可见光热反射成像测温中图像配准技术研究

为了消除被测件与测温仪器相对位移对光热反射成像测温结果的影响,研究了亚像素量级的图像配准算法,配合以基于压电陶瓷的三轴纳米位移台,实现了对位移的实时修正.采用傅里叶变换、频域卷积及sine函数近似等方法完成了能够实现亚像素级图像配准的算法,实时计算被测件与测温仪器的相对位移;搭建了一套光热反射成像测温实验装置,采用了三...     

亚像素数字散斑相关测量中计算窗口的选择

提出了一种亚像素数字散斑相关测量计算窗口的选择方法.采用模拟散斑图像,利用亚像素数字散斑相关测量中的相关系数插值法、拟合法及梯度算法原理,研究了计算窗口大小对这三种计算方法的测量精度和计算效率的影响,得出了不同亚像素精度要求下,可选择的计算方法及其最佳计算窗口.研究结果表明,测量精度越高,所需的计算窗口越大,选择合适的计算窗口可以提高测量精度和效率.     

基于路径匹配技术的高精度微位移检测系统

文中研究了用图像技术来检测微位移的问题 ,提出一种路径匹配微位移检测算法。该算法能自动搜索移动前后图像中匹配边缘 ,并避免了常用图像匹配算法复杂度太大的问题。文中还对算法进行了可信性分析并给出了实验结果。理论分析和实验结果表明 ,路径相关微位移检测算法运算量小且获得了亚像素的准确度     

基于信号采样的相位相关法亚像素级配准方法研究

为解决小模数齿轮视觉测量中凸显的工业相机高空间分辨率与大视场相互制约的矛盾,对基于相位相关原理的亚像素级配准方法进行了研究。分析相位相关法在应用于具有亚像素位移量的图像时,互功率谱傅里叶逆变换后产生主峰副峰的原因及两者幅值与亚像素位移量的对应关系,将该方法用于小模数齿轮图像配准,实验结果表明:该方法的配准误差小于0.002 pixel;在忽略非相关区域影响的情况下,通过误差分析得出该方法存在的周期为1 pixel的非累积性误差,其中由函数近似引入的误差小于5×10^-8pixel。     

应用光栅刻线与CCD测量运动位移的研究

将计量光栅作为标准刻线,应用到对微细物体高精度定位的工作台上,并提出了一种新的直接获取运动位移的方法.调整光路使CCD获取清晰的光栅图像;对图像进行分析处理,计算出栅距与像素之间的映射关系:再对工作台移动前后的光栅图像进行对比,采用基于X-Y图的相位差比率算法获取像素位置差;从而计算出工作台的实际运行位移.实验结果表明,该方法能简单快速地实现微电子加工领域亚像素级的测量.     

3种亚像素位移测量算法的比较研究

梯度法、曲面拟合法和N-R法是数字散斑相关方法中提高位移测量精度的3种主要亚像素位移算法。研究了3种算法的原理并进行了数值模拟仿真。首先使用计算机模拟生成一系列位移为0.01 pixel的散斑图,并在生成的图像中添加方差不同的高斯噪声,对3种算法在噪声条件下的精度进行比较,结果显示在精度要求为0.01 pixel时,梯度法的噪声方差上限为0.006,N-R法的噪声方差上限为0.000 5,而曲面拟合法的计算精度具有较大不确定性,无法保证精度,梯度法更适用于工程应用。     

几何重心法亚像素提取算法研究

研究了一种基于显微图像的几何重心法亚像素提取算法,用于实现超低转速的在线测量。首先根据显微图像法将超低转速的转动测量转换为平动测量; 然后利用提出的几何重心法的亚像素提取算法,解决了目前常用的曲线拟合法和梯度法的亚像素提取时间长、抗图像干扰能力弱的问题。几何重心法的核心是在整像素提取的基础上,在3×3的像素范围内,分别计算参考像素灰度值与提取的整像素灰度之差的指数值,在获取的3点指数值上,利用几何重心法提取出亚像素值。通过光栅基准平台微位移抓拍图像的验证,提出的几何重心法比曲面拟合法、梯度法用时短,平均用时<0.2s,提取的亚像素值的标准差<1/1000像素,满足了超低转速在线测量的基本要求。     

基于Halcon的弹芯尺寸精密检测算法研究

针对弹芯尺寸传统人工方式检测难、精度低等问题,提出了一种基于机器视觉的亚像素级尺寸检测算法.该算法以性能优越的机器视觉软件Halcon为开发平台,利用亚像素级阈值分割提取出边缘轮廓,然后选定各检测参数的感兴趣区域(Region of Interest,ROI)并进行特征提取,最后利用最小二乘法及Tukey权重函数对轮廓进行亚像素边缘拟合,根据返回的拟合轮廓的相关参数即可计算出弹芯尺寸.实验结果表明:该算法将尺寸误差控制在0.01mm以内,能够达到亚像素级的检测精度,并实现在线检测.     

