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微内核操作系统互斥量模块功能正确性的形式化验证

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软件学报 2024年第9期35卷 4179-4192页

作者：张林雁李希萌施智平关永曹钦翔张倩颖首都师范大学信息工程学院北京100048 电子系统可靠性技术北京市重点实验室(首都师范大学) 北京100048 北京成像理论与技术高精尖创新中心(首都师范大学) 北京100048 上海交通大学约翰霍普克罗夫特计算机科学中心上海200030

操作系统在许多安全攸关领域为软件系统提供关键性底层支撑,操作系统中一个微小的错误或漏洞都可能引起整个软件系统的重大故障,造成巨大经济损失或危及人身安全.为了减少此类安全事故的发生,对操作系统正确性进行验证十分必要.传统测... 详细信息

操作系统在许多安全攸关领域为软件系统提供关键性底层支撑,操作系统中一个微小的错误或漏洞都可能引起整个软件系统的重大故障,造成巨大经济损失或危及人身安全.为了减少此类安全事故的发生,对操作系统正确性进行验证十分必要.传统测试手段无法穷尽系统中的所有潜在错误,因而操作系统验证有必要使用具有严格数学理论基础的形式化方法.在操作系统中,互斥量可协调多任务对资源的访问,是一种常用的任务同步方式,其功能正确性对于保障多任务应用的正确性十分关键.基于定理证明方法,在交互式定理证明器Coq中对某抢占式微内核操作系统的互斥量模块进行代码级形式化建模,给出其接口函数的形式化规范,并实现这些接口函数的功能正确性验证.

关键词：互斥量功能正确性形式化验证定理证明 Coq定理证明器

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步进索引模型下的语义及其形式化

软件学报 2022年第6期33卷 2127-2149页

作者：郭昊曹钦翔上海交通大学电子信息与电气工程学院上海200240

霍尔逻辑作为计算机程序的逻辑基础,可以用于描述一般程序的验证.分离逻辑作为霍尔逻辑的扩展,可以支持很多现代程序语言中的高阶特性.步进索引模型被用于定义自递归谓词.步进索引逻辑被广泛应用于各种基于交互式定理证明器的程序验证... 详细信息

霍尔逻辑作为计算机程序的逻辑基础,可以用于描述一般程序的验证.分离逻辑作为霍尔逻辑的扩展,可以支持很多现代程序语言中的高阶特性.步进索引模型被用于定义自递归谓词.步进索引逻辑被广泛应用于各种基于交互式定理证明器的程序验证工具中,然而,基于步进索引逻辑的推理却比经典逻辑复杂、繁琐.事实上,也可以在步进索引模型上定义更加简洁清晰的、与“步数”无关的经典逻辑体系下的非步进索引程序语义.人们希望找到步进索引逻辑和非步进索引逻辑之间的关系,但发现两种逻辑并不等价.对实际的程序验证工作中涉及的命题进行归纳总结,找出它们共同的特征,给出关于程序状态的断言的约束条件;分别定义步进索引逻辑和非步进索引逻辑体系中断言的语义,并证明在该约束条件下两种语义的等价性;在Coq中,形式化以上所有定义和证明;最后,对未来值得关注的研究方向进行初步探讨.

关键词：程序状态模型程序语言的语义形式化验证

Reynolds-number scaling analysis on lift generation of a flapping and passive rotating wing with an inhomogeneous mass distribution

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Chinese Journal of Aeronautics 2024年第2期37卷 259-269页

作者： Suyang qin Haotian HANG Yang xiang Hong LIU J.C.Wu center for aerodynamics school of aeronautics and astronauticsshanghai jiao tong universityshanghai 200240china

Insects usually fly by passively rotating wings,which has been applied to the design of flapping-wing Micro-Air Vehicles(MAVs)to reduce mechanical *** this paper,a robotic passive rotating-wing model is designed to investigate wing kinematics and lift generation,which are measured by a high-speed camera and a force transducer,*** addition,flow fields are measured using the Particle Image Velocimetry(PIV).Experimental results demonstrate that passive rotating motion has a coordinative relationship with actively stroking *** the stroke amplitude or frequency increases,the rotating amplitude is *** characterize the active stroking motion,a driving Reynolds number Redrivingis defined,which varies from 68 to 366 in this *** the gravity center of the wing towards trailing ed ge induces the increase of additional torque M,which decreases the wing rotating amplitude and promotes the advance of wing *** find that the timing of wing rotation is gradually delayed and the mean lift coefficient C^(-)_(L)monotonously decreases as *** increasing the additional torque M,C^(-)_(L)is slightly improved and approaches to the lift coefficient of a real fruit fly at driving Re approximately equal to *** instantaneous lifts combined with the vortical structures further demonstrate that the lift generation associated with wing rotation is mainly attributed to the growth of the LeadingEdge Vortex(LEV)and the passive wake capture *** wake capture is influenced by LEV,reversal stroke motion and wing additional torque together,which can only maintain the lift at a high level for a considerable *** high-lift generation mechanisms of flapping and passive rotating flight could shed light on the simplified design of MAVs and the improvement of their aerodynamic performance.

