Component Integration Metrics and Their Evaluation

Software Engineering (SE) has been described as the discipline devoted to the design, development, and use of computer software, covering not only the technical aspects of building software systems, but also management issues develops highly complex software. The crisis in SE, due to the lack of well-defined formal processes, has led to poorly designed products with high maintenance costs and whose behavior becomes unpredictable. Component Based Software Engineering (CBSE) is currently a preferred approach to system design to overcome the crisis of SE, since it promotes software re-use, facilitates adaptability and faster system development. A component provides a function or a set of related functions, which forms a reusable program building block that can be combined with other components to form an application. A component with qualities such as, reusability, testability, modularity, complexity, proper to communicate and stability reduces maintenance costs. The components thus integrated, should be able to interoperate so that an operational application that results in reduced maintenance costs can be composed with minimal effort. Metrics are used to measure a component\u27s quality factor and there are no good metrics available to validate their effectiveness, when components are integrated. Currently, the success of projects based on the CBSE methodology relies on experts who assess software components; however, their evaluation process involves parameters that may not be measured in practice. Existing traditional metrics are inappropriate since CBSE is aimed at improving interoperability and re-usability. Size metrics based on lines of code are not applicable as component sizes may not be known a priori. Furthermore, complexities that arise due to varying nature of facets and interfaces are not addressed by traditional metrics. This thesis addresses the evaluation of a series of metrics based on complexity, criticality and dynamic behavior, in order that component integration performance can be assessed. Three suites of metrics defined by various authors have been considered for evaluation so that one could choose the best metrics to measure an integrated environment. A suite of metrics proposed by Narasimhan and Hendradjaya are classified based on the attributes of: complexity, criticality and dynamic aspects. These metrics use graph-based connectivity to represent a system of integrated components. While the complexity metrics consider the packing density of integrated components and the interaction density among the components, criticality metrics reveal the extent of binding within each component in the system. Dynamic metrics have also been collected during the execution of an application and aid the process involved in testing and maintenance. Metric related data sets have been from several benchmark programs using instrumentation programs and key inferences have been obtained; these inferences include a systematic evaluation of quality of the various metrics. Two new metrics have also been provided towards assessing the stability of the application: one metric, namely CRIT instability, calculates the instability of each component, while the second new metric, namely CRIT inheritance,counts the number of components whose children exceeds a threshold value. Both these metrics are useful to assess the stability of the application and, in addition, to determine the components in a given application that needs to be redesigned. Future work will focus on the development of a metric evaluation suite to assess the system\u27s stability as a whole, considering the role of each component in an application

Faithful transformation of quasi-isotropic to Weyl-Papapetrou coordinates: A prerequisite to compare metrics

We demonstrate how one should transform correctly quasi-isotropic coordinates to Weyl-Papapetrou coordinates in order to compare the metric around a rotating star that has been constructed numerically in the former coordinates with an axially symmetric stationary metric that is given through an analytical form in the latter coordinates. Since a stationary metric associated with an isolated object that is built numerically partly refers to a non-vacuum solution (interior of the star) the transformation of its coordinates to Weyl-Papapetrou coordinates, which are usually used to describe vacuum axisymmetric and stationary solutions of Einstein equations, is not straightforward in the non-vacuum region. If this point is \textit{not} taken into consideration, one may end up to erroneous conclusions about how well a specific analytical metric matches the metric around the star, due to fallacious coordinate transformations.Comment: 18 pages, 2 figure

