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1.
Bra cup moulding is currently a remarkable process in the production of seamless intimate apparel. The process is highly complex, time-consuming and error-prone due to the large variations of foam and lamination properties, cup styles and sizes, and geometric features of graduated padding. In particular, the three-dimensional (3D) geometric shape of foam cups is difficult to assess accurately because they are very soft and readily deform. In cases that involve fitting problems, shape modifications of the mould head and determination of the optimal moulding conditions have undergone repeated trials and errors. There is limited knowledge about the effects of foam properties and cup parameters in the controlling of moulding conditions. This study adopts a parameterization-based remesh algorithm method to evaluate the 3D shapes of the convex surface of scanned cup samples. The shape conformity of the cup is quantified in accordance to the corresponding mould head. In this respect, the moulding conditions that would achieve the most desirable geometric shapes of bra cups can be accurately and objectively demonstrated. Based on moulding experiments with 6 types of polyurethane (PU) foam materials, empirical equations that associate the cup shape conformity and the shape deviations from selected cup sectional curves are established. Through the use of non-linear regression models, the shape conformity of the moulded cups can be predicted by moulding conditions with reasonable accuracy. The shape conformity provides effective guidelines for quality assurance and improves production efficiency of bra cup moulding. Moreover, thermal-mechanical properties, such as compressive strain and softening temperature obtained from thermomechanical analysis (TMA) scans, provide a good understanding of cup shape conformity and determine the lowest moulding temperature at initial trails of the bra cup moulding process. Surprisingly, in pliable foams, the cup size does not have an apparent effect on the moulding conditions to achieve optimal cup shape conformity. The results reveal that the moulding conditions for sizes 34B and 34D could remain the same for pliable foam materials. Nevertheless, in the case of more rigid foams, a higher moulding temperature is required to achieve a desirable cup shape for size 34D as more energy is required for the heat-setting of foam materials with higher proportions of hard segments at the moulding of a larger cup size in anticipation of larger deformations.  相似文献   

2.
Seamless knitting, as a new technology, has a great potential in the development of lingerie products. Bra knitting using seamless knitting technology is a difficult engineering problem due to the lack of knowledge on how to achieve proper underband tension and cup strain for optimal comfort and shape. In this study, we aim at identifying the key knitting parameters and experimentally investigating their relationships with the knitted bra tension. The knitting parameters under investigation were loop density, elastic yarn tension, cover yarn tension and nylon yarn tension. Factorial experimental design was used to explore the most significant factors affecting the underband tension and cup strain of seamless knitted bra. The results show that the loop density and elastic yarn tension were the two main factors affecting the underband tension. The cup strain was mainly affected by the loop density. Empirical prediction equations have been established to estimate the underband tension and cup strain from knitting parameters.  相似文献   

3.
Seamless knitting for making bras is a novel approach. The fitting evaluation of these products remains unknown and there is limited knowledge about the effects of knitting parameters on the bra tension. This study developed 3 styles of seamless knitted bras with various loop length and elastic yarn tension based on a 22 full factorial experimental design with one additional centre level. Therefore, a total of 3 × 5= 15 new seamless bra samples have been knitted. The skin pressure exerted by the new bras was compared with 4 commercial bras including 2 “cut and sewn” wired bras and 2 seamless knitted bras. Six women subjects of breast size 75B* in our newly developed breast sizing system were invited to wear all the bra samples. The skin pressure exerted by the bra was measured by the Novel pliance-X pressure sensors on 11 body positions. The results indicated that newly developed seamless bras showed lower pressure than the commercial bras, but had a considerably higher pressure at the cup base point. The new seamless bras with the largest loop length presented the lowest pressure values. Furthermore, empirical equations were established to predict 2 critical pressure points at “apex” and “side bottom band” from two major knitting parameters. This study provides the new knowledge of seamless knitted bra fitting and the resulted bra pressure, as well as some guidelines for seamless knitted product design and manufacturing.  相似文献   

