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Properties of focused Laguerre–Gaussian beam propagating in anisotropic ocean turbulence

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Chinese Physics B 2024年第2期33卷 386-393页

作者：王新光马洋斌袁邱杰陈伟王乐赵生妹 College of Science Nanjing University of Posts and TelecommunicationsNanjing 210003China institute of Signal Processing and Transmission Nanjing University of Posts and TelecommunicationsNanjing 210003China Key Lab of Broadband Wireless Communication and Sensor network Technology(Ministry of Education) Nanjing University of Posts and TelecommunicationsNanjing 210003China National Laboratory of Solid State Microstructures Nanjing UniversityNanjing 210093China

We analyze the properties of a focused Laguerre–Gaussian(LG)beam propagating through anisotropic ocean turbulence based on the Huygens–Fresnel *** the Rytov approximation theory,we derive the analytical formula of the channel capacity of the focused LG beam in the anisotropic ocean turbulence,and analyze the relationship between the capacity and the light source parameters as well as the turbulent ocean *** is found that the focusing mirror can greatly enhance the channel capacity of the system at the geometric focal plane in oceanic *** results also demonstrate that the communication link can obtain high channel capacity by adopting longer beam wavelength,greater initial beam waist radius,and larger number of transmission ***,the capacity of the system increases with the decrease of the mean squared temperature dissipation rate,temperature-salinity contribution ratio and turbulence outer scale factor,and with the increase of the kinetic energy dissipation rate per unit mass of fluid,turbulence inner scale factor and anisotropy *** to a Hankel–Bessel beam with diffraction-free characteristics and unfocused LG beam,the focused LG beam shows superior anti-turbulence interference properties,which provide a theoretical reference for research and development of underwater optical communication links using focused LG beams.

关键词： vortex beam orbital angular momentum focusing mirror anisotropic turbulence

Learning group interaction for sports video understanding from a perspective of athlete

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Frontiers of Computer Science 2024年第4期18卷 175-188页

作者： Rui HE Zehua FU Qingjie LIU Yunhong WANG Xunxun CHEN Intelligent Recognition and Image Processing(IRIP)Lab School of Computer Science and EngineeringBeihang UniversityBeijing 100191China Hangzhou Innovation institute Behang UniversityHangzhou 310051China National Computer network Emergency Response Technical Team/Coordination Center of China(CNCERT or CNCERT/CC) Beijing 100029China

Learning activities interactions between small groups is a key step in understanding team sports *** research focusing on team sports videos can be strictly regarded from the perspective of the audience rather than the *** team sports videos such as volleyball and basketball videos,there are plenty of intra-team and inter-team *** this paper,a new task named Group Scene Graph Generation is introduced to better understand intra-team relations and inter-team relations in sports *** tackle this problem,a novel Hierarchical Relation network is *** all players in a video are finely divided into two teams,the feature of the two teams’activities and interactions will be enhanced by Graph Convolutional networks,which are finally recognized to generate Group Scene *** evaluation,built on Volleyball dataset with additional 9660 team activity labels,a Volleyball+dataset is proposed.A baseline is set for better comparison and our experimental results demonstrate the effectiveness of our ***,the idea of our method can be directly utilized in another video-based task,Group Activity *** show the priority of our method and display the link between the two ***,from the athlete’s view,we elaborately present an interpretation that shows how to utilize Group Scene Graph to analyze teams’activities and provide professional gaming suggestions.

