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High Voltage 2022年第3期7卷 483-495页

作者： Bin Xiang Wenqing wang Hongxu Li Lei Gao Zhiyuan Liu Yingsan Geng jianhua wang Youping Tu Department of Electrical Engineering State Key Laboratory of Electrical Insulation and Power EquipmentXi'an Jiaotong UniversityXi'anChina State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power UniversityBeijingChina

Superconducting fault current limiters(SFCLs)are important in improving the stability of electrical power ***,the existing resistive-type DC SFCL has a long re-covery time,which cannot meet the requirements of power system ***,it is necessary to investigate the methods of reducing recovery time of *** the simulations on superconducting tapes,there is a lack of investigation about the effects of design factors of superconducting tapes and coils such as material,thickness,coil radius,coil winding method on recovery *** objective of this study is to obtain the effects of material and geometric properties of superconducting tapes and coils on recovery characteristics and obtain methods to reduce the recovery *** recovery times under different conducting currents are also compared by simulations and exper-iments to verify simulation *** maximum error is below 40%and most of the cases have an error below 10%.Besides,by increasing tape thickness,the recovery time can be reduced by 22%.Tape materials and coil winding methods can be designed ac-cording to the auto-reclosure and current-limiting requirements of the power *** research provided directions for the design of superconducting tape and super-conducting coil for resistive-type DC SFCLs.

关键词： fault winding conducting

Characterization of the retinal vasculature in fundus photos using the PanOptic iExaminer system

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Eye and Vision 2020年第2期7卷 444-453页

作者： Huiling Hu Haicheng Wei Mingxia Xiao Liqiong Jiang Huijuan wang Hong Jiang Tatjana Rundek jianhua wang Shenzhen Key Laboratory of Ophthalmology Shenzhen Eye HospitalJinan UniversityShenzhenChina Department of Ophthalmology Bascom Palmer Eye InstituteUniversity of Miami Miller School of Medicine1638 NW 10th AvenueMcKnight Building-Room 202AMiamiFL 33136USA Department of Electrical and Computer Engineering Florida International UniversityMiamiFLUSA School of Electrical and Information Engineering North Minzu UniversityYinchuanNingxiaChina Eye hospital China Academy of Chinese Medical SciencesBeijingChina Department of Neurology University of Miami Miller School of MedicineMiamiFLUSA

Background:The goal was to characterize retinal vasculature by quantitative analysis of arteriole-to-venule(A/V)ratio and vessel density in fundus photos taken with the PanOptic iExaminer ***:The PanOptic ophthalmoscope equipped with a smartphone was used to acquire fundus photos centered on the optic nerve *** fundus photos of a total of 19 eyes from 10 subjects were *** vessels were analyzed to obtain the A/V *** addition,the vessel tree was extracted using deep learning U-NET,and vessel density was processed by the percentage of pixels within vessels over the entire ***:All images were successfully processed for the A/V ratio and vessel *** was no significant difference of averaged A/V ratio between the first(0.77±0.09)and second(0.77±0.10)measurements(P=0.53).There was no significant difference of averaged vessel density(%)between the first(6.11±1.39)and second(6.12±1.40)measurements(P=0.85).Conclusions:Quantitative analysis of the retinal vasculature was feasible in fundus photos taken using the PanOptic *** device appears to provide sufficient image quality for analyzing A/V ratio and vessel density with the benefit of portability,easy data transferring,and low cost of the device,which could be used for pre-clinical screening of systemic,cerebral and ocular diseases.