4.
Background odors produced by plants in the environment can interfere with the response of insects to a point-releasing attractant, especially when their compositions overlap. In this study, a series of binary choice tests was conducted in a wind tunnel to investigate whether background odors emitted from cherry, blueberry, blackberry, or raspberry fruits would affect the level of Drosophila suzukii (Matsumura) attraction to its symbiotic yeast, Hanseniaspora uvarum (Niehaus) (Saccharomycetales: Saccharomycetaceae). Whether an increase in the intensity of background odors would affect the attractiveness of H. uvarum to D. suzukii was also investigated, either by increasing the number of cherry or raspberry fruit per cup or by increasing the number of fruit cups surrounding the cup baited with the yeast. In wind tunnel assays, background fruit odors interfering with D. suzukii attraction to the yeast varied among fruit types. Raspberry odor inhibited the attractiveness of H. uvarum to the fly the most, followed by blackberry odor, whereas cherry and blueberry odors had no significant impact on the attraction. An increase in the intensity of odors by adding more cherry or raspberry fruit per cup did not increase the impact of fruit odor on the attraction; however, adding more raspberry cups around H. uvarum linearly decreased its attractiveness, suggesting that background host fruit abundance and likely increase in host odor may influence D. suzukii attraction to yeast odor depending on host species.  相似文献   

5.
刘龙  王胜  屈哲  杨晨  张润锴  余永昌 《大豆科学》2019,38(2):291-297
小区大豆播种机田间作业时不同品种大豆需要人工换种,为解决换种效率低的问题,研究设计一种新型的自动转盘式小区大豆播种机自动供种装置。整个供种装置采用转盘式的圆形种盘与种杯组合的方式,使用PLC控制工作过程,完成小区大豆播种机播种过程中的自动换种。该自动供种装置包括机械部分和电控部分,其中机械部分由种杯、种盘、底座、安装支架等组成。试验对种杯进行了理论分析及结构设计,对电控部分进行了硬件选型及参数确定,并设计直流步进电机的控制软件。通过该自动供种装置进行室内台架试验,结果表明:种杯的偏移量合格率最大为99.6%,种子无破碎供种合格率最大为99.836%,具有较好的准确性和可靠性,符合小区播种机上种的农艺要求。  相似文献   

6.
CAD课程是高等学校本科四年制车辆工程专业学生选修的相关计算机应用领域的课程。CAD作为一种现代化的工程设计手段已经步入了工程设计的各个领域。该类课程的目的在于让学生对计算机在绘图与设计领域中所起的作用进行充分的了解,掌握使用计算机绘图与设计的方法。通过对该类课程的学习和上机实训操作,学生能够熟练掌握CAD软件二维、三维零件设计的理论及应用,提高计算机二维、三维辅助设计的能力,为今后进行零件设计和解决工程实际问题提供必要的CAD知识和设计方法。  相似文献   

7.
目前化学农药的缺点日益突显,研发环保的生防菌剂是当前绿色安全的一种方法,筛选具有抑制橡胶树炭疽病的生防菌株,为研发新型生防菌剂储备资源。本文采用组织培养法分离纯化橡胶树内生菌,平板对峙筛选拮抗菌株;通过菌株培养特征、生理生化、根据16S rRNA和gyrA基因序列构建系统发育树确定其分类地位;采用平板对峙法研究内生菌株的抗菌持久性、稳定性、广谱性;采用牛津杯法研究拮抗内生菌对杀菌剂的敏感性。从橡胶树健康的根组织中分离得到4株对橡胶树炭疽病具有抑制作用的细菌(Bac RZS3D4-1、Bac RZS3D4-2、Bac RZS3D4-3、Bac RZS3D4-4),系统发育树分析结果显示这4株细菌与解淀粉芽孢杆菌(Bacillus amyloliquefaciens)亲缘关系很近,且培养性状和生理生化特征也与解淀粉芽孢杆菌相似。这4株内生菌的抗菌持久性强,抗菌稳定性好;对尖孢炭疽菌(Colletotrichum acutatum)DFMP1E和MLZZP3、小孢拟盘多毛孢(Pestalotiopsis microspora)MF375898均有较强的抑菌能力,对茄类镰刀菌(Fusarium solani)XJ160901的抑制作用较弱;对多菌灵、异菌脲、百菌清、苯醚甲环唑4种杀菌剂均不敏感,有望开发为生防菌剂。  相似文献   

