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一种基于威胁模型的安全测试用例生成框架和工具

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软件学报 2024年第10期35卷 4573-4603页

作者：付昌兰张贺李凤龙匡宏宇南京大学软件学院江苏南京210023 计算机软件新技术国家重点实验室(南京大学) 江苏南京210023 华为云计算技术有限公司浙江杭州310053

近年来,软件系统安全问题正引发越来越多的关注,系统存在的安全威胁容易被攻击者所利用,攻击者通常采用各种攻击技术诸如口令暴力破解、网络钓鱼、SQL注入等对系统进行攻击.威胁建模是一种结构化分析、识别并处理威胁的方法,传统的测试... 详细信息

近年来,软件系统安全问题正引发越来越多的关注,系统存在的安全威胁容易被攻击者所利用,攻击者通常采用各种攻击技术诸如口令暴力破解、网络钓鱼、SQL注入等对系统进行攻击.威胁建模是一种结构化分析、识别并处理威胁的方法,传统的测试主要集中在测试代码缺陷,处于软件开发后期,不能很好地对接前期威胁建模分析成果以构建安全的软件,业界威胁建模工具缺少进一步生成安全测试的功能.为了应对此问题,提出一种从威胁模型生成安全测试用例的框架,并设计和实现工具原型.为了便于测试,对传统的攻击树模型进行改进,对构建的模型进行规范性检查,从该模型中可以自动生成测试线索.根据攻击节点发生概率对测试线索进行评估,优先检测概率较高的威胁的测试线索.对防御节点进行评估,选择收益性较高的防御方案缓解威胁,以改进系统安全设计.通过为攻击节点设置参数可以将测试线索转换成具体的测试用例.在软件开发早期阶段以威胁建模识别出的威胁作为输入,通过框架和工具可以生成测试,指导后续的安全开发和安全测试设计,将安全技术更好地嵌入到软件设计和开发之中.案例研究部分将该框架和工具运用于极高危风险的安全测试生成,并说明了其有效性.

关键词：威胁模型威胁建模攻击树模型测试用例生成测试线索

Research on the application of digital power supply based on domestic FPGA

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Radiation Detection Technology and Methods 2023年第3期7卷 399-409页

作者： Xiao li Chao Han feng li long University of Chinese Academy of Sciences Courtyard ANo.19 Yuquan RoadBeijing 100049China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China

Purpose The digital controller for the accelerator magnet power supply typically employs a field-programmable gate array(FPGA)as the signal processing chip for executing digital processing of closed-loop ***,FPGA chips are predominantly utilized in Intel or Xilinx *** address the“key areas and stranglehold”issue pertaining to FPGA chips in accelerator power supply,we have devised a digital power supply prototype using a domestic FPGA chip and validated its feasibility in the upgrade project’s magnet power supply digital transformation plan for the Beijing Electron Positron Collider(BEPCII).Method A domestic FPGA chip from the Seal5000 SA5Z-30-D1 series by Xi’an ZhiDuoJing Microelectronics *** as the core component for the design of a digital corrector magnet power supply to replace the existing analog controlled corrector power supply at *** power supply’s digital control of the closed loop is achieved through the use of a hardware description language,and the digital controller hardware is constructed based on the original power supply power *** and conclusions After conducting experiments and tests on the power supply prototype,we have successfully met the current operational requirements of the BEPCII corrector power supply,thus confirming the feasibility of utilizing domestic FPGA for digital application on accelerator power supply.

关键词： Domestic FPGA Power supply digital controller of accelerator PID algorithm PWM

Synthesis of a New Asymmetrical Ether Diamine with Aromatic Structure and Related Polyimide

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Chinese Chemical Letters 2006年第5期17卷 635-636页

作者： Yu SHAO Yah feng li Xiao long WANG Shu Jiang ZHAN Xin ZHAO Tao MA State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical Engineering Lanzhou University Lanzhou 730000

A new aromatic asymmetrical ether diamine, 1,4-bis（3＇,4’-diaminophenoxy）benzene 3 was synthesized in three steps, using hydroquinone as starting material. A new aromatic polyimide containing asymmetrical diaryl ether segments was prepared from the resulting diamine with 4,4＇-oxydiphthalic anhydride （ODPA） via a conventional two-step thermal or chemical imidization method. The resulting polyimide exhibits high thermal resistance, excellent solubility, film-forming capability, high mechanical strength and modulus.

