基于改进Yolo v5的织物缺陷检测方法

针对纺织品表面缺陷检测算法速度低、泛化性能差及鲁棒性弱等问题,课题组提出了一种基于改进Yolo v5的织物表面缺陷检测方法。在Yolo v5骨干网络的基础上增加了卷积注意力模块,增强目标检测网络对特征图中重要信息提取并弱化无关特征;针对网络特征融合阶段特征尺度不一致造成的冲突问题,引入自适应空间特征融合的方法;在训练过程中使用迁移学习加快训练速度。实验结果表明：与未改进的Yolo v5算法相比,所提出的检测框架能够有效提高网络精度达98.8%,检测速度达83帧/s。该检测方法能满足实际工业要求。     

改进YOLOv7的纸张表面缺陷检测研究

提出一种改进YOLOv7的纸张表面缺陷一步式检测算法。首先将注意力机制模块CBAM融合到主干和特征提取网络结构,从空间和通道2个维度提取信息,提升小目标纸病特征提取准确性和算法稳定性;将ASPP空洞卷积加入主干网络SPP中,ASPP可以进一步扩大感受野,使较小目标的特征信息在网络传递时得到保留,解决了小目标信息量不足的问题,进而提高小目标纸病识别的性能。通过自制纸病数据集检测实验,与YOLOv7相比,精确率、召回率及平均精确率均值mAP 0.5分别提升了1.5、2.3和2.1个百分点。     

基于改进CNN的苹果缺陷检测方法研究

目的:解决现有苹果缺陷检测方法存在的精度低、效率差等问题。方法:基于水果图像采集系统,提出一种改进的卷积神经网络用于苹果表面缺陷检测;引入深度可分离卷积代换原网络标准卷积,提高特征提取速度;引入Leaky ReLU激活函数代替ReLU激活函数,提高计算效率和精度;引入全局平均池化替换全连接层,降低网络模型的计算量;并在每层卷积后加入批量归一化层,通过试验与常规方法进行对比分析,验证其优越性。结果:与常规方法相比,所提方法在苹果缺陷检测中具有较高的检测准确率和速度,且模型参数量少,准确率达99.60%,检测速度(每秒帧数)达526,模型参数量为389 072。结论:该苹果缺陷检测方法能有效降低模型参数和检测时间,具有较高的准确率和速度。     

基于改进YOLOX模型的樱桃缺陷及分级检测

目的:实现工业化条件下樱桃的快速分级。方法:采用YOLOX网络对缺陷果进行检测,通过为特征金字塔网络设置适当的融合因子来提高不明显缺陷的检测精度,并将Focal Loss集成到损失函数中;使用YOLOX网络对完好果进行分级,引入注意力机制CBAM来加强网络特征提取。结果:樱桃表面缺陷的平均检测精度为97.59%,大小和颜色分级的平均检测精度为95.92%。结论:改进后的YOLOX网络可明显提升樱桃缺陷及分级检测的精度。     

基于CNN的深层次特征提取纸病辨识方法研究

针对当前纸病检测方法中纸病特征量难分离以及难点纸病特征量难构建的瓶颈问题,提出基于卷积神经网络（CNN）的纸病辨识方法。该方法根据纸病图像的特点设计了纸病检测的CNN结构,在此基础上利用CNN自动提取纸病图像的深层次特征,结合Softmax实现对纸病的辨识。实验结果表明,基于CNN的深层次特征提取纸病辨识方法优于现有的纸病检测方法,能够对包括难点纸病在内的各种纸病进行精确辨识。     

基于改进Faster RCNN的化纤丝缺陷检测

为提高化纤丝生产加工中出现的断线和疵点类缺陷的检测精度，对Faster RCNN算法进行改进。首先，在主干特征提取网络上加入可变形卷积模型，以提高网络对不同缺陷特征的适应性；其次，采用递归特征金字塔(Recursive Feature Pyramid, RFP)结构替换原特征金字塔网络(Feature Pyramid Network, FPN),进行二次特征提取；最后，改进损失函数，采用Rank&Sort Loss(RS Loss)函数替代原分类损失函数，解决化纤丝2类缺陷样本量相差较大问题。对比实验后得出，改进后的方法训练得到的mAP值为84.7%,较初始模型提高了4.3%,可以满足实际生产加工中对化纤丝缺陷的智能检测要求。     

