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Seasonal variability in free-living marine nematode community structure in a sandy beach of the Taiping Bay of Qingdao,China

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Acta Oceanologica Sinica 2008年第2期27卷 102-115页

作者： LIU Haibin ZHANG Zhinan FAN Shiliang HUA Er deng ke College of Marine Life Science Ocean University of China Qingdao 266003 China Liaoeheng Agriculture Bureau Liaocheng 252000 China

Nematode assemblage composition, trophic structure and biodiversity were followed over an annual cycle in a sandy beach of the Taiping Bay of Qingdao, China. Nematode assemblage in the sandy beach maintained a high genus diversity （75 genera）. Mlero- laimus and Bathylaimus were the dominant genus of the nematode assemblage, accounting for 66% of the total nematode abundance. The nematodes＇ dominant trophic structure changed seasonally as a response to the seasonal changes in food quality. Epigrowth-feeder nematodes （2A） were the dominant trophic groups in the trophic structure with the highest abundance in spring because of phytoplankton bloom, while the feeding type （ 1 B） showed higher abundance in summer that was due to the increasing of sediment detritus after spring bloom. Furthermore, species diversity and evenness calculated on nematodes identified to the genus level displayed significant temporal changes, which was also reflected by the index of trophic diversity. According to the cluster analysis, the nematode community structure of the whole year was clearly separated into two periods （A and B）. Biota-Envlron- ment matching （BIOENV） results showed that seawater temperature, sediment Chl a and grain size were responsible for the nema- tode community structure variation in spring and summer period （Period A）. However, seawater/interstitial water temperature, interstitial water dissolved oxygen concentration,interstitial water salinity, and sediment Ph a a were more important in constructing the autumn and winter period （Period B） nematode community structure.

关键词： nematode assemblage composition trophic structure temporal change Taiping Bay of Qingdao

A simple amplify-and-forward opportunistic relaying based on outdated channel state information

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Science China(Information Sciences) 2014年第6期57卷 5-18页

作者： WANG Chao deng ke LI YuBo YIN QinYe ZHUANG LiLi School of Electronic and Information Engineering Xian Jiaotong University China Taiyuan Satellite Launch Center

Opportunistic relay selection(ORS)is a promising approach for cooperative communications owing to its low complexity by activating only the best ***,in mobile scenarios,the channel state information(CSI)estimated in relay selection may be different from the actual CSI employed in data transmission due to relatively fast varying channels,i.e.,CSI is outdated,which may lead to incorrect relay selection,and hence system performance *** address the problem,this paper designs a relay selection strategy with instaneous and statistical CSIs in amplify-and-forward(AF)cooperative networks whose instantaneous CSIs of two hops employed in relay selection are both *** on high signal-to-noise ratio(SNR)analysis,we propose a distinctive relay selection strategy which can be described as selecting the relay with the asymptotic optimum average symbol error probability(SEP)and outage probability at high *** corresponding asymptotic outage probability and SEP performance analysis are also ***,simulation results not only validate our theoretical analysis,but also show that in asymmetrical outdated CSI scenarios,the proposed strategy achieves better performance than existing relay selection strategies at medium and high SNR values.

关键词： relay selection outdated CSI amplify-and-forward outage probability symbol error probability

Spatial flow influence factor: A novel concept for indoor air pollutant control

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Science China(Technological Sciences) 2006年第1期49卷 115-128页

作者： ZHANG Yinping LI Xiaofeng WANG Xinke deng Wei QIAN ke Department of Building Science Tsinghua University Beijing 100084 China Department of Building Science Tsinghua University Beijing 100084 China Department of Building Science Tsinghua University Beijing 100084 China Department of Building Science Tsinghua University Beijing 100084 China Department of Building Science Tsinghua University Beijing 100084 China

This paper puts forward a novel concept, the spatial flow influence factor (SFIF), which provides a new insight into the airflow structure. This concept is very helpful in the control of indoor air pollutants since: (1) for a given indoor airflow; given sources of volatile organic compounds (VOCs), the optimal arrangement of the VOC sources can easily be obtained; (2) for given positions of VOC sources; occupied regions (or target regions), the optimal indoor airflow pattern or organization can be determined; (3) the SFIF for an indoor space can also be regarded as the indoor air safety index of that space. To illustrate this concept, we present several examples of applying a SFIF to indoor air VOC control.

关键词： volatile organic compounds, indoor air quality, indoor air pollutant control, spatial flow influence factor.

