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IEEE International Conference on Plasma Science (ICOPS)

作者： L. P. Beving S. Baalrud M. Hopkins University of Michigan Applied Physics Program Ann Arbor Michigan United States of America Department of Nuclear Engineering and Radiological Sciences University of Michigan Ann Arbor Michigan United States of America Sandia National Laboratories Applied Optical and Plasma Sciences Albuquerque New Mexico United States of America

Electric fields are commonplace in plasmas and affect transport by driving currents and in some cases instabilities. Here, we use particle-in-cell simulations to demonstrate that an instability, named the electron-field instability, can be driven by a sufficiently weak $(\$ \vert\backslash \text{textrm} \{\mathrm{E}_{-}0\vert \backslash \text{lesssim} \mathrm{T}_\mathrm{e}/(\text{ellambda}_{-}\{\text{De}\})\$) \text{and large-scale} (\$\vert\backslash \text{textrm}\{\mathrm{E}\}_0/\text{nabla}\vert \text{textrm} \{\mathrm{E}\}_{-}0\vert\backslash\text{gtrsim}100\backslash\text{lambda}_{-}\{\text{De}\}\$)$ electric field. The instability has a wavelength of around 30 electron Debye lengths and has a growth-rate that is proportional to the electric field strength. The instability occurs from electrons accelerating above the Langmuir wave phase velocity at about 5 times the electron thermal velocity. Unlike other instabilities, the electron-field instability only requires that the electrons interact with the field and does not result from the relative drift between electron populations (a beam instability) or electrons and ions (the Buneman instability). In fact, the instability occurs near the electron plasma frequency which is much higher than both the beam or Buneman instabilities. The ubiquity of macroscopic electric fields in plasmas means the electron-field instability is possible in a host of systems ranging across low-temperature, space, and fusion plasmas. When comparing our simulations to linear theory we find that both agree until a non-linear state is reached in the simulations.

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What affects the performance of POD for the simulation of heat transfer through building component? 8

What affects the performance of POD for the simulation of he...

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8th International Building physics Conference, IBPC 2021

作者： Hou, Tianfeng Roels, Staf Janssen, Hans KU Leuven Department of Civil Engineering Building Physics Section Leuven3001 Belgium Data Assimilation Research Team RIKEN Center for Computational Science Kobe Japan RIKEN Prediction Science Laboratory Kobe Japan RIKEN Interdisciplinary Theoretical and Mathematical Sciences Program Kobe Japan

The capability of the proper orthogonal decomposition for the simulation of heat transfer in building components is investigated via three applications: linear heat transfer (not coupled to mass transfer), mildly non-linear heat transfer (coupled to air and moisture transfer (hygroscopic)) and highly non-linear heat transfer (coupled to moisture transfer (capillary)). It is shown that increasing non-linearity leads to an increasing number of required construction modes. To further investigate the reason for this degrading performance of POD, the singular values' decay progress from the different training snapshots is addressed in this paper. The results confirm that a fast decay of the singular values implies a high interrelation of the snapshots and a better performance of the POD method. © 2021 Institute of physics Publishing. All rights reserved.

关键词： Heat transfer

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The serotonergic psychedelic N,N-dipropyltryptamine alters information-processing dynamics in cortical neural circuits

arXiv

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arXiv 2023年

作者： Varley, Thomas F. Havert, Daniel Fosque, Leandro Alipour, Abolfazl Weerawongphrom, Naruepon Naganobori, Hiroki O'Shea, Lily Pope, Maria Beggs, John School of Informatics Computing & Engineering Indiana University BloomingtonIN United States Department of Psychological & Brain Sciences Indiana University BloomingtonIN United States Department of Physics Indiana University BloomingtonIN United States Program in Neuroscience Indiana University BloomingtonIN United States Indiana University BloomingtonIN United States

Most of the recent work in psychedelic neuroscience has been done using non-invasive neuroimaging, with data recorded from the brains of adult volunteers under the influence of a variety of drugs. While this data provides holistic insights into the effects of psychedelics on whole-brain dynamics, the effects of psychedelics on the meso-scale dynamics of cortical circuits remains much less explored. Here, we report the effects of the serotonergic psychedelic N,N-diproptyltryptamine (DPT) on information-processing dynamics in a sample of in vitro organotypic cultures made from rat cortical tissue. Three hours of spontaneous activity were recorded: an hour of pre-drug control, and hour of exposure to 10µM DPT solution, and a final hour of washout, once again under control conditions. We found that DPT reversibly alters information dynamics in multiple ways: first, the DPT condition was associated with higher entropy of spontaneous firing activity and reduced the amount of time information was stored in individual neurons. Second, DPT also reduced the reversibility of neural activity, increasing the entropy produced and suggesting a drive away from equilibrium. Third, DPT altered the structure of neuronal circuits, decreasing the overall information flow coming into each neuron, but increasing the number of weak connections, creating a dynamic that combines elements of integration and disintegration. Finally, DPT decreased the higher-order statistical synergy present in sets of three neurons. Collectively, these results paint a complex picture of how psychedelics regulate information processing in meso-scale cortical tissue. Implications for existing hypotheses of psychedelic action, such as the Entropic Brain Hypothesis, are discussed. © 2023, CC BY-NC-SA.

