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基于电阻测量原理的新型棉花水分在线自动测量仪 总被引:14,自引:0,他引:14
根据电阻式棉花水争测试原理,利用Phillp380C552单片机设计了一种新型棉花水分在线自动测量仪。棉花压紧机的运动位置由霍尔器件自动判断;测量结果的温度补偿由单片机的计算功能实现。通过与主控系统的串行通信,实现了对测试仪的自动控制。实测结果表明,仪器含水率测量误差小于0.6%,低于国内现有同类仪器的测量误差(1%)。 相似文献
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分析了CIE1931XYZ色度系数光谱三刺激值与棉花色泽参数之间的关系,取得棉花体表的颜色参数,实现对棉花色泽的客观分级处理。为保证分级的正确性,还讨论了准确模拟人眼视觉色觉功能的y^-(λ),z^-(λ)光电探测器的研制方法,并介绍了系统的工作原理和测量系统的设计。 相似文献
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光电积分式色度仪器的定标研究 总被引:3,自引:0,他引:3
目前,新颖的光电积分式色度仪器的光电探测器具有若干种不同的光谱匹配方式,而且仪器都应用了电流电抵变换器电路及数字显示技术,并结合有软件功能。校正这种仪器可运用色度学知识,通过仪器硬件和软件的结合,能快速、精确地对任何色源进行一次性可靠定标。实际应用证明本方法是方便而有效的。本文拟介绍这种定标原理及其实施方法,并针对由浙江大学光仪系研制成功的CL-Ⅱ型彩色亮度计和WB-1型彩色电视白平衡自动调试仪的定标实例加以粗浅的探讨。 相似文献
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一种新型便携式甲霜灵胶体金试纸条显色分析仪的研制 总被引:3,自引:0,他引:3
甲霜灵胶体金试纸条用于现场快速检测进出口蔬菜甲霜灵农药残留量.在对试纸条光谱测量分析的基础上,研制出一种基于图像测量的便携式甲霜灵试纸条显色分析仪器,该仪器集成了样品滴定、定时检测、显色度分析、身份认证等多种功能,实现了试纸条的自动检测、显色度数值分析和数据存储.实验测定了浓度为2~50 ng/mL的标准浓度甲霜灵农药滴定的试纸条,结果表明,浓度<40 ng/mL时,显色度与浓度线性相关,而浓度>40 ng/mL时,显色度差异不明显. 相似文献
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本文开发了一种用于颜色产品微面积精细颜色测量、采用脉冲氙灯光源、光纤环形照明、全息平场凹面光栅型脉冲多通道快速分光显微色度仪。该仪器结构简单、色分辩率高、色品坐标精度为0.002、最小分辨线视场为0.01mm,测量光谱范围为可见区、光谱分辨率为10nm、测量时间间隔短、能进行较暗物体和荧光物体的微面积精细颜色测量,并能给出各种标准照明体和各种色度系统下的色度参数 相似文献
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介绍了一种自动测试汽车车灯色度仪器的设计原理、结构框图和精度分析。仪器采用微机控制、数据采集、标准判别和表格打印, 是车灯行业理想的测试仪器。 相似文献
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Clarence W.DE SILVA 《Instrumentation》2019,(4):72-84
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... 相似文献
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INTEGRAL EQUATION METHOD'S APPLICATION IN HOLE-EDGE STRESS OF COMPOSITE MATERIAL PLATE WITH DIFFERENT SHAPED HOLES 总被引:1,自引:0,他引:1
LI Cheng ZHENG Yanping 《机械工程学报(英文版)》2008,21(6):115-118
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. 相似文献
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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. 相似文献
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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... 相似文献
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分布动态载荷识别的抗噪处理 总被引:2,自引:2,他引:0
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. 相似文献
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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。 相似文献
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The fraction defective of semi-finished products is predicted to optimize the process of relay production lines, by which production quality and productivity ar... 相似文献
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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.... 相似文献
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J. A. Williams 《Lubrication Science》1997,3(3):267-306
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. 相似文献
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CHEN Sunyi 《机械工程学报(英文版)》2007,20(6):13-17
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. 相似文献