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Science China(Information Sciences) 2024年第1期67卷 203-220页

作者： Jie WANG Jiamin LI Pengcheng ZHU Dongming WANG Hongbiao ZHANG Yue HAO Bin SHENG National Mobile Communications Research Laboratory Southeast University 2. Purple Mountain Laboratories China Mobile Research institute

Network-assisted full-duplex(NAFD) cell-free distributed massive multiple-input multipleoutput(MIMO) systems enable uplink(UL) and downlink(DL) communications within the same timefrequency resources,which potentially reduce latency by avoiding the overhead of switching UL/DL ***,how to choose UL/DL modes remains an important factor affecting system *** the dramatic increase in the number of users and access points(APs),massive access brings significant overhead in the mode ***,the different quality of service(QoS) among users also makes the effective utilization of resources *** one of the most promising technologies in sixth-generation(6G),network slicing enables the adaptive configuration of limited UL/DL resources through the resource isolation assisted NAFD ***,we propose a slicing capacity-centered *** this scheme,APs are motivated by slicing requirements and associated slices to form different *** mode selection and resource allocation are performed within each subsystem to reduce overhead and improve resource *** implement this scheme efficiently,a double-layer deep reinforcement learning(DRL)mechanism is used to realize the joint optimization of mode selection and resource *** results show that the slicing capacity-centered scheme can effectively improve resource utilization and reduce overhead.

关键词： network-assisted full-duplex network slicing mode selection resource optimization deep reinforcement learning

Evaluation of Nonbreaking Wave-Induced Mixing Parameterization Schemes Based on a One-Dimensional Ocean Model

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Journal of Ocean University of China 2024年第3期23卷 567-576页

作者： TANG Ran HUANG Chuanjiang DAI Dejun WANG Gang The first institute of {2. Ministry of Natural ResourcesQingdao 266061China Laboratory for Regional oceanography and Numerical Modeling Laoshan LaboratoryQingdao 266237China Shandong Key Laboratory of Marine Science and Numerical Modeling Qingdao 266061China

Surface waves have a considerable effect on vertical mixing in the upper *** the past two decades,the vertical mixing induced through nonbreaking surface waves has been used in ocean and climate models to improve the simulation of the upper *** far,several nonbreaking wave-induced mixing parameterization schemes have been proposed;however,no quantitative comparison has been performed among *** this paper,a one-dimensional ocean model was used to compare the performances of five schemes,including those of Qiao et al.(Q),Hu and Wang(HW),Huang and Qiao(HQ),Pleskachevsky et al.(P),and Ghantous and Babanin(GB).Similar to previous studies,all of these schemes can decrease the simulated sea surface temperature(SST),increase the subsurface temperature,and deepen the mixed layer,thereby alleviating the common thermal deviation problem of the ocean model for upper ocean *** these schemes,the HQ scheme exhibited the weakest wave-induced mixing effect,and the HW scheme exhibited the strongest effect;the other three schemes exhibited roughly the same *** particular,the Q and P schemes exhibited nearly the same *** the simulation based on observations from the Ocean Weather Station Papa,the HQ scheme exhibited the best performance,followed by the Q *** the experiment with the HQ scheme,the root-mean-square deviation of the simulated SST from the observations was 0.43℃,and the mixed layer depth(MLD)was 2.0 *** a contrast,the deviations of the SST and MLD reached 1.2.℃ and 8.4 m,respectively,in the experiment without wave-induced mixing.

关键词： wave-induced mixing surface waves sea surface temperature mixed layer depth General Ocean Turbulence Model

ST-LSTM-SA:A New Ocean Sound Velocity Field Prediction Model Based on Deep Learning

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Advances in Atmospheric Sciences 2024年第7期41卷 1364-1378页

作者： Hanxiao YUAN Yang LIU Qiuhua TANG Jie LI Guanxu CHEN Wuxu CAI first institute of {2. Ministry of Natural ResourcesQingdao 266061China Key Laboratory of Oceanic Surveying and Mapping Ministry of Natural ResourcesQingdao 266061China

The scarcity of in-situ ocean observations poses a challenge for real-time information acquisition in the *** the crucial hydroacoustic environmental parameters,ocean sound velocity exhibits significant spatial and temporal variability and it is highly relevant to oceanic *** this study,we propose a new data-driven approach,leveraging deep learning techniques,for the prediction of sound velocity fields(SVFs).Our novel spatiotemporal prediction model,STLSTM-SA,combines Spatiotemporal Long Short-Term Memory(ST-LSTM) with a self-attention mechanism to enable accurate and real-time prediction of *** circumvent the limited amount of observational data,we employ transfer learning by first training the model using reanalysis datasets,followed by fine-tuning it using in-situ analysis data to obtain the final prediction *** utilizing the historical 12.month SVFs as input,our model predicts the SVFs for the subsequent three *** compare the performance of five models:Artificial Neural Networks(ANN),Long ShortTerm Memory(LSTM),Convolutional LSTM(ConvLSTM),ST-LSTM,and our proposed ST-LSTM-SA model in a test experiment spanning 2.19 to *** results demonstrate that the ST-LSTM-SA model significantly improves the prediction accuracy and stability of sound velocity in both temporal and spatial *** ST-LSTM-SA model not only accurately predicts the ocean sound velocity field(SVF),but also provides valuable insights for spatiotemporal prediction of other oceanic environmental variables.

