基于机器视觉的番茄颜色分级检测研究

利用机器视觉技术对水果进行分级具有对水果无损害、分级精度高、速度快等优点,但现有的番茄颜色分级方法有其局限性。文章提出了一种对番茄图像高光消除后,在HSV颜色模型下用主色共生矩阵提取番茄表面颜色纹理特征进行分级的方法。实验表明该方法比利用颜色直方图进行分级的方法具有更高的分级精度。     

基于机器视觉的番茄颜色分级方法的研究

为提高番茄品质检测效率及分级精度,建立基于机器视觉理论的番茄视频在线检测理论模型,即将番茄图像采集、增强、滤波平滑去噪、分割后转换为HIS颜色模型.以国家标准(GB8852-88)定义番茄成熟度与色调(Hue)颜色特征的关系判定其成熟度等级,定义H分量等于零为红色.在此基础上开发视频检测系统,有效提取番茄表面颜色特征参量,实现高效、准确番茄品质线性分级.     

一种FFT的Hu矩的番茄形状特征提取

目前基于机器视觉的番茄形状检测算子检测到的形状特征单一,相关的深入研究较少,为进一步探索合适的形状特征参数及检测算子,将Hu矩作为特征参数并利用支持向量机实现了番茄的形状检测分类,准确度较高。首先设计采用Laplacian算子与Sobel算子进行算法融合对采集到的番茄图像进行自适应增强处理;然后采用最小错误率贝叶斯决策算子对平番茄图像进行图像分割得到番茄目标二值化图像。然后对得到二值化后的番茄图像进行归一化处理,使得归一化后的图像具有平移、旋转、尺度缩放不变性的Hu参数,通过提取目标番茄的7个Hu矩特征值参数,最后将这些特征值输入支持向量机中,完成番茄无损分级检测。试验采用VS2010验证算法,对正常果形、轻度畸变果形、重度畸变果形共计1000个样本进行了训练测试,结果表明经过改进增强图像以及改进Hu矩算子对番茄正常果形的分级精度达到93.3%,符合实际番茄检测精度的要求。     

自然彩色化双通道实时图像融合系统

考虑硬件资源与运算速度的需求,设计了一种基于数字信号处理(DSP)的具有自然彩色效果的红外与可见光图像融合系统.该系统采用软硬件结合的方法进行双通道图像配准,基于YCbCr空间实现伪彩色融合,然后利用自然真彩色参考图像对融合结果进行颜色传递.系统采用基于统计特性的颜色查找表技术,利用参考图像与伪彩色融合图像的统计特性修正颜色查找表,提高了计算效率.在系统的硬件平台上进行了实验,结果表明,系统融合图像接近自然色彩,在保留可见光图像细节的前提下,有效地突出了红外图像中的热目标.该系统融合速率达到25 frame/s,能够实现红外与可见光图像的实时融合与自然彩色化,有助于观察人员快速地发现目标,弥补了单一图像传感器的不足.     

基于彩色CCD的摩擦焊接温度场测量系统

根据彩色CCD三基色测温原理,设计了摩擦焊接的温度场测量系统.采用CCD摄像头对焊接界面进行高速、连续拍摄,得到温度场图像,DSP对图像进行预处理后,对温度进行计算,然后使用伪彩色增强方法,通过不同颜色来反映焊接界面各部分的动态温度分布状况.为提高测量的精度,通过黑体炉实验对计算公式中的参数进行标定,并根据实验数据进行了插值修正.TMS320DM647的高速运算能力和丰富的片上资源保证了测量的实时性,伪彩色处理后的温度场图像可以方便、直观地反映出温度场的分布.     