关键词： Flapping flight Unsteady lift Passive rotation Vortex flow Leading-edge vortex

Intensified warming suppressed the snowmelt in the Tibetan Plateau

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Advances in Climate Change Research 2024年第3期15卷 452-463页

作者： xiang LI Peng CUI Xue-qin ZHANG Fang ZHANG Key Lab of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China China‒Pakistan Joint Research Center on Earth Sciences Chinese Academy of Sciences and Higher Education CommissionIslamabad 45320Pakistan

Understanding how hydrological factors interrelate is crucial when examining the impact of climate warming on ***,these connections are often overlooked,leading to an unclear relationship between temperature and *** study investigates the complex interplay between temperature and snowmelt in the Tibetan Plateau from 1961 to 2020,focusing on how extreme high-temperature events affect the frequency of extreme *** a structural equation model,we detected three temperature-related factors that predominantly influenced snowmelt and extreme *** annual average temperature was found to have a significant indirect impact on snowmelt,mediated by changes in snowfall,snow depth and snow *** contrast,high-temperature days(daily maximum temperatures exceeding the 90th percentile)and heat waves(at least three consecutive high-temperature days)negatively affected extreme snowmelt directly or *** direct effect of increasing extreme temperature events was associated with an earlier onset of high-temperature periods,which accelerated snowmelt and shortened the duration of extreme snowmelt ***,the reduction in snow cover owing to warming emerged as a main factor suppressing snowmelt and extreme snowmelt *** also revealed spatiotemporal variations in the temperature‒snowmelt relationship that highly depended on changes in snowmelt *** study elucidated why warming suppresses snowmelt and extreme snowmelt events in the Tibetan Plateau,highlighting the mediating roles of snow-related and phenological *** findings will provide scientific support for climate simulation and water management policymaking in alpine regions worldwide.

关键词： Climate change Extreme temperature Snowmelt Structural equation model Tibetan Plateau

ResNeSt-biGRU: An Intrusion Detection Model Based on Internet of Things

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Computers, Materials & Continua 2024年第4期79卷 1005-1023页

作者： Yan xiang Daofeng Li Xinyi Meng Chengfeng Dong Guanglin qin School of Computer and Electronics Information Guangxi UniversityNanning530004China Guangxi Colleges and Universities Key Laboratory of Multimedia Communications and Information Processing Guangxi UniversityNanning530004China

The rapid expansion of Internet of Things (IoT) devices across various sectors is driven by steadily increasingdemands for interconnected and smart technologies. Nevertheless, the surge in the number of IoT device hascaught the attention of cyber hackers, as it provides them with expanded avenues to access valuable data. Thishas resulted in a myriad of security challenges, including information leakage, malware propagation, and financialloss, among others. Consequently, developing an intrusion detection system to identify both active and potentialintrusion traffic in IoT networks is of paramount importance. In this paper, we propose ResNeSt-biGRU, a practicalintrusion detection model that combines the strengths of ResNeSt, a variant of Residual Neural Network, andbidirectionalGated RecurrentUnitNetwork (biGRU).Our ResNeSt-biGRUframework diverges fromconventionalintrusion detection systems (IDS) by employing this dual-layeredmechanism that exploits the temporal continuityand spatial feature within network data streams, a methodological innovation that enhances detection *** conjunction with this, we introduce the PreIoT dataset, a compilation of prevalent IoT network behaviors, totrain and evaluate IDSmodels with a focus on identifying potential intrusion traffics. The effectiveness of proposedscheme is demonstrated through testing, wherein it achieved an average accuracy of 99.90% on theN-BaIoT datasetas well as on the PreIoT dataset and 94.45% on UNSW-NB15 dataset. The outcomes of this research reveal thepotential of ResNeSt-biGRU to bolster security measures, diminish intrusion-related vulnerabilities, and preservethe overall security of IoT ecosystems.

关键词： Internet of Things cyberattack intrusion detection internet security

Impedance Model for Instability Analysis of LCC-HVDCs Considering Transformer Saturation

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Journal of Modern Power Systems and Clean Energy 2024年第4期12卷 1309-1319页

作者： qin Jiang Ruiting Xu Baohong Li xiang Chen Yue Yin Tianqi Liu Frede Blaabjerg College of Electrical Engineering Sichuan UniversityChengdu 610065China Smart Grid Key Laboratory of Sichuan Province Chengdu 610065China Department of Energy Technology Aalborg UniversityAalborg 9920Denmark

In line commutated converter based high-voltage direct current(LCC-HVDC)transmission systems,the trans-former saturation can induce harmonic instability,which poses a serious threat to the safe operation of the power ***-ever,the nonlinear characteristics of the power grids introduced by the transformer saturation considerably limit the application of the conventional analysis *** address the issue,this paper derives a linear model for the transformer saturation caused by the DC current due to the converter ***-terwards,the nonlinear characteristics of power grids with the transformer saturation is described by a complex valued imped-ance *** on the derived impedance matrix,the sys-tem harmonic stability is analyzed and the mechanism of the transformer saturation induced harmonic instability is ***,the sensitivity analysis is conducted to find the key fac-tors that influence the system core saturation *** proposed impedance model is verified by the electromagnetic transient simulation,and the simulation results corroborate the effectiveness of the proposed impedance *** TermsLine commutated converter based high voltage direct current(LCC-HVDC),transformer saturation,harmonic instability,impedance model.

