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广义Orlicz序列空间的非方性 被引量:2
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作者 石忠锐 张博 《应用数学与计算数学学报》 2012年第4期376-381,共6页
研究了广义Orlicz序列空间关于Luxemburg范数的非方性,参考经典Orlicz空间的讨论方法,发展了广义情形下的新方法,给出了判别该性质的充要条件.
关键词 ORLICZ函数 广义Orlicz序列空间 方性
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L_P(E,μ)的非方性,非l_n^(1)性和K一致凸性
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作者 陈连昌 谢刚 《大庆石油学院学报》 CAS 北大核心 1992年第3期84-88,共5页
首先证明了非方性和非l_?^(1)性可以从Banach空间E提升到Lebesgue-Bochner函数空间L_ρ(E,μ),然后指出L_ρ(E,μ)是K一致凸的充分必要条件是E是一致凸的。
关键词 函数空产是 方性 非Ln^(1)性
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2002年新疆农三师地方性氟中毒调查报告 被引量:2
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作者 魏宏 白润本 +4 位作者 杨瑞英 李新梅 雷建华 哈丽旦 米亚沙尔 《地方病通报》 2005年第2期35-37,共3页
目的掌握新疆生产建设兵团农三师地方性氟中毒的病情现况,为今后地方性氟中毒的防治提供科学依据。方法在14个较大的农牧团场中心小学,采用分层整群抽样方法,调查8~12岁学生氟斑牙患病情况;检测饮水氟含量,8~12岁学生尿氟含量;调查改... 目的掌握新疆生产建设兵团农三师地方性氟中毒的病情现况,为今后地方性氟中毒的防治提供科学依据。方法在14个较大的农牧团场中心小学,采用分层整群抽样方法,调查8~12岁学生氟斑牙患病情况;检测饮水氟含量,8~12岁学生尿氟含量;调查改水情况。结果8~12岁学生氟斑牙总患病率为20.62%,维族患病率明显低于汉族,地方性氟中毒的流行主要集中在1个较小的区域(42团场)并达到轻病区水平;饮水氟浓度为1.11±1.06mg/L;8~12岁学生尿氟含量为1.45±1.02mg/L;改水率达到75%。结论生产建设兵团农三师地方性氟中毒病情在大部分地区基本得到控制,在一个较小局部区域存在轻病区水平的流行,应作为重点加大投入进行改水工作。 展开更多
关键词 方性氟中毒 轻病区 现况调查 农三师 新疆兵团
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赋Orlicz范数下Orlicz-Lorentz序列空间的一致正规结构和一致非方性
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作者 陈博文 巩万中 《应用数学》 CSCD 北大核心 2021年第2期436-447,共12页
Orlicz-Lorent空间作为经典Orlicz空间的推广,为调和分析及微分方程提供了合理的空间框架,而一致正规结构和一致非方性在不动点理论领域有着重要的应用.本文给出了赋Orlicz范数下Orlicz-Lorentz序列空间具有一致正规结构和一致非方性的... Orlicz-Lorent空间作为经典Orlicz空间的推广,为调和分析及微分方程提供了合理的空间框架,而一致正规结构和一致非方性在不动点理论领域有着重要的应用.本文给出了赋Orlicz范数下Orlicz-Lorentz序列空间具有一致正规结构和一致非方性的充要条件. 展开更多
关键词 一致正规结构 一致非方性 Orlicz-Lorentz序列空间 ORLICZ范数
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《瓦城三部曲》之“方性”人格研究
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作者 王显星 《武夷学院学报》 2015年第7期39-43,共5页
当代作家鬼子在其知名中篇集子《瓦城三部曲》中塑造了一个个个性鲜明的人物形象,这些人物形象在与现实的抗争中显示出的是一种"一根筋"式、坚持到底的人格特点,未表现出半点与现实"屈服或和解"的倾向。这种人性特... 当代作家鬼子在其知名中篇集子《瓦城三部曲》中塑造了一个个个性鲜明的人物形象,这些人物形象在与现实的抗争中显示出的是一种"一根筋"式、坚持到底的人格特点,未表现出半点与现实"屈服或和解"的倾向。这种人性特点,简言概括之,就是一种"方性"人格特点,不曲折、够坚韧,颠覆了生命对现实生活的迎合性态势,植根于生命意志的本能冲动。拥有这些"方性"人格的小人物在现实生活中,在追求"是与非"的碰撞中遭受的多是毁灭性的摧毁,这体现了这些小人物力量的弱小和自身的不可存在性,然而正是这些不可存在性成为了我们社会发展的动力,求新求变的作用力,以及起到对人性进行追问与反思的作用。 展开更多
关键词 《瓦城三部曲》 方性”人格 美学价值
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Normalized Solutions of Nonlinear Choquard Equations with Nonconstant Potential
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作者 LI Nan XU Liping 《应用数学》 北大核心 2025年第1期14-29,共16页
In this paper,we mainly focus on a type of nonlinear Choquard equations with nonconstant potential.Under appropriate hypotheses on potential function and nonlinear terms,we prove that the above Choquard equation with ... In this paper,we mainly focus on a type of nonlinear Choquard equations with nonconstant potential.Under appropriate hypotheses on potential function and nonlinear terms,we prove that the above Choquard equation with prescribed 2-norm has some normalized solutions by introducing variational methods. 展开更多
关键词 Nonlinear Choquard equation Potential function Variational method Normalized solution
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Two Second-Order Ecient Numerical Schemes for the Boussinesq Equations
