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91.
Towards an ontology-based retrieval of UML Class Diagrams 总被引:1,自引:0,他引:1
Karina RoblesAnabel Fraga Jorge MoratoJuan Llorens 《Information and Software Technology》2012,54(1):72-86
Context
Software Reuse has always been an important area amongst software companies in order to increase their productivity and the quality of their products, but code reuse is not the only answer for this. Nowadays, reuse techniques proposals include software designs or even software specifications. Therefore, this research focuses on software design, specifically on UML Class Diagrams. A semantic technology has been applied to facilitate the retrieval process for an effective reuse.Objective
This research proposes an ontology-based retrieval technique by semantic similarity in order to support effective retrieval process for UML Class Diagrams. Since UML Class Diagrams are a de facto standard in the design stages of a Software Development Process, a good technique is needed to reuse them, i.e. reusing during the design stage instead of just the coding stages.Method
An application ontology modeled using UML specifications was designed to compare UML Class Diagram element types. To measure their similarity, a survey was conducted amongst UML experts. Query expansion was improved by a domain ontology supporting the retrieval phase. The calculus of minimal distances in ontologies was solved using a shortest path algorithm.Results
The case study shows the domain ontology importance in the UML Class Diagram retrieval process as well as the importance of an element type expansion method, such as an application ontology. A correlation between the query complexity and retrieved elements has been identified, by analyzing results. Finally, a positive Return of Investment (ROI) was estimated using Poulin’s Model.Conclusion
Because Software Reuse has not to be limited to the coding stage, approaches to reuse design stage must be developed, i.e. UML Class Diagrams reuse. This approach proposes a technique for UML Class Diagrams retrieval, which is one important step towards reuse. Semantic technology combined with information retrieval improves the retrieval results. 相似文献92.
A.J.M. Ferreira R.C. Batra C.M.C. Roque L.F. Qian R.M.N. Jorge 《Composite Structures》2006,75(1-4):593-600
We use the global collocation method, the first and the third-order shear deformation plate theories, the Mori–Tanaka technique to homogenize material properties, and approximate the trial solution with multiquadric radial basis functions to analyze free vibrations of functionally graded plates. Frequencies computed by the present method are found to agree well with those from the analytical solution of Vel and Batra, and the numerical solution of Qian et al. based on the meshless local Petrov–Galerkin formulation. 相似文献
93.
D. P. Recio R. M. Natal Jorge L. M. S. Dinis 《International journal for numerical methods in engineering》2006,68(13):1329-1357
The meshless methods, namely the element‐free Galerkin method (EFGM), when they first appeared claimed that volumetric locking and hourglass were avoided. This was not the case and both phenomena occur in the EFGM. In the context of the finite element method (FEM) these phenomena were widely studied. In this work, forms of avoiding the locking phenomenon will be presented; a formulation based on the enhanced strain method will be introduced in the EFGM and the B‐bar method will be implemented under the scope of the EFGM. Secondly, to render this method more robust, a stabilization technique will be implemented avoiding hourglass. Several examples are solved to probe the efficiency of these techniques. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
94.
Jongchul Song Walter R. Fagerlund Carl T. Haas Clyde B. Tatum Jorge A. Vanegas 《Canadian Metallurgical Quarterly》2005,131(6):723-733
Prefabrication, preassembly, modularization, and off-site fabrication, collectively termed as prework have become more viable with recent advances in design and information technologies. These construction methods offer a substantial opportunity to improve project performance when circumstances merit. Successful implementation of these methods on a particular project requires systematic analysis and early decision making based on specific factors of the project. This paper identifies those factors influencing decisions on the use of prework, and current industry practices for evaluating the applicability of prework on industrial projects. It then presents a decision framework to assist industry practitioners with evaluating the applicability of prework on their project, and describes a computerized tool to aid project teams in the decision-making process. The developed framework and tool are useful and effective in the decision-making process, and easy to use, as validated by practitioners in the industry. 相似文献
95.
R.C. Fadanelli P.L. Grande M. Behar J.F. Dias G. Schiwietz 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2005,230(1-4):96
In this work we have measured the contribution of the Coulomb explosion to the electronic stopping power of molecular hydrogen ions and channeling along the Si 1 0 0 direction. We have used a SIMOX target, consisting of crystalline Si 1 0 0 with a buried layer of SiO2. The measurements of the energy loss of H+, and have been carried out using the standard channeling Rutherford backscattering spectrometry. The energy loss has been measured around the Si 1 0 0 channel at a fixed energy per nucleon (150 keV/amu) as a function of the tilt and azimuthal angles. The present results show the effect of Coulomb explosion, which enlarges the protons traversal energy and consequently the channeling energy loss. This heating effect due to ions is about two times larger than molecules and amounts to about 5% of the total stopping power. 相似文献
96.
