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Acta Metallurgica Sinica(English Letters) 2019年第2期32卷 263-268页

作者： Fang-Wei Jiao Li jin jie Dong Feng-Hua Wang National Engineering Research Center of Light Alloys Net Forming School of Material Sciences and Engineering Shanghai Jiaotong University

Previous studies showed that signifi cant increases in elongation in Mg–Ce alloys due to the Ce addition and the solute drag eff ect by Ce addition were ascribed to the non-basal dislocation slip activating and the texture altering. The microstructure evolution and deformation models of extruded Mg-0.5 wt%Ce alloy rods under uniaxial tension have been studied using in situ electron backscatter diff raction. The basal and non-basal slips were characterized by using slip line trace analysis. The results provide evidence for that pyramidal slip activated during deformation, besides basal slip and extension twinning, which contributes to the texture weakening and ductility increasing in Mg-0.5 wt%Ce alloy.

关键词： Texture Non-basal slip Twinning In situ electron backscattered diff raction(EBSD) Trace analysis

Assessing site investigation program for design of shield tunnels

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Underground Space 2023年第2期9卷 31-42页

作者： jie Zhang Yuan Sun jin-zheng Hu Hong-wei Huang Department of Geotechnical Engineering Tongji UniversityShanghai 200092China Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education Tongji UniversityShanghai 200092China

In the design of shield tunnels,it is expected that a design can be more economical as more site investigation data are ***-ertheless,the cost of site investigation will also increase as more site investigation data are *** is thus important to assess the potential benefit of a site investigation program before it is conducted considering the uncertainty in the soil properties and the site inves-tigation *** this paper,a probabilistic framework is suggested to assess the effectiveness of a site investigation program for the design of shield tunnels through the random field *** efficient method based on the generalized extreme value distribution is used to calculate the failure probability of the tunnel,through which the expected benefit from a site investigation program can be estimated *** result shows that a site investigation program is more valuable when a greater target design reliability index is *** expected benefit from a site investigation program increases as the borehole intensity increases,and it also increases as the scale of fluctuation of the soil properties *** method suggested in this paper provides a useful tool for planning borehole layout for the design of shield tunnels,which is promising for the optimization of site investigation.

关键词： Shied tunnel Site investigation Uncertainty Spatial variability

Porous a-Al_2O_3 thermal barrier coatings with dispersed Pt particles prepared by cathode plasma electrolytic deposition

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International Journal of Minerals,Metallurgy and Materials 2016年第1期23卷 92-101页

作者： Peng Wang Ye-dong He Shun-jie Deng jin Zhang Beijing Key Laboratory for Corrosion Erosion and Surface Technology University of Science and Technology Beijing

Porous α-Al2O3 thermal barrier coatings （TBCs） containing dispersed Pt particles were prepared by cathode plasma electrolytic deposition （CPED）. The influence of the Pt particles on the microstructure of the coatings and the CPED process were studied. The prepared coatings were mainly composed of α-Al2O3. The average thickness of the coatings was approximately 100 μm. Such single-layer TBCs ex- hibited not only excellent high-temperature cyclic oxidation and spallation resistance, but also good thermal insulation properties. Porous α-Al2O3 TBCs inhibit further oxidation of alloy substrates because of their extremely low oxygen diffusion rate, provide good thermal insu- lation because of their porous structure, and exhibit excellent mechanical properties because of the toughening effect of the Pt particles and because of stress relaxation induced by deformation of the porous structure.

关键词： porous material thermal barrier coatings alumina platinum electrolytic deposition oxidation

A Bregman-style Partially Symmetric Alternating Direction Method of Multipliers for Nonconvex Multi-block Optimization

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Acta Mathematicae Applicatae Sinica 2023年第2期39卷 354-380页

作者： Peng-jie LIU jin-bao JIAN Guo-dong MA School of Mathematics China University of Mining and TechnologyXuzhou 221116China College of Mathematics and Physics Center for Applied Mathematics of GuangxiGuangxi Minzu UniversityNanning 530006China

The alternating direction method of multipliers(ADMM)is one of the most successful and powerful methods for separable minimization *** on the idea of symmetric ADMM in two-block optimization,we add an updating formula for the Lagrange multiplier without restricting its position for multiblock ***,combining with the Bregman distance,in this work,a Bregman-style partially symmetric ADMM is presented for nonconvex multi-block optimization with linear constraints,and the Lagrange multiplier is updated twice with different relaxation factors in the iteration *** the suitable conditions,the global convergence,strong convergence and convergence rate of the presented method are analyzed and ***,some preliminary numerical results are reported to support the correctness of the theoretical assertions,and these show that the presented method is numerically effective.

