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鄂尔多斯盆地东缘上古生界致密储层含气系统压力演化 被引量:2
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作者 李勇 朱治同 +2 位作者 吴鹏 申陈州 高计县 《石油与天然气地质》 EI CAS CSCD 北大核心 2023年第6期1568-1581,共14页
鄂尔多斯盆地东缘上古生界多层系致密气发育,准确认识气藏压力演化过程对深化致密气成藏认识和实现气井高产稳产具有指导意义。综合应用钻测井资料和岩心流体包裹体测试,结合盆地埋藏史和热演化史模拟,揭示了鄂尔多斯盆地东缘上古生界... 鄂尔多斯盆地东缘上古生界多层系致密气发育,准确认识气藏压力演化过程对深化致密气成藏认识和实现气井高产稳产具有指导意义。综合应用钻测井资料和岩心流体包裹体测试,结合盆地埋藏史和热演化史模拟,揭示了鄂尔多斯盆地东缘上古生界含气系统压力演化。结果显示,研究区自下而上发育欠压、略微欠压和常压系统。均一温度和盐度总体上连续分布,反映了油气连续充注过程。太原组、山西组和下石盒子组均一温度和盐度正相关,反映近源生烃后快速充注;上石盒子组和石千峰组均一温度和盐度负相关,受流体远距离运移充注和紫金山构造热事件作用下的气藏再平衡影响。研究区在白垩纪中期大量生烃,形成了异常高压,储层压力在34.89~38.26 MPa。后期地层抬升造成储层压力降低,其中地层降温贡献了50.31%~57.85%;天然气膨胀引起的气体运移贡献了28.25%~41.95%,且以上部地层降低为主;孔隙反弹贡献了0.37%~0.79%。相关成果系统揭示了上古生界致密气藏压力系统演化及现今气藏压力成因,对于认识鄂尔多斯盆地和类似盆地致密气富集成藏规律具有借鉴意义。 展开更多
关键词 流体包裹体 压力系统 致密气 上古生界 临兴地区 鄂尔多斯盆地
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Asymptotic upper bounds for wheel:complete graph Ramsey numbers
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作者 宋洪雪 《Journal of Southeast University(English Edition)》 EI CAS 2004年第1期126-129,共4页
It is shown that r(W_m, K_n)≤(1+o(1))C_1n log n 2m-2m-2 for fixed even m≥4 and n→∞, and r(W_m, K_n)≤(1+o(1))C_2n 2mm+1 log n m+1m-1 for fixed odd m≥5 and n→∞, wher... It is shown that r(W_m, K_n)≤(1+o(1))C_1n log n 2m-2m-2 for fixed even m≥4 and n→∞, and r(W_m, K_n)≤(1+o(1))C_2n 2mm+1 log n m+1m-1 for fixed odd m≥5 and n→∞, where C_1=C_1(m)>0 and C_2=C_2(m)>0, in particular, C_2=12 if m=5 . It is obtained by the analytic method and using the function f_m(x)=∫ 1 _ 0 (1-t) 1m dtm+(x-m)t , x≥0 , m≥1 on the base of the asymptotic upper bounds for r(C_m, K_n) which were given by Caro, et al. Also, cn log n 52 ≤r(K_4, K_n)≤(1+o(1)) n 3 ( log n) 2 (as n→∞ ). Moreover, we give r(K_k+C_m, K_n)≤(1+o(1))C_5(m)n log n k+mm-2 for fixed even m≥4 and r(K_k+C_m, K_n)≤(1+o(1))C_6(m)n 2+(k+1)(m-1)2+k(m-1) log n k+2m-1 for fixed odd m≥3 (as n→∞ ). 展开更多
关键词 Ramsey numbers WHEELS independent number complete graphs
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Upper Bounds for the L_p-norms of the Maximal Functions of Martingales
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作者 曾六川 《Chinese Quarterly Journal of Mathematics》 CSCD 2002年第1期77-84,共8页
Let 2≤p【∞ and let (f n) be a martingale. Using exponential bounds of the probabilities of the type P(|f n|】λ‖T(f n)‖ ∞) for some quasi-linear operators acting on martingales, we estimate upper bounds for t... Let 2≤p【∞ and let (f n) be a martingale. Using exponential bounds of the probabilities of the type P(|f n|】λ‖T(f n)‖ ∞) for some quasi-linear operators acting on martingales, we estimate upper bounds for the L p-norms of the maximal functions of martinglaes. Our result is the extension and improvements of the results obtained previously by HITCZENKO and ZENG . 展开更多
关键词 MARTINGALE stopping time maximal function L p-norm
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论青主的艺术形上学思想
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作者 冯学勤 《艺术学研究》 2022年第5期98-107,共10页
现代艺术形上学是一种关于艺术的超越性价值论,是指艺术具有超越道德、政治和经济等一般社会性功能的信仰价值,并被放置在原本由道德或宗教所占据的最高价值的王座之上。青主构建了分属自然、主体和超主体的“三界”观,提出了“音乐是... 现代艺术形上学是一种关于艺术的超越性价值论,是指艺术具有超越道德、政治和经济等一般社会性功能的信仰价值,并被放置在原本由道德或宗教所占据的最高价值的王座之上。青主构建了分属自然、主体和超主体的“三界”观,提出了“音乐是上界的声音”“灵魂向灵魂述说的语言”等典型的艺术形上学命题。青主的艺术形上学思想,其当代意义在于为本土现代音乐理论贡献了一种比较系统的、纯粹的超越性价值话语,并跨越了通过思想文化变革以实现救亡图存的特殊历史语境,在新时代为民众价值信仰建构提供启示。 展开更多
关键词 青主 艺术形上学 《乐话·音乐通论》 “上界” 乐艺之神
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On the Second-order Item Coefficients for ε-starlike Mappings in C^n 被引量:1
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作者 尹清杰 罗萍 《Chinese Quarterly Journal of Mathematics》 CSCD 2002年第4期78-82,共5页
Let B n be the unit ball in C n, we study ε-starlike mappings on B n. The upper bounds of second order item coefficients of homogeneous expansion for ε-starlike mappings are obtained.
关键词 starlike mappings homogeneous expansion
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Upper bound analysis of slope stability with nonlinear failure criterion based on strength reduction technique 被引量:24
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作者 赵炼恒 李亮 +2 位作者 杨峰 罗强 刘项 《Journal of Central South University》 SCIE EI CAS 2010年第4期836-844,共9页
