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Effects of the vegetation restoration years on soil microbial community composition and biomass in degraded lands in Changting County,China

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Journal of Forestry Research 2020年第4期31卷 1295-1308页

作者： Yonghui Bai Xuan zha Shifa Chen Key Laboratory for Subtropical Mountain Ecology(Ministry of Science and Technology and Fujian Province Funded) School of Geographical SciencesFujian Normal UniversityFuzhou 350007China College of Tourism and geography Shaoguan UniversityShaoguan 512005China

We evaluated the effects of the number of years of restoration of vegetation on soil microbial community structure and biomass in degraded *** investigated the microbial community structure by analyzing their phospholipid fatty acids then examined microbial biomass carbon and nitrogen by chloroform fumigation extraction of restoration soils over several *** data were compared with those of highly degraded lands and native vegetation *** results show that the duration of vegetation on the sites substantially increased microbial biomass and shifted the microbial community structure even after only 4 ***,microbial communities and biomass did not recover to the status of native vegetation even after 35 years of vegetation cover.A redundancy analysis and Pearson correlation analysis indicated that soil organic carbon,total nitrogen,available potassium,soil water content,silt content and soil hardness explained 98.4%of total variability in the microbial community *** organic carbon,total nitrogen,available potassium and soil water content were positively correlated with microbial community structure and biomass,whereas,soil hardness and silt content were negatively related to microbial community structure and *** study provides new insights into microbial community structure and biomass that influence organic carbon,nitrogen,phosphorus and potassium accumulation,and clay content in soils at different stages of restoration.

关键词： Vegetation restoration Soil microorganisms Environmental factors PLFA Degraded red soil lands

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Modeling method of sequence admittance for three-phase voltage source converter under unbalanced grid condition

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Journal of Modern Power Systems and Clean Energy 2018年第3期6卷 595-606页

作者： Yang CEN Meng HUANg Xiaoming zha School of Electrical Engineering Wuhan University

The admittance is a strong tool for stability analysis and assessment of the three-phase voltage source converters(VSCs) especially in grid-connected ***, the sequence admittance is hard to calculate when the VSC is operating under unbalanced grid voltage conditions. In this paper, a simple and direct modeling method is proposed for a three-phase VSC taking the unbalanced grid voltage as a new variable for the *** coupling in the three-phase system can be calculated by applying the harmonic linearization method. The calculated admittance of three-phase VSCs is verified by detailed circuit simulations.

关键词： Unbalanced grid voltage Three-phase voltage source converter Harmonic linearization Positive and negative sequence admittance Stability

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Optimizing scheme for probabilistic remote preparation of a two-qubit state

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The Journal of China Universities of Posts and Telecommunications 2013年第6期20卷 109-116页

作者： XIA Jia-fan zha Xin-wei School of Science Xi'an University of Posts and Telecommunications

Remote state preparation is increasingly becoming attractive in recent years, people have already started theoretical and experimental research, and have made valuable research results. Recently, a scheme for probabilistic remote preparation of a general two-qubit state was proposed （Wang z Y in Quantum Inf Process. 11：1585, 2012））. In this paper, we present a modified scheme for probabilistic remote preparation of a general two-qubit state. To complete the scheme, the new and feasible complete orthogonal basis vectors have been introduced. Compared with the previous schemes, the advantage of our schemes is that the total success probability of remote state preparation will be greatly improved. The probability of success regarding this scheme is calculated in both general and particular cases. The results show that the success probability of remote state preparation can be improved a little. However, in certain special cases, the success probability of preparation can be greatly improved. In special cases, the success probability of preparation can be improved to 1. The security analysis of the scheme is provided in details.

关键词： remote state preparation w-type state orthogonal basis vector success probability of preparation

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A curvelet-based method to determine wave directions from nautical X-band radar images

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Acta Oceanologica Sinica 2018年第1期37卷 11-19页

作者： zha guozhen HE Qingyou gUAN Changlong CHEN Jitao College of Oceanic and Atmospheric Sciences Ocean University of China Qingdao 266100 China Physical Oceanography Laboratory Ocean University of China Qingdao 266100 China State Key Laboratory of Tropical Oceanography South China Sea Institute of Oceanology Chinese Academy of Science Guangzhou 510301 China Hydrology Bureau of Yellow River Conservancy Commission Zhengzhou 450004 China

A new method to determine wave directions from nautical X-band images is proposed. The signatures of ocean waves show obvious scale and directional characteristics in nautical X-band radar images. Curvelet transform（CT） possesses very high scale and directional sensitivities. Therefore, it has good capability to analyze ocean wave fields. The radar images are decomposed at different scales, in different directions, and at different positions by CT, and curvelet coefficients are obtained. given to the scale and directional characteristics of surface waves,the information of ocean waves is centralized in the curvelet coefficients of certain directions and at certain ***, the wave orientations can be determined. The 180 ambiguity is removed by calculating crosscorrelation coefficients（CCCs） between continuous collected images. The proposed method is verified by the dataset collected on the Northwest coast of the zhangzi Island in the Yellow Sea of China from March to April 2009.

