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Development and prospects of garnet ceramic scintillators:A review

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Journal of Advanced Ceramics 2022年第12期11卷 1825-1848页

作者： Danyang ZHU Martin NIKL Weerapong CHEWPRADITKUL jiang LI Key Laboratory of Transparent Opto-functional Inorganic Materials Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 201899China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Institute of Physics The Czech Academy of SciencesPrague 16200Czech Republic Department of Physics King Mongkut’s University of Technology ThonburiBangkok 10140Thailand

Garnet ceramic scintillators are a class of inorganic scintillation materials with excellent overall *** flexibility of cation substitution in different lattice positions leads to tunable and versatile properties and a wide range of *** paper starts with an overview of the development history of the inorganic scintillation materials,followed by a description of major preparation methods and characterization of garnet scintillation *** progress obtained in recent years consisting in applying the band-gap and defect engineering strategies to the garnet scintillation ceramics is ***,the respective problems in the preparation and performance of multicomponent garnet single crystals and ceramics and the effective solutions are *** garnet scintillation ceramics with the highest application potential are summarized,and the future development directions are proposed.

关键词： garnet ceramics inorganic scintillators single crystals scintillation performance

A Sequential Converted Measurement Kalman Filter with Doppler Measurements in ECEF Coordinate System

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Chinese Journal of Electronics 2016年第1期25卷 139-145页

作者： WU Weihua jiang Jing FENG Xun QIN Xing Air Force Early Warning Academy

When there is the correlation between Doppler and slant range, previous literatures have presented some sequential filter algorithms. However, they are only applied to simplified fixed radar’ s local coordinate system. As a result, a Sequential converted measurement Kalman filter(SCMKF) with Doppler measurements based on the Earth centered earth fixed(ECEF) coordinate system applicable to a moving airborne platform which has time varying attitude is proposed. Firstly, the correlated Doppler and range are decorrelated using the Cholesky factorization, then the converted position measurements are obtained by a series of coordinate transformation with unchanged range component and other observations, such as azimuth and elevation angles; the corresponding error covariances are derived which are used to the Converted measurement Kalman filter(CMKF).Finally the sequential filter is implemented for changed pseudo-Doppler measurements. The proposed method is validated through Monte Carlo test compared with the performance of CMKF with just converted position measurements and traditional SCMKF with Doppler which ignores the correlation between Doppler and range noises,and the conclusion is obtained that utilizing Doppler information correctly can improve tracking performance, nevertheless, the improvement gain of filter accuracy is limited,which can provide some references for engineering application.

关键词： Target tracking Sequential filter Range rate Pseudo-Doppler measurements Earth centered earth fixed(ECEF) coordinate system Converted measurement Kalman filter(CMKF) Correlation coefficient

Influence of isothermal bainitic processing on the mechanical properties and microstructure characterization of TRIP steel

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Journal of University of Science and Technology Beijing 2008年第5期15卷 574-579页

作者： Haitao jiang Hubin Wu Di Tang Qiang Liu National Engineering Research Center for Advanced Rolling Technology University of Science and Technology Beijing Beijing 100083 China

The mechanical properties of transformation induced plasticity （TRIP） steel are strongly affected by the conditions of iso-thermal bainitic processing. The multiphase microstructure of TRIP steel under different conditions of isothermal bainitic processing was investigated using OM,SEM,XRD and TEM. The volume fraction of retained austenite and the carbon content in austenite were determined quantitatively using X-ray diffraction patterns. The relationship between mechanical properties and isothermal bainitic processing parameters was investigated. The stability of retained austenite was analyzed by the volume fraction of retained austenite and the carbon content in retained austenite. The experimental results show that the multiphase microstructure consists of ferrite,bainite and metastable retained *** obtain good mechanical properties,the optimal conditions of isothermal bainitic temperature and holding time are 410-430°C and 180-240 s,respectively. After isothermal bainitic processing under the optimal conditions,the corresponding volume fraction of retained austenite is 5vol%-15vol%,which can provide enough retained austenite and plastic stability for austenite with high carbon content.