关键词： Smartphone ophthalmoscope Image analysis Deep learning Arteriovenous ratio Vessel density Retina

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Optical coherence tomography for ocular surface and corneal diseases: a review

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Eye and Vision 2018年第1期5卷 126-136页

作者： Nandini Venkateswaran Anat Galor jianhua wang Carol L.Karp Bascom Palmer Eye Institute University of Miami Miller School of MedicineMcKnight Building Room 202A1638 NW 10th Avenue900 NW 17th StreetMiamiFL 33136USA Department of Ophthalmology Miami Veterans Administration Medical Center1201 NW 16th StreetMiamiFL 33125USA

The advent of optical coherence tomography(OCT)imaging has changed the way ophthalmologists image the ocular surface and anterior segment of the *** ability to obtain dynamic,high and ultra-high resolution,cross-sectional images of the ocular surface and anterior segment in a noninvasive and rapid manner allows for ease of *** this review,we focus on the use of anterior segment OCT,which provides an“optical biopsy”or in vivo imaging of various ocular surface and corneal pathologies,allowing the clinician to diagnose diseases otherwise not visualized by traditional *** utility of anterior segment OCT for various anterior segment pathologies is reviewed.

关键词： Anterior segment optical coherence tomography Ocular surface imaging Ocular surface lesions

Exploring best‑matched embedding model and classifier for charging‑pile fault diagnosis

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Cybersecurity 2023年第3期6卷 85-97页

作者： Wen wang jianhua wang Xiaofeng Peng Ye Yang Chun Xiao Shuai Yang Mingcai wang Lingfei wang Lin Li Xiaolin Chang State Grid Electric Vehicle Service Company Ltd.1 Baiguang RoadXicheng DistrictBeijingChina State Grid Shanxi Marketing Service Center 10 Wuluo StreetTanghuai GardenTaiyuanShanxiChina Beijing Key Laboratory of Security and Privacy in Intelligent Transportation Beijing Jiaotong University3 ShangyuancunBeijing 100044China

The continuous increase of electric vehicles is being facilitating the large-scale distributed charging-pile *** is crucial to guarantee normal operation of charging piles,resulting in the importance of diagnosing charging-pile *** existing fault-diagnosis approaches were based on physical fault data like mechanical log data and sensor data ***,there are other types of fault data,which cannot be used for diagnosis by these existing *** paper aims to fill this gap and consider 8 types of fault data for diagnosing,at least including physical installation error fault,charging-pile mechanical fault,charging-pile program fault,user personal fault,signal fault(offline),pile compatibility fault,charging platform fault,and other *** aim to find out how to combine existing feature-extraction and machine learning techniques to make the better diagnosis by conducting experiments on realistic dataset.4 word embedding models are investigated for feature extraction of fault data,including N-gram,GloVe,Word2vec,and ***,we classify the word embedding results using 10 machine learning classifiers,including Random Forest(RF),Support Vector Machine,K-Nearest Neighbor,Multilayer Perceptron,Recurrent Neural Network,AdaBoost,Gradient Boosted Decision Tree,Decision Tree,Extra Tree,and *** with original fault record dataset,we utilize paraphrasing-based data augmentation method to improve the classification accuracy up to 10.40%.Our extensive experiment results reveal that RF classifier combining the GloVe embedding model achieves the best accuracy with acceptable training *** addition,we discuss the interpretability of RF and GloVe.

关键词： Charging-pile Fault diagnosis Machine learning classifier Word embedding

Mathematical Foundation of Visual Query Languageon Spatial Information

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Journal of Systems Engineering and Electronics 2000年第4期11卷 66-72页

作者： wang jianhua Guo Jingjun Yan Huiwu Zhu Guorui Wu Hehai Department of Civil Engineering Tsinghua UniversityBeijing 100084 P. R. China Department of Civil Engineering Tsinghua UniversityBeijing 100084 P. R. China

Visual Query Language on Spatial Information (SIVQL) is one kind of visual query language based on the extension of Query by Example (QBE). It is a visual operation based on graphics or media object, such as point, line and area elements. In this paper, the relation calculation and query function of SIVQL have been studied and discussed by using set theory and relation algebra. The theory foundation of SIVQL has been investigated by the mathematical method. Finally, its application examples are also given with the specific information system.