关键词： X-band radar wave direction surface wave curvelet transform

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CPg Control for Biped Hopping Robot in Unpredictable Environment

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Journal of Bionic Engineering 2012年第1期9卷 29-38页

作者： Tingting Wang Wei guo Mantian Li Fusheng zha Lining Sun State Key Laboratory of Robotics and System Harbin Institute of TechnologyHarbin 150080P.R.China

A CPg control mechanism is proposed for hopping motion control of biped robot in unpredictable environment. Based on analysis of robot motion and biological observation of animal＇s control mechanism, the motion control task is divided into two simple parts： motion sequence control and output force control. Inspired by a two-level CPg model, a two-level CPg control mechanism is constructed to coordinate the drivers of robot joint, while various feedback information are introduced into the control mechanism. Interneurons within the control mechanism are modeled to generate motion rhythm and pattern promptly for motion sequence control; motoneurons are modeled to control output forces of joint drivers in real time according to feedbacks. The control system can perceive changes caused by unknown perturbations and environment changes according to feedback information, and adapt to unpredictable environment by adjusting outputs of neurons. The control mechanism is applied to a biped hopping robot in unpredictable environment on simulation platform, and stable adaptive motions are obtained.

关键词： biped robot unpredictable environment hopping motion control bionic control CPg

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CirroData: Yet Another SQL-on-Hadoop Data Analytics Engine with High Performance

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Journal of Computer Science & Technology 2020年第1期35卷 194-208页

作者： zheng-Hao Jin Haiyang Shi Ying-Xin Hu Li zha Xiaoyi Lu Business-Intelligence of Oriental Nations Corporation Ltd. Beijing 100102China Department of Computer Science and Engineering The Ohio State UniversityOhio 43210U.S.A Institute of Computing Technology Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 101408China

This paper presents CirroData,a high-performance SQL-on-Hadoop system designed for Big Data analytics *** a home-grown enterprise-level online analytical processing(OLAP)system with more than seven-year research and development(R&D)experiences,we share our design details to the community about how to achieve high performance in *** optimization techniques have been discussed in the *** effectiveness and the efficiency of all these techniques have been proved by our customers'daily ***-level studies,as well as several real application case studies of CirroData,have been presented in this *** evaluations show that CirroData can outperform various types of counterpart database systems in the community,such as"Spark+Hive","Spark+HBase",Impala,DB-X/Y,greenplum,HAWQ,and *** can achieve up to 4.99x speedup compared with greenplum,HAWQ,and Spark in the standard TPC-H ***-level evaluations demonstrate that CirroData outperforms"Spark+Hive"and"Spark+HBase"by up to 8.4x and 38.8x,*** the meantime,CirroData achieves the performance speedups for some application workloads by up to 20x,100x,182.5x,92.6x,and 55.5x as compared with greenplum,DB-X,Impala,DB-Y,and HAWQ,respectively.

关键词： CirroData high performance SQL-on-Hadoop online analytical processing(OLAP) Big Data

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Microcellular Foaming of Plasticized Thin PC Sheet *** of Processing Conditions

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Journal of Wuhan University of Technology(Materials Science) 2013年第2期28卷 235-242页

作者：陈浩管蓉 zhaO Jingzuo JIANg Shufang KE zhao zha Shangwen Ministry of Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules College of Chemistry and Chemical Engineering Hubei University

Novel microcellular foams using thin plasticized PC sheet were prepared by compression molding. The measurement results showed that T of plasticized PC was decreased and the molecular chain mobility was increased. Decrease in T and increase in chains mobility were contributed to the widen of foaming temperature window. Effects of processing conditions on cell size, cell density and relative density were also investigated. The experimental results show that the temperature, tributyl citrate and foaming agent content have more effects on the structures and morphology of the plasticized PC microcellular foam. Effects of experimental conditions on cell size distribution have also been discussed.

