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arXiv 2024年

作者： Chung, Youngjoo Yang, Hyun Seok School of Electrical Engineering and Computer Science Gwangju Institute of Science and Technology Gwangju61005 Korea Republic of Department of Physics and Photon Science Gwangju Institute of Science and Technology Gwangju61005 Korea Republic of

We derive an exact formula F (e) which provides a concrete estimate for the total number and angular momentum of gravitons emitted during the nonrelativistic inspiral of two black holes. We show that the function F (e) is a slowly growing monotonic function of the eccentricity 0 ≤ e ≤ 1 and F (1) = 1.0128 · · · . We confirm and extend the results obtained by Page for the function F (e). We also get an exact result for the ratio (Formular presented) where the numerator 2~N (Li, ei) is the sum of the spin angular momentum magnitudes of the gravitons emitted and N (Li, ei) is the total number of gravitons emitted in the gravitational waves during nonrelativistic inspiral from an initial eccentricity ei down to a final eccentricity e = 0 and the denominator Li is the magnitude of the initial orbital angular momentum. If the orbit starts off with unit eccentricity ei = 1, we get the value ν(1) = 1.002 268 666 2 ± 10−10 which confirms the Page’s conjecture that the true value of ν(1) will lie between 1.001 · · · and 1.003 · · · . We also show that the formula F (e) for gravitons emitted, originally expressed as an infinite series, can be represented by a single function through an integral representation. © 2024, CC BY.

关键词： Black holes

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A Review on Partial Discharge Detection Techniques in High Voltage Rotating Machines

A Review on Partial Discharge Detection Techniques in High V...

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Annual Conference of Industrial Electronics Society

作者： Shady S. Refaat Mohammad AlShaikh Saleh Sayed Mohammad Kameli Department of Electrical and Computer Engineering Texas A&M University at Qatar Doha Qatar School of Physics Engineering and Computer Science University of Hertfordshire Hatfield United Kingdom Department of Electrical and Computer Engineering Texas A&M University College Station USA

ISBN: (数字)9781665464543

ISBN: (纸本)9781665464550

Monitoring partial discharges (PDs) in high voltage (HV) electrical equipment is an effective tool to prevent unscheduled shutdown and eliminate possible failures. The inception of PDs can take various forms within the insulation system and can be detected using established approaches. The most common cause of HV rotating machine failure is the initiation of PDs in the stator winding insulation system. Various online and offline techniques have been proposed to monitor, detect, diagnose, and locate PDs in HV rotating machines. This paper gives an overview of existing PD detection and localization technologies in HV rotating machines. A comparison of online and offline PD detection approaches is discussed in this paper. Finally, a brief review of the methods of PD classification is provided.

关键词： Partial discharges Location awareness Industrial electronics Insulation Reviews Rotating machines Energy dissipation Stator windings High-voltage techniques Monitoring

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Mathematical modeling of mixed convective MHD Falkner-Skan squeezed Sutterby multiphase flow with non-Fourier heat flux theory and porosity

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Applied Mathematics and Mechanics(English Edition) 2023年第11期44卷 2005-2018页

作者： Shuguang LI M.I.KHAN F.ALI S.S.ABDULLAEV S.SAADAOUI HABIBULLAH School of Computer Science and Technology Shandong Technology and Business UniversityYantai 264005Shandong ProvinceChina Department of Mechanics and Engineering Science Peking UniversityBeijing 100871China Department of Mechanical Engineering Lebanese American UniversityBeirut 11020Lebanon Department of Mathematical Sciences Federal Urdu University of ArtsSciences&TechnologyGulshan-e-IqbalKarachi 75300Pakistan Faculty of Chemical Engineering New Uzbekistan UniversityTashkent 100070Uzbekistan Department of Science and Innovation Tashkent State Pedagogical University named after NizamiTashkent 100070Uzbekistan Department of Physics Faculty of Science and ArtsMohayel AserKing Khalid UniversityAbha 61421Saudi Arabia State Key Laboratory of Turbulence and Complex System Collaborative Innovative Center for Advanced Aero-EnginesPeking UniversityBeijing 100871China

