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Dynamic Stability and Fuzzy Reliability Analysis of Toppling Perilous Rock Under Seismic Excitation

Journal of Earth Science 2024年第1期35卷 248-262页

作者： Linfeng Wang Jixu Zhang wanchun xia xiaoming Huang Guojin Tan Key Laboratory of Geological Hazards Mitigation for Mountainous Highway and Waterway Chongqing Jiaotong UniversityChongqing 400074China School of Transportation Southeast UniversityNanjing 211189China College of Transportation Jilin UniversityChangchun 130012China

To predict the occurrence of the collapse disaster in toppling perilous rock under the action of bidirectional earthquakes,the dynamic stability and fuzzy reliability calculation method of toppling perilous rock under the action of bidirectional earthquakes is ***,the mass viscoelasticity model is used to simulate two main control surfaces of toppling perilous rock,the seismic dynamic response model and motion equation of toppling perilous rock are established based on the D'Alembert principle,and the Newmark-β method is used to solve the dynamic motion ***,the instability event of toppling perilous rock is considered a fuzzy event,the membership function expression of the stability coefficient of toppling perilous rock is determined based on the fuzzy failure criterion,the calculation equations of the toppling perilous rock dynamic stability coefficient and fuzzy reliability are established,and the fuzzy reliability evaluation method based on the probability distribution of reliability is ***,the influence of different superposition modes of seismic excitation on the fuzzy reliability of toppling perilous rock is *** calculation results of toppling perilous rock in the engineering case show that the fuzzy reliability calculated after considering the fuzzy failure criterion is reduced by 10.73% to 25.66% compared with the classical *** the bidirectional seismic excitation,the fuzzy reliability of toppling perilous rock is reduced by 5.46% to 14.89%.Compared with using the acceleration peak time encounter mode to superpose the seismic excitation,the fuzzy reliability of toppling perilous rock is reduced by 3.4% when the maximum action effect time encounter mode is adopted.

关键词： toppling perilous rock bidirectional earthquake fuzzy failure criterion dynamic stability fuzzy reliability Newmark-βmethod probability distribution function

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Dynamic Stability and Fuzzy Reliability Analysis of Toppling Perilous Rock Under Seismic Excitation

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Journal of Earth Science 2022年

作者： Linfeng Wang Jixu Zhang wanchun xia xiaoming Huang Guojin Tan Key Laboratory of Geological Hazards Mitigation for Mountainous Highway and Waterway Chongqing Jiaotong University School of Transportation Southeast University College of Transportation Jilin University

To predict the occurrence of the collapse disaster in toppling perilous rock under the action of bidirectional earthquakes,the dynamic stability and fuzzy reliability calculation method of toppling perilous rock under the action of bidirectional earthquakes is ***,the mass viscoelasticity model is used to simulate two main control surfaces of toppling perilous rock,the seismic dynamic response model and motion equation of toppling perilous rock are established based on the D'Alembert principle,and the Newmark-βmethod is used to solve the dynamic motion ***,the instability event of toppling perilous rock is considered a fuzzy event,the membership function expression of the stability coefficient of toppling perilous rock is determined based on the fuzzy failure criterion,the calculation equations of the toppling perilous rock dynamic stability coefficient and fuzzy reliability are established,and the fuzzy reliability evaluation method based on the probability distribution of reliability is ***,the influence of different superposition modes of seismic excitation on the fuzzy reliability of toppling perilous rock is *** calculation results of toppling perilous rock in the engineering case show that the fuzzy reliability calculated after considering the fuzzy failure criterion is reduced by 10.73%to 25.66%compared with the classical *** the bidirectional seismic excitation,the fuzzy reliability of toppling perilous rock is reduced by 5.46% to 14.89%.Compared with using the acceleration peak time encounter mode to superpose the seismic excitation,the fuzzy reliability of toppling perilous rock is reduced by 3.4%when the maximum action effect time encounter mode is adopted.

