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为降低线阵CCD拼接测量难度,提出改进的多光学系统线阵CCD拼接测量法。根据检测幅宽和精度要求,将较宽的被测幅面分成若干区域。各区域放置独立可调的光学成像系统及线阵CCD。调整各光学系统,使总成像范围覆盖整个被测幅面。几个线阵CCD同步驱动并行采集。图像信号通过PCI高速数据采集系统送入计算机。为提高判别速度,采用多尺度灰度形态学方法实现快速图像增强和缺陷判别,每秒钟可处理20幅2048像素200像素的8bit灰度图像。实验表明,可实现8个线阵CCD拼接检测幅面宽1.2m彩色感光胶片的表面质量,检测速度最高可达90m/min,可识别直径在0.1mm以上的缺陷,准确率在96%以上。 相似文献
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设计了一套用于刀具几何参数精密测量的光学检测系统.该系统利用物方远心光路、柯勒照明等手段对刀具检测仪器中的传统光学成像方式进行了改进,保证了被测刀具成像精度.通过光学计算和误差分析,系统测量误差小于±1.4 μm.将该套装置应用到刀具几何参数的测量仪器中,实验测试数据表明仪器的测量精度达到±2μm. 相似文献
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基准尺作为摄影测量长度基准,其精度直接影响测量结果的准确性,为了保证基准尺长度的测量精度,设计了由气体静压导轨、激光干涉仪、CCD成像系统组成的测量系统。分析了影响测量精度的因素,并对组成基准尺的标志圆成像位置、CCD相机光轴、激光干涉仪、基准尺和CCD成像系统绕自身光轴旋转的调节误差进行了计算分析,用于指导CCD成像系统、激光干涉仪和基准尺的调节。最后应用该系统对基准尺进行多次测量,结果表明基准尺长度测量的标准差可达到1 μm,满足工业摄影测量的要求。 相似文献
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变焦距光学系统降低公差灵敏度的方法 总被引:1,自引:0,他引:1
针对高分辨力CCD探测器(1 k×1 k,6.3 μm×6.3 μm),确定了一个可见光波段连续变焦光学系统,传递函数(MTF).接近衍射极限.本文通过公差分析可知前固定组和变倍组的公差灵敏度非常高,对加工和装调提出了苛刻的要求.该方法根据设置前固定组轴向移动补偿和焦面轴向补偿来降低前固定组的公差灵敏度和提高系统成像质量,并分析了前固定组轴向补偿机械结构的可行性.通过分析公差灵敏度产生的原因,提出对敏感表面上的入射角进行合理优化设计以有效降低公差灵敏度.实验结果表明,在不增加成本的前提下降低加工和装调难度,提高系统整体性能. 相似文献
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为了准确测量远距离炸点平均高度,采用了双线扫描 CCD 成像的方法并建立了测量系统理论模型。首先采用了望远式成像光学系统对远距离炸点进行成像,采用柱面镜进行成像变换;采用Zemax软件对成像光路进行了模拟,模拟点列图结果表明了系统在物距为20 m时,能够在5 m范围内有效测量炸点光的平均高度。最后,采用曲线拟合的方法求出光斑中心位置并对测量系统进行了线性标定。经实验验证本测量系统可以在物距为20 m处测量炸点的平均高度最高约为3 m,测量精度可以达到1.95%。所设计的炸点平均高度测量系统满足了远距离、大范围的测量要求,系统运行稳定、可靠,采用双线阵CCD的测量方法有效的消除了物距不能确定的影响。 相似文献
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基于三次拟合方程畸变校正的光电测量系统 总被引:6,自引:2,他引:4
在大视场光电测量系统中,光学系统产生的畸变使目标在线阵CCD上的成像偏离了理论成像点,导致系统产生测量误差.为了减小该误差,提高系统的测量精度,根据畸变产生机理,设计了由11个等距目标点组成的畸变检测装置.根据检测得到的系统实际畸变变化情况,需要拟合出系统测量时目标点在线阵CCD上成像位置的补偿方程.以检测装置测量拟合得到的三次补偿方程作为畸变校正的数学模型编写了测量校正程序,对光电测量系统进行了实验检测.测量结果表明,当目标物物高为200.115mm时,按照拟合的补偿方程进行计算补偿,可将畸变误差从校正前的-2.08mm提高到校正后的0.05mm,并使系统整体检测精度从1.039%提高到0.025%. 相似文献
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《International journal for numerical methods in engineering》2018,113(9):1488-1506
In this paper, we present a new method for inserting several triangulated surfaces into an existing tetrahedral mesh generated by the meccano method. The result is a conformal mesh where each inserted surface is approximated by a set of faces of the final tetrahedral mesh. First, the tetrahedral mesh is refined around the inserted surfaces to capture their geometric features. Second, each immersed surface is approximated by a set of faces from the tetrahedral mesh. Third, following a novel approach, the nodes of the approximated surfaces are mapped to the corresponding immersed surface. Fourth, we untangle and smooth the mesh by optimizing a regularized shape distortion measure for tetrahedral elements in which we move all the nodes of the mesh, restricting the movement of the edge and surface nodes along the corresponding entity they belong to. The refining process allows approximating the immersed surface for any initial meccano tetrahedral mesh. Moreover, the proposed projection method avoids computational expensive geometric projections. Finally, the applied simultaneous untangling and smoothing process delivers a high‐quality mesh and ensures that the immersed surfaces are interpolated. Several examples are presented to assess the properties of the proposed method. 相似文献
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Steffen Müller-Probandt 《材料科学与工程:中英文B版...》2018,(4):161-177
We associate a variety of innovations with the term "Industry 4.0". The pioneer of many 4.0 modifications forms the basisfor the trend towards the integrated di... 相似文献
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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. 相似文献
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Janet Lang 《Materials and Manufacturing Processes》2017,32(7-8):857-866
