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LS-AMS: An Adaptive Indexing Structure for Realtime Search on Microblogs

IEEE Transactions on Big Data 2015年第4期1卷 125-137页

作者： Zhao, Feng Liu, Jun Zhou, Jingyu Jin, Hai Yang, Laurence T. Services Computing Technology and System Lab Big Data Technology and System Lab Cluster and Grid Computing Lab School of Computer Science and Technolgoy Huazhong University of Science and Technology Wuhan China Department of Computer Science and Engineering Shanghai Jiao Tong University Shanghai China School of Computer Science and Technology Huazhong University of Science and Technology China Department of Computer Science St. Francis Xavier University Canada

Indexing microblogs for realtime search is challenging, because new microblogs are created at tremendous speed, and user query requests keep constantly changing. To guarantee user obtain complete query results, micro-blogging site maintains huge indices which leads to index fragmentation or extra merging overhead during realtime search. This paper proposes an efficient Log-Structured index structure with Adaptive Merging Strategy (LS-AMS) for realtime search on microblogs. LS-AMS structure consists of an inverted index buffer and a sequence of dynamically adjustable index packages with exponentially increasing sizes. These index packages manage their inverted indices using adaptive merging strategy, which can reduce the merging overhead to improve query performance and can adjust the index structure based on environmental factors, such as the arrival rate of query requests and new microblogs. Experimental results show that LS-AMS can greatly improve query performance without increasing the update cost and improve the self-adaptability in dynamic environment. © 2015 IEEE.

关键词： Merging

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Neural Network-Assisted Hybrid Model Based Message Passing for Parametric Holographic MIMO Near Field Channel Estimation

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IEEE Transactions on Wireless Communications 2025年

作者： Yuan, Zhengdao Guo, Yabo Gao, Dawei Guo, Qinghua Wang, Zhongyong Huang, Chongwen Jin, Ming Wong, Kai-Kit Henan Open University Artificial Intelligence Technology Engineering Research Center Zhengzhou450002 China University of Wollongong School of Electrical Computer and Telecommunications Engineering WollongongNSW2522 Australia Zhengzhou University School of Information Engineering Zhengzhou450002 China Xidian University Hangzhou Institute of Technology Hangzhou311200 China University of Wollongong School of Electrical Computer and Telecommunications Engineering NSW2522 Australia Zhejiang University College of Information Science and Electronic Engineering Hangzhou310027 China Zhejiang Provincial Key Laboratory of Multi-Modal Communication Networks and Intelligent Information Processing Hangzhou310027 China Ningbo University Faculty of Electrical Engineering and Computer Science Ningbo315211 China University College London Department of Electronic and Electrical Engineering Torrington Place WC1E 7JE United Kingdom Yonsei University Yonsei Frontier Lab Seoul Korea Republic of

Holographic multiple-input and multiple-output (HMIMO) is a promising technology with the potential to achieve high energy and spectral efficiencies, enhance system capacity and diversity, etc. In this work, we address the challenge of HMIMO near field (NF) channel estimation, which is complicated by the intricate model introduced by the dyadic Green's function. Despite its complexity, the channel model is governed by a limited set of parameters. This makes parametric channel estimation highly attractive, offering substantial performance enhancements and enabling the extraction of valuable sensing parameters, such as user locations, which are particularly beneficial in mobile networks. However, the relationship between these parameters and channel gains is nonlinear and compounded by integration, making the estimation a formidable task. To tackle this problem, we propose a novel neural network (NN) assisted hybrid method. With the assistance of NNs, we first develop a novel hybrid channel model with a significantly simplified expression compared to the original one, thereby enabling parametric channel estimation. Using the readily available training data derived from the original channel model, the NNs in the hybrid channel model can be effectively trained offline. Then, building upon this hybrid channel model, we formulate the parametric channel estimation problem with a probabilistic framework and design a factor graph representation for Bayesian estimation. Leveraging the factor graph representation and unitary approximate message passing (UAMP), we develop an effective message passing-based Bayesian channel estimation algorithm. Extensive simulations demonstrate the superior performance of the proposed method. © 2025 IEEE.