简述了计算运动学的发展过程,论述了计算运动学的基础理论,并利用两个实例展现了计算运动学在机构运动分析中的作用。最后以转向机构综合为例,对比传统综合方法和现代计算运动学方法的特点。结果表明:计算运动学方法在寻找所有解,精度和系统性等方面具有较大的优势。 相似文献
97.
Tuyet Le-Anh Jorge Villalobos Jacky Estublier 《Electronic Notes in Theoretical Computer Science》2003,82(5):164
Reusability is the holly grail of software engineers. But reusability requires powerful composition mechanisms since the pieces to compose have no reason to match perfectly. Unfortunately, the composition mechanisms available today, mostly method call and component assembly are rather primitive. This paper shows what is the current state of the art in software composition, showing that there is little composition flexibility at code level, even using workflow approaches.The approach presented here claims that composition requires reasoning at different levels of abstraction. Workflow support is first decoupled from real tools, using abstract tool modeling. Contracts have been included to increase the independence between process and tools. Then, we have introduced conceptual abstractions linked by contract to real tools. Finally, we show that it is possible to define composition at the abstract level.The resulting system shows very high adaptability capabilities. Experience shows, however, that to be practical, this approach requires adapted framework and specialized tools. This paper shows the experience gained in implementing many versions of such a framework. The current system is currently in industrial use. 相似文献
98.
Multicast multi-layered communications must implement efficient control algorithms to address undesirable network behaviors. This paper proposes two multi-metric algorithms for computing the rates of the video layers and improve the global video quality of a multicast session. In fact, we show that a single-metric approach may degrade some network parameters without obtaining any substantial improvements. Our first algorithm combines three metrics and a set of weights in such a way that one metric can be prioritized. This leads to an improved quality of multicast sessions, as we show through a number of experiments. In networks where the available resources are highly variable, however, the stability of the video quality is compromised if absolute values of the metrics are adopted. We then propose a second algorithm that uses the relative values of the metrics on a per-entry basis. Computation of the global quality of the multicast session is based on a differential matrix that stores the metrics for each receiver. This scheme takes into account the dynamics of the available resources and the heterogeneity of receivers. The great benefit of this approach is that the global video quality is always improved for every loop of the algorithm. 相似文献
99.
Colajanni M. Yu P.S. Dias D.M. 《Parallel and Distributed Systems, IEEE Transactions on》1998,9(6):585-600
A distributed multiserver Web site can provide the scalability necessary to keep up with growing client demand at popular sites. Load balancing of these distributed Web-server systems, consisting of multiple, homogeneous Web servers for document retrieval and a Domain Name Server (DNS) for address resolution, opens interesting new problems. In this paper, we investigate the effects of using a more active DNS which, as an atypical centralized scheduler, applies some scheduling strategy in routing the requests to the most suitable Web server. Unlike traditional parallel/distributed systems in which a centralized scheduler has full control of the system, the DNS controls only a very small fraction of the requests reaching the multiserver Web site. This peculiarity, especially in the presence of highly skewed load, makes it very difficult to achieve acceptable load balancing and avoid overloading some Web servers. This paper adapts traditional scheduling algorithms to the DNS, proposes new policies, and examines their impact under different scenarios. Extensive simulation results show the advantage of strategies that make scheduling decisions on the basis of the domain that originates the client requests and limited server state information (e.g., whether a server is overloaded or not). An initially unexpected result is that using detailed server information, especially based on history, does not seem useful in predicting the future load and can often lead to degraded performance 相似文献
100.
Gilles Celeux Author Vitae Author Vitae Jorge Marques Author Vitae 《Pattern recognition》2004,37(9):1841-1853
Many recent tracking algorithms rely on model learning methods. A promising approach consists of modeling the object motion with switching autoregressive models. This article is involved with parametric switching dynamical models governed by an hidden Markov Chain. The maximum likelihood estimation of the parameters of those models is described. The formulas of the EM algorithm are detailed. Moreover, the problem of choosing a good and parsimonious model with BIC criterion is considered. Emphasis is put on choosing a reasonable number of hidden states. Numerical experiments on both simulated and real data sets highlight the ability of this approach to describe properly object motions with sudden changes. The two applications on real data concern object and heart tracking. 相似文献