207 research outputs found

    How Engineering Education Guilds are Expanding our Understanding of Propagation in Engineering Education

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    Background: The National Science Foundation (NSF) and other organizations have spent millions of dollars each year supporting well-designed educational innovations that positively impact the undergraduate engineering students who encounter them. However, many of these pedagogical innovations never experience widespread adoption. To further the ability of innovation developers to advance engineering education practice and achieve sustained adoption of their innovations, this paper focuses on exploring how one community-based model, engineering education guilds, fosters propagation across institutions and individuals. Engineering education guilds seek to work at the forefront of educational innovation by creating networks of instructor change-agents who design and implement a particular innovation in their own context. The guilds of interest are the Consortium to Promote Reflection in Engineering Education (CPREE) and the Kern Entrepreneurial Engineering Network (KEEN). With these guilds as exemplars, this study’s purpose is (1) to articulate how the approaches of engineering education guilds align with existing literature on supporting sustained adoption of educational innovations and (2) to identify how these approaches can advance the STEM education community’s discussion of propagation practices through the use of the Designing for Sustained Adoption Assessment Instrument (DSAAI). The DSAAI is a conceptual framework based on research in sustained adoption of pedagogical innovations. It has previously been previously used in the form of a rubric to analyze dissemination and propagation plans of NSF educational grant recipients and was shown been shown to predict the effectiveness of those propagation plans. Results: Through semi-structured interviews with two leaders from each guild, we observed strong alignment between the structures of CRPEE and KEEN and evidence-based sustained adoption characteristics. For example, both guilds identified their intended audience early in their formation, developed and implemented extensive plans for engaging and supporting potential adopters, and accounted for the complexity of the higher education landscape and their innovations in their propagation plans. Conclusions: Our results suggest that guilds could provide another approach to innovation, as their structures can be aligned with evidence-based methods for propagating pedagogical innovations. Additionally, while the DSAAI captures many of the characteristics of a well-designed propagation strategy, there are additional components that emerged as successful strategies used by the CPREE and KEEN guild leaders. These strategies could and should be considered as educational innovators work to encourage adoption of their innovations, including having mutual accountability among adopters and connecting adoption of innovations to faculty reward structures in the form of recognition and funding

    Integrating Entrepreneurial Mindset in a Multidisciplinary Course on Engineering Design and Technical Communication

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    The engineering curriculum at XXXX University includes a sophomore level two-course sequence (required for engineering students in all disciplines) in which the primary learning outcomes are engineering design and technical communication. These courses are team-taught by faculty from Engineering and from Communications, specifically, Writing Arts in the fall and Public Speaking in the spring. Historically, the fall course has featured three major course deliverables: (1) a “research sequence” consisting of a rhetorical analysis, and annotated bibliography and a literature review, (2) a humanities assignment in which students explore the impact of technology on societal needs, and (3) laboratory and design reports stemming from hands-on engineering projects completed in lab. During the summer of 2019, the faculty team re-designed each of these three major course deliverables, with the goal of fostering an Entrepreneurial Mindset in students and leveraging synergies between the Entrepreneurial Mindset and the existing goals of the course (engineering design and technical communication). In particular, the faculty team created a new linkage between the research sequence and the humanities assignment. The research sequence is built around the U.N.’s Sustainable Development Goals; each student chooses one of the goals to explore through their individual rhetorical analysis, annotated bibliography, and literature review. The humanities assignment is a team project in which students explore solutions to sustainability problems on the campus of XXXX University. Different sections of the course will use different engineering projects, but the faculty team has crafted a set of guidelines for the projects to ensure some uniformity of experience and expectations across the sections. The faculty team also developed rubrics that will be used to evaluate student performance on these re-designed assignments. The new assignments are being integrated into the Fall 2019 offering of Sophomore Engineering Clinic. This paper will give a detailed description of each of the assignments and how they are designed to align with the goal of fostering an Entrepreneurial Mindset. The paper will also present assessment data that will be collected throughout the Fall 2019 semester

    Harnessing catalytic pumps for directional delivery of microparticles in microchambers

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    The directed transport of microparticles in microfluidic devices is vital for efficient bioassays and fabrication of complex microstructures. There remains, however, a need for methods to propel and steer microscopic cargo that do not require modifying these particles. Using theory and experiments, we show that catalytic surface reactions can be used to deliver microparticle cargo to specified regions in microchambers. Here reagents diffuse from a gel reservoir and react with the catalyst-coated surface. Fluid density gradients due to the spatially varying reagent concentration induce a convective flow, which carries the suspended particles until the reagents are consumed. Consequently, the cargo is deposited around a specific position on the surface. The velocity and final peak location of the cargo can be tuned independently. By increasing the local particle concentration, highly sensitive assays can be performed efficiently and rapidly. Moreover, the process can be repeated by introducing fresh reagent into the microchamber

    Investigation of the process energy demand in polymer extrusion: A brief review and an experimental study

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    YesExtrusion is one of the fundamental production methods in the polymer processing industry and is used in the production of a large number of commodities in a diverse industrial sector. Being an energy intensive production method, process energy efficiency is one of the major concerns and the selection of the most energy efficient processing conditions is a key to reducing operating costs. Usually, extruders consume energy through the drive motor, barrel heaters, cooling fans, cooling water pumps, gear pumps, etc. Typically the drive motor is the largest energy consuming device in an extruder while barrel/die heaters are responsible for the second largest energy demand. This study is focused on investigating the total energy demand of an extrusion plant under various processing conditions while identifying ways to optimise the energy efficiency. Initially, a review was carried out on the monitoring and modelling of the energy consumption in polymer extrusion. Also, the power factor, energy demand and losses of a typical extrusion plant were discussed in detail. The mass throughput, total energy consumption and power factor of an extruder were experimentally observed over different processing conditions and the total extruder energy demand was modelled empirically and also using a commercially available extrusion simulation software. The experimental results show that extruder energy demand is heavily coupled between the machine, material and process parameters. The total power predicted by the simulation software exhibits a lagging offset compared with the experimental measurements. Empirical models are in good agreement with the experimental measurements and hence these can be used in studying process energy behaviour in detail and to identify ways to optimise the process energy efficiency

