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Journal of Modern Power Systems and Clean Energy 2024年第3期12卷 997-1002页

作者： Lei Chen Yong Min Liangshuai Hao Guangzheng xing Yalou Li Shiyun Xu Department of Electrical Engineering Tsinghua UniversityBeijing 100084China China Electric Power Research Institute Beijing 100192China

This letter studies large-disturbance stability of the power system with a synchronous generator(SG)and a converter-interfaced generation(CIG)connected to infinite *** power system is multi-timescale and first *** is shown that the boundary of region of attraction(ROA)of the simplified model is composed of stable manifolds of unstable equilibrium point(UEP)or semi-singular point(SSP),named anchor points,and singular surface *** type of anchor point determines the dominant instability pattern of the power *** the anchor point is UEP or SSP,the dominant instability pattern is the instability of rotor angle of SG or the instability of phase-locked loop and outer control loop(OCL)of CIG,*** of dominant instability pattern can be analyzed with the relative position relationship between UEP and *** effect of OCL is *** the OCL is activated,the ROA becomes smaller and the system is more prone to instability of *** is necessary to consider the OCL when studying the large-disturbance stability of the power system.

关键词： Converter-interfaced generation large-disturbance stability outer control loop phase-locked loop synchronous generator voltage source converter

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FG5绝对重力仪观测比对

测绘信息与工程 2008年第1期33卷 25-27页

作者：邢乐林刘冬至李建成李辉申重阳中国地震局地震研究所武汉大学测绘学院武汉市珞喻路129号430079

介绍了2006年绝对重力测量比对的概况,分析了观测和比对结果,探讨了高精度绝对重力测量在地壳垂直运动研究中的作用和应用前景。

关键词：比测绝对重力测量重力变化地震

Pulmonary Bacterial Infection and Liver Cirrhosis: Current Status and Treatment

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Infectious Microbes & Diseases 2024年第1期6卷 5-10页

作者： Yingying Zhao Song Yang Huichun xing Center of Liver Diseases Division 3 Beijing Ditan HospitalCapital Medical UniversityBeijingChina

Liver cirrhosis has a higher incidence rate and mortality when complicated with bacterial *** bacterial infections,especially bacterial pneumonia,increase the susceptibility of cirrhotic patients to decompensation,with a higher likelihood of *** pneu-monia is often overlooked in patients with liver cirrhosis,although it can impact the clinical progress and *** diagnosis and inappropriate antibiotic treatments are associated with poor prognosis and increased *** understanding of mechanisms and appropriate antibiotic treatments for cirrhosis-related bacterial pneumonia remain ***,we reviewed the epidemiology,clinical characteristics and treatment of pulmonary bacterial infections in cirrhotic patients to provide suggestions for clinical practice.

关键词： bacterial pneumonia liver cirrhosis epidemiology characteristics treatment

Transition from grain boundary migration to grain boundary sliding in magnesium bicrystals

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Acta Mechanica Sinica 2024年第8期40卷 17-31页

作者： Zheyuan xing Haidong Fan Chuanlong Xu Guozheng Kang School of Mechanics and Aerospace Engineering Southwest Jiaotong UniversityChengdu610031China Department of Mechanics Sichuan UniversityChengdu610065China

In polycrystalline magnesium(Mg)and Mg alloys,as the grain size decreases,the grain boundary(GB)mediated plasticity including GB sliding and GB migration becomes the dominant deformation *** this study,the motion of[1100]symmetric tilt GBs in Mg bicrystals is investigated using molecular dynamics(MD)*** effects of GB misorientation angle and temperature are *** low/room temperatures and varied GB misorientation angles in the range ofθ≥58.36°,the GB migration occurs via the shear coupling with the invariant plane of{0001};At 35.80°<θ<58.36°,both the GB migration and GB sliding happen and the invariant plane changes from{0001}plane to[1122]plane;At 26.54°≤θ≤35.80°,the GB migrates with the invariant plane of[1122];Finally,atθ<26.54°,the GB sliding becomes the main deformation *** 700 K,the GB sliding occurs at the misorientation angles in the range ofθ<58.36θ;while the GB migration occurs at the misorientation angles ofθ≥58.36°.By comparing the energy barriers of GB migration and GB sliding,it yields that the deformation mode with a low energy barrier always happens,which leads to the transition of deformation modes and agrees well with the MD simulation results.

