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排序方式: 共有208条查询结果,搜索用时 125 毫秒
61.
在分析了Developer/2000源程序的基础上,给出基于其上的软件开发管理据结构、分析算法和功能实现途径,可以大大减少整理文档的工作量,提高软件的开发质量。 相似文献
62.
通过对多种面向对象开发工具开发软件进行文件组织分析,提出一个文件组织的层次模型.通过对具体VB语言的分析,获取VB语言的项目组织规则,并编程实现提取VB项目中的对象,包括属性和代码,以及对象之间的关系. 相似文献
63.
基于软计算协作技术的智能评审管理系统 总被引:1,自引:0,他引:1
基于模糊系统、神经网络、遗传算法和粗糙集等软计算的协作技术,建立了科研项目的立项评审智能管理系统。运用软件工程原理与方法,对该系统及其在科研项目立项评审的应用软件进行计划、开发和维护。实际应用表明了该系统的可行性和有效性,并可推广于其他智能管理系统。 相似文献
64.
The kinetic control of exothermic reactions plays an important role in chemical safety technology. Predictions of thermal explosions by runaway, e.g. redox reactions, poly reactions, and decompositions, are required in case of simple as well as of complex reactions. Activation parameters of chemical reactions are often stressed by systematic errors which are caused by failures in accuracy of measurement and calibration. The influence of systematic errors for some selected reactions has been investigated by the software package TA-kin. The coupling between continuous data evaluation software and the precision calorimeter ACTRON 5.0, including a safety scenario equipment, was established to test the validity of calculated runaway predictions under practical conditions. Measured data are applied for kinetic evaluations by nonlinear optimization methods in real time. In this way, the experimental investigations of reaction systems become possible beyond the point of no return without any danger for the laboratory. 相似文献
65.
Jackson AT Slade SE Thalassinos K Scrivens JH 《Analytical and bioanalytical chemistry》2008,392(4):643-650
The end-group functionalisation of a series of poly(propylene glycol)s has been characterised by means of electrospray ionisation–tandem
mass spectrometry (ESI-MS/MS). A series of peaks with mass-to-charge ratios that are close to that of the precursor ion were
used to generate information on the end-group functionalities of the poly(propylene glycol)s. Fragment ions resulting from
losses of both of the end groups were noted from some of the samples. An example is presented of how software can be used
to significantly reduce the length of time involved in data interpretation (which is typically the most time-consuming part
of the analysis).
Figure Screenshot from Polymerator software of annotated ESI-MS/MS spectrum from the lithiated heptamer of poly(propylene glycol)
di-acrylate 相似文献
66.
The likelihood approach is common in linkage analysis of large extended pedigrees. Various peeling procedures, based on the conditional independence of separate parts of a pedigree, are typically used for likelihood calculations. A peeling order may significantly affect the complexity of such calculations, particularly for pedigrees with loops or when many pedigrees members have unknown genotypes. Several algorithms have been proposed to address this problem for pedigrees with loops. However, the problem has not been solved for pedigrees without loops until now. In this paper, we suggest a new graph theoretic algorithm for optimal selection of peeling order in zero-loop pedigrees with incomplete genotypic information. It is especially useful when multiple likelihood calculation is needed, for example, when genetic parameters are estimated or linkage with multiple marker loci is tested. The algorithm can be easily introduced into the existing software packages for linkage analysis based on the Elston-Stewart algorithm for likelihood calculation. The algorithm was implemented in a software package PedPeel, which is freely available at http://mga.bionet.nsc.ru/nlru/. 相似文献
67.
Motivated by applications in software programming, we consider the problem of covering a graph by a feasible labeling. Given an undirected graph G=(V,E), two positive integers k and t, and an alphabet Σ, a feasible labeling is defined as an assignment of a set Lv⊆Σ to each vertex v∈V, such that (i) |Lv|≤k for all v∈V and (ii) each label α∈Σ is used no more than t times. An edge e={i,j} is said to be covered by a feasible labeling if Li∩Lj≠0?. G is said to be covered if there exists a feasible labeling that covers each edge e∈E.In general, we show that the problem of deciding whether or not a tree can be covered is strongly NP-complete. For k=2, t=3, we characterize the trees that can be covered and provide a linear time algorithm for solving the decision problem. For fixed t, we present a strongly polynomial algorithm that solves the decision problem; if a tree can be covered, then a corresponding feasible labeling can be obtained in time polynomial in k and the size of the tree. For general graphs, we give a strongly polynomial algorithm to resolve the covering problem for k=2, t=3. 相似文献
68.
This paper presents a general-purpose software framework dedicated to the design and the implementation of evolutionary multiobjective optimization techniques: ParadisEO-MOEO. A concise overview of evolutionary algorithms for multiobjective optimization is given. A substantial number of methods has been proposed so far, and an attempt of conceptually unifying existing approaches is presented here. Based on a fine-grained decomposition and following the main issues of fitness assignment, diversity preservation and elitism, a conceptual model is proposed and is validated by regarding a number of state-of-the-art algorithms as simple variants of the same structure. This model is then incorporated into the ParadisEO-MOEO software framework. This framework has proven its validity and high flexibility by enabling the resolution of many academic, real-world and hard multiobjective optimization problems. 相似文献
69.
In this paper, we consider an inventory system whose products share a common hardware platform but are differentiated by two types of software. Choice of different software results in different installation cost and different selling price of the whole product. Product with different software also faces different customer demand. We investigate the optimal proportion of an order to be installed with software 1 or 2, that maximizes expected profit in the single and multiple period scenarios, respectively. The optimal policy is analytically obtained and proved to be an order-up-to policy in each scenario. Our investigation reveals that whether to replenish, and how much to replenish each product depend not only on its own initial inventory level, and system parameters, but also the initial inventory level of the other product. We perform numerical experiments using the optimal policies we have derived in the paper. 相似文献
70.
Jorge Júlvez Cristian Mahulea Carlos-Renato Vázquez 《Nonlinear Analysis: Hybrid Systems》2012,6(2):806-817
This paper presents a MATLAB embedded package for hybrid Petri nets called SimHPN. It offers a collection of tools devoted to simulation, analysis and synthesis of dynamical systems modeled by hybrid Petri nets. The package supports several server semantics for the firing of both, discrete and continuous, types of transitions. Besides providing different simulation options, SimHPN offers the possibility of computing steady state throughput bounds for continuous nets. For such a class of nets, optimal control and observability algorithms are also implemented. The package is fully integrated in MATLAB which allows the creation of powerful algebraic, statistical and graphical instruments that exploit the routines available in MATLAB. 相似文献