In a wide variety of mechanical and industrial applications,e.g.,space cooling,nuclear reactor cooling,medicinal utilizations(magnetic drug targeting),energy generation,and heat conduction in tissues,the heat transfer phenomenon is ***’s law of heat conduction has been used as the foundation for predicting the heat transfer behavior in a variety of real-world *** model’s production of a parabolic energy expression,which means that an initial disturbance would immediately affect the system under investigation,is one of its main ***,numerous researchers worked on such problem to resolve this *** last,this problem was resolved by Cattaneo by adding relaxation time for heat flux in Fourier’s law,which was defined as the time required to establish steady heat conduction once a temperature gradient is *** offered a material invariant version of Cattaneo’s model by taking into account the upper-connected derivative of the Oldroyd ***,both models are combinedly known as the Cattaneo-Christov(CC)*** this attempt,the mixed convective MHD Falkner-Skan Sutterby nanofluid flow is addressed towards a wedge surface in the presence of the variable external magnetic *** CC model is incorporated instead of Fourier’s law for the examination of heat transfer features in the energy expression.A two-phase nanofluid model is utilized for the implementation of *** nonlinear system of equations is tackled through the bvp4c technique in the MATLAB software *** influence of pertinent flow parameters is discussed and displayed through different *** and important results are summarized in the conclusion ***,in both cases of wall-through flow(i.e.,suction and injection effects),the porosity parameters increase the flow speed,and decrease the heat transport and the influence of drag forces.

关键词： sporosity Cattaneo-Christov(CC)heat flux model Falkner-Skan Sutterby nanofluid mixed convection stagnation point

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106 New Emission-line Galaxies and 29 New Galactic HⅡ Regions are Identified with Spectra in the Unknown Data Set of LAMOST DR7

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Research in Astronomy and Astrophysics 2022年第6期22卷 170-182页

作者： Yan Lu A-Li Luo Li-Li Wang You-Fen Wang Yin-Bi Li Jin-Shu Han Li Qin Yan-Ke Tang Bo Qiu Shuo Zhang Jian-Nan Zhang Yong-Heng Zhao CAS Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China College of Computer and Information Engineering&Institute for Astronomical Science Dezhou UniversityDezhou 253023China University of Chinese Academy of Science Beijing 100049China College of Physics and Electronic Information Dezhou UniversityDezhou 253023China School of Electronic Information Engineering Hebei University of TechnologyTianjin 300401China Department of Astronomy School of PhysicsPeking UniversityBeijing 100871China Kavli institute of Astronomy and Astrophysics Peking UniversityBeijing 100871China

This work is to retrieve emission-line spectra from the“Unknown”data set in LAMOST DR7 V1.2,most of which are low signal-to-noise ratios *** the work,we perform emission line search and redshift calculations on the Unknown data set to get possible emission line galaxy *** the galaxy spectra released by LAMOST as templates,the Product Quantization(PQ)based approximate nearest neighbor(ANN)search is used to retrieve the nearest neighbors of each *** keep the spectra for which the calculated redshift and the published redshift of the template meet the threshold,and 16,188 spectra with emission lines are obtained from the LAMOST DR7 Unknown data *** visual inspection of spectra 10,266 spectra are left,in which 5828 spectra are identified as emission-line galaxies,1782 spectra show ionization nebula features,and other 2656 are not clearly *** 5828 spectra,5720 can be found in Strasbourg astronomical Data Center catalog,Sloan Digital Sky Survey catalog,or NASA/IPAC Extragalactic Database *** 108 spectra(corresponding to 106unique coordinates of *** decl.)which have no record in these three databases are new discoveries;for the1782 spectra showing ionization nebula features,most of them have radial velocities less than 150 kilometers per *** check them with the latest version of WISE HⅡcatalog V2.0(short for HIICat V2)and 985 out of the1782 spectra belong to 72 HⅡ*** these HⅡregions,43 were previously identified while the other 29 are newly identified in this work including 797 newly observed ***,there are still 2656 spectra that cannot be clearly classified although they have obvious emission lines and with small ***,106 new emissionline galaxies and 29 new Galactic HⅡregions are identified,and we conclude that the ANN method sped up by the PQ algorithm is efficient in solving the problem of pairing spectra with massive data set to figure out their *** present our result

关键词： techniques spectroscopic-Galaxies-(ISM:)HⅡregions

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Improved YOLOv5s Algorithm for Target Detection in Highlighted Field Camera Surveillance Images

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Applied Mathematics and Nonlinear sciences 2024年第1期9卷

作者： Sun, Dan Liao, Zhiwu Zhou, Zhimin Zhang, Lei Wu, Wenfeng School of Computer Science and Technology Aba Teachers University Aba Sichuan 623002 China School of Computer Science Sichuan Normal University Sichuan Chengdu610101 China School of Resources and Environment Aba Teachers University Aba Sichuan 623002 China School of Physics and Electronic and Electrical Engineering Aba Teachers University Aba Sichuan 623002 China