关键词： sound velocity field spatiotemporal prediction deep learning self-allention

Hyperspectral remote sensing identification of marine oil spills and emulsions using feature bands and double-branch dual-attention mechanism network

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Journal of Oceanology and Limnology 2024年第3期42卷 728-743页

作者： Ning ZHANG Junfang YANG Shanwei LIU Yi MA Jie ZHANG College of oceanography and Space Informatics China University of PetroleumQingdao 266580China first institute of {2. Ministry of Natural ResourcesQingdao 266061China Technology Innovation Center for Ocean Telemetry Ministry of Natural ResourcesQingdao 266061China

The accurate identification of marine oil spills and their emulsions is of great significance for emergency response to oil spill *** selection of characteristic bands with strong separability helps to realize the rapid calculation of data on aircraft or in orbit,which will improve the timeliness of oil spill emergency *** the same time,the combination of spectral and spatial features can improve the accuracy of oil spill *** ground-based experiments were designed to collect measured airborne hyperspectral data of crude oil and its emulsions,for which the multiscale superpixel level group clustering framework(MSGCF)was used to select spectral feature bands with strong *** addition,the double-branch dual-attention(DBDA)model was applied to identify crude oil and its *** with the recognition results based on original hyperspectral images,using the feature bands determined by MSGCF improved the recognition accuracy,and greatly shortened the running ***,the characteristic bands for quantifying the volume concentration of water-in-oil emulsions were determined,and a quantitative inversion model was constructed and applied to the AVIRIS image of the deepwater horizon oil spill event in *** study verified the effectiveness of feature bands in identifying oil spill pollution types and quantifying concentration,laying foundation for rapid identification and quantification of marine oil spills and their emulsions on aircraft or in orbit.

关键词： hyperspectral image spectral analysis dimensionality reduction multiscale superpixel level group clustering framework(MSGCF) double-branch dual-attention(DBDA)

Seasonal variation of mesoscale eddy intensity in the global ocean

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Acta Oceanologica Sinica 2024年第1期43卷 48-58页

作者： Yongcan Zu Yue Fang Shuangwen Sun Libao Gao Yang Yang Guijun Guo first institute of {2./Key Laboratory of Marine Science and Numerical Modeling Ministry of Natural ResourcesQingdao 266061China Laboratory for Regional oceanography and Numerical Modeling Laoshan LaboratoryQingdao 266237China Shandong Key Laboratory of Marine Science and Numerical Modeling Qingdao 266061China

Mesoscale eddies are a prominent oceanic phenomenon that plays an important role in oceanic mass transport and energy *** by rotational speed,the eddy intensity is one of the most fundamental properties of an ***,the seasonal spatiotemporal variation in eddy intensity has not been examined from a global ocean *** this study,we unveil the seasonal spatiotemporal characteristics of eddy intensity in the global ocean by using the latest satellite-altimetry-derived eddy trajectory data *** results suggest that the eddy intensity has a distinct seasonal variation,reaching a peak in spring while attaining a minimum in autumn in the Northern Hemisphere and the opposite in the Southern *** seasonal variation of eddy intensity is more intense in the tropical-subtropical transition zones within latitudinal bands between 15°and 30°in the western Pacific Ocean,the northwestern Atlantic Ocean,and the eastern Indian Ocean because baroclinic instability in these areas changes *** analysis found that the seasonal variation of baroclinic instability precedes the eddy intensity by a phase of 2.3 months due to the initial perturbations needing time to grow into mesoscale eddies.

