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Digital assembly technology based on augmented reality and digital twins: a review

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Virtual Reality & Intelligent Hardware 2019年第6期1卷 597-610页

作者： Chan QIU shien ZHOU Zhenyu LIU Qi GAO Jianrong tan State Key Laboratory of CAD and CG Zhejiang UniversityHangzhou 310027China

Product assembly simulation is considered as one of the key technologies in the process of complex product design and *** assembly realizes the assembly process design,verification,and optimization of complex products in the virtual environment,which plays an active and effective role in improving the assembly quality and efficiency of complex *** recent years,augmented reality(AR)and digital twin(DT)technology have brought new opportunities and challenges to the digital assembly of complex products owing to their characteristics of virtual reality fusion and interactive *** paper expounds the concept and connotation of AR,enumerates a typical AR assembly system structure,analyzes the key technologies and applications of AR in digital assembly,and notes that DT technology is the future development trend of intelligent assembly research.

关键词： Augmented reality Digital twin Digital assembly Virtual simulation Assembly analysis

Sampling Moiré method for full-field deformation measurement: A brief review

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Theoretical & Applied Mechanics Letters 2022年第1期12卷 42-48页

作者： Qinghua Wang shien Ri Research Institute for Measurement and Analytical Instrumentation National Metrology Institute of Japan(NMIJ)National Institute of Advanced Industrial Science and Technology(AIST)1-1-1 UmezonoTsukuba 305-8568Japan

The sampling Moiré(SM) method is one of the vision-based non-contact deformation measurement methods, which is a powerful tool for structural health monitoring and elucidation of damage mechanisms of materials. In this review, the basic principle of the SM method for measuring the twodimensional displacement and strain distributions is introduced. When the grid is not a standard orthogonal grating and cracks exist on the specimen surface, the measurement methods are also stated. Two of the most typical application examples are described in detail. One is the dynamic deflection measurement of a large-scale concrete bridge, and the other is the residual thermal strain measurement of small-scale flip chip packages. Several further development points of this method are pointed out. The SM method is expected to be used for deformation measurement of various structures and materials for residual stress evaluation, crack location prediction, and crack growth evaluation on broad scales.

关键词： Displacement measurement Strain distribution Bridge Flip chip package

Impacts of Large-scale Wind Power Grid Integration on Relay Protection and Countermeasures

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电力系统自动化 2012年第8期36卷 136-142页

作者： He, shien Suonan, Jiale Kang, Xiaoning Song, Guobing School of Electrical Engineering Xi'an Jiaotong University Xi'an 710049 China Wind Power Technology Center Gansu Electric Power Corporation Lanzhou 730050 China

Several large-scale wind turbine tripping accidents occurred in Jiuquan wind power base in *** to the on-site survey and analysis of these accidents related to relay protection,causes were found to be the collection system defects and low correct operation rate of small current grounded line selectors of the unearthed neutral point collection *** referring to both the characteristics of Jiuquan wind power base and arrangement of relay protection,the short-circuit features of wind power and its impacts on relay protection are *** collection system and the retrofit of the small current grounded line selector are improved by specific ***,further research subjects are put forward.

关键词：大型风力发电机组继电保护小电流接地选线整合电网事故发生现场调查运转率

Assisting effect of Al_(2)O_(3) on MnO_(x) for NO catalytic oxidation

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Green Energy & Environment 2021年第6期6卷 903-909页

作者： Denghui Wang Hui Li Qi Yao shien Hui Yanqing Niu State Key Laboratory of Multiphase Flow in Power Engineering School of Energy and Power EngineeringXi'an Jiaotong UniversityXi'an710049China

Various Mn-based catalysts for NO oxidation were prepared using MnO_(x)as active compound,while Ti O_(2)and Al_(2)O_(3)were adopted as catalyst *** performance of the catalysts was tested to study the effect of support on Mn-based catalyst *** of the catalysts followed as Mn_(0.4)/Al>Mn_(0.2)/Al>Mn_(0.4)/Ti>Mn_(0.2)/Ti>MnO_(x)>Al_(2)O_(3)on the whole,indicating the synergism of MnO_(x)and Al_(2)O_(3)for NO catalytic *** were analyzed according to characterization *** oxygen on catalyst rather than lattice oxygen was detected as the active oxidizer for NO *** catalyst support,Al_(2)O_(3)provided more sites to carry surface adsorbed oxygen than TiO_(2),resulting in the presence of more active oxygen on Mn O_(x)/Al_(2)O_(3)than on MnO_(x)/TiO_(2).Moreover,MnO_(x)/Al_(2)O_(3)possessed high surface area and pore volume,which greatly benefited the adsorption of NO on catalyst and further favored the oxidation of NO by active *** these advantages helped Mn_(0.4)/Al exhibited the best catalytic efficiency.