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作者 LIU Fang WANG Danxia ZHANG Jianwen 《应用数学》 北大核心 2025年第1期114-129,共16页
In this paper,we construct two fully decoupled,second-order semi-discrete numerical schemes for the Boussinesq equations based on the scalar auxiliary variable(SAV)approach.By introducing a scalar auxiliary variable,t... In this paper,we construct two fully decoupled,second-order semi-discrete numerical schemes for the Boussinesq equations based on the scalar auxiliary variable(SAV)approach.By introducing a scalar auxiliary variable,the original Boussinesq system is transformed into an equivalent one.Then we discretize it using the second-order backward di erentiation formula(BDF2)and Crank-Nicolson(CN)to obtain two second-order time-advanced schemes.In both numerical schemes,a pressure-correction method is employed to decouple the velocity and pressure.These two schemes possess the desired property that they can be fully decoupled with satisfying unconditional stability.We rigorously prove both the unconditional stability and unique solvability of the discrete schemes.Furthermore,we provide detailed implementations of the decoupling procedures.Finally,various 2D numerical simulations are performed to verify the accuracy and energy stability of the proposed schemes. 展开更多
关键词 Scalar auxiliary variable approach Pressure-correction method Fully decoupled Unconditional stability Boussinesq equations
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A class of quasilinear equations with-1 powers
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作者 ZHANG Heng SUN Yijing 《中国科学院大学学报(中英文)》 北大核心 2025年第1期13-19,共7页
This paper deals with quasilinear elliptic equations of singular growth like-Δu-uΔ(u^(2))=a(x)u^(-1).We establish the existence of positive solutions for general a(x)∈L^(p)(Ω),p>2,whereΩis a bounded domain inℝ... This paper deals with quasilinear elliptic equations of singular growth like-Δu-uΔ(u^(2))=a(x)u^(-1).We establish the existence of positive solutions for general a(x)∈L^(p)(Ω),p>2,whereΩis a bounded domain inℝ^(N)with N≥1. 展开更多
关键词 quasilinear singular equation -1 power elliptic equation
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深层页岩储层裂缝识别及有效性评价方法研究及应用——以四川盆地南部为例
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作者 邱小雪 石学文 +5 位作者 廖茂杰 张洞君 高翔 杨杨 钟光海 刘鹏 《油气藏评价与开发》 北大核心 2025年第1期40-48,55,共10页
四川盆地南部地区(以下简称川南)深层页岩储层断裂发育,直接影响页岩气水平井的工程施工和有效建产。基于川南五峰组—龙马溪组页岩岩心,开展岩石物理实验和数值模拟实验,得到了不同尺度、不同产状、不同充填物质的裂缝声学响应特征,分... 四川盆地南部地区(以下简称川南)深层页岩储层断裂发育,直接影响页岩气水平井的工程施工和有效建产。基于川南五峰组—龙马溪组页岩岩心,开展岩石物理实验和数值模拟实验,得到了不同尺度、不同产状、不同充填物质的裂缝声学响应特征,分析了裂缝对声波衰减能力的影响因素,建立了1套页岩气水平井裂缝识别和有效性评价方法。结果表明:纵波、横波和斯通利波的振幅衰减受裂缝倾角和裂缝宽度的共同影响,其衰减能力随裂缝宽度增加呈指数增加,随裂缝倾角的增加而降低。斯通利波对充填流体裂缝敏感,可识别和评价含气、含水的有效裂缝;纵波和偶极横波对充填方解石裂缝敏感,可识别和评价充填方解石的无效裂缝。基于反射波成像识别的裂缝结果与成像测井、岩心识别裂缝类型一致,验证了有效性评价方法的可靠性。将研究成果应用于页岩气水平井实测资料,精细评价了页岩气水平井断裂风险位置,有效保障了“一段一策”压裂分段的优化设计。 展开更多
关键词 裂缝 深层页岩 阵列声波 振幅衰减 有效性评价
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The preparation and properties of N-doped carbon materials and their use for sodium storage
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作者 YUAN Ren-lu HOU Ruo-yang +4 位作者 SHANG Lei LIU Xue-wei LI Ang CHEN Xiao-hong SONG Huai-he 《新型炭材料(中英文)》 SCIE EI CAS CSCD 北大核心 2024年第5期770-795,共26页