关键词： Molecular dynamics simulations Magnesium Grain boundary migration Grain boundary sliding Temperature

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:20-60,20-70,20-80,≥20,≥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≥20 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

Embedded Majorana islands

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Science China(Physics,Mechanics & Astronomy) 2024年第9期67卷 154-164页

作者： Jin-xing Hou Alex Weststrom Rui Wang Wen-Li Yang Jian Li Institute of Modern Physics Northwest UniversityXi’an 710127China Department of Physics School of ScienceWestlake UniversityHangzhou 310030China Shaanxi Key Laboratory for Theoretical Physics Frontiers Xi’an 710127China Institute of Natural Sciences Westlake Institute for Advanced StudyHangzhou 310024China National Laboratory of Solid State Microstructures and Department of Physics Nanjing UniversityNanjing 210093China Collaborative Innovation Center for Advanced Microstructures Nanjing 210093China Peng Huanwu Center for Fundamental Theory Xi’an 710127China

Mesoscopic superconducting islands hosting Majorana zero modes(MZMs),or Majorana islands in short,offer a prototype of topological *** this work we investigate theoretically the model of a generic Majorana island tunneling-coupled to a singlepiece metallic substrate,hence an embedded Majorana *** show the crucial consequences of an interplay between the topological ground states nonlocally addressed by the MZMs and the metallic bath with coherent electron propagation:on the one hand,the topological degeneracy on the Majorana island can be preserved,by virtue of the particle-hole symmetry,despite the apparent bath-induced coupling between MZMs;on the other hand,the electronic interference in the metallic bath may lead to profound alterations to the renormalization group behavior of the hybrid system towards low energy/temperature compared with conventional Kondo *** work serves to establish the model of embedded Majorana islands as an experimentally relevant and theoretically intriguing problem particularly in the direction of topological quantum computation.

关键词： topological quantum computation Majorana zero modes topological qubit mesoscopic superconductor topological Kondo effect

Conjugate Vectors Method Applied to Asymmetrical Fault Analysis of Power Electronized Power Systems

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CSEE Journal of Power and Energy Systems 2024年第4期10卷 1536-1549页

作者： Yingbiao Li xing Liu Jiabing Hu Jianhang Zhu Jianbo Guo State Key Laboratory of Advanced Electromagnetic Technology(Huazhong University of Science and Technology) Wuhan 430074China China Electric Power Research Institute Beijing 100192China

With the wide application of power electronized resources(PERs),the amplitude and frequency of voltages show significant time-varying characteristics under asymmetrical *** a result,the traditional phasor model,impedance model,and symmetrical components method based on the constant amplitude and frequency of voltages are facing great ***,a novel asymmetrical fault analysis method based on conjugate vectors is proposed in this paper which can meet the modeling and analysis requirements of the network excited by voltages with time-varying amplitude/***,asymmetrical fault characteristics are *** an application,a faulted phase identification(FPI)strategy is proposed based on the fault *** correctness and superiority of the asymmetrical fault analysis method and FPI strategy are verified in time-domain simulations and a real-time digital simulator.

关键词： Asymmetrical fault characteristics conjugate vectors method dynamic asymmetrical fault analysis time-varying amplitude/frequency

Engineered interface of three-dimensional coralliform NiS/FeS_(2)heterostructures for robust electrocatalytic water cleavage

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Nano Research 2024年第6期17卷 4693-4701页

作者： Xin Yu Jing Mei Yeshuang Du Xiaohong Cheng xing Wang Qi Wu State Key Laboratory of New Textile Materials and Advanced Processing Technologies Wuhan Textile UniversityWuhan 430073China Hubei Key Laboratory of Pollutant Analysis&Reuse Technology College of Chemistry and Chemical EngineeringHubei Normal UniversityHuangshi 435002China Hubei Key Laboratory of Low Dimensional Optoelectronic Materials and Devices Hubei University of Arts and ScienceXiangyang 441053China

