牛仔面料残留起拱现象与摩擦因数关系的模拟

通过多元线性回归的方法,对牛仔面料的残留起拱现象,如残留起拱高度、残留起拱体积和残留起拱回复性等进行模拟分析。根据观察到的现象可得出,牛仔面料的起拱残留现象和所测试的摩擦因数之间有较高的关联度(即较高的回归系数),如纱线与纱线之间的摩擦、纱线与金属之间的摩擦及金属与织物之间的摩擦等。研究还发现,残留起拱性能可利用摩擦因数的回归方程进行预测。     

基于激光测量的机织服装起拱性客观评价

为研究客观、精确的服装穿着起拱性测试与评价方法,将20种机织物制作成裤筒进行穿着起拱实验。拍照保存织物的起拱形态,并运用激光扫描仪获取起拱部位的三维点云数据。对获取的数据进行预处理及特征提取,得到三维指标:起拱高度、起拱体积、经纬向最大起拱率;并提取起拱图像的二维灰度共生矩阵参数用于对比分析。经过对12块机织物的验证表明:起拱体积与主观评价等级的相关系数最高;本文提出的经纬向最大起拱率与起拱等级的相关性较好,其差值可用于判断起拱形状;利用激光扫描得到的三维指标预测起拱等级的准确率高于二维指标,且可克服机织物花纹图案、组织结构等对其的影响。     

商务用针织面料的起拱变形研究

选取了15种不同规格参数的商务用针织面料,采用定拱高的往复匀速变形运动模拟织物穿着过程中肘部与膝部的起拱过程,测定织物的起拱回复残留高度,分析织物的抗起拱性能。采用线性回归方法,分析了影响织物抗起拱性能的因素。研究结果表明:织物中氨纶质量分数与织物面密度对其抗起拱性能影响较显著,织物中氨纶的质量分数越大,织物面密度越小,其抗起拱性能越好。织物的厚度与密度对其抗起拱性能影响不显著。     

基于小波分析的毛料服装穿着起拱性客观评价

以16块含毛纯色机织试样为研究对象,将其制作成裤子进行实际着装起拱,在测量起拱高度的同时,对起拱程度还进行了专家5级评分法和排序法评价,采用对起拱图像进行小波分析的客观评价方法,提取小波细节系数标准差作为客观评价指标。研究显示:小波分解4层时垂直方向的细节系数标准差SV4无论与主观评价结果还是与起拱高度都有较好的相关性,因此可以通过计算图像的细节系数标准差来预测专家主观评价的结果以及起拱高度,具有客观、高效、准确的优点。     

重磅真丝绸起拱性能的测试研究

采用自制的起拱测试装置,对重磅真丝绸的起拱高度进行了测试和分析,得出了重真丝绸的起拱高度与织物重量,织物重量与织物紧度间的回归关系式,为重碲真丝绸抗起拱性的适合重量和紧度设计提供了数据支持。     

基于图像的织物速度非接触测量方法

织物运行速度是纺织工业中的重要工艺参数,传统测量方法采用接触式测量。为避免织物与导轮之间滑转产生测量误差,本文根据织物表面纹理灰度信息随机性的特点,通过织物表面纹理图像实现了非接触式的速度测量。利用高速线阵CCD相机采集织物表面纹理灰度信息,相邻两帧图像具有波形相似且有一定的空间位移,采用互相关算法及其改进算法计算出空间位移,结合连续两帧时间计算出织物运行速度。为提高计算准确度采用高斯曲线拟合互相关函数的峰值并给出拟合公式,得到了亚像素级的运动速度。通过实验验证了算法的可行性及其精度。     

Peirce平纹机织物结构模型的计算精确度

为提出一种可估计任意机织物结构理论模型精度的思路,利用Peirce织物结构理论计算平纹织物纱线的几何形态。用Keyence数码显微镜非破坏性地实际测量织物的关键点位置,并利用保形3次B样条曲线模拟织物结构。采用离散Fréchet距离进行判别理论计算的纱线构形曲线和实测模拟的纱线构形曲线的相似性程度。计算两条曲线上对应波峰点、波谷点及相邻波峰点与波谷点的离散Fréchet距离差的绝对值,得到一个可认为曲线相似时的阈值 ,并与织物厚度相比较,提出纱线中心线形状相似度的概念。阈值 越小,则相似度越高,织物结构模型计算的精确度越高。通过MatLab应用程序,对两种平纹组织三维重建织物结构模型的相似性进行了分析并计算出样品1和样品2经、纬纱的相似度值分别为90%,86%,82%,94%。     

