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Acta Oceanologica Sinica 2023年第10期42卷 117-126页

作者： yunzhou li Juncheng Wang College of Meteorology and Oceanography National University of Defense TechnologyChangsha 410073China Institute of Oceanographic Instrumentation Qilu University of Technology(Shandong Academy of Sciences)Qingdao 266061China School of Ocean Technology Sciences Qilu University of Technology(Shandong Academy of Sciences)Qingdao 266061China Laoshan Laboratory Qingdao 266237China

In China,operational in-situ marine monitoring is the primary means of directly obtaining hydrological,meteorological,and oceanographic environmental parameters across sea areas,and it is essential for applications such as forecast of marine environment,prevention and mitigation of disaster,exploitation of marine resources,marine environmental protection,and management of transportation *** this paper,we summarise the composition,development courses,and present operational status of three systems of operational in-situ marine monitoring,namely coastal marine automated network station,ocean data buoy and voluntary observing ship measuring and reporting ***,we discuss the technical development in these in-situ systems and achievements in the key generic technologies along with future development trends.

关键词： marine observation technology operational in-situ marine monitoring C-MAN station ocean data buoy VOS measuring and reporting system achievements in the key technologies development trend

Allocation of Network Error Correction Flow on Disjoint Paths

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Tsinghua Science and Technology 2015年第2期20卷 182-187页

作者： Zhiqing Xiao yunzhou li Jing Wang the Department of Electronic Engineering Tsinghua University the Research Institute of Information Technology Tsinghua University

The diversity provided by disjoint paths can increase the survivability of communication networks. This paper considers the allocation of network error correction flow on a network that consists of disjoint paths from the source node to the destination node. Specifically, we propose an algorithm of allocating the path-flows to support the given rate with minimum cost. Our analysis shows that the asymptotic time complexity of this algorithm is linearithmic, and this algorithm is optimal in general

关键词： network survivability disjoint paths maximum distance separable codes network error correction

Queue-aware energy-efficient scheduling and power allocation with feedback reduction in small-cell networks

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Science China(Information Sciences) 2018年第4期61卷 246-252页

作者： Hongxin WEI yunzhou li limin XIAO Shidong ZHOU State Key Laboratory on Microwave and Digital Communications Tsinghua National Laboratory Information Science and Technology Department of Electronic Engineering Tsinghua University

In small cell networks(SCNs),the path loss becomes smaller,and energy efficiency could be *** plenty of small base stations(BSs)are deployed,the energy consumption of each BSs can be small enough to make the total ene... 详细信息

关键词： CSI Queue-aware energy-efficient scheduling and power allocation with feedback reduction in small-cell networks

Developing an intermediate-complexity projection model for China's fisheries:A case study of small yellow croaker(Larimichthys polyactis)in the Haizhou Bay,China

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Acta Oceanologica Sinica 2021年第8期40卷 108-118页

作者： Ming Sun yunzhou li Yiping Ren Yong Chen Fisheries College Ocean University of ChinaQingdao 266003China School of Marine Sciences University of MaineMaine 04469USA Field Observation and Research Station of Haizhou Bay Fishery Ecosystem Ministry of EducationQingdao 266003China Laboratory for Marine Fisheries Science and Food Production Processes Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China

Projection models are commonly used to evaluate the impacts of ***,previously developed projection tools were not suitable for China’s fisheries as they are either overly complex and data-demanding or too simple to reflect the realistic management ***,an intermediate-complexity projection model was developed that could adequately describe fish population dynamics and account for management measures including mesh size limits,summer closure,and spatial closure.A two-patch operating model was outlined for the projection model and applied to the heavily depleted but commercially important small yellow croaker(Larimichthys polyactis)fishery in the Haizhou Bay,China,as a case *** model was calibrated to realistically capture the fisheries dynamics with *** simulation scenarios featuring different fishing intensities based on status quo and maximum sustainable yield(MSY)were proposed and evaluated with *** projections were additionally performed to investigate the influence of uncertainty associated with recruitment strengths and the implementation of control *** was found that fishing at FMSY level could effectively rebuild the depleted stock biomass,while the stock collapsed rapidly in the status quo *** in recruitment and implementation could result in variabilities in management effects;but they did not much alter the management effects of the FMSY *** results indicate that the lack of science-based control targets in fishing mortality or catch limits has hindered the achievement of sustainable fisheries in ***,the presented work highlights that the developed projection model can promote the understanding of the possible consequences of fishing under uncertainty and is applicable to other fisheries in China.

