| 1. |
|
|
| 2. |
- Sarin, H., et al.
(författare)
-
A comprehensive metric for comparing time histories in validation of simulation models with emphasis on vehicle safety applications
- 2009
-
Ingår i: Proceedings of the ASME International Design Engineering Technical Conferences and Computers and Information in Engineering Conference - 2008. - New York : American Society of Mechanical Engineers. - 9780791843253 ; , s. 1275-1286
-
Konferensbidrag (refereegranskat)abstract
- Computer modeling and simulation are the cornerstones of product design and development in the automotive industry. Computer-aided engineering tools have improved to the extent that virtual testing may lead to significant reduction in prototype building and testing of vehicle designs. In order to make this a reality, we need to assess our confidence in the predictive capabilities of simulation models. As a first step in this direction, this paper deals with developing a metric to compare time histories that are outputs of simulation models to time histories from experimental tests with emphasis on vehicle safety applications. We focus on quantifying discrepancy between time histories as the latter constitute the predominant form of responses of interest in vehicle safety considerations. First we evaluate popular measures used to quantify discrepancy between time histories in fields such as statistics, computational mechanics, signal processing, and data mining. Then we propose a structured combination of some of these measures and define a comprehensive metric that encapsulates the important aspects of time history comparison. The new metric classifies error components associated with three physically meaningful characteristics (phase, magnitude and topology), and utilizes norms, cross-correlation measures and algorithms such as dynamic time warping to quantify discrepancies. Two case studies demonstrate that the proposed metric seems to be more consistent than existing metrics. It is also shown how the metric can be used in conjunction with ratings from subject matter experts to build regression-based validation models
|
|
| 3. |
- Ujvari, Beata, et al.
(författare)
-
Experimental studies of blowfly (Calliphora stygia) longevity: A little dietary fat is beneficial but too much is detrimental
- 2009
-
Ingår i: Comparative Biochemistry and Physiology A. - : Elsevier BV. - 1531-4332. ; 154:3, s. 383-388
-
Tidskriftsartikel (refereegranskat)abstract
- This paper is one in a series of experimental studies on the effects of food composition on aging and longevity, using the golden-haired blowfly Calliphora stygia as the animal model Here we examine how diet. fat content affects blowfly life history traits such as longevity, reproduction, feeding rate, body mass, total fat content and membrane fatty acid composition. The highest median and maximum longevity was observed in blowflies fed on low fat diets, while high-fat diets caused more rapid death of the blowflies. A major result was that blowflies feeding on the lowest fat diet had the highest maximal lifespan demonstrating that low levels of diet fat enhanced blowfly lifespan. Diet also influenced gender-specific mortality rates; females lived longer on a high-fat diet, while males lived longer on a low fat diet. Furthermore, we provide data for and explain how blowfly feeding rates, egg production and male harassment affected blowfly longevity. Our results highlight the need for further studies to understand how dietary fats are metabolised and utilised in the golden-haired blowfly. (C) 2009 Elsevier Inc. All rights reserved.
|
|
