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1. Joint computational design of workspaces and workplans

   https://doi.org/10.1145/3478513.3480500  

   Zhang, Yongqi; Huang, Haikun; Plaku, Erion; Yu, Lap-Fai (December 2021, ACM Transactions on Graphics)

   Humans assume different production roles in a workspace. On one hand, humans design workplans to complete tasks as efficiently as possible in order to improve productivity. On the other hand, a nice workspace is essential to facilitate teamwork. In this way, workspace design and workplan design complement each other. Inspired by such observations, we propose an automatic approach to jointly design a workspace and a workplan. Taking staff properties, a space, and work equipment as input, our approach jointly optimizes a workspace and a workplan, considering performance factors such as time efficiency and congestion avoidance, as well as workload factors such as walk effort, turn effort, and workload balances. To enable exploration of design trade-offs, our approach generates a set of Pareto-optimal design solutions with strengths on different objectives, which can be adopted for different work scenarios. We apply our approach to synthesize workspaces and workplans for different workplaces such as a fast food kitchen and a supermarket. We also extend our approach to incorporate other common work considerations such as dynamic work demands and accommodating staff members with different physical capabilities. Evaluation experiments with simulations validate the efficacy of our approach for synthesizing effective workspaces and workplans. 

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2. FPGAs-as-a-Service Toolkit (FaaST)

   https://doi.org/10.1109/H2RC51942.2020.00010  

   Rankin, Dylan; Krupa, Jeffrey; Harris, Philip; Flechas, Maria Acosta; Holzman, Burt; Klijnsma, Thomas; Pedro, Kevin; Tran, Nhan; Hauck, Scott; Hsu, Shih-Chieh; et al (November 2020, 2020 IEEE/ACM International Workshop on Heterogeneous High-performance Reconfigurable Computing (H2RC))

   null (Ed.)

   Computing needs for high energy physics are already intensive and are expected to increase drastically in the coming years. In this context, heterogeneous computing, specifically as-a-service computing, has the potential for significant gains over traditional computing models. Although previous studies and packages in the field of heterogeneous computing have focused on GPUs as accelerators, FPGAs are an extremely promising option as well. A series of workflows are developed to establish the performance capabilities of FPGAs as a service. Multiple different devices and a range of algorithms for use in high energy physics are studied. For a small, dense network, the throughput can be improved by an order of magnitude with respect to GPUs as a service. For large convolutional networks, the throughput is found to be comparable to GPUs as a service. This work represents the first open-source FPGAs-as-a-service toolkit. 

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3. FPGAs-as-a-Service Toolkit (FaaST)

   Rankin, Dylan; Krupa, Jeffrey; Harris, Philip; Flechas, Maria; Holzman, Burt; Klijnsma, Thomas; Pedro, Kevin; Tran, Nhan; Hauck, Scott; Hsu, Shih-Chieh; et al (October 2020, ArXivorg)

   null (Ed.)

   Computing needs for high energy physics are already intensive and are expected to increase drastically in the coming years. In this context, heterogeneous computing, specifically as-a-service computing, has the potential for significant gains over traditional computing models. Although previous studies and packages in the field of heterogeneous computing have focused on GPUs as accelerators, FPGAs are an extremely promising option as well. A series of workflows are developed to establish the performance capabilities of FPGAs as a service. Multiple different devices and a range of algorithms for use in high energy physics are studied. For a small, dense network, the throughput can be improved by an order of magnitude with respect to GPUs as a service. For large convolutional networks, the throughput is found to be comparable to GPUs as a service. This work represents the first open-source FPGAs-as-a-service toolkit. 

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4. Debugging pedagogies: Helping middle school students learn to get unstuck with physical computing systems.

   Hennessy Elliott, C.; Gendreau Chakarov, A.; Bush, J.; Recker, M. (January 2022, Annual meeting program American Educational Research Association)

   The paper draws on data collected during an inquiry-oriented instructional approach in which students learn to program a sensor-based physical computing system to collect and display meaningful data from the world around them. As part of one instructional unit (Sensor Immersion Unit) students debug their system when it does not work as they expect it to. We present a case study of how one teacher (Gabrielle) acted as a caring collaborator with students as they addressed hardware and software problems. This included modeling and articulating a regular systematic approach to becoming “unstuck,” which we map in analysis. Gabrielle’s approach to supporting students, or her debugging pedagogy, positions debugging as core computing practice rather than as a means to overcome failure. 

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5. Carbon Impurity Minimization of Solution-Processed, Thin-Film Photovoltaics via Ligand Engineering of CuInS2 Nanoparticles

   https://doi.org/10.1021/acsaem.3c01922  

   Hayes, Daniel C; Langdon, Samantha A; Spilker, Robert M; Agrawal, Rakesh (February 2024, ACS Applied Energy Materials)

   Colloidal semiconductor nanoparticles (NPs) have long been used as a reliable method for depositing thin films of semiconductor materials for applications, such as photovoltaics via solution-processed means. Traditional methods for synthesizing colloidal NPs often utilize heavy, long-chain organic species to serve as surface ligands, which, during the fabrication of selenized chalcogenide films, leaves behind an undesirable carbonaceous residue in the film. In an effort to minimize these residues, this work looks at using N-methyl-2-pyrrolidone (NMP) as an alternative to the traditional species used as surface ligands. In addition to serving as a primary ligand, NMP also serves as the reaction medium and coating solvent for fabricating CuInS2 (CIS) NPs and thin-film solar cells. Through the use of the NMP-based synthesis, a substantial reduction in the number of carbonaceous residues was observed in selenized films. Additionally, the resulting fine-grain layer at the bottom of the film was observed to exhibit a larger average grain size and increased chalcopyrite character over those of traditionally prepared films, presumably as a result of the reduced carbon content. As a result, a gallium-free CuIn(S,Se)2 device was shown to achieve power-conversion efficiencies of over 11% as well as possessing exceptional carrier generation capabilities with a short-circuit current density (JSC) of 41.6 mA/cm2, which is among the highest for the CIGSSe family of devices fabricated from solution-processed methods. 

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