关键词： Neurons

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Rice Variety Identification Using Edge Feature Extraction and Texture-Based Segmentation

Rice Variety Identification Using Edge Feature Extraction an...

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International Seminar on Application for Technology of Information and Communication (ISemantic)

作者： Aji Setiawan Kusworo Adi Catur Edi Widodo Doctoral Program of Information Systems School of Postgraduate Studies Diponegoro University Semarang Indonesia Department of Information Technology Faculty of Engineering Darma Persada University Jakarta Indonesia School of Postgraduate Studies Diponegoro University Semarang Indonesia Department of Physics Faculty of Science and Mathematics Diponegoro University Semarang Indonesia

This research proposes a methodology for identifying the optimal feature combination using Support Vector Machine (SVM) based on edge and texture features. Canny, Sobel, and Prewitt for edge detection and GLCM, Gabor, and LBP for texture analysis are popular feature extraction techniques widely employed in various cases. The approach combines edge and texture features with SVM to classify rice types into five categories: Ipsala, Jasmine, Karacadag, Arborio, and Basmati. Experimental results demonstrate that SVM using Canny, Sobel, and Prewitt combined Gabor texture features outperforms the comparative methods. A comparative analysis based on accuracy scores using confusion matrices is conducted. Combining all feature edge methods, Canny, Sobel, and Prewitt with Gabor on SVM classification is the best model for rice object classification, achieving an accuracy of 96%.

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Large-Scale Multidisciplinary Design Optimization of an eVTOL Aircraft Using Comprehensive Analysis

Large-Scale Multidisciplinary Design Optimization of an eVTO...

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AIAA SciTech Forum and Exposition, 2023

作者： Sarojini, Darshan Ruh, Marius L. Sperry, Mark Yan, Jiayao Fletcher, Andrew Joshy, Anugrah Jo Scotzniovsky, Luca Ivanov, Alexander Orndorff, Nicholas Gandarillas, Victor Asher, Isaac Chambers, Jeff Gill, Hyunjune Lee, Seongkyu Cheng, Zeyu Rodriguez, Gabriel Zhao, Shuofeng Mi, Chunting Nascenzi, Thomas Cuatt, Timothy Winter, Tyler Guibert, Alexandre Cronk, Ashley Kim, Alicia Meng, Shirley Hwang, John T. Department of Mechanical and Aerospace Engineering University of California San Diego 9500 Gilman Dr La Jolla CA92093 United States Flight Physics Aurora Flight Sciences A Boeing Company 9950 Wakeman Drive ManassasVA20110 United States Engineering Department Aurora Flight Sciences A Boeing Company 9950 Wakeman Drive ManassasVA20110 United States Department of Mechanical and Aerospace Engineering University of California Davis 1 Shields Avenue DavisCA95616 United States Department of Electrical and Computer Engineering San Diego State University 5500 Campanile Dr San Diego92182 United States Research and Development M4 Engineering Inc 4020 Long Beach Blvd # 2 Long BeachCA90807 United States Structural Engineering Department University of California San Diego 9500 Gilman Dr La Jolla CA92093 United States Materials Science and Engineering Program University of California San Diego 9500 Gilman Dr La Jolla CA92093 United States Department of NanoEngineering University of California San Diego 9500 Gilman Dr La Jolla CA92093 United States

ISBN: (数字)9781624106996

ISBN: (纸本)9781624106996

This paper presents a framework under development for enabling large-scale multi-fidelity modeling and optimization of electric vertical takeoff and landing concepts (eVTOL). The key features of the framework are a geometry-centric approach to multidisciplinary design optimization (MDO), a modular functional-form representation of the disciplines involved in aircraft design, and fully automated derivative computations thereby allowing efficient gradient-based optimization. The framework is first presented in a general manner agnostic to the vehicle concept or the physics-based analyses used. The key disciplines involved in the design of eVTOL aircraft and the couplings between the disciplines are described. The framework is then applied to the design of the NASA lift-plus-cruise concept. Low-fidelity solvers of aerodynamics, propulsion, structural estimation, acoustics, powertrain, and battery are coupled together. The optimization considers 108 design variables and 16 constraints. It is shown that MDO considering geometric variables results in a design with lower gross mass than when the geometric variables are not considered. The optimization turnaround time of 30 minutes on a standard workstation demonstrates the capabilities of fully-coupled large-scale MDO using gradient-based optimization. The framework is under development and an open-source version will be released in the near future. © 2023, American Institute of Aeronautics and Astronautics Inc, AIAA. All rights reserved.

