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BulkTree: an overlay network architecture for live media streaming

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第z1期7卷 125-130页

作者： GONG An DING Gui-guang dai qiong-hai lin Chuang Department of Computer Science & Technology Tsinghua University Beijing 100084 China Broadband Networks & Digital Media Laboratory Department of Automation Tsinghua University Beijing 100084 China Broadband Networks & Digital Media Laboratory Department of Automation Tsinghua University Beijing 100084 China Department of Computer Science & Technology Tsinghua University Beijing 100084 China

Peer-to-peer (P2P) systems are now very popular. Current P2P systems are broadly of two kinds, structured and unstructured. The tree structured P2P systems used technologies such as distributed hash tables (DHT) and hierarchical clustering can search the required target quickly, however, in a tree, the internal node has a higher load and its leave or crash often causes a large population of its offspring's problems, so that in the highly dynamic Internet environment the tree structure may still suffer frequent breaks. On the other hand, most widely used unstructured P2P networks rely on central directory servers or massive message flooding, clearly not scalable. So, we consider both of the above systems' advantages and disadvantages and realize that in the P2P systems one node may fail easily, but that when a number of nodes organized as a set, which we call "super node", the set is robust. Super nodes can be created and updated aware of topology-aware, and used with simple protocol such as flooding or "servers" to exchange information. Furthermore the entire robust super node can be organized into exquisite tree structure. By using this overlay network architecture, P2P systems are robust, efficient, scalable and secure. The simulation results demonstrated that our architecture greatly reduces the alteration time of the structure while decreasing the average delay time, compared to the common tree structure.

关键词： Peer-to-peer (P2P), Overlay networks, Scalability, Live media, Distributed hash tables (DHT), Hierarchical clustering

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Optimal Cooperation Enhancement on Spatial Networks

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Chinese Physics Letters 2014年第11期31卷 1-4页

作者： Tao Shui-Yuan Cui Ming-Zhu dai qiong-lin Yang Jun-Zhong Beijing Univ Posts & Telecommun Sch Sci Beijing 100876 Peoples R China

We investigate the evolutionary Prisoner＇s dilemma game on the simplest spatial networks constructed as geometrical graphs. The optimal cooperation enhancement against the topology randomness is found. It is proposed that the optimal behavior of the cooperation results from the competition between individuals with high degrees and with low degrees： the former assists the formation of cooperator clusters and the latter tends to prevent the formation of such dusters.

关键词： TOPOLOGY PRISONER'S dilemma game PHYSICS research SELFISHNESS COEVOLUTION

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Engineering atomic Rb-N configurations to tune radical pathways for highly selective photocatalytic H2O2 synthesis coupled with biomass valorization

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Journal of Energy Chemistry 2025年第1期100卷 215-225页

作者： Jiaye Li Shuang Pan Yihuang Chen qiong Liu College of Chemistry and Materials Engineering Wenzhou University Guangdong Provincial Key Laboratory of Chemical Measurement and Emergency Test Technology (China) Institute of Analysis Guangdong Academy of Sciences (China National Analytical CenterGuangzhou)

Photocatalytic oxygen reduction for hydrogen peroxide （H2O2） synthesis presents a green and costeffective production ***,achieving highly selective H2O2synthesis remains challenging,necessitating precise control over free radical reaction pathways and minimizing undesirable oxidative ***,we report for the visible light-driven simultaneous co-photocatalytic reduction of O2to H2O2and oxidation of biomass using the atomic rubidium-nitride modified carbon nitride（CNRb）.The optimized CNRb catalyst demonstrates a record photoreduction rate of 8.01 mM h-1for H2O2generation and photooxidation rate of 3.75 mM h-1for furfuryl alcohol to furoic acid,achieving a remarkable solar-to-chemical conversion （SCC） efficiency of up to 2.27%.Experimental characterizations and DFT calculation disclosed that the introducing atomic Rb–N configurations allows for the high-selective generation of superoxide radicals while suppressing hydroxyl free radical *** is because the Rb–N serves as the new alternative site to perceive a stronger connection position for O2adsorption and reinforce the capability to extract protons,thereby triggering a high selective redox product *** study holds great potential in precisely regulating reactive radical processes at the atomic level,thereby paving the way for efficient synthesis of H2O2coupled with biomass valorization.

关键词： Atomic economy Radical pathway regulation Rubidium atom coordination Biomass valorization

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一种简单的基于蔡氏电路的数字加密通信实验

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大学物理 2006年第9期25卷 39-42页

作者：李海红代琼琳王世红肖井华北京邮电大学理学院北京100876

介绍一种简单的基于蔡氏电路的对数字信号进行加密传输以及解密的实验方法,以及该实验作为一个新的与前沿科学相结合的普通物理实验的优点.