Improved expert selection model for forex trading

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Frontiers of Computer Science 2018年第3期12卷 518-527页

作者： Jia ZHU Xingcheng WU Jing XIAO Changqin HUANG Yong TANG ke deng School of Computer Science South China Normal University Guangzhou 510631 China School of Computer Science and Information Technology Royal Melbourne Institute of Technology Melbourne 3000 Australia

Online prediction is a process that repeatedly predicts the next element in the coming period from a sequence of given previous elements. This process has a broad range of applications in various areas, such as medical, streaming media, and finance. The greatest challenge for online prediction is that the sequence data may not have explicit features because the data is frequently updated, which means good predictions are difficult to maintain. One of the popular solutions is to make the prediction with expert advice, and the challenge is to pick the right experts with minimum cumulative loss. In this research, we use the forex trading prediction, which is a good example for online prediction, as a case study. We also propose an improved expert selection model to select a good set of forex experts by learning previously observed sequences. Our model considers not only the average mistakes made by experts, but also the average profit earned by experts, to achieve a better performance, particularly in terms of financial profit. We demonstrate the merits of our model on two real major currency pairs corpora with extensive experiments.

关键词： online learning expert selection forex prediction

Insight into the structural transformation of tetraphenylethylene acids at liquid–solid interface induced by linear aminofunctionalized triazine derivatives and annealing treatment

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Nano Research 2023年第12期16卷 13335-13342页

作者： Ting Meng Xuan Peng Xunwen Xiao ke deng Yu-Wu Zhong Qingdao Zeng CAS key Laboratory of Standardization and Measurement for Nanotechnology CAS Center for Excellence in NanoscienceNational Center for Nanoscience and Technology(NCNST)Beijing 100190China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China School of Science Nanchang Institute of TechnologyNanchang 330099China Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of PhotochemistryInstitute of ChemistryChinese Academy of SciencesBeijing 100190China College of Materials and Chemical Engineering Ningbo University of TechnologyNingbo 315211China

The interaction between organic photoelectric molecules leads to the formation of a certain aggregation structure,which plays a pivotal role in the charge transport at the intermolecular *** view of this,we investigated the mechanism and law of intermolecular interaction by detecting the self-assembled behaviors between organic photoelectric molecules at the interface by scanning tunneling microscopy(STM).In this work,the structural transformations of tetraphenylethylene acids(H_(4)ETTCs)on graphite surface induced by temperature and triazine derivatives(zcy-19,zcy-27,and zcy-38 molecules)were studied by STM technology and density functional theory(DFT)*** room temperature,zcy-19 and H_(4)ETTC molecules formed a small range of ordered co-assembled nanostructure,while for zcy-27 or zcy-38 molecules,no co-assembled nanostructures were observed and only their own self-assembled structures existed on graphite surface,*** the thermal annealing trials,the original co-assembled H_(4)ETTC/zcy-19 structure disappeared,and only zcy-19 and H_(4)ETTC self-assembled in separate ***,new well-ordered H_(4)ETTC/zcy-27 or H_(4)ETTC/zcy-38 co-assembled structures appeared at different annealing temperatures,*** with DFT calculations,we further analyzed the mechanism of such structural transformations by triazine derivatives and *** reveal that triazine derivatives could interact with H_(4)ETTC by N–H···O and O–H···N hydrogen bondings,and whether temperature or zcy series compounds could achieve successful regulation of H_(4)ETTC assembly behavior is closely associated with the conjugated skeleton length of zcy series compounds.

关键词： tetraphenylethylene acids triazine derivatives annealing treatment scanning tunneling microscopy(STM)

THE FLOW ANALYSIS OF FLUIDS IN FRACTAL RESERVOIR WITH THE FRACTIONAL DERIVATIVE

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Journal of Hydrodynamics 2006年第3期18卷 287-293页

作者： TIAN Ji TONG deng-ke Institute of Mechanics Chinese Academy of ScienceBeijing 100080China Gudong Petroleum Factory of Shengli Petroleum Administration Dongying 256504China Departmentof Applied Mathematics China University of Petroleum Dongying 257061 China

In this paper, fractional order derivative, fractal dimension and spectral dimension are introduced into the seepage flow mechanics to establish the flow models of fluids in fractal reservoirs with the fractional derivative. The flow characteristics of fluids through a fractal reservoir with the fractional order derivative are studied by using the finite integral transform, the discrete Laplace transform of sequential fractional derivatives and the generalized Mittag-Leffler function. Exact solutions are obtained for arbitrary fractional order derivative. The long-time and short-time asymptotic solutions for an infinite formation are also obtained. The pressure transient behavior of fluids flow through an infinite fractal reservoir is studied by using the Stehfest＇s inversion method of the numerical Laplace transform. It shows that the order of the fractional derivative affect the whole pressure behavior, particularly, the effect of pressure behavior of the early-time stage is larger The new type flow model of fluid in fractal reservoir with fractional derivative is provided a new mathematical model for studying the seepage mechanics of fluid in fractal porous media.

