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1.
用于单芯片系统的改进型WXGA LCoS成像器   总被引:1,自引:1,他引:0  
本文讨论用于单芯片时序混色的菲利浦DD-720硅基液晶(LCoS)片。这种芯片主要用于HDTV背投影机和多媒体系统。与菲利浦以前的单片LCoS设计相比,由于该芯片具有电接口接点较少、封装简单和温度传感器内置等许多特点,使其应用于投影系统时成本降低。  相似文献   
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The colour reaction of potato glycoalkaloids, containing solanidine as steroid, with strong acids and paraformaldehyde was examined to elucidate the kinetics and mutual relationship of the ‘Clarke’ and ‘Marquis’ reactions. It was found that the influence of time of addition of paraformaldehyde was the major factor in deciding the type of colour changes encountered. This factor and the specific absorption kinetics have important consequences for the use of these types of colour reactions as a quantitative assay. According to the structural similarity of the steroidal part of potato glycoalkaloids and cholesterol, colour reactions of both have been compared, indicating that both steroids react in strong acids in the presence of an oxidator, provided that the more lipophilic character of cholesterol is taken into account. Therefore a similar mechanism of a serial oxidation of carbonium ions as in the case of cholesterol, is suggested as the basis for these specific colour reactions of potato glycoalkaloids.  相似文献   
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5座斯芬克司住宅的每一栋各容纳了14间为了充分利用地段和阳光而组织起来的公寓。建筑的体量在背向水面的方向被斜切,从而使得从湖岸和公寓所能看到的湖景不被阻隔。当人在从楼里往上走时,公寓的数目逐层递减。结果产生了一种斯芬克司式的轮廓,面向太阳的屋顶退台置于这个神话中的怪兽的脊背上。每个建筑体量的雨篷设计是不同的,从而使其独特的头部产生一种韵律感——从连接新开拓地和现有大陆的stichtse桥上看去的一条激动人心的天际线。  相似文献   
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In 7 experiments the authors investigated the locus of word frequency effects in speech production. Exp 1 demonstrated a frequency effect in picture naming that was robust over repetitions. Exps 2, 3, and 7 excluded contributions from object identification and initiation of articulation. Exps 4 and 5 investigated whether the effect arises in accessing the syntactic word (lemma) by using a grammatical gender decision task. Although a frequency effect was found, it dissipated under repeated access to a word's gender. Exp 6 tested whether the robust frequency effect arises in accessing the phonological form (lexeme) by having Ss translate words that produced homophones. Low-frequent homophones behaved like high-frequent controls, inheriting the accessing speed of their high-frequent homophone twins. Because homophones share the lexeme, not the lemma, this suggests a lexeme-level origin of the robust effect. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Numeric and curve parameters for freeform surface feature models   总被引:1,自引:0,他引:1  
The success of feature modelling systems depends to a large extent on offering user-friendly ways for specifying and varying feature models. In this paper, several new facilities are introduced for this.Numeric and curve parameters are presented for specification and variation of freeform surface feature models. Several properties of the parameters can be defined, such as the direction of evaluation for a curve parameter. In addition to parameters present in features, other parameters can be added to a feature model, including intersection curves between features.To provide these facilities, a new three-level structure is introduced, which includes a partially evaluated model that can capture new generic model entities, including feature intersection curves. The work has been implemented in a prototype surface feature modelling system with functionality for feature class definition, feature model creation, and advanced feature model variation through the new types of parameters.  相似文献   
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In an era of globalized trade relations where food and pharmaceutical products cross borders effortlessly, consumers face counterfeit and deteriorated products at elevated rates. This paper presents multifunctional, biodegradable hydrogel microparticles that can provide information on the authenticity and the potential deterioration of the tagged food or pharmaceutical formulations. These microparticles integrate spatially patterned authenticity code with two sensors—the first one detects possible presence of pathogenic microbes through monitoring pH while the second one identifies products stored above optimal temperatures via optical monitoring of the microparticle degradation. Particles are synthesized from a biocompatible polymer and a photoinitiator, dextran modified with 2‐hydroxyethylmethacrylate and riboflavin, respectively, using a continuous, high throughput method stop‐flow lithography. The proposed synthesis approach also enables crosslinking with visible light bringing about additional flexibility to flow lithography. Model liquid and solid food and pharmaceutical products are successfully labeled with microparticles and the functionality of the sensors in aqueous solutions is demonstrated.  相似文献   
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A connected algebraic group in characteristic 00 is uniquely determined by its Lie algebra. In this paper algorithms are given for constructing an algebraic group in characteristic 00, given its Lie algebra. In particular, this leads to an algorithm for finding a maximal reductive subgroup and the unipotent radical of an algebraic group.  相似文献   
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