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China Ocean Engineering 2024年第2期38卷 285-296页

作者： DU Zun-feng ZHU Hai-ming YU Jian-xing State Key Laboratory of Hydraulic Engineering Intelligent Construction and Operation School of Civil EngineeringTianjin UniversityTianjin 300350China

When investigating the vortex-induced vibration(VIV)of marine risers,extrapolating the dynamic response on the entire length based on limited sensor measurements is a crucial step in both laboratory experiments and fatigue monitoring of real *** problem is conventionally solved using the modal decomposition method,based on the principle that the response can be approximated by a weighted sum of limited vibration ***,the method is not valid when the problem is underdetermined,i.e.,the number of unknown mode weights is more than the number of known *** study proposed a sparse modal decomposition method based on the compressed sensing theory and the Compressive Sampling Matching Pursuit(Co Sa MP)algorithm,exploiting the sparsity of VIV in the modal *** the validation study based on high-order VIV experiment data,the proposed method successfully reconstructed the response using only seven acceleration measurements when the conventional methods failed.A primary advantage of the proposed method is that it offers a completely data-driven approach for the underdetermined VIV reconstruction problem,which is more favorable than existing model-dependent solutions for many practical applications such as riser structural health monitoring.

关键词： motion reconstruction vortex-induced vibration(VIV) marine riser modal decomposition method compressed sensing

Convolutional neural network adaptation and optimization method in SIMT computing mode

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The Journal of China Universities of Posts and Telecommunications 2024年第2期31卷 105-112页

作者： feng Zhenfu Zhang Yaying Yang Lele xing Lidong School of Electronic Engineering Xi'an University of Posts and TelecommunicationsXi'an 710121China

For studying and optimizing the performance of general-purpose computing on graphics processing units(GPGPU)based on single instruction multiple threads(SIMT)processor about the neural network application,this work contributes a self-developed SIMT processor named Pomelo and correlated assembly *** parallel mechanism of SIMT computing mode and self-developed Pomelo processor is briefly introduced.A common convolutional neural network(CNN)is built to verify the compatibility and functionality of the Pomelo *** computing flow with task level and hardware level optimization is adopted on the Pomelo processor.A specific algorithm for organizing a Z-shaped memory structure is developed,which addresses reducing memory access in mass data computing *** the above-combined adaptation and optimization strategy,the experimental result demonstrates that reducing memory access in SIMT computing mode plays a crucial role in improving performance.A 6.52.times performance is achieved on the 4 processing elements case.

关键词： parallel computing single instruction multiple threads(SIMT) convolutional neural network(CNN) memory optimization

Design and implementation of a multi-tile parallel scanning rasterization accelerator

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The Journal of China Universities of Posts and Telecommunications 2024年第2期31卷 94-104页

作者： xing Lidong Guo Qiang Peng Xinlong feng Zhenfu School of Electronic Engineering Xi'an University of Posts and TelecommunicationsXi'an 710121China

In the design of a graphic processing unit(GPU),the processing speed of triangle rasterization is an important factor that determines the performance of the *** architecture of a multi-tile parallel-scan rasterization accelerator was proposed in this *** accelerator uses a bounding box algorithm to improve scanning *** rasterizes multiple tiles in parallel and scans multiple lines at the same time within each *** highly parallel approach drastically improves the performance of *** the 65 nm process standard cell library of Semiconductor Manufacturing International Corporation(SMIC),the accelerator can be synthesized to a maximum clock frequency of 2.0 *** implementation on the Genesys2.field programmable gate array(FPGA)board fully verifies the functionality of the *** implementation shows a significant improvement in rendering speed and efficiency and proves its suitability for high-performance rasterization.