关键词： two-patch operating model simulation maximum sustainable yield control targets uncertainty

Static CSI Extraction and Application in the Tomographic Channel Model

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China Communications 2019年第12期16卷 132-144页

作者： Haihan li yunzhou li Shidong Zhou Jing Wang Beijing National Research Center for Information Science and Technology Tsinghua UniversityBeijing 100084China Department of Electronic Engineering Tsinghua UniversityBeijing 100084China

In this paper, the statistical properties of parameters of each path in wireless channel models are analyzed to prove that there is the static part in channel state information(CSI) which can be extracted from huge amounts of CSI data. Based on the analysis, the concept of the Tomographic Channel Model(TCM) is presented. With cluster algorithms, the static CSI database can be built in an off-line manner. The static CSI database can provide prior information to help pilot design to reduce overhead and improve accuracy in channel estimation. A new CSI prediction method and a new channel estimation method between different frequency bands are introduced based on the static CSI database. Using measurement data, the performance of the new channel prediction method is compared with that of the Auto Regression(AR) predictor. The results indicate that the prediction range of the new method is better than that of the AR method and the new method can predict with fewer pilot symbols. Using measurement data, the new channel estimation method between different frequency bands can estimate the CSI of one frequency band based on known CSI of another frequency band without any feedback.

关键词： big data tomographic channel model channel prediction channel estimation channel feedback K-means clustering

A nonlinear wake model of a wind turbine considering the yaw wake steering

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Journal of Oceanology and limnology 2024年第3期42卷 715-727页

作者： yunzhou li Zhiteng GAO Shoutu li Suiping QI Xiaoyu TANG College of Meteorology and Oceanography National University of Defense TechnologyChangsha 410073China Multi-function Towing Tank School of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China School of Energy and Power Engineering Lanzhou University of TechnologyLanzhou 730050China Institute of Oceanographic Instrumentation Qilu University of Technology(Shandong Academy of Sciences)Qingdao 266061China State Key Laboratory of Industrial Control Technology College of Control Science and EngineeringZhejiang UniversityHangzhou 310027China Laoshan Laboratory Qingdao 266237China

Duo to fluctuations in atmospheric turbulence and yaw control strategies,wind turbines are often in a yaw *** predict the far wake velocity field of wind turbines quickly and accurately,a wake velocity model was derived based on the method of momentum conservation considering the wake steering of the wind turbine under yaw *** consider the shear effect of the vertical incoming wind direction,a two-dimensional Gaussian distribution function was introduced to model the velocity loss at different axial positions in the far wake region based on the assumption of nonlinear wake *** work also developed a“prediction-correction”method to solve the wake velocity field,and the accuracy of the model results was verified in wake experiments on the Garrad Hassan wind ***,a 33-kW two-blade horizontal axis wind turbine was simulated using this method,and the results were compared with the classical wake model under the same parameters and the computational fluid dynamics(CFD)simulation *** results show that the nonlinear wake model well reflected the influence of incoming flow shear and yaw wake steering in the wake velocity ***,computation of the wake flow for the Horns Rev offshore wind farm with 80 wind turbines showed an error within 8%compared to the experimental *** established wake model is less computationally intensive than other methods,has a faster calculation speed,and can be used for engineering calculations of the wake velocity in the far wakefield of wind turbines.

关键词： far wake wake model wake steering wind shear wind farm

Energy-Efficient Resource Allocation for Small-Cell Networks：A Stable Queue Perspective

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China Communications 2017年第10期14卷 142-150页

作者： Hongxin Wei Wei Feng yunzhou li Shidong Zhou State Key Laboratory on Microwave and Digital CommunicationsTsinghua National Laboratory Information Science and Technology Department of Electronic Engineering Tsinghua University Beijing 100084 China

The small-cell technology is promising for spectral-efficiency enhancement. However, it usually requires a huge amount of energy consumption. In this paper, queue state information and channel state information are jointly utilized to minimize the time average of overall energy consumption for a multi-carrier small-cell network, where the inter-cell interference is an intractable problem. Based on the Lyapunov optimization theory, the problem could be solved by dynamically optimizing the problem of user assignment, carrier allocation and power allocation in each time slot. As the optimization problem is NP-hard, we propose a heuristic iteration algorithm to solve it. Numerical results verify that the heuristic algorithm offers an approximate performance as the brute-force algorithm. Moreover, it could bring down the overall energy consumption to different degrees according to the variation of traffic load. Meanwhile, it could achieve the same sum rate as the algorithm which focuses on maximizing system sum rate.