关键词： plasticization microcellular foam polycarbonate compression molding

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Advances in biotechnological production of santalenes and santalols

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Chinese Herbal Medicines 2021年第1期13卷 90-97页

作者： Wen-long zha Jia-chen zi Biotechnological Institute of Chinese Materia Medica Jinan UniversityGuangzhou 510632China College of Pharmacy Jinan UniversityGuangzhou 510632China

Sandalwood essential oil has been widely used not only as natural medicines but also in perfumery and food industries, with sesquiterpenoids as its major components including(z)-a-santalol and(z)-bsantalol and so on. The mature heartwoods of Santalum album, Santalum austrocaledonicum and Santalum spicatum are the major plant resources for extracting sandalwood essential oil, which have been overexploited. Synthetic biology approaches have been successfully applied to produce natural products on large scale. In this review, we summarize biosynthetic enzymes of santalenes and santalols, including various santalene synthases(STSs) and cytochrome P450 monooxygenases(CYPs), and then highlight the advances of biotechnological production of santalenes and santalols in heterologous hosts, especially metabolic engineering strategies for constructing santalene-and santalol-producing Saccharomyces cerevisiae.

关键词： biosynthesis biotechnological production sandalwood oil santalenes santalols

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Space Charge Suppression of Polyethylene Induced by Blending with Ethylene-butyl Acrylate Copolymer

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CSEE Journal of Power and Energy Systems 2020年第1期6卷 152-159页

作者： Jintao zhai Weikang Li Junwei zha Qi Cheng Xingming Bian zhimin Dang School of Chemistry and Biological Engineering University of Science&Technology BeijingChina State Key Laboratory of Advanced Transmission Tech-nology Global Energy Interconnection Research InstituteBeijing 100083China State Key Laboratory of Alternate Electrical Power Sys-tem with Renewable Energy Sources North China Electric Power UniversityBeijing 102206China State Key Laboratory of Power System Department of Electrical EngineeringTsinghua UniversityBeijing 100084China

High-voltage direct current(HVDC)power cables have been paid more attention due to the big issue concerning the main insulation *** residues in the industrial production process will cause space charge generation and accumulation in the materials,which has become one bottleneck to limit the development of power cables up to higher voltage *** this paper,the LDPE matrix was modified by three types of ethylene-butyl acrylate(EBA)copolymers(1.0 wt%)with different polarities(BA content)via melt blending to optimize the space charge behavior of the LDPE *** micromorphology and structure of the blends are examined by polarized light microscope and differential scanning *** space charge distribution is tested by the pulsed electro-acoustic *** trap level is studied by the thermally stimulated *** results show that EBA introduces more deep traps and decreases the shallow *** medium-polar EBA(16%BA content)can effectively suppress charge accumula-tion,and have the same suppressed effect on XLPE/EBA *** study will provide important insights into the design and development of advanced HVDC power cable applications.

关键词： Cable Insulation dielectric materials polyethy-lene insulations space charge

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Squeezing More Past Knowledge for Online Class-Incremental Continual Learning

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IEEE/CAA Journal of Automatica Sinica 2023年第3期10卷 722-736页

作者： Da Yu Mingyi zhang Mantian Li Fusheng zha Junge zhang Lining Sun Kaiqi Huang the State Key Laboratory of Robotics and System Harbin Institute of Technology(HIT)Harbin 150080China Center for Research on Intelligent System and Engineering Institute of AutomationChinese Academy of Sciences(CASIA)Beijing 100190 School of Artificial Intelligence University of Chinese Academy of SciencesBeijing 100049China Center for Research on Intelligent System and Engineering Institute of AutomationChinese Academy of Sciences(CASIA)Beijing 100190the School of Artificial IntelligenceUniversity of Chinese Academy of SciencesBeijing 100049 the CAS Center for Excellence in Brain Science and Intelligence Technology Shanghai 200031China IEEE

Continual learning(CL)studies the problem of learning to accumulate knowledge over time from a stream of data.A crucial challenge is that neural networks suffer from performance degradation on previously seen data,known as catastrophic forgetting,due to allowing parameter *** this work,we consider a more practical online class-incremental CL setting,where the model learns new samples in an online manner and may continuously experience new ***,prior knowledge is unavailable during training and *** works usually explore sample usages from a single dimension,which ignores a lot of valuable supervisory *** better tackle the setting,we propose a novel replay-based CL method,which leverages multi-level representations produced by the intermediate process of training samples for replay and strengthens supervision to consolidate previous ***,besides the previous raw samples,we store the corresponding logits and features in the ***,to imitate the prediction of the past model,we construct extra constraints by leveraging multi-level information stored in the *** the same number of samples for replay,our method can use more past knowledge to prevent *** conduct extensive evaluations on several popular CL datasets,and experiments show that our method consistently outperforms state-of-the-art methods with various sizes of episodic *** further provide a detailed analysis of these results and demonstrate that our method is more viable in practical scenarios.

关键词： Catastrophic forgetting class-incremental learning continual learning(CL) experience replay

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