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CSEE Journal of Power and Energy Systems 2024年第4期10卷 1664-1675页

作者： Feng Li qi Wang yi Tang Yan Xu Jie Dang School of Electrical Engineering Southeast UniversityNanjing 210000China center for Power Engineering(CPE) School of Electrical and Electronic EngineeringNanyang Technological UniversitySingapore 639798Singapore Central China Branch of State Grid Corporation of China Wuhan 430077China

Data-driven methods are widely recognized and generate conducive results for online transient stability ***,the tedious and time-consuming process of sample collection is often *** functioning of power systems involves repetitive sample collection due to the constant variations occurring in the operation mode,thereby highlighting the importance of collection *** a means to achieve high sample collection efficiency following the operation mode change,we propose a novel instance-transfer method based on compression and matching strategy,which facilitates the direct acquisition of useful previous samples,used for creating the new sample ***,we present a hybrid model to ensure rationality in the process of sample similarity comparison and selection,where features of analytical modeling with special significance are introduced into data-driven *** the same time,a data-driven method can also be integrated in the hybrid model to achieve rapid error correction of analytical models,enabling fast and accurate post-disturbance transient stability *** a paradigm,we consider a scheme for online critical clearing time estimation,where integrated extended equal area criterion and extreme learning machine are employed as analytical model part and data-driven error correction model part,*** results validate the credible efficacy of the proposed method.

关键词： Critical clearing time extreme learning machine instance-transfer method transient stability assessment

Liquid-metal microgrid stretchable electronics based on bionic leaf veins with ultra-stretchability and high conductivity

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Rare Metals 2024年第6期43卷 2747-2757页

作者： Xi-Di Sun Jun-Yang An yi-qi Sun Xin Guo Jing Wu Jiang-Bo Hua Meng-Rui Su yi Shi Li-Jia Pan Collaborative Innovation center of Advanced Microstructures School of Electronic Science and EngineeringNanjing UniversityNanjing 210093China

Stretchable electronics that monitor joint activity and treat diseases based on liquid metal could be used in the development of healthcare *** devices can be seamlessly integrated with human ***,most high-precision microstructures and complex patterns are difficult to fabricate due to the limitations of conventional fabrication solutions,resulting in suboptimal performance under practical ***,a liquid-metal stretchable system utilizing natural leaf veins was reported as microstructures,which was based on a biomimetic concept and utilized an all-solution process for the preparation of complex *** systems are ultra-high tensile(800%tensile strain),environmentally stable(20 days)and mechanically durable(300-cycle).The system can accurately recognize the wearer's finger bending level as well as simple gesture *** the same time,the system acts as a wearable heater,which can realize the fast heating behavior of heating up to 50℃in 3 min under the human body-safe voltage(1.5 V).The tensile stability is demonstrated by the heterogeneous integration of lasers(405 nm)with the system interconnects for a stretchable and wearable light source.

关键词： Stretchable electronics Liquid metal Stretchable conductor Vein Bionicist electronics

A virtual reference satellite differential method for relative correction of satellite ephemeris errors

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Science China(Physics,Mechanics & Astronomy) 2010年第12期53卷 2300-2306页

作者： CAI ChengLin 1,3 , LI XiaoHui 2,3 & WU HaiTao 2,3 1 Gulin University of Electronic Technology, 541004, China 2 national time service center, Chinese Academy of Sciences, Lintong 710600, China 3 Key Laboratory of Precision Navigation and Timing Technology, national time service center, Chinese Academy of Sciences, Lintong 710600, China 1. Gulin University of Electronic Technology Gulin 541004 China3. Key Laboratory of Precision Navigation and Timing Technology National Time Service Center Chinese Academy of Sciences Lintong 710600 China2. National Time Service Center Chinese Academy of Sciences Lintong 710600 China

In order to solve the problems that the novel wide area differential method on the satellite clock and ephemeris relative correction (CERC) in the non-geostationary orbit satellite constellation, a virtual reference satellite (VRS) differential principle using relative correction of satellite ephemeris errors is proposed. It is referred to be as the VRS differential principle, and the elaboration is focused on the construction of pseudo-range errors of VRS. Through qualitative analysis, it can be found that the impact of the satellite’s clock and ephemeris errors on positioning can basically be removed and the users’ positioning errors are near zero. Through simulation analysis of the differential performance, it is verified that the differential method is universal in all kinds of satellite navigation systems with geostationary orbit (GEO) constellation, Medium orbit (MEO) constellation or hybrid orbit constellation, and it has insensitivity to abnormal aspects of a satellite ephemeris and clock. Moreover, the real time positioning accuracy of differential users can be maintained within several decimeters after the pseudo-range measurement noise is effectively weakened or eliminated.

