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A collinear tandem time-of-flight mass spectrometer for infrared photodissociation spectroscopy of mass-selected ions

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Science China Chemistry 2014年第1期57卷 172-177页

作者： wang guanjun CHI ChaoXian XING XiaoPeng DING ChuanFan ZHOU MingFei Shanghai Key Laboratory of Molecular Catalysts and Innovative Materials Department of Chemistry Fudan University College of Materials Sciences and Opto-Electronic Technology Graduate University of Chinese Academy of Sciences

An apparatus based on collinear tandem time-of-flight mass spectrometer has been designed for the measurement of infrared photodissociation spectroscopy of mass-selected ions in the gas *** ions from a pulsed laser vaporization supersonic ion source are skimmed and mass separated by a Wiley-McLaren time-of-flight mass *** ion of interest is mass selected,decelerated and dissociated by a tunable IR *** fragment and parent ions are reaccelerated and mass analyzed by the second time-of-flight mass spectrometer.A simple new assembly integrated with mass gate,deceleration and reacceleration ion optics was designed,which allows us to measure the infrared spectra of mass selected ions with high sensitivity and easy timing synchronization.

关键词： infrared photodissociation spectroscopy,time-of-flight mass spectrometer,mass selection,ion spectroscopy

Acellular nerve allograft promotes selective regeneration

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Neural Regeneration Research 2011年第4期6卷 257-261页

作者： Haili Xin guanjun wang Xinrong He Jiang Peng Quanyi Guo Wenjing Xu Bureau of Drugs Department of Surgery Chinese PLA General Hospital Beijing 100853 China Department of Spine Surgery General Hospital of Chinese Armed Police Forces Beijing 100039 China Institute of Orthopedics General Hospital of Chinese PLA Beijing 100853 China

Acellular nerve ailograft preserves the basilar membrane tube and extracellular matrix, which promotes selective regeneration of neural defects via bridging. In the present study, a Sprague Dawley rat sciatic nerve was utilized to prepare acellular nerve allografts through the use of the chemical extraction method. Subsequently, the allograft was transplanted into a 10-mm sciatic nerve defect in Wistar rats, while autologous nerve grafts from Wistar rats served as controls. Compared with autologous nerve grafts, the acellular nerve allografts induced a greater number of degenerated nerve fibers from sural nerves, as well as a reduced misconnect rate in motor fibers, fewer acetylcholine esterase-positive sural nerves, and a greater number of carbonic anhydrase-positive sensory nerve fibers. Results demonstrated that the acellular nerve allograft exhibited significant neural selective regeneration in the process of bridging nerve defects.

关键词： acellular nerve allograft selective regeneration peripheral nerve tissue engineering neural regeneration

Long Period Fiber Gratings Written in Photonic Crystal Fibers by Use of CO2 Laser

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Photonic Sensors 2013年第3期3卷 193-201页

作者： Yiping wang Changrui LIAO Xiaoyong ZHONG Jiangtao ZHOU Yingjie LIU Zhengyong LI guanjun wang Kaiming YANG Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education/Guangdong Province ShenzhenUniversity Shenzhen 518060 China

Photonic crystal fibers are usually divided into two different types of fibers： solid-core photonic crystal fibers （PCFs） and air-core photonic bandgaps fibers （PBFs）. We presented the fabrication methods and applications of long period fiber gratings （LPFGs） written in these two types of photonic crystal fibers by use of a CO2 laser. A stain sensor with a high sensitivity was demonstrated by use of an LPFG written in solid-core PCFs. An in-fiber polarizer based on an LPFG was fabricated by use of a focused CO2 laser beam to notch periodically on a PCF. A novel LPFG was written in an air-core PBF by use of a CO2 laser to collapse periodically air holes in the fiber cladding.

关键词： Long period fiber gratings fiber Bragg gratings photonic crystal fibers photonic bandgap fibers CO2 lasers

Recognition System for Diagnosing Pneumonia and Bronchitis Using Children’s Breathing Sounds Based on Transfer Learning

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Intelligent Automation & Soft Computing 2023年第9期37卷 3235-3258页

作者： Jianying Shi Shengchao Chen Benguo Yu Yi Ren guanjun wang Chenyang Xue School of Information and Communication Engineering Hainan UniversityHaikou570228China School of Biomedical Information and Engineering Hainan Medical CollegeHaikou571199China Department of Pediatrics Haikou Hospital of the Maternal and Child HealthHaikou570203China Wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhan430074China School of Instrument and Electronics North University of ChinaTaiyuan030051China