关键词： Line commutated converter based high voltage direct current(LCC-HVDC) transformer saturation harmonic instability impedance model

Linear shallow neural network to accelerate transmitter dispersion eye closure quaternary(TDECQ) assessment

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Science China(Information Sciences) 2024年第4期67卷 337-338页

作者： Junjiang xiang Zejun CHEN Yijun CHENG Hailin YANG Xuancheng HUO Meng xiang Gai ZHOU Yuwen qin Songnian FU Institute of Advanced Photonics Technology School of Information EngineeringGuangdong University of Technology School of Optical and Electronic Information Huazhong University of Science and Technology Key Laboratory of Photonic Technology for Integrated Sensing and Communication Ministry of Education of ChinaGuangdong University of Technology Guangdong Provincial Key Laboratory of Information Photonics Technology Guangdong University of Technology

To support the ever-emerging capacity requirement of datacenter interconnection(DCI) applications, transmitter dispersion eye closure quaternary(TDECQ) has been proposed by IEEE802.3 standard [1], which is specifically employed for the four-level pulse amplitude modulation(PAM-4) signals. However, the traditional scheme of TDECQ assessment needs several iterative operations,

关键词： IEEE Standards

Deep genome skimming reveals the hybrid origin of Pseudosasa gracilis (Poaceae: Bambusoideae)

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Plant Diversity 2024年第3期46卷 344-352页

作者： xiang-Zhou Hu Cen Guo Sheng-Yuan qin De-Zhu Li Zhen-Hua Guo Germplasm Bank of Wild Species Kunming Institute of BotanyChinese Academy of SciencesKunmingYunnan 650201China University of Chinese Academy of Sciences Beijing 100049China

Pseudosasa gracilis(Poaceae:Bambusoideae)is a temperate woody bamboo species endemic to Southcentral China with a narrow *** phylogenetic studies revealed an unexpected,isolated phylogenetic position of *** we conducted phylogenomic analysis by sampling populations of *** and its sympatric species *** and Sinosasa polytricha reflecting different genomic signals,by deep genome *** molecular evidence from chloroplast genes and genome-wide SNPs,we deciphered the phylogenetic relationships of *** plastid and nuclear data indicate that *** is more closely related to Sinosasa,which is discordant with the taxonomic *** further explore this molecular-morphological conflict,we screened 411“perfect-copy”syntenic genes to reconstruct phylogenies using both the concatenation and coalescent *** observed extensive discordance between gene trees and the putative species tree.A significant hybridization event was detected based on 411 genes from the D subgenome,showing *** was a hybrid descendant between Sinosasa longiligulata and ***,with 63.56%and 36.44%inheritance probabilities of each ***,introgression events were detected in the C subgenome between *** and *** in the same distribution *** findings suggest that sympatric hybridization and introgression play a crucial role in the origin of *** providing an empirical example of bamboo of hybrid origin using comprehensive analyses based on genomic data from different inheritance systems and morphological characters,our study represents a step forward in understanding of reticulate evolution of bamboos.

关键词： Phylogenomics Hybridization Introgression Pseudosasa gracilis Pseudosasa Sinosasa

Spatial-and spin-resolution ARPES and magnetism beamline at SSRF

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Nuclear Science and Techniques 2024年第8期35卷 23-37页

作者： Fang‑Yuan Zhu Jie‑Feng cao xiang‑Yu Meng Jun‑qin Li Rui Yu Ya‑Mei Wang Shan Qiao Bo Zhao Ming‑Zhu Zhang Zhong‑Kai Liu Mei‑Xiao Wang Yong Wang Ren‑Zhong Tai Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China ShanghaiTech Laboratory for Topological Physics School of Physical Science and TechnologyShanghai Tech UniversityShanghai 201210China University of Chinese Academy of Sciences Beijing 100049China

The BL07U beamline is a new extreme ultraviolet and soft X-ray beamline housed in the Shanghai Synchrotron Radiation Facility. Beamlines are used in nano-resolved angle-resolved photoemission spectroscopy(nano-ARPES), spin-resolved angle-resolved photoemission spectroscopy(spin-ARPES), X-ray magnetic circular dichroism spectroscopy, and X-ray magnetic linear dichroism spectroscopy for certain scientific research. The BL07U beamline, which is based on a pair of elliptical polarized undulators and a variable-included-angle plane-grating monochromator, delivers circularly or linear polarized X-rays within the energy range of 50–2000 eV. The beamline features two branches: One dedicated to nano-ARPES,which has a minimum spot size of only ~ 200 nm, and another branch comprising spin-ARPES, a vector magnetic field, and superconductive magnetic end-station.

关键词： Soft X-ray beamline Nano-ARPES Spin-ARPES XMCD/XMLD