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Aparecium:understanding and detecting scam behaviors on Ethereum via biased random Walk

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Cybersecurity 2024年第3期7卷 16-31页

作者： Chuyi Yan Chen Zhang Meng Shen Ning Li Jinhao Liu Yinhao Qi Zhigang Lu Yuling Liu Institute of Information Engineering Chinese Academy of SciencesBeijing 100093China School of Cyber Security University of Chinese Academy of SciencesBeijing 100049China School of cyberspace Science and Technology Bejing Institute of TechnologyBeijing 100081China

Ethereum's high attention,rich business,certain anonymity,and untraceability have attracted a group of *** on it has become increasingly rampant,among which scam behavior is convenient,cryptic,antagonistic and resulting in large economic *** we consider the scam behavior on Ethereum and investigate it at the node interaction *** on the life cycle and risk identification points we found,we propose an automatic detection model named ***,a graph generation method which focus on the scam life cycle is adopted to mitigate the sparsity of the scam ***,the life cycle patterns are delicate modeled because of the crypticity and antagonism of Ethereum scam *** experiments in the wild Ethereum datasets,we prove Aparecium is effective which the precision,recall and F1-score achieve at 0.977,0.957 and 0.967 respectively.

关键词： Blockchain Network security Ethereum Scam detection Behavior understanding

The Structure Entropy of Social Networks

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Journal of Systems Science & Complexity 2024年第3期37卷 1147-1162页

作者： LI Zhenpeng YAN Zhihua YANG Jian TANG Xijin School of Electronics and Information Engineering Taizhou UniversityLinhai 317000China academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100190China Yunnan Key Laboratory of Smart City in cyberspace Security Yuxi Normal UniversityYuci 653100China University of chinese academy of Sciences Beijing 100039China

Micro triadic structure is an important motif and serves the building block of complex *** this paper,the authors define structure entropy for a social network and explain this concept by using the coded triads proposed by Davis and Leinhardt in *** proposed structure entropy serves as a new macro-evolution index to measure the network’s stability at a given *** analysis of real-world network structure entropy discloses rich information on the mechanism that yields given triadic motifs frequency *** paper illustrates the intrinsic link between the micro dyadic/triadic motifs and network structure ***,the authors find that the high proportion of reciprocity and transitivity results in the emergence of hierarchy,order,and cooperation of online social networks.

关键词： Dyadic and triadic motifs network structure entropy reciprocity and transitivity

A Generalized MSST Algorithm for Counting Points of Elliptic Curves over F_(p)^(n)

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Journal of Systems Science & Complexity 2024年第4期37卷 1738-1754页

作者： LI Xiao LV Chang PAN Zhizhong Key Laboratory of cyberspace Security Defense Institute of Information EngineeringChinese Academy of SciencesBeijing 100085China School of Cyber Security University of Chinese Academy of SciencesBeijing 100085China Huawei Technologies Co. Ltd.Shenzhen 518129China

Elliptic curve cryptography is an important part of nowaday's public key *** points of elliptic curves over finite fields is of great significance to the selection of safety *** present,there are many p-adic algorithms,such as SST algorithm,generalized AGM algorithm,Kedlaya algorithm,etc.,which can deal with the situation of finite fields of small *** this paper,the authors generalize the MSST algorithm of characteristic 2 to general fields of odd characteristic,and propose the generalized MSST *** generalized MSST algorithm is achieved by combining the advantages of the SST algorithm and the generalized AGM *** the time complexity of the multiplication of two n-bit numbers is denoted as O((n)^(μ)),then the time complexity of the generalized MSST algorithm is O(n^(2μ+1/1+μ)),which is the same as the improved SST *** practical experiments,the running time of the generalized MSST algorithm is less than that of the improved SST algorithm.

关键词： Elliptic curve generalized AGM algorithm generalized MSST algorithm SST algorithm

Evicting and filling attack for linking multiple network addresses of Bitcoin nodes

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Cybersecurity 2024年第3期7卷 49-68页

作者： Huashuang Yang Jinqiao Shi Yue Gao Xuebin Wang Yanwei Sun Ruisheng Shi Dongbin Wang School of cyberspace Security Bejing University of Posts and TelecommunicationsBeijingChina Tsinghua University Bejing 100084China Institute of Information Engineering Chinese Academy of SciencesBeijingChina

Bitcoin is a decentralized P2P *** supports users to use pseudonyms instead of network addresses to send and receive transactions at the data layer,hiding users'real network *** transaction tracing attack cuts through the network layer to directly associate each transaction with the network address that issued it,thus revealing the sender's network *** this attack can be mitigated by Bitcoin's network layer privacy *** Bitcoin protects the unlinkability of Bitcoin addresses and there may be a many-to-one relation-ship between addresses and nodes,transactions sent from the same node via different addresses are seen as com-ing from different nodes because attackers can only use addresses as node *** this paper,we proposed the evicting and flling attack to expose the correlations between addresses and cluster transactions sent from different addresses of the same *** attack exploited the unisolation of Bitcoin's incoming connection processing *** particular,an attacker can utilize the shared connection pool and deterministic connection eviction strategy to infer the correlation between incoming and evicting connections,as well as the correlation between releasing and flling *** on inferred results,different addresses of the same node with these connections can be linked together,whether they are of the same or different network *** designed a multi-step attack procedure,and set reasonable attack parameters through analyzing the factors that affect the attack effciency and *** mounted this attack on both our self-run nodes and multi-address nodes in real Bitcoin network,achieving an aver-age accuracy of 96.9% and 82%,***,we found that the attack is also applicable to Zcash,Litecoin,Dogecoin,Bitcoin Cash,and *** analyzed the cost of network-wide attacks,the application scenario,and proposed countermeasures of this attack.