Based on the upper bound limit analysis theorem and the shear strength reduction technique, the equation for expressing critical limit-equilibrium state was employed to define the safety factor of a given slope and it... Based on the upper bound limit analysis theorem and the shear strength reduction technique, the equation for expressing critical limit-equilibrium state was employed to define the safety factor of a given slope and its corresponding critical failure mechanism by means of the kinematical approach of limit analysis theory. The nonlinear shear strength parameters were treated as variable parameters and a kinematically admissible failure mechanism was considered for calculation schemes. The iterative optimization method was adopted to obtain the safety factors. Case study and comparative analysis show that solutions presented here agree with available predictions when nonlinear criterion reduces to linear criterion, and the validity of present method could be illuminated. From the numerical results, it can also be seen that nonlinear parameter rn, slope foot gradient ,β, height of slope H, slope top gradient a and soil bulk density γ have significant effects on the safety factor of the slope. 展开更多
关键词 nonlinear failure criterion strength reduction method upper-bound theorem of limit analysis slope stability analysis factor of safety
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Three-dimensional stability analysis of anisotropic and non-homogeneous slopes using limit analysis 被引量:6
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作者 韩长玉 陈锦剑 +1 位作者 夏小和 王建华 《Journal of Central South University》 SCIE EI CAS 2014年第3期1142-1147,共6页
A method of three-dimensional loaded slope stability for anisotropic and nonhomogeneous slopes was presented based on the upper-bound theorem of the limit analysis approach. The approach can be considered as a modific... A method of three-dimensional loaded slope stability for anisotropic and nonhomogeneous slopes was presented based on the upper-bound theorem of the limit analysis approach. The approach can be considered as a modification and extension of the solutions. The influences of friction angle, anisotropy factor, nonhomogeneous factor, slope angle, ratio of width to depth, and load on the slope crest were investigated. The results show that solutions are suitable to deal with the purely cohesive soils and frictional/cohesive soils, isotropic and anisotropic, homogeneous and nonhomogeneous, loaded and unloaded cases. 展开更多
关键词 stability ANISOTROPY limit analysis loaded slope nonhomogeneous slope
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Upper bound seismic rotational stability analysis of gravity retaining walls considering embedment depth 被引量:2
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作者 刘杰 黄达 +1 位作者 杨超 孙莎 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第10期4083-4089,共7页
Stability analysis of gravity retaining wall was currently based on the assumption that the wall had no embedment depth. The effect of earth berm was usually neglected. The present work highlighted the importance of e... Stability analysis of gravity retaining wall was currently based on the assumption that the wall had no embedment depth. The effect of earth berm was usually neglected. The present work highlighted the importance of embedment depth when assessing the seismic stability of gravity retaining walls with the pattern of pure rotation. In the framework of upper bound theorem of limit analysis, pseudo-static method was applied into two groups of parallel rigid soil slices methods in order to account for the effect of embedment depth on evaluating the critical acceleration of wall-soil system. The present analytical solution is identical to the results obtained from using limit equilibrium method, and the two methods are based on different theory backgrounds. Parameter analysis indicates that the critical acceleration increases slowly when the ratio of the embedment depth to the total height of the wall is from 0 to 0.15 and increases drastically when the ratio exceeds 0.15. 展开更多
关键词 gravity retaining wall embedment depth seismic rotational stability upper bound analysis parallel rigid soil slices
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An upper bound analysis of rolling process of non-bonded sandwich sheets 被引量:1
