蟹笼渔船完整稳性衡准研究

以6.60m蟹笼渔船为例,采用静力学方法分析蟹笼船在横倾状态下的受力情况,通过改变蟹笼装载区和活水池等的布置方案,分析比较了其对渔船稳性产生的影响,并探讨提高渔船完整稳性的一些措施。     

舟山蟹笼渔具渔法

渔笼是一种低能耗、少劳力、不破坏生态环境的被动性渔具渔法。它不受船舶吨位、马力限制,种类渔船均可用渔笼作为主业或付业从事捕劳生产。渔笼在欧美、澳大利亚、新西兰、台湾等地区相当流行,主要捕劳龙虾、鲷类等高贵鱼种。浙江省舟山渔区1992年上半年少数渔船开始用蟹笼捕捞三疣梭子蟹。由于梭子蟹资源丰富、身价较高(用于出口),加上蟹笼生产成本低、投入少、劳力     

蟹笼作业的渔具渔法试验报告

渔笼是一种低能耗、少劳力、渔获价位高,不破坏生态环境的被动性渔具渔法,它不受船舶吨位、马力限制,各类渔船均可用蟹笼作为主业或付业从事捕捞生产,渔笼在欧美、澳大利亚、新西兰、南朝鲜、台湾等地区相当流行。 福建省平潭县蟹笼作业是九十年代初从台湾引进的,使用初期,由于船小,携带笼具少,多系在沿岸传统渔场作业,因而形不成规模效益。1993—1994年福建省闽中渔场指挥     

蟹笼捕捞技术

蟹笼是一种低能耗、少劳力、渔获价位高、不破坏生态环境的渔具渔法,它不受船舶吨位、功率限制,各类渔船均可用蟹笼作为主业或副业从事捕捞生产,由于其主捕蟹类,渔获选择性强,有利于近海渔业资源、种群结构调整以及合理利用、开发、保护鱼类资源,蟹笼捕捞作业因投资省、见效快、效益高、捕捞操作简单易学,而深受群众的喜爱。现将蟹笼捕捞技术总结如下。一、笼具规格1、蟹笼框架:笼具为铁骨网笼,圆柱形,直径60cm,高24cm。铁质圆圈2个,由2根直径12mm的圆钢弯成,接处焊牢固。再用直径为8mm的圆钢割成6根长度为24cm和2根长度为61cm的短圆钢。将2…     

海洋集体渔业在机帆化道路上前进

我国海洋集体渔业使用机帆渔船,已有十一年的历史了.机帆渔船是在海洋集体渔业经济不断巩固与壮大的同时迅速发展起来的,并已取得了重大的成就.旧中国,在帝国主义、官僚资本和封建势力的反动统治下,渔民遭受重重的压迫和摧残,生产、生活十分困难,只靠破旧的风帆渔船作业,生产技术落后,产量极低,渔业生产陷入奄奄一息的状况,无力实现技术改造,更谈不上实现机械化.解放后,摆在广大渔民面前的重大任务之一,是如何改变技术装备落后的状态,尽快地实行渔业技术改造,实现现代化、机械化的生产.而渔船机动化又是技术改造的根本环节.这是更快地提高劳动生产效率,改变生产、生活面貌的关键.     

闽南渔场蟹笼作业渔获组成和主要种类

蟹笼是用饵料引诱捕捞对象入笼而捕获蟹类等渔获物的一种被动性渔具,在海洋捕捞分类上属笼壶类渔具。蟹笼作业具有能耗低、效率高、渔获价位高、渔具简单、操作方便、对渔民适应性较强等特点,在福建省有一定的规模。国内对蟹笼的报道也较集中在捕捞技术、选择性、渔获试验分析等方面。20世纪90年代中期在闽中海域做过蟹笼作业渔具渔法方面的研究报道。对于蟹笼作业渔获组成,仅见洪明进等人有过简单报道,缺乏对其优势种的报道。据“福建省渔业统计年鉴（2009）”,     

捕捞乌贼的设备

为实现捕捞乌贼的自动化，提高捕捞效率之目的，苏联国家渔船设计院改制了一种捕捞乌贼的设备，此设备与吸鱼泵配套使用，其结构主要由18个零部件所组成(详见图)。     

渔业动态

日本目前通过民间渔业协定在朝鲜民主主义共和国200海里经济水域作业的渔船有:鱿鱼钓渔船和蟹笼渔业渔船。关于日朝的狭鳕贸易问题,早在1978年的日朝民间渔业协定谈判时提出来的。当时朝鲜方面提出,在朝鲜200海里水域内作业的日本渔船,可不交付捕鱼税,但需要向朝方购卖一定数量的狭鳕。1980年时这个问题再次提出,但后因1983年起连续二年日朝民间渔业协定因故临时中断而搁置了下来。到1985年随着日朝民间渔业协定的恢复,日朝狭鳕     

