海底观测网络次接驳盒硬件设计与实现

深海海底观测网络是针对深海海底探测与研究而提出的课题。在海底观测网中,为了实现对水下各种观测信息的实时采集和水下各种传感设备的控制,设计了一种基于SOC片上系统的海底观测网络次级接驳盒电路控制系统。采用模块化设计思想,构建了包括主控芯片模块、数据采集模块、电能控制模块、视频监控模块的次级接驳盒电路控制系统。试验测试结果表明,该系统能够可靠稳定地运行,为海底观测网络的长期运行提供了保证。     

海底观测网电能管理控制系统研究

海底观测网的电能是由陆地电网通过光电复合缆和接驳盒提供的,为了实现对海底观测设备电能供给状态的在线实时监测和控制,提高海底供电系统的可靠性和用能效率,设计了一套海底观测网电能管理控制系统。系统通过检测各舱体内的温度和漏水情况、电缆绝缘情况以及内外部负载的用电情况,诊断故障并采取保护措施,然后将监测数据通过光纤以太网上传至上位机,实现了岸基站控制台对系统的远程控制和管理。试验表明,该系统能够可靠稳定地运行,为海底观测网长期运行提供了保证。     

缆系海底观测网原型系统设计

针对长期、实时和原位观测深海大洋的科学需求,设计了采用10 kV直流输电和100 Mb/s光纤通信的缆系海底观测网原型系统。该系统由海底科学节点、光电复合海缆和海岸控制基站组成,其中海底科学节点包括原位化学分析仪器、动力环境监测仪器和节点接驳盒。用户从数据管理子系统实时获取科学数据,从电能监控子系统远程监控仪器状态,进行海底原位实验。多次压力实验和水池联调后,该系统在中国东海浅海试验和美国蒙特雷湾海底观测网深海并网试验中运行稳定,从海底获取了大量高分辨率的科学数据。试验证明该设计合理可行,并体现缆系海底观测网较传统海洋观测方式有较大优势。     

基于海底观测网的深海化学监测系统的设计

根据海底观测网和海洋科学仪器的特点,设计了能适用于海底观测网的深海原位化学监测系统.该系统由数据采集器以及阴离子分析仪、硝酸盐传感器、叶绿素传感器、溶解氧传感器、甲烷传感器等水下化学监测仪器组成.文中设计的数据采集器,能够与海底观测网科学仪器节点中接驳盒的标准供电和通讯接口进行连接,并能够对不同接口类型的仪器进行集成扩展.通过模拟深海环境试验以及浅海海试的验证,证明了该设计的可行性.     

模块化CC/CV变换器及其控制策略

为实现长期深海观测,并充分利用恒流输电海底观测网抵抗输电缆短路故障能力强,可靠性高,鲁棒性好等优点,设计并实现了海底观测网多模块恒流变换器。综合考虑系统体积、电能变换效率、可靠性以及输入输出电压和功率等级等多方面因素,提出采用推挽拓扑和输入串联输出并联的多模块堆叠结构的恒流转恒压电能变换系统(CC/CV)。针对恒流输电系统稳定性特性问题,分析设计用于功率补偿作用的功率平衡器,并对基于共占空比的功率平衡器控制策略进行研究。设计出在低频段具有高增益,在中频段具有足够相位裕量,在高频段能有效抑制高频干扰功能的补偿控制器以获得更佳的控制效果。在实验室环境下验证了CC/CV电能变换技术,测试结果验证了各模块间的兼容性和系统整体的可靠性,为今后研究和建设长期实用型的多节点恒流输电缆系海底观测网提供了理论依据和技术支持。     

两摆动自由度AUV水下接驳站结构方案研究

针对深海海底观测网技术发展的需求,将深海移动平台的动态、大范围观测与网络节点的静态、长期观测相结合,形成一个长期、实时的海洋环境立体观测网络,设计一种具有两个摆动自由度的水下接驳站,介绍其主体结构设计,并建立水下接驳站的拉格朗日动力学方程,分析调节重块对受到干扰后的接驳站恢复稳态的快速性的影响,同时进行仿真验证,并制作等比例缩放的接驳站样机模型进行水池试验。仿真和试验结果均表明,两自由度的水下接驳站的结构方案是可行的,可以适应不平地势、降低安装难度,并且增大调节重块的质量将有效增强接驳站的抗干扰性,减小接驳站受到干扰后偏离平衡位置的角度,加快接驳站受到干扰后的恢复到稳态的速度。     