基于图像处理的机织物密度的高精度识别

通过对机织物图像和扫描仪精度的探讨,选择用扫描仪垂直扫描得到高分辨率的机织物表面反射图像,并提出采用特定的图像尺寸对织物图像进行处理。利用纱线间隙定位法对织物图像进行纠偏预处理。在处理后织物图像的亮度投影曲线中,通过区域排查的方法确定纱线间隙的位置。再对纱线间隙的距离依次检查,得到纱线间隙距离的准确平均值,最终得到织物的密度。实验证明,所得结果最高误差为0.07%,准确度较高。     

织物弯曲性能测试新方法

斜面法是测试织物弯曲性能最普遍的方法,但是斜面法本身有一定的局限性。针对这种情况,制作出了一种新弯曲性能检测仪,由自动送样装置和图像处理的软件程序两部分组成,来测试织物的弯曲性能,文中称之为新方法。分别测试了20种织物的弯曲性能,得到了两种方法的伸出长度读数,并用积分计算了弯曲状态下曲线的长度。结果表明:两种方法得到的伸出长度读数之间,积分算法得到的长度与伸出长度读数之间都具有高度线性相关关系,说明积分算法的结果可以表征新方法的伸出长度;两种方法的弯曲刚度之间相关系数的平方R2=0.970,为高度正相关,说明提出的测试织物弯曲性能的新方法是可行的。     

Calculated accuracy of Peirce's plain woven fabric model for geometric structure of plain woven fabrics

为提出一种可估计任意机织物结构理论模型精度的思路,利用Peirce织物结构理论计算平纹织物纱线的几何形态.用Keyence数码显微镜非破坏性地实际测量织物的关键点位置,并利用保形3次B样条曲线模拟织物结构.采用离散Fréchet距离判别理论计算的纱线构形曲线和实测模拟的纱线构形曲线的相似性程度.计算2条曲线上对应波峰点、波谷点及相邻波峰点与波谷点的离散Fréchet距离差的绝对值,得到一个可认为曲线相似时的阈值ε,并与织物厚度相比较,提出纱线中心线形状相似度的概念.阈值ε越小,则相似度越高,织物结构模型计算的精确度越高.通过MatLab应用程序,对2种平纹组织三维重建织物结构模型的相似性进行分析并计算出样品1和样品2经、纬纱的相似度值分别为90％、86％、82％、94％.     

Analytical studies on woven fabrics’ bagging performance affected by the material,yarn, and fabric parameters

The present work focuses on investigating the bagging behavior of woven fabrics produced from viscose and polyester/viscose yarns. In this paper, the bagging deformation – in terms of different bagging parameters (bagging resistance, bagging fatigue, bagging hysteresis, and residual bagging hysteresis) – has been interpreted by fabric’s physical and mechanical properties which were obtained from FAST system. The statistical analysis revealed that there is a significant correlation between the bagging parameters. Also, it was concluded that the samples’ physical and mechanical properties correlate significantly with bagging parameters. Additionally, the effects of four different variables such as material type, spinning system, weave pattern, and weft density on bagging parameters have been studied. Considering the high correlations between all the bagging parameters, it was decided to analyze only the parameter bagging fatigue in this paper. The results showed that all the fabric variables except the parameter weft density have significant effects on bagging fatigue performance.     

A review on fabric bagging: the concept and measurement methods

Fabric bagging is a three-dimensional permanent deformation which can deteriorate aesthetical appearance and mechanical properties of garments. This review presents a brief look at the concept of bagging deformation consisting basic definitions, theories and modelling, objective and subjective evaluation and the parameters affecting fabric bagging. The effects of both fabric structural properties and bagging test parameters have been also explored. A thorough knowledge of bagging measurement by different laboratory tests such as unidirectional tensile, bursting strength, ball penetration tests and devices resembling an arm having an elbow point for simulating human movements in static or dynamic conditions was reviewed in details.     

Modeling the bagging behavior of worsted fabrics using response surface methodology

In this paper, we have studied the effect of a number of loading cycles on fabrics bagging behavior, and then investigated the influence of factors such as sample weight, test speed, and sphere diameter on the worsted fabrics bagging behavior using response surface method (RSM). Six worsted fabric types with different weights were prepared and then the bagging properties of these fabrics were measured using a newly developed test method. Bagging parameters including bagging force, work, fatigue, resistance, hysteresis, and residual height are calculated. Then, a statistical model (RSM) was used for the experimental plan (with these factors) to determine the runs of an experiment (or selected points). The experimental results showed that sample weight and sphere diameter have a significant effect while test speed has no significant effect on the bagging parameters. Also, the fitted models of bagging parameters are obtained and coefficient effects are estimated.     

