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  1. Free, publicly-accessible full text available February 21, 2024
  2. In this paper we report on the development and testing of hands-on desktop learning modules for transport courses in the Chemical and Mechanical Engineering disciplines. Two modules were developed to demonstrate fluid mechanics-related concepts, while two other modules were created for energy transport in heat exchangers. These devices are small, inexpensive, and made of see-through polycarbonate plastics using injection molding. These desktop learning modules are particularly suitable for use in undergraduate classrooms in conjunction with lectures to illustrate the working mechanism of devices seen in an industrial setting. Experiments are performed to understand the flow behavior and heat transfer performance on these modules. Our results show an excellent agreement for hydraulic head loss, volumetric flow rates, and overall heat transfer coefficients between experimental data and the corresponding theory, justifying the design and use of these devices in the classroom. Furthermore, we have measured student learning gains through pre-and posttests for each module based on in-class implementations at different universities. Assessment of student learning outcomes shows significant improvement in conceptual understanding when these modules are used in the undergraduate class.
    Free, publicly-accessible full text available August 23, 2023
  3. The past twenty years have seen the blossoming of ethics education in undergraduate engineering programs, largely as a response to the large-scale and high-impact engineering disasters that have occurred since the turn of the century. The functional form of this education differs significantly among institutions, and in recent years active learning that demonstrates a strong impact on students’ retention and synthesis of new material have taken hold as the preferred educational methodology. Among active learning strategies, gamified or playful learning has grown in popularity, with substantial evidence indicating that games can increase student participation and social interaction with their classmates and with the subject matter. A key goal of engineering ethics education is for students to learn how to identify, frame, and resolve ethical dilemmas. These dilemmas occur naturally in social situations, in which an individual must reconcile opposing priorities and viewpoints. Thus, it seems natural that as a part of their ethics education, students should discuss contextualized engineering ethical situations with their peers. How these discussions play out, and the manner in which students (particularly first-year engineering students) address and resolve ethical dilemmas in a group setting is the main topic of this research paper. In this study, first-yearmore »engineering students from three universities across the northeastern USA participated in group discussions involving engineering ethical scenarios derived from the Engineering Ethics Reasoning Instrument (EERI) and Toxic Workplaces: A Cooperative Ethics Card Game (a game developed by the researchers). Questions were posed to the student groups, which center upon concepts such as integrity, conflicting obligations, and the contextual nature of ethical decision making. An a priori coding schema based on these concepts was applied to analyze the student responses, based upon earlier iterations of this procedure performed in previous years of the study. The primary results from this research will aim to provide some insight about first-year engineering students' mindsets when identifying, framing, and resolving ethical dilemmas. This information can inform ethics education design and development strategies. Furthermore, the experimental procedure is also designed to provide a curated series of ethical engineering scenarios with accompanying discussion questions that could be adopted in any first-year classroom for instructional and evaluative purposes.« less
    Free, publicly-accessible full text available August 1, 2023
  4. As this NSF LCDLM dissemination, development, and assessment project matures going into our fourth year of support we are moving forward in parallel on several fronts. We are developing and testing an injection-molded shell-and-tube heat exchanger for heat transfer concepts, an evaporative cooler to expand to another industrial-based heat exchange system, and a bead separation module to demonstrate principles of fluid mechanics in blood cell separations applications. We are also comparing experimental data for our miniaturized hydraulic loss and venturi meter LCDLMs to predicted values based on standard industrial correlations. As we develop these new learning components, we are assessing differential gains based on gender and ethnicity, as well as how students learn with existing LCDLMs in a virtual mode with online videos compared to an in-person hands-on mode of instruction.
    Free, publicly-accessible full text available August 23, 2023
  5. Jadamba, B ; Khan, A. A ; Migórski, S ; Sama, M. (Ed.)
  6. Bender, M. ; Gilbert, J. ; Hendrickson, B. ; Sullivan, B. (Ed.)
    We design new serial and parallel approximation algorithms for computing a maximum weight b-matching in an edge-weighted graph with a submodular objective function. This problem is NP-hard; the new algorithms have approximation ratio 1/3, and are relaxations of the Greedy algorithm that rely only on local information in the graph, making them parallelizable. We have designed and implemented Local Lazy Greedy algorithms for both serial and parallel computers. We have applied the approximate submodular b-matching algorithm to assign tasks to processors in the computation of Fock matrices in quantum chemistry on parallel computers. The assignment seeks to reduce the run time by balancing the computational load on the processors and bounding the number of messages that each processor sends. We show that the new assignment of tasks to processors provides a four fold speedup over the currently used assignment in the NWChemEx software on 8000 processors on the Summit supercomputer at Oak Ridge National Lab.