Effects of tagging on migration behaviour,survival and growth of hatchery‐reared Atlantic salmon smolts

The effects of four different tagging methods (PIT, anchor T‐tag, Carlin tag and dummy radio transmitter) on survival, behaviour and growth of Atlantic salmon smolts during their downstream migration were examined in semi‐natural circular channels during a natural migration period in spring. Survival of smolts was high and tagging wounds healed well in all tagging groups. Tag loss rates were generally low, being the highest (2.5%) in the dummy radio transmitter group. Total length and body mass of the tagged and untagged smolts did not differ at the end of the experiment. Migration activity of smolts generally showed similar patterns among the treatments. However, Carlin‐tagged smolts started their migration slightly later than the PIT‐tagged fish, and smolts tagged with Carlin tag or dummy radio transmitter showed less overall migration activity than fish with PIT tag.     

基于EDA技术的自动立木整枝机无线遥控发射系统

立木整枝是优质工业用材林定向抚育的重要环节,采用自动立木整枝机是实现高效、高质量和安全可靠整枝的有效途径。本文综合运用电子电路设计及优化技术、无线遥控及通信编解码技术,创造性地研制了基于CPLD的无线数字编码抗干扰自动立木整枝机无线遥控发射系统,通过优化CPLD内部逻辑电路有效消除了逻辑竞争冒险、降低了噪声干扰,确保了系统逻辑设计的正确性。该系统具有可靠、节能、抗干扰、工作效率高等优点。本研究成果及方法为推进其他林业机械的自动化与智能化进程提供了一种有效的新思路。     

可移植的UART底层驱动构件设计

以飞思卡尔公司基于ARM Cortex-M4内核的K60系列微控制器为例,设计了一种具有较好可移植性和重用性的UART底层驱动构件．测试结果表明该构件正确而有效．     

静压储罐计量系统及其工程应用

在分析静压储罐计量系统工作原理的基础上,讨论了工程 设计中测量方案的选取及变送器的选用等问题,叙述了仪表选用安装过程。该系统由行采用高精度压力变送器和应用计算机技术,大大提高了计算精度,同时也提高了自动化管理水平。     

Do intracoelomic telemetry transmitters alter the post‐release behaviour of migratory fish?

Electronic tags have become a common tool in fish research, enhancing our understanding of how fish interact with their environment and move among different habitats, for estimating mortality and recording internal physiological states. An often‐untested assumption of electronic tagging studies is that tagged fish are representative of untagged conspecifics and thus show ‘normal’ behaviour (e.g. movement rates, swimming activity, feeding). Here, we use a unique data set for potamadromous walleye (Sander vitreus) in Lake Huron and Lake Erie tributaries to assess whether the lack of appropriate controls in electronic tagging could seriously affect behavioural data. We used fish tagged in previous years and compared their migratory behaviour during the spawning season to fish tagged in a current year at the same location. The objective of the study was to determine whether intracoelomic acoustic tag implantation altered downstream movement of walleye after spawning. Fish tagged in a given season travelled slower downstream from two river spawning sites than fish tagged in previous years. Fish tagged one or two years earlier showed no differences between each other in downstream travel time, in contrast to fish tagged in a given year. Our results support notions that standard collection and intracoelomic tagging procedures can alter short‐term behaviour (i.e. days, weeks, months), and as such, researchers should use caution when interpreting data collected over such time periods. Further, whenever possible, researchers should also explicitly evaluate post‐tagging effects on behaviour as part of their experimental objectives.     

基于MAX1464的智能压力变送器设计

本设计采用的控制核心芯片是美国Maxim公司生产的MAX1464,该芯片内含的温度传感器和ADC、DAC转换电路可使智能压力变送器的体积减小,成本降低。压力、温度信号经ADC转换成数字信号,通过对芯片的编程实现了信号的温度补偿,最终压力以4～20mA标准电流信号输出。     

TC-301型水位传感器及其在农业水利中的应用研究

我国农业水利工程中普遍采用的压力式、浮子及电容式水位传感器在泥沙大、水流急、信号远传的工程中应用时,存在一定的缺陷。结合现代计算机技术,开发精度高、适应性强的水位量测设备已经成为农业水利工程发展的必然。文中介绍的TC-301型水位传感器运用仿神经理论的思想,在农业水利工程水位的量测中取得了新的突破,应用效果良好     

3051C智能型压力变送器在管道系统中的应用

介绍了3051C智能型压力变送器的工作性能,基本工作原理以及实际操作中的应用和维修。3051C智能型压力变送器具有安装方便,维护量小,运行稳定,性能可靠等优点,通过在东营－黄岛老输油管道上一年多的应用,运行状况良好,基本上可做到免维护,大大减轻了操作人员的劳动强度,是目前管道 不可缺少的设备,同时也为进入全数学通信方式奠定了基础。     

新型玉米剥皮机的设计

玉米剥皮机是提高玉米机械化收获水平的重要装置。在分析现有剥皮机不足的基础上,进行了新型玉米剥皮机的设计和包括结构设计、原理分析、安全装置的设计、可行性分析及研究。通过对剥皮辊的螺旋式外形设计提高了剥净率。喂入口的分槽设计减少了机器被卡死的可能性,将压送器改为压伏式结构减少了制作成本且提高了压送效果。通过这些改进,提高了工作效率,降低了劳动强度。     

液压油温对涡轮流量变送器精度影响的研究

液压油温对涡轮流量变送器的测量精度有一定的影响。为了提高涡轮流量变送器测量精度,通过相应的试验,找出了液压油温度影响测量精度的规律,为液压油流量的在线测量的计算机修正提供理论依据。