蟹笼作业和蟹笼起拔设备

1　蟹笼捕捞作业1 .1　蟹笼捕捞作业概况浙江省的捕蟹作业历来以流网和拖网捕捞梭子蟹为主。浙南地区也有延绳钓和刺网捕蟹等作业方式。直至 80年代引进蟹笼捕捞技术 ,有关科研院校对蟹笼的结构作了一些改进而提高了捕蟹产量。蟹笼捕捞逐步从舟山的岱山、嵊泗、普陀向省内宁波、象山、温台地区推广。并建造了专用的钢质蟹笼捕捞船 ,从一条船装数百只蟹笼 ,发展到今天配备蟹笼起拔设备 ,每条船能带蟹笼三、四千只 ,捕捞水平和产量都有了很大的提高。特别是舟山嵊泗绿华乡 ,在发展蟹笼作业的同时 ,学习国外先进经验 ,与有关厂家共同开发成功液…     

基于轴功率测量的渔船动力装置优化配置研究

渔船船、机、桨不匹配现象较为普遍,不但降低了渔船的经济效率,而且给渔船的安全生产带来隐患.轴功率是反映船舶柴油机及其动力装置最重要的性能参数之一.通过对渔船主机轴功率进行实船测试,不仅可以发现主机的技术状况是否良好,而且可以判断船、机、桨的匹配情况,为船厂和用户提供可靠的试验数据,以便及时进行修理或调整,保证主机和整个船舶始终处于良好的技术状态.本文结合船舶轴功率-转速特性图,对实现渔船动力装置优化配置进行了理论分析,结论有利于选择最佳工况、提高整个动力装置的经济性.     

基于PLC的深水网箱自动投饵系统

为提高深水网箱养殖投饵的自动化和工业化水平,设计并开发出适合深水网箱养殖投饵管理的自动投饵系统。该系统采用PLC为控制核心,继电接触器控制各个设备的启停,实现精确投饵。文章介绍了系统的工作原理和设计框架,阐述了系统控制电路、系统工作流程与PLC硬件结构,设计了系统关键设备控制方案并编写了相关控制程序。检测结果表明,在投饵输送距离为300 m时,投饵量为1 200 kg.h-1,系统风量为5.56 m3.m in-1,系统风压为49 kPa;吨料能耗最大为8.4 kW.h.t-1（平均为5.0 kW.h.t-1）,投饵破碎率小于0.7%,喷投距离达11.3 m;系统可实现动态定时、定点和定量投喂饲料,完全满足深水网箱集群养殖的要求。     

基于MCGS的深水网箱自动投饵远程控制系统的设计

为提高深水网箱养殖投饵的自动化和工业化水平,设计并开发出适合深水网箱养殖投饵管理的自动控制系统。该自动投饵控制系统基于MCGS组态软件进行二次开发,采用PLC为控制核心,应用计算机与PLC进行通讯。介绍了深水网箱自动投饵系统的工作原理和系统设计框架,阐述了PLC控制系统的工作流程和程序设计,说明了基于MCGS组态软件的系统组态过程。运行试验的结果表明,系统具有性能稳定、可靠性高、人机界面友好、操作便捷等特点,实现了投饵控制、动画显示、系统状态监控、权限管理、历史数据输出、打印等功能,可以满足深水网箱集约化养殖精确投饵操作和管理等各项要求。     

深水网箱需求式自动投饵装置的初步研究

深水网箱的自动化控制是我国网箱事业发展的趋势。本文对现有投饵装置进行了分析，在此基础上，设计了一种需求式自动投饵装置，旨在提高投饵效果。网箱养殖鱼群经过驯化，有求食需求时自动触动水下金属管，并通过传感器启动下料机构。该装置通过可编程控制器(PLC)实现投饵过程控制，其优点是能根据养殖鱼类需求，实时投饵，饵料利用率高，水体污染少，满足当前深水网箱自动化发展的需求。     

Development and comparative test of squid liver artificial bait for tuna longline

ABSTRACT:   We have been developing an artificial bait for longline tuna fishing using the liver of the Japanese common squid Todarodes pacificus , a waste product of the squid fisheries industry, as the primary component. Three control test operations using the artificial bait and natural squid were conducted during January 1998, 1999 and 2000. During these operations, we compared the angling performance of the artificial bait with that of the natural squid. Some tuna was caught using the artificial bait; however, the hooking ratio for the artificial bait was less than that for the natural baits. Despite this, there was no significant difference between the hooking ratio by artificial bait and natural squid. In addition, species selectivity in the by-catch, a characteristic particular to this artificial bait, was observed. In the present paper, we discuss the hooking ratio and the reduction in by-catch of the artificial bait compared with natural bait.     