Defect engineering by heteroatom doping gives carbon materials some new characteristics such as a different electronic structure and a high electrochemical activity,making them suitable for high-performance applicatio... Defect engineering by heteroatom doping gives carbon materials some new characteristics such as a different electronic structure and a high electrochemical activity,making them suitable for high-performance applications.N-doping has been widely investigated because of its similar atom radius to carbon,high electronegativity as well as many different configurations.We summarize the preparation methods and properties of N-doped carbon materials,and discuss their possible use in sodium ion storage.The relationships between N content/configuration and crystallinity,electronic conductivity,wettability,chemical reactivity as well as sodium ion storage performance are discussed. 展开更多
关键词 N-doped carbon material N configuration Preparation method Performance Sodium storage
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The modulating of Qingguang’anⅡFormula on gut microbiota in mice with chronic high intraocular pressure by 16S rDNA sequencing
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作者 ZHOU Yasha GAO Wenyong +5 位作者 HUANG Yu XIA Xin XIAO Li DENG Ying PENG Qinghua PENG Jun 《Digital Chinese Medicine》 CSCD 2024年第4期332-342,共11页
Objective To investigate the effects of Qingguang'anⅡFormula(QGAⅡ)on the gut micro-biota of mice with chronic high intraocular pressure(IOP)model,and explore its key micro-biota for protecting the optic nerve.Me... Objective To investigate the effects of Qingguang'anⅡFormula(QGAⅡ)on the gut micro-biota of mice with chronic high intraocular pressure(IOP)model,and explore its key micro-biota for protecting the optic nerve.Methods A total of 10 specific pathogen free(SPF)grade female DBA/2J mice were random-ly divided into model group and QGAⅡgroup(n=5 for each group),while additional 5 SPF-grade female C57BL/6J mice were assigned to control group.Mice presented spontaneous high IOP and showed elevated approximately at the age of seven months.The high IOP was maintained until week 38,when gavage was initiated.Mice in control group underwent the same intragastric treatment,while those in QGAⅡgroup were gavaged with QGAⅡ(9.67 g/kg),once a day for four weeks.Retinal morphology was examined using hematoxylin and eosin(HE)staining,with the number of retinal ganglion cells(RGCs)counted.The expression level of Brn3a protein,a specific marker for RGCs,was detected by immunofluorescence,with the mean optical density(OD)measured for quantitative analysis.In addition,16S rDNA se-quencing was leveraged to analyze changes in the diversity of gut microbiota,including theirα-diversity(Chao1,Shannon,Pielou’s evenness,and observed species index)andβ-diversity.Venn diagrams and linear discriminant analysis effect size(LEfSe)analysis was employed to investigate the number of amplicon sequence variants(ASVs),the abundance of differential gut microbiota species,and the classification of species at both the phylum and genus levels within the three groups of mice.Results HE staining revealed that compared with control group,model group showed signif-icant reduction in the number of RGCs(P<0.01),with intracellular vacuolar