一种改进的Canny边缘检测方法

传统Canny边缘算子通过像素点的梯度幅值是否大于梯度方向两侧的像素的梯度幅度值来判定边缘.针对传统Canny边缘算子的判断边缘的方法,分析Canny边缘算子在边缘检测时容易出现边缘点的漏检而造成边缘不连接现象,结合Harris检测算法改进Canny边缘算子来连接断开的边缘并提高检测准确率.实验结果表明,改进的算法检测边缘连接性好并具有更好的检测准确度.     

基于数学形态学改进Canny算法的红外图像边缘检测

在应急搜救中,红外图像边缘检测起到至关重要的作用,众多学者都致力于研究如何能够进一步提高红外图像边缘检测的性能,本研究提出一种将数学形态学与Canny算子进行融合的算法,称为应用于红外图像边缘检测的改进Canny算法。算法研究完成后,将通过Matlab仿真软件进行仿真,将改进后的Canny算法与传统Canny算法的仿真结果进行比较,可以发现该算法在边缘检测和细节处理方面的性能更为优良。     

一种改进的植物叶片病斑区域边缘提取技术

针对传统Canny算子边缘检测时容易丢失边缘细节的缺陷,提出了一种改进的植物叶片病斑区域边缘提取技术。运用最大类间方差法对病害图像进行二值化,添加对两个斜方向上梯度信息的提取,更加完整地保存了梯度信息,从而得到更完整的边缘图像。实验结果表明,本文方法能够有效地滤除图像中的噪声,检测到细节梯度,去除伪边缘和噪声边缘,得到更加精确的病斑区域边缘。     

应用Canny算子的织物疵点检测改进算法

为克服当前Canny算子在织物疵点边缘检测中存在的阈值设定、滤波参数选择等自适应问题,提出一种基于Canny算子的改进算法。通过分析不同种类的织物疵点特征,选择不同参数的高斯滤波器,对织物疵点图像进行滤波处理;采用自适应形式获取图像边缘信息的阈值,避免了因阈值取值过高或过低而无法获得较好织物疵点的边缘信息的问题,同时还可根据不同织物疵点类型选择不同的滤波参数。结果表明,改进后的Canny算法可有效地检测到织物疵点的边缘细节,具有较好的自适应能力,并且提高了算法的有效性。同时对典型的织物疵点进行检测并与传统算法比较,其检测效果更优。     

混合蛙跳优化算法的裱糊线机器人边缘提取

为了提高裱糊线机器人视觉系统定位精度,降低图像边缘冗余信息与噪声影响,提出将基于混合蛙跳优化算法的Canny算子应用于裱糊线机器人裱纸的边缘检测中。通过采用最大类间方差作为混合蛙跳算法的目标函数,自适应迭代优化Canny算子双阈值,实现裱糊线有效提取。仿真试验结果表明,该算法优化Canny算子可较好检测裱纸图像的边界轮廓,自适应获取最优阈值,弥补传统Canny算子需要人为设定的缺点,提高了检测精准性,同时具备一定降噪效果。该算法较粒子群优化算法、传统Canny算法C/A分别降低3.33%、33.39%,C/B分别降低了14.94%、54.55%。     

一种分块自适应文字图像边缘检测新方法

传统catmy算法通过比较图像梯度值与人为给定阁值,进行图像边缘提取,无法自适应确定阀值、一些基于改进的最大类间差算法（Otsu算法）,通过计算梯度直方图和类间方差极大值的,自动寻找出Canny算法需要的分割闽值实现对传统Canny算法的改进,对于文字图像边缘提取效果并不好。本文利用梯度直方图峰值搜索的方法设定Canny算法的上闽值,通过对图像分块计算,自适应处理亮度不均的文字图像。关键词：边缘提取;自适应闽值分割;Cmmy算子;峰值搜索     

基于OpenCV的机器人目标检测候选区域生成算法

针对当前目标检测算法主要集中在GPU上运行且对家庭机器人任务针对性不强的问题,提出了一种基于OpenCV的RMFC算法。该算法首先对输入图像进行裁剪、腐蚀、Canny边缘检测操作;其次使用二维顺序查找的方法过滤地面边缘以外的区域;随后使用卷积判断模块抽取物体的位置,最后在视频测试集上测试,结果表明该方法在快速提高检测速度的同时兼顾了准确性及针对性,并得到每幅图像少于10个的候选区域。     

