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排序方式: 共有367条查询结果,搜索用时 15 毫秒
91.
Chee-Fai Yung Chi-Ming Yang 《Automatic Control, IEEE Transactions on》1999,44(11):2058-2062
In this correspondence, the H∞ control problem is studied for finite-dimensional linear time-varying (FDLTV) systems. State-space formulas are derived for all FDLTV controllers solving the problem. These controllers are parameterized by the interconnection of the “central controller” with an exponentially stable, free system having H∞ norm strictly less than γ. Our approach is drawn from some changes of variables, a time-varying version of a strict bounded real lemma, and Youla parameterization; thus, the proofs given are simple and clear 相似文献
92.
Bo-Kai Ge Geng-Ming Hu Rex Chen Chi-Ming Chen 《International journal of molecular sciences》2022,23(22)
MSClustering is an efficient software package for visualizing and analyzing complex networks in Cytoscape. Based on the distance matrix of a network that it takes as input, MSClustering automatically displays the minimum span clustering (MSC) of the network at various characteristic levels. To produce a view of the overall network structure, the app then organizes the multi-level results into an MSC tree. Here, we demonstrate the package’s phylogenetic applications in studying the evolutionary relationships of complex systems, including 63 beta coronaviruses and 197 GPCRs. The validity of MSClustering for large systems has been verified by its clustering of 3481 enzymes. Through an experimental comparison, we show that MSClustering outperforms five different state-of-the-art methods in the efficiency and reliability of their clustering. 相似文献
93.
针对传统的单分类器不适用于周期时间序列的异常检测,提出了一种基于移相加权球面单簇聚类的单分类器PS-WS1M-OCC.通过在聚类过程中增加高效的循环移位操作,解决了时间序列记录之间相似度计算的问题.另一方面,基于时间序列记 录的权重分布,提出了新的阈值自适应确定方法,从而使单分类器对训练集包含的异常数据和参数设置不敏感.实验表明,本文提出的单分类器可以用于周 期时间序列的异常检测;与传统的单分类器相比,可以成功地从包含异常数据的训练集中进行无监督学习,对训练集包含的异常数据鲁棒,并且对参数不敏感. 相似文献
94.
基于启发式搜索分离向量的凸多面体碰撞检测 总被引:7,自引:0,他引:7
碰撞检测是计算机模拟物理过程的基础,在计算机图形学、CAD/CAM、虚拟现实和机器人等领域有着广泛的应用.该文给出了一个新的用于凸多面体碰撞检测的算法——HP-jump.HP-jump建立了一个有效的碰撞检测模型用于报告物体的碰撞,同时提供了一个快速的启发式的策略用于搜索两个凸多面体的分离向量.该算法是利用凸多面体的层次表示来搜索支撑顶点对,用平衡二叉树来记录球面凸多边形的顶点,同时还利用了时间、空间相关性,这些都加速了算法的执行.该文的最后给出了HP-jump与GJK,I-COLLIDE算法的比较. 相似文献
95.
This paper deals with the problem of joint determination of the optimal process mean and the production run for a process. It extends the Quality Selection problem to production systems in which the process mean (target) shifts to an out-of-control state due to an assignable cause. The problem has been validated using various examples. Moreover, results indicate that an inverse relationship exists for the length of production run and the difference expected profit between in-control state and out-of-control state. 相似文献
96.
以新鲜五味子为原料,对粉末醋制作工艺进行优化并对其产品质量进行分析。粉末醋制作工艺分为酒精发酵、醋酸发酵、果醋包埋、后熟以及喷雾干燥5个环节。通过单因素试验探讨酒精发酵工艺以及醋酸发酵工艺;通过响应面分析法优化果醋包埋条件和喷雾干燥条件。单因素试验结果表明,酒精发酵时果酱糖度调至13°Brix,醋酸发酵时醋酸菌接种量为10%时发酵效果较好;响应面分析结果表明,果醋包埋的最佳工艺条件为β-环糊精、卡拉胶以及藻胶钠的添加量分别为5.01%、0.63%、1.04%;喷雾干燥最佳工艺条件为进风量、进风温度以及进料速率分别为20.70 m^3/min,139.2℃以及499.6 mL/h。 相似文献
97.
