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面向可视分析的比特币交易地址去重算法研究

天津理工大学学报 2024年第2期40卷 84-91页

作者：刘志磊王劲松赵泽宁天津理工大学计算机科学与工程学院天津300384 智能计算及软件新技术天津市重点实验室天津300384 计算机病毒防治技术国家工程实验室天津300457

比特币是一种基于区块链的加密货币,其因具备匿名性而常被用于异常交易活动中,使得交易者的行为不容易被分析出来。因此,通过有针对性的数据可视化方法对数据进行呈现,以便于对某些实体的活动保持更加全面的了解仍然是一项挑战。作者提... 详细信息

比特币是一种基于区块链的加密货币,其因具备匿名性而常被用于异常交易活动中,使得交易者的行为不容易被分析出来。因此,通过有针对性的数据可视化方法对数据进行呈现,以便于对某些实体的活动保持更加全面的了解仍然是一项挑战。作者提出了一种比特币地址去重算法,解决了比特币交易过程中出现的地址复用现象所产生的环状数据结构问题。该方法按照时序性计算了交易发起方和接收方地址节点的出现次数并记录节点状态,每当发现重复使用的地址便会更新当前地址节点状态,并用此最新状态进行覆盖,从而保证处理后的交易数据中不存在地址重复使用的问题,降低了数据可视化的难度。然后使用桑基图这一数据可视化方法结合处理后的数据有效地展示了一些交易行为并对其进行分析。实验证明了文中方法的可行性和准确性。

关键词：公有链比特币交易数据可视化数据分析

亭子口灌区一期工程小断面软岩隧洞施工工法研究

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水利水电工程设计 2024年第1期43卷 69-71页

作者：李杰吴甲一刘志磊陈敬涛中水北方勘测设计研究有限责任公司天津300222

灌区输水隧洞多以距离长、断面小为特点,受限于较小的隧洞断面尺寸,大型成套施工机械难以发挥作用,钻爆法及悬臂掘进机组合施工方案得到了越来越多的应用。小断面长隧洞施工工法与施工支洞布置结合研究对长距离输水隧洞工程施工具有经... 详细信息

灌区输水隧洞多以距离长、断面小为特点,受限于较小的隧洞断面尺寸,大型成套施工机械难以发挥作用,钻爆法及悬臂掘进机组合施工方案得到了越来越多的应用。小断面长隧洞施工工法与施工支洞布置结合研究对长距离输水隧洞工程施工具有经济、可行等多方面的意义。以亭子口灌区一期工程第Ⅳ标段输水隧洞为研究对象,对施工方案及支洞布置进行了总结和分析,以期为类似工程设计提供借鉴意义。

关键词：小断面软岩隧洞施工工法施工工效

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基于强化学习的自适应网络威胁缓解

通信与信息技术 2024年第3期 6-10,33页

作者：齐分岭刘智磊张永军许延峰石成豪中国人民解放军66389部队山西太原030031 航天工程大学研究生院北京101400

随着互联网信息技术的深入发展,通信网络受到攻击入侵威胁也在不断变化,提出一种强化学习算法用于网络自适应威胁缓解,在SDN框架的基础上,研究使用强化学习算法用于网络安全管理。以D3QN算法为基础并对其结构进行了改进,使用改进后的D3Q... 详细信息

随着互联网信息技术的深入发展,通信网络受到攻击入侵威胁也在不断变化,提出一种强化学习算法用于网络自适应威胁缓解,在SDN框架的基础上,研究使用强化学习算法用于网络安全管理。以D3QN算法为基础并对其结构进行了改进,使用改进后的D3QN深度强化学习方法来学习缓解APT攻击,实现网络威胁自适应控制。最后对实验结果进行了评估并给出了改进算法模型的收敛结果,验证了该强化学习方法用于自适应网络威胁缓解的可用性和有效性。

关键词：强化学习 SDN 改进D3QN算法自适应网络威胁缓解

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Spatially explicit reconstruction of cropland cover in Europe from AD 1800 to 2000

