DISPLACEMENT CONTROL AND KINETIC ANALYSIS OF A NOVEL VARIABLE DISPLACEMENT COMPRESSOR FOR AUTOMOTIVE AIR CONDITIONER

NOTAT1ONSR.--Mnged radius of cylinder bore center p.--Pressure in crankcase chamberR,--radius of piston m.--Mass of wObble plateRd--Arrnged radius of driving plate m, n--befficients of refrigerant's exPansion andro--AngUlar vdsitY compressiont--Time F.--Thrust fOrce on piston j from wobb1e platea--Nutating angle Fd.' Fd.' Fd.--Driving fOrce on wobble plate from drive6,--Angular opition of each cylinder bore center plateAb--Active area of pressure in crankcase chamber F.., F,., F..…     

水下位移检测的新方法

归纳了诸如液压油缸等水下移动部件行程位移的检测原理、优点及不足,并提出了新的检测装置原理。     

习家口油田中高粘度油藏盐水驱油提高采收率验证

高矿化度盐水比淡水驱油效率高,许多断块油田有高矿化度边底水存在,有条件利用天然水驱或边缘注水,充分发挥盐水驱油的优越性,提高油田水驱采收率。借鉴国内、外油田注高矿化度盐水提高采收率试验,根据油气田地质开发力学,分析习家口油田断块油藏地质基础和边水驱动开发特点,对比了五个中高粘度油藏盐水驱油采收率,表明已超过或将超过通用方法预测的最终采收率指标,作为盐水驱油提高采收率全过程的油田开发验证。结合一次采油和二次采油成果,建议开展习家口油田三次采油矿场试验,进一步提高最终采收率。     

A damage model for simulation of mixed-mode delamination growth

An interface element capable of modelling delamination progression under mixed-mode loading is presented. The kinematics of the element are based on the concept of regularised displacement discontinuity. This concept allows the interfacial constitutive equations to be formulated in terms of the traction vector of the interface and the corresponding displacement discontinuity. The decohesion within the interface, corresponding to delamination progression, is accomplished by assigning a non-associative perfectly plastic material model including isotropic damage to the interface element. All parameters of the model can be determined from experimental material data. Damage initiation is calibrated against the interlaminar fracture stresses whereas the evolution of damage is calibrated against the mixed-mode fracture toughness. The interface element has been implemented in a finite element code and results for simulations of standard fracture toughness tests are shown. The results display the applicability of the proposed model and the calibration procedure.     

获取动态图像位移矢量的灰度投影算法的应用

利用灰度投影算法获取图像运动信息,具有计算速度高、精度高等优点,但以往仅用来处理理想的动态图像即只有平移量的图像,限制了此方法的进一步的应用。本文通过分析几种较为复杂的动态图像获取图像运动特点,并采用相应的预处理方法使此算法能准确处理图像,拓宽了灰度投影算法的适用范围。     

Ф18′×28′球磨机主轴承瓦间隙的调校

文章介绍了 18′× 2 8′球磨机主轴承瓦的结构特点 ,分析了造成主轴承瓦移位的主要原因 ,提出了如何保证主轴承瓦与中空轴轴肩、下部球体与球座获得最佳间隙的调校方法。     

Application of 3D digital image correlation in maintenance and process control in industry

3D digital image correlation method is widely used for displacements measurements in laboratory conditions and for experimental applications in industries. In this paper we present enhancements of the standard method, which enable application of 3D DIC for in situ monitoring and process control in industries and out-door environment. Enhancements concern software modifications (new visualization methods and a method for automatic merging of data distributed in time) and hardware improvements (protecting equipment against hard environmental conditions).     

基于CPLD的光栅尺位移测量系统

介绍了光栅尺位移传感器的原理和利用CPLD设计该传感器的测量控制电路的方法,并且介绍了这种设计方法在三维光栅尺位移测量系统中的应用和相关VHDL程序。     

光纤位移传感器

一种用于状态监测和精密测量的新型位移传感器已经研制成功。它基于全光纤法布里－珀罗干涉仪原理。其分辨率高达１０－１０ｍ级。由于信号光束和参考光束在同一根光纤中通过，所以消除了温度变化、微弯效应以及电磁干扰等环境影响，并具有很高的测量稳定性。     

On a Neural Network that Performs an Enhanced Nearest-Neighbour Matching

We review some of the main methods of solving the image matching problem in Particle-Tracking Velocimetry (PTV). This is a technique of Experimental Fluid Dynamics for determining the velocity fields of moving fluids. This problem is a two-dimensional random-points matching problem that condtitutes a prototypal problem, analogous to the one-dimensional matching problem for Julesz [1] random-dot stereograms. Our study deals with a particular method of solution, namely the neural network algorithm proposed by Labonté [2,3]. Our interest in this neural network comes from the fact that it has been shown to outperform the best matching methods in PTV, and the belief that it is actually a method applicable to many other instances of the correspondence problem. We obtain many new results concerning the nature of this algorithm, the main one of which consists in showing how this neural network functions as an enhancer for nearest-neighbour particle image matching. We calculate its complexity, and produce two different types of learning curves for it. We exhibit the fact that the RMS error of the neural network decreases at least exponentially with the number of cycles of the neural network. The neural network constructs a Self-Organised Map (SOM), which corresponds to distorting back the two photos until they merge into a single photo. We explain how this distortion is driven, under the network dynamics, by the few good nearest-neighbours (sometimes as few as 20%) that exist initially. These are able to pull with them the neighboring images, toward their matching partners. We report the results of measuremnts that corroborate our analysis of this process. Received: 22 February 1999, Received in revised form: 22 September 1999, Accepted: 18 October 1999