关键词： nonconvex optimization multi-block optimization alternating direction method with multipliers Kurdyka-Lojasiewicz property convergence rate

Fault diagnosis and isolation of the componentand sensor for aircraft engine

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航空动力学报 2012年第6期27卷 1432-1440页

作者： QIU Xiao-jie HUANG jin-quan LU Feng LIU Nan College of Energy and Power Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

Aircraft engine component and sensor fault detection and isolation approach was proposed,which included fault type detection module and component-sensor simultaneous fault isolation *** approach can not only distinguish among sensor fault,component fault and component-sensor simultaneous fault,but also isolate and locate sensor fault and the type of engine component fault when the engine component fault and the sensor faults occur *** double-threshold mechanism has been proposed,in which the fault diagnostic threshold changed with the sensor type and the engine condition,and it greatly improved the accuracy and robustness of sensor fault diagnosis *** results show that the approach proposed can diagnose and isolate the sensor and engine component fault with improved *** effectively improves the fault diagnosis ability of aircraft engine.

关键词： aircraft engine sensor fault engine component fault simultaneous fault diagnosis isolation double-threshold mechanism

Research on Electronic Document Management System Based on Cloud Computing

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Computers, Materials & Continua 2021年第3期66卷 2645-2654页

作者： jin Han Cheng Wang jie Miao Mingxin Lu Yingchun Wang jin Shi Nanjing University of Information Science&Technology Nanjing210044 China 2Research Institute of State Grid Hunan Electric Power Company LimitedChangsha410007 China 3Nanjing UniversityNanjing210093 China 4Waterford Institute of TechnologyWaterford CityX91 K0EKIreland

With the development of information technology,cloud computing technology has brought many conveniences to all aspects of work and *** the continuous promotion,popularization and vigorous development of e-government and e-commerce,the number of documents in electronic form is getting larger and *** document is an indispensable main tool and real record of e-government and business *** to scientifically and effectively manage electronic documents?This is an important issue faced by governments and enterprises in improving management efficiency,protecting state secrets or business secrets,and reducing management *** paper discusses the application of cloud computing technology in the construction of electronic file management system,proposes an architecture of electronic file management system based on cloud computing,and makes a more detailed discussion on key technologies and *** electronic file management system is built on the cloud architecture to enable users to upload,download,share,set security roles,audit,and retrieve files based on multiple *** electronic file management system based on cloud computing can make full use of cloud storage,cloud security,and cloud computing technologies to achieve unified,reliable,and secure management of electronic files.

关键词： Cloud computing technology electronic file management system cloud security

New Vacuum Solar Telescope Achieves Narrowband Infrared Solar Imaging Observation at He I 10830 A

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Research in Astronomy and Astrophysics 2024年第5期24卷 76-84页

作者： Wei-jie Meng Fang-Yu Xu Zhen-Yu jin Yunnan Observatories Chinese Academy of SciencesKunming 650011China Yunnan Key Laboratory of Solar Physics and Space Science Kunming 650216China University of Chinese Academy of Sciences Beijing 100049China

The near-infrared imaging channel constitutes a crucial component of the multichannel high-resolution imaging system of the New Vacuum Solar Telescope(NVST). We have successfully achieved high-resolution, narrowband imaging of the chromosphere using He I 10830 A triplet within this channel, which significantly enhances the imaging observation capabilities of NVST. This paper provides a concise overview of the optical system associated with the near-infrared imaging channel, detailing data processing procedures and presenting several observed images. Leveraging a high-resolution image reconstruction algorithm, we were able to generate a narrowband image near the diffraction limit at 10830 A with a temporal resolution of less than 10 s.

