199 research outputs found
Discrete curvature approximations and segmentation of polyhedral surfaces
The segmentation of digitized data to divide a free form surface into patches is one of the key steps required to perform a reverse engineering process of an object. To this end, discrete curvature approximations are introduced as the basis of a segmentation process that lead to a decomposition of digitized data into areas that will help the construction of parametric surface patches. The approach proposed relies on the use of a polyhedral representation of the object built from the digitized data input. Then, it is shown how noise reduction, edge swapping techniques and adapted remeshing schemes can participate to different preparation phases to provide a geometry that highlights useful characteristics for the segmentation process. The segmentation process is performed with various approximations of discrete curvatures evaluated on the polyhedron produced during the preparation phases. The segmentation process proposed involves two phases: the identification of characteristic polygonal lines and the identification of polyhedral areas useful for a patch construction process. Discrete curvature criteria are adapted to each phase and the concept of invariant evaluation of curvatures is introduced to generate criteria that are constant over equivalent meshes. A description of the segmentation procedure is provided together with examples of results for free form object surfaces
Partial wave analysis at BES III harnessing the power of GPUs
Partial wave analysis is a core tool in hadron spectroscopy. With the high
statistics data available at facilities such as the Beijing Spectrometer III,
this procedure becomes computationally very expensive. We have successfully
implemented a framework for performing partial wave analysis on graphics
processors. We discuss the implementation, the parallel computing frameworks
employed and the performance achieved, with a focus on the recent transition to
the OpenCL framework.Comment: 6 pages, 2 figures, prepared for the proceedings of Computing in High
Energy Physics (CHEP) 201
E-Learning in Business
e-Learning is replacing face-to-face classroom instruction in a growing number of businesses, but what is the prospect for the continued proliferation of e-learning in business? On one hand, the quality of instruction, the cost effectiveness of new technology, a supportive e-learning educational culture, an expansion of the Internet, an increase in online courses, shorter business cycles, mergers, and increasing competition encourage business use of e-learning. On the other hand, employee reticence in using learning technologies, insufficient corporate investment, lack of business-relevant university courses, narrow bandwidth, and Internet access issues are constricting the business use of these technologies
Automatic programming of simulation models
The concepts of software engineering were used to improve the simulation modeling environment. Emphasis was placed on the application of an element of rapid prototyping, or automatic programming, to assist the modeler define the problem specification. Then, once the problem specification has been defined, an automatic code generator is used to write the simulation code. The following two domains were selected for evaluating the concepts of software engineering for discrete event simulation: manufacturing domain and a spacecraft countdown network sequence. The specific tasks were to: (1) define the software requirements for a graphical user interface to the Automatic Manufacturing Programming System (AMPS) system; (2) develop a graphical user interface for AMPS; and (3) compare the AMPS graphical interface with the AMPS interactive user interface
Status Report of the DPHEP Study Group: Towards a Global Effort for Sustainable Data Preservation in High Energy Physics
Data from high-energy physics (HEP) experiments are collected with
significant financial and human effort and are mostly unique. An
inter-experimental study group on HEP data preservation and long-term analysis
was convened as a panel of the International Committee for Future Accelerators
(ICFA). The group was formed by large collider-based experiments and
investigated the technical and organisational aspects of HEP data preservation.
An intermediate report was released in November 2009 addressing the general
issues of data preservation in HEP. This paper includes and extends the
intermediate report. It provides an analysis of the research case for data
preservation and a detailed description of the various projects at experiment,
laboratory and international levels. In addition, the paper provides a concrete
proposal for an international organisation in charge of the data management and
policies in high-energy physics
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