Anholonomic Soliton-Dilaton and Black Hole Solutions in General Relativity

A new method of construction of integral varieties of Einstein equations in three dimensional (3D) and 4D gravity is presented whereby, under corresponding redefinition of physical values with respect to anholonomic frames of reference with associated nonlinear connections, the structure of gravity field equations is substantially simplified. It is shown that there are 4D solutions of Einstein equations which are constructed as nonlinear superpositions of soliton solutions of 2D (pseudo) Euclidean sine-Gordon equations (or of Lorentzian black holes in Jackiw-Teitelboim dilaton gravity). The Belinski-Zakharov-Meison solitons for vacuum gravitational field equations are generalized to various cases of two and three coordinate dependencies, local anisotropy and matter sources. The general framework of this study is based on investigation of anholonomic soliton-dilaton black hole structures in general relativity. We prove that there are possible static and dynamical black hole, black torus and disk/cylinder like solutions (of non-vacuum gravitational field equations) with horizons being parametrized by hypersurface equations of rotation ellipsoid, torus, cylinder and another type configurations. Solutions describing locally anisotropic variants of the Schwarzschild-- Kerr (black hole), Weyl (cylindrical symmetry) and Neugebauer--Meinel (disk) solutions with anisotropic variable masses, distributions of matter and interaction constants are shown to be contained in Einstein's gravity. It is demonstrated in which manner locally anisotropic multi-soliton-- dilaton-black hole type solutions can be generated.Comment: revtex, twocolumns, 24 pages, version 3 with minor correction

Information technology and performance management for build-to-order supply chains

En las siguientes líneas se plantea un artículo de reflexión que tiene en cuenta parte del marco teórico que sustenta la investigación titulada “Prácticas pedagógicas que promueven la competencia argumentativa escrita (CAE) en niños campesinos de los grados 4° y 5° del Centro Educativo Municipal La Caldera, Sede Principal de Pasto”, desarrollada en el año 2012. En él se contemplan los aportes de las ciencias del lenguaje y la comunicación, la teoría de la argumentación, la didáctica de la lengua escrita y los géneros discursivos, que dan cuenta de la necesidad de desarrollar la capacidad crítica en los estudiantes a través de la argumentación, lo cual implica transformar las prácticas pedagógicas para que se alejen de la transmisión de conocimientos y den paso a la comunicación, para que la palabra escrita sea apropiada de manera significativa

A MOSAIC of methods: Improving ortholog detection through integration of algorithmic diversity

Ortholog detection (OD) is a critical step for comparative genomic analysis of protein-coding sequences. In this paper, we begin with a comprehensive comparison of four popular, methodologically diverse OD methods: MultiParanoid, Blat, Multiz, and OMA. In head-to-head comparisons, these methods are shown to significantly outperform one another 12-30% of the time. This high complementarity motivates the presentation of the first tool for integrating methodologically diverse OD methods. We term this program MOSAIC, or Multiple Orthologous Sequence Analysis and Integration by Cluster optimization. Relative to component and competing methods, we demonstrate that MOSAIC more than quintuples the number of alignments for which all species are present, while simultaneously maintaining or improving functional-, phylogenetic-, and sequence identity-based measures of ortholog quality. Further, we demonstrate that this improvement in alignment quality yields 40-280% more confidently aligned sites. Combined, these factors translate to higher estimated levels of overall conservation, while at the same time allowing for the detection of up to 180% more positively selected sites. MOSAIC is available as python package. MOSAIC alignments, source code, and full documentation are available at http://pythonhosted.org/bio-MOSAIC

Ricci Collineations of the Bianchi Types I and III, and Kantowski-Sachs Spacetimes

Ricci collineations of the Bianchi types I and III, and Kantowski-Sachs space- times are classified according to their Ricci collineation vector (RCV) field of the form (i)-(iv) one component of $\xi^a (x^b)$ is nonzero, (v)-(x) two components of $\xi^a (x^b)$ are nonzero, and (xi)-(xiv) three components of $\xi^a (x^b)$ are nonzero. Their relation with isometries of the space-times is established. In case (v), when $det(R_{ab}) = 0$, some metrics are found under the time transformation, in which some of these metrics are known, and the other ones new. Finally, the family of contracted Ricci collineations (CRC) are presented.Comment: 21 Pages, LaTeX, no figures, accepted for publication in the International Journal of Modern Physics