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Underwater Positioning Based on an Artificial Lateral Line and a Generalized Regression Neural Network

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Journal of Bionic Engineering 2018年第5期15卷 883-893页

作者： xiande zheng Yong Zhang Mingjiang Ji Ying Liu Xin Lin Jing Qiu Guanjun Liu Science and Technology on Integrated Logistics Support Laboratory National University of Defense Technology Changsha 410073 China College of Intelligence Science National University of Defense Technology Changsha 410073 China

Taking advantage of the lateral line organ, fish can navigate, feed, and avoid predators and obstacles by sensing surrounding flow fields. The lateral line organ provides an important reference for the development of new underwater detection technology. Inspired by the lateral line organ, in this paper, for the sake of localizing the target dipole source in three-dimensional underwater space, an artificial lateral line consisting of nine underwater pressure sensors forming a cross-shaped sensor array is applied. Combined with the method of gener- alized regression neural network, which is suitable for solving nonlinear pattern recognition problems, a corresponding experimental platform has been built to sample data for training the neural network from a 12 cm by 12 cm by 24 cm cuboid space. The experimental results indicate that the cross-shaped artificial lateral line can localize the target dipole source two body-lengths away. The well- performing perceptual distance is below 13 cm away from the sensing array. Moreover, decreasing the data sampling interval and in- creasing the number of sensors utilized can help improve the positioning accuracy.

关键词： lateral line underwater positioning generalized regression neural network bionics

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声子晶体软支撑石墨烯谐振器设计与特性研究

仪器仪表学报 2023年第9期44卷 204-217页

作者：郑贤德甄嘉鹏邱静刘冠军国防科技大学智能科学学院长沙400713

航空、航天等领域对高性能传感器提出了系列迫切需求,石墨烯因其优异的机械电子学特性,有望进一步提高传感器性能,得到了广泛研究。石墨烯谐振器作为一种新的敏感单元,因其极薄的厚度而具有非常高的传感灵敏度。但目前,室温下石墨烯谐... 详细信息

航空、航天等领域对高性能传感器提出了系列迫切需求,石墨烯因其优异的机械电子学特性,有望进一步提高传感器性能,得到了广泛研究。石墨烯谐振器作为一种新的敏感单元,因其极薄的厚度而具有非常高的传感灵敏度。但目前,室温下石墨烯谐振器的抗干扰能力和稳定性普遍较差,室温下石墨烯谐振器品质因数较低成为制约石墨烯谐振器性能提升和应用的一个关键因素,提高石墨烯谐振器品质因数成为亟待研究的问题。本文通过建立石墨烯谐振器的能量耗散稀释理论模型,分析石墨烯谐振器能量耗散分布特性;在理论模型指导下,提出一种基于声子晶体软支撑结构的石墨烯谐振器能量耗散抑制新机制,开展石墨烯声子晶体谐振器优化设计、制备与特性测试分析研究,从而为提高石墨烯谐振器品质因数提供一种新的技术手段。

关键词：石墨烯谐振器声子晶体软支撑能量耗散稀释品质因数

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中职口语交际课程教学策略摭探

成才之路 2019年第19期 44-45页

作者：郑贤德福建省长乐职业中专学校

文章对中职学校口语交际课程教学策略进行研究。口语交际教学要围绕让学生更好地就业的理念,转变旧的教学思想;要围绕企业的现实需要,对教学做出相应调整;要结合不同专业选择教学内容,增强学生专业技能;要采用多种多样的教学方法,着力... 详细信息

文章对中职学校口语交际课程教学策略进行研究。口语交际教学要围绕让学生更好地就业的理念,转变旧的教学思想;要围绕企业的现实需要,对教学做出相应调整;要结合不同专业选择教学内容,增强学生专业技能;要采用多种多样的教学方法,着力打造互动课堂;要重视企业评价,真正实现课堂和企业密切结合。

关键词：中职语文口语教学教学策略口语交际能力

基于鱼侧线感知原理和深度学习的水下平动目标方向识别

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机械工程学报 2020年第12期56卷 231-239页

作者：张勇郑贤德季明江林鑫邱静刘冠军国防科技大学智能科学学院长沙410073 国防科技大学装备综合保障技术重点实验室长沙410073

鱼侧线感知原理为潜航器水下目标感知技术研究提供了一种新的思路,但由于流场模型难以准确构建,基于模型的解析方法难以准确感知水下平动目标,提出基于鱼侧线感知原理和深度学习的水下平动目标方向识别方法。通过构建偶极子源周围压力... 详细信息

鱼侧线感知原理为潜航器水下目标感知技术研究提供了一种新的思路,但由于流场模型难以准确构建,基于模型的解析方法难以准确感知水下平动目标,提出基于鱼侧线感知原理和深度学习的水下平动目标方向识别方法。通过构建偶极子源周围压力场分布模型分析鱼侧线感知目标原理,在理论上分析压力变化与偶极子源尺寸、运动参数、位置的关系,理论分析表明,流场中压力的大小与偶极子源的位置密切相关,偶极子源振动频率处的压力变化特征明显,可用于训练和识别。采用时频分析方法处理压力传感器信号并提取时频分布特征,研究表明不同平动方向产生的压力变化具有不同的时频分布特征。提出利用卷积神经网络训练压力传感器信号,进而识别水下平动目标方向。在十字形传感器阵列及试验平台上开展试验验证,试验结果表明水下平动目标方向综合识别准确率在80%以上。在无需准确建立流场模型的情况下,通过深度学习可较准确识别水下平动目标,为潜航器水下目标感知提供了一种新的技术途径。

