3D Ice Shape Description Method Based on BLSOM Neural Network

When checking the ice shape calculation software,its accuracy is judged based on the proximity between the calculated ice shape and the typical test ice shape.Therefore,determining the typical test ice shape becomes the key task of the icing wind tunnel tests.In the icing wind tunnel test of the tail wing model of a large amphibious aircraft,in order to obtain accurate typical test ice shape,the Romer Absolute Scanner is used to obtain the 3D point cloud data of the ice shape on the tail wing model.Then,the batch-learning self-organizing map(BLSOM)neural network is used to obtain the 2D average ice shape along the model direction based on the 3D point cloud data of the ice shape,while its tolerance band is calculated using the probabilistic statistical method.The results show that the combination of 2D average ice shape and its tolerance band can represent the 3D characteristics of the test ice shape effectively,which can be used as the typical test ice shape for comparative analysis with the calculated ice shape.

IC-CPD测试系统设计与研究

电动汽车充电模式2属于交流慢充模式,其能够连接传统家用插座和车辆,便于携带,使用灵活。充电模式2必须配备缆上控制与保护装置(IC-CPD)以保证充电安全。在IC-CPD出厂前必须经过严格的测试,以满足安全使用条件。基于IC-CPD测试的重要性,分析了IC-CPD主要功能及内部结构;设计开发了一种能模拟电动汽车充电模式2导引过程,进行CP信号测试和辅助充电网络上继电器关断测试的IC-CPD测试设备;并详细给出了该测试设备的硬件电路设计及与IC-CPD进行测试的具体过程。

Model Test Study on Ice-Induced Vibrations of Compliant Multi-Cone Structures

For the study on the ice-induced vibration of a compliant mono-cone structure,a series of model tests were performed from 2004 to 2006.In these tests,the ice sheet before the compliant conical structure was found to be failed in two-time breaking.Based on this important finding,model tests study of the ice force on a compliant multi-cone structure were performed from 2006 to 2007.In these tests,the ice sheet broke before each single cone non-simultaneously.The exciting energy of the total ice force was found to be in a wide range of frequencies,and the structure can be easily excited with nonlinear resonance.

Model Test Study on Ice Induced Vibration of A Compliant Conical Structure

The problem of ice induced vibration is common to ocean engineering of cold region countries. To study the ice induced vibration of a compliant conical structure, a series of model tests have been performed and some breakthrough progresses made. The ice sheet before the compliant conical structure is found to fail by two-time breaking in the tests. The process of two-time breaking behaves in two modes, and the general control of the ice and structural conditions determine the mode in which the ice force would behave. Two dynamic ice force functions are established respectively for the two modes of two-time breaking process in this paper. The numerical simulation results are in good agreement with the measured results, indicating that the dynamic ice force functions given in this paper can fully reflect the real situation of the dynamic ice force on a compliant conical structure.

Establishmen and vertification of an improved similitude law for dynamic ice force model test

To study the similitude laws for dynamic ice force model test which is a hot problem in ice mechanics.In this paper,a new modified similitude law for dynamic ice force model test is proposed based on ice-induced virbration theory and two reasonable assumptions.And the new law is vertified with an ice-induced pier virbration example.The numerical calculation results show that,firstly,the error of frequency factor between test value and theory value is small as well as that of displacement and velocity;Secondly,the time scale completely meet the similitude relation,the waveforms anastomotic well,and the phenomenon of offset and omit do not occur;Thirdly,as the damping ratio between prototype and model is nearly equal,the improved similitude law will still be applied.Therefore,the new modified similitude law is feasible to study dynamic ice force model test and can provide reference for the ice mechanics.

基于FPGA的IC自动测试系统设计

基于FPGA技术设计了一种IC自动测试系统,通过总线通信的优化实现了板卡的柔性化组合与拓展。系统能自动识别槽位上的模块型号,并按系统CONFIG要求分配资源。实践表明,该系统可满足数字类IC和模拟类IC的量产测试需求,适用于IC的芯片验证测试和出厂成品测试;运行平稳、安全可靠,为集成电路测试设备的国产化、数字化和网络化提供了切实可行的解决方案。

STUDY ON MAXIMUM SPECIFIC SLUDGE ACTIVITY OF DIFFERENT ANAEROBIC GRANULAR SLUDGE BY BATCH TESTS

The maximum specific sludge activity of granular sludge from large scale UASB, IC and Biobed anaerobic reactors were investigated by batch tests. The limitation factors related to maximum specific sludge activity (diffusion, substrate sort, substrate concentration and granular size) were studied. The general principle and procedure for the precise measurement of maximum specific sludge activity were suggested. The potential capacity of loading rate of the IC and Biobed anaerobic reactors were analyzed and compared by use of the batch tests results.

Model Test Study of Dynamic Ice Force on Compliant Conical Structures

To study ice-induced vibration of a compliant conical structure, a series of model tests were performed from 2004 to 2005. In the tests, the ice sheet before the compliant conical structure was found to fail in two-time breaking. From 2005 to 2006, this type of ice failure was studied through more groups of tests. The tests show that two-time breaking is the typical failure of ice before steep conical structures, and is controlled by other factors at the same time, such as ice speed and the angle of the cone.

