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Discussion on dynamic reliability tolerance design technology of electromagnetic relay

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第3期8卷 439-443页

作者： ye Xue-rong LIANG Hui-min ZHAI Guo-fu School of Electrical Engineering and Automation Harbin Institute of Technology Harbin 150001 China

Reliability tolerance design of electromagnetic relay during its design period plays an essential role in guaranteeing the consistencies of reliability and output characteristic. The reliability tolerance design can ensure that the products would work well under the influence of disturbing factors (including internal interference, external interference, and machining dispersion). Com- pared with static characteristic, dynamic characteristic of electromagnetic relay can describe its operating process better. This article researches influence of the three kinds of disturbing factors on the dynamic characteristic of electromagnetic relay based on calculating dynamic characteristic. Then, the dynamic reliability tolerance design method of electromagnetic relay is discussed considering three kinds of disturbing factors. Conclusions reached can help to assure the reliability of electromagnetic relay from the beginning of design.

关键词： Electromagnetic relay Tolerance design Reliability Dynamic characteristic

Testbeds for Integrated Transmission and Distribution Networks: Generation Methodology and Benchmarks

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CSEE Journal of Power and Energy Systems 2020年第3期6卷 518-527页

作者： Jing yu ye Guo Hongbin Sun Shenzhen Environmental Science and New Energy Technology Engineering Laboratory Tsinghua-Berkeley Shenzhen Institute Tsinghua UniversityShenzhenChina State Key Laboratory of Power Systems Department of Electrical EngineeringTsinghua UniversityBeijing 100084China

For future power systems with high penetration of distributed energy resources(DER),the coordination of the transmission system(TS)and distribution system(DS)is quite *** this paper,multiple testbeds that consist of various sizes of TS and DS models are designed for power flow(PF)and optimal power flow(OPF)analysis of the integrated transmission and distribution(T&D)*** benchmarks with characteristics for applications are proposed and their simulation results are presented in this *** can use the testbeds designed in this paper to build their specific cases with published data,and they can also compare the results of their new approaches or algorithms with those obtained by the proposed benchmarks in this paper.

关键词： Distribution system multi-area power systems optimal power flow power flow test system design transmission system

Dynamic stress–strain properties of Ti–Al–V titanium alloys with various element contents

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Rare Metals 2013年第6期32卷 555-559页

作者： Rui Liu Song-Xiao Hui Wen-Jun ye Cheng-Lin Li Yan-Yan fu Yang yu Xiao-yun Song State Key Laboratory of Nonferrous Metals General Research Institute for Nonferrous Metals

A series of Ti–Al–V titanium alloy bars with nominal composition Ti–7Al–5V ELI,Ti–5Al–3V ELI,commercial Ti–6Al–4V ELI and commercial Ti–6Al–4V were *** alloys were then heat treated to obtain bimodal or equiaxed microstructures with various contents of primary a *** compression properties of the alloys above were studied by split Hopkinson pressure bar system at strain rates from 2,000 to 4,000 *** results show that Ti–6Al–4V alloy with equiaxed primary a(ap)volume fraction of 45 vol%or 67 vol%exhibits good dynamic properties with high dynamic strength and absorbed energy,as well as an acceptable dynamic ***,all the Ti53ELI specimens and Ti64ELI specimens with ap of 65 vol%were not fractured at a strain rate of4,000 *** appears that the undamaged specimens still have load-bearing *** strength of Ti–Al–V alloy can be improved as the contents of elements Al,V,Fe,and O increase,while dynamic strain is not sensitive to the composition in the appropriate *** effects of primary alpha volume fraction on the dynamic properties are dependent on the compositions of Ti–Al–V alloys.

关键词： Dynamic properties Alloying content Microstructure Titanium alloy

Toluene decomposition performance and NOx by-product formation during a DBD-catalyst process

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Journal of Environmental Sciences 2015年第2期27卷 187-194页

作者： yufang Guo Xiaobin Liao Mingli fu Haibao Huang Daiqi ye College of Environmental Science and Engineering Guangzhou University Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology (Sun Yat-sen University) Guangdong Provincial Key Laboratory of Atmospheric Environment and Pollution Control College of Environmental Science and Engineering South China University of Technology College of Environmental Science and Engineering Sun Yat-Sen University