关键词： Visual query language Relation algebra Mathematical foundation

Embedded integrated servo-controllers for intelligent modular actuators

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High Technology Letters 2006年第1期12卷 37-41页

作者：陈伟海 Yu Shouqian wang jianhua Kou Jinqiao School of Automation Beijing University of Aeronautics and Astronautics Beijing 100083 P.R. China

This paper focuses on the development of an embedded integrated servo-controller （EISC） for servomotors. Comprising of mainly servo-controller and servo-amplifiers, this EISC is capable of controlling a wide range of servomotors to perform complieated tasks. Hence, integration of this EISC with a servomotor forms an intelligent modular actuator （IMA） that is essential to modern manufacturing industries. The development of such an EISC involves two major tasks： first, designing the hardware of a compact-sized and highly compatible EISC, and second, developing the software functions to facilitate its functionalities and capahilities. The developed EISC hence forms an integrated-servo-eontrol module, which determines the capability, functionality, flexibility and responsiveness of these IMAs.

关键词： modular actuatorembedded integrated controller intelligent actuator modular actuatorem

Numerical simulations of land surface physical processes and land-atmosphere interactions over oasis-desert/Gobi region

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Science China Earth Sciences 2007年第2期50卷 290-295页

作者： LIU ShuHua LIU HePing HU Yu ZHANG ChengYi LIANG FuMing wang jianhua Department of Atmospheric Sciences School of PhysicsPeking UniversityBeijing 100871China Laboratory of Climate Research National Climatic CenterChina Meteorological AdministrationBeijing 100081China

A land-surface physical process model was coupled with a mesoscale atmospheric model. This cou- pled model was then used to simulate the interactions between land and the atmosphere, including surface temperature, net radiation, sensible heat flux and latent heat flux over a desert/Gobi with an oasis in northwestern semiarid regions in China. Comparisons between observations and simulations were made over the oasis and the desert/Gobi, respectively. Both cold island effect and wet island ef- fect, the so-called oasis effect, were observed and simulated. Lower temperature, higher specific hu- midity and weaker turbulent transfer were present over the oasis than the desert/Gobi. A subsidence occurred over the oasis, leading to a thermally-generated mesoscale circulation.

关键词： desert/Gobi and oasis land surface physical process land-atmosphere interactions oasis effect numerical simulation

ANALYSIS OF COOLING CHARACTERISTICS IN UNDERWATER WELDING BY FINITE ELEMENT METHOD

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China Ocean Engineering 1987年第2期1卷 94-100页

作者： Chen Chu, wang jianhua Yang Hongqing (Shanghai Jiaotong University, Shanghai) Shanghai Jiaotong Univ Shanghai China Shanghai Jiaotong Univ Shanghai China

In this paper, non-linear welding temperature fields are analyzed by finite element method. A mathematical model is proposed to calculate the temperature fields of local drying underwater welding. As an example, the temperature field of local drying underwater welding for 6 mm thick steel sheet is calculated. A comparison is made among the effects of various welding conditions on cooling characteristics in fusion zone. The cooling speed from 800 ℃ to 500 ℃ can be decreased with the increase of shield radius, the coordination of low heat input with low welding speed or the reduction of heat conduction at the bottom, thus improving the quality of welding joints. It has been shown that the finite element method, as a useful tool for analysing heat transfer of underwater welding under various conditions, can be employed to provide a basis for the analysis of material’s underwater weldability, the design of proper underwater welding equipment and the rational selection of welding parameters.

关键词： ANALYSIS OF COOLING CHARACTERISTICS IN UNDERWATER WELDING BY FINITE ELEMENT METHOD heat

Improving diabetic and hypertensive retinopathy with a medical food containing L-methylfolate: a preliminary report

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Eye and Vision 2019年第1期6卷 164-174页

作者： jianhua wang Craig Brown Ce Shi Justin Townsend Giovana Rosa Gameiro Peng wang Hong Jiang Bascom Palmer Eye Institute University of MiamiMiller School of Medicine1638 NW 10th AvenueMcKnight Building-Room 202AMiamiFL 33136USA Department of Ophthalmology College of MedicineUniversity of Arkansas for Medical SciencesFayettevilleARUSA School of Ophthalmology and Optometry Wenzhou Medical UniversityWenzhouZhejiangChina Department of Ophthalmology Shanghai General HospitalShanghai Jiaotong University School of MedicineShanghaiChina

