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Acta Metallurgica Sinica(English Letters) 2020年第7期33卷 1021-1030页

作者： Yun zi jie Meng Chaowei Zhang Yizhou Zhou Yutian Ding Institute of Metal Research Chinese Academy of SciencesShenyang 110016China Department of Materials Science and Engineering University of Science and Technology of ChinaHefei 230026China State Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals Lanzhou University of TechnologyLanzhou 730050China

A systematic study on the wettability and interactions between superalloy melts with various Re contents and Al2 O3-based ceramic moulds was presented in this *** was found that the increase of Re content inhibited the interfacial reactions to some *** regard to the 0,1.5 and 3 Re alloys,a double reaction layer containing Al2 O3 and HfO2 was formed at the interface,but the thickness of reaction layer decreased with the increase of Re ***,only Al2 O3 phase was detected at the interface when the content of Re was 6 wt%,and the interface reaction was the weakest and the thickness of reaction layer was the *** wetting angle of the alloy/ceramic system increased as the level of Re ***,the formation of viscous sand at the interface mainly depended on the change of wetting angle of the system.

关键词： superalloy alloy alloys

Analyzing Right-Censored Length-Biased Data with Additive Hazards Model

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Acta Mathematicae Applicatae Sinica 2017年第4期33卷 893-908页

作者： mu ZHAO Cun-jie LIN Yong ZHOU School of Statistics and Mathematics Zhongnan University of Economics and Law Wuhan 430073 China Center for Applied Statistics Renmin University of China Beijing 100872 China School of Statistics RenminUniversity of China Beijing 100872 China Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 China School of Statistics and Management Shanghai University of Finance and Economics Shanghai 200433 China

Length-biased data are often encountered in observational studies, when the survival times are left-truncated and right-censored and the truncation times follow a uniform distribution. In this article, we propose to analyze such data with the additive hazards model, which specifies that the hazard function is the sum of an arbitrary baseline hazard function and a regression function of covariates. We develop estimating equation approaches to estimate the regression parameters. The resultant estimators are shown to be consistent and asymptotically normal. Some simulation studies and a real data example are used to evaluate the finite sample properties of the proposed estimators.

关键词： additive hazards model length-biased data dependent censoring estimating equation

New lncRNA annotation reveals extensive functional divergence of the transcriptome in maize

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Journal of Integrative Plant Biology 2019年第4期61卷 394-405页

作者： Linqian Han Zhenna mu zi Luo Qingchun Pan Lin Li National Key Laboratory of Crop Genetic Improvement Huazhong Agricultural University

Long non-coding RNAs(lncRNAs), whose sequences are approximately 200 bp or longer and unlikely to encode proteins, may play an important role in eukaryotic gene regulation. Although the latest maize(Zea mays L.) reference genome provides an essential genomic resource, genome-wide annotations of maize lncRNAs have not been updated. Here, we report on a large transcriptomic dataset collected from 749 RNA sequencing experiments across different tissues and stages of the maize reference inbred B73 line and 60 from its wild relative teosinte. We identified 18,165 high-confidence lncRNAs in maize, of which 6,873 are conserved between maize and teosinte. We uncovered distinct genomic characteristics of conserved lncRNAs,non-conserved lncRNAs, and protein-coding ***, Shannon entropy analysis showed that conserved lncRNAs are likely to be expressed similarly to protein-coding transcripts. Co-expression network analysis revealed significant variation in the degree of co-expression. Furthermore, selection analysis indicated that conserved lncRNAs are more likely than non-conserved lncRNAs to be located in regions subject to recent selection, indicating evolutionary differentiation. Our results provide the latest genomewide annotation and analysis of maize lncRNAs and uncover potential functional divergence between proteincoding, conserved lncRNA, and non-conserved lncRNA genes, demonstrating the high complexity of the maize transcriptome.