    Thin Film PZT-Based PMUT Arrays for Deterministic Particle Manipulation

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    Lead zirconate titanate (PZT) based piezoelectric micromachined ultrasonic transducers (PMUTs) for particle manipulation applications were designed, fabricated, characterized and tested. The PMUTs had a diaphragm diameter of 60 lm, a resonant frequency of ∼ 8 MHz and an operational bandwidth of 62.5%. Acoustic pressure output in water was 9.5 kPa at 7.5 mm distance from a PMUT element excited with a unipolar waveform at 5 Vpp. The element consisted of 20 diaphragms connected electrically in parallel. Particle trapping of 4 lm silica beads was shown to be possible with 5 Vpp unipolar excitation. Trapping of multiple beads by a single element and deterministic control of particles via acoustophoresis without the assistance of microfluidic flow were demonstrated. It was found that the particles move towards diaphragm areas of highest pressure, in agreement with literature and simulations. Unique bead patterns were generated at different driving frequencies and were formed at frequencies up to 60 MHz, much higher than the operational bandwidth. Levitation planes were generated above 30 MHz driving frequency

    In-situ local phase-transitioned MoSe2 in La0.5Sr0.5CoO3-?? heterostructure and stable overall water electrolysis over 1000 hours

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    Developing efficient bifunctional catalysts for overall water splitting that are earth-abundant, cost-effective, and durable is of considerable importance from the practical perspective to mitigate the issues associated with precious metal-based catalysts. Herein, we introduce a heterostructure comprising perovskite oxides (La0.5Sr0.5CoO3?????) and molybdenum diselenide (MoSe2) as an electrochemical catalyst for overall water electrolysis. Interestingly, formation of the heterostructure of La0.5Sr0.5CoO3????? and MoSe2 induces a local phase transition in MoSe2, 2???H to 1???T phase, and more electrophilic La0.5Sr0.5CoO3????? with partial oxidation of the Co cation owing to electron transfer from Co to Mo. Together with these synergistic effects, the electrochemical activities are significantly improved for both hydrogen and oxygen evolution reactions. In the overall water splitting operation, the heterostructure showed excellent stability at the high current density of 100???mA???cm???2 over 1,000???h, which is exceptionally better than the stability of the state-of-the-art platinum and iridium oxide couple

    Gestational Diabetes Is Characterized by Reduced Mitochondrial Protein Expression and Altered Calcium Signaling Proteins in Skeletal Muscle

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    The rising prevalence of gestational diabetes mellitus (GDM) affects up to 18% of pregnant women with immediate and long-term metabolic consequences for both mother and infant. Abnormal glucose uptake and lipid oxidation are hallmark features of GDM prompting us to use an exploratory proteomics approach to investigate the cellular mechanisms underlying differences in skeletal muscle metabolism between obese pregnant women with GDM (OGDM) and obese pregnant women with normal glucose tolerance (ONGT). Functional validation was performed in a second cohort of obese OGDM and ONGT pregnant women. Quantitative proteomic analysis in rectus abdominus skeletal muscle tissue collected at delivery revealed reduced protein content of mitochondrial complex I (C-I) subunits (NDUFS3, NDUFV2) and altered content of proteins involved in calcium homeostasis/signaling (calcineurin A, α1-syntrophin, annexin A4) in OGDM (n = 6) vs. ONGT (n = 6). Follow-up analyses showed reduced enzymatic activity of mitochondrial complexes C-I, C-III, and C-IV (−60–75%) in the OGDM (n = 8) compared with ONGT (n = 10) subjects, though no differences were observed for mitochondrial complex protein content. Upstream regulators of mitochondrial biogenesis and oxidative phosphorylation were not different between groups. However, AMPK phosphorylation was dramatically reduced by 75% in the OGDM women. These data suggest that GDM is associated with reduced skeletal muscle oxidative phosphorylation and disordered calcium homeostasis. These relationships deserve further attention as they may represent novel risk factors for development of GDM and may have implications on the effectiveness of physical activity interventions on both treatment strategies for GDM and for prevention of type 2 diabetes postpartum

    Recent advances in unveiling active sites in molybdenum sulfide-based electrocatalysts for the hydrogen evolution reaction

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    Hydrogen has received significant attention as a promising future energy carrier due to its high energy density and environmentally friendly nature. In particular, the electrocatalytic generation of hydrogen fuel is highly desirable to replace current fossil fuel-dependent hydrogen production methods. However, to achieve widespread implementation of electrocatalytic hydrogen production technology, the development of highly active and durable electrocatalysts based on Earth-abundant elements is of prime importance. In this context, nanostructured molybdenum sulfides (MoS x ) have received a great deal of attention as promising alternatives to precious metal-based catalysts. In this focus review, we summarize recent efforts towards identification of the active sites in MoS x -based electrocatalysts for the hydrogen evolution reaction (HER). We also discuss recent synthetic strategies for the engineering of catalyst structures to achieve high active site densities. Finally, we suggest ongoing and future research challenges in the design of advanced MoS x -based HER electrocatalysts
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