关键词： NO catalytic oxidation MnO_(x)/Al_(2)O_(3) NO_(2) Active oxygen

Array Waveguide Grating Based Fiber Lasers

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光学学报 2003年第S1期23卷 -页

作者： shien-Kuei Liaw Department of Electronic Engineering Taiwan University of Science and Technology No. 43 Sec. 4 Keelung Rd. Taipei 106 Taiwan

Two array waveguide grating (AWGs) based fiber ring lasers are experimentally demonstrated. Either of them achieves wavelength discrete tuning of 32 nm, or yields simultaneously lasing up to four channels with -7 dBm ... 详细信息

关键词： AWG in be as Array Waveguide Grating Based Fiber Lasers of dBm have for

Fault component integrated impedance-based pilot protection scheme for EHV/UHV transmission line with thyristor controlled series capacitor(TCSC) and controllable shunt reactor(CSR)

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Science China(Technological Sciences) 2013年第2期56卷 342-350页

作者： HE shien SUONAN JaLe KANG XiaoNing JIAO ZaiBin Department of Electrical Engineering Xi'an Jiaotong University Wind Power Technology Center Gansu Electric Power Corporation

This paper analyzes the fundamental frequency impedance presents a novel transmission line pilot protection scheme characteristic of a thyristor controlled series capacitor （TCSC） and based on fault component integrated impedance （FCII） calculated for a transmission line with TCSC and controllable shunt reactor （CSR）. The FCII is defined as the ratio of the sum of the fault component voltage phasors of a transmission line with TCSC and CSR to the sum of the fault component current phasors where all the phasors are determined at both line＇s terminals. It can be used to distinguish internal faults occurring on the line from external ones. If the fault is an external one the FCII reflects the line＇s capacitive impedance and has large value. If the fault is an internal one on the line the FCII reflects the impedance of the equivalent system and the line and is relatively small. The new pilot protection scheme can be easily set and has the fault phase selection ability and also it is not affected by the capacitive current and the fault transition resistance. It is not sensitive to compensation level and dynamics of TCSC and CSR. The effectiveness of the new scheme is validated against data obtained in ATP simulations and Northwest China 750 kV Project.

关键词： EHV/UHV transmission line pilot protection fault component integrated impedance (FCII) thyristor controlled seriescapacitor (TCSC) controllable shunt reactor (CSR)

The relations among the three kinds of conditional risk measures

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Science China Mathematics 2014年第8期57卷 1753-1764页

作者： GUO TieXin ZHAO shien ZENG XiaoLin School of Mathematics and Statistics Central South University Elementary Educational College Capital Normal University College of Mathematics and Statistics Chongqing Technology and Business University

Let（Ω , E, P） be a probability space, F a sub-σ-algebra of E, L^p（E）（1 p ＋∞） the classical function space and LF^p（E） the L^0（F）-module generated by L^p（E）, which can be made into a random normed module in a natural way. Up to the present time, there are three kinds of conditional risk measures, whose model spaces are L^∞（E）, L^p（E）（1 p ＋∞） and LF^p（E）（1 p ＋∞） respectively, and a conditional convex dual representation theorem has been established for each kind. The purpose of this paper is to study the relations among the three kinds of conditional risk measures together with their representation theorems. We first establish the relation between L^p（E） and LF^p（E）, namely LF^p（E） = Hcc（L^p（E））, which shows that LF^p（E）is exactly the countable concatenation hull of L^p（E）. Based on the precise relation, we then prove that every L^0（F）-convex L^p（E）-conditional risk measure（1 p ＋∞） can be uniquely extended to an L^0（F）-convex LF^p（E）-conditional risk measure and that the dual representation theorem of the former can also be regarded as a special case of that of the latter, which shows that the study of L^p-conditional risk measures can be incorporated into that of LF^p（E）-conditional risk measures. In particular, in the process we find that combining the countable concatenation hull of a set and the local property of conditional risk measures is a very useful analytic skill that may considerably simplify and improve the study of L^0-convex conditional risk measures.