degeneration and nuclear pyknosis.After QGAⅡtreatment,the number of RGCs was significantly in-creased compared with model group(P<0.01),with notable improvements in intracellular vacuolar degeneration.Immunofluorescence analysis showed that the mean OD of Brn3a protein was significantly decreased in model group compared with control group(P<0.01),while QGAⅡtreatment significantly elevated its expression level(P<0.01).Analysis ofα-diversity showed that after QGAⅡintervention,the Chao1,Shannon,and Pielou’s evenness indices were significantly increased(P<0.01),and the observed species index was elevated(P<0.05).β-Diversity analysis demonstrated distinct clustering among the three groups,indicating relatively low similarity in bacterial community structures.ASV clustering identi-fied a total of 14061 ASVs across all groups,with 9514 ASVs shared between model and QGAⅡgroups.At the phylum level,the abundance of Bacteroidetes was significantly decreased in model group compared with control group(P<0.01),while Firmicutes and the Firmicutes/Bacteroidetes(F/B)ratio were significantly increased(P<0.01).QGAⅡtreatment significantly reduced both Firmicutes abundance and the F/B ratio(P<0.01).At the genus level,Lactobacillus was dominant across all groups,with its abundance significantly in-creased in model group(P<0.01)and subsequently decreased following QGAⅡintervention(P<0.05).Conclusion QGAⅡrestructured the gut microbiota of DBA/2J mice with chronic high IOP,bringing changes in their diversity and abundance of components.Firmicutes,Bacteroidetes,Lactobacillus,along with their associated microorganisms,are likely critical components of the gut microbiota that contribute to the optic neuroprotective effects of QGAⅡon chronic high IOP mice. 展开更多
关键词 Qingguang’anⅡFormula Chronic high intraocular pressure 16S rDNA sequencing Optic neuroprotection Gut microbiota
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On the Local Convergence and Dynamics of New Iterative Method with Sixth Order Convergence
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作者 Lyu Borui Chu Xue Wang Haijun 《数学理论与应用》 2024年第3期50-66,共17页
In this paper,we construct a new sixth order iterative method for solving nonlinear equations.The local convergence and order of convergence of the new iterative method is demonstrated.In order to check the validity o... In this paper,we construct a new sixth order iterative method for solving nonlinear equations.The local convergence and order of convergence of the new iterative method is demonstrated.In order to check the validity of the new iterative method,we employ several chemical engineering applications and academic test problems.Numerical results show the good numerical performance of the new iterative method.Moreover,the dynamical study of the new method also supports the theoretical results. 展开更多
关键词 Nonlinear equation Sixth order method Local convergence Basin of attraction
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Musielak-Orlicz序列空间的非方常数 被引量:1
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作者 赵亮 崔云安 《哈尔滨商业大学学报(自然科学版)》 CAS 2006年第2期112-114,共3页
给出了Musielak-Orlicz序列空间的非方常数表达式.得到的结果为:当M∈δ02时,则CJl0M=sup infk>1Cx.y.k>0∶PMk(x+y)Cx.y.k=k-1∶x,y∈S(l0M),‖x+y‖0=‖x+y‖0CJlM=supCx.y>0∶PMx+yCx.y=1,x,y∈S(lM),‖x+y‖=‖x-y‖.