Conservation of small hairtail <Emphasis Type="Italic">Trichiurus japonicas</Emphasis> by using hooks with large artificial bait: effect on the trolling line fishery

Overfishing has reduced the stock of hairtail Trichiurus japonicus around the Bungo Channel, Japan. To determine whether using larger bait in the trolling line fishery could avoid catching small/undersize hairtail, we developed and trialled a new large artificial bait (a soft plastic bait, 6 inches long). A traditional lure with natural bait (type-1), a new lure of the new artificial bait hook without natural bait (type-2), and a new lure with natural bait (type-3) were tested in fishing operations around the Bungo Channel. Compared with type-1, type-2 and type-3 caught fewer undersized and immature female individuals. The number of fish caught, yield, and composition of commercial size grades per recruitment were calculated from field data for each lure and compared. The catch sizes (number of fish per recruitment) were smaller for type-2 and type-3 than for type-1, but yield per recruitment was higher for type-3 than for type-1. Compared with type-1, type-2 and type-3 caught more large individuals, which are more valuable. The newly developed artificial bait conserves hairtail stocks by targeting larger fish, which is economically beneficial for the hairtail trolling line fishery.     

Deep hooking,landing success and gear loss using inline and offset circle and J hooks when bait fishing for white sturgeon

The issue of deep hooking is of concern in white sturgeon, Acipenser transmontanus Richardson, fisheries because nearly all anglers use bait with a stationary presentation on the river bottom to catch them, and bait fishing is often associated with higher instances of deep hooking and hooking mortality. Deep hooking rates, landing success and catch rates were investigated for anglers bait fishing for white sturgeon using circle and J hooks with inline and offset alignments fished with both active and passive hook‐setting methods. Anglers hooked 578 white sturgeon and landed 508 fish, ranging in size from 60 to 316 cm total length (mean = 137 cm). Deep hooking rates averaged 0.6% and did not differ between hook types, hook alignments or hook‐setting methods. Landing success (the proportion of hooked sturgeon that were successfully landed) and catch rates were also equivalent between hook types, hook alignments and hook‐setting methods; landing success averaged 88% and catch rates averaged 0.27 fish/hr. Results of this study indicate that deep hooking is rare when angling for white sturgeon using standard bait‐fishing gear regardless of hook‐setting method or whether circle or J hooks were used; regulations restricting hook type in sturgeon bait fisheries are therefore unwarranted.     

网箱养殖智能投饲监控系统的设计

针对浑水海域网箱养殖中的投饲量控制问题,提出了一种采用回声探测方法进行智能投饲监控的系统原理及软硬件设计。在网箱底部安装一套收发合置的回声探测声纳,监测通过网箱饲料反射的声信号能量值,将其作为反馈量来调整饲料流量,使得过剩饲料维持在预设量,以实现智能饲量控制。为简化投饲监控系统并降低成本,可采取1套回声探测系统同时监控4个网箱的设计,并将各个监控节点组成WLAN后接入公网,以实现大型网箱养殖场的远程智能投饲监控。     

Automatic submerging and surfacing performances of model submersible fish cage system operated by air control

An automatic, submersible fish cage system using air control was developed and a set of model experiments were conducted to examine the automatic submerging characteristics of the cage. The components of the fish cage consist of a rigid frame assembly with 6 variable ballast tanks and 6 fixed ballast tanks. The variable ballast tanks were used to change the buoyancy characteristics of the system by air control so that the fish cage can either be placed at the surface or submerged. The cage is free to move vertically within a water column by adjusting the weight and the buoyancy with an air control system. The model of this system, with dimensions of 2.20 m in diameter and length and 1.04 m in net cage depth, was constructed to be 1/10 the size of the full-scale system. In the model experiments, the submerging and surfacing characteristics of the cage were regulated with measurements from a water-pressure gauge and a gyroscope incorporated into the automatic control system. Model tests were performed in a still water tank and a large wave tank to develop the algorithm required to control the cage system and to verify the ability of the automatic submersion mechanism to function. The control system was designed so that when the variable ballast tanks were flooded with water, the model descended. To raise the system, compressed air is injected into the tanks by opening the main evacuation valve on the manifold. After the required amount of compressed air is supplied, the main evacuation valves can be shut and as a result, the fish cage becomes buoyant. Measured performance results in a still water tank are then compared with calculations from a previously developed numerical technique. The submerging and surfacing characteristics of the fish cage were relatively similar to the measurements obtained with the physical model experiments using air control. The cage was submerged to a target depth when incidence wave heights were higher than the critical wave height and raised when little wave actions were detected in a wave tank. On the other hand, the cage was placed at the surface when incidence wave heights were the same as the critical wave height or lower.     

The use of European river lamprey as bait by the UK coarse predator angling community

Recreational fishing is a commonplace leisure activity within the developed world but can generate tension when activities conflict with conservation agendas. A potential conflict arises over the use of European river lamprey, Lampetra fluviatilis (L.), a protected species, by UK coarse (freshwater non-salmonid) predator anglers. This study used geographically stratified interviews with 69 predator anglers to explore attitudes towards the use of lamprey as bait, their conservation status and knowledge of biosecurity regulations. Most participants used lamprey as bait to some degree and agreed that, if threatened by exploitation, a ban on their use as angling bait should be implemented. Ordinal regression analysis indicated the presence of a subset of anglers who value lamprey as bait more than others and may oppose conservation efforts. The benefits of the potential establishment of bait certification schemes are also considered.