关键词： random normed module countable concatenation property L^∞(E)-conditional risk measure L^p(E)-conditional risk measure(1≤ p 〈 +∞) LF^p(E)-conditional risk measure(1 ≤p≤ +∞) extension

Instantaneous power calculation based on intrinsic frequency of single-phase virtual synchronous generator

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Journal of Modern Power Systems and Clean Energy 2017年第6期5卷 970-978页

作者： Yangyang ZHAO Jianyun CHAI shien WANG Kai SUN The State Key Lab of Power Systems Department of Electrical EngineeringTsinghua UniversityBeijingChina

In order to enhance the stability of single-phase microgrid,virtual synchronous generator(VSG)control method is investigated in this *** electromagnetic model and electromechanical model are established to illustrate the performance of *** the 2 nd fluctuation of fundamental-frequency in the output power,an instantaneous power calculation strategy is proposed based on the intrinsic frequency of single-phase ***,a virtual power calculation method is presented to achieve islanded/grid-connected seamless *** analysis and comparison simulation results demonstrate the correctness of the presented power calculation *** last,the effectiveness of the proposed approach is verified by comparison experiments of islanded/gridconnected operations in a 500 VA single-phase inverter.

关键词： Virtual synchronous generator Single phase inverter Instantaneous power calculation Seamless transition

Adenomyosis uterine innervation in mice correlates to nerve growth factor expression,inflammation,and vascularization

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Neural Regeneration Research 2010年第1期5卷 15-20页

作者： Yan Li Shaofen Zhang Xian Xia shien Zou Department of Gynaecology Obstetrics and Gynaecology H~spital of Fudan University Shanghai 200011 China

BACKGROUND： Studies have shown that abnormal innervation is an important factor impacting occurrence and development of pathological pain in endometriosis. OBJECTIVE： To observe uterine innervation of adenomyosis mice and to analyze the cause of innervation changes due to nerve growth factor （NGF） expression, inflammation, and vascularization. DESIGN, TIME AND SETTING： This randomized, controlled, animal experiment was performed at the Research Institute of Obstetrics and Gynecology Hospital, and Central Laboratory of Zhongshan Hospital, Fudan University from March to December 2008. MATERIALS： Tamoxifen was provided by Fudan Forward, China. Rabbit anti-mouse NGF was purchased from Santa Cruz Corporation, USA; rabbit anti-protein gene product 9.5 （PGP9.5） and rabbit anti-substance P （SP） were purchased from Chemicon, USA. METHODS： A total of 40 newborn ICR mice were randomly assigned to adenomyosis model and control groups, with 20 animals in each group. Mice in the adenomyosis model group were orally administrated 2.7 μmol/kg tamoxifen on days 2-5 after birth, while the controls were not treated. MAIN OUTCOME MEASURES： Both uteri from all mice were harvested at days 135-145 after birth Expressions of polyclonal PGP9.5 and SP were immunohistochemically detected to demonstrate pan- and sensory nerve fibers. Microvessel density was quantified in the endometrium and myometrium using immunochemical staining for polyclonal rabbit anti-CD31, which stained vessels. Gene expression for NGF, high-affinity tyrosine kinase receptor （trkA）, p75 neuretrophin receptor （p75NTR）, bradykinin receptor-1 （BKR-1）, and 2 （BKR-2）, as well as substance P receptor （neurokininl receptor, NK1-R）, were detected by reverse transcription-polymerase chain reaction. NGF-13 protein expression was detected by Western blot analysis. RESULTS： More nerve fibers were stained with PGP9.5 in the endometrium and myometrium, and with SP in the endometrium, in adenomyosis mice compared with controls （P 〈 0.0

关键词： adenomyosis innervation nerve growth factor inflammation vascularization