融合边缘检测的四帧差分运动目标检测

传统的三帧差分运动目标检测算法易出现空洞及虚假边缘等现象,为了对其进行改进,本文提出了一种融合边缘检测的四帧差分运动目标检测算法。首先对四帧连续图像采用Canny边缘检测算子快速提取边缘图像,然后对四帧连续的边缘图像进行四帧差分运算,最后通过阈值分割和形态学处理完成对运动目标的提取。实验结果表明,该算法计算简单,连通性好且准确率高,可满足实时检测的要求。     

基于最大熵快速迭代算法和边缘算子的织物疵点分割

将信息熵引入图像处理中,把疵点图像分为背景和目标两部分,分别对两个区域进行处理;通过求最大熵值的快速迭代算法,在满足信息熵最大要求的前提下对织物疵点区域进行分割,然后利用Canny边缘检测算子对分割后的疵点图像进行边缘检测,从而达到识别织物疵点的目的。仿真实验结果表明,将最大熵快速迭代算法与边缘算子结合进行疵点分割识别的方法是有效的。     

人体轮廓机器视觉检测算法的研究进展

为了更好地将轮廓视觉检测方法应用于非接触式二维人体围度测量,总结了近年来轮廓视觉检测的方法,包括基于边缘算子的检测、基于数学形态学的检测、基于水平集的主动轮廓模型的检测算法。通过实验效果图对比,重点评述了轮廓视觉检测方法的边缘清晰度、抗噪能力以及目标边缘定位能力,其中特别探讨了Canny边缘算子在优化与改进方面的研究进展。相关研究为实现背景和穿着复杂情况下的人体轮廓视觉检测提供了理论参考。最后阐述了人体轮廓视觉检测存在的挑战及机遇,指出人体轮廓视觉检测在非接触式二维人体围度尺寸测量方面具有很好的发展前景。     

Reliable identification of grapevine rootstock varieties using RAPD PCR on woody samples

Since grapevine ( Vitis spp .) rootstock material is being traded increasingly as disbudded woody material a lack of distinctive morphological features on such material necessitates an alternative and reliable means of identification. Methods described here were developed for rapid and efficient extraction of DNA from woody samples rich in phenolic compounds and polysaccharides, and for subsequent identification of varieties by RAPD PCR. Using these methods, and with the application of only one selected RAPD primer, we were able to differentiate sixteen rootstock varieties, including the seven varieties most commonly used in Germany. Problems commonly encountered with reproducibility of RAPD patterns were avoided by choosing primers with a dinucleotide sequence and a high G/C content that allowed a rather high annealing temperature of 45°C. Methods described here should also be useful for other horticultural crops, especially those with woody tissues rich in phenolic compounds and polysaccharides.     

An internet compendium of analytical methods and spectroscopic information for monomers and additives used in food packaging plastics

An internet website (http://cpf.jrc.it/smt/) has been produced as a means of dissemination of methods of analysis and supporting spectroscopic information on monomers and additives used for food contact materials (principally packaging). The site which is aimed primarily at assisting food control laboratories in the European Union contains analytical information on monomers, starting substances and additives used in the manufacture of plastics materials. A searchable index is provided giving PM and CAS numbers for each of 255 substances. For each substance a data sheet gives regulatory information, chemical structures, physico-chemical information and background information on the use of the substance in particular plastics, and the food packaging applications. For monomers and starting substances (155 compounds) the infra-red and mass spectra are provided, and for additives (100 compounds); additionally proton NMR are available for about 50% of the entries. Where analytical methods have been developed for determining these substances as residual amounts in plastics or as trace amounts in food simulants these methods are also on the website. All information is provided in portable document file (PDF) format which means that high quality copies can be readily printed, using freely available Adobe Acrobat Reader software. The website will in future be maintained and up-dated by the European Commission's Joint Research Centre (JRC) as new substances are authorized for use by the European Commission (DG-ENTR formerly DGIII). Where analytical laboratories (food control or other) require reference substances these can be obtained free-ofcharge from a reference collection housed at the JRC and maintained in conjunction with this website compendium.     

