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Cybersecurity Named Entity Recognition Using Bidirectional Long Short-Term Memory with Conditional Random Fields

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Tsinghua Science and Technology 2021年第3期26卷 259-265页

作者： Pingchuan Ma Bo Jiang zhigang lu Ning Li Zhengwei Jiang School of Cyber Security University of Chinese Academy of SciencesBeijing 100049China Institute of Information Engineering Chinese Academy of SciencesBeijing 100093China

Network texts have become important carriers of cybersecurity information on the *** texts include the latest security events such as vulnerability exploitations,attack discoveries,advanced persistent threats,and so *** cybersecurity entities from these unstructured texts is a critical and fundamental task in many cybersecurity ***,most Named Entity Recognition(NER)models are suitable only for general fields,and there has been little research focusing on cybersecurity entity extraction in the security *** this end,in this paper,we propose a novel cybersecurity entity identification model based on Bidirectional Long Short-Term Memory with Conditional Random Fields(Bi-LSTM with CRF)to extract security-related concepts and entities from unstructured *** model,which we have named XBi LSTM-CRF,consists of a word-embedding layer,a bidirectional LSTM layer,and a CRF layer,and concatenates X input with bidirectional LSTM *** extensive experiments on an open-source dataset containing an office security bulletin,security blogs,and the Common Vulnerabilities and Exposures list,we demonstrate that XBi LSTM-CRF achieves better cybersecurity entity extraction than state-of-the-art models.

关键词： security blogs Long Short-Term Memory(LSTM) Named Entity Recognition(NER)

Influence of Sintering Temperature on Microstructure and Mechanical Properties of Al2O3 Ceramic via 3D Stereolithography

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Acta Metallurgica Sinica(English Letters) 2020年第2期33卷 204-214页

作者： He Li Yongsheng Liu Yansong Liu Kehui Hu zhigang lu Jingjing Liang Science and Technology on Thermostructural Composite Materials Laboratory Northwestern Polytechnical UniversityXi’an 710072China Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China State Key Laboratory of Tribology Tsinghua UniversityBeijing 100084China Institute of Metal Research Chinese Academy of SciencesShenyang 110016China

In this work,aluminum oxide(Al2O3) ceramic samples were fabricated by 3D stereolithography *** process was followed by debinding and *** addition,the effect of sintering temperature on micro structure and properties was *** strength was observed to increase with increasing sintering temperature due to fewer pores,fewer defects and stronger grain boundary bonding of samples at higher sintering *** flexure strength of 138.5 MPa was obtained when sintering temperature was 150℃.Furthermore,the shrinkage along length direction decreased with the decreasing sintering temperature until reaching minimum value of 1.02% after sintering at 1200℃.After sintering at 1280℃,flexure strength was 24.0 MPa and the shrinkage along length direction was 2.1%,which meets demands of ceramic core.

关键词： Stereolithography Aluminum oxide Sintering temperature Shrinkage 3D

FEW-NNN: A Fuzzy Entropy Weighted Natural Nearest Neighbor Method for Flow-Based Network Traffic Attack Detection

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China Communications 2020年第5期17卷 151-167页

作者： Liangchen Chen Shu Gao Baoxu Liu zhigang lu Zhengwei Jiang School of Computer Science and Technology Wuhan University of TechnologyWuhan 430063China Institute of Information Engineering Chinese Academy of SciencesBeijing 100093China School of Applied Technology China University of Labor RelationsBeijing 100048China School of Cyber Security University of Chinese Academy of SciencesBeijing 100049China

