,任何光源都产生明暗不同的照射部位。对光诱渔业来讲,这种明暗部位的构成有不可忽视的重要意义。     

光诱渔船集鱼灯的光照度分布及其适渔性能分析

本文通过对光诱渔船的集鱼灯水下照度实测和理论推导,对不同功率的灯光在水下的水平传播和垂直传播的光照度进行比较分析,探讨了不同功率灯光水下光照度对鲐鲹等中上层鱼类和头足类的适渔性.结果表明,灯光在水下的水平和垂直传播过程中,受媒质的影响,光照度不断减弱,但较大功率的灯光衰减较缓,在水下传播范围大,水层深.由于鲐鲹鱼类和头足类在微光下均有趋光习性,因此诱集效果较好.但是,随着水平面距离的增大,较大功率灯光的光照优势逐步减少.     

应用Monte Carlo方法计算水上集鱼灯向下辐照度在一类海水中的分布

利用叶绿素浓度、海表风速数据及集鱼灯、渔船的相关特征参数(集鱼灯的配光曲线、波谱分布、辐射通量、集鱼灯在渔船上几何位置等),采用Monte Carlo方法构造了一个计算水上集鱼灯水下辐照度分布的模型。该模型利用叶绿素浓度数据、纯海水水光学特性及其与吸收、散射系数的关系计算波束衰减系数(包括吸收系数、散射系数),利用风速数据构造毛细波面,计算该波面对光路及菲涅耳反射的影响。该模型与传统计算方法相比,有如下优点:(1) 利用叶绿素浓度数据计算波束衰减系数,并考虑了波束衰减系数的波谱特征;(2) 能提供不同水层集鱼灯向下辐照度的光谱分布;(3) 能提供渔船阴影区向下辐照度的分布;(4) 考虑了毛细波面的影响,使集鱼灯水下辐照度的计算更合理;(5) 叶绿素浓度、风速数据可由遥感获取,使模型更易应用于实际计算。模型计算结果与实测值进行了比较,相对均方根误差为37.6%,但两者之间存在显著相关性(P<0.001),文中对模型结果进行了分析。     

Optimization of LED fishing lamp allocation based on numerical modeling in Pacific saury fishery

Artificial light plays an important role in commercial light fisheries as a means to attract fish, such as the Pacific saury and squid. To gain an insight into the optimal allocation of light-emitting diode (LED) fishing lamps in the Pacific saury fishery, we present a mathematical illumination model to describe the illumination characteristics of LED modules installed at different angles. The validity of the numerical model was evaluated against the results of an optical experiment and statistical analysis. The results indicated that the agreement between observed and modeled data was good, with a mean error of 8.83%, and that the light distribution varied greatly depending on the angle. The light intensity of the LED module was distributed in the form of a series of concentric circles in the light field. With increasing angle, the maximum illumination decreased and moved away from the light source; also, the horizontally illuminated distance increased but the rate of increase gradually decreased. The illumination attenuation showed different modes between angles after passing the position at which there was maximum illumination. These results could help to further reveal the effects of LED fishing lamp allocations (e.g., installation angle, height, and interval) on underwater illumination characteristics for the optimization of the onboard lighting system and the regulation of the power of fishing lights in the future.

     

An automatic fishing machine based on acoustic conditioning

An automatic fishing machine based on acoustic conditioning was developed and tested in a reservoir. The floating fishing machine is remotely and automatically controlled to operate an underwater speaker, a feeder and underwater cameras that monitor fish behavior in real time. An open net pen installed under the system can be automatically closed to capture gathering fish. The dynamics of fish populations in the open net pen was monitored and discussed. Fish were conditioned to associate an acoustic signal with food by classical conditioning. Periodic retraining was used to reinforce the conditioned behavior of fish freely swimming in the reservoir. Fish were captured by calling them to the fishing machine using the acoustic signal and automatically closing the net pen around them: 2.5 times more fish were captured in such capture events than in control events, in which the net pen was automatically closed without calling the fish.     

渔船氨水吸收式制冷系统的建模和理论运行特性分析

根据渔船节能减排的需求,设计了一种新型的渔船氨水吸收式制冷系统,利用渔船余热实现渔船的制冰、蓄冷和工作区域供冷,解决了渔船上鱼类的保鲜和冷藏,改善船上工作环境。建立了渔船氨水吸收式制冷的热力学模型和性能评价指标,在此基础上采用序贯模块法迭代求解,实现了渔船氨水吸收式制冷系统的仿真,同时进一步研究了不同操作条件下制冷系统的运行特性,最终获得了烟气温度、流量和三通阀开度等参数变化时各用户端功率的变化规律。该系统模型可指导渔船制冷系统的功率分配,为优化渔船制冷系统的运行参数、实现低碳渔船提供理论基础。     

Catch performance and fuel consumption of LED fishing lamps in the Korea hairtail angling fishery

Angling for hairtail Trichiurus lepturus using lights is common around the Korean Peninsula. Typically, metal halide (MH) lamps are used to attract fish during the fishing process. We investigated the fishing performance and fuel consumption using light-emitting diode (LED) lamps instead of MH lamps off the coast of Jeju Island, Republic of Korea. We conducted a total of 19 fishing trips using LED lamps, at a depth of 100–145 m during the winter fishing season of 2012–2013. The catch by the LED-lamp vessel (21.6 kW) was similar to the catch by the MH-lamp vessels of similar sizes (9.77 GT) but higher light power (45–84 kW). Fuel consumption per trip for the LED-lamp vessel was 454.2 l, and fuel consumption per hour for fishing operations (excluding steaming) was 9.2–11.3 l, with an average of 10.3 l. Catch intensity, defined as catch per kW of light power (kg kW^?1) of LED-lamp vessel was significantly higher than MH-lamp vessels of all size classes. The break-even point for the vessels to install LED lamps instead of MH lamps is 109 trips per year when the fuel price is at the 2012 level of USD 0.82 l^?1. In addition, through the reduction of fuel use, CO₂ emission can be reduced by approximately 27,553.0 kg for each vessel in the fishery.     

The effect of LED lights on trap catches in Finnish inland fisheries

Trap fisheries can provide catches of high quality, and unwanted bycatch can be released with high survival. Light attraction could be an effective way of increasing trap catches, but research results are largely lacking. Experiments to test the effect of LED lights in trap-net fishing were conducted in two Finnish lakes where fishing targeted Eurasian perch Perca fluviatilis L. and roach Rutilus rutilus (L.). LED lights (white, green, red, blue and combinations) were attached inside the traps. The use of LED lights did not increase fish CPUE. Contrary to expectation, Eurasian perch catches were higher in traps without LED lights. Significant variation in CPUEs was observed, but without interaction with light treatments. The LED lights tested in this study do not increase the effectiveness of trap fishery targeting Eurasian perch and roach in Finnish lakes in the ice-free season.