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Science China Earth Sciences 2024年第9期67卷 2953-2971页

作者： Jun LI Yu YE Xiuqi FANG Diyang ZHANG zhilei WU Faculty of Geographical Science Beijing Normal UniversityBeijing 100875China Key Laboratory of Environmental Change and Natural Disaster Ministry of EducationBeijing Normal UniversityBeijing 100875China College of Geographical Science Qinghai Normal UniversityXining 810016China

One of the challenges in global change research is the significant uncertainty in global historical land use and land cover(LUCC)datasets,which are widely used as foundational *** addition to the regional cropland area reconstructions,improving the grid allocation method is another feasible way to raise the reliability of historical LUCC *** this study,an integrated reconstruction of the national cropland areas over the past 200 years was developed for 36 European *** that,the allocation algorithm was built using physiogeographic variables and historical city sites for accounting for land suitability and cultivation preferences,***,cropland data in Europe with a spatial resolution of 5′×5′at five time sections from AD 1800 to 2000 were generated using the optimal allocation algorithm in accordance with the stages of the regional *** results were as follows:(1)The dominant factors governing the distribution of croplands in Europe vary at different agricultural stages,but the results can be merged *** suitability was more optimal for allocation during the modern agricultural stage(AD 1950 and 2000);the priority index combined with land suitability and cultivation preference was more reasonable for allocation during the traditional agricultural stage(AD 1800).The average of the allocations by priority index and the land suitability could be adopted as the allocation results during the transitional stage(AD 1850 and 1900)because the grids for absolute differences within±10 and±20 percentage points between the results obtained from the above two allocations were above 80% and 95%,respectively,which means the two allocation results could be merged.(2)Over the past 200 years,the total cropland area in Europe first increased to a peak in AD 1900 and then ***,the centre of the higher cropland fraction shifted from the western part of Europe in AD 1800 to the eastern part of the continent after AD 1950.(3)

关键词： Land use and land cover change Historical cropland Gridding allocation Europe Past 200 years

On the inviscid limit of the compressible Navier-Stokes equations near Onsager's regularity in bounded domains

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Science China Mathematics 2024年第1期67卷 1-22页

作者： Robin Ming Chen zhilei Liang Dehua Wang Runzhang Xu Department of Mathematics University of PittsburghPittsburghPA 15260USA School of Mathematics Southwestern University of Finance and EconomicsChengdu 611130China College of Mathematical Sciences Harbin Engineering UniversityHarbin 150001China

The viscous dissipation limit of weak solutions is considered for the Navier-Stokes equations of compressible isentropic flows confined in a bounded *** establish a Kato-type criterion for the validity of the inviscid limit for the weak solutions of the Navier-Stokes equations in a function space with the regularity index close to Onsager’s critical *** particular,we prove that under such a regularity assumption,if the viscous energy dissipation rate vanishes in a boundary layer of thickness in the order of the viscosity,then the weak solutions of the Navier-Stokes equations converge to a weak admissible solution of the Euler *** approach is based on the commutator estimates and a subtle foliation technique near the boundary of the domain.

关键词： inviscid limit Navier-Stokes equations Euler equations weak solutions bounded domain Katotype criterion Onsager’s regularity

Surface crack evolution patterns in freeze-thaw damage of fissured rock bodies

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Journal of Mountain Science 2024年第9期21卷 3094-3107页

作者： KANG Zhiqiang WANG zhilei SHAO Luhang FENG Jiangjiang YAO Xulong College of Mining Engineering North China University of Science and TechnologyTangshan 063200China Green Intelligent Mining Technology Innovation Center of Hebei Province North China University of Science and TechnologyTangshan 063210China Luannan Macheng Mining Co. Ltd.Shougang Group Co.LtdLuannan CountyTangshan 063500China

