从2001年PITTCON看微全分析系统的发展

根据2001年匹兹堡会议的报告和展品较全面和系统地评述了微型全分析系统（μ－TAS）的最新发展情况。     

医用μTAS微型葡萄糖生物传感器中的微加工技术

研制了一种基于IDA薄膜电极的微型葡萄糖生物传感器，结合该传感器IDA薄膜电极的加工，介绍了目前μTAS加工中的微加工技术。     

微流控芯片光学检测系统集成化新进展

微流控芯片是微全分析系统(μTAS)中当前最活跃的领域和发展前沿。目前人们在微流控芯片的研究中已经取得了很大的进展,研制出了多种微型化、集成化的芯片。相比之下,与微流控芯片配套的高灵敏度微型光学检测系统的研制却相对落后。介绍了分别基于CMOS、垂直腔面发射激光器(VCSEL)和微型雪崩光电二极管(μAPD)来实现光学检测系统与微流控芯片集成化的方法。     

以太网TSN报文延时仿真研究

随着汽车智能网联化进程的加速，传统CAN/CANFD通信已经不能满足高效数据传输的带宽和实时性需求。TSN（时间敏感型网络，Time Sensitive Network）作为新一代以太网技术，可以解决车载网络对于信息低延迟，高速率的传输问题，可以保证信息的实时性传输引起车载网络工程师的关注。本文采用仿真和实验相结合的方式，验证了SP(Strict Priority)、TAS(Time Aware Shaper)对于时间敏感参数传输延迟的影响。结果显示，在各类负载工况下，相对于无QoS机制，采用SP机制可以显著降低时间敏感参数的传输延迟；采用CBS(Credit based Shaper)通过队列信用值管理，TAS将时间敏感参数的传输延迟控制在200μs以内，效果优于SP机制。研究结果为车载TSN网络设计提供了必要的理论支持。     

基于苦味受体表达的多组织细胞传感器及其应用

非口腔组织中的苦味受体(TAS2Rs)可能成为相关疾病治疗的新靶点。 该研究将表达有 TAS2Rs 的细胞作为敏感元 件,根据其生理特性与不同的传感器耦合,探究了味觉受体异位表达及其在个性化药物筛选中的应用,构建了针对不同疾病模 型的个性化药物筛选平台。 首先,基于细胞阻抗传感器以及内源性表达 TAS2R38 受体的结肠癌细胞,开发了异硫氰酸酯类物 质特异性药物筛选平台,求得苯硫脲的 EC50 为 157. 6 μM;其次,结合微电极阵列检测系统,探究了 TAS2Rs 激动剂地芬尼多 (5~ 160 μM)和水杨苷(0. 001~ 100 μM)对心肌细胞收缩的抑制作用;此外,基于 3D 呼吸道平滑肌细胞 (ASMCs) 阵列,结合凝 胶成像系统,探究了 TAS2Rs 激动剂桔皮素(20 μM)对呼吸道平滑肌细胞的舒张作用。     

TAS焊接技术在传感器等器件制造中的应用

本文介绍了采用Ar H_2混合气体保护自动点焊(TAS焊)新工艺,实现了压力传感器、电感传感器等器件的封装,文中对传感器结构及焊接特点,TAS焊接设备及工艺作了阐述。     

工程陶瓷镜面加工工艺

用工程陶瓷材料制造机器结构零件已经在越来越多的领域得到应用，其精密加工技术也随之迅速发展。在加工过程中，陶瓷已加工表面质量的提高，不仅可使零件的耐磨性得到改善，而且其使用的可靠性也显著提高，因此一些陶瓷零件如喷咀、针问、精密快规和密封件等已要求表面粗糙度值不应大于Rao．05μm。本文针对ZrO2、Si3N4扣Sialon陶瓷进行了摩削、研磨和抛光等工序的实验研究，探索了陶瓷外圆表面和平面的精加工工艺，并成功地实现了表面粗糙度Ra0．011～0．016μm的镜面加工。一、外圆表面的研磨抛光1．实验装置图1所示为陶瓷件外圆研磨…     

从2001年PITTCON看微型全分析系统的发展

2001 PITTCON仍在美国新奥尔良召开.会议交流论文1900多篇,参展厂家一千多家,参会人数24970人,都比上一年有所减少,但它仍不失为全世界有关分析化学和分析仪器最大的国际会议和展览会,充分体现了分析化学和分析仪器的一些最新发展.其中特别值得注意的是微型全分析系统(μ-TAS),整个会议有4个分会和近百篇论文是专门关于这一主题的.这在PITTCON的历史上是破天荒的.下面就会上所见所闻,结合本人在会后学习研究中所了解到有关情况,对μ-TAS的发展谈一些个人看法.     

μＸＬ系统在200MW火电机组中的应用

本文对μＸＬ系统的特点进行了剖析，并结合具体工程，阐述了μＸＬ系统在火电厂中的应用方式，并提出一些应用设计中应注意的问题及解决方法。     

隧道式纳米级轮廓仪的研究

介绍两种结构形式的基于电子隧道效应的纳米级三维轮廓仪。其纵向分辨率可达０．０２ｎｍ，横向分辨率可达０．２ｎｍ，扫描范围分别为４０μｍ×４０μｍ和１４μｍ×１４０μｍ。可直接对φ５０ｍｍ和φ１３０ｍｍ的大尺寸样品表面进行纳米级的超微观形貌检测与分析。文中给出了一些超精表面的超微观形貌测量的结果。     

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.     

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。     

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....     

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.