Heterojunction structures improve the intrinsic activity of electrocatalysts by enhancing the charge transfer between the catalyst and the *** this paper,the NiS/FeS_(2)heterostructured electrocatalyst is fabricated by a simple sulfidation method using an interface engineering strategy to adjust the surface electron density of the *** expected,NiS/FeS_(2)electrocatalyst exhibits superior activity and durable oxygen evolution reaction(OER)stability,requiring only a low overpotential of 183 mV to achieve a current density of 10 mA·cm^(−2)and can be stable for more than 80 h,superior to NiS,FeS_(2)electrocatalyst individually,and precious RuO_(2).Notably,NiS/FeS_(2)is also a good bifunctional electrocatalyst with good overall water splitting performance,and it only requires a voltage 1.56 V to obtain a current density of 10 mA·cm^(−2)for more than 12 ***,the NiS/FeS_(2)hybridization facilitates the formation of coral-like structures,increasing the electrochemical surface area(ECSA)and enhancing the charge transfer efficiency,thus leading to excellent electrocatalytic *** work proposes a constructive strategy for designing efficient electrocatalysts based on interface engineering,and lays a foundation for designing a new class of electrocatalysts.

关键词： NiS/FeS_(2) interface engineering nanorods bifunctional water splitting

CrossFormer Embedding DeepLabv3+ for Remote Sensing Images Semantic Segmentation

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Computers, Materials & Continua 2024年第4期79卷 1353-1375页

作者： Qixiang Tong Zhipeng Zhu Min Zhang Kerui Cao Haihua xing School of Information Science and Technology Hainan Normal UniversityHaikou571158China

High-resolution remote sensing image segmentation is a challenging task. In urban remote sensing, the presenceof occlusions and shadows often results in blurred or invisible object boundaries, thereby increasing the difficultyof segmentation. In this paper, an improved network with a cross-region self-attention mechanism for multi-scalefeatures based onDeepLabv3+is designed to address the difficulties of small object segmentation and blurred targetedge segmentation. First,we use CrossFormer as the backbone feature extraction network to achieve the interactionbetween large- and small-scale features, and establish self-attention associations between features at both large andsmall scales to capture global contextual feature information. Next, an improved atrous spatial pyramid poolingmodule is introduced to establish multi-scale feature maps with large- and small-scale feature associations, andattention vectors are added in the channel direction to enable adaptive adjustment of multi-scale channel *** proposed networkmodel is validated using the PotsdamandVaihingen datasets. The experimental results showthat, compared with existing techniques, the network model designed in this paper can extract and fuse multiscaleinformation, more clearly extract edge information and small-scale information, and segment boundariesmore smoothly. Experimental results on public datasets demonstrate the superiority of ourmethod compared withseveral state-of-the-art networks.

关键词： Semantic segmentation remote sensing multiscale self-attention

Flame Retardant Material Based on Cellulose Scaffold Mineralized by Calcium Carbonate

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Journal of Renewable Materials 2024年第1期12卷 89-102页

作者： Jinshuo Wang Lida xing Fulong Zhang Chuanfu Liu State Key Laboratory of Pulp and Paper Engineering School of Light Industry and EngineeringSouth China University of TechnologyGuangzhou510640China

Wood-based functional materials have developed *** the flammability significantly limits its further *** improve the flame retardancy,the balsa wood was delignified by NaClO2 solution to create a cellulose scaffold,and then alternately immersed in CaCl_(2) ethanol solution and NaHCO3 aqueous solution under *** high porosity and wettability resulting from delignification benefited the following mineralization process,changing the thermal properties of balsa wood *** organic-inorganic wood composite showed abundant CaCO_(3) spherical particles under scanning electron *** peak of the heat release rate of delignified balsa-CaCO_(3) was reduced by 33%compared to the native balsa,according to the cone calorimetric *** flame test demonstrated that the mineralized wood was flame retardant and ***,the mineralized wood also displayed lower thermal *** study developed a feasible way to fabricate a lightweight,fire-retardant,self-extinguishing,and heat-insulating wood composite,providing a promising route for the valuable application of cellulosic biomass.

关键词： Cellulose scaffold delignification CaCO_(3) mineralization fire retardancy