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1. Circuit Connection Reconfiguration of Partially Shaded BIPV Systems, a Solution for Power Loss Reduction

   Hosseiniirani, Seyedehhamideh; Kim, Kyoung-Hee (December 2023, ACSA Annual Meeting In Common)

   Integrating PV panels as a source of clean energy has been a widely established method to achieve net-zero energy (NZE) buildings. The exterior envelope of the high-rise buildings can serve as the best place to integrate PV panels for utilizing solar energy. The taller the building, the higher the potential to utilize solar energy by PV panels. However, shadows casting on the BIPV façade systems are unavoidable as they are often subject to partial shades from panels self-shading as well as building walls. Partial shading or ununiform solar radiation on the PV surface causes a dramatic decrease in the current output of the circuit. For that reason, in BIPV facades the default circuit connection of manufactured PV panels does not output maximum power under partial shading conditions. This paper investigates the different circuit connections in BIPV façade system to achieve higher energy yields while addressing design requirements. To this end, PV power production in different circuit connection reconfiguration scenarios was explored in two levels of BIPV components: 1) PV cells, and 2) strings of PV cells. Experimental tests conducted to validate the simulation results. The results of this study indicated that the maximum power generation occurred when the circuit connection between cells within a string is series, and the circuit connection between the strings within a PV panel is parallel. Results of the experimental tests shown that the series-parallel circuit connection increases the energy yields of the BIPV facades 71 times in real-world applications. The comparison analysis of the Ladybug energy simulations and the proposed analysis Grasshopper analysis recipe power output showed that the developed Grasshopper script will increase the BIPVs energy yields by 90% in simulations. 

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2. Analysis and Design of High-Efficiency Modular Multilevel Resonant DC-DC Converter

   https://doi.org/10.1109/OJPEL.2022.3215581  

   Li, Yanchao; Wei, Mengxuan; Lyu, Xiaofeng; Ni, Ze; Cao, Dong (January 2022, IEEE Open Journal of Power Electronics)

   This paper demonstrates a high-efficiency modular multilevel resonant DC-DC converter (MMRC) with zero-voltage switching (ZVS) capability. In order to minimize the conduction loss in the converter, optimizing the root-mean-square (RMS) current flowing through switching devices is considered an effective approach. The analysis of circuit configuration and operating principle show that the RMS value of the current flowing through switching devices is closely related to the factors such as the resonant tank parameters, switching frequency, converter output voltage and current, etc. A quantitative analysis that considers all these factors has been performed to evaluate the RMS current of all the components in the circuit. When the circuit parameters are carefully designed, the switch current waveform can be close to the square waveform, which has a low RMS value and results in low conduction loss. And a design example based on the theoretical analysis is presented to show the design procedures of the presented converter. A 600 W 48 V-to-12 V prototype is built with the parameters obtained from the design example section. Simulation and experiments have been performed to verify the high-efficiency feature of the designed converter. The measured converter peak efficiency reaches 99.55% when it operates at 200 kHz. And its power density can be as high as 795 W/in 3 . 

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3. The Marabou Framework for Verification and Analysis of Deep Neural Networks

   https://doi.org/10.1007/978-3-030-25540-4_26  

   Katz, Guy; Huang, Derek A; Ibeling, Duligur; Julian, Kyle; Lazarus, Christopher; Lim, Rachel; Shah, Parth; Thakoor, Shantanu; Wu, Haoze; Zeljić, Aleksandar; et al (July 2019, Lecture notes in computer science)

   Deep neural networks are revolutionizing the way complex systems are designed. Consequently, there is a pressing need for tools and techniques for network analysis and certification. To help in addressing that need, we present Marabou, a framework for verifying deep neural networks. Marabou is an SMT-based tool that can answer queries about a network’s properties by transforming these queries into constraint satisfaction problems. It can accommodate networks with different activation functions and topologies, and it performs high-level reasoning on the network that can curtail the search space and improve performance. It also supports parallel execution to further enhance scalability. Marabou accepts multiple input formats, including protocol buffer files generated by the popular TensorFlow framework for neural networks. We describe the system architecture and main components, evaluate the technique and discuss ongoing work. 

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4. Enhancing Adaptable Topological Wave Bandwidth in Piezoelectric Metamaterials via Circuitry and Lattice Symmetry Control

   https://doi.org/10.1115/SMASIS2020-2292  

   Dorin, Patrick; Wang, K. W. (September 2020, ASME 2020 Conference on Smart Materials, Adaptive Structures and Intelligent Systems)

   null (Ed.)

   Recently, an electromechanical metamaterial with integrated resonant circuit elements was developed that enables on-demand tailoring of the operating frequency and interface routes for topological wave transmission. However, limitations to the operating frequency region still exist, and a full exploration of the adaptive characteristics of the topological electromechanical metamaterial has yet to be undertaken. To advance the state of the art, this study investigates the ability to enhance the range of operating frequencies for topological wave transmission in a piezoelectric metamaterial by the reconfiguration of lattice symmetries and connection of negative capacitance circuitry. In addition, the capability to modify the interface mode localization is analyzed. The plane wave expansion method is utilized to define a working frequency region for protected topological wave transmission by evaluating a local topological charge. Numerical simulations verify the existence of topologically protected interface modes and illuminate how the localization and shape of these modes can be altered via external circuit parameters. Results show that the reconfiguration of the lattice structure and connection to negative capacitance circuity enhances the operating frequency bandwidth and interface mode localization control, greatly expanding the adaptive metamaterial capabilities. 

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5. From Network Administrator to Domain Scientist: Challenges with Creating Usable High Speed Networks

   Donovan, S.; Clark, R.; Bezerra, J. (October 2017, Internet2 Technology Exchange)

   It can take a domain scientist weeks to set up a circuit, meeting for hours with IT administrators to figure out exactly what is needed, approvals from their own campus along with the remote campuses to set up a simple circuit to transfer data between campuses on an ongoing basis. Talking about networks may as well be a foreign language to many domain scientists. As such, we need to make it easier for domain scientists to allocate and configure resources for scientific applications without needing to understand the details of bandwidth, circuits, and port numbers. This session will discuss the challenges in supporting domain science applications across long distances and multiple management domains. We will discuss the AtlanticWave/SDX project and how it approaches this problem, making it possible for a domain scientist with little networking know-how to create paths across an intercontinental network while making network administrators' lives easier in the process. We will focus on the tools being developed to manage the network, along with a practical demonstration spanning multiple SDN switches. 

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