8.
易位是一种常见的染色体变异类型,在小麦进化及育种进程中发挥了较大的作用。为给小麦育种改良提供新的材料,本研究采用非变性原位杂交(ND-FISH)技术,对八倍体小偃麦与普通小麦品种川麦107杂交产生的高代稳定品系进行分析鉴定。结果发现,4个小麦品系TC、19Y-145、19Y-185和19Y-200分别在7B与3D、2D与3B、7B与4D和3B与3D染色体之间发生了相互易位。在TC、19Y-145中,易位断裂点发生在着丝粒区域,分别形成3DS·7BS和3DL·7BL、2DS·3BS和2DL·3BL相互易位染色体。在19Y-185中,易位断裂点发生在7B染色体的长臂和4D染色体的短臂上,构成4DS-7BS·7BL和4DL·4DS-7BL相互易位染色体。在19Y-200中,易位断裂点发生在3B染色体和3D染色体的长臂上,形成3DL-3BS·3BL和3DS·3DL-3BL相互易位染色体。在这4种易位类型中,除3B与3D染色体易位有报道外,其余3种均为新的易位类型。推测这些染色体相互易位类型可能与四川独特的环境气候有关。本研究获得的小麦染色体有益相互易位类型,不仅能够拓宽小麦的遗传基础,也可为研究小麦的染色体变异和种质创新提供新的材料。  相似文献   

9.
Three-dimensional (3D) structures of a rice grain were visualised by means of the new 3D visualisation technique. This technique produced a virtual 3D model of a sample material by stacking a set of captured sequential section images in a personal computer (PC); thus, the internal structure of the sample material was constructed. The 3D structure of an immature rice seed, e.g. the formation of the vascular bundle, was visualised by reconstructing a virtual 3D model from sequential captured images of the cut-off face. The 3D structure of a brown rice grain, e.g. the location of the central line, was also visualised by means of reconstruction from captured images of stained sequential sections.  相似文献   

10.
Genes are continually being created by the processes of genome duplication (ohnolog) and gene duplication (paralog). Whole-genome duplications have been found to be widespread in plant species and play an important role in plant evolution. Clearly un-overlapping duplicated blocks of whole-genome duplications can be detected in the genome of sequenced rice (Oryza sativa). Syntenic ohnolog pairs (ohnologues) of the whole-genome duplications in rice were identified based on their syntenic duplicate lines. The paralogs of ohnologues were further scanned using multi-round reciprocal BLAST best-hit searching (E〈e^-14). The results indicated that an average of 0.55 sister paralogs could be found for every ohnologue in rice. These results suggest that small-scale duplications, as well as whole-genome duplications, play a significant role in the two duplicated rice genomes.  相似文献   

11.
利用浸种法将外源DNA导入玉米自交系,后代产生了多种多样的变异类型,变异性状十分丰富,主要包括株高、穗位高、叶片数、叶片形状与颜色、叶片的长度与宽度、光合叶面积、百粒重和生育期等。这些变异性状有的具有供体性状,有的产生新的性状,并且在D3代趋向稳定。从D0到D3代连续4代田间性状观察发现,变异植株的株高、穗位高均变矮,叶色浓绿。对D3代稳定株系的可溶性糖含量进行测定分析,结果表明,可溶性糖含量都有所提高。该方法为改良玉米品质,创造玉米新种质提供一条新的途径。  相似文献   

12.
The aim of the present work was to explore the suitability of two kinds of bean with typical protein quality and different starch structure to produce moulded specimens by compression. In this work we analysed the possibility of forming new plastic materials from two kinds of bean preparations; with different protein content, in the presence or absence of inherent cellulose material and other biopolymer such as starch. Significant differences were determined in the fine structure of glucopolysaccharides isolated from the different types of bean. Complete moulding of the specimens took place at 20 MPa at a temperature not higher than 140°C, for 7 min. The mechanical properties of the moulded plastics based on soluble protein black bean (BP) were superior in elongation, tensile strength and low water absorption than the soluble protein white bean (WP) variety. However, the addition of boric acid 3% (w/w, in total batch basis) to white bean plastic materials was effective in improving slightly the mechanical properties in the case of their whole flours products (WWF). The gamma radiation was effective to reduce water absorption only in plastics materials with cellulose–starch content (BWF, WWF) and improved their mechanical properties. The gelatinization process of the moulded material was influenced by the predominant lineal structure of the carbohydrate content.  相似文献   