Background:Homocysteine and vitamin D may play a role in the development of diabetic and hypertensive retinopathy in patients with diabetes mellitus(DM)and *** food with L-methylfolate and vitamin D theoretically may improve diabetic and hypertensive retinopathy,however,the outcome of these nutritional approaches has not been fully examined.A retrospective case review was done of cases of retinopathy reversal in patients on Ocufolin^(TM) and a similar nonprescription multivitamin,Eyefolate^(TM).In this study,they were administered L-methylfolate(2.7 mg and 3.0 mg,respectively)and vitamin D3(4500 IU each).These dosages are significantly above the RDA but well below levels associated with *** presentation:Seven patients had nonproliferative diabetic retinopathy(NPDR)and some of them had *** patient had only hypertensive *** patients were instructed to take Ocufolin^(TM)medical food as a food *** genetic testing for MTHFR polymorphisms was *** photography was used to document the fundus condition of the enrolled eyes in 8 NPDR patients at the initial and follow-up ***(MA)and exudates were observed to be improved in some trial *** subjects had one or more MTHFR *** had diabetic retinopathy,hypertensive retinopathy,or *** were resolved,and exudates were decreased in 8/8 cases after taking the medical *** edema was found in 2/8 cases and improved or resolved in both cases after taking the medical food or the *** best corrected visual activity was stable or improved in 8/8 ***:We report a series of diabetic and hypertensive retinopathy cases with MTHFR polymorphisms and the improvement of retinal microvasculature(mainly MAs)in serial fundus photography after taking a medical food or supplement containing L-methylfolate and vitamin *** appears that the use of nutritional supplements and medical foods containin

关键词： Diabetes Homocysteine L-methylfolate Microaneurysms MTHFR C677T Retinopathy Vitamin D

Synthesis and Thermal Behavior of 1,8-Dihydroxy- 4,5-dinitroanthraquinone Manganese Salt

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Chemical Research in Chinese Universities 2014年第3期30卷 468-471页

作者： wang Yinglei ZHAO Fengqi JI Yueping YI jianhua wang Wei XU Siyu AN Ting PEI Qing Science and Technology on Combusition and Explosion Laboratory Xi 'an Modern Chemistry Research Institute Xi 'an 710065 P. R. China

A novel energetic combustion catalyst, 1,8-dihydroxy-4,5-dinitroanthraquinone manganese salt （DHDNEMn）, was synthesized by virtue of the metathesis reaction in a yield of 91%, and its structure was characterized by IR, element analysis and differential scanning calorimetry（DSC）. The thermal decomposition reaction kinetics was studied by means of different heating rate DSC. The results show that the apparent activation energy and pre-exponential factor of the exothermic decomposition reaction of DHDNEMn obtained by Kissinger＇s method are 162.3 kJ/mol and 1011.8 s^-1, respectively. The kinetic equation of major exothermic decomposition reaction of DHDNEMn is dα/dT= 10^118/β 2/5（1-α）[-ln（1-α）[-ln（1-α）]^3/5 exp（-1.623×10^5/RT）. The entropy of activation（△S^≠）, enthalpy of activation（△H^≠） and free energy of activation（A△G^≠） of the first thermal decomposition are -24.49 J·mol^-1·K^-1, 185.20 kJ/mol and 199.29 kJ/mol（T=575.5 K）, respectively. The self-accelerating decomposition temperature（TSADT） and critical temperature of thermal explosion（Tb） are 562.9 and 580.0 K, respectively. The above-mentioned information on the thermal behavior is quite useful for analyzing and evaluating the stability and thermal safety of DHDNEMn.

关键词： Manganese salt of 1,8-dihydroxy-4,5-dinitroanthraquinone Thermal behavior Energetic combustion catalyst