Investigating Student Learning of Analog Electronics

Instruction in analog electronics is an integral component of many physics and engineering programs, and is typically covered in courses beyond the first year. While extensive research has been conducted on student understanding of introductory electric circuits, to date there has been relatively little research on student learning of analog electronics in either physics or engineering courses. Given the significant overlap in content of courses offered in both disciplines, this study seeks to strengthen the research base on the learning and teaching of electric circuits and analog electronics via a single, coherent investigation spanning both physics and engineering courses. This dissertation has three distinct components, each of which serves to clarify ways in which students think about and analyze electronic circuits. The first component is a broad investigation of student learning of specific classes of analog circuits (e.g., loaded voltage dividers, diode circuits, and operational amplifier circuits) across courses in both physics and engineering. The second component of this dissertation is an in-depth study of student understanding of bipolar junction transistors and transistor circuits, which employed the systematic, research-based development of a suite of research tasks to pinpoint the specific aspects of transistor circuit behavior that students struggle with the most after instruction. The third component of this dissertation focuses more on the experimental components of electronics instruction by examining in detail the practical laboratory skill of troubleshooting. Due to the systematic, cross-disciplinary nature of the research documented in this dissertation, this work will strengthen the research base on the learning and teaching of electronics and will contribute to improvements in electronics instruction in both physics and engineering departments. In general, students did not appear to have developed a coherent, functional understanding of many key circuits after all instruction. Students also seemed to struggle with the application of foundational circuits concepts in new contexts, which is consistent with existing research on other topics. However, students did frequently use individual elements of productive reasoning when thinking about electric circuits. Recommendations, both general and specific, for future research and for electronics instruction are discussed

Investigating the role of model-based reasoning while troubleshooting an electric circuit

We explore the overlap of two nationally-recognized learning outcomes for physics lab courses, namely, the ability to model experimental systems and the ability to troubleshoot a malfunctioning apparatus. Modeling and troubleshooting are both nonlinear, recursive processes that involve using models to inform revisions to an apparatus. To probe the overlap of modeling and troubleshooting, we collected audiovisual data from think-aloud activities in which eight pairs of students from two institutions attempted to diagnose and repair a malfunctioning electrical circuit. We characterize the cognitive tasks and model-based reasoning that students employed during this activity. In doing so, we demonstrate that troubleshooting engages students in the core scientific practice of modeling.Comment: 20 pages, 6 figures, 4 tables; Submitted to Physical Review PE

The role of metacognition in troubleshooting: an example from electronics

Students in physics laboratory courses, particularly at the upper division, are often expected to engage in troubleshooting. Although there are numerous ways in which students may proceed when diagnosing a problem, not all approaches are equivalent in terms of providing meaningful insight. It is reasonable to believe that metacognition, by assisting students in making informed decisions, is an integral component of effective troubleshooting. We report on an investigation of authentic student troubleshooting in the context of junior-level electronics courses at two institutions. Think-aloud interviews were conducted with pairs of students as they attempted to repair a malfunctioning operational-amplifier circuit. Video data from the interviews have been analyzed to examine the relationship between each group's troubleshooting activities and instances of socially mediated metacognition. We present an analysis of a short episode from one interview.Comment: 4 pages, 1 figure; Submitted to 2015 PERC Proceeding

Fragmented Authority from Ancien Régime to Modernity: a Quantitative Analysis

This paper performs a systematic analysis that examines institutional fragmentation in terms of customs tariffs within states west of the Rhine from 1700 to 1815 and between states east of the Rhine from 1815 to 1871. Internal customs zones are measured in two ways: physical size and urban population. Both methods use 175 sample cities as described by De Vries (1984) in England, France, the Netherlands, and Spain as the basic unit of account. The results indicate that customs zones west of the Rhine were small prior to the French Revolution but grew dramatically from 1789 onwards. They thus provide definitive evidence of divided authority in Ancien Régime Europe. The measurement of external customs zones uses 117 sample cities in the German and Italian territories. The findings indicate a remarkable degree of institutional consolidation between states east of the Rhine over the 1800s

Afferent neurourology: A novel paradigm

The term “afferent neurourology” is introduced to describe the study of sensory processing related to the genitourinary tract. Urologic disorders that are characterized by abnormal sensory processing are reviewed, and unique challenges to our understanding of these disorders are described. A paradigm which separates afferent urologic disorders from efferent disorders and structural abnormalities is presented. Neurourol. Urodynam. 29:S29–S31, 2010. © 2010 Wiley-Liss, Inc.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/71357/1/20792_ftp.pd

Can we detect local helioseismic parameter shifts in coronal holes?

