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Expression pattern and function analyses of the MADS thranscription factor genes in wheat(Triticum aestivum L.) under phosphorusstarvation condition

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Journal of Integrative Agriculture 2016年第8期15卷 1703-1715页

作者： SHI Shu-ya ZHANG fei-fei gao Si XIAO Kai Key Laboratory of Crop Growth Regulation of Hebei Province/College of Agronomy Agricultural University of Hebei

supported by the National Natural Science Foundation of China （31201674 and 31371618）;the National Transgenic Major Program, China （2011ZX08008）

关键词： wheat(Triticum aestivum L) MADS type transcription factor Pi deprivation expression gene function

Using approximate dynamic programming for multi-ESM scheduling to track ground moving targets

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Journal of Systems Engineering and Electronics 2018年第1期29卷 74-85页

作者： WAN Kaifang gao Xiaoguang LI Bo LI fei Key Laboratory of Aerospace Information Perception and Photoelectric Control Ministry of EducationSchool of Electronics and Information Northwestern Polytechnical University

This paper researches the adaptive scheduling problem of multiple electronic support measures(multi-ESM) in a ground moving radar targets tracking application. It is a sequential decision-making problem in uncertain environment. For adaptive selection of appropriate ESMs, we generalize an approximate dynamic programming(ADP) framework to the dynamic case. We define the environment model and agent model, respectively. To handle the partially observable challenge, we apply the unsented Kalman filter(UKF) algorithm for belief state estimation. To reduce the computational burden, a simulation-based approach rollout with a redesigned base policy is proposed to approximate the long-term cumulative reward. Meanwhile, Monte Carlo sampling is combined into the rollout to estimate the expectation of the rewards. The experiments indicate that our method outperforms other strategies due to its better performance in larger-scale problems.

关键词： sensor scheduling target tracking approximate dynamic programming non-myopic rollout belief state

Re-scaling and adaptive stochastic resonance as a tool for weak GNSS signal acquisition

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Journal of Systems Engineering and Electronics 2016年第2期27卷 290-296页

作者： Rongling Lang Xinyue Li fei gao Liang Yang School of Electronics and Information Engineering Beihang UniversityBeijing 100191China China United Network Communications Company Limited Tianjin 300052China

Weak global navigation satellite system（GNSS） signal acquisition has been a limitation for high sensitivity GPS receivers. This paper modifies the traditional acquisition algorithms and proposes a new weak GNSS signal acquisition method using re-scaling and adaptive stochastic resonance（SR）. The adoption of classical SR is limited to low-frequency and periodic signals. Given that GNSS signal frequency is high and that the periodic feature of the GNSS signal is affected by the Doppler frequency shift, classical SR methods cannot be directly used to acquire GNSS signals. Therefore, the re-scaling technique is used in our study to expand its usage to high-frequency signals and adaptive control technique is used to gradually determine the Doppler shift effect in GNSS signal buried in strong noises. The effectiveness of our proposed method was verified by the simulations on GPS L1 signals. The simulation results indicate that the new algorithm based on SR can reach-181 d BW sensitivity with a very short data length of 1 ms.

关键词： weak signal detection global navigation satellite system(GNSS) signal acquisition stochastic resonance

3D geological suitability evaluation for underground space based on the AHP-cloud model

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Underground Space 2023年第1期8卷 109-122页

作者： fei Deng jian Pu Yu Huang Qingding Han Department of Geotechnical Engineering College of Civil EngineeringTongji UniversityShanghai 200092China Key Laboratory of Geotechnical and Underground Engineering of the Ministry of Education Tongji UniversityShanghai 200092China Foshan Geological Bureau of Guangdong Province FoshanGuangdong 528000China

Urban development continues to reduce the amount of available ground *** development of underground space is thus gath-ering increasing attention to alleviate ground ***,there is currently a lack of a three-dimensional(3D)evaluation method to systematically evaluate the geological conditions of underground space and possible geological disaster risks caused by rock and soil *** paper presents an engineering geological suitability assessment framework based on 3D geological modeling and an analytic hierarchy process(AHP)-cloud *** the basis for 3D evaluation,a 3D structural model of the study area is established based on the drilling data and geological *** the structural model is partitioned to obtain interpolation grids,and the ordinary Kriging interpolation method is applied to attribute *** the attributes are exported from the geological model,and the rock and soil masses are divided into four categories according to their engineering properties,namely soft soil,sandy soil,cohesive soil,and rock,upon which a targeted hierarchy structure is established based on the attributes that impact the *** paper intro-duces the cloud model to characterize the uncertainty of these evaluation indexes,which synthesizes an AHP method,thus it is referred to as the AHP-cloud *** new model is used to evaluate the geological suitability of underground space in the Sanlong Bay district,Foshan City,Guangdong,*** addition,we also determine the excavation difficulty at different depths according to the lithology and weathering degree of the study *** limitations and future directions of the proposed method are discussed,including the influ-encing factors and weight determination.

