基于小波神经网络的帘子布疵点智能识别技术

针对帘子布疵点图像特征,提出了将小波变换和人工神经网络技术应用在帘子布疵点检测上.在融合图像灰度的基础上,经小波变换后再提取分解子图像的特征值,利用BP神经网络进行图像分类.结果表明:对帘子布常见疵点如油污、破洞、抽经、断纬等能比较准确地识别.     

基于机器视觉的帘子布疵点智能识别技术

针对帘子布疵点图像特征,提出了将小波变换和人工神经网络技术应用在帘子布疵点检测的方法。该方法是在融合图像灰度的基础上,经小波变换后再提取分解子图像的特征值,利用BP神经网络进行图像分类。实验结果表明,对帘子布常见疵点如油污、破洞、断经、断纬等能比较准确地识别。     

基亏小波神经网络的帘子布疵点智能识别技术

针对帘子布疵点图像特征,提出了将小波变换和人工神经网络技术应用在帘子布疵点检测上。在融合罔像灰度的基础上,经小波变换后再提取分解子图像的特征值,利用BP神经网络进行图像分类。结果表明：对帘子布常见疵点如油污、破洞、抽经、断纬等能比较准确地识别。     

基于小波熵的织物疵点检测方法

探讨利用小波熵检测织物疵点的新方法。在采用二维离散小波变换对织物图像进行分解的基础上,引入了熵的概念,将小波熵作为织物图像的特征值,把熵值看作系统紊乱程度的度量,由此得到织物图像的小波熵特征值,通过与正常织物经过二维小波变换后提取的小波熵值相比较,熵值大者即认为有疵点存在。通过对不同组织织物和几种典型的织物疵点进行检测,试验结果表明该方法有效可行。     

基于PSO-BP神经网络的织物疵点分类方法

将粒子群优化算法运用于BP神经网络的训练,更合理地确定神经网络的连接权重和阈值,提高解决实际问题的能力。同时将PSO-BP神经网络的模型用于织物疵点的分类中。采用正交小波变换的方法对织物图像进行单层分解,并提取水平和垂直2个方向的子图像,分别代表织物的纬向和经向纹理,然后计算其经、纬向的能量、方差、熵等特征值,做为神经网络的输入值。将PSO-BP神经网络与BP神经网络分类的结果相比较,表明PSO-BP神经网络能够取得较好的效果。     

基于BP神经网络织物疵点检测识别

根据疵点的特征对简单的织物疵点进行识别,先采用直方图均衡化、小波分解、二值化等方法对织物图像进行一系列的预处理,然后提取出织物疵点的特征值,再利用3层BP神经网络对织物疵点进行训练识别分类,试验结果表明识别率达95％。     

基于小波分析与纹理能量变换的织物疵点检测

为了准确检测织物疵点,将含疵点织物图像进行二维小波分解,在小波分解后的经向和纬向子图上将图像分成大小相同的矩形局部重叠窗口,对矩形窗口进行laws纹理能量变换,并将变换结果与给定的阈值进行比较,进而检测和识别出疵点.试验证明,该方法对素色织物的断经、缺纬具有快速、准确的检测效果,也可以检测双经、双纬等疵点.     

基于改进的小波分解织物疵点检测

采用小波分解的改进方法，运用二维离散小波变换进行分解，有效地从图像中提取信息，分析织物的纹理特征并进行相应处理，实现目标图像的特征提取和输入LMBP神经网络进行学习训练。实验结果表明，对油污、破洞、断经、断纬能比较准确地识别和定位，可快速有效地进行织物疵点检测。     

小波分析在织物缺陷检测中的应用

对于织物缺陷的检测，可以使用多种不同的图像处理技术．而具有多分辨特性的小波变换是一种分析图像的新方法，它的变尺度特性与人类视觉中的空间频率多通道相吻合．使用小波分析的方法对3种织物缺陷进行检测分类．首先将织物图像进行3层小波分解，然后把小波分解后的图像灰度值作为特征参数输入到BP神经网络进行检测识别，实验结果表明，用这种方法识别织物缺陷识别率可达到98％。     

基于人工神经网络的织物疵点检测

根据疵点的特征对常见织物疵点进行了简单的划分。采用直方图均衡化、二值化、中值滤波、腐蚀和膨胀等方法对织物图像进行一系列的预处理，对织物疵点的特征参数进行提取，利用人工BP神经网络来判别疵点的类别并进行分类。结果表明，利用BP神经网络识别织物疵点并进行分级是行之有效的。     

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.     

Textural Properties of Cold-set Gels Induced from Heat-denatured Whey Protein Isolates

A 9% whey protein (WP) isolate solution at pH 7.0 was heat-denatured at 80°C for 30 min. Size-exclusion HPLC showed that native WP formed soluble aggregates after heat-treatment. Additions of CaCl2 (10–40 mM), NaCl (50–400 mM) or glucono-delta-lactone (GDL, 0.4–2.0%, w/v) or hydrolysis by a protease from Bacillus licheniformis caused gelation of the denatured solution at 45°C. Textural parameters, hardness, adhesiveness, and cohesiveness of the gels so formed changed markedly with concentration of added salts or pH by added GDL. Maximum gel hardness occurred at 200 mM NaCl or pH 4.7. Increasing CaCl2 concentration continuously increased gel hardness. Generally, GDL-induced gels were harder than salt-induced gels, and much harder than the protease-induced gel.     

Occurrence of bisphenol-F-diglycidyl ether (BFDGE) in fish canned in oil

The levels of bisphenol-F-diglycidyl ether (BFDGE) were quantified as part of a European survey on the migration of residues of epoxy resins into oil from canned fish. The contents of BFDGE in cans, lids and fish collected from all 15 Member States of the European Union and Switzerland were analysed in 382 samples. Cans and lids were separately extracted with acetonitrile. The extraction from fish was carried out with hexane followed by re-extraction with acetonitrile. The analysis was performed by reverse phase HPL C with fluorescence detection. BFDGE could be detected in 12% of the fish, 24% of the cans and 18% of the lids. Only 3% of the fish contained BFDGE in concentrations considerably above 1mg/kg. In addition to the presented data, a comparison was made with the levels of BADGE (bisphenol-A-diglycidyl ether)analysed in the same products in the context of a previous study.     

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.     

Contribution of European research to risk analysis

The European Commission's, Quality of Life Research Programme, Key Action 1—Health, Food & Nutrition is mission-oriented and aims, amongst other things, at providing a healthy, safe and high-quality food supply leading to reinforced consumer confidence in the safety of European food. Its objectives also include the enhancing of the competitiveness of the European food supply. Key Action 1 is currently supporting a number of different types of European collaborative projects in the area of risk analysis. The objectives of these projects range from the development and validation of prevention strategies including the reduction of consumers risks; development and validation of new modelling approaches; harmonization of risk assessment principles, methodologies, and terminology; standardization of methods and systems used for the safety evaluation of transgenic food; providing of tools for the evaluation of human viral contamination of shellfish and quality control; new methodologies for assessing the potential of unintended effects of genetically modified (genetically modified) foods; development of a risk assessment model for Cryptosporidium parvum related to the food and water industries; to the development of a communication platform for genetically modified organism, producers, retailers, regulatory authorities and consumer groups to improve safety assessment procedures, risk management strategies and risk communication; development and validation of new methods for safety testing of transgenic food; evaluation of the safety and efficacy of iron supplementation in pregnant women; evaluation of the potential cancer-preventing activity of pro- and pre-biotic ('synbiotic') combinations in human volunteers. An overview of these projects is presented here.