关键词：混沌同步加密通信蔡氏电路

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Brain region-specific roles of brain-derived neurotrophic factor in social stress-induced depressive-like behavior

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Neural Regeneration Research 2025年第1期20卷 159-173页

作者： Man Han Deyang Zeng Wei Tan Xingxing Chen Shuyuan Bai qiong Wu Yushan Chen Zhen Wei Yufei Mei Yan Zeng Brain Science and Advanced Technology Institute Wuhan University of Science and TechnologyWuhanHubei ProvinceChina Geriatric Hospital Affiliated to Wuhan University of Science and Technology WuhanHubei ProvinceChina School of Public Health Wuhan University of Science and TechnologyWuhanHubei ProvinceChina

Brain-derived neurotrophic factor is a key factor in stress adaptation and avoidance of a social stress behavioral *** studies have shown that brain-derived neurotrophic factor expression in stressed mice is brain region–specific,particularly involving the corticolimbic system,including the ventral tegmental area,nucleus accumbens,prefrontal cortex,amygdala,and *** how brain-derived neurotrophic factor participates in stress processing in different brain regions will deepen our understanding of social stress *** this review,we discuss the expression and regulation of brain-derived neurotrophic factor in stress-sensitive brain regions closely related to the pathophysiology of *** focused on associated molecular pathways and neural circuits,with special attention to the brain-derived neurotrophic factor–tropomyosin receptor kinase B signaling pathway and the ventral tegmental area–nucleus accumbens dopamine *** determined that stress-induced alterations in brain-derived neurotrophic factor levels are likely related to the nature,severity,and duration of stress,especially in the above-mentioned brain regions of the corticolimbic ***,BDNF might be a biological indicator regulating stress-related processes in various brain regions.

关键词： amygdala chronic mild stress chronic social defeat stress corticolimbic system depression hippocampus medial prefrontal cortex nucleus accumbens social stress models ventral tegmental area

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混沌通信实验仪及应用软件

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物理实验 2012年第7期32卷 13-16页

作者：蒋达娅杨胡江代琼琳肖井华北京邮电大学理学院北京100876

介绍了混沌通信实验仪的5组基本构成模块,通过模块式的组合,可以实现对混沌电路及混沌同步特点的观察和研究.该实验仪可以通过混沌掩盖的加密方法对模拟信号进行加密,也可以用混沌键控的方法对数字信号进行加密.

关键词：混沌通信混沌加密应用软件

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Research status and prospects of the fractal analysis of metal material surfaces and interfaces

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 20-38页

作者： Qinjin dai Xuefeng Liu Xin Ma Shaojie Tian Qinghe Cui Beijing Advanced Innovation Center for Materials Genome Engineering University of Science and Technology BeijingBeijing 100083China Beijing Laboratory of Metallic Materials and Processing for Modern Transportation University of Science and Technology BeijingBeijing 100083China Laboratory for Advanced Materials Processing of Ministry of Education University of Science and Technology BeijingBeijing 100083China School of Mechanical and Electrical Engineering Xinjiang Institute of EngineeringUrumqi 830023China

As a mathematical analysis method,fractal analysis can be used to quantitatively describe irregular shapes with self-similar or self-affine *** analysis has been used to characterize the shapes of metal materials at various scales and *** methods make it difficult to quantitatively describe the relationship between the regular characteristics and properties of metal material surfaces and ***,fractal analysis can be used to quantitatively describe the shape characteristics of metal materials and to establish the quantitative relationships between the shape characteristics and various properties of metal *** the perspective of two-dimensional planes and three-dimensional curved surfaces,this paper reviews the current research status of the fractal analysis of metal precipitate interfaces,metal grain boundary interfaces,metal-deposited film surfaces,metal fracture surfaces,metal machined surfaces,and metal wear *** relationship between the fractal dimensions and properties of metal material surfaces and interfaces is *** from three perspectives of fractal analysis,namely,research scope,image acquisition methods,and calculation methods,this paper identifies the direction of research on fractal analysis of metal material surfaces and interfaces that need to be *** is believed that revealing the deep influence mechanism between the fractal dimensions and properties of metal material surfaces and interfaces will be the key research direction of the fractal analysis of metal materials in the future.

关键词： metal material surfaces and interfaces fractal analysis fractal dimension homogeneity

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SensFL:Privacy-Preserving Vertical Federated Learning with Sensitive Regularization

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 385-404页

作者： Chongzhen Zhang Zhichen Liu Xiangrui Xu Fuqiang Hu Jiao dai Baigen Cai Wei Wang School of Automation and Intelligence Beijing Jiaotong UniversityBeijing100044China Shuohuang Railway Development Co. Ltd.National Energy GroupCangzhou062350China Beijing Key Laboratory of Security and Privacy in Intelligent Transportation School of Computer Science and TechnologyBeijing Jiaotong UniversityBeijing100044China