关键词： graphic processing unit(GPU) rasterization multi-tile parallelism

Cable coupling response in metal cavity under X-ray irradiation

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NUCLEAR SCIENCE AND TECHNIQUES 2024年第10期35卷 1-11页

作者： Zhang, Mao-xing Yuan, Lan-feng Meng, Cui Liu, Yi-Nong Tsinghua Univ Dept Engn Phys Beijing 100084 Peoples R China Minist Educ Lab Particle & Radiat Imaging Beijing 100084 Peoples R China Zhejiang Univ Coll Elect Engn Hangzhou 310007 Peoples R China

This study investigates the coupling response of cables inside a metal cavity under X-ray irradiation using the finite-difference time-domain method, particle simulation method, and transmission-line equation to solve the electromagnetic field inside the cavity and load voltage at the cable terminal under X-ray excitation. The results show that under a strong ionizing radiation environment of 1J/cm2\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${1}\,{\hbox {J/cm}{2}}$$\end{document}, a strong electromagnetic environment is generated inside the cavity. The cable shielding layer terminal couples a voltage of 15.32 V, whereas the core wire terminal couples a voltage of 0.31 V. Under strong X-ray irradiation, the metal cavity not only fails to provide electromagnetic shielding, but also introduces new electromagnetic interference. This study also provides a method for reducing the number of emitted electrons by adding low-Z materials, which can effectively reduce the coupled electric field and voltage.

关键词： Ionizing radiation Metal cavity System-generated electromagnetic pulse Transmission-line model SIMULATION CODE EQUATIONS IEMP

Hypoxia-mediated programmed cell death is involved in the formation of wooden breast in broilers

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Journal of Animal Science and Biotechnology 2024年第5期15卷 1918-1931页

作者： Xinrui Zhang Tong xing Lin Zhang Liang Zhao feng Gao College of Animal Science and Technology Key Laboratory of Animal Origin Food Production and Safety Guarantee of Jiangsu ProvinceJiangsu Collaborative Innovation Center of Meat Production and ProcessingQuality and Safety ControlNanjing Agricultural UniversityNo.1 WeigangNanjingJiangsu 210095P.R.China

Background Wooden breast(WB)myopathy is a common myopathy found in commercial broiler chickens *** examination has revealed that WB myopathy is accompanied by damage to the pectoralis major(PM)***,the underlying mechanisms responsible for the formation of WB in broilers have not been fully *** study aimed to investigate the potential role of hypoxia-mediated programmed cell death(PCD)in the formation of WB *** Histological examination and biochemical analysis were performed on the PM muscle of the control(CON)and WB groups.A significantly increased thickness of the breast muscle in the top,middle,and bottom portions(P2. and s O_(2. in the blood,were significantly decreased(P2. and TCO_(2. in the blood were significantly increased(P2.was significantly decreased(P<0.05)in the WB-affected PM muscle,indicating the occurrence of apoptosis mediated by the mitochondrial ***,the expressions of necroptosis-related factors RIP1,RIP3,and MLKL,as well as NF-κB and the pro-inflammatory cytokines TNF-α,IL-1β,and IL-6,were all significantly enhanced(P<0.05)in the WB-affected PM *** T

关键词： Apoptosis Autophagy Broiler chicken Hypoxia Necroptosis Wooden breast

Nitrogen-doped titanium dioxide/schwertmannite nanocomposites as heterogeneous photo-Fenton catalysts with enhanced efficiency for the degradation of bisphenol A

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Journal of Environmental Sciences 2024年第9期143卷 1-11页

作者： xing-xing Qiao Yu-Hang Xu Xiang-Ji Liu Sai-Le Chen Zhou Zhong Ya-{2. Li Jian Lü Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation College of Resources and EnvironmentFujian Agriculture and Forestry UniversityFuzhou 350002China State Key Laboratory of Photocatalysis on Energy and Environment Fuzhou UniversityFuzhou 350116China