关键词： Security and privacy Bitcoin Address linking

Label-Aware chinese Event Detection with Heterogeneous Graph Attention Network

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Journal of Computer Science & Technology 2024年第1期39卷 227-242页

作者：崔诗尧郁博文从鑫柳厅文谭庆丰时金桥 Institute of Information Engineering Chinese Academy of SciencesBeijing 100190China School of Cyber Security University of Chinese Academy of SciencesBeijing 100049China cyberspace Institute of Advanced Technology Guangzhou UniversityGuangzhou 510006China School of Cyber Security Beijing University of Posts and TelecommunicationsBeijing 100088China

Event detection(ED)seeks to recognize event triggers and classify them into the predefined event *** ED is formulated as a character-level task owing to the uncertain word *** methods try to incorpo-rate word-level information into characters to enhance their ***,they experience two ***,they fail to incorporate word-level information into each character the word encompasses,causing the insufficient word-charac-ter interaction ***,they struggle to distinguish events of similar types with limited annotated instances,which is called the event confusing *** paper proposes a novel model named Label-Aware Heterogeneous Graph Attention Network(L-HGAT)to address these two ***,we first build a heterogeneous graph of two node types and three edge types to maximally preserve word-character interactions,and then deploy a heterogeneous graph attention network to enhance the semantic propagation between characters and ***,we design a pushing-away game to enlarge the predicting gap between the ground-truth event type and its confusing counterpart for each *** results show that our L-HGAT model consistently achieves superior performance over prior competitive methods.

关键词： chinese event detection heterogeneous graph attention network(HGAT) label embedding

Recent advances and key perspectives of in-situ studies for oxygen evolution reaction in water electrolysis

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Green Energy & Environment 2024年第10期9卷 1497-1517页

作者： Yi Wang Zichen Xu Xianhong Wu Zhong-Shuai Wu State Key Laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences University of chinese academy of Sciences Shijingshan District Dalian National Laboratory for Clean Energy Chinese Academy of Sciences

Electricity-driven water splitting to produce hydrogen is one of the most efficient ways to alleviate energy crisis and environmental pollution problems, in which the anodic oxygen evolution reaction(OER) is the key half-reaction of performance-limiting in water splitting. Given the complicated reaction process and surface reconstruction of the involved catalysts under actual working conditions, unraveling the real active sites, probing multiple reaction intermediates and clarifying catalytic pathways through in-situ characterization techniques and theoretical calculations are essential. In this review, we summarize the recent advancements in understanding the catalytic process, unlocking the water oxidation active phase and elucidating catalytic mechanism of water oxidation by various in-situ characterization techniques. Firstly, we introduce conventionally proposed traditional catalytic mechanisms and novel evolutionary mechanisms of OER, and highlight the significance of optimal catalytic pathways and intrinsic stability. Next, we provide a comprehensive overview of the fundamental working principles,different detection modes, applicable scenarios, and limitations associated with the in-situ characterization techniques. Further, we exemplified the in-situ studies and discussed phase transition detection, visualization of speciation evolution, electronic structure tracking, observation of reaction active intermediates, and monitoring of catalytic products, as well as establishing catalytic structure–activity relationships and catalytic mechanism. Finally, the key challenges and future perspectives for demystifying the water oxidation process are briefly proposed.

关键词： In-situ studies Water splitting Oxygen evolution reaction Catalytic mechanism

The influence of silica on reaction rates and molecular hydrogen(H_(2))generation during olivine hydrothermal alteration

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Science China Earth Sciences 2024年第1期67卷 222-233页

作者： Ruifang HUANG Weidong SUN Xing DING Yusheng ZHAO Yibing LI Xiuqi SHANG CAS Key Laboratory of Ocean and Marginal Sea Geology South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China SUSTech academy for Advanced Interdisciplinary studies Southern University of Science and TechnologyShenzhen 518055China Center of Deep Sea Research Institute of OceanologyChinese Academy of SciencesQingdao 266071China State Key Laboratory of Isotope Geochemistry Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China Institue of Geology Chinese Academy of Geological SciencesBeijing 100037China

