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High-Confidence Computing 2024年第3期4卷 64-74页

作者： Chao Wang Xueqiao Xu ke Xiao Yunhua he Guangcan Yang School of Information Science and Technology North China University of TechnologyBeijing 100144North China University of TechnologyBeijing 100144

Recently,vehicles have experienced a rise in networking and informatization,leading to increased security *** the most widely used automotive bus network,the Controller Area Network(CAN)bus is vulnerable to attacks,as security was not considered in its original *** paper proposes SIDuBzip2,a traffic anomaly detection method for the CAN bus based on the bzip2 compression *** proposed method utilizes the pseudo-periodic characteristics of CAN bus traffic,constructing time series of CAN IDs and calculating the similarity between adjacent time series to identify abnormal *** method consists of three parts:the conversion of CAN ID values to characters,the calculation of similarity based on bzip2 compression,and the optimal solution of model *** experimental results demonstrate that the proposed SIDuBzip2 method effectively detects various attacks,including Denial of Service,replay,basic injection,mixed injection,and suppression *** addition,existing CAN bus traffic anomaly detection methods are compared with the proposed method in terms of performance and delay,demonstrating the feasibility of the proposed method.

关键词： Automotive safety CAN bus Anomaly detection

Review on Security Defense Technology Research in Edge Computing Environment

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Chinese Journal of Electronics 2024年第1期33卷 1-18页

作者： ke SHANG Weizhen he Shuai ZHANG National Digital Switching System Engineering and Technological R&D Center

Edge computing, which achieves quick data processing by sinking data computing and storage to the network edge, has grown rapidly along with the Internet of things. The new network architecture of edge computing brings new security challenges. Based on this, this paper investigates the edge computing security literature published in recent years and summarizes and analyzes research work on edge computing security from different attack surfaces. We start with the definition and architecture of edge computing. From the attack surface between device and edge server, as well as on edge servers, the research describes the security threats and defense methods of edge computing. In addition, the cause of the attack and the pros and cons of defense methods is introduced. The challenges and future research directions of edge computing are given.

关键词： Cloud computing Systems architecture Computer architecture Network architecture Data processing Security Servers

Management of primary small cell carcinoma of the esophagus

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Chinese Medical Journal 2007年第5期120卷 355-358页

作者： SUN ke-lin he Jie CheNG Gui-yu CHAI Li-xun Department of Thoracic Surgery Cancer Institute and Hospital Chinese Academy of Medical Sciences Peking Union Medical College Beijing 100021 China

Background Primary small cell carcinoma of the esophagus is rare. Although surgery is successful in eradicating local tumor, the five-year survival rate of patients with primary small cell carcinoma of the esophagus after resection is lower than that of patients with primary squamous cell carcinoma of the esophagus. The purpose of this study was to analyze the clinical manifestations, pathological features and treatment of primary small cell carcinoma of the esophagus. Methods A total of 73 patients with primary small cell carcinoma of the esophagus who had been treated by surgery from 1984 to 2003 were analyzed retrospectively. Results In this series, the overall resection rate was 94.5% （69/73）, the radical resection rate 89.0% （65/73） and the operative mortality 1.4% （1/73）. The 1-, 3- and 5-year survival rates of patients were 50.7%, 13.7% and 8.2%, respectively. Conclusions Primary small cell carcinoma of the esophagus is rare with a poor prognosis. Surgical resection is the leading method for patients with stage Ⅰ or Ⅱ primary small cell carcinoma of the esophagus. Postoperative chemotherapy is beneficial to these patients. The patients of stage Ⅲ or IV should be given chemotherapy and radiation therapy.

关键词： esophagus small cell carcinoma surgery

Study of primordial deuterium abundance in Big Bang nucleosynthesis

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Nuclear Science and Techniques 2024年第3期35卷 208-215页

作者： Zhi-lin Shen Jian-Jun he key Laboratory of Beam Technology of Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Institute of Radiation Technology Beijing Academy of Science and TechnologyBeijing 100875China

Big Bang nucleosynthesis(BBN)theory predicts the primordial abundances of the light elements^(2) H(referred to as deuterium,or D for short),^(3)he,^(4)he,and^(7) Li produced in the early *** these,deuterium,the first nuclide produced by BBN,is a key primordial material for subsequent *** date,the uncertainty in predicted deuterium abundance(D/H)remains larger than the observational *** this study,the Monte Carlo simulation code PRIMAT was used to investigate the sensitivity of 11 important BBN reactions to deuterium *** found that the reaction rate uncertainties of the four reactions d(d,n)^(3)he,d(d,p)t,d(p,γ)^(3)he,and p(n,γ)d had the largest influence on the calculated D/H ***,the calculated D/H uncertainty cannot reach observational precision even with the recent LUNA precise d(p,γ)^(3) he *** the nuclear physics aspect,there is still room to largely reduce the reaction-rate uncertainties;hence,further measurements of the important reactions involved in BBN are still necessary.A photodisintegration experiment will be conducted at the Shanghai Laser Electron Gamma Source Facility to precisely study the deuterium production reaction of p(n,γ)d.

