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51.
Congyong Su Author Vitae Yueting Zhuang Author Vitae Li Huang Author Vitae Fei Wu Author Vitae 《Pattern recognition》2005,38(6):813-824
In this paper we propose a robust learning-based face hallucination algorithm, which predicts a high-resolution face image from an input low-resolution image. It can be utilized for many computer vision tasks, such as face recognition and face tracking. With the help of a database of other high-resolution face images, we use a steerable pyramid to extract multi-orientation and multi-scale information of local low-level facial features both from the input low-resolution face image and other high-resolution ones, and use a pyramid-like parent structure and local best match approach to estimate the best prior; then, this prior is incorporated into a Bayesian maximum a posterior (MAP) framework, and finally the high-resolution version is optimized by a steepest decent algorithm. The experimental results show that we can enhance a 24×32 face image into a 96×128 one while the visual effect is relatively good. 相似文献
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Cellular integrity in yeasts is ensured by a rigid cell wall whose synthesis is controlled by a MAP kinase signal transduction cascade. In Saccharomyces cerevisiae upstream regulatory components of this MAP kinase pathway involve a single protein kinase C, which is regulated in part by interaction with the small GTPase Rho1p. This small G protein is in turn rendered inactive (GDP-bound) or is activated (GTP-bound) by the influence of GTPase activating proteins (GAPs) and the GDP/GTP exchange factors (GEFs), respectively. We report here on the isolation of a gene from Kluyveromyces lactis, KlROM2, which encodes a member of the latter protein family. The nucleotide sequence contains an open reading frame of 1227 amino acids, with an overall identity of 57% to the Rom2 protein of S. cerevisiae. Four conserved sequence motifs could be identified: a RhoGEF domain, a DEP sequence, a CNH domain and a less conserved pleckstrin homology (PH) sequence. Klrom2 null mutants show a lethal phenotype, which indicates that the gene may encode the only functional GEF regulating the cellular integrity pathway in K. lactis. Conditional genomic expression of KlROM2 resulted in sensitivity towards caffeine and Calcofluor white as typical phenotypes of mutants defective in this pathway. Overexpression of KIROM2 from multicopy plasmids under the control of the ScGAL1 promoter severely impaired growth in both S. cerevisiae and in K. lactis. The fact that the lethal phenotype was not prevented in mpk1 deletion mutants indicates that growth inhibition is not simply caused by hyperactivation of the Pkc1p signal transduction pathway. 相似文献
54.
The requirement for higher quality drinking water necessitates the application of more efficient water treatment techniques. Nanofiltration is one promising option for enhanced water treatment, for example, in enhanced organic matter removal. The characteristics of different nanofiltration membranes vary remarkably, and the selection of a membrane has to be made according to the requirements of an application. In this study six nanofiltration membranes (NF70, NF255, NTR-7450, NTR-7410, Desal-5 and TFC-S) were evaluated in improving the quality of chemically pre-treated surface water in a pilot-scale process. The results indicate that the membrane with high organics removal and slightly reduced ion removal characteristics (NF255) performed best in terms of product water quality as well as membrane productivity and fouling. The most permeable membrane (NTR-7410) suffered intensive fouling and insufficient product water quality. An interesting finding was that the permeates of all the tested membranes possessed a significant potential for microbial growth, despite the low nutrient contents. 相似文献
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在文章中,首先介绍Turbo码的基本编译码结构和它的译码算法MAP。在此基础上,尝试对MAP算法的循环译码的后向递推的起点以及循环译码结构的最终判决条件根据实际应用情况进行改进。将译码的后向递推的起点定义为译码的前向递推的终点,并且将每一轮译码结果进行加权相加,得到最后系统输出。最后,根据MATLAB仿真的结果论证改进后的算法能减少系统的误码率。 相似文献
56.
G.C. Fletcher G. Summers V. Corrigan S. Cumarasamy J.P. Dufour 《Journal of food science》2002,67(6):2362-2374
ABSTRACT: King salmon ( Oncorhynchus tshawytscha ) packaged in air (AIR), nitrogen (N2), or 40:60 carbon dioxide:nitrogen (CO2N2) was stored (0 °C) for 18, 25, and 54 d, respectively. Air packs (AIR9) were also stored at 9 °C for 4 d. A quality index (QI) method was developed to monitor sensory quality of cooked salmon. First detection of spoilage was 1.5, 15, 15, and 21 d for AIR9, AIR, N2, and CO2N2 treatments respectively. Total aerobic and sulfide-producing bacteria, pH, drip loss, Eh , color, texture, ATP derivatives, trimethylamine, total volatile base nitrogen, thiobarbituric acid numbers, and peroxide values were determined. Only total aerobic counts and hypoxanthine were indicators of sensory deterioration across treatments and times. 相似文献
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基于指针推进机制的分层移动IPv6方案因未考虑移动锚点管理域的影响,导致较高的注册和报文分发开销.提出一种面向分层移动IPv6网络的动态指针推进机制(dynamic pointer forwarding scheme for HMIPv6 networks,简称DPF-HMIPv6),移动节点可根据所选移动锚点的管理域大小,动态调整指针推进机制.若所选移动锚点的管理域大于特定阈值,则移动节点通过在接入路由器间构建指针链来避免频繁地向移动锚点注册;若所选移动锚点的管理域小于阈值,则移动节点通过在移动锚点间构建指针链来避免频繁地向家乡代理注册.数值分析和仿真实验的结果表明,该方案能够有效解决现有方案存在的问题,显著降低分层移动IPv6网络的开销. 相似文献
60.
对不同气调包装(MAP)的香菇甲醛含量与理化关系进行研究。研究结果表明:贮藏期间,香菇甲醛含量与GGT和C-Slyase两酶比活呈显著正相关(相关系数r分别为0.777和0.700),而GGT和C-Slyase酶活与香菇的呼吸强度呈显著正相关(相关系数r分别为0.539和0.701)。MAP能抑制酶活,控制甲醛含量,减缓香菇蛋白质的降解和相对膜透性的增高。贮藏前12d,3组MAP香菇的甲醛平均含量比对照低13.00%(P<0.01)。其中,MAP(1)(7%CO2)香菇的平均含水率和蛋白质含量比对照高2.23%和7.81%,细胞膜透性平均比对照低27.24%,3种含硫风味化合物相对含量分别比对照低16.23%以上,品质保鲜效果最佳。 相似文献