The Taguchi method was applied to determine optimum conditions for submerged culture of Monascus spp. fermentation to produce a high yield of monacolin K (also known as lovastain, mevinolin or mevacor). The control factors included carbon, nitrogen, oil, and salt sources and pH values. In the growth phase the optimum culture conditions are 1% whole wheat flour, l% peptone, 0.01% olive oil and 0.01% potassium phosphate and a pH of 5.0 (P < 0.05). In the metabolic phase the optimal culture conditions are 1% whole wheat flour, 1% peptone, 0.01% soybean oil, 0.01% potassium phosphate and a pH of 3.0 (P < 0.001). Using optimal culture conditions in the growth and metabolic phases, the yield of monacolin K in the fermentation process was 151.06 ppm. 相似文献
98.
KYOUNG AH KANG HEE KYOUNG LIM SEUNG UK KIM YEONG WAN KIM WON TAEK KIM HA SOOK CHUNG MIN KYUNG CHOO DONG HYUN KIM HEE SUN KIM MI JA SHIM MYUNG-HEE CHUNG JIN WON HYUN 《Journal of Food Biochemistry》2005,29(1):27-40
We report the cytotoxicity of the ginseng saponin metabolite, Compound K (20‐O‐D‐glucopyranosyl‐20(S)‐protopanaxadiol, IH901) on various human leukemia cell lines. Compound K had the most effect on U937, a human monocytic leukemia cell line among the tested cell lines. Compound K‐treated U937 cells showed characteristics of apoptosis: an exposure of phosphatidylserine from the inner cell membrane to the outer cell membrane, the formation of apoptotic bodies and DNA fragmentation. Compound K induced apoptosis by up‐regulating Bax, disrupting the mitochondrial membrane potential, and by activating caspase 9 and caspase 3. Therefore, we suggest that Compound K inhibits U937 cell growth by inducing apoptosis through the up‐regulation of Bax and caspase activation. 相似文献
99.
KI-EUN LEE DUCK SOON AN EUN SOON LYU SUN KYUNG CHUNG DONG SUN LEE 《Journal of Food Processing and Preservation》2009,33(1):33-46
The aim of this study was to identify factors affecting the preservation of braised kidney beans, a traditional Korean side dish, to extend its shelf life. The effects of ingredient formulation, refrigerated storage and modified atmosphere packaging on storage stability and/or sensory quality were examined. Count of yeast/mold was selected as a primary quality index from the storage test at 10C. A formulation was found in cooked kidney beans, sugar, soy sauce and corn syrup to provide the retarded microbial growth and affordable sensory quality. The temperature dependence value (Q10 ) for the shelf life of the stretch-wrapped product was 2.0 for temperatures of 5 to 20C. Modified atmosphere packaging (60% CO2 /40% N2 or 100% CO2 ) extended the shelf life at 10C by 500% (to 36 days) compared to air packaging (6 days) based on criteria of yeast/mold growth. Equations for estimating microbial spoilage and shelf life were derived as function of temperature.
Microbial growth retardation by ingredient formulation change, chilled storage and high CO2 modified atmosphere packaging is useful to design the processing, packaging and distribution of the Korean side dish product. Quality change kinetics of yeast/mold growth established can be used for determining shelf life of the product under different storage temperature conditions. Through the scale-up procedure, the knowledge found in this study will be useful for the industrial processing and storage of the seasoned side dishes. 相似文献
PRACTICAL APPLICATIONS
Microbial growth retardation by ingredient formulation change, chilled storage and high CO
100.
De-Shin Liu Meng-Kae Shih Chi-Ming Chang 《Electronics Packaging Manufacturing, IEEE Transactions on》2009,32(1):49-58
The number of input and output pads on high-performance IC devices has increased in recent years, and hence wafer-level testing is conventionally performed using a probe card with a multilayer needle layout. This paper employs ANSYS commercial software and a Genetic Algorithm (GA) to optimize the design parameters of a multilayer needle probe card such that the scrub marks produced by the different needle layers are of approximately equal length. A dummy probe card containing both a conventional multilayer needle layout and the optimized needle layout is then fabricated and used in a series of single-contact probing tests. The results reveal that the scrub marks produced by the optimized needle layout are both shorter and of a more uniform length that those produced by the conventional needle design. For both needle layouts, a lower and more stable contact resistance is obtained as the overdrive distance is increased. Finally, a multicontact probing test is performed to evaluate the effect on the contact resistance of probe tip contamination following repeated surface contacts. The results show that the needles in the optimized layout are less heavily contaminated than those in the conventional layout, and hence the contact resistance is both lower and more stable. As a consequence, the probe card requires cleaning less frequently and hence its service life is improved. 相似文献