Wind Tunnel Test and Numerical Computation on Ice Accretion on Blade Airfoil for Straight-bladed VAWT

To invest the condition of ice accretion on the blade used for straight-bladed vertical axis wind turbine （SB-VAWT）, wind tunnel tests were carried out on a blade with NACA0015 airfoil by using a small simple icing wind tunnel. Tests were carried out at some typical attack angles under different wind speeds and flow discharges of a water spray with wind. The icing shape and area on blade surface were recorded and measured, Then the numerical computation was carded out to calculate the lift and drag coefficients of the blade before and after ice accretion according to the experiment result, the effect of icing on the aerodynamic characteristics of blade were discussed.

风力发电机叶片防除冰涂层(二):温升数值计算及防除冰性能

针对电热超疏水涂层覆冰过程中表现出的三类不同冰层形貌,该文建立了电加热融冰数值计算模型,并对仿真计算结果进行了相应的试验验证,验证结果与仿真结果基本一致,该模型能有效模拟融冰过程和温度分布。临界融冰功率的计算结果表明,电热超疏水涂层融冰所需功率大于非超疏水电热涂层,尤其在乳突状冰层出现后,融冰功率将大幅增加。电热超疏水涂层防冰试验结果表明,在雨凇覆冰环境中,超疏水性能单独作用时,叶片在覆冰前期能延缓覆冰;电热性能与超疏水性能共同作用时,叶片无覆冰形成。电热超疏水涂层用于风力发电机防覆冰具有较好的效果,但用于覆冰后的融冰时将需要更多的能量。

基于MicroBlaze的以太网卡芯片功能测试方法

对于数字芯片或数模混合芯片的功能测试,传统的在FPGA上以硬件描述语言编程和测试的过程中,无法产出可移植性较强的C程序。而使用SoC或MCU作为主控单元,测试程序开发过程中的信号测量、电路更改,不如在FPGA上方便。针对一款以太网卡芯片的功能测试任务,基于FPGA使用软处理器核MicroBlaze作为CPU,以太网卡芯片作为外设,通过软硬件协同设计,搭建了灵活的开发与测试环境。在此开发和测试环境中,实现了以太网卡芯片的驱动程序,并完成了以太网卡芯片的功能测试。实验结果表明,本设计和实践可作为类似的数字芯片测试工作的参考。

基于旋转圆柱三电极阵列的覆冰测量方法

覆冰严重会影响电网安全稳定运行,输配电装备的覆冰监测是电网冰灾防御的前提。为此,基于冰层的电容效应提出一种旋转圆柱三电极阵列覆冰测量方法。首先,推导电容值与覆冰厚度计算公式,从理论上说明该方法的可行性;其次,建立圆柱三电极阵列有限元模型并对其结构参数进行有限元数值计算;再次,以信号强度、灵敏度与穿透深度为评价指标对圆柱三电极阵列选取合适参数;最后,在野外自然环境下对旋转圆柱三电极阵列覆冰测量装置进行试验。仿真和试验结果表明,在穿透深度以内,旋转圆柱三电极阵列能够较为准确地测量覆冰厚度、分辨覆冰类型。在雨凇、混合凇覆冰条件下,覆冰电容值平均误差最大为4.83%,能够满足覆冰厚度的测量要求。该文为输配电装备覆冰监测提供了一种新型装置与测量方法,未来有望应用于架空线路覆冰在线监测。

Improved significance testing of wavelet power spectrum near data boundaries as applied to polar research

When one applies the wavelet transform to analyze finite-length time series, discontinuities at the data boundaries will distort its wavelet power spectrum in some regions which are defined as a wavelength-dependent cone of influence （COI）. In the COI, significance tests are unreliable. At the same time, as many time series are short and noisy, the COI is a serious limitation in wavelet analysis of time series. In this paper, we will give a method to reduce boundary effects and discover significant frequencies in the COI. After that, we will apply our method to analyze Greenland winter temperature and Baltic sea ice. The new method makes use of line removal and odd extension of the time series. This causes the derivative of the series to be continuous （unlike the case for other padding methods）. This will give the most reasonable padding methodology if the time series being analyzed has red noise characteristics.

一种基于分压电路的绑定后TSV测试方法

对硅通孔(Through Silicon Via,TSV)进行绑定后测试可以有效地提升三维集成电路的性能和良率。现有的测试方法虽然对于开路和桥接故障的测试能力较高,但是对于泄漏故障的测试效果较差,并且所需的总测试时间较长。对此,提出了一种基于分压电路的TSV绑定后测试方法。该方法设计了一种分压电路,进行泄漏故障测试时可以形成一条无分支的电流路径,有效提高了对泄漏故障的测试能力。此外,该方法测试开路故障和泄漏故障时的电流路径不会相互干扰,可以同时测试相邻TSV的开路故障和泄漏故障。实验结果表明,该方法可以测试10 kΩ以下的弱泄漏故障,并且在工艺偏差下依然能够保持较高的测试能力。相比同类测试方法,该方法所需面积开销更小,所需总测试时间更少。

