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101.
Ignacio Romero 《Computer Methods in Applied Mechanics and Engineering》2010,199(33-36):2235-2248
This article proposes a new type of discretizations for initial boundary value problems of thermodynamical systems. Based on a combination of finite elements in space and fractional step methods in time, we formulate algorithms that exactly preserve the symmetries and the laws of thermodynamics of the continuum problem. The algorithmic design is based on the GENERIC formalism of irreversible thermodynamics which naturally suggests the split of the evolution operator upon which our fractional step method is based. Although the emphasis of the article is on the generality of the results, as an illustration, a discretization of nonlinear, finite strain, thermoelasticity is presented. Numerical simulations are provided that verify the excellent performance of the new methods. 相似文献
102.
103.
Juan José Alfaro Saiz Author Vitae Raúl Rodríguez Rodriguez Author VitaeAuthor Vitae Maria Jose Verdecho Author Vitae 《Computers in Industry》2010,61(7):676-685
Recently, much attention has been given to performance management within collaborative environments resulting in a wide variety of performance measurement/management frameworks. However, practically all of these frameworks present a common gap regarding the information treatment needs that support these frameworks. This issue is even more important in the case of Small and Medium-sized Enterprises (SMEs) due to their special characteristics. For that purpose, this paper presents an approach called Global Performance Management (GPM) Framework composed of a methodology, an information architecture and a technological solution, focusing mainly on the information architecture. The methodology guides SMEs when defining, developing, deploying and operating the GPM framework. The information architecture consists of a set of elements that support the tasks of collection, treatment and analysis of the used information, which complement the methodology to build a real model for the GPM framework. Finally, the technological solution bridges the engineering and conceptual environment, with the real-world operational and executable environment, following the path defined by the methodology. The information architecture was applied to two European pilots, achieving satisfactory results, which are highlighted in the paper as well as the main barriers encountered and solutions provided. 相似文献
104.
Jose Gonzalez-Mora Fernando De la Torre Nicolas Guil Emilio L. Zapata 《Image and vision computing》2010
Over the last decade 3D face models have been extensively used in many applications such as face recognition, facial animation and facial expression analysis. 3D Morphable Models (MMs) have become a popular tool to build and fit 3D face models to images. Critical to the success of MMs is the ability to build a generic 3D face model. Major limitations in the MMs building process are: (1) collecting 3D data usually involves the use of expensive laser scans and complex capture setups, (2) the number of available 3D databases is limited, and typically there is a lack of expression variability and (3) finding correspondences and registering the 3D model is a labor intensive and error prone process. 相似文献
105.
New techniques for simulating high performance MPI applications on large storage networks 总被引:1,自引:0,他引:1
Alberto Núñez Javier Fernández Jose D. Garcia Félix Garcia Jesús Carretero 《The Journal of supercomputing》2010,51(1):40-57
In this work, we propose new techniques to analyze the behavior, the performance, and specially the scalability of High Performance
Computing (in short, HPC) applications on different computing architectures. Our final objective is to test applications using
a wide range of architectures (real or merely designed) and scaling it to any number of nodes or components. This paper presents
a new simulation framework, called SIMCAN, for HPC architectures. The main characteristic of the proposed simulation framework
is the ability to be configured for simulating a wide range of possible architectures that involve any number of components.
SIMCAN is developed to simulate complete HPC architectures, but putting special emphasis on the storage and network subsystems.
The SIMCAN framework can handle complete components (nodes, racks, switches, routers, etc.), but also key elements of the
storage and network subsystems (disks, caches, sockets, file systems, schedulers, etc.). We also propose several methods to
implement the behavior of HPC applications. Each method has its own advantages and drawbacks. In order to evaluate the possibilities
and the accuracy of the SIMCAN framework, we have tested it by executing a HPC application called BIPS3D on a hardware-based
computing cluster and on a modeled environment that represent the real cluster. We also checked the scalability of the application
using this kind of architecture by simulating the same application with an increased number of computing nodes. 相似文献
106.
Jose M. Álvarez Theo Gevers Antonio M. López 《International Journal of Computer Vision》2010,90(1):45-61
Color is a powerful visual cue in many computer vision applications such as image segmentation and object recognition. However,
most of the existing color models depend on the imaging conditions that negatively affect the performance of the task at hand.
Often, a reflection model (e.g., Lambertian or dichromatic reflectance) is used to derive color invariant models. However,
this approach may be too restricted to model real-world scenes in which different reflectance mechanisms can hold simultaneously. 相似文献
107.