关键词： Polyimide asymmetrical ether diamine aromatic polyimide.

Application of GNSS-PPP on Dynamic Deformation Monitoring of Offshore Platforms

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China Ocean Engineering 2024年第2期38卷 352-361页

作者： YU li-na XIONG Kuan GAO Xi-feng li Zhi FAN li-long ZHANG Kai Institute of Ocean Energy and Intelligent Construction Tianjin University of TechnologyTianjin 300384China China Railway Construction Bridge Engineering Bureau Group Co.LTD Tianjin 300300China School of Civil Engineering Tianjin UniversityTianjin 300072China Department of Land Surveying and Geo-Informatics The Hong Kong Polytechnic UniversityHong KongChina State Key Laboratory of Precision Blasting Jianghan UniversityWuhan 430056China

The real-time dynamic deformation monitoring of offshore platforms under environmental excitation is crucial to their safe *** Global Navigation Satellite System-Precise Point Positioning(GNSS-PPP)has been considered for this purpose,its monitoring accuracy is relatively ***,the influence of background noise on the dynamic monitoring accuracy of GNSS-PPP remains ***,it is imperative to further validate the feasibility of GNSS-PPP for deformation monitoring of offshore *** address these concerns,vibration table tests with different amplitudes and frequencies are *** results demonstrate that GNSS-PPP can effectively monitor horizontal vibration displacement as low as±30 mm,which is consistent with ***,the spectral characteristic of background noise in GNSS-PPP is similar to that of GNSS-RTK(Real Time Kinematic).Building on this observation,an improved Complete Ensemble Empirical Mode Decomposition with Adaptive Noise(CEEMDAN)has been proposed to de-noise the data and enhance the dynamic monitoring accuracy of *** monitoring application research is also undertaken,successfully extracting and analyzing the dynamic deformation of an offshore platform structure under environmental excitation using GNSS-PPP monitoring in conjunction with improved CEEMDAN *** comparing the de-noised dynamic deformation trajectories of the offshore platform during different periods,it is observed that the platform exhibits reversible alternating vibration responses under environmental excitation,with more pronounced displacement deformation in the direction of load *** research results confirm the feasibility and potential of GNSS-PPP for dynamic deformation monitoring of offshore platforms.

关键词： GNSS-PPP offshore platform dynamic deformation monitoring improved CEEMDAN de-noising

Substructure Prediction from Infrared Spectra by Using Support Vector Machines

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Chinese Chemical Letters 2005年第10期16卷 1354-1356页

作者： Jun Hong liU Min Chun LU Fu Sheng NIE Xiao Yu feng Meng long li College of Chemistry Sichuan University Chengdu 610064

The potential of support vector machines （SVMs） for the substructure elucidation of infrared spectra have been investigated. The trained SVMs can identify the 16 substructures with high accuracy.

关键词： Infrared spectra substructures support vector machines.

Frequency Domain Fatigue Evaluation on SCR Girth-Weld Based on Structural Stress

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China Ocean Engineering 2024年第2期38卷 255-270页

作者： ZHANG long ZHAO Tian-feng College of Safety and Ocean Engineering China University of Petroleum(Beijing)Beijing 102249China

The Steel Catenary Riser(SCR)is a vital component for transporting oil and gas from the seabed to the floating *** harsh environmental conditions and complex platform motion make the SCR’s girth-weld prone to fatigue *** structural stress fatigue theory and Master S-N curve method provide accurate predictions for the fatigue damage on the welded joints,which demonstrate significant potential and compatibility in multi-axial and random fatigue ***,we propose a new frequency fatigue model subjected to welded joints of SCR under multiaxial stress,which fully integrates the mesh-insensitive structural stress and frequency domain random process and transforms the conventional welding fatigue technique of SCR into a spectrum analysis technique utilizing structural ***,a full-scale FE model of SCR with welds is established to obtain the modal structural stress of the girth weld and the frequency response function(FRF)of modal coordinate,and a biaxial fatigue evaluation about the girth weld of the SCR can be achieved by taking the effects of multi-load correlation and pipe-soil interaction into *** research results indicate that the frequency-domain fatigue results are aligned with the time-domain results,meeting the fatigue evaluation requirements of the SCR.