关键词： wide area differential method virtual reference satellite (VRS) satellite ephemeris errors satellite clock errors constellation

A study on volunteer augmentation navigation technology

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Science China(Physics,Mechanics & Astronomy) 2011年第6期54卷 1029-1034页

作者： WU HaiTao 1,2,LU XiaoChun 1,2,ZOU DeCai 1,2 & HAN Tao 1,2 1 national time service center,Chinese Academy of Sciences,Xi’an 710600,China 2 Key Laboratory of Precision Navigation and Timing Technology,Chinese Academy of Sciences,Xi’an 710600,China 1. national time service center Chinese Academy of Sciences Xi’an 710600 China2. Key Laboratory of Precision Navigation and Timing Technology Chinese Academy of Sciences Xi’an 710600 China

Navigation augmentation technology is one of the most common methods to increase the continuity,reliability and integrity of the global satellite navigation *** concept of volunteer augmentation navigation (VNA) is proposed and the elements and topological structure of VNA are also analyzed in this *** study focuses on the neural network model that volunteers and ordinary users use modern communication information network to exchange self-organizing *** neural cell model of Volunteer Augmentation Navigation using shared information is *** interactive general relative positioning is *** basic theories and methods of volunteer augmentation navigation are formed on the basis of the above-mentioned *** study of realization mechanism of volunteer augmentation technology helps to form a relatively integral architecture of volunteer augmentation navigation.A user self-service satellite navigation augmentation which combines information exchange and navigation services may strengthen the continuity,reliability and integrity of the navigation *** volunteer augmentation navigation theory proposed in this paper improves the traditional satellite navigation application model and expands the connotation and denotation of satellite navigation augmentation methods.

关键词： volunteer augmentation navigation self-organizing information exchange interactive general relative positioning

Enhancing thermoelectric performance in P-type Mg_(3)Sb_(2)-based Zintls through optimization of band gap structure and nanostructuring

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Journal of Materials Science & Technology 2024年第3期170卷 25-32页

作者： yi-bo Zhang Ji-Sheng Liang Chengyan Liu qi Zhou Zhe Xu Hong-bo Chen Fu-cong Li ying Peng Lei Miao Guangxi Key Laboratory of Information Material Engineering Research Center of Electronic Information Materials and DevicesMinistry of EducationSchool of Material Science and EngineeringGuilin University of Electronic TechnologyGuilin 541004China Guangxi Key Laboratory for Relativity Astrophysics Center on Nanoenergy ResearchGuangxi Key Laboratory of Processing for Nonferrous Metal and Featured MaterialsSchool of Physical Science&TechnologyGuangxi UniversityNanning 530004China Guangxi Key Laboratory of Precision Navigation Technology and Application Guilin University of Electronic TechnologySchool of Information and CommunicationGuilin 541004China

P-type Mg_(3)Sb_(2)-based Zintls have attracted considerable interest in the thermoelectric(TE)field due to their environmental friendliness and low ***,compared to their n-type counterparts,they show relatively low TE performance,limiting their application in TE *** this work,we simultaneously introduce Bi alloying at Sb sites and Ag doping at Mg sites into the Mg_(3)Sb_(2)to coopera-tively optimize the electrical and thermal properties for the first time,acquiring the highest ZT value of∼0.85 at 723 K and a high average ZT of 0.39 in the temperature range of 323-723 K in sample Mg_(2.94)Ag_(0.06)Sb_(1.9)Bi_(0.1).The first-principle calculations show that the codoping of Ag and Bi can shift the Fermi level into the valence band and narrow the band gap,resulting in the increased carrier concentration from 3.50×10^(17)cm^(-3)in the reference Mg 3 Sb 0.9 Bi 0.1 to∼7.88×10^(19)cm^(-3)in sample Mg 2.94 Ag 0.06 Sb 0.9 Bi *** a result,a remarkable power factor of∼778.9μW m^(-1)K^(-2)at 723 K is achieved in sample Mg 2.94 Ag 0.06 Sb 0.9 Bi ***,a low lattice thermal conductivity of∼0.48 W m^(-1)K^(-1)at 723 K is also obtained with the help of phonon scattering at the distorted lattice,point defects,and nano-precipitates in sample Mg 2.94 Ag 0.06 Sb 0.9 Bi *** synergistic effect of using the multi-element co-doping/-alloying to optimize electrical properties in Mg_(3)Sb_(2)holds promise for further improving the TE performance of Zintl phase materials or even others.