Potential health risks related to environmental endocrine disruptors(EEDs)have aroused research hotspots at the forefront of water treatment ***,nitrogen-doped titanium dioxide/schwertmannite nanocomposites(N-TiO_(2./SCH)have been successfully developed as heterogeneous catalysts for the degradation of typical EEDs via photo-Fenton *** to the sustainable Fe(Ⅲ)/Fe(Ⅱ)conversion induced by photoelectrons,as-prepared N-TiO_(2./SCH nanocomposites exhibit much enhanced efficiency for the degradation of bisphenol A(BPA;ca.100% within 60 min under visible irradiation)in a wide pH range of 3.0-7.8,which is significantly higher than that of the pristine schwertmannite(ca.74.5%)or N-TiO_(2.(ca.10.8%).In this photo-Fenton system,the efficient degradation of BPA is mainly attributed to the oxidation by hydroxyl radical(·OH)and singlet oxygen(^(1)O_(2.).Moreover,the possible catalytic mechanisms and reaction pathway of BPA degradation are systematically investigated based on analytical and photoelectrochemical *** work not only provides a feasible means for the development of novel heterogeneous photo-Fenton catalysts,but also lays a theoretical foundation for the potential application of mineral-based materials in wastewater treatment.

关键词： Titanium dioxide Schwertmannite Fenton reaction Environmental endocrine disruptors Photocatalysis

The impacts of gradually terminating nonpharmaceutical interventions for SARS-CoV-2.A mathematical modelling analysis

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Fundamental Research 2024年第2期4卷 401-411页

作者： Bin Wu Yuetian Yu xing Lin feng Medical Decision and Economic Group Department of PharmacyRen Ji HospitalSouth CampusSchool of MedicineShanghai Jiaotong UniversityShanghai 200000China Department of Critical Care Medicine Ren Ji HospitalSchool of MedicineShanghai Jiaotong UniversityShanghai 200001China Department of Health Policy and Management School of Public HealthPeking UniversityBeijing 100191China

With the expansion of vaccination programs,the policy of terminating nonpharmaceutical interventions for preventing the SARS-CoV-2.pandemic should become more *** current study investigated the clinical and economic outcomes of intervention policies combining nonpharmaceutical interventions and vaccination programs for dealing with the SARS-CoV-2.*** agent-based transmission model was adopted that describes how a SARS-CoV-2.virus spreads in the populations of *** model inputs were derived from the literature and expert *** following intervention policies were simulated:no intervention,strict nonpharmaceutical interventions,and nonpharmaceutical interventions for workplace,community,school and home gradually terminated by combining vaccination programs for specified age groups(vaccination age in years:2.-60,2.-70,2.-80,≥2.,≥10 and whole population).Cumulative infections and deaths in one calendar year,costs and quality-adjusted life years(QALYs)were *** the vaccination program was taken up in at least the≥2. years age group in all populations,nonpharmaceutical interventions for workplace and community settings could be gradually terminated because the cumulative number of infections was<100 per 100,000 *** ending nonpharmaceutical interventions in school and home settings could not meet the target even when the vaccination program had been taken up in all *** cumulative deaths were used as the endpoint,nonpharmaceutical interventions in workplace,community and school settings could be gradually *** efficacy and coverage have substantial *** nonpharmaceutical interventions in workplace settings could produce the lowest cost when vaccination programs are taken up at least in the≥10 years age group;this method dominates most intervention strategies due to its lower costs and higher *** to our findings,nonpharmaceutical interventions might be gradually terminated

关键词： SARS-CoV-2 Nonpharmaceutical interventions Vaccination program Cumulative infections and deaths Economic outcomes

The Complete Classification of Graphs whose Second Largest Eigenvalue of the Eccentricity Matrix is Less Than 1

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Acta Mathematica Sinica,English Series 2024年第7期40卷 1741-1766页

作者： Jian feng WANG xing Yu LEI Shu Chao LI Zoran STANIC School of Mathematics and Statistics Shandong University of TechnologyZibo255049P.R.China Faculty of Mathematics and Statistics Central China Normal UniversityWuhan430079P.R.China Faculty of Mathematics University of BelgradeStudentski trg 1611000BelgradeSerbia

The eccentricity matrix of a graph is obtained from the distance matrix by keeping the entries that are largest in their row or column,and replacing the remaining entries by *** matrix can be interpreted as an opposite to the adjacency matrix,which is on the contrary obtained from the distance matrix by keeping only the entries equal to *** the paper,we determine graphs having the second largest eigenvalue of eccentricity matrix less than 1.