Characteristics of toluene decomposition and formation of nitrogen oxide（NOx） by-products were investigated in a dielectric barrier discharge（DBD） reactor with/without catalyst at room temperature and atmospheric pressure. Four kinds of metal oxides, i.e., manganese oxide（Mn Ox）, iron oxide（Fe Ox）, cobalt oxide（Co Ox） and copper oxide（Cu O）, supported on Al2O3/nickel foam, were used as catalysts. It was found that introducing catalysts could improve toluene removal efficiency, promote decomposition of by-product ozone and enhance CO2 selectivity. In addition, NOx was suppressed with the decrease of specific energy density（SED） and the increase of humidity, gas flow rate and toluene concentration, or catalyst introduction. Among the four kinds of catalysts, the Cu O catalyst showed the best performance in NOx suppression. The Mn Ox catalyst exhibited the lowest concentration of O3 and highest CO2 selectivity but the highest concentration of NOx. A possible pathway for NOx production in DBD was discussed. The contributions of oxygen active species and hydroxyl radicals are dominant in NOx suppression.

关键词： Dielectric barrier discharge Nitrogen oxides Catalyst Toluene

Research on calculation method of text similarity based on smooth inverse frequency

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The Journal of China Universities of Posts and Telecommunications 2020年第2期27卷 56-64页

作者： yuan ye yu Minmin Liu Jiming Key Laboratory of E-commerce and Modem Logistics Chongqing University of Posts and TelecommunicationsChongqing 400065China

In order to improve the accuracy of text similarity calculation,this paper presents a text similarity function part of speech and word order-smooth inverse frequency(PO-SIF)based on sentence vector,which optimizes the classical SIF calculation method in two aspects:part of speech and word *** classical SIF algorithm is to calculate sentence similarity by getting a sentence vector through weighting and reducing ***,the different methods of weighting or reducing noise would affect the efficiency and the accuracy of similarity *** our proposed PO-SIF,the weight parameters of the SIF sentence vector are first updated by the part of speech subtraction factor,to determine the most crucial ***,PO-SIF calculates the sentence vector similarity taking into the account of word order,which overcomes the drawback of similarity analysis that is mostly based on the word *** experimental results validate the performance of our proposed PO-SIF on improving the accuracy of text similarity calculation.

关键词： word2vec SIF part-of-speech word order similarity

Non-contact optical dynamic measurements at different ranges:a review

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Acta Mechanica Sinica 2021年第4期37卷 537-553,I0001页

作者： yu fu Yang Shang Wenxin Hu Bin Li Qifeng yu Shenzhen Key Laboratory of Intelligent Optical Measurement and Detection Shenzhen UniversityShenzhen 518060China Hunan Provincial Key Laboratory of Image Measurement and Vision Navigation College of Aerospace Science and EngineeringNational University of Defense TechnologyChangsha 410073China

Optical dynamic measurements are widely used for non-contact vibration,continuous deformation,or moving *** measurement techniques were developed for different deformation *** paper reviews three types of technique for different measurement ranges:interferometric techniques for deformation or vibration(nanometer to submillimeter amplitude)whose measurement accuracies rely on phase extraction of interferometric signal;imaging based techniques for deformation or vibration(micrometer to centimeter amplitude)with the aid of moire,structured light,and man-made speckles,whose sensitivities is from 1/100 to 1/10 pixel;and videometrics for large deformation or movement detection(greater than centimeter amplitude).Many research groups have improved measurement capabilities for these three techniques to meet particular industrial application requirements.

关键词： Vibration measurement Laser interferometry Digital image correlation High-speed imaging Videometrics

Non-invasive ventilation improves hemorheology status in hypoxemic patients with acute myocardial infarction after PCI

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Journal of Geriatric Cardiology 2017年第4期14卷 274-279页

作者： Xi-fu WANG Ming ye Dong YAN Hui-Min ZHANG Ping JIA Xue-Jun REN yu-Jie ZENG Department of Emergency and Critical Care Center Beij'ing Anzhen Hospital Capital Medical University Beijing China Department of Cardiology Peking University Shougang Hospital Beijing China Department of Cardiology Beifing Anzhen Hospital Capital Medical University Beijing China