关键词： group scene graph group activity recognition scene graph generation graph convolutional network sports video understanding

Improved decoy-state quantum key distribution with uncharacterized heralded single-photon sources

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Chinese Physics B 2024年第2期33卷 204-208页

作者：徐乐辰张春辉周星宇王琴 institute of Quantum Information and Technology Nanjing 210003China Broadband Wireless Communication and Sensor network Technology Key Laboratory of Ministry of EducationNanjing University of Posts and TelecommunicationsNanjing 210003China Telecommunication and networks National Engineering Research Center Nanjing University of Posts and TelecommunicationsNanjing 210003China

Encoding system plays a significant role in quantum key distribution(QKD).However,the security and performance of QKD systems can be compromised by encoding misalignment due to the inevitable defects in realistic *** alleviate the influence of misalignments,a method exploiting statistics from mismatched basis is proposed to enable uncharacterized sources to generate secure keys in *** this work,we propose a scheme on four-intensity decoy-state quantum key distribution with uncharacterized heralded single-photon *** only requires the source states are prepared in a two-dimensional Hilbert space,and can thus reduce the complexity of practical ***,we carry out corresponding numerical simulations and demonstrate that our present four-intensity decoy-state scheme can achieve a much higher key rate compared than a three-intensity decoy-state method,and meantime it can obtain a longer transmission distance compared than the one using weak coherent sources.

关键词： quantum key distribution heralded single-photon source decoy-state method

Astrocytic calcium waves:unveiling their roles in sleep and arousal modulation

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Neural Regeneration Research 2024年第5期19卷 984-987页

作者： Erxi Wu Dan Qi Damir Nizamutdinov Jason H.Huang Department of Neurosurgery and Neuroscience institute Baylor Scott&White HealthTempleTXUSA Texas A&M university School of Medicine TempleTXUSA Texas A&M university School of Pharmacy College StationTXUSA LIVESTRONG cancer institutes and Department of Oncology Dell Medical Schoolthe University of Texas at AustinAustinTXUSA Department of Neurosurgery Baylor College of MedicineTempleTXUSA

Neuron-astrocyte interactions are vital for the brain’s *** astrocyte activities is crucial for comprehending the complex neural network,particularly the population-level functions of neurons in different cortical states and associated behaviors in *** on animal sleep and wakefulness have revealed distinct cortical synchrony patterns between ***,outnumbering neurons by nearly fivefold,support and regulate neuronal and synaptic *** research on astrocyte activation during cortical state transitions has emphasized the influence of norepinephrine as a neurotransmitter and calcium waves as key components of ion channel *** summary focuses on a few recent studies investigating astrocyte-neuron interactions in mouse models during sleep,wakefulness,and arousal levels,exploring the involvement of noradrenaline signaling,ion channels,and glutamatergic signaling in different cortical *** findings highlight the significant impact of astrocytes on large-scale neuronal networks,influencing brain activity and *** astrocytic signaling pathways shows promise for treating sleep disorders and arousal *** research is needed to understand astrocytic calcium signaling in different brain regions and its implications for dysregulated brain states,requiring future human studies to comprehensively investigate neuron-astrocyte interactions and pave the way for therapeutic interventions in sleep-and arousal-related disorders.

关键词： arousal astrocyte calcium waves locus coeruleus neuron-astrocyte interaction norepinephrine sleep wakefulness

The First Verification Test of Space-Ground Collaborative Intelligence via Cloud-Native Satellites

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China Communications 2024年第4期21卷 208-217页

作者： Wang Shangguang Zhang Qiyang Xing Ruolin Qi Fei Xu Mengwei State Key Laboratory of networking and Switching Beijing University of Posts and TelecommunicationsBeijing 100876China Star network and Intelligent Computing Laboratory Beiyou Shenzhen InstituteShenzhen 518000China Huawei Technologies Co. LtdShenzhen 518129China

Recent advancements in satellite technologies and the declining cost of access to space have led to the emergence of large satellite constellations in Low Earth Orbit(LEO).However,these constellations often rely on bent-pipe architecture,resulting in high communication *** onboard inference architectures suffer from limitations in terms of low accuracy and inflexibility in the deployment and management of in-orbit *** address these challenges,we propose a cloud-native-based satellite design specifically tailored for Earth Observation tasks,enabling diverse computing *** this work,we present a case study of a satellite-ground collaborative inference system deployed in the Tiansuan constellation,demonstrating a remarkable 50%accuracy improvement and a substantial 90%data *** work sheds light on in-orbit energy,where in-orbit computing accounts for 17%of the total onboard energy *** approach represents a significant advancement of cloud-native satellite,aiming to enhance the accuracy of in-orbit computing while simultaneously reducing communication cost.

