基于机器视觉的低对比度纸病识别算法研究

利用机器视觉识别纸病时,若背景与目标纸病的对比度低,且采用单一的边缘检测算法,将会出现对目标纸病边缘定位不准确、抗噪性能不好等问题。对此,提出了一种解决方法,即首先分别用LOG算子和基于数学形态学的边缘检测方法对低对比度纸病图像进行边缘检测,然后对这两种边缘检测算法得到的图像进行小波融合,融合得到的图像中纸病边缘定位准确且具有一定的抗噪性,最后,对此进行了实验验证。研究结果表明,文中提出的解决方法可行,即可将该方法用于基于机器视觉的低对比度纸病识别。     

基于相位一致性的低对比度纸病识别算法研究

针对机器视觉检测低对比度纸病,存在常规的阈值分割会引起低对比度纸病信息丢失以及边缘检测存在鲁棒性差的问题,本课题提出了一种基于相位一致性算法识别低对比度纸病的方法,并与常规的阈值分割以及边缘检测中具有代表性的canny算子进行了对比分析。结果表明,当识别低对比度纸病时,本课题提出的方法不仅保留的有用信息较常规阈值分割的多,而且鲁棒性较canny算子的边缘检测好。     

基于位平面的纸病检测算法研究

针对当前纸病检测算法存在抗干扰能力差、定位不准确和运算复杂等问题,提出一种基于位平面的纸病检测算法。首先,采用自适应中值滤波算法对纸病图像进行滤波,然后,对滤波后的图像进行位平面分解,并运用格雷码对位平面加以增强,最后,使用数学形态学对其进行边缘检测,得到最终的纸病检测结果。仿真结果表明：该方法运算简单,能够较好地检测出纸病缺陷,并具有较好的抗干扰性和定位准确性。     

基于Gabor滤波器的织物疵点检测

从疵布结构纹理模型出发阐述Gabor滤波器疵点边缘增强原理。根据织物特征设计织物自适应Gabor滤波器,确定Gabor滤波器的中心频率。再利用设计好的Gabor滤波器对方向性特征畸变织物疵点进行增强,并通过阈值处理完成疵点边缘检测。实验证明,织物自适应Gabor滤波器对方向性特征畸变疵点具有良好的边缘增强效果,可以突出织物纹理的能量,抑制疵点纹理的能量,同时该算法的最高检测速度可以达到7m/min。     

基于多尺度特征融合注意力机制的纸病分类方法研究

针对造纸工业中传统纸病分类算法准确率低的问题,本课题提出一种多尺度图像增强结合注意力机制的方法;采用锐化滤波器和对比度增强操作获得图像对直线信息的响应,同时利用Sobel边缘检测获取图像对边缘信息的响应,然后将这些响应分别放进卷积神经网络(CNN)中提取浅层局部信息后进行特征融合,得到全局信息,最后利用注意力机制,通过关注这些图像中最有特点的部分,进行纸病分类。实验表明,该方法优于HOG+SVM、LBP+SVM以及传统CNN等方法,在自建数据集上,分类准确率可达到96.63%;与现有基于CNN的纸病分类算法相比,所需的数据量更少,分类效果更好。     

边缘跟踪算法在多纸病图像分割中的应用

为了解决纸病检测中多纸病图像分割问题,提出了一种改进的边缘跟踪算法。该算法首先搜索得出纸病边缘的链码,并通过记录坐标取得图像的外接矩形,然后提取每个矩形中的纸病图像。结果表明,该算法能够有效提取纸病图像的边缘,并对多纸病图像能够完成精确的分割。     

基于快速傅里叶变换和改进分水岭算法的纸病实时检测复合算法

本课题提出了一种适合高速宽幅造纸机纸病在线实时检测的复合算法,该算法的基本思想是：首先通过快速傅里叶变换（fast Fourier transform,FFT）将时域图像转换到频域,以便使用频域图像与高斯（Gaussian）高通滤波器做乘积运算进行滤波;再通过快速傅里叶逆变换（inverse fast Fourier transform,IFFT）将频域中的图像转换到时域,以便下一步使用运算速度较快的分水岭算法对滤波后的图像进行快速缺陷分割,实现纸病在线实时检测。利用采集到的2000余张纸病图片进行纸病检测实验,结果表明,本课题提出的复合算法具有快速、高效、适用性强、分割效果好等优点,可满足纸病在线检测对图像处理算法实时性和准确性两方面的要求。     

基于粒子群优化算法与形态学的纸病图像检测方法

针对传统边缘检测算子对纸病图像检测的不足,提出了一种基于粒子群优化算法和数学形态学的边缘检测方法。首先通过粒子群优化算法得到图像最优分割阈值,将图像二值化,然后利用数学形态学中的腐蚀运算对纸病图像进行边缘检测。仿真结果表明,相比传统算法,该方法的检测结果更真实地反映了纸病图像的形态特征,且边缘定位准确,取得了较为理想的检测效果。     

基于FPGA的纸病检测预处理算法的实现

利用DSP Builder工具在MTALAB/Simulink中设计纸病图像预处理算法,然后将算法的Simulink模型转换为FPGA的硬件代码。硬件在环测试验证了算法可以对纸病图像进行滤波、检测边缘和定位处理。利用FPGA对纸病图像进行预处理,可以满足纸病检测系统需实时处理大量数据的要求。     

基于Gabor优化选择的彩色图像边缘检测算法

针对图像边缘检测过程中易出现图像细节信息丢失以及边缘断裂等问题,提出一种基于Gabor优化选择的图像边缘检测算法。Gabor滤波器虚部可以较好地描述像素周围的方向变化信息以及伸缩、平移、旋转不变性。利用3个尺度8个方向的Gabor虚部滤波器组提取图像边缘特征;分别计算滤波后各图像的熵值,对于同一方向、不同尺度下的滤波图像,选择熵值最大的滤波通道作为最优;根据二范数进行边缘特征融合,通过迭代式阈值分割方法获得边缘检测结果。实验结果表明,所提算法边缘定位准确且边缘细节信息丰富,边缘连续度较高。     

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