海底观测网接驳盒电源散热机理研究

散热性能是影响海底观测网接驳盒供电电源长期运行的关键因素。根据热传导理论,分析金属耐压密封腔体内部电气热源的热耗散机理,推导出影响其热耗散性能的主要因素,得出腔内灌充绝缘导热油可大幅度改善散热效果,并利用Fluent分别对灌充气体、液体导热介质的腔体模型进行仿真验证。同时提出在油液内部留存一定体积气体的气液体结合的方式来缓解由于液体介质受热膨胀引起的压强升高问题,并进行1%、2%、5%、10%等4种不同空气体积率下的变压器油液因温升而导致压强升高的试验。得出结论:灌充绝缘导热油介质可改善水下密封腔的散热效果,但存在油液压强上升问题;气液结合方式可解决压强上升过高的问题,对于国产25#变压器油,大于8.8%的空气体积率可实现温升50℃时压强上升幅度低于0.1MPa。将该方法应用到海底观测网系统样机的2 kW电能变换器中,其试验测试结果与理论分析一致。     

消息

我初步建成新一代大洋实时观测系统国家基础研究重大项目前期研究专项“我国新一代海洋实时观测系统(ARGO)—大洋观测网试验”6月15日在杭州通过科技部组织的专家验收和国家海洋局科技司组织的成果鉴定,我国新一代大洋实时观测系统框架构建完成。ARGO是“全球海洋实时观测网”的英文缩写,如同陆地上气象站组成的天气预报观测网一样,单个的浮标相当于一个气象站,而分布广泛的ARGO浮标就组成了覆盖全球海洋的实时观测系统。项目负责人、国家海洋局第二海洋研究所许建平研究员介绍说,在科技部基础研究司、国家海洋局、中国科学院等的积极…     

基于北斗授时的CDMA通信预警浮标设计

为保护东海系统海底观测网,使海洋监测网免受人为破坏,设计一套海洋预警浮标监测系统。该警戒浮标基于北斗卫星和CDMA通信系统集成模块,能够实现实时监测、远程传输数据和岸站数据读取等功能;采用5个仓室的主体设计,配备4个独立的浮力舱;并设计航标灯、低电压报警和位移等监控报警系统。预警浮标的布放采用正五边形等距布放的预警方式,以保护网为中心,形成海上护栏,可以有效保证监测网稳定安全运行。该浮标技术采用太阳能与蓄电池互补方式供电,已在东海布放成功稳定运行半年,为海上预警技术提供参考价值。     

我初步建成新一代大洋实时观测系统

国家基础研究重大项目前期研究专项“我国新一代海洋实时观测系统（ARGO）-大洋观测网试验”6月15日在杭州通过科技部组织的专家验收和国家海洋局科技司组织的成果鉴定，我国新一代大洋实时观测系统框架构建完成。     

Minimal Realization of Linear Graph Models for Multi-physics Systems

An engineering system may consist of several different types of components,belonging to such physical"domains"as mechanical,electrical,fluid,and thermal.It is t...     

INTEGRAL EQUATION METHOD＇S APPLICATION IN HOLE-EDGE STRESS OF COMPOSITE MATERIAL PLATE WITH DIFFERENT SHAPED HOLES

The strength of composite plate with different hole-shapes is always one of the most important but complicated issues in the application of the composite material. The holes will lead to mutations and discontinuity to the structure. So the hole-edge stress concentration is always a serious phenomenon. And the phenomenon makes the structure strength decrease very quickly to form dangerous weak points. Most partial damage begins from these weak points. According to the complex variable functions theory, the accurate boundary condition of composite plate with different hole-shapes is founded by conformal mapping method to settle the boundary condition problem of complex hole-shapes. Composite plate with commonly hole-shapes in engineering is studied by several complex variable stress fimction. The boundary integral equations are founded based on exact boundary conditions. Then the exact hole-edge stress analytic solution of composite plate with rectangle holes and wing manholes is resolved. Both of offset axis loadings and its influences on the stress concentration coefficient of the hole-edge are discussed. And comparisons of different loads along various offset axis on the hole-edge stress distribution of orthotropic plate with rectangle hole or wing manhole are made. It can be concluded that hole-edge with continuous variable curvatures might help to decrease the stress concentration coefficient; and smaller angle of outer load and fiber can decrease the stress peak value.     

Non-monotonic material contrast in scanning ion and scanning electron images

30 keV Ga⁺ focused ion beam induced secondary electron (iSE) imaging was used to determine the relative contrast between several materials. The iSE signal compared from C, Si, Al, Ti, Cr, Ni, Cu, Mo, Ag, and W metal layers does not decrease with an increase in target atomic number Z₂, and shows a non-monotonic relationship between contrast and Z₂. The non-monotonic relationship is attributed to periodic fluctuations of the stopping power and sputter yield inherent to the ion–solid interactions. In addition, material contrast from electron-induced secondary electron (eSE) and backscattered electron (BSE) images using scanning electron microscopy (SEM) also shows non-monotonic contrast as a function of Z₂, following the periodic behavior of the stopping power for electron–solid interactions. A comparison of the iSE and eSE results shows similar relative contrast between the metal layers, and not complementary contrast as conventionally understood. These similarities in the contrast behavior can be attributed to similarities in the periodic and non-monotonic function defined by incident particle–solid interaction theory.     

