A Modular Converter- and Signal-Processing-Platform for Academic Research in the Field of Power Electronics

For academic research it is mandatory that the theoretical evaluation and modelling of new control methods, modulation schemes, electrical machines, power electronic topologies, etc. is validated with accurate measurements. To guarantee a high quality and high performance research it is necessary to have a modular, scalable, user-friendly, adaptable and affordable system. This allows to put the focus on the research topics themselves rather than spending a high effort on the pure implementation of the theoretical research results. The system described in this paper consists of a software environment/toolchain and a hardware platform. The hardware platform can be subdivided into a power electronics platform and a System on Chip based signal processing system. Besides the hardware platform also a user-friendly software environment/toolchain for modelbased research is developed and illustrated in this paper. This new system enables rapid-prototyping of new algorithms, hardware and topologies

Impact of Different Curricular Approaches to Ethics Education on Ethical Reasoning Ability

National Science FoundationPeer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/86116/1/E3_ASEE_Curricular_2011.pd

Outcomes of engaging engineering undergraduates in co-curricular experiences

The effects of involvement in co-curricular experiences (i.e. internships, co-ops, service projects, and clubs and organizations) on student persistence in college is well documented in the education literature. What remains unclear are the specific ways that involvement influences the development of engineering undergraduate students. We found that when engineering students are involved in co-curricular experiences they exhibit greater leadership skills, are more thoughtful about their ethical decisions, and can articulate how involvement influences their ethical development. In this paper, we explore outcomes of participating in co-curricular experiences for engineering students at four undergraduate focused institutions.National Science FoundationPeer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/86117/1/E3_ASEE_Cocurricular_2011.pd

We can’t get no satisfaction!: The relationship between students’ ethical reasoning and their satisfaction with engineering ethics education

Student satisfaction is a common metric for evaluating classes and other educational programs, and sometimes that satisfaction is seen as a proxy for effectiveness of those programs. For this paper, we examine student satisfaction within the context of engineering ethics education, examining the relationship between student satisfaction and ethical reasoning ability. As part of a national study of ethics education, we draw on survey data from 3,914 undergraduate engineering students, and results suggest that higher levels of ethical reasoning actually predict lower levels of satisfaction with ethics education. Further, the amount of ethics education and the methods through which it is taught also affect students’ levels of satisfaction.National Science FoundationPeer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/86096/1/E3_ASEE_Satisfaction_2011.pd

Hubble Space Telescope Imaging of Lyman Alpha Emission at z=4.4

We present the highest redshift detections of resolved Lyman alpha emission, using Hubble Space Telescope/ACS F658N narrowband-imaging data taken in parallel with the Wide Field Camera 3 Early Release Science program in the GOODS CDF-S. We detect Lyman alpha emission from three spectroscopically confirmed z = 4.4 Lyman alpha emitting galaxies (LAEs), more than doubling the sample of LAEs with resolved Lyman alpha emission. Comparing the light distribution between the rest-frame ultraviolet continuum and narrowband images, we investigate the escape of Lyman alpha photons at high redshift. While our data do not support a positional offset between the Lyman alpha and rest-frame ultraviolet (UV) continuum emission, the half-light radii in two out of the three galaxies are significantly larger in Lyman alpha than in the rest-frame UV continuum. This result is confirmed when comparing object sizes in a stack of all objects in both bands. Additionally, the narrowband flux detected with HST is significantly less than observed in similar filters from the ground. These results together imply that the Lyman alpha emission is not strictly confined to its indigenous star-forming regions. Rather, the Lyman alpha emission is more extended, with the missing HST flux likely existing in a diffuse outer halo. This suggests that the radiative transfer of Lyman alpha photons in high-redshift LAEs is complicated, with the interstellar-medium geometry and/or outflows playing a significant role in galaxies at these redshifts.Comment: Submitted to the Astrophysical Journal. 11 pages, 10 figure

Metal-enriched halo gas across galaxy overdensities over the last 10 billion years

We present a study of metal-enriched halo gas traced by Mg II and C IV absorption at z 1. It is clear from our results that environmental processes have a significant impact on the distribution of metals around galaxies and need to be fully accounted for when analysing correlations between gaseous haloes and galaxy properties

A comparison of observed and simulated absorption from H i, C iv, and Si iv around z ≈ 2 star-forming galaxies suggests redshift–space distortions are due to inflows

We study H I and metal-line absorption around z ≈ 2 star-forming galaxies by comparing an analysis of data from the Keck Baryonic Structure Survey to mock spectra generated from the Evolution and Assembly of Galaxies and their Environments (EAGLE) cosmological, hydrodynamical simulations. We extract sightlines from the simulations and compare the properties of the absorption by H I, C IV, and Si IV around simulated and observed galaxies using pixel optical depths. We mimic the resolution, pixel size, and signal-to-noise ratio of the observations, as well as the distributions of impact parameters and galaxy redshift errors. We find that the EAGLE reference model is in excellent agreement with the observations. In particular, the simulation reproduces the high metal-line optical depths found at small galactocentric distances, the optical depth enhancements out to impact parameters of 2 proper Mpc, and the prominent redshift–space distortions which we find are due to peculiar velocities rather than redshift errors. The agreement is best for halo masses ∼1012.0 M⊙, for which the observed and simulated stellar masses also agree most closely. We examine the median ion mass-weighted radial gas velocities around the galaxies, and find that most of the gas is infalling, with the infall velocity depending on halo rather than stellar mass. From this, we conclude that the observed redshift–space distortions are predominantly caused by infall rather than outflows

A Multigenerational View of Inequality

The study of intergenerational mobility and most population research are governed by a two-generation (parent-to-offspring) view of intergenerational influence, to the neglect of the effects of grandparents and other ancestors and nonresident contemporary kin. While appropriate for some populations in some periods, this perspective may omit important sources of intergenerational continuity of family-based social inequality. Social institutions, which transcend individual lives, help support multigenerational influence, particularly at the extreme top and bottom of the social hierarchy, but to some extent in the middle as well. Multigenerational influence also works through demographic processes because families influence subsequent generations through differential fertility and survival, migration, and marriage patterns, as well as through direct transmission of socioeconomic rewards, statuses, and positions. Future research should attend more closely to multigenerational effects; to the tandem nature of demographic and socioeconomic reproduction; and to data, measures, and models that transcend coresident nuclear families

Differential Proteome Analysis of Bone Marrow Mesenchymal Stem Cells from Adolescent Idiopathic Scoliosis Patients

Adolescent idiopathic scoliosis (AIS) is a complex three-dimensional deformity of the spine. The cause and pathogenesis of scoliosis and the accompanying generalized osteopenia remain unclear despite decades of extensive research. In this study, we utilized two-dimensional fluorescence difference gel electrophoresis (2D-DIGE) coupled with mass spectrometry (MS) to analyze the differential proteome of bone marrow mesenchymal stem cells (BM-MSCs) from AIS patients. In total, 41 significantly altered protein spots were detected, of which 34 spots were identified by MALDI-TOF/TOF analysis and found to represent 25 distinct gene products. Among these proteins, five related to bone growth and development, including pyruvate kinase M2, annexin A2, heat shock 27 kDa protein, γ-actin, and β-actin, were found to be dysregulated and therefore selected for further validation by Western blot analysis. At the protein level, our results supported the previous hypothesis that decreased osteogenic differentiation ability of MSCs is one of the mechanisms leading to osteopenia in AIS. In summary, we analyzed the differential BM-MSCs proteome of AIS patients for the first time, which may help to elucidate the underlying molecular mechanisms of bone loss in AIS and also increase understanding of the etiology and pathogenesis of AIS