关键词： seasonal variation mesoscale eddy intensity baroclinic instability global ocean

Study of the ability of SWOT to detect sea surface height changes caused by internal solitary waves

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Acta Oceanologica Sinica 2024年第5期43卷 54-64页

作者： Hao Zhang Chenqing Fan Lina Sun Junmin Meng first institute of {2. Ministry of Natural ResourcesQingdao 266061China Technology Innovation Center for Ocean Telemetry Ministry of Natural ResourcesQingdao 266061China College of oceanography and Space Informatics China University of Petroleum(Huadong)Qingdao 266580China

Surface Water and Ocean Topography(SWOT)is a next-generation radar altimeter that offers high resolution,wide swath,imaging *** has provided free public data worldwide since December *** paper aims to preliminarily analyze the detection capabilities of the Ka-band radar interferometer(KaRIn)and Nadir altimeter(NALT),which are carried out by SWOT for internal solitary waves(ISWs),and to gather other remote sensing images to validate SWOT *** effectively detects ISW surface features and generates surface height variation maps reflecting the modulations induced by ***,its swath width does not completely cover the entire wave packet,and the resolution of L2.L3 level products(about 2.km)cannot be used to identify ISWs with smaller ***,significant wave height(SWH)images exhibit blocky structures that are not suitable for ISW studies;sea surface height anomaly(SSHA)images display systematic leftright *** optimize this imbalance using detrending methods;however,more precise treatment should commence with L1-level *** analysis based on L3-level SSHA data indicates that the average SSHA variation induced by ISWs ranges from 10 cm to 2. *** disturbed by ISWs record unusually elevated SWH and SSHA values,rendering the data unsuitable for analysis and necessitating targeted corrections in future retracking *** the normalized radar cross section,Ku-band and four-parameter maximum likelihood estimation retracking demonstrated greater sensitivity to minor changes in the sea surface,making them more suitable for ISW *** conclusion,SWOT demonstrates outstanding capabilities in ISW detection,significantly advancing research on the modulation of the sea surface by ISWs and remote sensing imaging mechanisms.

关键词： internal solitary waves Surface Water and Ocean Topography(SWOT) Ka-band radar interferometer(KaRIn) Nadir altimeter(NALT) sea surface height anomaly(SSHA) normalized radar cross section(NRCS)

Comprehensive Risk Assessment of Sea Level Rise and Tropical Cyclones in Dongzhaigang Mangroves,China

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Chinese Geographical Science 2024年第4期34卷 631-646页

作者： DING Ruyi CAI Rongshuo YAN Xiuhua LI Cuihua WANG Cui NIE Xinyu Third institute of oceanography Ministry of Natural ResourcesXiamen 361005China

Mangroves play a pivotal role in tropical and subtropical coastal ecosystem,yet they are highly vulnerable to the effects of climate change,particularly the accelerated global sea level rise(SLR)and stronger tropical cyclones(TCs).However,there is a lack of research addressing future simultaneous combined impacts of the slow-onset of SLR and rapid-onset of TCs on China's *** order to develop a comprehensive risk assessment method considering the superimposed effects of these two factors and analyze risk for mangroves in Dongzhaigang,Hainan Island,China,we used observational and climate model data to assess the risks to mangroves under low,intermediate,and very high greenhouse gas(GHG)emission scenarios(such as SSP1-2.6,SSP2.4.5,and SSP5-8.5)in 2.30,2.50,and 2.00,and compiled a risk assessment scheme for mangroves in Dongzhaigang,*** results showed that the combined risks from SLR and TCs will continue to rise;however,SLRs will increase in intensity,and TCs will *** comprehensive risk of the Dongzhaigang mangroves posed by climate change will remain low under SSP1-2.6 and SSP2.4.5 scenarios by 2.30,but it will increase substantially by *** under SSP5-8.5 scenario,the risks to mangroves in Dongzhaigang are projected to increase considerably by 2.50,and approximately 68.8%of mangroves will be at very high risk by *** risk to the Dongzhaigang mangroves is not only influenced by the hazards but also closely linked to their exposure and *** therefore propose climate resilience developmental responses for mangroves to address the effects of climate *** study for the combined impact of TCs and SLR on mangroves in Dongzhaigang,China can enrich the method system of mangrove risk assessment and provide references for scientific management.

关键词： mangrove climate change risk assessment combined hazards sea level rise(SLR) tropical cyclones(TCs) resilience development Dongzhaigang China

Modeling environmental sensitivity and risk assessment of PAHs in sediments along two marine coastal areas in Egypt

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Petroleum Research 2024年第1期9卷 125-142页

作者： Muhammad A.El-Alfy National institute of oceanography and Fisheries NIOFCairoEgypt