关键词： toppling perilous rock bidirectional earthquake fuzzy failure criterion dynamic stabil-ity fuzzy reliability Newmark-βmethod probability distribution function

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化学及干湿循环作用下泥灰岩损伤劣化特性分析

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防灾减灾工程学报 2022年第5期42卷 976-985页

作者：王林峰程平夏万春唐宁重庆交通大学山区公路水运交通地质减灾重庆市高校市级重点实验室重庆400074 成都理工大学地质灾害防治与地质环境保护国家重点实验室四川成都610059

库岸岩质边坡底部受水的化学腐蚀及水位变化形成的干湿循环影响,其强度远低于一般岩体。泥灰岩作为一种强度较差的特殊岩体,更易受到地质、水文等因素的联合破坏。对三峡库区巫山段常见的泥灰岩进行化学溶液浸泡及干湿循环作用,开展单... 详细信息

库岸岩质边坡底部受水的化学腐蚀及水位变化形成的干湿循环影响,其强度远低于一般岩体。泥灰岩作为一种强度较差的特殊岩体,更易受到地质、水文等因素的联合破坏。对三峡库区巫山段常见的泥灰岩进行化学溶液浸泡及干湿循环作用,开展单轴压缩试验、直剪试验、电镜扫描试验、数值模拟,并采用PSO-BP神经网络对抗剪强度参数进行预测。研究结果表明:泥灰岩在化学及干湿循环作用后的受力变形经历着裂纹起裂-扩展-延伸-破坏四个阶段,破坏时的裂纹扩展路径呈现多向发展的趋势;岩石的单轴抗压强度、内摩擦角、黏聚力在酸性增强及干湿循环次数增加后都有明显下降,这主要与其内部结构、矿物组成有关,干湿循环作用下的热胀冷缩及化学作用下的腐蚀,加剧了泥灰岩内部裂隙扩展、孔隙增大;PSO-BP神经网络能较好地预测泥灰岩抗剪强度参数在不同pH值、不同干湿循环次数下的值,误差较小,可将该方法运用到类似案例分析中。

关键词：化学腐蚀干湿循环泥灰岩劣化 PSO-BP

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基于模糊失效准则的危岩稳定可靠度计算

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防灾减灾工程学报 2022年第4期42卷 695-704页

作者：张继旭王林峰夏万春重庆交通大学山区公路水运交通地质减灾重庆市高校市级重点实验室重庆400074

为预测危岩崩塌灾害的发生,分别选取影响三种不同类型危岩稳定性的主要参数作为随机变量X1~X5,基于模糊失效准则和可靠度理论建立了危岩模糊可靠度计算模型和方法。首先,根据危岩稳定系数的隶属函数表达式,引入新随机变量X6,将稳定系数... 详细信息

为预测危岩崩塌灾害的发生,分别选取影响三种不同类型危岩稳定性的主要参数作为随机变量X1~X5,基于模糊失效准则和可靠度理论建立了危岩模糊可靠度计算模型和方法。首先,根据危岩稳定系数的隶属函数表达式,引入新随机变量X6,将稳定系数的隶属函数作为新随机变量X6的概率分布函数,得到了随机变量X6的概率分布形式。然后,针对三种不同类型危岩分别建立了危岩失稳模糊事件的等效功能函数和模糊可靠度计算模型。最后,采用改进的Monte-Carlo法计算了危岩失稳模糊事件的失效概率。对万州首立山6块单体危岩进行分析,结果表明:当危岩稳定系数从小至大变化,考虑模糊失效准则后危岩的失效概率增加幅度经历由小变大再变小的过程,即处于欠稳定~基本稳定状态下的危岩模糊性较强,判断其真实稳定性状态较困难,实际工程中针对这类危岩仅采用经典可靠度计算方法得到的结果存在一定风险,需考虑模糊失效对危岩可靠度的影响。

关键词：危岩崩塌模糊失效准则可靠度理论隶属函数等效功能函数 Monte-Carlo法

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考虑库水升降和滑带弱化作用的岸坡启滑机制分析

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中国地质灾害与防治学报 2023年第2期34卷 30-41页