In the realm of Intelligent Railway Transportation Systems,effective multi-party collaboration is crucial due to concerns over privacy and data *** Federated Learning(VFL)has emerged as a promising approach to facilitate such collaboration,allowing diverse entities to collectively enhance machine learning models without the need to share sensitive training ***,existing works have highlighted VFL’s susceptibility to privacy inference attacks,where an honest but curious server could potentially reconstruct a client’s raw data from embeddings uploaded by the *** vulnerability poses a significant threat to VFL-based intelligent railway transportation *** this paper,we introduce SensFL,a novel privacy-enhancing method to against privacy inference attacks in ***,SensFL integrates regularization of the sensitivity of embeddings to the original data into the model training process,effectively limiting the information contained in shared *** reducing the sensitivity of embeddings to the original data,SensFL can effectively resist reverse privacy attacks and prevent the reconstruction of the original data from the *** experiments were conducted on four distinct datasets and three different models to demonstrate the efficacy of *** results show that SensFL can effectively mitigate privacy inference attacks while maintaining the accuracy of the primary learning *** results underscore SensFL’s potential to advance privacy protection technologies within VFL-based intelligent railway systems,addressing critical security concerns in collaborative learning environments.

关键词： Vertical federated learning privacy defenses

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A fast forward computational method for nuclear measurement using volumetric detection constraints

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Nuclear Science and Techniques 2024年第2期35卷 47-63页

作者： qiong Zhang lin-Lv lin University of Electronic Science and Technology of China Chengdu 610000China

Owing to the complex lithology of unconventional reservoirs,field interpreters usually need to provide a basis for interpretation using logging simulation *** the various detection tools that use nuclear sources,the detector response can reflect various types of information of the *** Monte Carlo method is one of the primary methods used to obtain nuclear detection responses in complex ***,this requires a computational process with extensive random sampling,consumes considerable resources,and does not provide real-time response ***,a novel fast forward computational method(FFCM)for nuclear measurement that uses volumetric detection constraints to rapidly calculate the detector response in various complex environments is ***,the data library required for the FFCM is built by collecting the detection volume,detector counts,and flux sensitivity functions through a Monte Carlo ***,based on perturbation theory and the Rytov approximation,a model for the detector response is derived using the flux sensitivity function method and a one-group diffusion *** environmental perturbation is constrained to optimize the model according to the tool structure and the impact of the formation and borehole within the effective detection ***,the method is applied to a neutron porosity tool for *** various complex simulation environments,the maximum relative error between the calculated porosity results of Monte Carlo and FFCM was 6.80%,with a rootmean-square error of 0.62 *** field well applications,the formation porosity model obtained using FFCM was in good agreement with the model obtained by interpreters,which demonstrates the validity and accuracy of the proposed method.

关键词： Nuclear measurement Fast forward computation Volumetric constraints

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Establishment of human cerebral organoid systems to model early neural development and assess the central neurotoxicity of environmental toxins

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Neural Regeneration Research 2025年第1期20卷 242-252页

作者： daiyu Hu Yuanqing Cao Chenglin Cai Guangming Wang Min Zhou Luying Peng Yantao Fan qiong Lai Zhengliang Gao Fundamental Research Center Shanghai Yangzhi Rehabilitation Hospital(Shanghai Sunshine Rehabilitation Center)School of MedicineTongji UniversityShanghaiChina Institute of Geriatrics(Shanghai University) Affiliated Nantong Hospital of Shanghai University(The Sixth People’s Hospital of Nantong)Shanghai University School of MedicineNantongJiangsu ProvinceChina Shanghai Engineering Research Center of Organ Repair Shanghai University School of MedicineShanghaiChina Key Laboratory of Arrhythmias Ministry of EducationShanghai East HospitalSchool of MedicineTongji UniversityShanghaiChina

Human brain development is a complex process,and animal models often have significant *** address this,researchers have developed pluripotent stem cell-derived three-dimensional structures,known as brain-like organoids,to more accurately model early human brain development and *** enable more consistent and intuitive reproduction of early brain development,in this study,we incorporated forebrain organoid culture technology into the traditional unguided method of brain organoid *** involved embedding organoids in matrigel for only 7 days during the rapid expansion phase of the neural epithelium and then removing them from the matrigel for further cultivation,resulting in a new type of human brain organoid *** cerebral organoid system replicated the temporospatial characteristics of early human brain development,including neuroepithelium derivation,neural progenitor cell production and maintenance,neuron differentiation and migration,and cortical layer patterning and formation,providing more consistent and reproducible organoids for developmental modeling and toxicology *** a proof of concept,we applied the heavy metal cadmium to this newly improved organoid system to test whether it could be used to evaluate the neurotoxicity of environmental *** organoids exposed to cadmium for 7 or 14 days manifested severe damage and abnormalities in their neurodevelopmental patterns,including bursts of cortical cell death and premature *** exposure caused progressive depletion of neural progenitor cells and loss of organoid integrity,accompanied by compensatory cell proliferation at ectopic *** convenience,flexibility,and controllability of this newly developed organoid platform make it a powerful and affordable alternative to animal models for use in neurodevelopmental,neurological,and neurotoxicological studies.

关键词： cadmium cell death cell proliferation cortical development environmental toxins neural progenitor cells neurogenesis neurotoxicology organoids stem cells

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