关键词 BANACH空间 MUSIELAK-ORLICZ序列空间 方性 非方常数
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Flotation separation of brucite and calcite in dodecylamine system enhanced by regulator potassium dihydrogen phosphate
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作者 Xiu-feng GONG Jin YAO +3 位作者 Bin YANG Wan-zhong YIN Yu-lian WANG Ya-feng FU 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第8期2658-2670,共13页
To achieve efficient flotation separation of brucite and calcite,flotation separation experiments were conducted on two minerals using dodecylamine(DDA)as the collector and potassium dihydrogen phosphate(PDP)as the re... To achieve efficient flotation separation of brucite and calcite,flotation separation experiments were conducted on two minerals using dodecylamine(DDA)as the collector and potassium dihydrogen phosphate(PDP)as the regulator.The action mechanism of DDA and PDP was explored through contact angle measurement,zeta potential detection,solution chemistry calculation,FTIR analysis,and XPS detection.The flotation results showed that when DDA dosage was 35 mg/L and PDP dosage was 40 mg/L,the maximum floating difference between brucite and calcite was 79.81%,and the selectivity separation index was 6.46.The detection analysis showed that the main dissolved component HPO_(4)^(2−)of PDP is selectively strongly adsorbed on the Ca site on the surface of calcite,promoting the adsorption of the main dissolved component RNH_(3)^(+)of DDA on calcite surface,while brucite is basically not affected by PDP.Therefore,PDP is an effective regulator for the reverse flotation separation of brucite and calcite in DDA system. 展开更多
关键词 BRUCITE CALCITE selective adsorption flotation separation
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Dynamics of Nonlinear Waves in(2+1)-Dimensional Extended Boiti-Leon-Manna-Pempinelli Equation
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作者 SUN Junxiu WANG Yunhu 《应用数学》 北大核心 2024年第4期1103-1113,共11页
Based on the Hirota bilinear method,this study derived N-soliton solutions,breather solutions,lump solutions and interaction solutions for the(2+1)-dimensional extended Boiti-Leon-Manna-Pempinelli equation.The dynamic... Based on the Hirota bilinear method,this study derived N-soliton solutions,breather solutions,lump solutions and interaction solutions for the(2+1)-dimensional extended Boiti-Leon-Manna-Pempinelli equation.The dynamical characteristics of these solutions were displayed through graphical,particularly revealing fusion and ssion phenomena in the interaction of lump and the one-stripe soliton. 展开更多
关键词 Hirota bilinear method N-soliton solutions Breather solutions Lump solutions Interaction solutions (2+1)-dimensional extended Boiti-Leon-Manna-Pempinelli equation
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论本科教学评估与高质量人才的培养 被引量:3
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作者 邓楠 《当代教育论坛(宏观教育研究)》 2005年第05S期89-90,共2页
本科教学水平评估是加强高校建设和提高教学质量的重要举措,充分认识其重要性,以本科教学评估为契机,创新性地开展工作,培养高质量的人才,这是地方性本科院校当前的一项重要的任务。
关键词 本科 教学评估 高质量人才 教学质量 方性本科院校 教学基本建设 教学管理
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Numerical modelling for predicting corrosion initiation life of reinforced concrete square piles under reverse-seepage pressure
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作者 WANG Rong-bo WU Wen-bing +3 位作者 HE Si-hong XIAO Liang WEN Min-jie MEI Guo-xiong 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第10期3596-3611,共16页
Square piles of reinforced concrete(RC)in marine environments are susceptible to chloride-inducedcorrosion.A novel reverse-seepage technique(RST)is applied to square piles to block the intrusion of chlorides.Thisresea... Square piles of reinforced concrete(RC)in marine environments are susceptible to chloride-inducedcorrosion.A novel reverse-seepage technique(RST)is applied to square piles to block the intrusion of chlorides.Thisresearch introduces a computational model designed to predict the lifespan of corrosion initiation in reinforced concretesquare piles when applied reverse-seepage pressure.The model considers the impacts of chloride binding and the tripletime-dependence property among the permeability,the corrected