关键词： Eccentricity matrix eigenvalue diameter principal submatrix forbidden subgraph

High Permeability in Broadband of Co-sputtered [Fe-Fe_(2.)Ni_(80)/Cr]_(n) Multilayer Films

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Journal of Wuhan University of Technology(Materials Science) 2024年第2期39卷 410-416页

作者：罗创钰 LIU xing 王峰李维 State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China College of Materials and Chemical Engineering Hezhou UniversityHezhou 542899China

To achieve high microwave permeability in wide-band for the micron-thick magnetic films,[Fe-Fe_(2.)Ni_(80)/Cr]_(n) multilayer structure was proposed by co-sputtering Fe and FeNi to form the magnetic layers and Cr to form the *** multilayer structure contributes to the high permeability by reducing the coercivity and diminishing out-of-plane *** maximum imaginary permeability of[Fe-Fe_(2.)Ni_(80)/Cr]_(n) multilayer film reaches a large value of 800 at 0.52.GHz even though its overall thickness exceeds 1μ***,the magnetic resonance frequency of the multilayer film can be modulated from 0.52.to 1.35 GHz by adjusting the sputtering power of Fe from 0 to 86 W,and its bandwidth for μ’’>2.0(Δf) is as large as 2.0 *** desirable broad Δf of magnetic permeability,which can be well fitted by the Landau-Lifshitz-Gilbert equations,is due to dual magnetic resonances originated from double magnetic phases of Fe and FeNi that are of different saturation *** micron-thick multilayer films with high permeability in extended waveband are promising candidate for electromagnetic noise suppression application.

关键词： magnetron sputtering multiple magnetic resonance high permeability electromagnetic noise suppression

Optimized parameters of downhole all-metal PDM based on genetic algorithm

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Petroleum Science 2024年第4期21卷 2663-2676页

作者： Jia-xing Lu Ling-Rong Kong Yu Wang Chao feng Yu-Lin Gao China University of Geosciences (Beijing) Key Laboratory on Deep Geo-Drilling Technology of Ministry of Natural Resources

Currently, deep drilling operates under extreme conditions of high temperature and high pressure,demanding more from subterranean power motors. The all-metal positive displacement motor, known for its robust performance, is a critical choice for such drilling. The dimensions of the PDM are crucial for its performance output. To enhance this, optimization of the motor's profile using a genetic algorithm has been undertaken. The design process begins with the computation of the initial stator and rotor curves based on the equations for a screw cycloid. These curves are then refined using the least squares method for a precise fit. Following this, the PDM's mathematical model is optimized, and motor friction is assessed. The genetic algorithm process involves encoding variations and managing crossovers to optimize objective functions, including the isometric radius coefficient, eccentricity distance parameter,overflow area, and maximum slip speed. This optimization yields the ideal profile parameters that enhance the motor's output. Comparative analyses of the initial and optimized output characteristics were conducted, focusing on the effects of the isometric radius coefficient and overflow area on the motor's performance. Results indicate that the optimized motor's overflow area increased by 6.9%, while its rotational speed reduced by 6.58%. The torque, as tested by Infocus, saw substantial improvements of38.8%. This optimization provides a theoretical foundation for improving the output characteristics of allmetal PDMs and supports the ongoing development and research of PDM technology.

关键词： Positive displacement motor Genetic algorithm Profile optimization Matlab programming Overflow area