作者：王林峰夏万春冉楗张继旭程平重庆交通大学山区公路水运交通地质减灾重庆市高校市级重点实验室重庆400074 地质灾害防治与地质环境保护国家重点实验室(成都理工大学) 四川成都610059

以三峡库区凉水井滑坡为研究对象,采用理论分析与数值模拟的研究手段,构建了滑带强度弱化模型,提出了渗流驱动的滑坡启滑判据,应用Geo-studio有限元程序分析了库水不同升降速率对滑坡稳定性的影响,揭示了库水升降作用下岸坡渗流场演变... 详细信息

以三峡库区凉水井滑坡为研究对象,采用理论分析与数值模拟的研究手段,构建了滑带强度弱化模型,提出了渗流驱动的滑坡启滑判据,应用Geo-studio有限元程序分析了库水不同升降速率对滑坡稳定性的影响,揭示了库水升降作用下岸坡渗流场演变规律和渗流驱动下的启滑机制。研究表明:(1)渗透压力与渗透时间的变化是滑带土强度弱化的关键因素,弱化到临界强度时,在渗流驱动下发生压剪破坏而启滑,由局部向整体以渐进模式破坏失稳;(2)库水升降过程中,坡体内孔隙水压力滞后性较明显,水位升降速率会影响坡体地下水响应时程,升降速率越大,孔隙水压力变化越大,渗流驱动力越大,滑坡稳定性变化越快,越趋近于渐进破坏;(3)库水位从175 m降到145 m,凉水井滑坡滑面法向应力最大降低了38.19%,剪应力最大降低了22.20%,有效法向应力最大落差为168.64 kPa,抗剪强度最大落差为63.45 kPa。以上分析结论与规律可为涉水滑坡启滑机制分析、库岸山体滑坡失稳研究及应急防治工程等提供科学依据和理论方法。

关键词：滑坡库水升降启滑判据渗流稳定性 Geo-studio 三峡库区

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酸环境干湿循环作用下泥灰岩损伤劣化分析

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工程地质学报 2022年第6期30卷 2006-2015页

作者：夏万春王林峰张继旭冉楗杨柳钟宜宏重庆交通大学山区公路水运交通地质减灾重庆市高校市级重点实验室重庆400074

针对库区消落带泥灰岩的最不利作用环境——酸环境干湿循环下力学性质损伤劣化问题,以岸坡泥灰岩为研究对象,分别开展pH=3,5,7溶液条件下的干湿循环试验,分析了酸环境干湿循环作用下泥灰岩单轴抗压强度的劣化规律,查明了其对泥灰岩力学... 详细信息

针对库区消落带泥灰岩的最不利作用环境——酸环境干湿循环下力学性质损伤劣化问题,以岸坡泥灰岩为研究对象,分别开展pH=3,5,7溶液条件下的干湿循环试验,分析了酸环境干湿循环作用下泥灰岩单轴抗压强度的劣化规律,查明了其对泥灰岩力学性质的损伤劣化特性,采用颗粒流软件对比探究了不同循环次数对力学强度参数的影响规律,并结合库区消落带岩体劣化现象分析了层进劣化机理。研究结果表明:pH=3,5,7溶液环境下泥灰岩单轴抗压强度变化均与干湿循环次数呈反比关系,累积劣化度Sn在34.79%~54.31%之间变化,且呈现快速上升、缓慢发展、趋于平稳的变化趋势,而峰值应力劣化范围为8.79%~35.61%;泥灰岩黏聚力C、内摩擦角φ、弹性模量E均随干湿循环次数的增加而不断降低,且损伤劣化以圈层渐进的模式进行;库区消落带岩体受到酸溶液干湿循环作用后,附近岩体会萌生大量次生裂隙,随着循环次数的推进及损伤的持续累积,裂隙逐渐贯通并向坡内层进扩展,扩展范围和速率与干湿循环次数和溶液pH值有关。以上分析结论与规律可为库岸山体滑坡崩塌失稳、库区危岩基座软化、蓄水渗漏等灾害的预测与应急防治提供科学依据和理论方法。

关键词：干湿循环泥灰岩三轴压缩颗粒流损伤劣化

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XRL-SHAP-Cache:an explainable reinforcement learning approach for intelligent edge service caching in content delivery networks