关键词： resource allocation small cell queue system sum rate

Convolutional Neural Networks Based Indoor Wi-Fi Localization with a Novel Kind of CSI Images

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China Communications 2019年第9期16卷 250-260页

作者： Haihan li Xiangsheng Zeng yunzhou li Shidong Zhou Jing Wang Beijing National Research Center for Information Science and Technology Tsinghua UniversityBeijing 100084China Department of Electronic Engineering Tsinghua UniversityBeijing 100084China

Indoor Wi-Fi localization of mobile devices plays a more and more important role along with the rapid growth of location-based services and Wi-Fi mobile *** this paper,a new method of constructing the channel state information(CSI)image is proposed to improve the localization *** with previous methods of constructing the CSI image,the new kind of CSI image proposed is able to contain more channel information such as the angle of arrival(AoA),the time of arrival(TOA)and the *** construct three gray images by using phase differences of different antennas and amplitudes of different subcarriers of one antenna,and then merge them to form one RGB *** localization method has off-line stage and on-line *** the off-line stage,the composed three-channel RGB images at training locations are used to train a convolutional neural network(CNN)which has been proved to be efficient in image *** the on-line stage,images at test locations are fed to the well-trained CNN model and the localization result is the weighted mean value with highest output *** performance of the proposed method is verified with extensive experiments in the representative indoor environment.

关键词： convolutional neural network indoor Wi-Fi localization channel state information CSI image

A Learning-Based Channel Model for Synergetic Transmission Technology

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China Communications 2015年第9期12卷 83-92页

作者： liang Chen li Haihan li yunzhou Zhou Shidong Wang Jing State Key Laboratory on Microwave and Digital Communications Tsinghua National Laboratory for Information Science and Technology Tsinghua University Department of Electronic Engineering Tsinghua University

It is extensively approved that Channel State Information(CSI) plays an important role for synergetic transmission and interference management. However, pilot overhead to obtain CSI with enough precision is a significant issue for wireless communication networks with massive antennas and ultra-dense cell. This paper proposes a learning- based channel model, which can estimate, refine, and manage CSI for a synergetic transmission system. It decomposes the channel impulse response into multiple paths, and uses a learning-based algorithm to estimate paths' parameters without notable degradation caused by sparse pilots. Both indoor measurement and outdoor measurement are conducted to verify the feasibility of the proposed channel model preliminarily.

关键词： channel model CSI synergetic transmission spectral efficiency learning-based channel measurement

Current situation and trend of marine data buoy and monitoring network technology of China

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Acta Oceanologica Sinica 2016年第2期35卷 1-10页

作者： WANG Juncheng WANG Zhongqiu WANG Yiming liU Shixuan li yunzhou Shandong Provincial Key Laboratory of Ocean Environment Monitoring Technology Qingdao 266001 China Institute of Oceanographic Instrumentation Shandong Academy of Science Qingdao 266001 China The First Institute of Oceanography State Oceanic Administrtion Qingdao 266061 China

Marine data buoy can provide a long-term, continuous, real-time, reliable data of ocean observation in a variety of complex marine environment. It is one of the most reliable, most effective and important means of ocean monitoring technology. In this paper, the classification, main theory and technology system of marine data buoy are summarized. The typical technological breakthrough of the development of marine data buoy in recent years is summarized. The composition and application of marine monitoring network in China was introduced, and the gap between the technology of China＇s marine data buoy and the international advanced countries is *** on the situation and demand of China＇s current situation and needs, the development trend of marine data buoy and buoy monitoring network are expected.

关键词： marine monitoring buoy marine observation monitoring network current situation and trend