The complex and changing environment in the field brings a more significant detection challenge to camera surveillance. This paper proposes target detection in camera surveillance images using the improved YOLOv5s algorithm for target tracking in surveillance images. Firstly, to address the weak feature extraction ability of YOLOv5s for small-scale and overlapping targets, the feature extraction performance of YOLOv5s is improved by combining the attention mechanism and substitution loss function in the deep learning network to improve the feature extraction performance of YOLOv5s for target detection in field camera surveillance images. Then, to test the improved algorithm’s performance, the improved algorithm in this paper is compared with SSD, Faster R-CNN, and YOLOv5s detection methods, and performance comparison experiments are done on the basis of the dataset. The results show that the average detection accuracy (MAP) of the algorithm in this paper is improved by 19%, 14.5% and 6.3% than SSD, Faster R-CNN, and YOLOv5s, respectively, and the average speed of detection is 324 FPS, the accuracy is improved, the detection is faster, and for the YOLOv5 m with DA and PT has a higher AP than the other models in this paper. This study enhances the scalability of YOLOv5s algorithm in complex environments, which is crucial for advancing image target detection. © 2023 Dan Sun, Zhiwu Liao, Zhimin Zhou, Lei Zhang and Wenfeng Wu, published by Sciendo.

关键词： Target tracking

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A Portable 3D-Printed Dielectric Lens Antennas for Liquid-Mixture Characterization

A Portable 3D-Printed Dielectric Lens Antennas for Liquid-Mi...

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2023 IEEE International Symposium on Antennas and Propagation, ISAP 2023

作者： Sangpet, Patchadaporn Thaiwirot, Wanwisa Chudpooti, Sukanya Akkaraekthalin, Prayoot Somjit, Nutapong Chudpooti, Nonchanutt Department of Electrical and Computer Engineering Faculty of Engineering King Mongkut’s University of Technology North Bangkok Bangkok Thailand Department of Industrial Physics and Medical Instrumentation Faculty of Applied Science King Mongkut’s University of Technology North Bangkok Bangkok Thailand School of Electronic and Electrical Engineering University of Leeds Leeds United Kingdom

ISBN: (纸本)9798350341140

The Fused Deposition Modeling (FDM) method is utilized in this research to present dielectric lens antennas that were 3D printed. The ultra-wideband (UWB) stub antenna's antenna characteristic is intended to be improved by the 3D-printed dielectric lens antennas. The proportion of ethanol in the liquid mixture sample is categorized using the transmission-line measuring technique. The device-under-test (DUT) is placed between two 3D-printed dielectric lens antennas. The glass bottle is filled with a 100-ml liquid sample and covered with a plastic cap. The 3D EM Simulation CST Studio is used to optimize the 10 mm gap between the dielectric lens antennas and the DUT. Six concentrations of the ethanol/water mixture, such as empty, 60%, 65%, 70%, and 80%, are measured to examine the measurement system. The measurement outcomes indicate the various S21 (transmission coefficient) levels between 9 GHz and 11 GHz. According to the trend of the suggested system, the level of the transmission coefficient, S21, will change downward when the proportion of ethanol is increased. Several better advantages, such as a nondestructive method, non-contact measurement, and support with a real-time monitoring system, are provided by the transmission-line measuring methodology using 3D-printed dielectric lens antennas. © 2023 IEEE.

关键词： 3D-printed dielectric lens antennas Fused Deposition Modeling technique non-destructive measurement real-time monitoring system

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The Controllability of Quantum Correlation under Geometry and Entropy Discords

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computers, Materials & Continua 2021年第3期66卷 3107-3120页

作者： Xiaoyu Li Yiming Huang Qinsheng Zhu Xusheng Liu Desheng Zheng School of Information and Software Engineering University of Electronic Science and Technology of ChinaChengdu610054China School of Physics University of Electronic Science and Technology of ChinaChengdu610054China Department of Chemistry and Biochemistry Utah State UniversityLoganUtah84322USA School of Computer Science Southwest Petroleum UniversityChengdu610000China

Quantum correlation plays a critical role in the maintenance of quantum information processing and nanometer device *** the past two decades,several quantitative methods had been proposed to study the quantum correlation of certain open quantum systems,including the geometry and entropy style discord ***,there are differences among these quantification methods,which promote a deep understanding of the quantum *** this paper,a novel time-dependent three environmental open system model is established to study the quantum *** system model interacts with two independent spin-environments(two spin-environments are connected to the other spin-environment)*** have calculated and compared the changing properties of the quantum correlation under three kinds of geometry and two entropy discords,especially for the freezing *** the same time,some original and novel changing behaviors of the quantum correlation under different timedependent parameters are studied,which is helpful to achieve the optimal revival of the quantum discord and the similar serrated form of the freezing ***,it shows the controllability of the freezing correlation and the robustness of these methods by adjusting time-dependent *** work provides a new way to control the quantum correlation and design nanospintronic devices.