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Science China(Information Sciences) 2024年第7期67卷 46-71页

作者： xiaolong XU Fan WU Muhammad BILAL xiaoyu xia wanchun DOU Lina YAO Weiyi ZHONG School of Software Nanjing University of Information Science and Technology School of Computing and Communications Lancaster University School of Computing Technologies Royal Melbourne Institute of Technology State Key Laboratory for Novel Software Technology Nanjing University School of Computer Science and Engineering University of New South Wales Data 61 Commonwealth Scientific and Industrial Research Organization School of Computer Science Qufu Normal University

Content delivery networks(CDNs) play a pivotal role in the modern internet infrastructure by enabling efficient content delivery across diverse geographical regions. As an essential component of CDNs, the edge caching scheme directly influences the user experience by determining the caching and eviction of content on edge servers. With the emergence of 5G technology, traditional caching schemes have faced challenges in adapting to increasingly complex and dynamic network environments. Consequently, deep reinforcement learning(DRL) offers a promising solution for intelligent zero-touch network governance. However, the blackbox nature of DRL models poses challenges in understanding and making trusting decisions. In this paper,we propose an explainable reinforcement learning(XRL)-based intelligent edge service caching approach,namely XRL-SHAP-Cache, which combines DRL with an explainable artificial intelligence(XAI) technique for cache management in CDNs. Instead of focusing solely on achieving performance gains, this study introduces a novel paradigm for providing interpretable caching strategies, thereby establishing a foundation for future transparent and trustworthy edge caching solutions. Specifically, a multi-level cache scheduling framework for CDNs was formulated theoretically, with the D3QN-based caching scheme serving as the targeted interpretable model. Subsequently, by integrating Deep-SHAP into our framework, the contribution of each state input feature to the agent's Q-value output was calculated, thereby providing valuable insights into the decision-making process. The proposed XRL-SHAP-Cache approach was evaluated through extensive experiments to demonstrate the behavior of the scheduling agent in the face of different environmental *** results demonstrate its strong explainability under various real-life scenarios while maintaining superior performance compared to traditional caching schemes in terms of cache hit ratio, quality of service(QoS),a

关键词： deep reinforcement learning (DRL) explainable artificial intelligence (XAI) multi-level cache content delivery network (CDN) D3QN algorithm Deep-SHAP

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SapBase:A central portal for functional and comparative genomics of Sapindaceae species

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Journal of Integrative Plant Biology 2024年第8期66卷 1561-1570页

作者： Jiawei Li Chengjie Chen Zaohai Zeng Fengqi Wu Junting Feng Bo Liu Yingxiao Mai Xinyi Chu wanchun Wei Xin Li Yanyang Liang YuanLong Liu Jing Xu Rui xia State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources College of HorticultureSouth China Agricultural UniversityGuangzhou 510640China Guangdong Laboratory for Lingnan Modern Agriculture South China Agricultural UniversityGuangzhou 510640China Key Laboratory of Biology and Germplasm Enhancement of Horticultural Crops in South China at the Ministry of Agriculture and Rural Affairs South China Agricultural UniversityCollege of HorticultureGuangzhou 510640China

The Sapindaceae family,encompassing a wide range of plant forms such as herbs,vines,shrubs,and trees,is widely distributed across tropical and subtropical *** family includes economically important crops like litchi,longan,rambutan,and *** the wide application of genomic technologies in recent years,several Sapindaceae plant genomes have been decoded,leading to an accumulation of substantial omics data in this *** surge in data highlights the pressing need for a unified genomic data center capable of storing,sharing,and analyzing these ***,we introduced SapBase,that is,the Sapindaceae Genome *** houses seven published plant genomes alongside their corresponding gene structure and functional annotations,small RNA annotations,gene expression profiles,gene pathways,and synteny block *** offers user-friendly features for gene information mining,co-expression analysis,and interspecies comparative genomic ***,we showcased SapBase's extensive capacities through a detailed bioinformatic analysis of a MYB gene in ***,Sap Base could serve as an integrative genomic resource and analysis platform for the scientific exploration of Sapinaceae species and their comparative studies with other plants.