Changes in helioseismic mode parameters in active regions and across the solar disk are well documented, but local magnetic activity and geometric effects may not account for all of the scatter seen in the results. We use results from theHelioseismic and Magnetic Imagerring-diagram pipeline for Carrington rotation 2113 to look for differences in mode amplitude and frequency between coronal holes and other quiet-Sun regions. While we do not find a systematic difference, the results do suggest that the correlation between magnetic activity index and mode parameters shows less scatter in coronal hole regions than in general quiet Sun

Curie: Constraining Solar System Bombardment Using In Situ Radiometric Dating

The Curie mission would constrain the existence of the putative cataclysm by determining the age of samples directly sourced from the impact melt sheet of a major pre-Imbrium lunar basin. The measurements would also enable further understanding of lunar evolution by characterizing new lunar lithologies far from the Apollo and Luna landing sites, including the very low-Ti basalts in Mare Crisium and potential olivine rich lithologies in the margins of both Mare Nectaris and Mars Crisium. Equipped with a mass spectrometer and a LIBS, Curie would also be well-placed to survey volatile components of the lunar regolith, including surface-bound hydrogen

A randomized, open-label, multicenter study of the efficacy and safety of intravesical hyaluronic acid and chondroitin sulfate versus dimethyl sulfoxide in women with bladder pain syndrome/interstitial cystitis.

Published onlineJournal ArticleThis is the author accepted manuscript. The final version is available from Wiley via the DOI in this record.AIMS: Intravesical instillation of hyaluronic acid (HA) plus chondroitin sulfate (CS) in women with bladder pain syndrome/interstitial cystitis (BPS/IC) has shown promising results. This study compared the efficacy, safety, and costs of intravesical HA/CS (Ialuril(®) , IBSA) to dimethyl sulfoxide (DMSO). METHODS: Randomized, open-label, multicenter study involving 110 women with BPS/IC. The allocation ratio (HA/CS:DMSO) was 2:1. Thirteen weekly instillations of HA (1.6%)/CS (2.0%) or 50% DMSO were given. Patients were evaluated at 3 (end-of-treatment) and 6 months. Primary endpoint was reduction in pain intensity at 6 months by visual analogue scale (VAS) versus baseline. Secondary efficacy measurements were quality of life and economic analyses. RESULTS: A significant reduction in pain intensity was observed at 6 months in both treatment groups versus baseline (P < 0.0001) in the intention-to-treat population. Treatment with HA/CS resulted in a greater reduction in pain intensity at 6 months compared with DMSO for the per-protocol population (mean VAS reduction 44.77 ± 25.07 vs. 28.89 ± 31.14, respectively; P = 0.0186). There were no significant differences between treatment groups in secondary outcomes. At least one adverse event was reported in 14.86% and 30.56% of patients in the HA/CS and DMSO groups, respectively. There were significantly fewer treatment-related adverse events for HA/CS versus DMSO (1.35% vs. 22.22%; P = 0.001). Considering direct healthcare costs, the incremental cost-effectiveness ratio of HA/CS versus DMSO fell between 3735€/quality-adjusted life years (QALY) and 8003€/QALY. CONCLUSIONS: Treatment with HA/CS appears to be as effective as DMSO with a potentially more favorable safety profile. Both treatments increased health-related quality of life, while HA/CS showed a more acceptable cost-effectiveness profile.This study was sponsored by IBSA Farmaceutici Italia. This assistance was funded by IBSA Institut Biochimique SA