计算机视觉方法视域下的纸张填料颗粒粒径计算分析方法研究

基于扫描电子显微镜拍摄纸张填料,以获取放大后填料图像,加以预处理,获得清晰的颗粒图像,并利用图像特征提取的连通域标记法与欧拉数算法识别统计填料颗粒,最终获得颗粒粒径分布数据。对计算机视觉方法计算分析所得数据与激光衍射法测量所得数据进行对比分析,结果表明,其测量样本粒径结果与激光衍射法测量结果相统一,可重复性良好,经济性、有效性突出,可在既定范围内利用此方法直接替代激光衍射法。     

苯乙烯-丙烯酸酯表面施胶剂的制备及应用

采用苯乙烯和丙烯酸酯合成了一种新型的表面施胶剂。分别利用红外光谱、激光衍射粒度分析仪和颗粒电荷测定仪对其结构性能、粒径分布及表观电荷密度进行表征测定,并对其应用性能进行研究。结果表明,合成的表面施胶剂粒径细小、粒度分布均匀,体积平均粒径为107 nm,均一性为0.250 2,带正电荷,电荷密度为747μeq/g。采用此施胶剂对纸张进行表面施胶后,纸张施胶度提高,白度和裂断长亦有所提高;将其与氧化淀粉复配,可以改善氧化淀粉的表面施胶性能。     

计算机图像处理技术在纸页Z向结构分析中的应用研究

采用扫描电子显微镜（SEM）对纸张的Z向结构进行了观测,进一步对所得的观测图片应用Image-Proplus5.0图像分析软件进行了计算机量化分析。以上计算机图像分析技术利用纤维、孔隙以及纸张所含的填料在扫描图片中的颜色深度差异,通过彩色分割和填充原理对纤维、孔隙和填料的分布特性分别进行分析检测。通过该图像分析技术,可以准确测量出分布在纸张Z向不同深度上纤维以及细小纤维的长度、宽度和面积,可以准确检测出在纸张Z向各层的孔隙尺寸、孔隙分布规律、孔隙数量和所占面积比率。     

淀粉包覆型硅灰石填料的制备及其在造纸中的应用

在纸张中添加矿物填料是节省植物纤维原料、提高纸张性能的重要手段,但同时也会造成纸张强度性能的下降。为了提高填料与植物纤维之间的结合强度,本文利用淀粉对硅灰石填料进行包覆改性,制备淀粉包覆型硅灰石造纸填料,分析淀粉包覆改性对硅灰石填料颗粒粒度、留着性能、抗剪切性能和纸张强度性能的影响。研究结果表明,硅灰石填料经淀粉包覆改性后,其颗粒粒径增大,粒径分布均一性得到较大改善,留着率显著提高,并具有较强的抗剪切性能;相比于添加未经淀粉包覆改性硅灰石填料的纸页,添加淀粉包覆改性硅灰石填料的纸页强度性能较高,且强度性能下降的趋势明显减缓。     

羧甲基壳聚糖/硫酸铝改性滑石粉在高加填纸中的应用

采用羧甲基壳聚糖和硫酸铝对造纸填料滑石粉进行表面包覆改性,对改性填料的应用进行了研究。结果表明,在羧甲基壳聚糖用量一定时,沉淀剂硫酸铝的用量对填料的改性过程和改性填料的应用性能有较大影响。当硫酸铝用量为6%时,与未改性加填相比,在灰分提高27.2%的前提下,加填纸张抗张指数仍可提高22.5%,同时加填纸张的白度和不透明度均较好。SEM观察表明,填料形态发生变化,颗粒粒径变大,形成了填料粒子的聚集体;加填纸张的SEM观察表明,滑石粉经改性后,能和纸张纤维形成更有效的吸附,提高填料和纤维之间的结合力,进而改善纸张的强度和纸料留着性能。     