关键词： transformation induced plasticity steel isothermal bainitic processing mechanical properties microstructure

Effects of heat treatment and Re-content on the TCP-phase in two Ni-Mo-Cr-Re superalloys

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Acta Metallurgica Sinica(English Letters) 2009年第5期22卷 365-372页

作者： Pingli MAO Yan XIN Ke HAN Weiguo jiang School of Materials Science and Engineering Shenyang Univers-ity of Technology Shenyang 110023 China National High Magnetic Field Laboratory Florida State University Tallahassee Florida USA Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

The volume fraction and morphology of the TCP-phase formed in two kinds of Ni- Mo-Cr-Re superalloys under different heat treatment conditions were investigated in this paper. In Re-5% alloy, with increasing of the heat treatment temperature and prolonging the holding time, the volume fraction of TCP-phase decreased and the TCP-phase size increased. At relatively lower temperature, the TCP-phase prefers to present in the dendrite cores. In Re-10% alloy, the volume fraction and size have the same change tendency as that of in Re-5% alloy, but the morphology will change from needle-like and block-like to sphere when the temperature increases. The TCP-phases formed in these two Ni-Mo-Cr-Re alloys are σ and P phase.

关键词： Heat treatment TCP-phase Superalloy

DISCOVERING NON-TERMINATING INPUTS FOR MULTI-PATH POLYNOMIAL PROGRAMS

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Journal of Systems Science & Complexity 2014年第6期27卷 1286-1304页

作者： LIU jiang XU Ming ZHAN Naijun ZHAO Hengjun Chongqing Key Laboratory of Automated Reasoning and Cognition CIGITChinese Academy of Sciences Department of Computer Science and Technology East China Normal University State Key Laboratory of Computer Science Institute of SoftwareChinese Academy of Sciences

This paper investigates the termination problems of multi-path polynomial programs （MPPs） with equational loop guards. To establish sufficient conditions for termination and nontermination simultaneously, the authors propose the notion of strong/weak non-termination which under/over- approximates non-termination. Based on polynomial ideal theory, the authors show that the set of all strong non-terminating inputs （SNTI） and weak non-terminating inputs （WNTI） both correspond to tile real varieties of certain polynomial ideals. Furthermore, the authors prove that the variety of SNTI is computable, and under some sufficient conditions the variety of WNTI is also computable. Then by checking the computed SNTI and WNTI varieties in parallel, termination properties of a consid- ered MPP can be asserted. As a consequence, the authors establish a new framework for termination analysis of MPPs.

关键词： Polynomial ideals polynomial programs termination analysis.

Physiological responses and detoxific mechanisms to Pb,Zn,Cu and Cd in young seedlings of Paulownia fortunei

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Journal of Environmental Sciences 2010年第12期22卷 1916-1922页

作者： jiang Wang Weihua Li Chongbang Zhang Shisheng Ke School of Life Sciences Taizhou University Linhai 317000 China Key Laboratory of Ecology and Environmental Science in Guangdong Higher Education College of Life Sciences South China Normal University Guangzhou 510631 China

Paulownia fortunei has been successfully used in the phytoremediation of many Pb/Zn mine tailings. However, seed germination and young seedlings of P. fortunei rarely occurred in these mine tailings. The physiological responses and detoxific mechanisms of P. fortunei young seedling to Pb, Zn, Cu and Cd stress were investigated. The germinated rate, shoot length, chlorophyll and carotenoid contents in leaves of young seedlings had a great reduction under Zn and Cu treatments, but had little decrease under Pb and Cd treatments. The production rate of O2＊-, H2O2 and malondialdehyde （MDA） contents significantly increased in response to added Zn and Cu indicating great oxidative stress for young seedlings, but they had no significant change to added Pb and Cd. Young seedlings had effective detoxific mechanism to Pb and Cd, as antioxidant enzymes activities, phytochelatins （PCs-SH） and proline contents increased with increasing rates of added Pb and Cd. However, young seedlings had un-effective detoxific mechanisms to Zn and Cu stress. Results revealed the heavy metals （such as Ca） that present at low concentrations in mine tailings may be major constraint for the survival of young seedlings.

