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11.
理论上研究了吸收层材料的光学常数,该常数满足从紫外线到近红外波长范围的四层结构的光子-热转换的高效率。通过使用有效介质近似(EMA)模型,复合材料(金属陶瓷)的光学性能与模拟材料的光学性能非常吻合。此外,提出了使用Ti-MgF2金属陶瓷作为吸收层的具有高光子-热转换效率的四层膜结构,其在300~1 600 nm的波长范围内具有约95.1%的高吸收率。研究结果为实现高效率的光热转换器件提供了新途径,显示了优良的应用前景。  相似文献   
12.
This paper describes the design and implementation of a 3 KHz band HF data broadcast communication system, using a quantized frequency modulation, adaptive lattice equalizer together with forward error correcting code (FEC) to obtain a high link reliability and low error rate. A frequency diversity approach is also used in the selection of the timely best carrier frequency, and a microcomputer is implemented into the system for automatic best carrier acquisition, data transmission and clock synchronization, with minimum operator's attention. Extensive field experiments were conducted and experimental results indicate that the system can achieve, for daytime operation, a link reliability of 87–98%, with a probability of error between 10?4 to 10?5, depending upon data rate (50, 75bps) and FECs used. For night time operation, the link reliability reduces to from 65–93% with a probability of error down in the order of 10?3.  相似文献   
13.
AFFS技术在大尺寸LCD-TV的进展(英文)   总被引:2,自引:0,他引:2  
最近我们发展了AFFS技术,做出了32″LED背光源的LCD-TV,色域达到了105%,对比度1200:1,在140°所有视角的对比度达到了100以上,我们采用双轴补偿膜大大提高了颜色漂移的特性。这些光学特性结果的取得是与工艺制作、光学材料的优化、新AFFS像素的设计分不开的。  相似文献   
14.
采用传统的移动设备设计规则,基于PenTile RGBWTM算法开发了a-Si TFT移动液晶显示屏。将AFFS模式和PenTile RGBWTM算法相结合,制作的TFT液晶屏获得了超过200 cd/ m2的高亮度,500∶1的高对比度,以及达到VGA标准,可以清晰显示互联网网页的高分辨率。  相似文献   
15.
A simple and accurate model of a permanent magnet synchronous motor (PMSM) with a light load is presented in this paper. The light-load condition is always needed in integrated circuit manufacturing machines in order to achieve a fast, accurate and minimum overshoot response. The model proposed here can help a designer to specify the controller's specifications and also to verify the hardware of motor drives. The differential equations of the PMSM are handled by the macromodels in PSPICETM. Moreover, it is revealed that the PMSM system is operating in a 4-state mode rather than a 2-state mode. Experimental results are provided to verify the simulation results of this model. The heavy load condition is also simulated.  相似文献   
16.
After the remarkable increase of Internet users and broadband Internet subscribers at the end of the 20th century, the size of Korean Internet and e-commerce market steadily increased but the growth rate has been either stagnant or decreased. Trends of Korean Internet and e-commerce market are summarized in this paper the trends on Internet usage are introduced. Trends of online games, blogs and wireless Internet are introduced. The trends of Korean Internet market may have implications for China and Japan.  相似文献   
17.
针对GPU并行计算特征,对Viterbi解码自身做了并行处理探索,并提出使用Zero-Termination卷积码来实现基于GPU的Viterbi解码分块并行处理.设计的实现结果表明:Zero-Termination卷积码的简单而适用于GPU分块并行;误码率降低,特别是在信噪比低的情况下,Zero-Termination卷积码误码率比不损失码率的卷积码要低.同时,还实现了基于GPU的7,9,15三种不同约束长度的Viterbi解码,获得了良好的误码性能曲线及高吞吐率表现.  相似文献   
18.
Polyphenoloxidase (PPO) was isolated from two varieties of grapes grown in the northeastern United States and its characteristics were studied. The temperature and pH optima for both enzymes were 25°C and 5.5, respectively. The thermal inactivation of PPO followed first-order kinetics; with the Niagara enzyme being more heat stable than Ravat PPO. The substrate specificity of the grape PPO clearly showed high affinity toward the o-diphenolic compounds, with a high affinity toward caffeic acid. Inhibition studies indicated that L-cysteine and sodium diethyldithiocarbamate were the most potent.  相似文献   
19.
Meat emulsions were examined by light microscopy to determine the relationships between structure and emulsion stability. Beef-meat based emulsions were prepared either by varying chopping temperature or by adding soy plastic fats of different hardness. Formation of fat channels was observed in uncooked emulsions prepared either at a chopping temperature of 26°C or with soft plastic fat of 0.25cm?1 hardness index. Such fat channel formations caused discontinuity of protein matrix, leading to fat separation during cooking and weakening of textural strength of products. Changes in fat globule size and distribution as affected by melting properties or hardness of fats were clearly reflected by changes in emulsion stability. Results suggest that emulsion stability is determined largely by the physical properties of protein matrix and fat incorporated. Stable emulsions were obtained with fats of appropriate melting properties and hardness and relatively cohesive protein matrix under given comminution conditions which allowed uniform fat distribution.  相似文献   
20.
Centrifugal force was employed in order to induce a spatial gradient of fibre distribution in the epoxy/carbon fibre system. The gradient structure of the epoxy/carbon fibre composite can be controlled by varying the rotation time and the material parameters, such as fibre length, fibre content and matrix viscosity. The spatial gradient distribution of carbon fibres in an epoxy matrix was achieved by the combined mechanism of packing and settling. The mechanical properties of the functionally gradient epoxy/carbon fibre composite were also investigated. At the same content of carbon fibre, the flexural strength of the functionally gradient composite was higher than that of conventional isotropic composite. This revised version was published online in November 2006 with corrections to the Cover Date.  相似文献   
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