双CCD视觉传感器的建模及优化设计

依据几何成象原理建立起双ＣＣＤ视觉传感器坐标的数字模型,导出其有效视场的计算公式,并分析了有效视场、坐标测量精度和传感器结构参数之间的关系。综合导出的公式及的判据,编制出相应的优化设计软件,由计算结果发现,当给定有效视场及各结构参数的测量误差值时,可寻求该传感器的最优结构布局,使坐标测量精度最佳。     

视觉测量传感器系统结构参数设计分析

依据三角法建立了基于线结构光和对称式双目立体视觉的两种典型视觉传感器坐标测量系统数学模型.通过对坐标测量模型及传感器各结构参数之间的相互关系分析,研究了线结构光视觉传感器和双目立体视觉传感器坐标测量系统结构参数及其误差对系统综合测量精度的影响关系特性.在对各结构设计参数综合分析的基础上,提出了视觉传感器坐标测量系统结构参数优化准则,并给出了线结构光视觉传感器及双目立体视觉传感器坐标测量系统结构参数的一般性设计原则与方法.     

基于多极板电容传感器测量原油含水率的研究

设计了测量原油含水率的多极板式电容传感器及测量电路;建立了多极板式电容传感器测量原油含水率的数学模型,得到了原油含水率变化量与多极板式电容传感器等效电容变化量之间的函数关系.进行了五极板式电容传感器和单极板式电容传感器测量油水混合物含水率的对比实验.实验结果表明采用五极板式电容传感器测量油水混合物的含水率,相对于采用单极板式电容传感器测量油水混合物的含水率的测量精度有大幅度的提高;而且采用五极板式电容传感器测量油水混合物的含水率,无论是在低含水率端还是在高含水率端其测量结果都比较稳定.     

双目传感器结构优化设计

综合分析了摄象机摆放姿态与双目传器有效视场的关系，同以往简单分析方法不同，文中全面分析了各种情况不同结构参数对传感器精度的影响，介绍了摄象机标定及传感器结构参数获取的方法，实验数据表明，上述分析正确，测量结果令人满意。     

多视觉传感器CAN总线检测系统的设计

研究了多传感器CAN总线视觉检测系统的架构方式与设计方法,给出了视觉传感器的控制电路单元CAN总线控制方法,多路视频信号切换开关单元的信号切换方法,CAN总线控制网络通讯的软件设计.文章介绍的CAN总线控制系统实现了多视觉传感器的分布式网络化控制,尤其适合对实时性、可靠性和精度等要求较高的大型多传感器视觉测量系统的实时控制.     

一种提高双目视觉测量精度的逐步逼近方法

针对空间坐标对图象平面坐标的非线性光学映射关系,本文提出了逐步逼近实现３－Ｄ空间坐标计算的测量方法。该方法对摄象机的摆放姿态与双目传感器的装配精度要求较低,可去除介质折射产生的坐标计算误差。结合局部标定法,对摄象机光学系统的畸变误差进行校正。实验数据表明,在对双目传感器不提出较高要求的测量条件下,测量结果令人满意。     

基于长冲程振动台导轨弯曲校正的低频振动传感器校准方法

针对长冲程振动台的导轨弯曲对于基于振动台的低频振动传感器灵敏度幅值校准的影响,采用机器视觉方法测量导轨弯曲。通过建立校正模型消除导轨弯曲的影响,以提高灵敏度幅值的校准精度。导轨弯曲测量结果表明,被校振动传感器的负载越大,导轨弯曲越大,对灵敏度幅值校准的影响越大。与地球重力法的对比试验表明,在0.04～2 Hz范围内弯曲校正后的灵敏度幅值校准精度提升了一个数量级。     

低精度液位测量电路设计

针对低精度的液位测量,利用开关霍尔元件并结合单片机技术设计了一种低精度的液位测量传感器,对传感器的测量原理、测量电路、信号处理电路进行了介绍。     

基于高精度匹配点的对极几何估计

提出了一种以Harris算子和空间位置约束条件自动提取的初始特征点为引导,利用小面元模型进行灰度分布的拟合曲面求极值点的超精度特征点定位方法。并利用超精度的特征点估计立体图像对的对极几何约束关系。通过对真实图像的对比实验证明该方法能有效的提高基本矩阵估计精度,与传统的基于像素级特征点的估计算法相比,平均余差值降低了3.4%~21.4%,算法运行速度快,能在视觉测量中有效地提高测量精度。     