基于计算机视觉的番茄颜色检测研究

以提高番茄人工分拣效率为目的,利用计算机视觉技术,建立番茄检测试验平台,将采集的番茄图像转化为HIS颜色模型,进行二值化,研究番茄成熟度。文章对番茄规定的四个等级进行分级,其分级的结果为:超优、优、良和未成熟的判断正确率分别为80%、60%、40%和80%,总的判断正确率为65%。     

在均匀颜色空间中实现彩色图像的颜色量化

颜色量化是将原有图像中的多种颜色根据人的视觉效果归类为较少的颜色,从而用这些较少种类的颜色重新生成一幅新的图像,使量化后的图像与原图像的差别即量化误差最小.采用了将RGB非均匀颜色空间变换到L^*a^*b^*为基准的均匀颜色空间的方法,在L^*a^*b^*均匀颜色空间中对彩色图像进行颜色量化,从而解决了量化误差相对人眼不均匀的问题.首先将彩色图像的像素数据保存在单链表中,然后对链表进行扫描,并把本次扫描得到的色差最小的两个节点合并成一个新的节点.经过足够的动态运算后可得到量化处理后的图像调色板.实验结果表明,本方法具有普遍性、唯一性,可以减小量化误差,提高颜色量化的准确性.     

基于图像处理技术的番茄成熟度检测研究

提出了一种利用图像处理技术判别番茄成熟度的方法。将实验温室大棚采集的番茄果实图像转化为RGB颜色模型,人工划分阈值并提取果实坐标,以原图像素与人工分量阈值的方差为依据,判别番茄成熟过程的4个时期,为研制番茄成熟度判别设备提供了参考。     

机械产品设计的色彩参数优化选取研究

为提高机械产品色彩设计的智能化水平,提出了机械产品设计的色彩参数优化选取方法。构建机械产品色彩设计中的图像网格空间分布结构模型,对其进行特征参量寻优模板匹配。依据其特征参量,得到机械色彩人性化设计的颜色特征RGB的量化值,对机械色彩进行颜色空间划分,在三维颜色空间范围内采用最短距离误差修正算法(MSD算法)进行色彩搭配和颜色的融合性设计,确定机械产品设计的色彩参数,实现优化选取。仿真实验表明,该方法提高了色彩搭配的融合能力,输出机械色彩设计图案的峰值信噪比较好,说明色彩参数的选取效果较好。     

图像可视在线铁谱传感器的图像数字化处理技术

为实现图像可视在线铁谱传感器的磨粒图像自动辨识,建立数字图像获取系统,探讨铁谱图像数字化处理方法。研究了铁谱图像的预处理方法,对比在RGB和YUV颜色空间对铁谱图像的灰度化处理效果,采用不同的微分模板对平滑后图像进行锐化处理;探讨减背景法和自动阈值法在铁谱图像磨粒分割中的应用效果;给出适用于在线铁谱图像的定量描述方法。研究表明,采用YUV颜色空间的明视度分量可以得到平滑的灰度图像,合理的模板选择可以使微分法在锐化磨粒边缘的同时保持整体图像的平滑;铁谱图像的磨粒分割结果表明,减背景法由于采用人工选取门限值而难以适用于在线铁谱图像的处理,而自动阈值法可以根据铁谱图像自动选取合适的阈值以达到良好的分割效果;采用磨粒百分覆盖面积作为定量指标可反应良好分割的铁谱图像中的磨粒统计质量分数。     

Minimal Realization of Linear Graph Models for Multi-physics Systems

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...     

INTEGRAL EQUATION METHOD＇S APPLICATION IN HOLE-EDGE STRESS OF COMPOSITE MATERIAL PLATE WITH DIFFERENT SHAPED HOLES

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.     

Non-monotonic material contrast in scanning ion and scanning electron images

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.     

Application of Feature Extraction through Convolution Neural Networks and SVM Classifier for Robust Grading of Apples

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...     

分布动态载荷识别的抗噪处理

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.     

基于MELTAC-N平台的核电厂安全级DCS环网研究与测试

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。     

Short-Term Relay Quality Prediction Algorithm Based on Long and Short-Term Memory

The fraction defective of semi-finished products is predicted to optimize the process of relay production lines, by which production quality and productivity ar...     

End-to-End Multiview Gesture Recognition for Autonomous Car Parking System

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....     

The laboratory simulation of abrasive wear

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.     

ANGULAR DISTORTION ALLOWABLE VALUE AND ASSESS METHOD OF WELD ON COKE TOWER

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.