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A model for converting thermal analysis to volume fraction of high carbon bearing steels during low-temperature tempering

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Journal of Materials Science & Technology 2023年第5期136卷 212-222页

作者： qinglong Liu Junyu Tian Wenting Wei The State Key Laboratory of Refractories and Metallurgy The Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of EducationWuhan University of Science and TechnologyWuhan 430081China School of Automotive Engineering Wuhan University of TechnologyWuhan 430070China Hubei Key Laboratory of Advanced Technology for Automotive Components(Wuhan University of Technology) Wuhan 430070China Hubei Collaborative Innovation Center for Automotive Components Technology Wuhan 430070China

Quantitative prediction of phase content is of great importance to control and optimize the heat treat-ment process of *** this work,a model for predicting the phase content of tempered high carbon steels was proposed by taking a martensitic 100Cr6 bearing steel as a model *** microstructural transformations during tempering were studied using thermal analysis,transmission electron microscopy(TEM),and X-ray diffraction(XRD).Kinetics analysis of thermal evolution by employing the isoconver-sional method,and assisted by TEM and XRD characterization,were performed to quantitatively estimate the volume fractions of different phases after tempering.A series of isothermal tempering experiments were designed to verify the *** predicted results were in good agreement with the experimental results of XRD and electrolytic extraction measurements.

关键词： Bearing steel Martensite tempering Retained austenite Thermal analysis Kinetics

A new absolute nodal coordinate formulation beam element with multilayer circular cross section

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Acta Mechanica Sinica 2020年第1期36卷 82-96页

作者： Peng Lan qinglong Tian Zuqing Yu School of Mechatronics Engineering Harbin Institute of TechnologyHarbin150001China

A systematic numerical integration method is applied to the absolute nodal coordinate formulation(ANCF)fully parameterized beam element with smooth varying and continuous cross ***,the formulation for the integration points and weight coefficients are given in the method which is used to model the multilayer beam with a circular cross *** negate the effect of the bending stiffness for the element used to model the high-voltage electrical wire,the general continuum mechanical approach is ***,the insulation cover for some particular types of the wire is described by the nearly incompressible Mooney-Rivlin material ***,a static problem is presented to prove the accuracy and convergence properties of the element,and a dynamic problem of a flexible pendulum is simulated whereby the balance of the energy can be *** experiment is carried out in which a wire is released as a pendulum and falls on a steel *** configurations of the wire are captured by a high-speed camera and compared with the simulation *** feasibility of the wire model can therefore be demonstrated.

关键词： Circular cross-section beam Absolute nodal coordinate formulation Electrical wire modeling Contact

Machining of SiC ceramic matrix composites:A review

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Chinese Journal of Aeronautics 2021年第4期34卷 540-567页

作者： qinglong AN Jie CHEN Weiwei MING Ming CHEN State Key Laboratory of Mechanical System and Vibration School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240China

Continuous fiber reinforced SiC ceramic matrix composites(FRCMCs-SiC)are currently the preferred material for hot section components,safety–critical components and braking components(in the aerospace,energy,transportation)with high value,and have triggered the demand for ***,the high brittleness,anisotropy,and heterogeneity of materials bring great challenges to machining,due to high mechanical and thermal loads,severe tool wear,and poor machining *** the increasing demand of FRCMCs-SiC parts,high-quality and high-efficient machining has become a hot *** review paper provides a detailed literature survey on the machining of *** material removal mechanism,defect form,and interfacial mechanical properties of FRCMCs-SiC were *** machining processes of FRCMCs-SiC were introduced,and their respective advantages and disadvantages were *** the low machinability(high hardness,high brittleness,anisotropy,and heterogeneity)of FRCMCs-SiC,preliminary experiments have proved that ultrasonic-assisted machining and laser-assisted machining have shown unique advantages in reducing force and tool wear,improving machining quality and machining *** machined surface integrity was discussed,the influence of process parameters on the machined surface quality was analyzed,and the machining defects of FRCMCs-SiC were *** for FRCMCs-SiC,the existing quantitative evaluation of the machined surface integrity was weak and unsystematic.

关键词： Ceramic matrix composites Machining Material removal mechanisms Quality Surface integrity

Model Averaging Estimation for Varying-Coefficient Single-Index Models

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Journal of Systems Science & Complexity 2022年第1期35卷 264-282页

作者： LIU Yue ZOU Jiahui ZHAO Shangwei YANG qinglong School of Statistics Jiangxi University of Finance and EconomicsNanchang 330013China. School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049China Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100190China. School of Science Minzu University of ChinaBeijing 100081China School of Statistics and Mathematics Zhongnan University of Economics and LawWuhan 430073China

The varying-coefficient single-index model(VCSIM)is widely used in economics,statistics and biology.A model averaging method for VCSIM based on a Mallows-type criterion is proposed to improve prodictive capacity,which allows the number of candidate models to diverge with sample *** model misspecification,the asymptotic optimality is derived in the sense of achieving the lowest possible squared *** authors compare the proposed model averaging method with several other classical model selection methods by simulations and the corresponding results show that the model averaging estimation has a outstanding *** authors also apply the method to a real dataset.

关键词： Asymptotic optimality kernel-local smoothing method Mallows-type criterion model averaging varying-coefficient single-index model

Bistatic weak target detection method using non-cooperative air surveillance radar

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Journal of Systems Engineering and Electronics 2015年第5期26卷 954-963页

作者： Dinghe Wang qinglong Bao Ruiqi Tian Zengping Chen Science and Technology on Automatic Target Recognition Laboratory National University of Defense Technology

At present, most of the passive radar system researches utilize FM radios, TV broadcasts, navigation satellites,etc. as illuminators. The transmitted signals are not specifically designed radar waveforms. In this work, the frequency agile, phased array air surveillance radar(ASR) is used as the illuminator of opportunity to detect the weak target. The phased array technology can help realize beam agility to track targets from different aspects simultaneously. The frequency agility technology is widely employed in radar system design to increase the ability of anti-jamming and increase the detection probability. While the frequency bandwidth of radar signals is usually wide and the range resolution is high, the range cell migration effect is obvious during the long time integration of non-cooperative bistatic radar. In this context, coherent integration methods are not applicable. In this work, a parametric non-coherent integration algorithm based on task de-interweaving is proposed. Numerical experiments verify that this is effective in weak target detection.

