A micro-accelerometer MDO benchmark problem

Many optimization and coordination methods for multidisciplinary design optimization (MDO) have been proposed in the last three decades. Suitable MDO benchmark problems for testing and comparing these methods are few however. This article presents a new MDO benchmark problem based on the design optimization of an ADXL150 type lateral capacitive micro-accelerometer. The behavioral models describe structural and dynamic effects, as well as electrostatic and amplification circuit contributions. Models for important performance indicators such as sensitivity, range, noise, and footprint area are presented. Geometric and functional constraints are included in these models to enforce proper functioning of the device. The developed models are analytical, and therefore highly suitable for benchmark and educational purposes. Four different problem decompositions are suggested for four design cases, each of which can be used for testing MDO coordination algorithms. As a reference, results for an all-in-one implementation, and a number of augmented Lagrangian coordination algorithms are given. © 2009 The Author(s)

Compromise Based Evolutionary Multiobjective Optimization Algorithm for Multidisciplinary Optimization

International audienceMultidisciplinary Design Optimization deals with engineering problems composed of several sub-problems - called disciplines - that can have antagonist goals and thus require to find compromise solutions. Moreover, the sub-problems are often multiobjective optimization problems. In this case, the compromise solutions between the disciplines are often considered as compromises between all objectives of the problem, which may be not relevant in this context. We propose two alternative definitions of the compromise between disciplines. Their implementations within the well-known NSGA-II algorithm are studied and results are discussed

Target Exploration for Disconnected Feasible Regions in Enterprise-Driven Multilevel Product Design

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/77105/1/AIAA-13908-831.pd

Internal oxygen transport in Rumex species and its significance for respiration under hypoxic conditions

Contains fulltext : 6440.pdf (publisher's version ) (Open Access

Sex and freezing of gait in Parkinson's disease: a systematic review and meta-analysis

Contains fulltext : 232512.pdf (Publisher’s version ) (Open Access)OBJECTIVE: It is unknown how sex affects the prevalence of freezing of gait (FOG). We conducted a systematic review and meta-analysis to establish the sex-specific prevalence of FOG in persons with Parkinson's disease (PD). In addition, we investigated whether men and women were represented accurately in intervention trials targeting FOG. METHODS: We queried the EMBASE and PubMed databases and identified 2637 articles. Of these, 16 epidemiological studies were included in the meta-analysis, and 51 intervention studies were included in the comparative analysis. RESULTS: In total, 5702 persons were included in the final meta-analysis of epidemiological studies. The pooled estimate of overall FOG prevalence was 43% [95% CI 33-53%]. We found no difference in FOG prevalence between men [44% (34-54%)] and women [42% (31-52%)] with PD. However, women were markedly underrepresented in intervention trials targeting FOG, with an average proportion of only 29.6% of women in trial populations. The percentage of women included in trials was similar across intervention types but differed greatly across geographical regions. CONCLUSION: Sex is not a predictor of FOG. This could aid clinicians in counseling persons with PD about FOG. Importantly, a global effort is needed to include more women into clinical trials. Given the skewed distribution of men and women included in intervention trials targeting FOG, caution might be warranted when extrapolating results from FOG trials to women

Oxygen uptake by roots of Rumex species at different temperatures : the relative importance of diffusive resistance and enzyme kinetics

Contains fulltext : 6452.pdf (publisher's version ) (Open Access