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1. Comparison of Various Theoretical Measures of Aromaticity within Monosubstituted Benzene

   https://doi.org/10.3390/molecules29102260  

   Swain, Caleb K ; Scheiner, Steve ( May 2024 , Molecules)

   The effects of monosubstitution on the aromaticity of benzene are assessed using a number of different quantitative schemes. The ability of the mobile π-electrons to respond to an external magnetic field is evaluated using several variants of the NICS scheme which calculate the shielding of points along the axis perpendicular to the molecule. Another class of measures is related to the drive toward the uniformity of C-C bond lengths and strengths. Several energetic quantities are devised to approximate an aromatic stabilization energy and the tendency of the molecule to maintain planarity. There is a lack of consistency in that the various measures of aromaticity lead to differing conclusions as to the effects of substituents on the aromaticity of the ring.

    

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2. Demo Abstract: An Ultra-Low-Power Custom Integrated Circuit based Sound-Source Localization System

   de Godoy, Daniel ; Xia, Stephen ; Fernandez, Wendy ; Jiang, Xiaofan ; Kinget, Peter R ( April 2018 , IEEE/ACM International Conference on Internet-of-Things Design and Implementation)

   The aim of this demo is to explore the implementation of an ultra-low-power analog-to-feature ASIC to an IoT embedded system. The custom integrated circuit, designed to optimize the power consumption of a traditional sound-source localization systems, is capable of extracting the time-difference of arrival (TDoA) between 4 microphones consuming only 78.2nW. An end-to-end embedded system is presented; a microphone array is connected to the ASIC that converts the TDoA to digital information and sends it to a host computer. A machine-learning algorithm, running in the host, is then used to detect the bearing of the sound-source. During the demonstration, the audience is able to verify the benefits and drawbacks of the custom integrated circuit solution, both in the perspective of the signal-processing performance of the ASIC, and the impact it introduces to the complexity of the system’s integration. 

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3. Vulnerability assessment of Structural Insulated Panels with metal skins subjected to windborne debris impact

   https://doi.org/https://doi.org/10.1016/j.compositesb.2020.108163  

   Saini, D. ; Shafei, B. ( June 2020 , Composites)

   Structural Insulated Panels (SIPs), which consist of a composite of an insulating polymer foam sandwiched between two layers of structural skins, are widely used in residential and commercial buildings. Such panels, in the regions prone to hurricanes and tornadoes, are often exposed to the risk of windborne debris impact. Despite the consequences associated with damage to SIPs, the studies on their perforation resistance and design variables have been rather limited. To address this gap, the current study develops a computational framework to assess the vulnerability of the SIPs of various configurations subjected to a range of windborne debris impact scenarios. For this purpose, impact simulations are conducted to quantify the response and evaluate the extent of damage to the SIPs. The study is further extended to evaluate the effect of various structural details and material properties on the perforation resistance of the SIPs. Based on the simulation results, a set of vulnerability curves are developed for the first time to capture the risk of failure of the SIPs under the windborne debris hazard. This is expected to improve the design of this important category of wall panels, especially to ensure their safety and performance during severe windstorms. 

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4. Voices of experience: Enhancing learning on resilient infrastructure and sustainability through servingness

   Leoncio-Cabán R., Sotomayor R. ( June 2022 , American Society of Engineering Education (ASEE) Annual Conference,)

   In Puerto Rico, the exposure to extreme environmental conditions has become part of a new normal. Because of this, the education of professionals to face this new reality is part of the demands of the academia of the present, and to the core of it the concept of servingness as a tool contribute to the formation of students’ and faculty sensibility to social dynamics connected to the educational experiences. The Resilient Infrastructure and Sustainability Education – Undergraduate Program (RISE-UP), funded by the Hispanic Serving Institution (HSI) program of the National Science Foundation (NSF), has been conceptualized including elements of servingness by addressing aspects connected to the learning experience, leadership identity, critical consciousness, academic and research aspirations, and civic engagement all in the context of Puerto Rico’s current infrastructural needs. This paper addresses those dynamics by means of the voice of RISE-UP participants, accounting for how the experience generated by the crossroads that the program creates between the professional interdisciplinarity, the approach to infrastructure’s sustainability, and the concept of resiliency, have impacted the experience of servingness for students in the program. 

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5. Building the Collaboration Graph of Open-Source Software Ecosystem

   https://doi.org/10.1109/MSR52588.2021.00086  

   Lyulina, Elena ; Jahanshahi, Mahmoud ( May 2021 , 2021 IEEE/ACM 18th International Conference on Mining Software Repositories (MSR))

   null (Ed.)

   The Open-Source Software community has become the center of attention for many researchers, who are investigating various aspects of collaboration in this extremely large ecosystem. Due to its size, it is difficult to grasp whether or not it has structure, and if so, what it may be. Our hackathon project aims to facilitate the understanding of the developer collaboration structure and relationships among projects based on the bi-graph of what projects developers contribute to by providing an interactive collaboration graph of this ecosystem, using the data obtained from World of Code [1] infrastructure. Our attempts to visualize the entirety of projects and developers were stymied by the inability of the layout and visualization tools to process the exceedingly large scale of the full graph. We used WoC to filter the nodes (developers and projects) and edges (developer contributions to a project) to reduce the scale of the graph that made it amenable to an interactive visualization and published the resulting visualizations. We plan to apply hierarchical approaches to be able to incorporate the entire data in the interactive visualizations and also to evaluate the utility of such visualizations for several tasks. 

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