关键词： cloud-native satellite orbital edge computing satellite inference verification test

Recent progress on mechanisms,principles,and strategies for high-activity and high-stability non-PGM fuel cell catalyst design

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Carbon Energy 2024年第5期6卷 25-52页

作者： Yuping Yuan Yun Zheng Dan Luo Weibin Qiu Jiantao Wang Xin Wang Zhongwei Chen GRINM(Guangdong)institute of New Materials Technology FoshanChina Department of Chemical Engineering Waterloo Institute for NanotechnologyWaterloo Institute for Sustainable EnergyUniversity of WaterlooWaterlooOntarioCanada Guangdong Provincial Key Laboratory of Nanophotonic Functional Materials and Devices School of Information and Optoelectronic Science and EngineeringSouth China Normal UniversityGuangdongChina National Power Battery Innovation Center GRINM Group Co.Ltd.BeijingChina

The commercialization of a polymer membrane H2-O2 fuel cell and its widespread use call for the development of cost-effective oxygen reduction reaction(ORR)nonplatinum group metal(NPGM)***,to meet the requests for the real-world fuel cell application and replacing platinum catalysts,it still needs to address some challenges for NPGM catalysts regarding the sluggish ORR kinetics in the cathode and their poor durability in acidic *** response to these issues,numerous efforts have been made to study NPGM catalysts both theoretically and experimentally,developed these into the atomically dispersed coordinated metal-nitrogen-carbon(M-N-C)form over the past *** this review,we present a comprehensive summary of recent advancements on NPGM catalysts with high activity and *** design strategies in terms of optimizing active-site density and enhancing catalyst stability against demetalization and carbon corrosion are *** is also emphasized the importance of understanding the mechanisms and principles behind those strategies through a combination of theoretical modeling and experimental ***,further understanding the mechanisms related to the active-site structure and the formation process of the single-atom active site under pyrolysis conditions is critical for active-site *** the active-site distance is the basic principle for improving catalyst activity through increasing the catalyst active-site *** studies for the catalyst deactivation mechanism and modeling stable active-site structures provide both mechanisms and principles to improve the NPGM catalyst ***,currently remained challenges and perspectives in the future on designing high-performance atomically dispersed NPGM catalysts toward fuel cell application are discussed.

关键词： batteries electrocatalysis energy storage and conversion fuel cells

A Parallel-type Load Damping Factor Controller for Frequency Regulation in Power Systems with High Penetration of Renewable Energy Sources

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Journal of Modern Power Systems and Clean Energy 2024年第4期12卷 1019-1030页

作者： Zhe Zhang Siyang Liao Yuanzhang Sun Jian Xu Deping Ke Bo Wang Rui Chen Yibo Jiang Hubei Engineering and Technology Research Center for AC/DC Intelligent Distribution network School of Electrical Engineering and AutomationWuhan UniversityWuhan 430072China State Grid Hubei Electric Power Company Limited Economic Research institute Wuhan 430074China State Grid(Suzhou)City&Energy Research institute Company Limited Suzhou 215000China

Renewable energy sources(RESs)are rapidly devel-oping and their substitution for traditional power generation poses significant challenges to the frequency regulation in pow-er *** load damping factor D characterizes the active power of load that changes with power system frequency,which is an important factor influencing the frequency ***-ever,the value of D is small,resulting in the limitation in fre-quency regulation of the power *** paper proposes a parallel-type load damping factor controller to enhance load damping factor by utilizing static var generators(SVGs)in ***,it discusses the configuration method for the relevant parameters of the controller,evaluates its frequen-cy regulation capability,investigates the impact of large-scale application of the controller on static and dynamic loads,and conducts a comprehensive evaluation of the impact of the damp-ing factor control process on the voltage stability of the main *** large-scale application of the proposed controller can significantly improve the frequency regulation capability,and al-most have no influence on the working status of the *** can also significantly improve the dynamic performance of system *** proposed controller can provide technical sup-port for the frequency regulation of new power systems with high proportion of RESs.