Respiratory infections in children increase the risk of fatal lung disease,making effective identification and analysis of breath sounds ***,most studies have focused on adults ignoring pediatric patients whose lungs are more vulnerable due to an imperfect immune system,and the scarcity of medical data has limited the development of deep learning methods toward reliability and high classification *** this work,we collected three types of breath sounds from children with normal(120 recordings),bronchitis(120 recordings),and pneumonia(120 recordings)at the posterior chest position using an off-the-shelf 3M electronic *** features were extracted from the wavelet denoised signal:spectrogram,mel-frequency cepstral coefficients(MFCCs),and Delta *** recog-nition model is based on transfer learning techniques and combines fine-tuned MobileNetV2 and modified ResNet50 to classify breath sounds,along with software for displaying analysis *** experiments on a real dataset demonstrate the effectiveness and superior performance of the proposed model,with average accuracy,precision,recall,specificity and F1 scores of 97.96%,97.83%,97.89%,98.89%and 0.98,respectively,achieving superior performance with a small *** proposed detection system,with a high-performance model and software,can help parents perform lung screening at home and also has the potential for a vast screening of children for lung disease.

关键词： Deep learning breath sounds transfer learning signal denoising

Research on Iron Loss of Switched Reluctance Starter/Generator for Energy Storage

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Protection and Control of Modern Power Systems 2024年第4期9卷 147-159页

作者： Hao Chen Xing wang Yongqiang Liu Vuong Dang Quoc Wenju Yan Muhammad Saqib Antonino Musolino guanjun wang Yong Qi Ali Asghar Memon Alexandros G.Paspatis the Shenzhen Research Institute China University of Mining and TechnologyShenzhen 515100China the School of Electrical Engineering China University of Mining and TechnologyXuzhou 221116China Xinjiang Institute of Engineering Urumqi 830000China the International Joint Research Center of Central and Eastern European Countries on New Energy EV Technology and Equipment Xuzhou 221008China the International Cooperation Joint Laboratory of New Energy Power Generation and EVs of Jiangsu Province Colleges and Universities Xuzhou 221008China the Xuzhou Key Laboratory of New Energy EV Technology and Equipment Xuzhou 221008China the the School of Electrical Engineering China University of Mining and Tech-nologyXuzhou 221116China the Laboratory of High Performance Electric Machines(HiPems) Hanoi VN 10000Viet Nam the University of Engineering and Technology Lahore 54890Pakistan the Department of Energy Pisa Uni-versity of PisaPisa IT 56126Italy the Wuxi Inspection and Testing Certification Research Institute Wuxi 214000China the Nanjing University of Science&Tech-nology Nanjing 210094China the Mehran University of Engi-neering&Technology Jamshoro PK 76062Sindh the National Technical University of Athens Zografou GR 15780Attica

In order to better realize the energy recovery and storage of hybrid EVs(HEVs),a switched reluctance starter/generator(SRS/G)with both starting and power generation functions is investigated in this ***,the iron loss of SRS/G is mainly studied to reduce the motor loss and improve the power generation ***,the energy storage of hybrid EVs can be effectively ***,a magnetic flux density(MFD)waveforms solution method is proposed to solve the difficulty in calculating the iron loss of the SRS/*** with the commonly used finite element method,the proposed solution method has the advantages of simple,fast and small computational ***,considering the different operating conditions of SRS/G,the iron loss models for both the time-domain and frequency-domain are *** addition,the calculation formula of the variable coefficient Bertotti three-term loss separation is *** the hysteresis loss coefficient,the Steinmetz coefficient and the stray loss coefficient are respectively fitted by the Fourier fitting *** method is also applied to solve the iron loss of SRS/***,through an experimental verification,it is indicated that the development of proposed method has high accuracy.

关键词： Switched reluctance starter/generator energy storage iron loss finite element method magnetic flux density(MFD)

BEHAVIOR OF STOCHASTIC APPROXIMATIONALGORITHM IN ROOT SET OF REGRESSIONFUNCTION

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Systems Science and Mathematical Sciences 1999年第1期12卷 92-96页

作者： wang guanjun CHEN Hanfu (Institute of Systems Science, Academia of Sinica, Beijing 100080, China) 中科院系统科学所北京

By convergence of a stochastic approximation (SA) algorithm one usually means that the distance d(xn, J) between the estimate xn given by the algorithm and the root set J of the regression function tends to zero. This paper characterizes the properties of the limit points of xn. An illustrative example is given to show that xn may move about in J even thought d(xn, J) 0. Finally, the paper gives conditions guaranteeing not only d(xn, J)0 but also the convergence of {xn} itself in the one-dimensional case.

关键词： Stochastic approximation convergence.