关键词： 3D suitability evaluation Underground space Targeted AHP hierarchical structure Cloud model Difficulty of excavation

Method of moving target detection based on sub-image cancellation for single-antenna airborne synthetic aperture radar

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Journal of Systems Engineering and Electronics 2007年第3期18卷 448-453页

作者： Liu Shujun Yuan Yunneng gao fei Mao Shiyi Dept. of Electronic and Information Engineering Beihang Univ. Beijing 100083 P. R. China

The method of moving target detection based on subimage cancellation for single-antenna airborne SAR is presented. First the subimage is obtained through frequency processing is pointed out. The imaging difference of a stationary objects and moving object in the subimage based on the frequency division is analyzed from the fundamental principle. Then the developed method combines the shear averaging algorithm to focus on the moving target in the subimage, after the clutter suppression and the focusing position in each subimage is obtained. Next the observation model and the relative movement of the moving targets between the subimages estimate the moving targets. The theoretical analysis and simulation results demonstrate that the method is effective and can not only detect the moving targets, but also estimate their motion parameters precisely.

关键词： synthetic aperture radar moving target detection sub-image cancellation parameter estimation.

Pretreatment of Polymer-Supported Pd-Co and Its Catalytic Activity

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Chinese Chemical Letters 2000年第8期11卷 743-744页

作者： Yan gao Shi jian LIAO Fu Dong WANG Yue gao Xi gao jian Department of Polymer Science&Materials Dalian University of TechnologyDalian 116012 Dalian Institute of Chemical Physics The Chinese Academy of SciencesDalian 116023

Various pretreatments of poly (N-vinyl-2-pyrrolidone) (PVP) protected palladium-cobalt system result in different catalytic activities in the hydrodechlorination of chlorobenzene.

关键词： pretreatment polymer supported Pd-Co catalytic activity

A note on near-field site amplification effects of ground motion from a radially inhomogeneous valley

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Earthquake Engineering and Engineering Vibration 2018年第4期17卷 707-718页

作者： Zhang Ning gao Yufeng Wu Yongxin Zhang fei Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering Hohai University College of Civil and Transportation Engineering Hohai University

To improve the understanding of the near-field soil and topographic amplification effects, an analytical solution by the authors for the scattering of plane SH waves by a radially inhomogeneous semi-cylindrical valley is extended to the case of a line source of cylindrical SH waves. Upon confirmation of its accuracy with past exact solutions for a homogeneous and an inhomogeneous semi-cylindrical valley under far-field plane SH waves, the extended solution is used to calculate the ground motion amplification factors for both the homogeneous and inhomogeneous valleys subjected to near-field waves. A comprehensive parametric study is conducted with respect to the location of the wave source, the dimensionless frequency of the incident waves, and the inhomogeneity degree of the covering soil layer. It is found that more amplifications and reductions of ground motions will occur within a certain range in and around the valley as the sources are located further. Consistent with the far-field case, it is confirmed that an increase of the degree of inhomogeneity of the covering soil layer generally amplifies the ground motions significantly.

关键词： elastic SH-waves wave scattering and diffraction ground motion amplification valley canyon

Text Dimensionality Reduction with Mutual Information Preserving Mapping

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Chinese Journal of Electronics 2017年第5期26卷 919-925页

作者： YANG Zhen YAO fei FAN Kefeng HUANG jian College of Computer Science Beijing University of Technology Guangxi Colleges and Universities Key Laboratory of cloud computing and complex systems Guilin University of Electronic Technology China Electronics Standardization Institute Central University of Finance and Economics

With the explosion of information,it is becoming increasingly difficult to get what is really *** reduction is the first step in efficient processing of large *** dimensionality can be reduced in many ways,little work has been done to achieve dimensionality reduction without changing the inner semantic relationship among high dimension *** remedy this problem,we introduced a manifold learning based method,named Mutual information preserving mapping(MIPM),to explore the low-dimensional,neighborhood and mutual information preserving embeddings of highdimensional *** results show that the proposed method is effective for the text dimensionality reduction *** MIPM was used to develop a temporal summarization system for efficiently monitoring the information associated with an event over *** respect to the established baselines,results of these experiments show that our method is effective in the temporal summarization.

关键词： Dimensionality reduction Manifold learning Temporal summarization Mutual information preserving mapping(MIPM)

Geoscience Frontiers 2018 Annual Convention

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Geoscience Frontiers 2019年第2期10卷 787-788页

作者： fei gao Lily Wang Geoscience Frontiers Journal CenterChina University of Geosciences(Beijing)

The 2018 Geoscience Frontiers Annual Convention was held at the China University of Geosciences(Beijing),China,during September 20,2018(Fig.1).This convention assembled earth scientists from five countries,including Australia(*** Spencer),India(***),USA(*** Damian Nance and *** Meert),UK(*** Roberts),Turkey(*** Eyuboglu),China,and also representative from Elsevier(Beijing).

关键词： earth scientists