关键词： heavy metals defense system oxygen species antioxidant enzyme phytochelatins

DOA estimation and mutual coupling calibration with the SAGE algorithm

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Chinese Journal of Aeronautics 2014年第6期27卷 1538-1543页

作者： Xiong Kunlai Liu Zhangmeng Liu Zheng jiang Wenli College of Electronic Science and Engineering National University of Defense Technology

In this paper, a novel algorithm is presented for direction of arrival（DOA） estimation and array self-calibration in the presence of unknown mutual coupling. In order to highlight the relationship between the array output and mutual coupling coefficients, we present a novel model of the array output with the unknown mutual coupling coefficients. Based on this model, we use the space alternating generalized expectation-maximization（SAGE） algorithm to jointly estimate the DOA parameters and the mutual coupling coefficients. Unlike many existing counterparts, our method requires neither calibration sources nor initial calibration information. At the same time,our proposed method inherits the characteristics of good convergence and high estimation precision of the SAGE algorithm. By numerical experiments we demonstrate that our proposed method outperforms the existing method for DOA estimation and mutual coupling calibration.

关键词： Array self-calibration Convergence Direction of arrival estima-tion Mutual coupling Space alternating generalized expectation-maximization algorithm

Analytical Compliance Modeling of Serial Flexure-Based Compliant Mechanism Under Arbitrary Applied Load

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Chinese Journal of Mechanical Engineering 2017年第4期30卷 951-962页

作者： Li-Ping Wang Yao jiang Tie-Min Li Institute of Manufacturing Engineering Department of MechanicalTsinghua UniversityBeijing 100084China Beijing Key Laboratory of Precision/Ultra-Precision Manufacturing Equipments and Control Tsinghua UniversityBeijing 100084China Institute of Instrument Science and Technology Department of Precision InstrumentTsinghua UniversityBeijing 100084China

Analytical compliance model is vital to the flexure- based compliant mechanism in its mechanical design and motion control. The matrix is a common and effective approach in the compliance modeling while it is not well developed for the closed-loop serial and parallel compliant mechanisms and is not applicable to the situation when the external loads are applied on the flexure mem- bers. Concise and explicit analytical compliance models of the serial flexure-based compliant mechanisms under arbitrary loads are derived by using the matrix method. An equivalent method is proposed to deal with the situation when the external loads are applied on the flexure mem- bers. The external loads are transformed to concentrated forces applied on the rigid links, which satisfy the equa- tions of static equilibrium and also guarantee that the deformations at the displacement output point remain unchanged. Then the matrix method can be still adopted for the compliance analysis of the compliant mechanism. Finally, several specific examples and an experimental testare given to verify the effectiveness of the compliance models and the force equivalent method. The research enriches the matrix method and provides concise analytical compliance models for the serial compliant mechanism.

关键词： Compliant mechanism Compliancemodeling Matrix method

A Bayesian Recommender Model for User Rating and Review Profiling

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Tsinghua Science and Technology 2015年第6期20卷 634-643页

作者： Mingming jiang Dandan Song Lejian Liao Feida Zhu School of Computer Science and Technology Beijing Institute of Technology School of Information Systems Singapore Management University

Intuitively, not only do ratings include abundant information for learning user preferences, but also reviews accompanied by ratings. However, most existing recommender systems take rating scores for granted and discard the wealth of information in accompanying reviews. In this paper, in order to exploit user profiles’ information embedded in both ratings and reviews exhaustively, we propose a Bayesian model that links a traditional Collaborative Filtering(CF) technique with a topic model seamlessly. By employing a topic model with the review text and aligning user review topics with 'user attitudes'(i.e., abstract rating patterns) over the same distribution, our method achieves greater accuracy than the traditional approach on the rating prediction task. Moreover, with review text information involved, latent user rating attitudes are interpretable and 'cold-start' problem can be *** property qualifies our method for serving as a 'recommender' task with very sparse datasets. Furthermore,unlike most related works, we treat each review as a document, not all reviews of each user or item together as one document, to fully exploit the reviews’ information. Experimental results on 25 real-world datasets demonstrate the superiority of our model over state-of-the-art methods.

关键词： collaborative filtering topic model recommender sy