关键词： Geometry

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Depth-Dependent Photoluminescence Characteristic of Gesn/Sigesn Multi-Quantum Wells

SSRN

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SSRN 2022年

作者： Ojo, Solomon Stanchu, Hryhorii Acharya, Sudip Said, Abdulla Amoah, Sylvester Benamara, Mourad Li, Chen de Oliveira, Fernando M. Mazur, Yuriy I. Yu, Shui-Qing Salamo, Gregory J. Department of Electrical Engineering University of Arkansas FayettevilleAR72701 United States Material Science and Engineering Program University of Arkansas FayettevilleAR72701 United States Institute for Nanoscience and Engineering University of Arkansas FayettevilleAR72701 United States Department of Physics University of Arkansas FayettevilleAR72701 United States

Multi quantum wells (MQWs) structures based on (Si)GeSn hold promise for near- and mid-infrared light emission and photodetection applications on the Si platform. An MQW consisting of four GeSn/SiGeSn repetitions is grown by chemical vapor deposition (CVD) on Ge/Si(001) virtual substrate to study the interface quality and its effect on optical properties. Intermixing at GeSn/SiGeSn interfaces is found by secondary ion mass spectrometry, which is notably stronger at larger depths. The depth-dependent photoluminescence (PL) characteristic of the MQWs was performed by utilizing different excitation wavelengths and by tailoring the MQW thickness using H2O2-based etching. The results clearly indicate that PL emission is relatively weaker for the QWs with stronger intermixing. © 2022, The Authors. All rights reserved.

关键词： Chemical vapor deposition

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Experimental verification of the treatment of time-dependent flux in circuit quantization

arXiv

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arXiv 2022年

作者： Bryon, Jacob Weiss, D.K. You, Xinyuan Sussman, Sara Croot, Xanthe Huang, Ziwen Koch, Jens Houck, Andrew Department of Electrical Engineering Princeton University PrincetonNJ08540 United States Department of Physics and Astronomy Northwestern University EvanstonIL60208 United States Graduate Program in Applied Physics Northwestern University EvanstonIL60208 United States Department of Physics Princeton University PrincetonNJ08540 United States Center for Applied Physics and Superconducting Technologies Northwestern University EvanstonIL60208 United States

Recent theoretical work has highlighted that quantizing a superconducting circuit in the presence of time-dependent flux Φ(t) generally produces Hamiltonian terms proportional to dΦ/dt unless a special allocation of the flux across inductive terms is chosen. Here, we present an experiment probing the effects of a fast flux ramp applied to a heavy-fluxonium circuit. The experiment confirms that naïve omission of the dΦ/dt term leads to theoretical predictions inconsistent with experimental data. Experimental data are fully consistent with recent theory that includes the derivative term or equivalently uses "irrotational variables" that uniquely allocate the flux to properly eliminate the dΦ/dt term. Copyright © 2022, The Authors. All rights reserved.

关键词： Timing circuits

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Development of the Al2o3-B2o3-Sio2 Glass For Thermal Barrier Coating

SSRN

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SSRN 2023年

作者： Qiu, Jun-Yan Montecillo, Rhys Chen, Pin-Yi Tu, Chi-Shun Chen, Cheng-Sao Feng, Kuei-Chih International Ph.D. Program in Innovative Technology of Biomedical Engineering and Medical Devices Ming Chi University of Technology New Taipei City24301 Taiwan Department of Mechanical Engineering Ming Chi University of Technology New Taipei City24301 Taiwan Department of Physics Fu Jen Catholic University New Taipei City24205 Taiwan Department of Mechanical Engineering Hwa Hsia University of Technology New Taipei City23530 Taiwan

The glass coating is an important technique in the aerospace industry as a thermal insulation role to protect the inner layer to form a thermal protection system (TPS) at elevated temperature. The results show an increase of the glass transition temperature (from 650 °C to 750 °C) in B2O3-SiO2 systems with increasing SiO2 content and the devitrification of the α-cristobalite phase. The Al2O3 additive in B2O3-SiO2 glass can increase the glass transition temperature from 750 °C to 1000 °C, and also inhibit the α-cristobalite phase. The transformation from the unstable α-cristobalite phase to the amorphous phase occurs at specimen with 10 wt% Al2O3 addition. Microstructure characterization shows the flat morphology without cracks on the surface. This study demonstrates that the Al2O3- B2O3-SiO2 glass has a thermally stable behavior which can be used as an effective thermal barrier coating at elevated temperature. © 2023, The Authors. All rights reserved.