ADSORPTION OF METHYLENE BLUE FROM AQUEOUS SOLUTION ON ATTAPULGITE

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Chinese Journal of Reactive Polymers 2007年第1期16卷 85-89页

作者： wang Deping LV Pengfei YANYongsheng LIU Hui wang guanjun College of Chemistry and Chemical Engineering Jiangsu University Zhenjiang 212003 China Pingdingshan Teachers college Pingdingshan Henan 467000 China

Batch adsorption experiments were carried out for the removal of methylene blue (MB) from aqueous solution using attapulgite as adsorbent. The effects of various parameters such as temperature, contact time, the pH value, and attapulgite dosage on the adsorption performance were investigated. The standard curve and regression equation were established by spectrophotometry. The adsorption experimental results showed that the adsorption equilibrium data were well in accord with Langmuir adsorptive model. The optimal result was acquired under the experimental condition of attapulgite dosage 0.18g, MB concentration 50.0mg/L, pH 10, and adsorption time 20min at room temperature.

关键词： Adsorption Methylene blue Isotherm

The NBEE and NWEE classes of lifetime distributions and their properties

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Journal of Southeast University(English Edition) 2012年第2期28卷 251-255页

作者：王冠军东南大学数学系南京211189

A class of lifetime distributions, new better than equilibrium in expectation （NBEE）, and its dual, new worse than equilibrium in expectation （NWEE）, are studied based on the comparison of the expectations of lifetime X and its equilibrium Xo. The relationships of the NBEE （NWEE） and other lifetime distribution classes are discussed. It is proved that the NBEE is very large, and increasing failure rate （IFR）, new better than used （NBU） and the L class are its subclasses. The closure properties under two kinds of reliability operations, namely, convolution and mixture, are investigated. Furthermore, a Poisson shock model and a special cumulative model are also studied, in which the necessary and sufficient conditions for the NBEE （NWEE） lifetime distribution of the systems are established. In the homogenous Poisson shock model, the system lifetime belongs to NBEE（NWEE） if and only if the corresponding discrete failure distribution belongs to the discrete NBEE（NWEE）. While in the cumulative model, the system has an NBEE lifetime if and only if the stochastic threshold of accumulated damage is NBEE.

关键词： lifetime distribution survival function closure property new better than equilibrium in expectation (NBEE) equilibrium distribution shock model cumulative damage model

Reliability Analysis of a Switched Reluctance Starter/Generator

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Protection and Control of Modern Power Systems 2024年第1期9卷 112-121页

作者： Hao Chen Fan Yang Lijun Xu Qiwei Lu Xiqiang Chang Xing wang Lijiang Dong Yi Wen Jiang Chen Gang Miao Jianmin Hu guanjun wang Wei Li Xiaohua Bao School of Electrical Engineering China University of Mining and TechnologyXuzhou 221116China Xinjiang Institute of Engineering Urumqi 830000China International Joint Research Center of Central and Eastern European Countries on New Energy Electric Vehicle Technology and Equipment Xuzhou 221008China International Cooperation Joint Laboratory of New Energy Power Generation and Electric Vehicles of Jiangsu Province Colleges and Universities Xuzhou 221008China School of Information and Electrical Engineering China University of Mining and TechnologyXuzhouChina China University of Mining and Technology(Beijing) BeijingChina State Grid Xingjiang Electric Power Co. Ltd.UrumqiXinjiangChina China University of Mining and Technology XuzhouChina State Grid Xinjiang Company Limited Electric Power Research Institute UrumqiXinjiangChina Xinjiang Fukang Pumped Storage Power Company Limited UrumqiXinjiangChina State Grid Urumqi Electric Power Supply Company UrumqiXinjiangChina Wuxi Inspection and Testing Certification Research Institute WuxiJiangsuChina Anhui Wannan Electric Machine Co. Ltd.WannanAnhuiChina Hefei University of Technology in Electrical and Automation Engineering

In this paper,the combined k-out-of-n:G model and reliability block diagram model is used to analyze the reliability of a switched reluctance starter/generator ***,the different operational modes of a switched reluctance motor starter/generator are analyzed,and the fault states of the system are briefly *** the fault criteria of the system in different operational states are put ***,a relia-bility block diagram model is established to calculate the system-level reliability,and the k-out-of-n:G model is adopted to analyze the reliability of each part of the switched reluctance starter/generator *** verify effectiveness,the first-order Markov model is also used to analyze the reliability of each part of the switched reluc-tance starter/generator *** the compu-tational complexity and accuracy of the system,the k-out-of-n:G model is more suitable for system component level reliability ***,a 6/4 switched reluctance motor is used as the simulated and experimental platform *** final results verify the effectiveness of the reliability analysis model.

关键词： system switched generator