Hydrothermal alteration of olivine greatly influences geodynamics and the recycling of volatiles(such as water and carbon)in subduction *** is an important component of geological fluids,and its influence on the hydrothermal alteration of olivine remains poorly *** this study,we performed experiments at 300–515℃ and 3.0 kbar(1 bar=10^(5)Pa)by reacting well homogenized mixtures of olivine and silica powders with saline solutions(0.5 mol L^(−1)NaCl).Silica greatly influences the reaction pathways,reaction rates,and molecular hydrogen(H_(2))formation during olivine hydrothermal *** experiments at 300℃ and 3.0 kbar with mixtures of olivine and 10 wt%silica,olivine was replaced by serpentine and *** proportions of serpentine and talc were determined according to standard curves based on infrared spectroscopy *** 6.5%serpentine and 12%talc were produced after an experimental duration of 7 days,which had no change after a longer period(14 days).Compared to the kinetics in silica-free systems,the rates of olivine hydrothermal alteration in experiments with 10 wt%silica are much *** overall reaction is:4.5Forsterite+5.5SiO_(2),aq+4H_(2)O=Serpentine+*** the addition of more silica(20 wt%and 40 wt%),olivine was transformed into *** rates of reaction were much faster,e.g.,for experiments with olivine and 20 wt%silica,43%of talc was produced after 14 days,which increased to 77%for experiments with 40 wt%silica over the same *** overall reaction is:3Forsterite+5SiO_(2),aq+2H_(2)O=*** experiments at 400–505℃ and 3.0 kbar,the promoting effect of silica on olivine hydrothermal alteration was also observed,which is closely associated with a decrease in Gibbs free energies of olivine hydrothermal *** 300℃ and 3.0 kbar,silica decreased H_(2)formed during olivine hydrothermal alteration by around an order of magnitude,resulting in an increase in oxygen *** on measured H_(2),we calibrated ox

关键词： Olivine hydrothermal alteration Silica Serpentinization Hydrogen Serpentine

Changes in extreme high temperature warning indicators over China under different global warming levels

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Science China Earth Sciences 2024年第6期67卷 1895-1909页

作者： Yuxia ZHANG Ying SUN Ting HU chinese academy of Meteorological Sciences Beijing 100081China National Climate Center Laboratory for Climate StudiesChina Meteorological AdministrationBeijing 100081China

High temperature warning indicators play a pivotal role in meteorological departments,serving as crucial criteria for issuing warnings that guide both social production and daily *** their importance,limited studies have explored the relationship between different global warming levels and changes in high temperature warning *** this study,we analyze data from 2,419 meteorological stations over China and utilize the Coupled Model Intercomparison Project Phase 6(CMIP6)models to examine historical changes in high temperature warning indicators used by the China Meteorological *** evaluate model performance and estimate future changes in these indicators using an annual cycle bias correction *** results indicate that since 1961,the number of high temperature days(TX35d and TX40d)and length of season(TX40d and TX40l)with daily maximum temperature reaching or exceeding 35℃ and 40℃ have increased over *** intensity of high temperatures(TXx)has strengthened and the geographical extent affected by high temperatures has *** 2022,the occurrence of 40℃ high temperatures surges,with Eastern China experiencing a two-day increase in TX40d and an extended seasonal length in TX40l by over five *** CMIP6 models have underestimated the high temperature indictors associated with 35℃ during historical periods,notable difference is not observed between the models and observations for TX40d and TX40l,given their rare ***,future projections,after bias correction,indicate that the increasing trends for 35℃ and 40℃ high temperature days and length of season become more pronounced than the raw projection,suggesting a more severe increase than that anticipated *** global warming intensifies,the high temperature days and length of season are projected to increase non-linearly,while the intensity of high temperatures is expected to increase *** every 1℃ increase in global temperature,the intensity is

关键词： Extreme high temperatures Meteorological warning CMIP6 Global warming levels Future projection

Equilibrium Strategy of the Pursuit-Evasion Game in Three-Dimensional Space

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IEEE/CAA Journal of Automatica Sinica 2024年第2期11卷 446-458页

作者： Nuo Chen Linjing Li Wenji Mao School of Artificial Intelligence University of Chinese Academy of SciencesBeijing 100049 Institute of Automation Chinese Academy of SciencesBeijing 100190China

The pursuit-evasion game models the strategic interaction among players, attracting attention in many realistic scenarios, such as missile guidance, unmanned aerial vehicles, and target defense. Existing studies mainly concentrate on the cooperative pursuit of multiple players in two-dimensional pursuit-evasion games. However, these approaches can hardly be applied to practical situations where players usually move in three-dimensional space with a three-degree-of-freedom control. In this paper,we make the first attempt to investigate the equilibrium strategy of the realistic pursuit-evasion game, in which the pursuer follows a three-degree-of-freedom control, and the evader moves freely. First, we describe the pursuer's three-degree-of-freedom control and the evader's relative coordinate. We then rigorously derive the equilibrium strategy by solving the retrogressive path equation according to the Hamilton-Jacobi-Bellman-Isaacs(HJBI) method, which divides the pursuit-evasion process into the navigation and acceleration phases. Besides, we analyze the maximum allowable speed for the pursuer to capture the evader successfully and provide the strategy with which the evader can escape when the pursuer's speed exceeds the threshold. We further conduct comparison tests with various unilateral deviations to verify that the proposed strategy forms a Nash equilibrium.

关键词： Differential game equilibrium strategy pursuit-evasion game threedegree-of-freedom control