To explore the effects of freeze‒thaw cycles on the mechanical properties and crack evolution of fissured sandstone,biaxial compression experiments were carried out on sandstone subjected to freeze‒thaw cycles to characterize the changes in the physical and mechanical properties of fissured sandstone caused by freeze‒thaw *** crack evolution and crack change process on the surface of the fissured sandstone were recorded and analysed in detail via digital image technology(DIC).Numerical simulation was used to reveal the expansion process and damage mode of fine-scale cracks under the action of freeze‒thaw cycles,and the simulation results were compared and analysed with the experimental data to verify the reliability of the numerical *** results show that the mass loss,porosity,peak stress and elastic modulus all increase with increasing number of freeze‒thaw *** an increase in the number of freeze‒thaw cycles,a substantial change in displacement occurs around the prefabricated cracks,and a stress concentration appears at the crack *** new cracks continue to sprout at the tips of the prefabricated cracks until the microcracks gradually penetrate into the main cracks,the displacement cloud becomes obviously discontinuous,and the contours of the displacement field in the crack fracture damage area simply intersect with the prefabricated cracks to form an obvious *** damage patterns of the fractured sandstone after freeze‒thaw cycles clearly differ,forming a symmetrical"L"-shaped damage pattern at zero freeze‒thaw cycles,a symmetrical"V"-shaped damage pattern at 10 freeze‒thaw cycles,and a"V"-shaped damage pattern at 20 freeze‒thaw *** 20 freeze‒thaw cycles,a"V"-shaped destruction pattern and"L"-shaped destruction pattern are formed;after 30 freeze‒thaw cycles,an"N"-shaped destruction pattern is *** shows that the failure mode of fractured sandstone gradually becomes more complicated with an increasing number of freeze‒t

关键词： Freeze‒thaw cycles Fissured sandstone Particle flow software Rock mechanics Crack extension pattern DIC technique

膝关节镜辅助下内侧髌股韧带重建与开放性内侧支持带紧缩治疗青少年复发性髌骨脱位疗效及并发症分析

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西部医学 2024年第8期36卷 1170-1174页

作者：刘志磊王薪华陈明新张力杨明明唐丽成康赵炜孙根发安康市中心医院骨科陕西安康725000 安康市中心医院康复科陕西安康725000

目的观察膝关节镜辅助下内侧髌股韧带(MPFL)重建与开放性内侧支持带紧缩治疗青少年复发性髌骨脱位疗效及分析并发症。方法回顾性分析2020年9月—2022年1月我院收治的复发性髌骨脱位的58例患者。根据治疗方式分为支持带紧缩组(n=31)和韧... 详细信息

目的观察膝关节镜辅助下内侧髌股韧带(MPFL)重建与开放性内侧支持带紧缩治疗青少年复发性髌骨脱位疗效及分析并发症。方法回顾性分析2020年9月—2022年1月我院收治的复发性髌骨脱位的58例患者。根据治疗方式分为支持带紧缩组(n=31)和韧带重建组(n=27),支持带紧缩组行开放性内侧支持带紧缩术,韧带重建组行膝关节镜辅助下MPFL重建术。分析比较两组患者髌骨恐惧试验、影像学检查结果[髌骨移动度及髌骨外侧角、髌骨适合角、髌骨倾斜角]、疼痛情况[视觉疼痛评分(VAS)]及膝关节功能评分[Lysholm膝关节功能评分量表评分(LKSS)]、[Kujala髌股关节功能评分(KPS)]及并发症。结果治疗后,两组髌骨移动度及髌骨外侧角、髌骨适合角、髌骨倾斜角均有所降低,且韧带重建组均小于支持带紧缩组(P0.05);治疗后3 d,两组VAS评分均有所升高,但韧带重建组低于支持带紧缩组(P<0.05);治疗后,两组LKSS评分和KPS评分均有所增加,且韧带重建组评分均高于支持带紧缩组(P<0.05);治疗后,韧带重建组并发症发生率7.41%低于支持带紧缩组29.03%(P<0.05)。结论膝关节镜辅助下内侧MPFL韧带重建治疗青少年复发性髌骨脱位具有良好的治疗效果,能够促进膝关节功能恢复,降低术后疼痛度,减少并发症发生率。

关键词：复发性髌骨脱位内侧髌股韧带重建内侧支持带紧缩术青少年膝关节镜辅助

A SDUDY OF NEUROPHYSIOLOGICALLY COMPUTATIONAL MODEL FOR SPEECH PRODUCTION

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A SDUDY OF NEUROPHYSIOLOGICALLY COMPUTATIONAL MODEL FOR SPEE...