关键词： Big Bang nucleosynthesis Abundance of deuterium Reaction cross section Reaction rate Monte Carlo method

The Minimum Centroid Branch Spanning Tree Problem

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Journal of the Operations Research Society of China 2024年第2期12卷 528-539页

作者： Hao lin Cheng he School of Science Henan University of TechnologyZhengzhou450001HenanChina

For a spanning tree T of graph G,the centroid of T is a vertex v for which the largest component of T-v has as few vertices as *** number of vertices of this component is called the centroid branch weight of *** minimum centroid branch spanning tree problem is to find a spanning tree T of G such that the centroid branch weight is *** application to design of communication networks,the loads of all branches leading from the switch center should be as balanced as *** this paper,we prove that the problem is strongly NP-hard even for bipartite ***,the problem is shown to be polynomially solvable for split graphs,and exact formulae for special graph familis,say Kn_(1),n_(2),...,n_(k)and P_(m)×P_(n),are presented.

关键词： Spanning tree optimization Centroid branch-NP-hardness Polynomial-time algorithm

Construction of algal-bacterial consortia using green microalgae Chlorella vulgaris and As(Ⅲ)-oxidizing bacteria:As tolerance and metabolomic profiling

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Journal of Environmental Sciences 2024年第5期139卷 258-266页

作者： Xiaoman he Guobing lin Jiayuan Zeng Zhaoguang Yang lin Wang College of Chemistry and Chemical Engineering Central South UniversityChangsha 410083China key Laboratory of Hunan Province for Water Environment and Agriculture Product Safety Central South UniversityChangsha 410083China

Bioremediation became a promising technology to resolve arsenic(As)contamination in aquatic *** monoculture such as microalgae or bacteria was sensitive to environmental disturbance and vulnerable to contamination,green microalgae Chlorella vulgaris and arsenite(As(Ⅲ))-oxidizing bacteria Pseudomonas ***11 were co-cultured to construct algal-bacterial consortia in the current *** effects of algae-bacteria(A:B)ratio and exposure As(Ⅲ)concentration on algal growth,As speciation and metabolomic profile were *** growth arrested when treated with 100 mg/L As(Ⅲ)without the co-cultured *** contrast,co-cultured with strain SMS11 significantly enhanced As tolerance in *** especially with A:B ratio of 1:*** the As(Ⅲ)in culture media of the consortia were oxidized into As(Ⅴ)on day *** of As was observed on day *** 1% and 0.5% of total As were converted into dimethylarsinic acid(DMA)after 21days cultivation when the initial concentrations of As(Ⅲ)were 1 and 10 mg/L,*** analysis was further performed to reveal the response of consortia metabolites to external As(Ⅲ).The enriched metabolomic pathways were associated with carbohydrate,amino acid and energy *** acid cycle and glyoxylate and dicarboxylate metabolism were upregulated under As stress due to their biological functions on alleviating oxidative stress and protecting *** carbohydrate and amino acid metabolisms provided precursors and potential substrates for energy production and cell protection under abiotic *** of the pathways relevant to carbohydrate or amino acid metabolism were triggered by energy requirement.

关键词： Microalgae Algal-bacterial consortia As(Ⅲ)-oxidizing bacteria Metabolomics Energy metabolism

Smart Contract Vulnerability Detection Method Based on Feature Graph and Multiple Attention Mechanisms

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Computers, Materials & Continua 2024年第5期79卷 3023-3045页

作者： Zhenxiang he Zhenyu Zhao ke Chen Yanlin Liu School of Cyber Security Gansu University of Political Science and LawLanzhou730070China

The fast-paced development of blockchain technology is ***,the security concerns of smart contracts represent a significant challenge to the stability and dependability of the entire blockchain *** smart contract vulnerability detection primarily relies on static analysis tools,which are less efficient and *** deep learning methods have improved detection efficiency,they are unable to fully utilize the static relationships within ***,we have adopted the advantages of the above two methods,combining feature extraction mode of tools with deep learning ***,we have constructed corresponding feature extraction mode for different vulnerabilities,which are used to extract feature graphs from the source code of smart ***,the node features in feature graphs are fed into a graph convolutional neural network for training,and the edge features are processed using a method that combines attentionmechanismwith gated ***,the revised node features and edge features are concatenated through amulti-head *** result of the splicing is a global representation of the entire feature *** method was tested on three types of data:Timestamp vulnerabilities,reentrancy vulnerabilities,and access control vulnerabilities,where the F1 score of our method reaches 84.63%,92.55%,and 61.36%.The results indicate that our method surpasses most others in detecting smart contract vulnerabilities.