基于改进SHRP融冰试验的氯盐融雪剂性能研究

氯盐融雪剂因其融冰除雪性能优异、价格低廉、易于获取而得到广泛应用。为探究氯盐融雪剂的温度适用性不同、标准不统一、撒布方式粗略等问题,该文通过改进的SHRP融冰试验,分析了温度、固液态及撒布方式对NaCl、CaCl_(2)、MgCl_(2) 3种常用氯盐融雪剂除冰性能的影响。试验结果表明:氯盐融雪剂的除冰性能对温度具有显著的敏感性;MgCl_(2)、CaCl_(2)两种融雪剂在融化过程中存在“放热”效应;同种氯盐融雪剂在固态下的融冰效率高于液态下的;同种氯盐融雪剂在不同撒布方式下融冰效率不同,其中,在线性撒布下除冰能力最强。根据试验结果,建议使用固态线性撒布的方式,并根据环境温度选择适宜的融雪剂。

基于有限元模型的IC卡芯片受力分析研究

在智能卡三轮测试中,失效表现为芯片受损,本文基于有限元模型来研究智能IC卡(Integrated circuit card)芯片受力分析与强度提升方法,针对其结构尺寸参数变化时对芯片的机械强度影响做了相关有限元仿真,分析芯片的受力情况,从芯片大小、芯片厚度、芯片偏转角度、EMC层厚度、PVC厚度、Lead frame厚度、芯片粘接胶厚七个因素,对比了IC卡单因素尺寸参数变化对芯片应力的影响,并依据正交设计表分析IC卡的七个因素的参数变化时芯片的受力情况,得到EMC层厚度、Lead frame和PVC卡片厚度的变化对芯片承受的最大应力影响显著,且随着这三个部件厚度的增加芯片所受最大应力减小的结论,为有效提升IC卡芯片的机械强度提供了方法。

基于含冰量的冻结砂土-混凝土接触面蠕变特性

保证高含冰量冻土区桩基础的长期稳定性是多年冻土区桥梁桩基础安全服役中的关键问题,为研究含冰量对冻土-混凝土接触面蠕变特性的影响,采用自行研制的大型蠕变剪切仪,在−2℃条件下开展含冰量为6%、12%、16%、23%、36%、60%、80%的冻结砂土与混凝土接触面蠕变试验.试验结果表明:在恒定的剪应力作用下,除含冰量为6%试样出现加速蠕变外,其他试样仅出现衰减蠕变及稳定蠕变2个阶段;随含冰量的增大,试样黏性变形占比增大,含冰量为80%试样的黏性变形超过总变形量的80%;稳定蠕变速率受到干密度及含冰量的综合影响,含冰量为16%时稳定蠕变速率最小;Burgers黏弹性模型能较好地模拟高含冰量冻结砂土-混凝土接触面蠕变曲线;随着含冰量的增大,初始剪切模量和稳定蠕变阶段黏滞系数先增大后减小,初始蠕变阶段的渐进剪切模量呈幂函数减小,初始蠕变阶段黏滞系数呈幂函数增大.

覆冰厚度对气动脉冲除冰效果影响的数值仿真与试验验证

叶片结冰影响风力发电机的安全稳定运行,现有的叶片热力除冰、涂料防冰技术分别存在能耗高、耐候性差等问题,均无法大面积推广应用。受飞机机翼气囊除冰方法启发,该文提出一种新结构式的气动脉冲除冰方法。利用Abaqus商业软件对该方法的简化模型进行除冰过程的数值仿真,对比分析了不同脉冲充气气压下覆冰厚度对除冰效果的影响。同时,通过人工覆冰与除冰试验,对仿真结果进行验证。仿真与试验结果表明:在低充气气压下,冰层越薄越容易破碎脱落,覆冰厚度的增加有利于提升低充气气压下的脱冰率;在相同充气气压下,冰层厚度的增加可以降低结构表面形变。

3D-SOI像素芯片逻辑层的设计与实现

环形正负电子对撞机(CEPC)实验对顶点探测器的空间分辨率提出了极为苛刻的要求。SOI像素传感器芯片CPV-4使用了3D堆叠技术来满足CEPC需要的高空间分辨率。本文主要研究在3DSOI技术下CPV-4的逻辑层电路设计与验证。逻辑层作为CPV-43D芯片的上层部分包含粒子击中信息的存储和读出功能,采用了紧凑的像素逻辑设计和高效的优先级编码读出逻辑设计。测试系统基于IPBUS协议实现了逻辑交互、数据传输和用户界面的软硬件功能,同时开发了模仿逻辑层功能和接口的仿真器模块。通过对仿真器模块、单独的上层芯片以及3D堆叠后的片上逻辑层进行对比测试,完整验证了片上逻辑层的电路功能,并证明了3D堆叠的键合、减薄和顶层金属化等工艺步骤对片上逻辑层没有不利影响。3D-SOI像素芯片的逻辑电路设计和3D堆叠技术研发取得了初步进展。