5 resultados para PM3 semi-empirical method
em Universidad de Alicante
Resumo:
La rápida propagación del método empírico para combatir la viruela dado a conocer por Edward Jenner conllevó algunas dificultades. A la necesidad de obtener la máxima aceptación posible entre la población, se añadió la de ejecutar con rigor la técnica así como la de producir, transportar y conservar el fluido vacunal con garantías de calidad. Abastecerse de vacuna era una preocupación solventada en parte gracias a los envíos realizados desde instituciones radicadas en Londres o París. Tras su recepción se iniciaban cadenas de vacunaciones mediante la técnica del brazo a brazo. El temor a la extinción del fluido vacunal, no obstante, despertó el interés por la producción autóctona. Era necesario encontrar vacas afectadas por viruela vacuna o en su defecto aprender a conservar la materia vacunal en las propias vacas u otros animales. Varias iniciativas exploraron esta posibilidad. El fondo documental de la Biblioteca Nacional de España conserva un texto que refleja 2 de estos ensayos realizados en la Real Escuela Veterinaria de Madrid a cargo del médico Joaquín de Villalba y el albéitar Antonio Roura en 1802 y 1803. La tentativa no obtuvo el éxito deseado.
Resumo:
Several works deal with 3D data in SLAM problem. Data come from a 3D laser sweeping unit or a stereo camera, both providing a huge amount of data. In this paper, we detail an efficient method to extract planar patches from 3D raw data. Then, we use these patches in an ICP-like method in order to address the SLAM problem. Using ICP with planes is not a trivial task. It needs some adaptation from the original ICP. Some promising results are shown for outdoor environment.
Empirical study on the maintainability of Web applications: Model-driven Engineering vs Code-centric
Resumo:
Model-driven Engineering (MDE) approaches are often acknowledged to improve the maintainability of the resulting applications. However, there is a scarcity of empirical evidence that backs their claimed benefits and limitations with respect to code-centric approaches. The purpose of this paper is to compare the performance and satisfaction of junior software maintainers while executing maintainability tasks on Web applications with two different development approaches, one being OOH4RIA, a model-driven approach, and the other being a code-centric approach based on Visual Studio .NET and the Agile Unified Process. We have conducted a quasi-experiment with 27 graduated students from the University of Alicante. They were randomly divided into two groups, and each group was assigned to a different Web application on which they performed a set of maintainability tasks. The results show that maintaining Web applications with OOH4RIA clearly improves the performance of subjects. It also tips the satisfaction balance in favor of OOH4RIA, although not significantly. Model-driven development methods seem to improve both the developers’ objective performance and subjective opinions on ease of use of the method. This notwithstanding, further experimentation is needed to be able to generalize the results to different populations, methods, languages and tools, different domains and different application sizes.
Resumo:
Rock mass characterization requires a deep geometric understanding of the discontinuity sets affecting rock exposures. Recent advances in Light Detection and Ranging (LiDAR) instrumentation currently allow quick and accurate 3D data acquisition, yielding on the development of new methodologies for the automatic characterization of rock mass discontinuities. This paper presents a methodology for the identification and analysis of flat surfaces outcropping in a rocky slope using the 3D data obtained with LiDAR. This method identifies and defines the algebraic equations of the different planes of the rock slope surface by applying an analysis based on a neighbouring points coplanarity test, finding principal orientations by Kernel Density Estimation and identifying clusters by the Density-Based Scan Algorithm with Noise. Different sources of information —synthetic and 3D scanned data— were employed, performing a complete sensitivity analysis of the parameters in order to identify the optimal value of the variables of the proposed method. In addition, raw source files and obtained results are freely provided in order to allow to a more straightforward method comparison aiming to a more reproducible research.
Resumo:
The Remez penalty and smoothing algorithm (RPSALG) is a unified framework for penalty and smoothing methods for solving min-max convex semi-infinite programing problems, whose convergence was analyzed in a previous paper of three of the authors. In this paper we consider a partial implementation of RPSALG for solving ordinary convex semi-infinite programming problems. Each iteration of RPSALG involves two types of auxiliary optimization problems: the first one consists of obtaining an approximate solution of some discretized convex problem, while the second one requires to solve a non-convex optimization problem involving the parametric constraints as objective function with the parameter as variable. In this paper we tackle the latter problem with a variant of the cutting angle method called ECAM, a global optimization procedure for solving Lipschitz programming problems. We implement different variants of RPSALG which are compared with the unique publicly available SIP solver, NSIPS, on a battery of test problems.