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981.
In this paper, we study the matrix multiplication operators on Banach function spaces and discuss their applications in semigroups
for solving the abstract Cauchy problem. 相似文献
982.
In this paper, we present a novel graph-theoretical approach for representing a wide variety of sequence analysis problems
within a single model. The model allows incorporation of the operations “insertion”, “deletion”, and “substitution”, and various
parameters such as relative distances and weights. Conceptually, we refer the problem as the minimum weight common mutated sequence (MWCMS) problem. The MWCMS model has many applications including multiple sequence alignment problem, the phylogenetic analysis, the DNA sequencing
problem, and sequence comparison problem, which encompass a core set of very difficult problems in computational biology.
Thus the model presented in this paper lays out a mathematical modeling framework that allows one to investigate theoretical
and computational issues, and to forge new advances for these distinct, but related problems.
Through the introduction of supernodes, and the multi-layer supergraph, we proved that MWCMS is -complete. Furthermore, it was shown that a conflict graph derived from the multi-layer supergraph has the property that a
solution to the associated node-packing problem of the conflict graph corresponds to a solution of the MWCMS problem. In this
case, we proved that when the number of input sequences is a constant, MWCMS is polynomial-time solvable. We also demonstrated
that some well-known combinatorial problems can be viewed as special cases of the MWCMS problem. In particular, we presented
theoretical results implied by the MWCMS theory for the minimum weight supersequence problem, the minimum weight superstring
problem, and the longest common subsequence problem.
Two integer programming formulations were presented and a simple yet elegant decomposition heuristic was introduced. The integer
programming instances have proven to be computationally intensive. Consequently, research involving simultaneous column and
row generation and parallel computing will be explored. The heuristic algorithm, introduced herein for multiple sequence alignment,
overcomes the order-dependent drawbacks of many of the existing algorithms, and is capable of returning good sequence alignments
within reasonable computational time. It is able to return the optimal alignment for multiple sequences of length less than
1500 base pairs within 30 minutes. Its algorithmic decomposition nature lends itself naturally for parallel distributed computing,
and we continue to explore its flexibility and scalability in a massive parallel environment. 相似文献
983.
Arup Baksi Bidyut Kumar Roy Rasajit Kumar Bera 《Mathematical and Computer Modelling》2006,44(11-12):1069-1079
The fundamental equations of the problems of generalized thermoelasticity with one relaxation parameter including heat sources in infinite rotating magneto-thermo-viscoelastic media have been derived in the form of a vector matrix differential equation in the Laplace transform domain for a one dimensional problem. These equations have been solved by the eigenvalue approach to determine deformations, stress, and temperature. The results have been compared to those available in the existing literature. The graphs have been drawn to show the effect of rotation in the medium. 相似文献
984.
In the present paper, we study the rate of convergence in simultaneous approximation for the Bézier variant of the Baskakov-Beta operators by using the decomposition technique of functions of bounded variation. 相似文献
985.
In this paper, we introduce fuzzy mathematical programming (FMP) for decision-making related to software creation by selecting
optimal commercial-off-the-shelf (COTS) products in a modular software system. Each module in such software systems have different
alternatives with variations in their properties, for example, quality, reliability, execution time, size and cost. Due to
these variations, component-based software developers generally deals with the problem of selecting appropriate COTS products.
The development of COTS-based systems largely depends on the success of the selection process. Various crisp optimization
models of COTS products selection have been proposed in literature. However, in real COTS products selection problem, it is
difficult to estimate precisely the values of various model parameters due to lack of sufficient data and also because of
measurement errors. Hence, instead of crisp optimization model, if we use flexible optimization model then we might obtain
results which are more preferred by the decision maker. In this study, we use multiple methodologies such as quality model,
analytical hierarchy process and FMP to develop fuzzy multiobjective optimization model of the COTS products selection. To
determine a preferred compromise solution for the multiobjective optimization problem, an interactive fuzzy approach is used. 相似文献
986.
Himadri Kumar Mukerjee 《Topology and its Applications》2006,153(18):3467-3495
Complete PL and topological classification and partial smooth classification of manifolds homotopy equivalent to a Wall's manifold (defined as a mapping torus of a Dold manifold), introduced by Wall in his 1960 Annals paper on cobordism, have been done by determining: (1) the normal invariants of Wall's manifolds, (2) the surgery obstruction of a normal invariant and (3) the action of the Wall surgery obstruction groups on the smooth, PL and homeomorphism classes of homotopy Wall's manifolds (to be made precise in the body of the paper). Consequently classification results of automorphisms (self homeomorphisms, and self PL-homeomorphisms) of Dold manifolds follow. 相似文献
987.
We first introduce a new notion called statistical convergence of order α and primarily show that it gives rise to a decreasing chain of closed linear subspaces of the space of all bounded real sequences with sup norm which never coincides with the class of convergent sequences and in fact their intersection properly contains the class of convergent sequences. We then show that the same method can be applied for double sequences also and introduce the notion of statistical convergence of order (α,β). 相似文献
988.
Hemant Kumar Nashine Zoran Kadelburg Stojan Radenovi? 《Applied mathematics and computation》2012,218(9):5422-5432
We establish coupled coincidence point results for mixed g-monotone mappings under general contractive conditions in partially ordered cone metric spaces over solid cones. We also present results on existence and uniqueness of coupled common fixed points. Our results generalize, extend and unify several well known comparable results in the literature. To illustrate our results and to distinguish them from the earlier ones, we equip the paper with examples. 相似文献
989.
990.
We prove that every H(i) subset H of a connected space X such that there is no proper connected subset of X containing H, contains at least two non-cut points of X. This is used to prove that a connected space X is a COTS with endpoints if and only if X has at most two non-cut points and has an H(i) subset H such that there is no proper connected subset of X containing H. Also we obtain some other characterizations of COTS with endpoints and some characterizations of the closed unit interval. 相似文献