关键词： fractional calculus porous media fractal,integral transform exact solution

Quantum Solitons and Localized Modes in a One-Dimensional Lattice Chain with Nonlinear Substrate Potential

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Communications in Theoretical Physics 2006年第5期45卷 869-872页

作者： LI De-Jun MI Xian-Wu deng ke TANG Yi Department of Physics Jishou University Jishou 416000 China Department of Physics Xiangtan University Xiangtan 411105 China

In the classical lattice theory, solitons and localized modes can exist in many one-dimensional nonlinear lattice chains, however, in the quantum lattice theory, whether quantum solitons and localized modes can exist or not in the one-dimensional lattice chains is an interesting problem. By using the number state method and the Hartree approximation combined with the method of multiple scales, we investigate quantum solirons and localized modes in a one-dimensional lattice chain with the nonlinear substrate potential. It is shown that quantum solitons do exist in this nonlinear lattice chain, and at the boundary of the phonon Brillouin zone, quantum solitons become quantum localized modes, phonons are pinned to the lattice of the vicinity at the central position j = j0.

关键词： number state method Hartree approximation quantum envelope soliton quantum localized mode

Coronene and Bipyridine Derivatives Inducing Diversified Structural Transitions of Carboxylic Acids at the Liquid/Solid Interface

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Chinese Journal of Chemistry 2022年第23期40卷 2727-2733页

作者： Ting Meng Peng Lei Yufei Zhang ke deng Xunwen Xiao Qingdao Zeng CAS key Laboratory of Standardization and Measurement for Nanotechnology CAS Centerfor Excellence in NanoscienceNational Center forNanoscienceandTechnology(NCNST)Beijing 100190China Center of Materials Scienceand Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China School of Materials and Chemical Engineering Ningbo University of TechnologyNingboZhejiang 315211China

In recent years, the construction of stable multicomponent assembled structures on surfaces and the exploration of the assembled mechanism have become research hotspots. In this paper, the azobenzene-carboxylic acid called (E)-4’,4”’-(diazene-1,2-diyl) bis(([1,1’-biphenyl]-3,5-dicarboxylic acid)) (H4DBBD) could self-assemble into regular network structure at heptanoic acid/graphite via hydrogen bonding, and could be regulated into analogous kagomé network by coronene (COR) molecules. In addition, a series of bipyridine derivatives were further introduced to construct bi-component systems with H4DBBD molecules, and successfully induced diversified structural transitions of H4DBBD on the graphite surface. Combined with scanning tunneling microscope (STM) and density functional theory (DFT) calculations, we have investigated the diversified structural transitions and analyzed the formation mechanism of the assembled systems.

关键词： Self-assembly Supramolecular chemistry Scanning tunneling microscope DFT calculations Hydrogen bonds

Multi-User Detection for Spatial Modulation toward 5G Wireless Communications

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China Communications 2017年第12期14卷 100-110页

作者： Shiwen Fan, Yue Xiao Xia Lei Rong Shi ke deng Shaoqian Li National key Laboratory of Science and Technology on Communications University of Electronic Science and Technology of China Chengdu 611731 China The National Mobile Communications Research Laboratory Southeast University Nanjing 210096 China Science and Technology on Electronic Information Control Laboratory the 29th Research Institute of China Electronics

Spatial modulation(SM) is a class of novel multiple-input multiple-output(MIMO) techniques toward future wireless communications,which activates only one transmit antenna in each time slot,so as to reduce the number of RF chains for saving the implement ***,considering its application in 5G systems with multiple users,the detection of multi-user spatial modulation has drawn greater *** this paper,a pair of efficient detectors are proposed for multi-user spatial ***,a threshold-aided approximate message passing(T-AMP) detector is proposed with the purpose of reducing the computational complexity of traditional structured approximate message passing(Str-AMP) *** addition,a novel probability sorting aided approximate message passing detector,called probability-ranking-aided AMP detector(P-AMP),is also proposed with the purpose of improving the *** results show that the proposed T-AMP detector is able to achieve similar performance as traditional StrAMP with lower complexity,while the proposed P-AMP detector exhibits a better symbol error rate(SER) performance with similar complexity.

关键词： multi-user spatial modulation probability sorting message passing.