基于差商法的嵌入式角位移传感器自标定

为了摆脱对高精度基准器具的依赖实现对嵌入式角位移传感器的现场标定,结合传感器的结构特点提出了一种利用单个读数头测量值差商的方法实现自我标定。该方法利用傅里叶逼近模型将读数头的误差分离为多次谐波的叠加,采用测量值向前差商的方法获取标定模型的中间变量,运用泰勒展开对差商方法进行了误差估计,并通过提高差商阶数降低模型误差,为了保证标定精度,结合最小二乘算法对标定参数进行了寻优。运用自标定方法对两台不同对极数的嵌入式角位移传感器进行了标定实验,并与传感器常用的比较标定方法进行了对比实验。实验结果表明,两台传感器的误差分别从标定前的±30″和±25″,降低至±2.6″和±2.2″,精度得到了大幅度提高,最终的标定参数与传感器实际的误差成分相吻合,标定精度与比较标定的精度基本相同,能够满足嵌入式角位移传感器的高精度、高效率标定要求。     

The Research of Anti-Wear Properties of Organomolybdenum Compounds in the Engine Oils

A four-ball tester was used to evaluate the anti-wear performance of three kinds of organomolybdemun compounds in the engine oils, i. e., molybdenum dialkyldithiophosphate (MoDDP), molybdenum dialkyldithiocarbamate ( MoDTC), and sulphur and phosphorus freeorganomolybdeum (Molybdate). The results indicate that a low concentration of MoDDP doesn' t improve the anti-wear properties of the commercial engine oils, but a high concentration of MoDDP can obviously improve the anti-wear properties and the load-carrying capacity of the engine oils. MoDTC doesn' t improve the antiwear properties of the engine oils, but worsens the anti-wear properties of the oils. Signifi can timprove ment of frictional and wear characteristics is obtained with Molybdate added in the commercial engine oils and the formulated oils.     

Certification Becomes Important for the I Quality; and Safety Supervision of the Chinese Liquor Sector

The end of 2007, over 200 unit products of more than 80 Chinese firms have passed the quality grade certification for liquor products. These products involve distilled spirits, beer, wine, yellow wine, fruit syrup wine and others, and cover over 80% of the national top-branded liquor products.……     

Deposition and Coating Properties on CVD Tungsten

Surface characterization and microstructure studies are performed on chemical vapor deposited (CVD) tungsten coating. There is about 2 μm thickness diffusion layer of tungsten in the molybdenum substrate. The thermal shock test shows tungsten coating has good adhesion with molybdenum substrate, but the elements of oxygen and carbon in the tungsten coating have the bad affection to the adhesion. The result of high-temperature diffusion experiment is the diffusion rate from molybdenum substrate to tungsten coating is faster.     

Analysis of marine hydrobiont lipid extracts as possible cryoprotective agents

We studied a combined effect of the cryoprotectants both of lipid and carbohydrate origin at the presence of DMSO or without it on cell viability and the RNA synthesis in the embryonic mollusc and echinoderm cell cultures obtained at different developmental stages. Cryoprotective properties of exogenous lipids correlated with their thermotropic behavior. Lipid extracts from marine hydrobiontes, which thermal transitions are characterized by relatively small part of calorimetric thermogram area lying at temperatures above 0 °C (6–18%), were found to possess a considerable cryoprotective activity. The results are discussed in relation to the prediction of the cryoprotective activity of lipid extracts for marine animal cells. In addition, it was found that marine invertebrate cells can be cryopreserved without DMSO at the presence of trehalose and lipid extracts of some marine hydrobiontes.     

Low-Temperature Properties of Silver

Pure silver is used extensively in the preparation of high-temperature superconductor wires, tapes, films, and other configurations in which the silver not only shields the superconducting material from the surrounding materials, but also provides a degree of flexibility and strain relief, as well as stabilization and low-resistance electrical contact. Silver is relatively expensive, but at this stage of superconductor development, its unique combination of properties seems to offer the only reasonable means of achieving usable lengths of conductor. In this role, the low-temperature physical (electrical, thermal, magnetic, optical) and mechanical properties of the silver all become important. Here we present a collection of properties data extracted from the cryogenic literature and, to the extent possible, selected for reliability.     