Attacks such as APT usually hide communication data in massive legitimate network traffic, and mining structurally complex and latent relationships among flow-based network traffic to detect attacks has become the focus of many initiatives. Effectively analyzing massive network security data with high dimensions for suspicious flow diagnosis is a huge challenge. In addition, the uneven distribution of network traffic does not fully reflect the differences of class sample features, resulting in the low accuracy of attack detection. To solve these problems, a novel approach called the fuzzy entropy weighted natural nearest neighbor(FEW-NNN) method is proposed to enhance the accuracy and efficiency of flowbased network traffic attack detection. First, the FEW-NNN method uses the Fisher score and deep graph feature learning algorithm to remove unimportant features and reduce the data dimension. Then, according to the proposed natural nearest neighbor searching algorithm(NNN_Searching), the density of data points, each class center and the smallest enclosing sphere radius are determined correspondingly. Finally, a fuzzy entropy weighted KNN classification method based on affinity is proposed, which mainly includes the following three steps: 1、 the feature weights of samples are calculated based on fuzzy entropy values, 2、 the fuzzy memberships of samples are determined based on affinity among samples, and 3、 K-neighbors are selected according to the class-conditional weighted Euclidean distance, the fuzzy membership value of the testing sample is calculated based on the membership of k-neighbors, and then all testing samples are classified according to the fuzzy membership value of the samples belonging to each class;that is, the attack type is determined. The method has been applied to the problem of attack detection and validated based on the famous KDD99 and CICIDS-2017 datasets. From the experimental results shown in this paper, it is observed that the FEW-NNN method

关键词： fuzzy entropy weighted KNN network attack detection fuzzy membership natural nearest neighbor network security intrusion detection system

Optimal Expansion Planning Model for Integrated Energy System Considering Integrated Demand Response and Bidirectional Energy Exchange

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CSEE Journal of Power and Energy Systems 2023年第4期9卷 1449-1459页

作者： Wenkai Dong zhigang lu Liangce He Jiangfeng Zhang Tao Ma Xiaobo Cao College of Electrical Engineering Yanshan UniversityQinhuangdao 066004China Department of Automotive Engineering Clemson UniversityGreenvilleSC 29607US State Grid Xiong'an New Area Electric Power Supply Company Xiong'an New Area 071000China

The challenges of energy shortage and environmen-tal protection motivate people to take various measures to use energy wisely,and integrated energy systems are such a measure to tackle this *** this paper,an optimal expansion planning model for an integrated energy system consisting of power grid,gas network and multiple energy hubs is proposed,where the planning objective is to minimize operational fuel cost and capital investment cost covering carbon capture equipment and energy hubs among *** demonstrate the advantage of the proposed planning model,six case studies are investigated,and 13.47%annual cost savings can be achieved compared with the baseline planning scenario,which does not consider bidirectional energy exchange and integrated demand response *** Terms-Bidirectional energy exchange,energy hubs,integrated energy system,integrated demand response.

关键词： Bidirectional energy exchange energy hubs integrated energy system integrated demand response.

New inverter topology for ground current suppression in transformerless photovoltaic system application

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Journal of Modern Power Systems and Clean Energy 2014年第2期2卷 191-194页

作者： Xiaoqiang GUO Huaibao WANG zhigang lu Baocheng WANG Yanshan University Qinhuangdao 066004China

An interesting inverter topology is proposed in this *** is similar to the typical three-phase full bridge inverter from the topology point of view,but smartly designed for the ground current reduction in single-phase photovoltaic(PV)inverter *** analysis is conducted to clarify the operation mechanism of the proposed *** evaluation is carried out to verify the effectiveness of the proposed topology for the ground current suppression.

关键词： Ground current Grid-connected inverter Photovoltaic(PV)system

Specific degradation of keratin in Xenopus laevis egg extracts undergoing apoptosis

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Chinese Science Bulletin 2000年第21期45卷 1977-1981页

作者： Shan Zhu zhigang lu Yingli Sun Zhonghe Zhai Beijing Univ Coll Life Sci Beijing 100871 Peoples R China

Cytochrome c activates apoptosis specific protease XCPP32 when being added to Xenopus laevis egg extracts, and induces apoptosis in this cell-free system. During apoptosis, cyto-skeleton proteins in egg extracts are degraded. Western blot assay indicates that 42-ku acidic keratin in egg extracts has been degraded by XCPP32. The degradation of 42-ku keratin may be crucial in apoptosis.