淀粉颗粒粒径不同测定方法的比较

利用显微镜法、激光粒度法和聚焦光束反射仪法(FBRM)等3种不同方法分析分别测定了玉米淀粉、马铃薯淀粉和木薯淀粉颗粒粒径分布,并对这3种方法进行了分析比较。结果表明:显微镜法在测定淀粉颗粒粒径时非常直观,但是重复性较差,特别是粒度范围宽的样品,在测量时就会产生较大的误差,测出颗粒粒径大小为玉米淀粉(11.2μm)木薯淀粉(12.6μm)马铃薯淀粉(25.7μm);激光粒度法在测定淀粉颗粒粒径时,近球形颗粒重复性好,但是对于形状不规则的样品会产生较大误差,测出颗粒粒径大小为木薯淀粉(12.0μm)玉米淀粉(15.2μm)马铃薯淀粉(39.3μm);聚焦光束反射仪法(FBRM)分析测定淀粉颗粒粒径时,重复性好,能较好地测量颗粒粒径分布,测出颗粒粒径大小为玉米淀粉(24.0μm)木薯淀粉(27.3μm)马铃薯淀粉(31.3μm),可实现对淀粉在物理或化学处理过程中粒径和数量粒径变化的在线监测。     

新填料对纸张性能的影响

用相同分子结构和形态,不同目数的非金属矿体材作为新填料,逐步替换滑石粉抄纸成纸,通过测定纸张性能,考察新填料对纸张性能的影响,同时探索填料粒径对纸张性能的影响。实验发现,新填料替换部分滑石粉后,纸张物理强度有不同程度的下降,但是粒径较小的新填料,在完全替代的情况下,纸张物理强度与滑石粉加填的相当;同时,粒径越小的新填料替换滑石粉后,有助于提高纸张紧度、灰分、平滑度等指标;纸张油墨吸收性能与填料粒径大小关系较大,大粒径的新填料不利于油墨吸收。     

溶胶-凝胶法制备二氧化硅改性碳酸钙填料的研究

利用原位溶胶-凝胶法制备二氧化硅,对沉淀碳酸钙（PCC）进行表面改性,并采用光谱和显微镜分析技术对这种新型改性材料进行表征。结果表明,在偏三角形PCC晶体表面会覆盖一层紧密的二氧化硅层;通过热重分析发现,在适宜的实验条件下,二氧化硅在PCC表面的沉积量能够达到25%。虽然改性后PCC的平均粒径有所变化,但是用激光粒度仪测定的改性前后PCC的粒径分布相近。这一特性对改性PCC的应用至关重要,如将其用作造纸填料能够增加纤维与纤维之间的结合,提高纸张强度。     

视觉系统开发模块在芒果果面缺陷检测中的应用

探讨应用视觉系统开发模块进行芒果果面缺陷检测的方法。通过CCD采集芒果白光图像,分析确定所需图像区域的算法,采用面积标定法获得芒果缺陷图像,利用线性回归分析确定测量值和真实值之间的相关性。通过试验证明,该方法对检测芒果果面缺陷分级的相关检验性结果r为0．999,计算机视觉的检测结果与人工检测结果的误差小于0．3％,且具有较好的稳定性。     

机械活化木薯淀粉的光谱分析

采用机械活化的方法对木薯淀粉进行处理,利用X射线衍射、红外光谱及激光光谱等方法对处理后木薯淀粉的结晶结构、分子基团和粒径分布进行分析。研究结果表明,机械活化可以有效降低木薯淀粉颗粒的粒径,且粒径线性回归的趋势分布随活化时间不同而迁移,机械活化能破坏木薯淀粉的结晶结构,在X射线衍射图上表现为结晶衍射峰消失,机械活化可以增加木薯淀粉中反应基团游离羟基的数量,尤其使伯羟基的数量增加。     

淀粉-脂肪酸改性高岭土的制备及其在包装纸上的应用

To improve the bondability between clay filler and lignocellulosic fiber,Kaolin clay particles were modified using a starch-fatty acid complex method.The coating efficiency of starch on clay particle surfaces was investigated by measuring the dissolved starch in the supernatant.The experimental results indicated that more than 98%of the applied starch was precipitated onto the surface of the filler,and the resulting starch-fatty acid-clay composites had relatively good resistance against moderate shear force.The morphology,particle size,andζpotential of the starch modified filler were also determined with scanning electron microscopy,Malvern particle size analyzer,and Malvern Zetasizer,respectively.An aqueous slurry of linerboard pulp containing 5～15wt%modified fillers was used for handsheet preparation,and the effects of the addition of modified filler on the paper properties were studied.At a dosage of 10%of the modified filler(based on filler), the retention of the filler was higher than 75%.The strength properties of paper with starch modified fillers were improved by approximately 15%when compared against those of paper with unmodified fillers.     