关键词： Green's function

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Software-as-a-service(SaaS): perspectives and challenges

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science China(Information sciences) 2014年第5期57卷 5-19页

作者： TSAI WeiTek BAI XiaoYing HUANG Yu School of Computing Informatics and Decision Systems Engineering Arizona State University Department of Computer Science and Technology Tsinghua National Lab of Information Science and TechnologyTsinghua University

Software-as-a-service(SaaS)has received significant attention recently as one of three principal components of cloud computing,and it often deals with applications that run on top of a platform-as-a-service(PaaS)that in turn runs on top of infrastructure-as-a-service(IaaS).This paper provides an overview of SaaS including its architecture and major technical issues such as customization,multi-tenancy architecture,redundancy and recovery mechanisms,and ***,a SaaS system can have architecture relating to a database-oriented approach,middleware-oriented approach,service-oriented approach,or PaaS-oriented *** SaaS customization strategies can be used from light customization with manual coding to heavy customization where the SaaS system and its underlying PaaS systems are customized ***-tenancy architecture is an important feature of a SaaS and various trade-offs including security isolation,performance,and engineering effort need to be *** is important for a SaaS system to have multi-level redundancy and recovery mechanisms,and the SaaS system needs to coordinate these with the underlying PaaS ***,SaaS scalability mechanisms include a multi-level architecture with load balancers,automated data migration,and software design strategies.

关键词： software-as-a-service SaaS architecture customization multi-tenancy architecture redundancy and recovery scalability

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A MAPLE PACKAGE OF AUTOMATED DERIVATION OF HOMOTOPY ANALYSIS SOLUTION FOR PERIODIC NONLINEAR OSCILLATIONS

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Journal of Systems science & Complexity 2012年第3期25卷 594-616页

作者： Yinping LIU Shijun LIAO Zhibin LI Department of Computer Science and Technology East China Normal University State Key Lab of Ocean Engineering School of Naval ArchitectureOcean and Civil EngineeringDepartment of MathematicsShanghai Jiaotong University Department of Computer Science East China Normal University

Based on the homotopy analysis method, a general analytic technique for strongly nonlinear problems, a Maple package of automated derivation （ADHO） for periodic nonlinear oscillation systems is presented. This Maple package is valid for periodic oscillation systems in rather general, and can automatically deliver the accurate approximations of the frequency co and the mean of motion δof a nonlinear periodic oscillator. Based on the homotopy analysis method which is valid even for highly nonlinear problems, this Maple package can give accurate approximate expressions even for nonlinear oscillation systems with strong nonlinearity. Besides, the package is user-friendly： One just needs to input a governing equation and initial conditions, and then gets satisfied analytic approximations in few seconds. Several different types of examples are given in this paper to illustrate the validity of this Maple package. Such kind of package provides us a helpful and easy-to-use tool in science and engineering to analyze periodic of this Maple package from the is published publicly. nonlinear oscillations. And it is free address http：//*** to download the electronic version ***/*** once the paper

关键词： Automated derivation homotopy analysis method homotopy Pade technique nonlinear oscillation Wu＇s elimination method.

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Lambda lifting: Transforming programs to recursive equations 2nd

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2nd International Conference on Functional programming Languages and computer Architecture, 1985

作者： Johnsson, Thomas Programming Methodology Group Department of Computer Science Chalmers University of Technology GöteborgS-412 96 Sweden

ISBN: (纸本)9783540159759

Lambda lifting is a technique for transforming a functional program with local function definitions, possibly with free variables in the function definitions, into a program consisting only of global function (combinator) definitions which will be used as rewrite rules. Different ways of doing lambda lifting are presented, as well as reasons for rejecting or selecting the method used in our Lazy ML compiler. A functional program implementing the chosen algorithm is given. © 1985, Springer-Verlag.