关键词： Spin environment quantum correlation nanospintronic devices quantum information freezing phenomenon

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Sea-Land Segmentation of Remote Sensing Images Based on SDW-UNet

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computer Systems science & engineering 2023年第5期45卷 1033-1045页

作者： Tianyu Liu Pengyu Liu Xiaowei Jia Shanji Chen Ying Ma Qian Gao The Information Department Beijing University of TechnologyBeijing 100124China School of Physics and Electronic Information Engineering Qinghai Minzu UniversityXining810000China Advanced Information Network Beijing Laboratory Beijing100124China Computational Intelligence and Intelligent Systems Beijing key Laboratory Beijing100124China Department of Computer Science University of Pittsburgh15260USA

Image segmentation of sea-land remote sensing images is of great importance for downstream applications including shoreline extraction,the monitoring of near-shore marine environment,and near-shore target *** mitigate large number of parameters and improve the segmentation accuracy,we propose a new Squeeze-Depth-Wise UNet(SDW-UNet)deep learning model for sea-land remote sensing image *** proposed SDW-UNet model leverages the squeeze-excitation and depth-wise separable convolution to construct new convolution modules,which enhance the model capacity in combining multiple channels and reduces the model *** further explore the effect of position-encoded information in NLP(Natural Language Processing)domain on sea-land segmentation *** have conducted extensive experiments to compare the proposed network with the mainstream segmentation network in terms of accuracy,the number of parameters and the time cost for *** test results on remote sensing data sets of Guam,Okinawa,Taiwan China,San Diego,and Diego Garcia demonstrate the effectiveness of SDW-UNet in recognizing different types of sea-land areas with a smaller number of parameters,reduces prediction time cost and improves performance over other mainstream segmentation *** also show that the position encoding can further improve the accuracy of model segmentation.

关键词： Sea-land segmentation UNet depth-wise separable convolution squeeze-excitation position encoding

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SPONGE+: A NoC-based power gating scheme for overall router column opening and closing control

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Microelectronics Journal 2024年 149卷

作者： Ouyang, Yiming Chen, Zhiyuan Xu, Dongyu Liang, Huaguo School of Computer Science and Information Engineering Hefei University of Technology 485 Danxia Road Anhui Hefei230601 China School of Electronic Science and Applied Physics Hefei University of Technology 485 Danxia Road Anhui Hefei230601 China

Power gating, a general-purpose power saving technique, can be used to turn off inactive routers in Networks-on-Chip (NoCs) to reduce static power consumption. SPONGE is an advanced power gating scheme. When the router is dormant, SPONGE maintains the transmission of straight packets, which occupy a large percentage of the network, through a direct bypass design. At the same time, the energized router column's can ensure the normal transmission of turning packets. However, it suffers from increased latency due to excessive detours, aggravated load imbalance, and violation of the breakeven time (BET) constraint. To address the above problems, we propose an improved energy-efficient router architecture SPONGE+. First, we design a new router bypass architecture that enables powered-off routers to have the ability to transmit straight ahead and turn in the X-to-Y direction to reduce the bypass cost of packet transmission. Secondly, we propose a congestion-aware turning routing algorithm to balance the load among powered-on routers and improve network resource utilization. Finally, we pin improves the power gating mechanism for router columns to satisfy the BET constraint and further reduce the static power expenses. Experimental results indicate that, under real application scenarios, our scheme achieves a 27.3% reduction in static power consumption and a 10.5% decrease in packet latency compared to SPONGE, with commendable scalability. © 2024 Elsevier Ltd

关键词： Network-on-chip

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InSb-based THz Plasmonic Antenna for Dynamic Control of Radiative decay rate of Quantum emitters

InSb-based THz Plasmonic Antenna for Dynamic Control of Radi...

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2023 Photonics North, PN 2023

作者： Aghili, Sina Alaee, Rasoul Dolgaleva, Ksenia University of Ottawa School of Electrical Engineering and Computer Science OttawaONK1N 6N5 Canada University of Ottawa Department of Physics OttawaONK1N 6N5 Canada

ISBN: (纸本)9798350326734

We propose an InSb-based THz plasmonic antenna capable of dynamically tuning the radiative decay rate of an electric dipole emitter upon magnetization. The magnetized antenna supports magnetoplasmon modes that can radiatively couple to the transition dipole moment of the dipole source, resulting in multiband radiative decay rate enhancement. This proposed system holds great potential to realize tunable single photon sources with high saturation intensity in the THz regime. © 2023 IEEE.

关键词： III-V semiconductors

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