具有温敏特性的光学活性嵌段聚合物Click合成与表征

第十三届全国人机语音通讯学术会议(NCMMSC2015)

作者： Bogu Li zhilei liu Jianwu Dang Bernd Kr?ger Tianjin Key Lab.of Cognitive Computing and Application Department of Phoniatrics Pedaudiology and Communication Disorders Medical School RWTH Aachen University

In this paper, we propose a neurophysiologically computational model with a physio-logical articulatory model to simulate the entire neurophysiological process of speech production. Firstly, a set of speech data for vowels and consonant-vowel(CV) syllables was generated using the physiological articulatory model driven by muscle activations;and then, the generated dataset was used as training data to learn four self-organizing maps(SOMs):speech planning, motor control, auditory feedback, and somatosensory feedback. Experimental results demonstrate that the implementation of the physiological articulatory model in the neurophysiologically computational model faithfully reflects the neurophysiological process of human speech production. The multi-connection of neurons is well verified through the "One-to-many" projection between the SOMs. The distribution of tongue and jaw in the well learned motor control map is comparable with which observed in the electrocortigraphic(ECo G) studies.

关键词： neurophysiologically computational model speech production physiological articulatory model self-organizing map

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高分子学报 2010年第6期20卷 705-713页

作者：刘志雷孙建平胡继文中国科学院广州化学研究所广州510650 中国科学院研究生院北京100039

以末端含有炔基的2-十二烷基三硫代碳酸酯-2-甲基-丙酸丙炔醇酯(DMPE)为链转移剂(CTA),2,2′偶氮二异丁腈(AIBN)为引发剂,在N,N-二甲基甲酰胺(DMF)中,利用可逆加成-断裂链转移(RAFT)聚合反应制备了分子链末端带炔基的均聚物聚(N-丙烯酰... 详细信息

以末端含有炔基的2-十二烷基三硫代碳酸酯-2-甲基-丙酸丙炔醇酯(DMPE)为链转移剂(CTA),2,2′偶氮二异丁腈(AIBN)为引发剂,在N,N-二甲基甲酰胺(DMF)中,利用可逆加成-断裂链转移(RAFT)聚合反应制备了分子链末端带炔基的均聚物聚(N-丙烯酰基-L-缬氨酰甲胺)(PAVMA—C帒CH),然后与叠氮基封端的聚乙二醇单甲醚(MPEG-N3)进行"click"偶合反应,制备具有温敏特性的光学活性嵌段聚合物MPEG-b-PAVMA.利用1H-NMR和体积排阻色谱(SEC)等表征了所合成的均聚物和共聚物的结构和分子量分布.1H-NMR结果表明所合成的嵌段共聚物中MPEG和PAVMA链段的重复单元数分别为115和55.利用紫外分光光度计测试了均聚物及嵌段聚合物的温敏特性,结果表明均聚物和共聚物在水中的低临界溶解温度(LCST)分别为6.5℃和19.5℃.比旋光度测试结果表明,均聚物和共聚物具有旋光性,同时相比于单体,其旋光能力有所降低.圆二色谱法(CD)的测试结果显示,均聚物和嵌段共聚物在220nm和197nm附近分别有一个较弱的正Cotton效应峰和一个较强的负Cotton效应峰,并且在水溶液中主要以无规的二级构象结构存在。

关键词：可逆加成-断裂链转移聚合(RAFT) “click”化学低临界溶解温度(LCST) 光学活性聚合物