13.
Tight-fitting clothing pattern reflecting the accurate information of the 3D body shape has been one of the challenges for garment industry especially for those who have an abnormal body shape. The objective of the paper is to develop the process of making a final 2D pattern from 3D scanned surface with minimum errors that fit tightly to an asymmetrical female manikin and secondly, to verify the proposed pattern development process from the free drawn design line on the specific 3D body. On the continuum of the previous methodology which provided the precise flattening algorithm on the local 3D surface, total pattern making process was investigated step by step. Final 2D pattern was constructed using non-extensible fabric and the accuracy of the pattern was investigated by shell-shell deviation of original 3D nude and clothed image. Area of each pattern block and corresponding 3D surface block was compared, and the detailed view of the triangle arrangements for the final pattern examined, confirming the topology of the concave and convex surface reflected correctly in the pattern. As results, the accuracy of the tight-fit dress pattern was satisfactory even for the asymmetrical female manikin with prominent curvature.  相似文献   

14.
玉米芽期和苗期耐盐性鉴定方法的比较分析   总被引:3,自引:1,他引:2  
刘学  周璇  曾兴  张林  王振华  邸宏 《玉米科学》2015,23(1):115-121
以9份不同耐盐级别的玉米自交系为试材,在芽期和苗期分别采用4种不同盐浓度进行处理,5种评价方法进行玉米耐盐性鉴定,依据各种方法的鉴定结果与试材实际耐盐级别的符合程度,筛选出最佳的鉴定方法和评价指标。结果表明,芽期相对盐害率和盐害指数鉴定法的鉴定结果与已知自交系耐盐性级别的相关系数分别为0.27和0.45;苗期盆栽鉴定法的两种评价方法鉴定结果与供试材料耐盐性级别的相关系数分别为0.90和0.85,苗期水培鉴定法的相关系数为0.67。采用苗情、株高变化率和干重变化率为指标的苗期盆栽耐盐性鉴定方法最适宜大量玉米种质资源的耐盐性筛选。  相似文献   

15.
Many fungal biosynthetic pathways are silent in standard culture conditions, and activation of the silent pathways may enable access to new metabolites with antitumor activities. The aim of the present study was to develop a practical strategy for microbial chemists to access silent metabolites in fungi. We demonstrated this strategy using a marine-derived fungus Penicillium purpurogenum G59 and a modified diethyl sulphate mutagenesis procedure. Using this strategy, we discovered four new antitumor compounds named penicimutanolone (1), penicimutanin A (2), penicimutanin B (3), and penicimutatin (4). Structures of the new compounds were elucidated by spectroscopic methods, especially extensive 2D NMR analysis. Antitumor activities were assayed by the MTT method using human cancer cell lines. Bioassays and HPLC-photodiode array detector (PDAD)-UV and HPLC-electron spray ionization (ESI)-MS analyses were used to estimate the activated secondary metabolite production. Compounds 2 and 3 had novel structures, and 1 was a new compound belonging to a class of very rare natural products from which only four members are so far known. Compounds 1–3 inhibited several human cancer cell lines with IC50 values lower than 20 μM, and 4 inhibited the cell lines to some extent. These results demonstrated the effectiveness of this strategy to discover new compounds by activating silent fungal metabolic pathways. These discoveries provide rationale for the increased use of chemical mutagenesis strategies in silent fungal metabolite studies.  相似文献   

16.
Authors studied on the applicability of image analysis technique using a scanner with a CCD (charged coupled deviced) to the evaluation of evenness of nonwovens because it has distinctive features to considerably save time and labor in the analysis compared with other classical methods. As specimens for the experiment, two different types that are unpatterned and patterned ones were prepared. For the unpatterned specimen, webs were chermically bonded, while for the patterned specimen, webs being thermally calendered with engraved roller. Several webs having various areal densities were prepared and bonded. Coefficient of variation (CV%) was used as a parameter to evaluate the evenness. Scanning conditions could be suitably set up through comparing the total variance to the between-group variance and to the within-group variance, respectively, on the images scanned at the different conditions. The 2D convolution method with smoothing filter kernel was introduced to further filter the noises on the scanned images. After the filtering process, the increase of web areal densities gave an uniform decrease of the CV%. This showed that the scanned image analysis with proper filtering process could be successfully applicable to the evaluation of evenness in nonwovens.  相似文献   