关键词： SCR girth weld random vibration self(cross)power spectrum structural stress method biaxial fatigue damage

Progress in processing of porous titanium:a review

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Rare Metals 2024年第5期43卷 1932-1955页

作者： Xiao-li Yang Xian-feng Du Zhi-lin Xu Zhong-Shuai liang li-long Xiong Engineering Research Center of Energy Storage Materials and Devices Ministry of EducationSchool of ChemistryXi'an Jiaotong UniversityXi'an 710049China

As a novel structural and functional material,porous titanium and its alloys have been widely used in the aerospace,marine engineering and biomedical fields due to their high corrosion resistance,low density,good biocompatibility and excellent mechanical ***,in this paper,a comprehensive review of powder metallurgy(PM)(including additive manufacturing(AM)processes)for fabricating porous titanium is firstly covered in terms of their working principles,capabilities,shortcomings and ***,the influencing factors of various methods on final pore structure of porous Ti are ***,a summary of the chemical methods(CM)to obtain the porous Ti is also provided,such as dealloying method and reduction ***,the tendency and direction of preparation technology as well as application of porous titanium were prospected.

关键词： Porous titanium Powder metallurgy Chemical method Pore structure Processing process

Integrating Shipborne Images with Multichannel Deep Learning for Landslide Detection

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Journal of Earth Science 2024年第1期35卷 296-300页

作者： Pengfei feng Changdong li Shuang Zhang Jie Meng Jingjing long School of Mechanical Engineering and Electronic Information China University of GeosciencesWuhan 430074China Faculty of Engineering China University of GeosciencesWuhan 430074China Department of Civil Badong National Observation and Research Station of Geohazards China University of GeosciencesWuhan 430074China College of Geology Engineering and Geomatics Changan UniversityXi'an 710054China Department of Geosciences University of OsloOslo 0316Norway

0 *** disasters in recession zones along riverbanks impose significant global social,economic,and ecological *** areas are particularly susceptible to *** inflict significant harm due to fluctuating water levels(Meng et al.,2023;Dai et al.,2021;li et al.,2021).This,in turn,endangers the safety and accessibility of roads and waterways adjacent to rivers,and hydropower station and reservoir security(Yan et al.,2022;Guo et al.,2020;Tang et al.,2017).

关键词： reservoir Landslide Ship

Phase separation of GRP7 facilitated by FERONIAmediated phosphorylation inhibits mRNA translation to modulate plant temperature resilience

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Molecular Plant 2024年第3期17卷 460-477页

作者： Fan Xu long Wang Yingbin li Junfeng Shi Dorothee Staiger feng Yu state Key Laboratory of Chemo/Biosensing and Chemometrics College of Biologyand Hunan Key Laboratory of Plant Functional Genomics and Developmental RegulationHunanUniversityChangsha 410082P.R.China State Key Laboratory of Hybrid Rice Hunan Agricultural Biotechnology Research InstituteHunan Academy of Agricultural SciencesChangsha 410125P.R.China RNA Biology and Molecular Physiology Faculty of BiologyBielefeld University33615 BielefeldGermany

Changes in ambient temperature profoundly affect plant growth and ***,the molecu-larbasis of plant acclimation to temperature fluctuation is of great *** this study,we discovered that GLYCINE-RICH RNA-BINDING PROTEIN 7(GRP7)contributes to cold and heat tolerance in Arabidopsis *** found that exposure to a warm temperature rapidly induces GRP7 condensates in planta,which can be reversed by transfer to a lower *** biology and biochemical assays revealed that GRP7 undergoes liquid-liquid phase separation(LLPS)in vivo and in *** of GRP7 in the cyto-plasm contributes to the formation of stress granules that recruit RNA,along with the translation machinery component eukaryotic initiation factor 4E1(elF4E1)and the mRNA chaperones COLD SHOCK PROTEIN 1(CSP1)and CSP3,to inhibit ***,natural variations in GRP7 affecting the residue phos-phorylated by the receptorkinase FERONIA alter its capacity to undergo LLPS and correlate with the adap-tation of some Arabidopsis accessions to a widertemperature *** together,ourfindings illustrate the role of translational control mediated by GRP7 LLPS to confer plants with temperature resilience.

关键词： fluctuating temperature glycine-rich RNA-binding protein phase separation cold shock proteins translation