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31.
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The problems of finding maximal and minimal equivalent representations for gapped and non-gapped motifs as well as finding motifs that characterize a fixed set of occurrence locations for a given string are studied. We apply two equivalence relations on representations. The first one is the well-known occurrence-equivalence of motifs. The second equivalence is introduced for patterns of occurrence locations, to characterize such patterns by motifs. For both equivalences, quadratic-time algorithms are given for finding a maximal representative of an equivalence class. Finding a minimal representative is shown to be NP-complete in both cases. For non-gapped motifs suffix-tree-based linear-time algorithms are given for finding maximal and minimal representatives. Maximal (minimal) gapped motifs are composed of blocks that are maximal (minimal) non-gapped motifs, maximal and minimal non-gapped motifs thus making up a small basis for all motifs. The implied bound on the number of gapped motifs that have a fixed number of non-gapped blocks is also given. 相似文献
33.
步态识别是一种新的生物特征识别技术,它旨在根据人们走路的姿势进行身份识别本文就远距离人体识别算法以及步态识别所涉及到的运动分割.特征提取,模式识别进行了研究,给出了实验图像。特别对基于模型的步态特征识别和基于人体行走的步态序列特征进行识别两种方法进行了比较和分析。 相似文献
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岩性油藏预测技术 总被引:12,自引:0,他引:12
提出岩性油藏勘探的预测配套技术:以层序地层学理论为指导,建立层序地层格架,研究层序内各体系域沉积体纵向堆砌方式、类型及宏观展布规律,预测有利沉积体;针对预测的具体目标,进行常规有井约束地震波阻抗反演,定性预测各体系域内砂组变化规律,为部署预探井提供依据;针对预探井所揭示的有效含油砂组,应用高分辨率波阻抗反演和人工神经网络技术,进行纵向分辨、横向追踪,定量预测各含油砂组的分布范围、物性参数和含油性,为部署评价井提供依据。在开鲁盆地陆西凹陷五十家子庙洼陷及马北斜坡带岩性油藏勘探的各个阶段,应用这套综合预测技术发现了一批岩性圈闭,预测结果为储量计算提供了可靠参数,能够在钻少量井的条件下直接上报探明储量,大大减少钻探投资。该方法也适用于地震资料品质较好的各类凹陷其它类型油气藏的勘探,已在辽河外围盆地的油气勘探中广泛应用。图5参6(王孝陵摘) 相似文献
35.
通过对程序ⅥB发动机台架试验新油和老化油的运动黏度、摩擦系数、钙元素浓度、总酸值和总碱值等理化性能分析,考察了程序ⅥB发动机台架试验老化对油品理化性能的影响。结果表明,在程序ⅥB发动机台架试验中油品运动黏度随老化时间的增加先下降后上升;油品的摩擦系数随老化时间的增加而增大,老化初期摩擦系数增大速度较快,老化后期摩擦系数增大速度减缓;老化造成油品钙元素浓度增大,老化初期油品钙元素浓度增大较快,后期油品钙元素浓度增大速度减缓;老化造成油品总酸值增大、总碱值下降。 相似文献
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Sunny Wang Author Vitae 《World Patent Information》2011,33(1):67-71
The biological pharmaceutical market is one of the fastest growing sectors in the health care business. Sales of biologic drugs reached $120 billion in 2008 [1] and the worldwide market of biologics continues to grow (IMS Health). As patents on first generation of biologic drugs, including epoetin, insulin granulocyte colony-stimulating factor (G-CSF) and interferon alpha, will soon expire, if they have not already, and patents on some of the second generation of biological drugs, such as antibody drugs, are going to be expire in the next few years, there exists a great opportunity in developing biosimilars, especially for large pharmaceutical companies which face great challenges in developing new blockbuster drugs. In the past few years, the United States, Canada, and Japan have debated or passed legislation on biosimilars with active involvement from top pharmaceutical and generic drug companies. The successful leader in this field will be the one that has the foresight and resources to position themselves well to gain in the future. So what are biosimilars? What are the technological differences between biosimilars and small molecule generic drugs? Finally, what are the considerations for biosimilars in terms of patent searching? An example on a biosimilar study is given here. 相似文献
39.
Antoine B. Rauzy 《Reliability Engineering & System Safety》2011,96(7):785-792
A large attention has been focused on the Dynamic Fault Trees in the past few years. By adding new gates to static (regular) Fault Trees, Dynamic Fault Trees aim to take into account dependencies among events. Merle et al. proposed recently an algebraic framework to give a formal interpretation to these gates.In this article, we extend Merle et al.'s work by adopting a slightly different perspective. We introduce Sequence Algebras that can be seen as Algebras of Basic Events, representing failures of non-repairable components. We show how to interpret Dynamic Fault Trees within this framework. Finally, we propose a new data structure to encode sets of sequences of Basic Events: Sequence Decision Diagrams. Sequence Decision Diagrams are very much inspired from Minato's Zero-Suppressed Binary Decision Diagrams. We show that all operations of Sequence Algebras can be performed on this data structure. 相似文献
40.
The authors propose a simple version of the dot-plot scheme to be used in the case when the distances between sequence elements may take more than two values. The method is applicable, in particular, to the case of the sequences of large-length windows when the sets of distance values are continuous. The proposed technique is simple to implement and the results can produce readable maps for further analysis. To illustrate its potentialities, the method has been applied to the comparison of genomic sequences. The asymmetry in the number of direct and reverse tracks for the Homo sapience genome has been discovered. 相似文献