Home About us Contact
|
Home About us Contact | ||
|
|
||
Acceptable Solution (acceptable + solution)
Selected Abstracts2D nearly orthogonal mesh generationINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN FLUIDS, Issue 7 2004Yaoxin Zhang Abstract The Ryskin and Leal (RL) system is the most widely used mesh generation system for the orthogonal mapping. However, when this system is used in domains with complex geometry, particularly in those with sharp corners and strong curvatures, serious distortion or overlapping of mesh lines may occur and an acceptable solution may not be possible. In the present study, two methods are proposed to generate nearly orthogonal meshes with the smoothness control. In the first method, the original RL system is modified by introducing smoothness control functions, which are formulated through the blending of the conformal mapping and the orthogonal mapping; while in the second method, the RL system is modified by introducing the contribution factors. A hybrid system of both methods is also developed. The proposed methods are illustrated by several test examples. Applications of these methods in a natural river channel are demonstrated. It is shown that the modified RL systems are capable of producing meshes with an adequate balance between the orthogonality and the smoothness for complex computational domains without mesh distortions and overlapping. Copyright © 2004 John Wiley & Sons, Ltd. [source] On blends R32/R134a and R32/R125: Thermodynamic and heat transfer aspectsINTERNATIONAL JOURNAL OF ENERGY RESEARCH, Issue 9 2001A. Stegou-SagiaArticle first published online: 4 JUN 200 Abstract In this paper the author develops an algorithm on the basis of heat and thermodynamics theory, to predict data for film condensation on horizontal integral,fin tubes for R32/R134a and R32/R125 mixtures in 25/75, 50/50 per cent compositions by mass correspondingly. Emphasis is focused on the presentation of thermophysical properties of the blends involved in the process considered, i.e. liquid density, viscosity, surface tension, thermal conductivity and latent heat of vaporization. The main point of this work is to define with computational techniques the blend with the most favourable composition, as an environmentally acceptable solution for R22 replacement in some shell-side condensers. Copyright © 2001 John Wiley & Sons, Ltd. [source] Testing of a measurement model for baccalaureate nursing students' self-evaluation of core competenciesJOURNAL OF ADVANCED NURSING, Issue 11 2009Li-Ling Hsu Abstract Title.,Testing of a measurement model for baccalaureate nursing students' self-evaluation of core competencies. Aim. This paper is a report of a study to test the psychometric properties of the Self-Evaluated Core Competencies Scale for baccalaureate nursing students. Background. Baccalaureate nursing students receive basic nursing education and continue to build competency in practice settings after graduation. Nursing students today face great challenges. Society demands analytic, critical, reflective and transformative attitudes from graduates. It also demands that institutions of higher education take the responsibility to encourage students, through academic work, to acquire knowledge and skills that meet the needs of the modern workplace, which favours highly skilled and qualified workers. Methods. A survey of 802 senior nursing students in their last semester at college or university was conducted in Taiwan in 2007 using the Self-Evaluated Core Competencies Scale. Half of the participants were randomly assigned either to principal components analysis with varimax rotation or confirmatory factor analysis. Results. Principal components analysis revealed two components of core competencies that were named as humanity/responsibility and cognitive/performance. The initial model of confirmatory factor analysis was then converged to an acceptable solution but did not show a good fit; however, the final model of confirmatory factor analysis was converged to an acceptable solution with acceptable fit. The final model has two components, namely humanity/responsibility and cognitive/performance. Both components have four indicators. In addition, six indicators have their correlated measurement errors. Conclusion. Self-Evaluated Core Competencies Scale could be used to assess the core competencies of undergraduate nursing students. In addition, it should be used as a teaching guide to increase students' competencies to ensure quality patient care in hospitals. [source] Optimal feeder bus routes on irregular street networksJOURNAL OF ADVANCED TRANSPORTATION, Issue 2 2000Steven Chien The methodology presented here seeks to optimize bus routes feeding a major intermodal transit transfer station while considering intersection delays and realistic street networks. A model is developed for finding the optimal bus route location and its operating headway in a heterogeneous service area. The criterion for optimality is the minimum total cost, including supplier and user costs. Irregular and discrete demand distributions, which realistically represent geographic variations in demand, are considered in the proposed model. The optimal headway is derived analytically for an irregularly shaped service area without demand elasticity, with non-uniformly distributed demand density, and with a many-to-one travel pattern. Computer programs are designed to analyze numerical examples, which show that the combinatory type routing problem can be globally optimized. The improved computational efficiency of the near-optimal algorithm is demonstrated through numerical comparisons to an optimal solution obtained by the exhaustive search (ES) algorithm. The CPU time spent by each algorithm is also compared to demonstrate that the near-optimal algorithm converges to an acceptable solution significantly faster than the ES algorithm. [source] | ||||||||||