关键词： lncRNA maize

Embedding pyridine units in acceptors to construct donor-acceptor conjugated polymers

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Chinese Chemical Letters 2019年第1期30卷 25-30页

作者： zi-Yuan Wang jie-Yu Wang Jian Pei Beijing National Laboratory for Molecular Sciences Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education Key Laboratory of Polymer Chemistry and Physics of Ministry of Education Center for Soft Matter Science and Engineering College of Chemistry and Molecular Engineering Peking University

The development of donor-acceptor(D-A) conjugated polymers greatly promotes the device performance in organic electronics. Recently, the strategy of embedding pyridine units into D-A conjugated polymer backbones has attracted much attention due to the resulted lowered LUMO levels. In addition, the possible non-bonding interactions resulted from the nitrogen atoms also improve the coplanarity of the polymer backbones. All these factors have great contribution to enhance the device performance. In this review, we summarized the recent development of pyridine-embedded D-A conjugated polymers and their applications in organic field-effect transistors(OFETs).

关键词： Donor-acceptor Conjugated polymers Coplanarity Pyridine-embedded Organic electronics

Galactic coordinate system based on multi-wavelength catalogs

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Research in Astronomy and Astrophysics 2015年第7期15卷 1045-1056页

作者： Ping-jie Ding zi Zhu Jia-Cheng Liu School of Astronomy and Space Science Nanjing University Key Laboratory of Modern Astronomy and Astrophysics (Nanjing University) Ministry of Education

The currently used Galactic coordinate system（GalC S） is based on the FK5 system at J2000.0, which was transformed from the FK4 system at *** limitations and misunderstandings related to this transformed GalC S can be avoided by defining a new GalC S that is directly connected to the International Celestial Reference System（ICRS）. With more data at various wavelengths released by large survey programs, a more appropriate GalC S consistent with features associated with the Milky Way can be established. We try to find the best orientation of the GalC S using data from two all-sky surveys, AKARI and WISE, at six wavelengths between 3.4 μm and 90 μm, and synthesize results obtained at various wavelengths to define an improved GalC S in the framework of the ICRS. The revised GalC S parameters for defining the new GalC S in the ICRS are summarized as：αp= 192.777°, δp= 26.9298°, for the equatorial coordinates of the north Galactic pole and θ = 122.95017° for the position angle of the Galactic center. As one of the Galactic substructures, the Galactic warp exhibits different forms in different GalC Ss that are constructed with various data and methods, which shows the importance of re-defining the GalC S by the relative commission of the International Astronomical Union that can lead to a better understanding of Galactic structure and kinematics.

关键词： astrometry -- catalogs -- Galaxy: general -- reference system

Elliptical distortion of the Milky Way＇s rotation traced by high-mass star-forming regions

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Research in Astronomy and Astrophysics 2017年第11期17卷 85-94页

作者： Ping-jie Ding zi Zhu Jia-Cheng Liu School of Astronomy and Space Science Nanjing University Nanjing 210023 China Key Laboratory of Modern Astronomy and Astrophysics (Nanjing University) Ministry of Education Nanjing 210023 China

The gravitational potential of the Milky Way is non-axisymmetric, caused by a bar or triaxial halo, which dominates elliptical rotation of the Milky Way. Employing a likelihood analysis, we exploit the astrometric data of masers thoroughly and constrain the elliptical rotation of the Galaxy. Masers in high-mass star-forming regions, observed by VLBA, are more distant tracers than stars observed in the optical bandpass, and thus are more appropriate for studying the global feature of the Milky Way＇s rotation. A clear elliptical potential of the Milky Way is detected, with an ellipticity of ε0-0.09 at the Sun, and the ellipticity increases towards the outer disk. The minor axis of the elliptical potential （the major axis of the rotation orbit） is found to be near the Sun with a displacement of -32°. Based on the rotation model assumed for an elliptical potential, we also make a kinematical calibration of the Galactocentric distance of the Sun, which gives R0 = 7.63±0.34 kpc.

关键词： astrometry -- Galaxy: fundamental parameters -- Galaxy: kinematics and dynamics --methods: data analysis

Identity-Based Encryption with Keyword Search from Lattice Assumption

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China Communications 2018年第4期15卷 164-178页

作者： Xiaojun Zhang Chunxiang Xu Liming mu jie Zhao School of Computer Science Southwest Petroleum UniversityChengdu 610500China School of Computer Science and Engineering University of Electronic Science and Technology of ChinaChengdu 611731China

Public key encryption scheme with keyword search （PEKS） enables us to search the encrypted data in a cloud server with a keyword, and no one can obtain any infor- mation about the encrypted data without the trapdoor corresponding to the keyword. The PEKS is useful to keep the management of large data storages secure such as those in a cloud. In this paper, to protect against quantum computer attacks, we present a lattice-based identity-based encryption scheme with key- word search. We have proved that our scheme can achieve ciphertext indistinguishability in the random oracle model, and our scheme can also achieve trapdoor security. In particular, our scheme can designate a unique tester to test and return the search results, therefore it does not need a secure channel. To the best of our knowledge, our scheme is the first iden- tity-based encryption scheme with keyword search from lattice assumption.