Application of Feature Extraction through Convolution Neural Networks and SVM Classifier for Robust Grading of Apples

This paper proposes a novel grading method of apples,in an automated grading device that uses convolutional neural networks to extract the size,color,texture,an...     

分布动态载荷识别的抗噪处理

针对正交多项式频域法在用多种响应对矩形薄板进行载荷识别中抗噪性较差的问题,综合运用平均法、矩阵预处理和奇异值截断法等方法对之进行改善,并引入空间映射的思想,将该方法的应用范围拓展为复杂的模型.利用仿真算例,证实了该方法具有较好的抗噪性.     

Short-Term Relay Quality Prediction Algorithm Based on Long and Short-Term Memory

The fraction defective of semi-finished products is predicted to optimize the process of relay production lines, by which production quality and productivity ar...     

End-to-End Multiview Gesture Recognition for Autonomous Car Parking System

The use of hand gestures can be the most intuitive human-machine interaction medium.The early approaches for hand gesture recognition used device-based methods....     

基于MELTAC-N平台的核电厂安全级DCS环网研究与测试

针对工程实践中环网通讯相关问题的处理缺乏理论基础及国产化安全级DCS平台的开发缺乏成熟经验借鉴问题,对基于MELTAC-N平台核电厂安全级DCS环网的软硬件实现进行了研究。提出了安全级DCS环网双环网冗余设计、光切换开关设计等硬件设计方法,以及以RPR协议为基础,采用全数据收发策略的软件设计方法。在CPR1000安全级DCS平台上对安全级DCS环网的可靠性及实时性进行了评价,并进行了容错能力、响应时间及响应时间稳定性测试验证实验。结果表明,基于MELTAC-N平台安全级DCS环网软硬件设计具有较好的容错能力及响应时间稳定性。     

The laboratory simulation of abrasive wear

Abrasive wear has long been recognised as one of the most potentially serious tribological problems facing the operators of many types of plant and machinery; several industrial surveys have indicated that wear by abrasion can be responsible for more than 50% of unscheduled machine and plant stoppages. Locating the operating point of a tribological contact in an appropriate operational ‚map’︁ can provide a useful guide to the likely nature and origins of the surface degradation experienced in use, though care must be exercised in choosing the most suitable parameters for the axes of the plot. Laboratory testing of materials and simulations of machine contacts are carried out for a number of purposes; at one level for the very practical aims of ranking candidate materials or surface hardening treatments in order of their wear resistance, or in an attempt to predict wear lives under field conditions. More fundamentally, tests may be aimed at elucidating the essential physical mechanisms of surface damage and loss, with the longer term aim of building an analytical and predictive model of the wear process itself. In many cases, component surface damage is brought about by the ingress of hard, particulate matter into machine bearing or sealing clearances. These may be running dry although, more usually, a lubricant or service fluid is present at the interface. A number of standardised wear test geometries and procedures have been established for both two- and three-body wear situations, and these are briefly described. Although abrasive wear is often modelled as following an ‚Archard’︁ equation (i.e. a linear increase in material loss with both load and time, and an inverse dependence on specimen hardness) both industrial experience and laboratory tests of particularly lubricated contacts show that this is not always the case: increasing the hardness differential in an abrasively contaminated lubricated pair may not always reduce the rate of damage to the harder surface.     

ANGULAR DISTORTION ALLOWABLE VALUE AND ASSESS METHOD OF WELD ON COKE TOWER

A graph as the new engineering method for estimate the safety of bulging deformation of coke tower is proposed. Through stresses analysis of circumferential weld of coke tower and comparing the stresses produced by pressure with heat stress of steady state, residual stress, bending stress produced by both itself weight and wind loads, it showed that the stresses produced by pressure on the angle distortion are the main factor of equivalent stress of the combined stress. After comparing four kinds of stress controlling conditions, the relation to stress with depth of angular distortion, grade of curvature of angular distortion and half of region of angular distortion has been inferred. Graph of deformation allowable value of coke tower for different condition by angular distortion and half of region of angular distortion has been plotted. The five steps for its engineering use have been explained. The lighter the grade of curvature is, the larger of bulge allowance, may be, and the bigger of depth of angular distortion may pose too. For the coke tower with a popular structure of Dg 5 400 mm×28 mm, the result by graph is nearly more than the result of two formulas formed by other research, the error is less than 7.0%. But, the graph can be easily applied to different size of angular distortion.