关键词： Silica

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Eco-Friendly High Entropy Oxide Rock-Salt Type Structure for Oxygen Evolution Reaction Obtained by Green Synthesis Using Red Seaweed (Rhodophyta)

SSRN

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SSRN 2024年

作者： Santos, Jakeline RAIANE DORA DOS Raimundo, Rafael A. de Oliveira, João F.G.A. Hortencio, Johnnys da S. Loureiro, Francisco J.A. Macedo, Daniel A. Morales, Marco A. Gualandi, Isacco Tonelli, Domenica Gomes, Uílame U. Materials Science and Engineering Postgraduate Program UFRN Natal59078-970 Brazil Department of Industrial Chemistry "Toso Montanari" Industrial Chemistry UNIBO V.le Risorgimento 4 Bologna40136 Italy Department of Theoretical and Experimental Physics Federal University of Rio Grande do Norte UFRN Natal59078-970 Brazil Gleb Wataghin Institute of Physics - R. Sérgio Buarque de Holanda 777 - Cidade Universitária Campinas13083-859 Brazil Department of Chemistry Federal University of Paraíba UFPB João Pessoa58.051-900 Brazil TEMA - Centre for Mechanical Technology and Automation Mechanical Engineering Department University of Aveiro 3810-193 Portugal LASI - Intelligent Systems Associate Laboratory Portugal Materials Science and Engineering Postgraduate Program Federal University of Paraíba UFPB João Pessoa58051-900 Brazil

Global energy consumption increases year after year, causing the depletion of non-renewable sources. According to the International Energy Agency (IEA), global demand for electrical energy is expected to increase by 3.3% in 2024. Therefore, developing new renewable sources is urgent, including new devices for energy storage and conversion, particularly those governed by electrochemical reactions. Water splitting is a clean and sustainable technology capable of facing this issue by producing oxygen and hydrogen from water and electricity. However, a problem related to this technology is the slow kinetics, making it necessary to develop new electrocatalysts with high electrochemical performance. To meet this requirement, this work deals with for the first time a high entropy oxide with rock-salt structure synthesized by a green solgel synthesis using red seaweed (Rhodophyta) as polymerizing agent. Solgel synthesis allows the large-scale production of nanomaterials with high uniformity and dispersion of the chemical elements involved. The literature, which discussed the production of these oxides, reveals that agents harmful to the environment are applied during the synthesis steps, including sodium hydroxide, acetic acid, hexadecyltrimethylammonium bromide, urea, and ammonia. The composition of the high entropy oxide is (Mg0.2 Ni0.2 Co0.2 Cu0.2 Zn0.2 )O, it displays a low overpotential (336 mV vs. RHE at 10 mA cm-2 ), Tafel slope of 68 mV dec-1 , and excellent durability. The electrochemical performance of the high entropy oxide prepared in this work is superior to other electrocatalysts of the same class that were produced using transition metal-based precursors. © 2024, The Authors. All rights reserved.

关键词： Entropy

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Video-Based Container Tracking System Using Deep Learning

Video-Based Container Tracking System Using Deep Learning

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International Conference on Cyber Physical, Computer and Automation Systems, CPCAS 2019

作者： Rahmat, Basuki Via, Yisti Vita Wasian, Abdullah Purbasari, Intan Yuniar Sari, Ni Ketut Wurjani, Widi Bandong, Steven Joelianto, Endra Siregar, Persaulian Faculty of Computer Science Universitas Pembangunan Nasional "Veteran" Jawa Timur Surabaya Indonesia Engineering Physics Doctoral Program Faculty of Industrial Technology Institut Teknologi Bandung Bandung Indonesia Instrumentation and Control Research Group Faculty of Industrial Technology Institut Teknologi Bandung Bandung Indonesia

ISBN: (纸本)9789813340619

The process of loading and unloading containers at the port is very important to be automated in order to increase productivity, revenues, efficiency and safety in the logistics transportation process especially in a maritime country like Indonesia. To achieve this, identification and tracking of container positions need to be done accurately so that container transfers can occur precisely and smoothly. In this study, YOLO deep learning is used to detect moving containers. The model is trained using container images, and then the validation and testing process are carried out on the model using other container images. The results of training are stored in several checkpoints which will be compared to get the most accurate model. Obtained YOLO gave good results for tracking containers with MAP value of 68.63% and LAMR of 0.31. © 2021, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.

关键词： Containers

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