关键词： air surveillance radar non-cooperative bistatic task de-interweave

Long term integration of radar signals with unknown Doppler shift for ubiquitous radar

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Journal of Systems Engineering and Electronics 2011年第2期22卷 219-227页

作者： qinglong Bao Zengping Chen Yue Zhang Jian Yang ATR National Defense Science and Technology Key Lab National University of Defense Technology Changsha 410073 P. R. China

Ubiquitous radar is a new radar system that provides continuous and uninterrupted multifunction capability within a coverage volume. Continuous coverage from close-in ＂pop-up＂ targets in clutter to long-range targets impacts selection of waveform parameters. The coherent processing interval （CPI） must be long enough to achieve a certain signal-to-noise ratio （SNR） that ensures the efficiency of detection. The condition of detection in the case of low SNR is analyzed, and three different cases that would occur during integration are discussed and a method to determine the CPI is presented. The simulation results show that targets detection with SNR as low as -26 dB in the experimental system can possibly determine the CPI.

关键词： ubiquitous radar low signal-to-noise ratio (SNR),coherent processing interval (CPI) coherent integration non-coherent integration.

An integrated simulation system for operating solar sail spacecraft

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Journal of Systems Engineering and Electronics 2021年第5期32卷 1200-1211页

作者： ZHENG Yaru LI qinglong XU Ming DONG Yunfeng School of Astronautics Beihang UniversityBeijing 100191China

An integrated simulation system for solar sail spacecraft with individually controllable elements(SSICE)is investigated in this paper,including the modelling of power management,thermal control,attitude control,umbra prediction,and orbit prediction *** the self-control and reactivity subsystems,an agent based method is applied to develop the subsystem *** subsystem is an individual agent component,which manages itself autonomously and reacts to the requirements from other *** reduce computing burden on a specified computer and improve the suitability and flexibility of the integrated simulation system,a distributed framework is employed in the system by deploying agent components on different *** data transmission among agents is based on the transmission control protocol/Internet protocol(TCP/IP).A practical example of sun pointing is used to test the operating effect of the integrated system and the working condition of *** simulation results verify that the integrated system has higher sun pointing accuracy,quicker dynamical response to variations of the lighting,attitude and temperature and fewer computing resources with effective and accurate *** integrated system proposed in this paper can be applied to solar sail design,operation,and mission planning.

关键词： solar sail spacecraft integrated system agent distributed simulation individually controllable element

A class of transformation rate models for recurrent event data

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Science China Mathematics 2016年第11期59卷 2227-2244页

作者： ZHANG Hu YANG qinglong QU LianQiang School of Statistics and Mathematics Zhongnan University of Economics and Law Institute of Applied Mathematics Academy of Mathematics and Systems ScienceChinese Academy of Sciences

Recurrent event data frequently occur in longitudinal studies, and it is often of interest to estimate the effects of covariates on the recurrent event rate. This paper considers a class of semiparametric transformation rate models for recurrent event data, which uses an additive AMen model as its covariate dependent baseline. The new models are flexible in that they allow for both additive and multiplicative covariate effects, and some covariate effects are allowed to be nonparametric and time-varying. An estimating procedure is proposed for parameter estimation, and the resulting estimators are shown to be consistent and asymptotically normal. Simulation studies and a real data analysis demonstrate that the proposed method performs well and is appropriate for practical use.

关键词： Aalen model estimating equations recurrent event data time-varying coefficients transformation rate models

COORDINATION OF A FASHION AND TEXTILE SUPPLY CHAIN WITH DEMAND VARIATIONS

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Journal of Systems Science and Systems Engineering 2012年第4期21卷 461-479页

作者： Ke WANG qinglong GOU Jinwen SUN Xiaohang YUE School of Management University of Science and Technology of China Sheldon B.Lubar School of Business University of Wisconsin-MilwaukeeMilwaukeeWI 53201-0413USA

Owing to the changing fashion trends and a volatile market situation, demand in fashion and textile （FT） industry is unpredictable and could vary and change completely in a short time, which makes it more difficult to coordinate a FT supply chain. A change in product preference due to fashion trends is the main reason why the demand of FT industry shows more variations than other industries. In this paper, we use a well known contract, the all-unit quantity discount policy （AQDP）, to coordinate a FT supply chain with certain demand, and we further consider it under the demand variations scenario to investigate whether it can still coordinate the supply chain. In detail, before the selling season, an AQDP is provided by the manufacturer to the retailer, and under which the FT supply chain coordination achieved with a certain demand. During the selling season, demand variation is realized after an abrupt changing of fashion trends, therefore, the manufacturer may need to revise the original AQDP to insure the supply chain is still coordinated. Utilizing the mechanism design theory, we prove that：（i） while the traditional AQDP can coordinate the supply chain when no demand variations, it cannot always coordinate the supply chain after the demand variations; （ii） when the AQDP fails, we can use the proposed capacitated linear pricing policy （CLPP） to achieve a new coordination; （iii） a more dominant decision maker, who can set a higher profit goal, is favorable to stabilization of the supply chain system under demand variations. Numerical examples are proposed also to show our results.

关键词： Supply chain coordination fashion and textile industry market demand variation game theory