surface chloride concentration,and the diffusioncoefficient.The proposed numerical model is solved using the alternating direction implicit(ADI)approach,and itsaccuracy and reliability are evaluated by contrasting the computational outcomes with the analytical solution andexperimental results.Furthermore,the primary factors contributing to the corrosion of reinforced concrete square pilesare analyzed.The results indicate that applying RST can decrease the chloride penetration depth and prolong the lifespanof corrosion initiation in square piles.The water-cement ratio and reverse seepage pressure are the most influentialfactors.A water pressure of 0.4 MPa can double the life of concrete,and the durable life of concrete with a water-cementratio of 0.3 can reach 100 years. 展开更多
关键词 reverse-seepage technique chloride ion intrusion alternating direction implicit method reinforced concrete square pile corrosion initiation life
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社区卫生服务中医疗纠纷的防范
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作者 李晖 胡晓雯 邵荣 《青岛医药卫生》 2005年第1期73-74,共2页
关键词 社区卫生服务 医疗纠纷 防范 医源性因素 社会性因素 方性因素
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Asymptotic behavior of solutions of a parabolic equations in a band domain
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作者 DU Wenjing HUANG Xinyu +2 位作者 WU Junyan XIU Xinxiu YUAN Lixia 《上海师范大学学报(自然科学版中英文)》 2024年第6期719-724,共6页
consider a quasilinear parabolic equation in a band domain with inhomogeneous and unbounded boundary conditions.We show that,under certain conditions,the solution u of the initialboundary value problem tends to infini... consider a quasilinear parabolic equation in a band domain with inhomogeneous and unbounded boundary conditions.We show that,under certain conditions,the solution u of the initialboundary value problem tends to infinite as t→∞.Moreover,by using the zero number argument we show that for any x≠O,u_(x)(x,t)also tends as t→∞to infinity,that is,the gradient is asymptotically unbounded. 展开更多
关键词 curvature flow quasilinear parabolic equation translating solution asymptotic behavior
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Stability analysis of three-dimensional two-bench unsaturated soil slopes under seismic loading
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作者 SHAN Jun-tao WU Yi-min YANG Xiao-li 《Journal of Central South University》 CSCD 2024年第11期4187-4202,共16页
Due to rainfall infiltration,groundwater activity,geological processes,and natural erosion,soil often exhibits heterogeneity and unsaturation.Additionally,seismic events can compromise slope stability.Existing analyti... Due to rainfall infiltration,groundwater activity,geological processes,and natural erosion,soil often exhibits heterogeneity and unsaturation.Additionally,seismic events can compromise slope stability.Existing analytical solutions typically consider a single failure mode,leading to inaccurate slope stability assessments.This study analyzes the impact of matric suction through three nonlinear shear strength models and adopts a heterogeneous soil model where cohesion linearly increases with depth.An improved pseudo-dynamic method is used to account for seismic effects.Based on a three-dimensional(3D)trumpet-shaped rotational failure mechanism,a new framework is established to analyze the stability of 3D two-bench slopes in heterogeneous unsaturated soil under seismic effects.The internal energy dissipation rate and external power at failure are calculated,and the gravity increase method is introduced to derive an explicit expression for the safety factor(F_(s)).The results are compared with previously published results,demonstrating the effectiveness of the proposed method.Sensitivity analyses on different parameters are conducted,discussing the influence of various factors on F s.This study proposes a new formula for calculating the F_(s) of 3D two-bench slopes in heterogeneous unsaturated soil under seismic effects,providing a practical application for slope engineering. 展开更多
关键词 3D two-bench slope limit analysis modified pseudo-dynamic method HETEROGENEITY UNSATURATION
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