17.
This study was conducted to develop near-infrared reflectance spectroscopy (NIRS) equations to predict the amino acid and nitrogen content of milled rice powder. The samples were scanned by NIRS and analyzed for amino acid composition and total nitrogen by HCl hydrolysis–HPLC methodology and Kjeldahl method, respectively. The NIRS equations of 15 different amino acids, except for cystine, methionine and histidine, showed high coefficients of determination (RSQ=84.8–97.5%) and low standard errors in calibration (SEC) with 3 g samples for NIRS scanning, while the calibration models of cystine and histidine could explain less variation (RSQ with 77.7 and 65.0%). Calibration for methionine was not suitable to estimate methionine because of its very low RSQ (10.2%). The equations for total amino acids and nitrogen also showed high RSQ and lower SEC, respectively. Furthermore, calibration equations developed with only about 500 mg samples showed similar accuracy and reliability to those with the full cup by using the same calibration set. The equations developed for relative contents of total amino acids did not show good, effective calibration and cross-validation. Only eight different amino acids can be predicted using the equations because their RSQs of calibration were higher than 50.6% (50.6–73.9%). The others cannot be estimated with confidence by their relative contents due to lower RSQ in calibration. Moreover, their relative contents can be calculated from their absolute contents estimated by NIRS calibration.  相似文献   

18.
The aim of this study was capability of Indian Remote Sensing (IRS) data of 1D to detecting erosion features which were created from run-off. In this study, ability of PAN digital data of IRS-1D satellite was evaluated for extraction of erosion features in Nour-roud catchment located in Mazandaran province, Iran, using GIS techniques. Research method has based on supervised digital classification, using MLC algorithm and also visual interpretation, using PMU analysis and then these were evaluated and compared. Results indicated that opposite of digital classification, with overall accuracy 40.02% and kappa coefficient 31.35%, due to low spectral resolution; visual interpretation and classification, due to high spatial resolution (5.8 m), prepared classifying erosion features from this data, so that these features corresponded with the lithology, slope and hydrograph lines using GIS, so closely that one can consider their boundaries overlapped. Also field control showed that this data is relatively fit for using this method in investigation of erosion features and specially, can be applied to identify large erosion features.  相似文献   

19.
利用两系法配制玉米不育杂交种。应具备条件是:(1)不育系抗病性强;(2)所采用的不育系应归属C群;(3)不一育系应持有较多的保持系。研究指出,按照不育系双保持特性,利用掺和法配制杂交种。本文还就利用不育化单交种组配三交种、制种产量高的原因和恢复系的利用做了讨论。  相似文献   

20.
建立方法简便、分辨率高的水稻品种遗传多态性和真实性鉴定的分子指纹技术对于指导水稻育种和规范种子市场都具有重要意义。农业部颁布的水稻品种鉴定技术规程行业新标准是基于35个不同遗传特点的代表性水稻品种建立的SSR分子标记技术规程。本研究根据该标准方法,对94份杂交水稻亲本材料的遗传多态性和特异性进行了比较分析,结果表明,供试品种间至少具有3对以上引物扩增的DNA片段差异,即利用该标准能很好地区分供试杂交水稻亲本的遗传差异。对新标准中48对推荐引物的比较与分析表明,46对引物扩增的DNA片段多态性较高,而RM176和RM551两对引物扩增带多态性较低,因此在其染色体的其他位点可进一步研究多态性更高的分子标记。与标准中35个水稻品种的指纹库进行比较,发现了16个新的等位变异,这些位点可作为标准指纹库的信息补充,丰富标准库中的遗传信息。对94个杂交水稻亲本的分子指纹比较分析,发现23个亲本材料具有特异性分子标记,这些特异分子标记可应用于杂交组合的真实性以及杂交种子纯度的分子鉴定。根据供试亲本的数字分子指纹,构建了87个不育系与7个父本杂交的虚拟组合数字分子指纹库以及虚拟组合的真实性和纯度快速鉴定的特异数字分子标记。  相似文献   

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