Bowlin M.S.,University of MichiganDearborn |
Enstrom D.A.,Illinois Natural History Survey |
Murphy B.J.,University of MichiganDearborn |
Plaza E.,University of MichiganDearborn |
And 2 more authors.
Auk | Year: 2015
Describing and then explaining individual behavior during migration can help us to understand why (on both proximate and ultimate levels) birds migrate; the altitude(s) at which migratory birds fly, for example, can have far-reaching consequences. However, to date, no fine-scale, full-flight altitude data have been available for small (<100 g) migratory birds. We tracked 7 Swainson's Thrushes (Catharus ustulatus) carrying altimeters from takeoff until landing or near-landing during 9 migratory flights. The average recorded flight altitude for the 9 flights was 673.0 ± 523.2 m (mean ± SD); average maximum flight altitude for the 9 flights was 1,199.5 ± 862.7 m (range: 319.22,744.5 m). Initial ascent rates (0.42 ± 0.15 m s-1, n=8) matched predictions; final descent rates were 0.55 ± 0.30 m s-1 (n=5). Contrary to expectations, the thrushes made numerous (9.33 ± 4.42), significant (>100 m) altitude adjustments during their flights (1.44 hr-1), not including initial ascent and final descent. The repeated changes in flight altitude that we observed should cause these birds to use more energy than they would if they flew at or near a single altitude for several hours at a time. We speculate that these altitude modifications may result from variation in atmospheric conditions or from the birds descending toward anthropogenic light sources during the flights. © 2015 American Ornithologists' Union.
Liu Y.,Georgia State University |
Khoshgoftaar T.M.,Florida Atlantic University |
Seliya N.,University of MichiganDearborn
IEEE Transactions on Software Engineering | Year: 2010
A novel search-based approach to software quality modeling with multiple software project repositories is presented. Training a software quality model with only one software measurement and defect data set may not effectively encapsulate quality trends of the development organization. The inclusion of additional software projects during the training process can provide a cross-project perspective on software quality modeling and prediction. The genetic-programming-based approach includes three strategies for modeling with multiple software projects: Baseline Classifier, Validation Classifier, and Validation-and-Voting Classifier. The latter is shown to provide better generalization and more robust software quality models. This is based on a case study of software metrics and defect data from seven real-world systems. A second case study considers 17 different (nonevolutionary) machine learners for modeling with multiple software data sets. Both case studies use a similar majority-voting approach for predicting fault-proneness class of program modules. It is shown that the total cost of misclassification of the search-based software quality models is consistently lower than those of the non-search-based models. This study provides clear guidance to practitioners interested in exploiting their organization's software measurement data repositories for improved software quality modeling. © 2010 IEEE.
Peer J.W.,University of MichiganDearborn |
Hillman S.B.,Wayne State University
Journal of Intellectual Disabilities | Year: 2012
Research reveals that parents of individuals with intellectual disabilities experience more stress than parents of persons of normal development. The majority of previous research has measured direct relationships between stress variables and stress perception and little attention has been given to the impact of mediating variables. The present study utilized an indirect pathway model to examine the mediating influence of coping style on the relationship between social support, severity of child disability, parental optimism and stress perception for these parents. Parents of individuals receiving mental health services through an agency in Southeastern Michigan participated in the study. Results indicated that coping style partially mediated the relationship between social support and stress perception for parents of individuals with intellectual disabilities. © SAGE Publications 2012.