Early ironwork in Biscay: Survey,excavation, experimentation and materials characterization. An integral study of the mountainside ironworks (ferrerías de monte or “haizeolak”)

ABSTRACT

The production of iron in Biscay (Basque Country, Spain) has been a hallmark of this territory of the North of the Iberian Peninsula throughout its history. The Archaeology team of the Basque Country Mining Museum has spent 13 years, so far, studying the origins of this activity through the evidences left at the old pre-hydraulic iron production workshops known as mountainside ironworks (ferrerías de monte) or haizeolak. It has catalogued 170 archaeometallurgical sites of this type in Biscay, and the archeological excavation of some of them has led to the knowledge of the different stages of the production process that took place in these workshops. The team has also experimentally reproduced the work carried out in a mountainside ironworks from the High Middle Ages, and it has currently started the characterization process of this type of activity through the study of the collected materials.     

Mechanism Study on the Wear of CrAlTiN Coated High-Speed Steel Twist Drills Under Dry Cutting Conditions

As demands about environment protection are growing up, dry cutting technology is getting more and more concerns from all over the world. Main works performed here are study on dry cutting performances and wear mechanisms of M2high-speed steel (HSS) twist drills with CrAlTiN multicomponent coatings, which was deposited using magnetron sputter ion plating system, in drilling 45 and 30CrMnSiA steel, and their comparisons to those in drilling the same steel but using monolayer CrN and commercial TiN coated drills. Drilling performances of drills are evaluated mainly through the measurements of width on outer corner flank land and the cutting forces. Results show that performances of CrAlTiN coated drills are better than those of monolayer CrN and TiN coated drills. In drilling 45 and 30CrMnSiA steel, the average tool life of the CrAlTiN coated drills are 17.2 and 11.8 times higher than those of the uncoated drills. Observing wear of the drill with scanning electronic microscope, results show that there is no crack or spallation of the CrAlTiN coatings in wear zones. Main mechanism of the wear here is adhesion.     

Study on Bond Ability of Arc-Spraying Coatings with Different Surface Pretreatment on Cast-Iron

Arc spraying coatings are widely used in various applications, but uncommon in cast iron substrate. Different surface pretreatment technology is tested on substrates of gray cast iron. Surface roughness and residual stress were measured by TR200 and X-ray diffraction analyzer. Influence of different surface pretreatment methods ( dry blasting and fusebond) on roughness and residual stress was analyzed. The arc-sprayed coatings of wire 3Cr13 (φ2mm) on gray cast iron substrate is studied. The microstructure and interface of bonding layer were observed by SEM. The bond strength was taken by tensile test. Results show that bond strength with grit blasting is higher than fuse-bond; it is feasible to make wire 3Cr13 coating with arc spraying on cast iron substrate roughened by grit blasting.     

Structural Characteristics of TiO2 Ceramic Coating by Micro-Plasma Oxidation

TiO2 ceramic coatings with thickness of 20 μm were formed on the surface of pure titanium by micro-plasma oxidation. Their micro-structures were investigated by by using X-ray diffraction and their surface images were detected by using scan electronic microscope. There were three kinds of TiO2 coatings, pure anatase type TiO2 phase, mixed phases consisted of rutile type TiO2 phase and anatase type TiO2 phase, pure rutile type TiO2 phase. The coating surface with the pure anatase type TiO2 phase is rough, while the coating surface with the pure rutile type TiO2phase is smooth. The upper coating surface with the mixed type TiO2 phases is anatase type TiO2 structure and the subsurface of the TiO2 coating is rutile type TiO2structure.     

Evaluation of fatigue life of steel using steel grain size

The insightful discussion of the relationship between the construction of metallographic and fatigue life and proposition of mathematical relationships describing this relationship was conducted in the paper. This paper presents a method for estimating the fatigue life, based on the construction of the microstructural material taking into account the grain size and the participation of ferrite and pearlite phase.