关键词： computers

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From soil to the intestinal tract: The key role of beneficial elements and probiotics in promoting health and longevity

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Journal of Environmental Management 2025年 384卷 125611页

作者： Zhang, Wen Wu, Shimao Jho, Eun Hea Chen, Junhao Liu, Qiang Hu, Jian Li, Guanlin Zhao, Xin Sun, Mingming Soil Ecology Lab Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization and Jiangsu Key Laboratory for Solid Organic Waste Utilization Nanjing Agricultural University Nanjing210095 China Department of Agricultural and Biological Chemistry Chonnam National University Gwangju61186 Korea Republic of School of Computer Science and Engineering Nanjing University of Science and Technology Nanjing210094 China Jiangsu Geological Bureau Jiangsu Nanjing210007 China Coastal Saline-alkali Land Ecological Rehabilitation and Sustainable Utilizationment Technology Innovation Center MNR Jiangsu Nanjing210007 China School of Environment and Safety Engineering Jiangsu University Zhenjiang212013 China

Although soil quality and gut probiotics have been extensively accepted as critical for human health, the combined effects of soil and fecal bacteria on public health remain underexplored. This study collected soil and human fecal samples from three towns with high, medium, and low proportion of longevous populations in a well-known longevity region in Yangtze River Delta, China. Beneficial elements were detected in all soils, including selenium (0.01–0.05 mg kg−1), germanium (1.07–1.44 mg kg−1), boron (0.42–1.49 mg kg−1), zinc (1.07–1.70 mg kg−1) and manganese (38.78–43.52 mg kg−1). These elements were more abundant in high-proportion region (HP) compared to medium (MP) and low (LP) proportion region (p © 2025 Elsevier Ltd

关键词： Beneficial elements Fecal bacteria Longevity Probiotic genes Soil bacteria

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Uplink Control Information Based Clustered Access and Discontinuous Reception Management for mMTC

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IEEE Communications Letters 2025年

作者： Wang, Shao-Di Wang, Chang-Long Wang, Hui-Ming Zhou, Feng Leung, Victor C. M. Xidian University Key Laboratory of Electronic Information Countermeasure and Simulation Technology of Ministry of Education Xi’an710071 China Xi’an Jiaotong University School of Information and Communication Engineering Ministry of Education Key Lab for Intelligent Networks and Network Security Xi’an710049 China Shenzhen MSU BIT University Artificial Intelligence Research Institute Shenzhen518172 China Shenzhen University College of Computer Science and Software Engineering Shenzhen518060 China The University of British Columbia Department of Electrical and Computer Engineering VancouverBCV6T 1Z4 Canada

Uplink control information (UCI) and discontinuous reception (DRX) play important roles for massive machine type communication (mMTC). Despite their standalone significance, a conspicuous gap exists in comprehensively exploring the synergy between UCI and DRX concerning both energy conservation and latency reduction for mMTC. In this letter, we propose a UCI-based clustered access and DRX management (UCADM) scheme that strikes a balance between these two critical performance metrics, reducing energy usage while preserving low latency in uplink-downlink interaction for mMTC. Specifically, we present a strictly feasible solution for the proposed UCADM scheme by using the spectral radius and the constraint projection, which can effectively solve DRX switching operations as indicated by scheduling information from UCI. Simulation results confirm the effectiveness of our scheme. © 1997-2012 IEEE.

关键词： Information management

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Attitude Control of Rigid Body with Inertia Uncertainty and Saturation Input

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Tsinghua science and technology 2017年第1期22卷 83-91页

作者： Xi Ma Fuchun Sun Hongbo Li Bing He Department of Computer Science and Technology Tsinghua UniversityState Key Lab of Intelligent Technology and Systemsand Tsinghua National Laboratory for Information Scienceand Technology (TNList) Department of Aerospace Engineering High-Tech Institute of Xi’an

In this paper, the attitude control problem of rigid body is addressed with considering inertia uncertainty,bounded time-varying disturbances, angular velocity-free measurement, and unknown non-symmetric saturation input. Using a mathematical transformation, the effects of bounded time-varying disturbances, uncertain inertia,and saturation input are combined as total disturbances. A novel finite-time observer is designed to estimate the unknown angular velocity and the total disturbances. For attitude control, an observer-based sliding-mode control protocol is proposed to force the system state convergence to the desired sliding-mode surface; the finite-time stability is guaranteed via Lyapunov theory analysis. Finally, a numerical simulation is presented to illustrate the effective performance of the proposed sliding-mode control protocol.