关键词： Thermoelectric materials Band engineering Nanostructuring P-type Mg_(3)Sb_(2) Ag and Bi Co-doping

An analysis of the wide area differential method of geostationary orbit satellites

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Science China(Physics,Mechanics & Astronomy) 2009年第2期52卷 310-314页

作者： CAI ChengLin1,2,3?, LI XiaoHui1 & WU HaiTao1 1 national time service center, Chinese Academy of Sciences, Lintong 710600, China 2 Hunan Institute of Humanities, Science and Technology, Loudi 417000, China 3 Graduate University of Chinese Academy of Sciences, Beijing 100049, China 1. national time service center Chinese Academy of Sciences Lintong 710600 China 2. Hunan Institute of Humanities Science and Technology Loudi 417000 China 3. Graduate University of Chinese Academy of Sciences Beijing 100049 China

This work aims to obtain a wide area differential method for geostationary orbit (GEO) constellation. A comparison between the dilution of precision (DOP) of four-dimensional (4D) calculation including sa- tellite clock errors and ephemeris errors and that of three-dimensional (3D) calculation only including ephemeris errors with the inverse positioning theory of GPS shows the conclusion that all the 3D PDOPs are greatly reduced. Based on this, a basic idea of correcting satellite clock errors and ephem- eris errors apart is put forward, and moreover, a specific method of separation is proposed. Satellite clock errors are separated in a master station with time synchronization, and all the remaining pseu- do-range errors after the satellite clock errors have been deducted are used to work out ephemeris corrections of all GEO satellites. By a comparative analysis of user positioning accuracy before and after differential, the wide area differential method is verified to be quite valid for GEO constellation.

关键词： geostationary orbitsatellite dilution of precision satellite ephemeris errors satellite clock errors wide area differential method

Astronomical function and date of the Taosi observatory

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Science China(Physics,Mechanics & Astronomy) 2009年第1期52卷 151-158页

作者： WU JiaBi1, CHEN MeiDong2 & LIU CiYuan3 1 national Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012, China 2 Institute for the History of Natural Science, Chinese Academy of Sciences, Beijing 100010, China 3 national time service center, Chinese Academy of Sciences, Xi’an 710600, China 1. national Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China 2. Institute for the History of Natural Science Chinese Academy of Sciences Beijing 100010 China 3. national time service center Chinese Academy of Sciences Xi’an 710600 China

The Taosi site in Xiangfen County,Shanxi Province,may be the capital of the King Yao. Archeologists recently discovered a large semi-circular stamped-earth platform, II FJT1,which has a clear and definite pounded-earth central core together with a curved wall perforated by twelve gaps. The platform is said to be an ancient observatory used to determine the seasons by watching the sunrise. Each feature of II FJT1 was precisely measured and the data are reproduced in this paper. An astronomical analysis of slots E2 and E12 was carried out using the azimuths of the slots' centerlines and the vertical angle of the mountain ridge opposite, above which the sun rises. The results show that at present the sun is close to the two slots but does not exactly enter them at summer and winter solstice sunrise. Using 14C analysis archeologists dated the site to about 2100 BC. Because of the secular change in the obliquity of the ecliptic,at that date on the summer solstice the half-risen sun would have appeared inside slot E12 just to the right of the centerline,and on the winter solstice the sun would have been exactly on the centerline of slot E2. This result provides compelling proof that II FJT1 is an ancient observatory.

关键词： astro-archeology astro-chronology Taosi culture ancient observatory time service

MOF and its derivative materials modified lithium-sulfur battery separator:a new means to improve performance

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Rare Metals 2024年第6期43卷 2418-2443页

作者： Rong-Wei Huang Yong-qi Wang Dan You Wen-Hao Yang Bin-Nan Deng Fei Wang Yue-Jin Zeng yi-Yong Zhang Xue Li national Local Joint Engineering Research center for Lithium-Ion Batteries and Materials Preparation Technology Key Laboratory of Advanced Batteries Materials of Yunnan ProvinceFaculty of Metallurgical and Energy EngineeringKunming University of Science and TechnologyKunming 650093China State Key Laboratory of Physical Chemistry of Solid Surfaces Collaborative Innovation Centre of Chemistry for Energy MaterialsState-Province Joint Engineering Laboratory of Power Source Technology for New Energy VehicleEngineering Research Center of Electrochemical TechnologyMinistry of EducationCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China