ABSTRACTThe production of ferrous metal increased during the Roman Late Republican period, Principate and Empire. The direct bloomery process was used to extract the metal from its ores using slag-tapping and slag-pit furnaces. The fuel was charcoal and an air blast was introduced by bellows-operated tuyères. Iron formed as a bloom, often as a spongy mass of metal, which contained impurities from the smelting process, including unreacted ore, fuel, slag and fragments from the furnace walls, while the metal was often inhomogeneous with varied carbon contents. Blooms were either smithed directly into bars or ingots or they were broken up, which also allowed the removal of gross impurities and a selection of pieces with similar properties to be made. These could then be forge-welded together and formed into characteristically shaped ingots. Making steel in the furnace seems to have been achieved: it depended on the ore and the furnace and conditions within it. Surface carburization was also carried out. Iron and steel were used extensively in construction and for tools and weapons. Fire welding was often used to add pieces of steel to make the edges of tools and weapons, which could be heat-treated by quenching to harden them. 相似文献
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Standards are the basis for production enterprises to organize production ex-factory inspection trade 《中国标准化(英文版)》2008,25(1):24-25
Standards are the basis for production enterprises to organize production, ex-factory inspection, trade (delivery) and technical exchanges, product certification, quality arbitration and supervision.…… 相似文献
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A flow calorimeter for enthalpy increment measurements on condensed gases is presented. A better knowledge of the properties of the liquefied natural gas is needed, and therefore a liquid loop has been designed for our flow calorimeter. The fluid loop in the calorimeter is designed in order to avoid the two-phase region, since two phases would give compositional disturbances in the measurements. The avoidance of the two-phase region is made possible by increasing the pressure of the test fluid after the measurement section, then heating the fluid at super-critical pressure past the critical point. Finally, the fluid is throttled to the low-pressure gas state at the inlet condition of the compressor that circulates the fluid. To perform the pressure increase, a new cryogenic pump has been designed. To evaluate the new equipment, measurements were taken on liquid ethane over the temperature range 146–256 K at pressure between 0.9 and 5.1 MPa. 相似文献
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The end of over unit products of more than Chinese firms have passed the quality grade certification for liquor products. These products involve distilled spirits beer wine yellow wine fruit syrup wine others cover over % of the national top-branded liquor products.…… 《中国标准化(英文版)》2008,25(1):30
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.…… 相似文献
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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. 相似文献
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S. K. Malhotra Paramanand Singh A. Thirunavukkarasu 《Materials and Manufacturing Processes》2006,21(7):652-657
Al2O3-ZrO2 nanocomposites were developed starting with the solgel process. Composite alumina-zirconia nanopowders were synthesized from metallorganic precursors (Aluminium secondary butoxide and zirconium Iso propoxide) using the solgel process. The parameters affecting the synthesis—solvent, concentration of precursor, R/H ratio (i.e., dilution of water in solvent)—were varied as also the temperature and pH. BET and TEM were used to measure nanosize. Diffuse reflectance spectroscopy and also qualitative optical absorption led to identical particle size estimate. The variation of process parameters was used to study the effect and interdependence of process parameters. Artificial Neural Networks was used to rigorously analyze the process. Although this led to confirmation of interdependence of parameters, the presence of a single overwhelming solvent variable was also established. Then the optimal process was used to synthesize more nanopowder. To produce bulk nanocomposite the nanopowders were sintered by varying the temperature and time period. The sintered lithoids were probed with a vickers hardness tester to measure elastic modulus, hardness, and fracture toughness. The results showed high elastic modulus, modest hardness, and very high fracture toughness. 相似文献