Quality grading of Atlantic salmon (Salmo salar) by computer vision

ABSTRACT:  In this study, we present a promising method of computer vision-based quality grading of whole Atlantic salmon ( Salmo salar ). Using computer vision, it was possible to differentiate among different quality grades of Atlantic salmon based on the external geometrical information contained in the fish images. Initially, before the image acquisition, the fish were subjectively graded and labeled into grading classes by a qualified human inspector in the processing plant. Prior to classification, the salmon images were segmented into binary images, and then feature extraction was performed on the geometrical parameters of the fish from the grading classes. The classification algorithm was a threshold-based classifier, which was designed using linear discriminant analysis. The performance of the classifier was tested by using the leave-one-out cross-validation method, and the classification results showed a good agreement between the classification done by human inspectors and by the computer vision. The computer vision-based method classified correctly 90% of the salmon from the data set as compared with the classification by human inspector. Overall, it was shown that computer vision can be used as a powerful tool to grade Atlantic salmon into quality grades in a fast and nondestructive manner by a relatively simple classifier algorithm. The low cost of implementation of today's advanced computer vision solutions makes this method feasible for industrial purposes in fish plants as it can replace manual labor, on which grading tasks still rely.     

基于数字图像及随机最小二乘的红提串果粒尺寸检测分级方法

红提尺寸是衡量其品质的重要指标,为了实现整串红提的尺寸分级,本研究提出了一种基于机器视觉的尺 寸分级方法。通过双通道相机同时采集红提的红-绿-蓝（Red-Green-Blue,RGB）图像和近红外（near infrared,NIR） 图像,利用归一化超绿法去除RGB图像中干扰的绿色果梗信息,同时利用形态学重构的亮度局部极大值的方法对 NIR图像中的红提果粒进行识别和定位。采用梯度分割法有效地截取果粒轮廓并去除边缘轮廓中的干扰弧段,再利 用随机最小二乘椭圆检测的方法提取果粒尺寸,并对整串红提分级。采用该方法对42 串红提进行尺寸检测分级, 正确分级38 串,分级正确率为90.48%。实验结果表明：该方法分级正确率高,能够为葡萄市场分级提供技术支持。     

基于机器视觉的织物洗涤后尺寸稳定性评价

针对现有手工测量织物洗涤后尺寸变化方法存在误差大和精度低的问题,尤其是在洗涤后织物试样形状不规则情况下,手工测量结果难以全面准确反映织物整体尺寸变化,本文提出了基于机器视觉方法实现织物洗涤前后面积变化的精确检测,以面积变化率为指标来评价织物洗涤后尺寸稳定性。选择了6种不同规格的纯毛织物为试验材料,设置不同的洗涤、漂洗和脱水程序对试样进行洗涤,待干燥后采用机器视觉系统获取试样图像。对试样图像进行处理得出试样洗涤前后经、纬向平均长度和面积的变化率,以这些指标对试样尺寸稳定性进行评价。与人工测量方法相比,机器视觉方法可以实现对织物洗涤后尺寸变化的完全表征和准确评价,并可为织物设计和洗涤程序优化提供参考。     

Particle Size Distribution in Tomato Concentrate and Effects on Rheological Properties

The particle size distribution of a tomato concentrate was determined by wet sieving. Wet sieve fractions were then investigated by microscopy and a method based on laser diffraction. Both methods showed that the size of many particles was considerably larger (up to two to three times) than the diameter of the pores through which they have passed during wet sieving. This was explained by the deformability of the tomato cell wall. Effects of particle size distribution on rheological properties were studied by standardizing wet sieve fractions (dry matter, pH). Highest values for yield stress and apparent viscosity were found for the 90–125 and 125–180 μm wet sieve fractions.     