基于高亚像素精度的图像处理测量坦克炮炮口振动位移

本文介绍了某次炮口振动测试与验证,在测试中以某坦克炮为测试对象,利用高速摄像对零度角射击姿态下的坦克炮炮口进行拍摄,对所拍摄图像进行了亚像素级别的图像处理,最终给出弹丸出炮口时的振动位移.该测试在靶场射击条件下,将炮口振动位移的测试精度提高到0.1mm量级.为了验证高速摄像的亚像素分辨精度,搭建了一套测试验证系统,该系统利用微型振动台产生微小振动位移,由固定在振动台台面上的一只加速度计通过数据积分得到相应的振幅,以此来实测亚像素分辨精度.本文在业内首次验证了高量级亚像素分辨率的图像分析在大口径火炮测试中的可行性,显示出其在大口径火炮炮口振动测试中的优势与潜力.     

基于亚像素综合定位匹配算法的MEMS平面运动测量

动态测试对MEMS的设计、制造和可靠性具有非常重要的意义．提出了快速高精度的综合亚像素定位匹配算法，应用于MEMS平面运动测量．该综合算法把标准化协方差相关法、亚像素步长相关法、曲面拟合法、序惯相似性检测算法和单纯形法有机结合，综合运用各算法的优点，达到了提高亚像素定位速度和精度的目的．通过位移测量实验和对硅微陀螺仪质量块面内振动及谐振频率的测量，验证了该综合算法的可行性和有效性．     

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.     

Effect of Permeable Crystalline Material on Steel Reinforcement Corrosion of Concrete

Permeable crystalline materialcan permeate into pores and cracks of concrete and catalyze the reaction between Ca(OH) 2and unhydrated cement to generate a great quantity needle non-soluble crystals, which can stop up the pores and cracks of concrete, and increase the impermeability of concrete. This paper reported the results of a study conducted to evaluate steel reinforcement corrosion of concrete specimens uncoated and coated with permeable crystalline material as well as mixed with the permeable crystalline material. The properties evaluated for corrosion test were water impermeability, water absorption, compressive strength and potential. The results of water impermeability, water absorption, compressive strength clearly showed that the permeable crystalline material could prohibit water, any soluble salts and moisture from penetrating the concrete to cause corrosion, leaking, and other problems, and it did increase the compressive strength, which was favorable for protection of corrosion of reinforcing steel. Moreover, it was concluded from the potential-time curve that the steel reinforcement of uncoated specimen was in the state of activation whereas that of other specimens coated and mixed with the permeable crystalline material was in the state of inactivation. Above all, it was indicated that the permeable crystalline materialis very effective to protect the steel reinforcement of concrete from corrosion.     

The Research and Application About "Dry Peeling Off" Technology for Airplane Surface Paint Layer

In this paper, the principle of spurting take off lacquer were introduced; and with orthogonal method the unsaturate polyester was prepared ;it was easy to peel airplane paint layer off with this material and equipment.     

Quality Study of Honeycomb Core Shaping Without Wax Stabilization

Sandwich panels utilizing honeycomb cores result in lightweight, high-strength units that are very rigid. Indeed, they give honeycomb panels the best strength-to-weight ratio of any construction type available. Conventionally, the wax is poured into the cell of the core to strengthen the structure and prevent the core from being crushed during milling. Much time and labor is required to wax, mill, and clean the cores. In this study, the process of pouring wax into the core was skipped. In other words, the cutter directly milled the core. Experiments showed that the compressive strength of the core produced without wax stabilization was only 3% lower than that of cores produced using the traditional method. In addition, the drum peel strengths of cores produced without wax stabilization were 38.4% higher than cores produced using the traditional method, in which residual wax seriously polluted the adhesive. It was also found that eliminating the wax process can reduce costs.     

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.     

In-process thermal treatment of polylactic acid in fused deposition modelling

Polylactic acid (PLA) is one of the most widely used open source fused filament fabrication materials due to its ease of extrusion, biodegradability, and mechanical strength. The mechanical strength of PLA largely depends on the proper growth of its semi-crystalline structure, which can be severely impaired by a low rate of crystallization, particularly in open source printers. This can be further aggravated by the non-uniform thermal distribution of heat that causes improper curing among the extruded beads of the printing material. As a result, PLA printed on open source printers does not achieve the best mechanical properties. This research, for the first time, proposes an additive-free solution implemented through a detailed set of experimentation to improve the curing rate through in-process temperature variations to cure the joints among the beads. Scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and Fourier transform infrared (FTIR) spectroscopy is used to confirm the improvements in the bead joints. This work is conducted in two phases of experiments. In the first phase, a full factorial ANOVA is used to investigate various process parameters and the important variables are used in the second phase to print test specimens in four different sets.     

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.