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41.
Based on the requirements of applying information technology to reform the traditional fashion industry, the method of fashion merchandising management in some medium-sized enterprises is discussed. By analyzing the actual domestic fashion industry environment, ideal model that could quickly respond to the market's changes is proposed which includes naming brand, target-market position, circumstances analysis and popularity anticipation, brand concept and style setting, fashion design, fashion category component, and sale strategy.  相似文献   
42.
The effects of different treatments, such as dry heat,wet heat, solvent vapor and ultrasonic, on propertiesof the cyclic oligomers on the surface of polyester fiberare studied. The components of surface oligomers areanalyzed through Thin-Layer Chromatograph. Theresult shows that: all of the treatment, especially  相似文献   
43.
On the basis of analysis on both the typical characteristics of Chinese traditional clothing and trendy fashion on present market that is inspired from it, this paper illustrates several re-creation methods of Chinese traditional clothing. These suggestions would push this oriental traditional clothing to a new high in world fashion field and adopted by more and more common people.  相似文献   
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45.
A new knitted composite artificial tracheal stent made of polyglactin(PGLA) and polypropylene (PP) filaments for reinforcement and regeneration of human trachea has been developed by plated-knitting technique on a small-diameter circular knitting machine. Both tensile and compressive tests were carried out to determine the Young's modulus and the critical pressure corresponding to crushing of the stent. The experimental results confirmed that the new type of knitted composite artificial stent is mechanically feasible.  相似文献   
46.
DecisionwithGreyCorrelationandAHPZHAJingminandZHONGDonghua(Dept.ofHydraulicicEngin.,TianjinUniversity,Tianjin300072,China)Abs...  相似文献   
47.
 为了满足在高饱和城市交叉路口采用背景差法实现车辆检测的需求,设计了一种基于背景评估的背景提取与更新算法。算法针对交叉路口的车流特点,提出了一种基于检测结果反馈的背景评估机制,并融合中值滤波与帧间差分算法,将含噪声的初始背景不断纠错更新,向真实背景逼近,最终提取出一个可用的背景图。实验结果表明:对于一个信号周期内不能放完所有排队车辆的高饱和交叉路口,算法具有较快的收敛速度,且算法复杂度满足实际工程应用要求。  相似文献   
48.
In the carpet tufting machine,feed rollers are used to guide the yarns positively.After deducing the general Euler formula of yarn tension under positive guide of rollers,a conclusion is got that the tension of yarns at the output side of each roller tends to decrease one by one.Afterwards,a computing formula of wrap angle of yarn passing through the feed roller is deduced by application of triangle geometry method.By analyzing the effect of each parameter on the yarn tension,values of the space between rollers and the roller diameter are proposed for design reference,and relations between the yarn tension and the two key parameters,the friction coefficient of roller surface and the speed of rollers,are illustrated in detail.Consequently,a policy is drawn out to control the yarn tension.The results of this paper provide not only theory foundation for empirical settings of the operational parameters of tufting machine,but also theory support for further research on yarn tension-control methods.  相似文献   
49.
Carboxymethyl starch with lower degree of substitution was blended with acrylate copolymer for revealing the relation between mechanical properties and chemical structure of blending film.Effects of carboxymethylation of starch,acrylate constituent units of acrylate copolymers,and copolymer content of the film on the properties were investigated.The mechanical properties were evaluated in terms of tensile strength,breaking elongation,abrasion resistance,and flex-fatigue resistance.Film morphology was examined with X-ray diffraction (XRD),scanning electron microscopy (SEM),and atomic force microscope (AFM).It was found that the properties depended on the degree of substitution of carboxymethyl starch,chemical structure of acrylate units,and content of acrylate copolymer.Phase-separation of the two ingredients occurred within film matrix and the separation was decreased after starch carboxymethylation.Breaking elongation and flex-fatigue resistance of the film reached maximums when acrylate copolymer content was 50%.Excessively increasing the content of acrylate copolymer reduced the film properties.  相似文献   
50.
In multi-user multiple input multiple output(MU-MIMO) systems,the outdated channel state information at the transmitter caused by channel time variation has been shown to greatly reduce the achievable ergodic sum capacity.A simple yet effective solution to this problem is presented by designing a channel extrapolator relying on Karhunen-Loeve(KL) expansion of timevarying channels.In this scheme,channel estimation is done at the base station(BS) rather than at the user terminal(UT),which thereby dispenses the channel parameters feedback from the UT to the BS.Moreover,the inherent channel correlation and the parsimonious parameterization properties of the KL expansion are respectively exploited to reduce the channel mismatch error and the computational complexity.Simulations show that the presented scheme outperforms conventional schemes in terms of both channel estimation mean square error(MSE) and ergodic capacity.  相似文献   
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