关键词： Blockchain smart contracts deep learning graph neural networks

Selective N-Methylation of N-Methylaniline with CO_(2) and H_(2) over Cu/In_(2)O_(3) Catalyst

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Chinese Journal of Chemistry 2024年第3期42卷 276-282页

作者： Huan Zheng Bo Qian lin he State key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhouGansu730000 China University of Chinese Academy of Sciences Beijing100049 China

N-Methylation of amines with CO_(2) and H2 is a potential approach for CO_(2) utilization because N-methylated amines can be used as solvents and organic intermediates. In_(2)O_(3)-supported Cu (Cu/In_(2)O_(3)) acts as an effective heterogeneous catalyst for N-methylation reaction of N-methylaniline (MA) with CO_(2) and H_(2),showing higher N,N-dimethylaniline (DMA) selectivity than other supported Cu catalysts. On one hand,the dispersion of Cu can be improved by the defective In_(2)O_(3) support. On the other hand,In_(2)O_(3) support is active in the dissociative adsorption of CO_(2) through C—O bond breaking. In addition,the H_(2) dissociation ability of In_(2)O_(3) can also be enhanced by Cu. The combination of Cu and In_(2)O_(3) is effective in the activation of CO_(2),the adsorption of intermediate N-methylformanilide (MFA),the hydrogenation of MFA to DMA and the prohibition of C—N bond cleavage side reactions,thereby enhancing the reaction rate of MA conversion and the selectivity to DMA.

关键词： N-Methylation CO_(2) Cu/In_(2)O_(3) Supported catalysts heterogeneous catalysis

Ballistic performances of the hourglass lattice sandwich structures under high-velocity fragments

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Defence Technology（防务技术） 2024年第1期31卷 312-325页

作者： he-xiang Wu Jia Qu lin-zhi Wu key Laboratory of Advanced Ship Materials and Mechanics College of Aerospace and Civil EngineeringHarbin Engineering UniversityHarbin150001China School of Civil Engineering Northeast Forestry UniversityHarbin150040China

In this paper,the numerical simulation method is used to study the ballistic performances of hourglass lattice sandwich structures with the same mass under the vertical incidence of *** is paid to elucidating the influences of rod cross-section dimensions,structure height,structure layer,and rod inclination angle on the deformation mode,ballistic performances,and ability to change the ballistic direction of *** results show that the ballistic performances of hourglass lattice sandwich structures are mainly affected by their structural *** this respect,structural parameters optimization of the hourglass lattice sandwich structures enable one to effectively improve their ballistic limit velocity and,consequently,ballistic performances.

关键词： Hourglass lattice sandwich structures Ballistic performances high-velocity Finite element analysis

Projecting Wintertime Newly Formed Arctic Sea Ice through Weighting CMIP6 Model Performance and Independence

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Advances in Atmospheric Sciences 2024年第8期41卷 1465-1482页

作者： Jiazhen ZHAO Shengping he ke FAN Huijun WANG Fei LI key Laboratory of Meteorological Disaster Ministry of Education/Joint International Research Laboratory of Climate and Environment Change(ILCEC)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD)Nanjing University of Information Science&TechnologyNanjing 210044China Geophysical Institute University of Bergen and Bjerknes Centre for Climate ResearchBergen 5007Norway School of Atmospheric Science Sun Yat-sen Universityand Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)Zhuhai 519082China Nansen Environmental and Remote Sensing Center and Bjerknes Centre for Climate Research Bergen 5007Norway Nansen-Zhu International Research Center Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519082China

Precipitous Arctic sea-ice decline and the corresponding increase in Arctic open-water areas in summer months give more space for sea-ice growth in the subsequent cold seasons. Compared to the decline of the entire Arctic multiyear sea ice,changes in newly formed sea ice indicate more thermodynamic and dynamic information on Arctic atmosphere–ocean–ice interaction and northern mid–high latitude atmospheric teleconnections. here, we use a large multimodel ensemble from phase 6 of the Coupled Model Intercomparison Project(CMIP6) to investigate future changes in wintertime newly formed Arctic sea ice. The commonly used model-democracy approach that gives equal weight to each model essentially assumes that all models are independent and equally plausible, which contradicts with the fact that there are large interdependencies in the ensemble and discrepancies in models' performances in reproducing observations. Therefore, instead of using the arithmetic mean of well-performing models or all available models for projections like in previous studies, we employ a newly developed model weighting scheme that weights all models in the ensemble with consideration of their performance and independence to provide more reliable projections. Model democracy leads to evident bias and large intermodel spread in CMIP6 projections of newly formed Arctic sea ice. However, we show that both the bias and the intermodel spread can be effectively reduced by the weighting scheme. Projections from the weighted models indicate that wintertime newly formed Arctic sea ice is likely to increase dramatically until the middle of this century regardless of the emissions ***, it may decrease(or remain stable) if the Arctic warming crosses a threshold(or is extensively constrained).

关键词： wintertime newly formed Arctic sea ice model democracy model weighting scheme model performance model independence