中密度纤维板表面缺陷实时检测系统

中密度板加工生产过程中,表面缺陷检测环节现有方法仍然以人工为主,检测速度慢、效率低。针对中密度纤维板的油污、松软、黑斑、杂物等常见的6类缺陷,设计了一种基于线阵相机的中密度纤维板表面缺陷实时检测系统。提出了一种改进的CenterMask算法,该算法对原有特征提取网络进行了网络改进。在中密度板表面缺陷数据集中的测试结果表明:在检测速度大于6FPS的算法中,改进的CenterMask算法对有着最高的缺陷分割准确率。     

基于改进Faster R-CNN的食品包装缺陷检测

目的：对纸质包装盒缺陷进行准确的识别与定位。方法：应用改进Faster R-CNN的网络模型自动对包装盒缺陷进行检测。对训练集图片进行数据增强并添加噪声，提升模型的训练精度和鲁棒性；将特征提取网络替换为ResNet50，并融合特征金字塔网络（FPN），提高模型多尺度检测的能力；使用K-means++对数据集中缺陷尺度进行聚类，优化锚框方案。结果：改进后的Faster R-CNN模型在测试集上的平均准确率（AP）达到93.9%，检测速度达到8.65帧/s。结论：应用改进的Faster R-CNN模型能够有效检测出包装盒缺陷并定位，可应用于包装盒缺陷的自动检测与分拣。     

基于改进Hough变换的复杂纸页缺陷检测算法

采用传统Hough变换法检测复杂纸页缺陷如褶皱、条痕等直线类特征纸病时,不能有效分辨具有较近斜率或截距的多直线特征.在标准Hough变换的基础上将Hough变换域空间变换为二维图像然后对其进行纸页缺陷特征提取,从而更加精确地检测出褶皱或条痕类纸病.经实验证明,改进的Hough变换在检测精度和时间上都优于标准Hough变换.     

一种基于连通域标记的纸病检测算法

提出了一种基于段的连通域标记处理算法,同时对纸病区域进行连通域标记和形状特征值提取,旨在提高纸病检测的准确率和效率。该算法利用纸病区域为简单连通图像的特点,采用段技术实现了纸病区域的标记处理,探讨了在标记处理同时快速统计与形状特征值计算有关的中间参数的方法,利用标记结果及形状特征值实现了纸病的快速检测。该算法优化了标记处理与形状特征值提取的过程,减少了纸病图像的扫描次数。结果表明,该算法达到了准确、快速的纸病检测效果,且易于扩展到实际的纸病检测系统中。     

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.     

Chlorohydrins of bisphenol A diglycidyl ether (BADGE) and of bisphenol F diglycidyl ether (BFDGE) in canned foods and ready-to-drink coffees from the Japanese market

BADGE.2HCl and BFDGE.2HCl were determined in 28 samples of ready-to-drink canned coffee and 18 samples of canned vegetables (10 corn, 5 tomatoes and 3 others), all from the Japanese market. HPLC was used as the principal analytical method and GCMS for confirmation of relevant LC fractions. BADGE.2HCl was found to be present in one canned coffee and five samples of corn, BFDGE.2HCl in four samples of canned tomatoes and in one canned corn. No sample was found which exceeded the 1mg/kg limit of the EU for the BADGE chlorohydrins. However the highest concentration was found for the sum of BFDGE.2HCl and BFDGE.HCl.H₂O at a level of 1.5mg/kg. A Beilstein test confirmed that all cans containing foods contaminated with BADGE.2HCl or BFDGE.2HCl had at lest one part coated with a PVC organosol.     

European priorities for research to support legislation in the area of food contact materials and articles

A strong science base is required to underpin the planning and decision-making process involved in determining future European community legislation on materials and articles in contact with food. Significant progress has been made in the past 5 years in European funded work in this area, with many developments contributing to a much better understanding of the migration process, and better and simpler approaches to food control. In this paper this progress is reviewed against previously identified work-areas (identified in 1994) and conclusions are reached about future requirements for R&D to support legislation on food contact materials and articles over the next 5 or so years.     

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