数字图像处理技术结合偏最小二乘法定量分析柑橘质量

目的：构建柑橘质量模型,实现其计算机视觉法质量检测与在线分级。方法：以湖南湘中成熟中期涟红温州蜜柑为研究对象,对计算机视觉系统采集的各柑橘的4 幅图像进行图像裁切、图像去背景、图像二值化与取反操作后,提取柑橘区域像素,以柑橘区域像素与图像像素比为自变量,建立柑橘质量偏最小二乘回归(PLS)预测模型。结果：柑橘质量预测绝对误差为－ 14.9092～4.9981g,平均误差为－ 3.9278g,误差标准差4.5210g,± 10g 质量内的正确识别率为93.3333%,± 8g 质量内正确识别率76.6667%。结论：通过计算机视觉技术进行柑橘质量在线分级和生长期中挂果质量的监测是可行的。     

Laser diffraction particle sizing by wet dispersion method for spray-dried infant formula

A laser diffraction particle sizing method involving wet analysis could be adapted effectively to measure the accurate particle size distribution of a spray-dried infant formula. Polar, polar aprotic and non-polar solvents, such as ethanol, methanol, acetone, pentane, heptane and hexane, were tested as dispersants for wet analysis. Non-polar solvents such as pentane, heptane and hexane found to be suitable dispersant because the shape of the infant formula particles in non-polar solvents was similar before and after the measurement while the particles had dissolved in the other solvents. The particle size distributions (PSD) of the infant formula determined by laser diffraction (Malvern Master Sizer, UK) using the dry analysis method with air was unsuitable because some parts of the primary and aggregated infant formula particles had been destroyed. The PSD graph of the air dispersion was shifted toward a smaller particle size from that of hexane dispersion. Overall, it is believed that laser diffraction particle sizing involving wet analysis with non-polar solvents may provide a suitable particle sizing method for infant formula products that is better than an air dispersion method.     

豆浆前处理工艺对其粒径分布及感官品质影响的研究

利用激光衍射粒度分析仪考察了离心、过滤、胶体磨处理、均质、热处理对豆浆稳定性及粒径分布的影响,并通过感官评价方法对豆浆品质进行了评定。结果表明,离心处理对粒径影响最明显,3000r/min,10min离心可使D[4,3]减小为0.487μm,沉淀率仅为0.44%;250目过滤则仅对粒径大于160μm的颗粒有效;均质作用比胶体磨处理效果更明显;豆浆经90℃,15～20min热处理最适;感官评价结果基本反映豆浆粒径分布状态的差异。     

基于光电技术的棉纤维杂质快速测定

针对棉纤维杂质人工检测耗时长、劳动强度大等问题,提出一种基于光电技术的棉纤维杂质机器视觉测定方法。首先通过改变平滑模板窗口尺寸对棉纤维图像自适应中值滤波优化,然后采用Otsu算法自适应选取分割阈值,并遍历整个图像,进行边缘断裂端点的连接、边缘生长与连接,搭建光电检测系统原型,实现了棉纤维杂质的快速测定。实验结果表明:该方法能够有效去除图像噪声,避免伪边缘的产生,检测到的杂质边缘清晰完整。光电检测耗时较GB/T 6499—2012《原棉含杂率试验方法》降低95.1%,结果间误差为2.35%,杂质粒数与杂质面积比参数结果误差均在2.1%以内,能够有效用于棉纤维杂质的快速准确测定。     

应用机器视觉的鞋面数量统计与尺寸测量

针对鞋面数量统计和尺寸测量过程中人工检测方法效率低、成本高的问题。提出利用机器视觉的鞋面数量统计与尺寸测量方法。采用基于边缘方向的模板匹配算法对鞋面进行数量统计。运用最小外接矩形（MER）算法对鞋面进行尺寸测量。为验证方法的可靠性,对3种鞋面分别在光照变化、混乱和遮挡条件下进行了检测实验,并与绝对误差和算法、归一化相关系数法和Hausdorff距离匹配算法的检测结果进行了对比。将MER测量结果和人工测量结果进行对比,结果表明：基于边缘方向的模板匹配算法在复杂环境下的鲁棒性更高,可以完成鞋面数量统计;MER方法和人工测量的相对误差在0.67%以内,满足工业生产中的实际需求。