In recent years,lithium-sulfur batteries(LSBs)are considered as one of the most promising new generation energies with the advantages of high theoretical speeific capacity of sulfur(1675 mAh·g^(-1)),abundant sulfur resources,and environmental friendliness storage technologies,and they are receiving wide attention from the ***,the problems of the shuttle effect and lithium dendrite growth in LSBs have limited their practical application,so there is a need to find ways to solve these *** is an excellent choice to use novel materials to modify battery *** those novel materials,the metal-organic framework(MOF)has the properties of regular pores and controllable *** applied as a positive electrode and diaphragm,it can restrain the shuttle effect and lithium dendrite growth,especially since it shows excellent performance in diaphragm ***,various design strategies and synthesis methods of MOF-modified separators are reviewed in this paper,and the applications of MOF in LSBs separators in different forms are introduced,including the composite of MOF and carbon-based materials,the compounding of MOF and polymer,self-carbonization to form MOF-derived *** the same time,different characterization techniques are systematically reviewed to obtain the physical and chemical properties of MOF particles and the working mechanism of MOF-modified diaphragm,which provides a basis for further research in this ***,some future research trends and directions are put forward to fully tap the future commercial potential of MOF-modified diaphragm in LSBs.

关键词： MOF Lithium-sulfur battery Modified diaphragms Design strategies Prospect Characterization

Optimization of tracheoesophageal fistula model established with Tshaped magnet system based on magnetic compression technique

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World Journal of Gastroenterology 2024年第16期30卷 2272-2280页

作者： Miao-Miao Zhang Jian-qi Mao Lin-Xin Shen Ai-Hua Shi Xin Lyu Jia Ma yi Lyu Xiao-Peng Yan Department of Hepatobiliary Surgery The First Affiliated Hospital of Xi’an Jiaotong UniversityXi’an 710061Shaanxi ProvinceChina Shaanxi Provincial Key Laboratory of Magnetic Medicine The First Affiliated Hospital of Xi’an Jiaotong UniversityXi’an 710061Shaanxi ProvinceChina Zonglian College Xi’an Jiaotong UniversityXi’an 710061Shaanxi ProvinceChina national Local Joint Engineering Research center for Precision Surgery&Regenerative Medicine The First Affiliated Hospital of Xi’an Jiaotong UniversityXi’an 710061Shaanxi ProvinceChina Department of Pulmonary and Critical Care Medicine The Second Affiliated Hospital of Xi’an Jiaotong UniversityXi’an 710004Shaanxi ProvinceChina Department of Surgical Oncology Shaanxi Provincial People’s HospitalXi’an 710068Shaanxi ProvinceChina

BACKGROUND The magnetic compression technique has been used to establish an animal model of tracheoesophageal fistula(TEF),but the commonly shaped magnets present limitations of poor homogeneity of TEF and poor model *** designed a Tshaped magnet system to overcome these problems and verified its effectiveness via animal *** To investigate the effectiveness of a T-shaped magnet system for establishing a TEF model in beagle *** Twelve beagles were randomly assigned to groups in which magnets of the Tshaped scheme(study group,n=6)or normal magnets(control group,n=6)were implanted into the trachea and esophagus separately under *** time,operation success rate,and accidental injury were *** operation,the presence and timing of cough and the time of magnet shedding were *** in the control group were euthanized after X-ray and gastroscopy to confirm establishment of TEFs after coughing,and gross specimens of TEFs were *** in the study group were euthanized after X-ray and gastroscopy 2 wk after surgery,and gross specimens were *** size was measured in all animals,and then harvested fistula specimens were examined by hematoxylin and eosin(HE)and Masson trichrome *** The operation success rate was 100%for both *** time did not differ between the study group(5.25 min±1.29 min)and the control group(4.75 min±1.70 min;P=0.331).No bleeding,perforation,or unplanned magnet attraction occurred in any animal during the *** the early postoperative period,all dogs ate freely and were generally in good *** in the control group had severe cough after drinking water at 6-9 d after surgery.X-ray indicated that the magnets had entered the stomach,and gastroscopy showed TEF *** specimens of TEFs from the control group showed the formation of fistulas with a diameter of 4.94 mm±1.29 mm(range,3.52-6.56 mm).HE and Masson trichrome staining showed s

关键词： Magnetic surgery Magnetic compression technique Tracheoesophageal fistula Magnet Animal model Beagles