关键词： apoptosis keratin Xenopus laevis egg extracts cytochrome c XCPP32.

Identification of a DNase activated in Xenopus egg extracts undergoing apoptosis

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Chinese Science Bulletin 1998年第6期43卷 522-526页

作者： Shan Zhu Zhengfan Jiang Bo Zhang zhigang lu Zhonghe Zhai Peking Univ Coll Life Sci Beijing 100871 Peoples R China

A cell-free apoptosis system was established by adding dATP and cytochrome c to Xenopus laevis egg extracts S-150. Accompanied by an incubation process, an apoptosis-specific DNase was activated in egg extracts which depended on Mg 2+ and inhibited by Zn 2+. Two nucleases existing in egg extracts were revealed by in-gel nuclease assay. Further experiments showed that 27 ku nuclease which was different from other Ca 2+/Mg 2+-dependent nucleases was a possible candidate involved in apoptosis.

关键词： apoptosis DNase cell-free system Xenopus egg extracts

Effect of sintering temperature in argon atmosphere on microstructure and properties of 3D printed alumina ceramic cores

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Journal of Advanced Ceramics 2020年第2期9卷 220-231页

作者： He LI Yongsheng LIU Yansong LIU Qingfeng ZENG Kehui HU zhigang lu Jingjing LIANG Science and Technology on Thermostructural Composite Materials Laboratory Northwestern Polytechnical UniversityXi’anShaanxi 710072China NPU-SAS Joint Research Center of Advanced Ceramics Northwestern Polytechnical UniversityXi’anShaanxi 710072China Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China State Key Laboratory of Tribology Tsinghua UniversityBeijing 100084China Institute of Metal Research Chinese Academy of SciencesShenyang 110016China

Alumina ceramics with different sintering temperatures in argon atmosphere were obtained using stereolithography-based 3D *** effects of sintering temperature on microstructure and physical and mechanical properties were *** results show that the average particle size,shrinkage,bulk density,crystallite size,flexural strength,Vickers hardness,and nanoindentation hardness increased with the increase in sintering temperature,whereas the open porosity decreased with increasing sintering *** change was observed in phase composition,chemical bond,atomic ratio,and surface *** the sintered samples,the shrinkage in Z direction is much greater than that in X or Y *** optimum sintering temperature in argon atmosphere is 1350℃with a shrinkage of 3.0%,3.2%,and 5.5%in X,Y,and Z directions,respectively,flexural strength of 26.7 MPa,Vickers hardness of 198.5 HV,nanoindentation hardness of 33.1 GPa,bulk density of 2.5 g/cm^3,and open porosity of 33.8%.The optimum sintering temperature was 70℃higher than that sintering in air atmosphere when achieved the similar properties.

关键词： sintering temperature argon atmosphere alumina ceramics microstructure stereolithography

Blockchain abnormal behavior awareness methods: a survey

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Cybersecurity 2022年第2期5卷 92-118页

作者： Chuyi Yan Chen Zhang zhigang lu Zehui Wang Yuling Liu Baoxu Liu Institute of Information Engineering Chinese Academy of SciencesBeijing100093China School of Cyber Security University of Chinese Academy of SciencesBeijing100049China

With the wide application and development of blockchain technology in various fields such as finance, government affairs and medical care, security incidents occur frequently on it, which brings great threats to users’ assets and information. Many researchers have worked on blockchain abnormal behavior awareness in respond to these threats. We summarize respectively the existing public blockchain and consortium blockchain abnormal behavior awareness methods and ideas in detail as the difference between the two types of blockchain. At the same time, we summarize and analyze the existing data sets related to mainstream blockchain security, and finally discuss possible future research directions. Therefore, this work can provide a reference for blockchain security awareness research.

关键词： Blockchain Abnormal behavior Awareness Supervision Security detection