关键词： functional crops unified

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ABRUPT CHANGE OF LAKE ENVIRONMENT IN WEST CHINA: AN EVIDENCE FOR GLOBAL CLIMATE WARMING

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地学前缘 2000年第S1期7卷 375-376页

作者： Li Shijie, Shi Yafeng, Li wanchun, Wu Jinglu, Yin Yu, Yang xiangdong,xia Weilan[WT5,5”BX](Nanjing Institute of Geography and Limnology, CAS. Nanjing 210008, China,E\|mail:shjli@***)

Expanding or shrinking of lakes, especially in the closed basin, directly reflects the balance situation of water\|heat regime in the catchment. Fluctuations of the water\|level can be used as an indicator of climatic and environmental changes. Authors have investigated many lakes in West China in recent years, including lakes in the Tibet Plateau and in the arid area in the northwest China. We found that all lakes have been in shrinkage, some of them were changed into swamp and some dried dramatically up, which caused the abrupt change of the lake environment. This change led the grassland to be retrogression and desertification, and made the eco\|environment deterioration in West *** Xingcuo Lake, in the height of 3425m ASL with 29km\+2 drainage area, located in the Zoige Basin, Northeastern Tibet Plateau, had changed into swamp in the area of 2km\+2 , and the vast area of peripheral marsh changed into grassland by the years of 1990. But the topographic map in the scale of 1/100000 and aerial photography surveyed at the end of 1960’s show clearly that this lake was in the area of 3 3km\+2 and surrounded by vast area of marshland. In the north central part of the Tibet Plateau, the Gourencuo Lake, in the height of 4650m ASL, was in the area of 23 5km\+2 with the average water depth of 1 3m in 1990. Then a dramatic change had been appearing in the recent years. When authors went there again in 1998,they found that the lake dried fully up. A thin salt crystal layer with saturated brine covered the flat central lake floor. This means that at least 30×10 6 m 3 water volume stored in the lake had been lost by the evaporation in 8 years, and many sand dunes had been formed. This abrupt change of lake environment could be recognized as the result of natural process or climate warming because of no human activity there.

关键词： abrupt change lake environment West China climate warming

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人免疫球蛋白联合阿昔洛韦治疗病毒性脑炎患儿的效果

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中国民康医学 2024年第4期36卷 104-106,126页

作者：袁霞刘婉春解放军联勤保障部队第九九〇医院儿科河南驻马店463000

目的:观察人免疫球蛋白联合阿昔洛韦治疗病毒性脑炎患儿的效果。方法:选取2020年3月至2023年3月该院收治的76例病毒性脑炎患儿进行前瞻性研究,按照随机数字表法将其分为对照组和观察组各38例。对照组给予阿昔洛韦治疗,观察组在对照组基... 详细信息

目的:观察人免疫球蛋白联合阿昔洛韦治疗病毒性脑炎患儿的效果。方法:选取2020年3月至2023年3月该院收治的76例病毒性脑炎患儿进行前瞻性研究,按照随机数字表法将其分为对照组和观察组各38例。对照组给予阿昔洛韦治疗,观察组在对照组基础上联合人免疫球蛋白治疗。比较两组临床疗效,临床症状改善时间,治疗前后炎性因子[降钙素原(PCT)、γ干扰素(INF-γ)、白细胞介素-6(IL-6)]水平、免疫功能指标[免疫球蛋白M(IgM)、免疫球蛋白G(IgG)]水平,以及不良反应发生率。结果:观察组治疗总有效率为92.11%(35/38),高于对照组的73.68%(28/38),差异有统计学意义(P0.05)。结论:人免疫球蛋白联合阿昔洛韦治疗病毒性脑炎患儿可提高临床疗效,促进临床症状恢复,减轻机体炎症反应,提高免疫功能,效果优于单纯阿昔洛韦治疗。

关键词：病毒性脑炎阿昔洛韦人免疫球蛋白不良反应炎性因子

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