关键词：仿生鱼侧线深度学习水下平动目标方向识别

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冻干机的能量回收

流体工程 1988年第3期 62-65页

作者：郑贤德林秀诚赵鹤皋华中工学院

本文介绍了冻干机的热回收系统并进行了热回收的能量分析。本系统在升华阶段,利用制冷压缩机冷凝器排放的热量,这意味着制冷机作为热泵运行。这样,不仅节约了升华热而且降低了压缩机的能耗及减少冷却水消耗量。

关键词：冻干机热回收能量分析制冷压缩机水汽凝结器升华热升华潜热热力学性质

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小型太阳能空调装置的性能分析

华中工学院学报 1983年第3期 21-26页

作者：陈志远王崇琦郑贤德芦壬

本文介绍了太阳能空调装置的设计、试验和性能分析的结果.文中对制冷系统的方案选择作了简略的论述,并对立式降膜吸收器的热质交换进行了理论分析,导出了吸收器的有关计算式.

关键词：吸收式制冷机组方案选择制冷系统降膜吸收器性能分析稀溶液溶液浓度太阳能空调系统热边界层温度边界层制冷机冰机制冷装置饱和温度饱和状态平板集热器制冷负荷制冷系数

Concentrations and source identification of organochlorine pesticides (OCPs) in soils from Wolong Natural Reserve

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Chinese Science Bulletin 2009年第5期54卷 743-751页

作者： zheng XiaoYan LIU xiande LIU WenJie JIANG GuiBin YANG RuiQiang State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China Chinese Research Academy of Environmental Sciences Beijing 100012 China

In order to understand the distribution profile, composition characteristics and sources of OCPs, soil samples collected from Wolong Natural Reserve (WNR) in spring and autumn in 2005 were analyzed using gas chromatography coupled with electron capture detector (GC-ECD). Results showed that all OCPs concentrations were in the range of 10?2 ng/g―10?1 ng/g, representing the background level in those remote sites. Generally, their concentrations were slightly higher in spring than in autumn, which could be explained by OCPs: 1) may be released to soil from snow-melting water in spring; 2) partially evaporate into air from soil due to high temperature and intense radiation in summer and 3) can be relatively high degradation rate in summer. There were notable differences of OCPs seasonal variations between samples from alpine meadow and those from under-treeline. This phenomenon was related to physical-chemical properties of OCPs and vegetation coverage. For alpine meadow soils, levels of OCPs were increased with increasing altitudinal gradient, which was associated with enhanced scav-enging efficiency of wet precipitation. Composition characteristics of OCPs in soils were similar to those of air samples, which was distinct from those of typical contaminated soils, indicating that OCPs in WNR soils were mainly from atmospheric transport.

关键词：有机氯杀虫剂土壤污染组成特性季节性变化来源鉴定

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电力线杆塔监测中点云数据的应用

科学技术创新 2024年第1期 11-14页

作者：徐郑王维坤童贤德丁思明魏茂荣安徽送变电工程有限公司安徽合肥

为精准高质量三维激光点云实施电力线杆塔变形监测质量,需对电力线杆塔所处的输电线路走廊进行分析,从数据采集、点云预处理、特征图计算三个方面讨论电力线杆塔三维激光点云数据的运用细节,完成点云数据处理后进一步展开电力线杆塔三... 详细信息

为精准高质量三维激光点云实施电力线杆塔变形监测质量,需对电力线杆塔所处的输电线路走廊进行分析,从数据采集、点云预处理、特征图计算三个方面讨论电力线杆塔三维激光点云数据的运用细节,完成点云数据处理后进一步展开电力线杆塔三维激光点云变形监测,了解电力线杆塔变形情况。

关键词：三维激光点云电力线杆塔变形监测

Barometric altimetry system as virtual constellation applied in CAPS

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Science China(Physics,Mechanics & Astronomy) 2009年第3期52卷 376-383页

作者： AI GuoXiang SHENG PeiXuan DU JinLin zheng YongGuang CAI xiande WU HaiTao HU YongHui HUA Yu LI XiaoHui National Astronomical Observatories Chinese Academy of SciencesBeijing 100012China School of Physics Peking UniversityBeijing 100871China National Time Service Center Chinese Academy of SciencesXi’an 710600China

This work describes the barometric altimetry as virtual constellation applied to the Chinese Area Positioning System (CAPS), which uses the transponders of communication satellites to transfer navigation messages to users. Barometric altimetry depends on the relationship of air pressure varying with altitude in the Earth’s atmosphere. Once the air pressure at a location is measured the site altitude can be found. This method is able to enhance and improve the availability of three-dimensional positioning. The difficulty is that the relation between barometric pressure and altitude is variable in different areas and under various weather conditions. Hence, in order to obtain higher accuracy, we need to acquire the real-time air pressure corresponding to an altimetric region’s reference height. On the other hand, the altimetry method will be applied to satellite navigation system, but the greatest difficulty lies in how to get the real-time air pressure value at the reference height in the broad areas overlaid by satellite navigation. We propose an innovational method to solve this problem. It is to collect the real-time air pressures and temperatures of the 1860 known-altitude weather observatories over China and around via satellite communication and to carry out time extrapolation forecast uniformly. To reduce data quantity, we first partition the data and encode them and then broadcast these information via navigation message to CAPS users’ receivers. Upon the interpolations being done in receivers, the reference air pressure and temperature at the receiver’s nearby place is derived. Lastly, combing with the receiver-observed real air pressure and temperature, the site’s altitude can be determined. The work is presented in the following aspects: the calculation principle, formulae, data collection, encoding, prediction, interpolation method, navigation message transmission together with errors causes and analyses. The advantages and shortcomings of the technique a

关键词： CAPS system navigation and positioning barometric altimetry bound solution