关键词： instrumentation detectors-instrumentation high angular resolution-Sun chromosphere-Sun infrared

Comprehensive Parameter for Analyzing Condensation in Pneumatic System

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Chinese Journal of Mechanical Engineering 2010年第5期23卷 641-646页

作者： jin Yingzi LI Yi WANG Yanping WANG jie ZHU Zuchao Zhejiang Province Key Laboratory of Textile Machinery Zhejiang Sci- Tech University Hangzhou 310018 China The State Key Lab of Fluid Power Transmission and Control Zhejiang University Hangzhou 310027 China

The condensation in pneumatic system is a complex physical phenomenon dependant upon status variation and phase transitions,which are related to the parameters of the compressed air,atmospheric conditions and the dimensions of the pneumatic *** to now,general research method for this problem is to calculate the status variation and movement quantity by numerical simulation and experiment *** comprehensive parameters composed of several different effect factors are rarely used to study the *** composed components and the working conditions of each cylinder are different,a large number of experiments and complex calculations are necessary to determine the ***,the transferability of the determined results is *** this paper,the charging and discharging systems of serials cylinder with different structure parameters are *** condensation of the systems is observed and the effects of the structure parameters on condensation are *** changing trends of relative humidity,natural frequency and average speed against the structural parameters of the components during discharge of the pneumatic systems are *** comprehensive parameters used to analyze and determine condensation composed by structure parameters of components are proposed,namely,the ratio of the effective area of the discharge tube and the container volume,the square root of the effective area of the discharge tube divided by the product of the container volume and the length of the discharge tube,and the discharge dimensionless *** experimental results show that these comprehensive parameters can be used to quantitatively determine whether internal,external or zero condensation occurs in a pneumatic system,and can be also used to quantitatively analyze the experimental data of condensation in pneumatic systems *** the same time,the effect factors are too much and the effect relationships are very complex,which

关键词： pneumatic system condensation comprehensive parameter structure parameter

Optimal precoding for full-duplex base stations under strongly correlated self-interference channels

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Frontiers of Information Technology & Electronic Engineering 2017年第6期18卷 808-816页

作者： Jun WANG Xiao-jie WEN Chuan HUANG Chao-jin QING College of Electrical and Information Engineering Southwest University for NationalitiesChengdu 610041China Beijing Institute of Satellite Information Engineering Beijing 100086China National Key Laboratory of Science and Technology on Communications University of Electronic Science and Technology of ChinaChengdu 611731China School of Electrical and Information Engineering Xihua UniversityChengdu 610039China

We study the optimal precoding for a full-duplex (FD) system, where one FD multi-antenna base station (BS) respectively transmits to and receives from two half-duplex single-antenna mobile users (MUs) on the same time slot and frequency band. At the FD BS, the received signal from the desired MU is severely affected by the extremely strong self-interference (SI) from its transmit antennas to the receive antennas. In the presence of residual SI after imperfect SI cancellation, the downlink transmission rate maximization problem subject to a targeted uplink rate is formulated as a non-convex optimization problem to characterize the achievable rate region for the considered system. Considering the case in which the SI channel is strongly correlated, the above problem is transformed into a convex problem by exploiting the rank-one property of the SI channel, which can be solved efficiently. Finally, numerical results validate the effectiveness of the proposed scheme.

关键词： Linear precoding Full-duplex Achievable rate region Strongly correlated self-interference channel

Surface recrystallization of a single crystal nickel-base superalloy

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International Journal of Minerals,Metallurgy and Materials 2011年第2期18卷 197-202页

作者： jie Meng Tao jin Xiao-feng Sun Zhuang-qi Hu Department of Superalloys Institutes of Metal Research Chinese Academy of Sciences Shenyang Beijing 110016 China State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing 100083 China

The recrystallization behavior of a single crystal nickel-base superalloy was investigated by shot peening and subsequent annealing. Two kinds of recrystallization microstructures, which are intensively dependent on the annealing temperature, are shown in the nickel-base superalloy after shot peening and subsequent annealing. Surface recrystallized grains are obtained when the superalloy is annealed at solution treatment temperature. The nucleation of recrystallization originates from the dendritic core, where rapid dissolution of γ＇ particles occurs. Cellular recrystallization is observed after annealing at lower temperatures. Cellular structures induced by high diffusivity of the moving boundary and more γ＇ particles dissolution led by residual stress are developed from the surface region. Recrystallized kinetics of the shot-peened alloy annealed at 1050°C accords with the Johnson-Mehl-Avrami-Kolmogorov equation. The low Avrami exponent is caused by the inhomogeneous distribution of stored energy, the decreasing of stored energy during recovery, and the strong resistance of boundary migration by γ＇ particles.

关键词： nick-base superalloy single crystals recrystallization shot peening annealing