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经编CAD系统是用于设计和开发经编针织物的重要工具。本文从织物设计、织物仿真及织物三维虚拟展示3方面详细地阐述了国内外经编CAD系统的研究进展情况,同时介绍了国内外经编CAD系统的应用现状,主要包括德国Procad系统、Design Scope系统,西班牙Lace Drafting Software SAPO系统,日本武村提花设计系统,江南大学WKCAD系统,武汉纺织大学HZCAD系统等。最后,分析了经编CAD技术的发展趋势,认为设计系统的功能将进一步拓展,仿真技术进一步完善,CAD系统趋向于网络化和智能化。 相似文献
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为了解决轴向经编针织物计算机辅助设计方面的不足并且最终实现其快速设计,本文针对轴向经编针织物的CAD设计与仿真功能进行了研究。在深入了解轴向经编针织物生产工艺的基础上,采用实验的方法测量了织物结构的尺寸,建立了轴向经编针织物的CAD设计模型,其中包括地组织模型和铺纬组织模型;重点研究并建立了轴向经编针织物的纱线与线圈的二维仿真模型,以及玻璃纤维衬纱、线圈的三维仿真模型;以Visual C++ 为开发工具,并且结合OpenGL(Open Graphics Library)图形库,最终在WKCAD4.0系统中实现了轴向经编针织物的CAD设计与仿真功能。 相似文献
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为了采用计算机技术更真实地模拟经编组织中线圈的形态结构,通过观察各种经编针织物的线圈结构,分析由纱线张力所引起的线圈偏移规律,得出了线圈偏移理论和计算公式。该理论假设同一枚针上的线圈偏移量是该针上所有线圈偏移量的累加值。结合此偏移理论,在已建立的经编线圈三维模型的基础上,修正了定义线圈三维结构的部分控制点坐标。最后结合Visual C+ +. NET编程语言和OpenGL工具,成功实现了各类单针床经编针织物的计算机三维仿真。仿真图片与真实织物对比,在形态结构上具有较高的相似度。 相似文献
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预定向增强针织物是一种在复合材料领域里广泛应用的针织结构,它们的线圈几何结构对复合材料的力学性能有很大的影响.文中介绍了针织物线圈结构模型的研究历史,对经编和纬编预定向增强针织物线圈结构模型进行了详细的分析讨论.经编包括:衬纬经编线圈结构模型、双轴向增强经编织物线圈模型、MWK织物(多轴向增强经编织物)的单胞分析模型和经编多轴向增强结构的三维模型;纬编包括:MBWK织物(纬编双轴向多层衬纱织物增强复合材料)的线圈几何模型和用NURBS方法建立MBWK织物的线圈结构模型. 相似文献
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经编组织的三维仿真与动态实现 总被引:3,自引:2,他引:1
为了对经编针织物的结构特征和外观效果进行预测,通过分析普通经编针织物的线圈结构,对O Goktepe的三维实体纱线模型进行了改进,得出线圈三维结构尺寸。利用非均匀有理B样条(NURBS)曲线和曲面原理,建立经编组织成圈线圈和衬纬线圈的三维实体模型;运用这些三维线圈模型,结合经编组织的垫纱数码,实现各种形态线圈的自由连接;最后运用Visual C++和Open GL开发工具,将织物的光照和材质因素引入织物三维结构模型中,成功实现对单梳和双梳经编组织的三维模拟。 相似文献
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基于NURBS曲面的经编针织物三维模型 总被引:1,自引:1,他引:0
为使经编针织物CAD系统具有更真实的模拟效果,给设计人员提供准确的工艺设计方案,使用NURBS曲线和曲面的方法建立经编针织物的三维结构模型,并利用保形保凸反算插值的方法,在基本型值点的基础上重构表示经编线圈曲线模型的控制多边形,精确地确定空间纱线的实际形态和位置,描绘出精确的空间曲线。借助于Visual C++和Open GL开发工具,在计算机上实现了经编针织物的三维仿真。由实现的基本经编针织物效果图可以知道,这种模型能达到较好的仿真效果。 相似文献
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针对目前脖套结构单一,裁剪缝制加工工序多且有裁剪损耗等问题,在分析研究人体头颈部位尺寸数据的基础上,结合经编全成形原理进行全成形脖套款式结构设计与开发。首先确定基础纸样结构,在纸样上进行穿戴部位设计与结构分区,对于口鼻部位进行一体成形的双层织造结构开发,通过贾卡变化组织定位设计实现双层结构局部开口;之后在经编针织物CAD系统中进行贾卡组织设计,建立工艺模板并进行织物结构仿真;最后应用Style 3D软件进行经编全成形脖套的三维建模与虚拟展示。研究结果表明,一体成形的双层结构可通过贾卡变化组织实现,通过经编全成形织物的二维仿真与三维虚拟展示可快速预览开发织物的穿戴效果,为实现经编全成形新品的快速开发提供有效途径。 相似文献
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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. 相似文献
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John Gilbert Catherine Simoneau David Cote Achim Boenke 《Food Additives & Contaminants》2000,17(10):889-893
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. 相似文献
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Sophie Guillot Laurence Peytavi Sylvie Bureau Renaud Boulanger Jean-Paul Lepoutre Jean Crouzet Sabine Schorr-Galindo 《Food chemistry》2006
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. 相似文献
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Jesus Simal-Gandara Miguel Sarria-Vidal Arjen Koorevaar Rinus Rijk 《Food Additives & Contaminants》2000,17(8):703-711
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. 相似文献
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M. S. Garcí a-Falc n J. Simal-G ndara S. T. Carril-Gonz lez-Barros 《Food Additives & Contaminants》2000,17(12):957-964
A simple, rapid and inexpensive method has been developed for the determination of benzo[a 相似文献
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H. J. Van Den Top A. Boenke P. A. Burdaspal J. Bustos H. P. Van Egmond T. Legarda A. Mesego A. Mourino W. E. Paulsch C. Salgado 《Food Additives & Contaminants》2001,18(9):810-824
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. 相似文献
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《肉类研究》2014,(2)
<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 相似文献
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《印刷工业》2014,(11):95-95
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%. 相似文献
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《印刷工业》2014,(8):103-103
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 相似文献