Aroma characterization of various apricot varieties using headspace–solid phase microextraction combined with gas chromatography–mass spectrometry and gas chromatography–olfactometry

The characterization of the aromatic profile of several apricot cultivars with molecular tracers in order to obtain objective data concerning the aromatic quality of this fruit was undertaken using headspace–solid phase microextraction (HS–SPME). Six apricot cultivars were selected according to their organoleptic characteristics: Iranien, Orangered, Goldrich, Hargrand, Rouge du Roussillon and A4025. The aromatic intensity of these varieties measured by HS–SPME–Olfactometry were defined and classified according to the presence and the intensity of grassy, fruity and apricot like notes. In the six varieties, 23 common volatile compounds were identified by HS–SPME–GC–MS. Finally, 10 compounds, ethyl acetate, hexyl acetate, limonene, β-cyclocitral, γ-decalactone, 6-methyl-5-hepten-2-one, linalool, β-ionone, menthone and (E)-hexen-2-al were recognized by HS–SPME–GC–O as responsible of the aromatic notes involved in apricot aroma and considered as molecular tracers of apricot aromatic quality which could be utilized to discriminate apricot varieties.     

Tests of potential functional barriers for laminated multilayer food packages. Part I: Low molecular weight permeants

The advent of the functional barrier concept in food packaging has brought with it a requirement for fast tests of permeation through potential barrier materials. In such tests it would be convenient for both foodstuffs and materials below the functional barrier (sub-barrier materials) to be represented by standard simulants. By means of inverse gas chromatography, liquid paraffin spiked with appropriate permeants was considered as a potential simulant of sub-barrier materials based on polypropylene (PP) or similar polyolefins. Experiments were performed to characterize the kinetics of the permeation of low molecular weight model permeants (octene, toluene and isopropanol) from liquid paraffin, through a surrogate potential functional barrier (25 μm-thick oriented PP) into the food simulants olive oil and 3% (w/v) acetic acid. These permeation results were interpreted in terms of three permeation kinetic models regarding the solubility of a particular model permeant in the post-barrier medium (i.e. the food simulant). The results obtained justify the development and evaluation of liquid sub-barrier simulants that would allow flexible yet rigorous testing of new laminated multilayer packaging materials.     

Analysis of benzo[a]pyrene in spiked fatty foods by second derivative synchronous spectrofluorimetry after microwave-assisted treatment of samples

A simple, rapid and inexpensive method has been developed for the determination of benzo[a     

The development of reference materials for paralytic shellfish poisoning toxins in lyophilized mussel. II: Certification study

This paper describes the second part of a project undertaken to develop certified mussel reference materials for paralytic shellfish poisoning toxins. In the first part two interlaboratory studies were undertaken to investigate the performance of the analytical methodology for several PSP toxins, in particular saxitoxin and decarbamoyl-saxitoxin in lyophilized mussels, and to set criteria for the acceptance of results to be applied during the certification exercise. Fifteen laboratories participated in this certification study and were asked to measure saxitoxin and decarbamoyl-saxitoxin in rehydrated lyophilized mussel material and in a saxitoxin-enriched mussel material. The participants were allowed to use a method of their choice but with an extraction procedure to be strictly followed. The study included extra experiments to verify the detection limits for both saxitoxin and decarbamoyl-saxitoxin. Most participants (13 of 15) were able to meet all the criteria set for the certification study. Results for saxitoxin.2HCl yielded a certified mass fraction of <0.07 mg/kg in the rehydrated lyophilized mussels. Results obtained for decarbamoyl-saxitoxin.2HCl yielded a certified mass fraction of 1.59+/-0.20 mg/kg. The results for saxitoxin.2HCl in enriched blank mussel yielded a certified mass fraction of 0.48 +/- 0.06 mg/kg. These certified reference materials for paralytic shellfish poisoning toxins in lyophilized mussel material are the first available for laboratories to test their method for accuracy and performance.     

Announcing a new international peer-reviewed journal:Food Science and Human Wellness now accepting manuscript submission in English

<正>We are pleased to announce the launch of a new international peer-reviewed journal-Food Science and Human Wellness,ISSN 2213-4530,which is an open access journal,produced and hosted by Elsevier B.V.on behalf of Beijing Academy of Food Sciences.Food Science and Human Wellness is an international peer-reviewed English journal that provides a forum for the dissemination of the     

Chinese CTP Market

According to Printing and Printing Equipment Industries Association of China（PEIAC）＇s statistics to the plate manufucturer in China, in 2013, the actual offset plate production has reached 346 million square meters in China. Among them, the CTP production volume was 245 million square meters, up by 11% than that of last year; the total sales of the CTP plate was 239 million square meters, up by 13%.     

Preparatory Work of Print China 2015 is Going Smoothly

正Held at Guangdong Modern International Exhibition Center,Print China 2015 will cover 7exhibition halls,besides the original Hall No.3,4,5,6,7,the newly built F zone of Hall 3 will be used too.The total area will be140,000 square meters.Hall 3:Offset and large printing equipment,package printing equipment,post press