Alfonso Rodríguez Ignacio García-Rodríguez de Guzmán Eduardo Fernández-Medina Mario Piattini 《Information and Software Technology》2010,52(9):945-971
ContextModel-Driven Development (MDD) is an alternative approach for information systems development. The basic underlying concept of this approach is the definition of abstract models that can be transformed to obtain models near implementation. One fairly widespread proposal in this sphere is that of Model Driven Architecture (MDA). Business process models are abstract models which additionally contain key information about the tasks that are being carried out to achieve the company’s goals, and two notations currently exist for modelling business processes: the Unified Modelling Language (UML), through activity diagrams, and the Business Process Modelling Notation (BPMN).ObjectiveOur research is particularly focused on security requirements, in such a way that security is modelled along with the other aspects that are included in a business process. To this end, in earlier works we have defined a metamodel called secure business process (SBP), which may assist in the process of developing software as a source of highly valuable requirements (including very abstract security requirements), which are transformed into models with a lower abstraction level, such as analysis class diagrams and use case diagrams through the approach presented in this paper.MethodWe have defined all the transformation rules necessary to obtain analysis class diagrams and use case diagrams from SBP, and refined them through the characteristic iterative process of the action-research method.ResultsWe have obtained a set of rules and a checklist that make it possible to automatically obtain a set of UML analysis classes and use cases, starting from SBP models. Our approach has additionally been applied in a real environment in the area of the payment of electrical energy consumption.ConclusionsThe application of our proposal shows that our semi-automatic process can be used to obtain a set of useful artifacts for software development processes. 相似文献
108.
Jose M. Chaves-González Miguel A. Vega-Rodríguez Juan A. Gómez-Pulido Juan M. Sánchez-Pérez 《Digital Signal Processing》2010,20(3):806-823
Skin colour detection is a technique very used in most of face detectors to find faces in images or videos. However, there is not a common opinion about which colour space is the best choice to do this task. Therefore, the motivation for our study is to discover which colour model is the best option to build an efficient face detector which can be embedded in a functional face recognition system. We have studied 10 of the most common and used colour spaces doing different comparisons among them, in order to know which one is the best option for human skin colour detection. In concrete, we have studied the models: RGB, CMY, YUV, YIQ, YPbPr, YCbCr, YCgCr, YDbDr, HSV—or HSI—and CIE-XYZ. To make the comparison among them, we have used 15 truth images where the skin colour of a face is clearly separated from the rest of the image (background, eyes, lips, hair, etc.). Thus we can compare at level pixel each colour model, doing a detailed study of each format. We present the final conclusions comparing different results, such as: right detections, false positives and false negatives for each colour space. According to the obtained results, the most appropriate colour spaces for skin colour detection are HSV model (the winner in our study), and the models YCgCr and YDbDr. 相似文献
109.
Francisco J. Rubio Francisco J. Valero Jose Luis Suñer Vicente Mata 《Asian journal of control》2010,12(4):468-479
This paper addresses the solution of smooth trajectory planning for industrial robots in environments with obstacles using a direct method, creating the trajectory gradually as the robot moves. The presented method deals with the uncertainties associated with the lack of knowledge of kinematic properties of intermediate via‐points since they are generated as the algorithm evolves looking for the solution. Several cost functions are also proposed, which use the time that has been calculated to guide the robot motion. The method has been applied successfully to a PUMA 560 robot and four operational parameters (execution time, computational time, distance travelled and number of configurations) have been computed to study the properties and influence of each cost function on the trajectory obtained. Copyright © 2010 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society 相似文献
110.
This article proposes an optimization–simulation model for planning the transport of supplies to large public infrastructure
works located in congested urban areas. The purpose is to minimize their impact on the environment and on private transportation
users on the local road network. To achieve this goal, the authors propose and solve an optimization problem for minimizing
the total system cost made up of operating costs for various alternatives for taking supplies to the worksite and the costs
supported by private vehicle users as a result of increased congestion due to the movement of heavy goods vehicles transporting
material to the worksite. The proposed optimization problem is a bi-level Math Program model. The upper level defines the
total cost of the system, which is minimized taking into account environmental constraints on atmospheric and noise pollution.
The lower level defines the optimization problem representing the private transportation user behavior, assuming they choose
the route that minimizes their total individual journey costs. Given the special characteristics of the problem, a heuristic
algorithm is proposed for finding optimum solutions. Both the model developed and the specific solution algorithm are applied
to the real case of building a new port at Laredo (Northern Spain). A series of interesting conclusions are obtained from
the corresponding sensitivity analysis. 相似文献