Modeling the environmental sensitivity index(ESI)is vital in the planning and management processes,especially along the coastal *** main objectives of the study were to define the main sources of polycyclic aromatic hydrocarbons(PAHs),establish an ESI model,and measure the risk of PAHs on humans and the environment using various *** methodology of the research involved analyzing PAHs according to the EPA 550 methodology in sediments of the coastline in two important coastline areas in Egypt,namely the Gulf of Suez and the Mediterranean Sea,modeling the sensitivity of PAHs using ArcGIS 10.5 by integrating different physical,biological,and land use/cover factors,identifying the sources,and performing a risk *** sediment samples were collected from each *** produced sensitivity map could explain the highly sensitive areas along the Mediterranean Sea and Gulf of Suez coastlines(especially areas that were near drains'outlets,industrial sites,and sea ports).The highest mean PAH concentrations were Acenaphthylene and Fluorine in the Mediterranean Sea and Suez Gulf,***'s obvious that the individual PAH concentrations were within the ERL,ERM,and PEL threshold limits,indicating no adverse biological *** ratios of BaA/BaA+Chy,Flu/Flu+Py,and Ant/Ant+Phe gave an indication that most PAH sources were petrogenic(63.64%)and others(36.36%)were from petroleum *** principle component analysis(PCA)indicated a diverse correlation among the isomer ratios and LU/LC *** carcinogenic risk values were in the very low category(<10^(-6))for both children and *** most significant contributors to carcinogenicity were IP and BkFlu in the Mediterranean Sea and Suez Gulf,*** sources of carbon in seawater,especially with climatic change,may impact the aquatic environment and have impacts on organisms and coral *** it is highly recommended to keep shorelines and seawater free of oil spillage act

关键词： Polycyclic aromatic hydrocarbons(PAHs) Modeling Sensitivity Gulf of Suez And Mediterranean sea

Distribution and influencing factors of microeukaryote in different water layers of the southwestern Indian Ocean Ridge

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Journal of Oceanology and Limnology 2024年第5期42卷 1525-1539页

作者： Zhong LI Chao YUAN Ping SUN Mingzhu FU Xuelei ZHANG Zongling WANG Qinzeng XU College of Environmental Science and Engineering Ocean University of ChinaQingdao 266100China Key Laboratory of Marine Eco-Environmental Science and Technology First Institute of OceanographyMinistry of Natural ResourcesQingdao 266061China

Microeukaryotes play a vital role in shaping marine ecosystems,especially in marine productivity,the microbial food web,and carbon *** Indian Ocean is one of the largest oligotrophic areas in the world,but little is known about the biodiversity of microeukaryotes in the *** community composition and geographical distribution of microeukaryotes collected from the surface(SUR)and deep chlorophyll maximum(DCM)layers in the southwestern Indian Ocean were studied using high-throughput sequencing of the 18S rRNA *** metagenomic data helped quantify the impact of environmental factors on microeukaryotic *** relative abundance of different taxa groups exhibited distinct patterns between SUR and DCM layers,except for the most dominant Dinoflagellata that accounted for more than 40.6%abundance in each *** was much more abundant in the nutrient-rich DCM layer than the SUR *** community similarity of microeukaryotes decreased with increasing of geographic distance,whereas the temperature and inorganic nitrogen were the most important environmental parameters to community *** communities were more influenced by dispersal limitations and rare communities were more responsive to environmental *** network analyses revealed strong biotic interactions indicative of parasitism,predation and competition,and their contribution to microeukaryotic population in diverse ***,this study provided insights into the biodiversity of microeukaryotes by characterizing the differences between water layers and identifying the driving factors in the ocean.

关键词： microeukaryote southwestern Indian Ocean community structure environmental factor biotic interaction Dinoflagellata

Characteristics and triggering mechanisms of early negative Indian Ocean Dipole

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Acta Oceanologica Sinica 2024年第3期43卷 59-65页

作者： Yue Fang Shuangwen Sun Yongcan Zu Jianhu Wang Lin Feng first institute of {2. and Key Laboratory of Marine Science and Numerical ModelingMinistry of Natural ResourcesQingdao 266061China Laboratory for Regional oceanography and Numerical Modeling Qingdao Marine Science and Technology CenterQingdao 266237China Shandong Key Laboratory of Marine Science and Numerical Modeling Qingdao 266061China

Negative Indian Ocean Dipole(nIOD)can exert great impacts on global climate and can also strongly influence the climate in *** nIOD is a major type of nIOD,which can induce more pronounced climate anomalies in summer than La Niña-related ***,the characteristics and triggering mechanisms of early nIOD are *** results based on reanalysis datasets indicate that the early nIOD and La Niña-related nIOD are the two major types of nIOD,and the former accounts for over one third of all the nIOD events in the past six *** two types of nIODs are similar in their intensities,but are different in their spatial patterns and seasonal *** early nIOD,which develops in spring and peaks in summer,is one season earlier than the La Niña-related *** spatial pattern of the wind anomaly associated with early nIOD exhibits a winter monsoon-like pattern,with strong westerly anomalies in the equatorial Indian Ocean and eastly anomalies in the northern Indian *** to the triggering mechanism of early positve IOD,the early nIOD is induced by delayed Indian summer monsoon *** results of this study are helpful for improving the prediction skill of IOD and its climate impacts.

关键词： Indian Ocean Dipole(IOD) triggering mechanism Indian summer monsoon seasonal cycle negative IOD