复杂背景下人体轮廓及其参数提取

针对基于人体照片的尺寸提取技术对照片拍摄场景限制的问题,提出利用整体嵌套边缘检测深度学习模型实现复杂背景下人体轮廓的提取并进行参数提取分析。以450张不同背景人体照片为原始图像数据集,通过人体轮廓标签图制作与数据增强手段建立了43 200张图片训练集,利用深度学习网络模型进行训练学习并构建最优边缘检测模型;最后选取40名样本作为验证对象,以13个人体比例、角度等参数作为验证参数,对人体轮廓提取值与三维点云测量值进行误差分析。结果表明,本文研究成果能够快速实现复杂背景下人体轮廓的自动提取,且人体轮廓提取值与三维点云测量值的角度参数误差小于2°,比例参数误差小于0.09,为非接触式二维测量技术的进一步研究提供理论依据和技术支撑。     

基于肤色模型的三维人脸重建

针对三维人脸重建时侧面角度的纹理缺失问题,提出了一种基于肤色模型的三维人脸重建方法.该方法利用改进的ASM方法自动提取特征点,通过平面投影和线性组合获取照片对应的深度三维几何信息,将TPS算法变形得到特定三维人脸模型;将RGB空间与YUV空间和YIQ空间进行转换以判定肤色点,通过Gamma矫正侧面角度特征点使其有效落在肤色区域内;最后依据矫正后的肤色点进行纹理映射.实验证明,该方法只用单幅非绝对正面照片即可实现较高真实感的三维人脸重建,并可有效改善侧面纹理缺失的情况.     

基于图像的人体颈肩部三维模型构建

为实现个性化服装在线设计和虚拟试衣,提出一种基于人体正侧面照片的尺寸测量及建模方法.首先结合202名青年女性的三维点云数据确定与人体颈肩部形态相关的8个特征截面层,以各截面层中心点为基准点每隔10°测量角度半径并分析其与截面厚度、宽度之间的关系,建立各截面层的曲线形态规则.然后基于人体正侧面照片进行图像分割以提取人体轮...     

以轻量化为目标的汽车车身优化设计分析

汽车的车身是车的外表,消费者根据车身的外观进行选择。一般情况下,对汽车的设计主要表现在汽车车身方面,因此对汽车车身的研究就相对多点。汽车车身在汽车上占有重要比例,仅车身质量就约占汽车总质量的五分之二。为了满足消费者的需求,在对汽车车身进行优化设计的时候,应当从轻量化入手。文章通过对汽车车身优化设计进行分析,并达到车身轻量化的目的。     

基于散乱点云的三维人体自动测量

为解决Kinect深度相机三维人体扫描重建中人体特征尺寸提取的问题,提出一种基于散乱点云的三维人体自动测量方案。首先,对采集三维点云数据进行预处理,经点云降采样、离群点滤波和表面重建,以及点云坐标转换,进而识别出人体正背面;然后,利用人体几何形状分析法,自动提取人体特征点和特征截面点云;最后,对得到的特征截面点云提取特征边界点,再通过基于凸壳的轮廓线提取算法得到特征边界线,通过三次B样条曲线拟合计算围度、弧长尺寸,利用坐标差值和欧氏距离计算长度尺寸,从而完成对三维人体点云模型的特征尺寸测量。结果表明,该方案受人体体型因素影响较小,所提出的尺寸信息的自动提取方案有效,并符合相关标准中测量精度的要求。     

大众汽车车身连接金相质量监控

车身连接质量是汽车安全的重要指标。要使车身具备良好的车身连接质量,必须从焊装开始对车身生产过程进行严密的监控。一直以来,大众生产的汽车以其皮实耐用著称于世。文章以一汽-大众佛山工厂为例,系统介绍了大众汽车的车身连接质量监控手段。     

汽车焊接夹具的设计研究分析

伴随着国家经济科学的不断提升,我国人民的生活水平也在不断的提高,其中最显著的一个变化就是我国的家庭车辆拥有量在不断的增多。汽车的需求量的提升,在很大程度上对我国汽车的制造质量有了更高的要求。在汽车的车身设计过程中,由于白车车身的制造过程对设计尺寸有非常高的要求。因此在制作白车车身时,对汽车焊接夹具的要求也在不断的提升。汽车车身的尺寸在很大程度上影响着汽车的整体装配,及汽车外形的美观性。因此在汽车车身设计时对汽车夹具的设计就显得非常重视了。文章主要针对汽车焊接夹具的设计进行详细的论述以及分析,希望通过文章的阐述以及分析能够有效地提升我国汽车焊接夹具的设计质量,同时也为我国的汽车装配质量的提升贡献力量。     

基于Ansys的模块化汽车车身有限元分析

模块化汽车正成为新世纪以来的一个发展趋势,汽车车身作为模块化汽车的承载体,其安全性是尤为需要注意的问题。本文使用Catia软件设计一种新型的模块化汽车三维模型,在合理地简化结构后,导入Ansys软件中,建立有限元模型。通过网格划分和载荷施加,完成静力学分析,获得在弯曲和扭转条件下的应力和变形云图。计算得该模块化汽车车身的弯曲刚度为2338.10N/mm,车身的扭转刚度为8245.46 N·m/(°),改新型的模块化汽车的结构设计基本符合要求。     

基于图像处理小麦籽粒长和粒宽的自动测量

干旱高温胁迫是造成小麦减产的主要因素之一.干旱导致小麦籽粒外形特征发生变化,如小麦籽粒干瘪,变小.粒长、粒宽是小麦籽粒重要的形态性状,本文采用边缘检测算法提取出于旱胁迫下小麦籽粒的图像边缘点,再根据图像边缘点,自动检测提取出小麦籽粒的粒长和粒宽特征参数.结果表明,提取出的麦粒图像边缘点精确,对小麦籽粒的粒长与粒宽特征参数的自动估算结果较精确,为定量研究干旱高温胁迫对小麦产量的影响提供了新的手段,为基于计算机视觉的干旱程度自动检测打下基础.     

三维人体照片建模的理论研究与实践

根据从人体不同角度拍摄同焦距的照片 ,通过在不同照片上捕捉实际人体的同一点 ,来得到对这些点的空间定位 ,即“三维坐标”。通过连接许多定位点 ,组成人体模型网 ,实现人体建模 ,从而为三维试衣系统打下良好的基础     

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