关键词： public key encryption keywordsearch ciphertext indistinguishability latticeassumption.

Local standard of rest based on Gaia DR2 catalog

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Research in Astronomy and Astrophysics 2019年第5期19卷 53-60页

作者： Ping-jie Ding zi Zhu Jia-Cheng Liu School of Astronomy and Space Science Nanjing University Key Laboratory of Modern Astronomy and Astrophysics Ministry of Education

The local standard of rest(LSR) provides a reference framework for studies of Galactic kinematics. Determination of the LSR corresponds to the measurement of solar peculiar motion, which is under debate due to the fact that different methods and samples have been used. Adopting the astrometric data and line-of-sight velocities of main sequence stars from Gaia DR2, we present a detailed analytical study of stellar kinematics in the solar neighborhood. Based on an improved version of the Stromberg relation, we obtain a robust estimation of the solar peculiar motion, which is given by(U☉,V☉,W☉)=(8.63 ± 0.64, 4.76 ± 0.49, 7.26 ± 0.36) km s^(-1). The corresponding radial scalelength is yielded as Rd ～ 2.5 kpc. The radial and vertical components of solar peculiar motion are basically consistent with the classical values, while the tangential component is a few km s^(-1) smaller than most estimates in literature.

关键词： astrometry Galaxy:fundamental parameters stars:kinematics and dynamics

Towards a better prediction of subcellular location of long non-coding RNA

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Frontiers of Computer Science 2022年第5期16卷 205-211页

作者： Zhao-Yue ZHANG zi-jie SUN Yu-He YANG Hao LIN Key Laboratory for NeuroInformation of Ministry of Education School of Life Science and Technology and Center for Informational BiologyUniversity of Electronic Science and Technology of ChinaChengdu 610054China

The spatial distribution pattern of long non-coding RNA(lncRNA)in cell is tightly related to their *** the increment of publicly available subcellular location data,a number of computational methods have been developed for the recognition of the subcellular localization of ***,these computational methods suffer from the low discriminative power of redundant features or overfitting of *** address those issues and enhance the prediction performance,we present a support vector machine-based approach by incorporating mutual information algorithm and incremental feature selection *** a result,the new predictor could achieve the overall accuracy of 91.60%.The highly automated web-tool is available at ***/server/iLoc-LncRNA(2.0)/*** will help to get the knowledge of lncRNA subcellular localization.

关键词： lncRNA subcellular localization support vector machine mutual information Web server

Image-based 3D model retrieval using manifold learning

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Frontiers of Information Technology & Electronic Engineering 2018年第11期19卷 1397-1408页

作者： Pan-pan mu San-yuan ZHANG Yin ZHANG Xiu-zi YE Xiang PAN College of Computer Science and Technology Zhejiang University College of Mathematics and Information Science Wenzhou University College of Computer Science and Technology Zhejiang University of Technology

We propose a new framework for image-based three-dimensional(3D) model retrieval. We first model the query image as a Euclidean point. Then we model all projected views of a 3D model as a symmetric positive definite(SPD) matrix, which is a point on a Riemannian manifold. Thus, the image-based 3D model retrieval is reduced to a problem of Euclid-to-Riemann metric learning. To solve this heterogeneous matching problem, we map the Euclidean space and SPD Riemannian manifold to the same high-dimensional Hilbert space, thus shrinking the great gap between them. Finally, we design an optimization algorithm to learn a metric in this Hilbert space using a kernel trick. Any new image descriptors, such as the features from deep learning, can be easily embedded in our framework. Experimental results show the advantages of our approach over the state-of-the-art methods for image-based 3D model retrieval.

关键词： Model retrieval Euclidean space Riemannian manifold Hilbert space Metric learning