Study of knitting factors contribution on residual bagged fabric behaviour

The aim of this work is to analyse and evaluate the contribution of some knitting machine and yarn structure parameters on the residual bagging height using an experimental Taguchi design method. Besides, the effects of each input parameter as well as their interactions are discussed. In our experimental field of interest, the results show that the most important factors are the tightness factor and the gauge; thanks to their most influential contributions represent on the residual height behaviour of bagged fabrics. Based on a comparative analysis, our findings show that yarn composition affects widely the residual bagging height because it presents a non-negligible contribution on the height of bagged samples. However, amongst the overall investigated interactions between input parameters, only some influential ones give more explanation about how to decrease the residual bagging height of knitted fabrics.     

Sheet forming of woven fabric composite by combined cyclic stretch and deep drawing

The manufacturing of composites often requires transformation of 2-D fabrics into various structural 3-D shapes through preform processing without over straining of the yarns or wrinkling. Sheet forming of woven fabric composite by combined cyclic stretch and deep drawing was suggested. In order to prevent the wrinkling, the geometrical and mechanical properties of fabric should be chosen to get the final form of the prepregs beforehand. Geometrical investigation of the final bagged form dimensions are based on geometrical aspects of the wrapping of the fabric. In this study, an approach was proposed to form the reinforcement fabric composite through the dynamic bagging of the fabric by the application of cyclic stretching on the fabric during formation of 3-D reinforcement structure in hot environment. The dimensions of the flat fabric were calculated and the parameters of the forming process analyzed in two cases: hemisphere and flat top cone shape.     

蜜柚套袋种植中氯硝胺的迁移规律研究

采用气相色谱-串联质谱法检测套袋纸及蜜柚中氯硝胺的含量,并通过田间试验研究了氯硝胺从五种套袋纸向蜜柚不同部位的迁移规律。结果表明四种含有氯硝胺的套袋纸处理的蜜柚全果中氯硝胺的残留浓度随着套袋时间的延长逐渐升高,到第40 d达到最高值。以第70 d蜜柚正常成熟采收为计,全果中氯硝胺的最终残留浓度与套袋纸中氯硝胺的初始含量的相关关系符合预测方程y=-0.048×e^{（-x/26.156）}+0.048,当全果中氯硝胺的最终残留浓度为0.01 mg/kg时,套袋纸中氯硝胺的初始临界含量为6.126 mg/kg。蜜柚套袋全过程中,五种套袋蜜柚果肉均未检出氯硝胺残留。通过提前10 d摘袋,全果中氯硝胺的残留量可降低23.8%。本研究为揭示蜜柚中氯硝胺残留污染的来源提供了科学依据,为今后蜜柚套袋种植以及套袋纸生产管理具有重要的指导意义。     

套袋对清见橘橙果实蔗糖代谢的影响

研究6 种果袋对清见橘橙果实可溶性糖含量及蔗糖代谢关键酶活性的影响。结果表明：不同果袋对清见橘橙果实可溶性糖含量的影响不同,单层果袋显著提高了果实的可溶性糖含量。果实成熟时,套白色单层无纺布袋的果实蔗糖含量最高,套黄色单层袋和白色单层袋的果实果糖含量均最高,套白色单层袋的果实葡萄糖含量最高。单层果袋提高了果实中性转化酶（NI）、蔗糖合酶（SS）和蔗糖磷酸合酶（SPS）的活性,以无纺布袋最为明显,而双层果袋对NI、SS、SPS活性的影响在多数测定点差异不显著。酸性转化酶（AI）活性随着果实的成熟而降低,套袋对AI活性的影响不显著。综上可知,单层果袋通过提高NI、SS、SPS的活性来提高糖含量,因此清见橘橙宜选择具有一定透光率且色泽浅的单层果袋。     

套袋对芒果果实采后品质和后熟的影响

在芒果(Mangifera indica L.cv.Zihua)的生长期内,分别用纸袋和无纺布袋进行套袋处理,以不套袋果实作为对照。果实采收后于20℃,85%～95%RH的环境下进行贮藏,并定期取样进行观察测定。结果表明,生长期套袋的"紫花"芒果果实果面的锈斑发生率和锈斑指数都比对照果实低,套袋对芒果果实的可溶性固形物和可滴定酸含量、硬度、呼吸强度几乎没有影响,但套袋处理更容易使果实着色。布袋的效果优于纸袋。     

基于图像处理的织物保形性检测

为更加全面、准确地评价织物保形性,开发了能够模拟织物在日常使用中被压皱后展平的恢复过程动态检测系统.通过检测系统获取织物折痕回复的视频序列,利用程序提取出各时刻的单帧视频图像,然后依次对图像进行预处理、二值化处理与细化处理,最后提取出反映织物保形性的指标,包括顶角、顶高、保形面积.实验结果表明:在折痕回复阶段,随时间延...