Background Hypoxemia sometimes occurs in the emergency room in the patients with acute myocardial infarction （AMI） after percutaneous coronary intervention （PCI）, even in those with administration of conventional high-flow oxygen inhalation. The objective of the present study was to evaluate the effectiveness of non-invasive ventilation （NIV） in improving blood oxygen content and hemorheology in patients with AMI and hypoxemia. Methods This prospective study enrolled 50 consecutive eligible patients with AMI （aged 72.3 ± 9.5 years）, who had undergone PCI and been administered high-flow oxygen but still had hypoxemia. Blood was taken before NIV and at 0.5, 1, and 2 h after NIV. Blood gases, hemorheological variables including erythrocyte deformability, erythrocyte aggregation, erythrocyte osmotic fragility, membrane fluidity, and oxidative stress level were measured. Results Blood PaO2 increased to normal by 1 h after NIV. Assessed hemorheological variables had all improved and plasma malondialdehyde concentration decreased significantly after 2 h of NIV. Conclusions Our data suggest that NIV can help to improve blood oxygen content, hemorheological status, and minimize plasma lipid peroxidation injury in hypoxemic patients with AMI who have undergone PCI.

关键词： Acute myocardial infarction Hypoxemia Non-invasive ventilation Percutaneous coronary intervention

‘Invisible’ orthodontics by polymeric ‘clear’ aligners molded on 3D-printed personalized dental models

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Regenerative Biomaterials 2022年第1期9卷 1-12页

作者： Xiaoye yu Guanghui Li Yikan Zheng Jingming Gao ye fu Qunsong Wang Lei Huang Xiaogang Pan Jiandong Ding State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular ScienceFudan UniversityShanghai 200438China Department of Orthodontics Shanghai Ninth People’s HospitalCollege of StomatologyShanghai Jiao Tong University School of MedicineNational Clinical Research Center for Oral DiseasesShanghai Key Laboratory of Stomatology&Shanghai Research Institute of StomatologyShanghai 200011China R&D Center EA Medical Device Technologies Co.Ltd.Wuxi 214174China

The malalignment of teeth is treated classically by metal braces with alloy wires,which has an unfavorable influence on the patients appearance during the *** the development of digitization,computer simulation and three-dimensional(3D)printing technology,herein,a modern treatment was tried using clear polymeric aligners,which were fabricated by molding polyurethane films via thermoforming on the 3D-printed personalized dental *** key parameters of photocurable 3D printing of dental models and the mechanical properties of the clear aligner film material were *** precision of a 3D-printed dental model mainly relied on characteristics of photocurable resin,the resolution of light source and the exposure condition,which determined the eventual shape of the molded clear aligner and thus the orthodontic treatment *** biocompatibility of the polyurethane filmmaterial was confirmed through cytotoxicity and hemolysis tests in *** a series of 3D-printed personalized dental models and finite element analysis to predict and plan the fabrication and orthodontic processes,corresponding clear aligners were fabricated and applied in animal experiments,which proved the efficacy and biocompatibility in *** treatments of 120 orthodontic cases were finally carried out with success,which highlights the advantage of the clear aligners as an esthetic,compatible and efficient appliance.

关键词： 3D printing polymer biomaterial clear aligner orthodontics

基于50BiN望远镜的疏散星团NGC 7789的变星搜寻研究

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西华师范大学学报（自然科学版） 2025年第1期46卷 79-85页

作者：叶倩王坤彭宇慧西华师范大学物理与天文学院四川南充637009

基于西华师范大学50BiN望远镜获得的长时序测光观测数据,在疏散星团NGC 7789及其周围的20′×20′视场中搜寻到19颗变星,其中10颗是本次观测发现的。基于变星在NGC 7789颜色星等图上的位置、星团成员星概率和Gaia视差,对这19颗变星的星... 详细信息

基于西华师范大学50BiN望远镜获得的长时序测光观测数据,在疏散星团NGC 7789及其周围的20′×20′视场中搜寻到19颗变星,其中10颗是本次观测发现的。基于变星在NGC 7789颜色星等图上的位置、星团成员星概率和Gaia视差,对这19颗变星的星团成员星性质进行初步分析。结果表明,17颗变星可能是星团成员,2颗可能是场星。根据变星光变曲线的形状,周期的长度以及在颜色星等图上的位置,对这19颗变星的分类进行了初步讨论。结果表明,13颗是短周期变星(3颗δ Scuti, 7颗食双星、3颗未知类型变星),6颗是长周期变星。研究扩大了星团变星的样本数量,为开展单个变星的星震学研究和星团变星的统计研究奠定了基础。

关键词： 50BiN 疏散星团变星 NGC 7789 δScuti