关键词： Load damping factor parallel-type load damping factor controller power system frequency regulation highproportion renewable energy system

Current trends and hotspots of depressive disorders with colorectal cancer:A bibliometric and visual study

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World Journal of Gastrointestinal Oncology 2024年第8期16卷 3687-3704页

作者： Zi-Wei Yan Ying-Nan Liu Qian Xu Yuan Yuan Tumor Etiology and Screening Department of cancer institute and General Surgery The First Hospital of China Medical UniversityShenyang 110001Liaoning ProvinceChina Key Laboratory of cancer Etiology and Prevention in Liaoning Education Department The First Hospital of China Medical UniversityShenyang 110001Liaoning ProvinceChina Laboratory of GI cancer Etiology and Prevention in Liaoning Province The First Hospital of China Medical UniversityShenyang 110001Liaoning ProvinceChina

BACKGROUND Depression is strongly associated with colorectal cancer(CRC).Few bibliometric analyses have systematically summarized the research focus and recent progress in this *** To determine the research status and hotspots by bibliometric analysis of relevant publications on the relationship between CRC and *** Articles on depression in CRC patients were collected from the Web of Science Core *** and VOSviewer software were used to visualize bibliometric *** From 2001 to 2022,Supportive Care in cancer,the United States,Tilburg university,and Mols were the most productive and influential journal,country,institution,and author ***-occurrence cluster analysis of keywords placed quality of life,anxiety,and psychological stress in the center of the visual network *** clustering was performed for the clusters with studies of the relevant mechanism of action,which showed that:(1)Cytokines have a role essential for the occurrence and development of depressive disorders in CRC;(2)MicroRNAs have a role essential for the development of depressive disorders in CRC;(3)Some anticancer drugs have pro-depressant activity;and(4)Selective serotonin reuptake inhibitors have both antitumor and antidepressant *** Life quality and psychological nursing of the cancer population were key *** roles of cytokines and microRNAs,the pro-depression activity of anticancer drugs and their antitumor properties deserve in-depth study.

关键词： Depression Colorectal cancer Bibliometric analysis Cytokines Drugs Mechanism

Stackelberg Game for Wireless Powered and Backscattering Enabled Sensor networks

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China Communications 2024年第3期21卷 189-204页

作者： Lyu Bin Cao Yi Wang Shuai Guo Haiyan Hao Chengyao Key Laboratory of Ministry of Education in Broadband Wireless Communication and Sensor network Technology Nanjing University of Posts and TelecommunicationsNanjing 210003China Jiangsu Engineering Research Center of Novel Optical Fiber Technology and Communication network Suzhou 215006China Guangdong-Hong Kong-Macao Joint Laboratory of Human-Machine Intelligence-Synergy Systems Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China

This paper investigates a wireless powered and backscattering enabled sensor network based on the non-linear energy harvesting model, where the power beacon(PB) delivers energy signals to wireless sensors to enable their passive backscattering and active transmission to the access point(AP). We propose an efficient time scheduling scheme for network performance enhancement, based on which each sensor can always harvest energy from the PB over the entire block except its time slots allocated for passive and active information delivery. Considering the PB and wireless sensors are from two selfish service providers, we use the Stackelberg game to model the energy interaction among them. To address the non-convexity of the leader-level problem, we propose to decompose the original problem into two subproblems and solve them iteratively in an alternating manner. Specifically, the successive convex approximation, semi-definite relaxation(SDR) and variable substitution techniques are applied to find a nearoptimal solution. To evaluate the performance loss caused by the interaction between two providers, we further investigate the social welfare maximization problem. Numerical results demonstrate that compared to the benchmark schemes, the proposed scheme can achieve up to 35.4% and 38.7% utility gain for the leader and the follower, respectively.

关键词： backscatter communication energy interaction stackelberg game wireless powered sensor network