关键词： attitude control inertial uncertainty angular velocity-free measurement saturation input finite-time observer sliding-mode control

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Effects on prey-predator with different functional responses

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International Journal of Biomathematics 2017年第8期10卷 141-162页

作者： Banani Roy Sankar Kumar Roy M. H. A. Biswas Department of Applied Mathematicswith Oceanology and Computer Programming Vidyasagar University Midnapore 721102 West Bengal India Mathematics Discipline Science Engineering and Technology SchoolKhulna University Khulna 9208 Bangladesh

In this paper, we investigate the effects on prey of two predators which are also related in terms of prey-predator relationship. Different types of functional responses are con- sidered to formulate the mathematical model for predator and generalist predator of our proposed model. Harvesting effort for the generalist predator is considered and the density-dependent mortality rate for predator and generalist predator is incorporated in our proposed model. Local stability as well as global stability for the system is dis- cussed. We analyze the different bifurcation parameters to evaluate Hopf bifurcation in the neighborhood of interior equilibrium point. Finally, some numerical simulations and graphical figures are provided to verify our analytical results with the help of different sets of parameters.

关键词： Prey-predator model local and global stabilities Hopf bifurcation.

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A critical review on decade progress and future prospects of P3HT:PCBM bulk heterojunction solar cells

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Solar Energy 2025年 297卷

作者： Balraj, Babu Raja, M. Prabhu, T.G. Vignesh Balaji, M. Chandrasekaran, J. Nagarajan, Senthil Kumar Bharathi, Mohanbabu Lee, Sejoon Sivakumar, Chandrasekar Department of Physics Vel Tech Rangarajan Dr Sagunthala R&D Institute of Science and Technology Tamil Nadu Chennai 600062 India Department of Physics Vivekanandha College of Arts and Science for Women Tamil Nadu Namakkal 637205 India Department of Physics Sri Ramakrishna Mission Vidyalaya College of Arts and Science Tamil Nadu Coimbatore 641 020 India Department of Electrical & Computer Engineering National University of Singapore Singapore 117608 Singapore Postgraduate and Research Department of Physics Nanotechnology Lab Kongunadu Arts and Science College Tamilnadu Coimbatore 641029 India Centre for Research Impact & Outcome Chitkara University Rajpura 140401 Punjab India Department of Semiconductor Science Dongguk University-Seoul Seoul 04620 South Korea Department of Physics National Chung Hsing University Taichung City 40227 Taiwan

In recent years, Π-conjugated polymer:fullerene-based bulk heterojunction (BHJ) solar cells have received significant attention since combining a narrow P3HT donor and a high electron affinity PCBM acceptor blend could help achieve high efficiencies. In order to compete with other organic solar cell materials, further optimization of P3HT:PCBM-based BHJ has to be done to improve the device's efficiency. This review traces the historical development of bulk heterojunction, architecture, and its PV characterizations, presents the various work functions of the active layer, different charge transport interface layers and electrodes of P3HT:PCBM-based BHJ solar cells, and P3HT:PCBM-based inverted and tandem device structures. Besides, the PCE performance of different material combinations is listed better to understand the P3HT:PCBM-based BHJ solar cells. This review concludes by discussing the optimization of different PV parameters and fabrication technologies of the BHJ. © 2025 International Solar Energy Society

关键词： Buffer layers Bulk heterojunction solar cells P3HT:PCBM blend Processing parameters PV characteristics

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