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用标准C语言在IBM-PC兼容微机上开发了基于PROSITE数据库检索蛋白质序列功能位点的PPS程序,PROSITE是Bairoch建立的蛋白质功能位点或结构模式的资料库,为蛋白质序列分析和结构功能研究提供了新工具。 相似文献
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测井曲线拐点在测井层序地层分析中的应用研究 总被引:4,自引:3,他引:1
在层序地层学研究中,层序界面的划分是基础和重要的环节,而利用测井资料分析可以进行层序界面划分和进行较长期基准面旋回识别。测井曲线的值是深度的函数,测井曲线的一阶导数表示了曲线变化的趋势和变化的快慢,在某一范围内,当一阶导数呈现符号转换时,相对应的深度点的测井值即为该范围内极大(极小)值;测井曲线的二阶导数则表示曲线的凹凸性,在某一范围内,当二阶导数呈现符号转换时,相对应的深度点代表了测井曲线的拐点,即反映曲线凹凸性变化的转折点,亦即地层的分界面。基于以上特点,提出利用测井曲线拐点进行层序界面划分的原理和方法,并结合岩心和录井资料,对白音查干凹陷达28井腾格尔组不同级次沉积旋回、地层垒积、旋回特征随沉积厚度变化特点和不同级次基准面旋回进行研究,最后得到该地层单井测井层序地层分析结果。 相似文献
4.
Wun Seng Chou 《Applicable Algebra in Engineering, Communication and Computing》1995,6(4-5):245-250
Over finite field GF(q) withq a power of an odd primep, we characterize inversive maximal period polynomials in terms of polynomials of orderq + 1, and then we study some properties of polynomials of orderq + 1.This paper was written while the author was visiting the Institute of Information Processing, Austrian Academy of Sciences, AustriaThe author would like to thank the Institute of Information Processing, Austrian Academy of Sciences, Austria, for its hospitality and for using its facilities 相似文献
5.
A new method for computing the node-pair reliability of network systems modeled by random graphs with nodes arranged in sequence is presented. It is based on a recursive algorithm using the “sliding window” technique, the window being composed of several consecutive nodes. In a single step, the connectivity probabilities for all nodes included in the window are found. Subsequently, the window is moved one node forward. This process is repeated until, in the last step, the window reaches the terminal node. The connectivity probabilities found at that point are used to compute the node-pair reliability of the network system considered. The algorithm is designed especially for graphs with small distances between adjacent nodes, where the distance between two nodes is defined as the absolute value of the difference between the nodes’ numbers. The maximal distance between any two adjacent nodes is denoted by Γ(G), where G symbolizes a random graph. If Γ(G)=2 then the method can be applied for directed as well as undirected graphs whose nodes and edges are subject to failure. This is important in view of the fact that many algorithms computing network reliability are designed for graphs with failure-prone edges and reliable nodes. If Γ(G)=3 then the method's applicability is limited to undirected graphs with reliable nodes. The main asset of the presented algorithms is their low numerical complexity—O(n), where n denotes the number of nodes. 相似文献
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Optimal and Suboptimal Quadriphase Sequences Derived from Maximal Length Sequences over Z
_{{\bf 4}}
P. Udaya M.U. Siddiqi 《Applicable Algebra in Engineering, Communication and Computing》1998,9(2):161-191
The paper presents families of quadriphase sequences derived from maximal length sequences over having good correlation properties. These are: (i) families of quadriphase sequences of period from maximal length sequences over ; each family consisting of sequences, (ii) families of quadriphase sequences of period from interleaved maximal length sequences over ; each family consisting of sequences. Such sequences are of interest in quadriphase modulated code division multiple access communication systems,
where it is desirable to have large sets of sequences that possess low value of , the maximum magnitude of the periodic crosscorrelation and out of phase auto-correlation values. The sequences over are viewed as trace functions of appropriately chosen unit elements of Galois extension rings of . Quadriphase sequences are then obtained from sequences, by a quadriphase mapping, , from to roots of unity, given by, ; where and . Periodic correlation properties (correlation values and their distribution) of the quadriphase sequences are obtained by
using an Abelian association scheme on the elements of the corresponding Galois extension ring of . The majority of the families of sequences derived are optimal with respect to the Welch lower bound on ; the rest being suboptimal with bounded by , where is the period\newpage of the sequences. However nearly half of the sequences in these families are balanced.
Received July 18, 1995; revised version November 29, 1996 相似文献
9.
维修拆卸序列规划是整个维修性设计的重要内容。为了能够以较高的效率求解出产品中零件的拆卸方案,依据产品的基本信息和零件之间的约束关系,建立拆卸Petri网可达图,将拆卸序列规划问题转化为对Petri网可达图最优路径的搜索和寻优问题。同时利用蚁群优化算法对组合优化具有高强适应性的特征,改进基本蚁群算法,对可达图模型进行路径寻优,得到最优或次优的拆卸序列。最后通过实例验证了该方法的有效性。 相似文献
10.
Fei Yan Josef Kittler David Windridge William Christmas Krystian Mikolajczyk Stephen Cox Qiang Huang 《Image and vision computing》2014
Fully automatic annotation of tennis game using broadcast video is a task with a great potential but with enormous challenges. In this paper we describe our approach to this task, which integrates computer vision, machine listening, and machine learning. At the low level processing, we improve upon our previously proposed state-of-the-art tennis ball tracking algorithm and employ audio signal processing techniques to detect key events and construct features for classifying the events. At high level analysis, we model event classification as a sequence labelling problem, and investigate four machine learning techniques using simulated event sequences. Finally, we evaluate our proposed approach on three real world tennis games, and discuss the interplay between audio, vision and learning. To the best of our knowledge, our system is the only one that can annotate tennis game at such a detailed level. 相似文献