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作者 Heshmatollah HAGHIGHAT Pedram SAADATI 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第5期1605-1613,共9页
Rolling process of symmetrical non-bonded sandwich sheets was investigated by the method of upper bound. A deformation model was proposed and the mathematical relations of the velocity components were developed. The i... Rolling process of symmetrical non-bonded sandwich sheets was investigated by the method of upper bound. A deformation model was proposed and the mathematical relations of the velocity components were developed. The internal, shear and frictional power terms were derived and used in the upper bound model. Through the analysis, the rolling force, mean contact pressure and final thickness of each layer were determined. The validity of the proposed analytical model was discussed by comparing the theoretical predictions with the experimental data found in the literatures. Effects of various rolling conditions such as the flow stress ratio, initial thickness ratio of the raw sheets and total thickness reduction upon the rolling torque were analyzed. The accuracy of the developed analytical model was very high. 展开更多
关键词 flat rolling sandwich sheet upper bound method
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A Lower and Upper Bound Method for Complex System Reliability Evaluation 被引量:1
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作者 魏展明 周凡 陈耀武 《Journal of Donghua University(English Edition)》 EI CAS 2011年第5期445-450,共6页
It is hard for the existing methods to obtain the expression of the system reliability for most of the practical complex systems with a large number of components and possible stales. A new regression algorithm based ... It is hard for the existing methods to obtain the expression of the system reliability for most of the practical complex systems with a large number of components and possible stales. A new regression algorithm based on the lower and upper bounds is presented in this paper, which can obtain the system reliability analytically without concerning the structure of the complex system. The method has been applied to a real system and the reliability results are compared with those acquired by the classical method and the parametric method. The effectiveness and accuracy of the proposed method have been testified. 展开更多
关键词 RELIABILITY lower bound upper bound regression algorithm
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Software Composition of Different Security Level Components 被引量:1
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作者 Frank Tsui Edward Jung Sheryl Duggins 《Computer Technology and Application》 2011年第11期835-842,共8页
In this paper the authors show how software component design can affect security properties through different composition operators. The authors define software composition as the result of aggregating and/or associat... In this paper the authors show how software component design can affect security properties through different composition operators. The authors define software composition as the result of aggregating and/or associating a component to a software system. The component itself may be informational or functional and carry a certain level of security attribute. The authors first show that the security attributes or properties form a lattice structure when combined with the appropriate least upper bound and greatest lower bound type of operators. Three composition operators, named C l, C2 and C3 are developed. The system's security properties resulting from these compositions are then studied. The authors discuss how different composition operators maintain, relax and restrict the security properties. Finally, the authors show that C1 and C2 composition operators are order-sensitive and that C3 is order-insensitive. 展开更多
关键词 Software composition SECURITY component-design.
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Trend and Interannual Variability of Chinese Air Pollution since 2000 in Association with Socioeconomic Development: A Brief Overview 被引量:7
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作者 LIN Jin-Tai PAN Da ZHANG Rui-Xiong 《Atmospheric and Oceanic Science Letters》 CSCD 2013年第2期84-89,共6页
Abstract Chinese air pollution has increased in this century along with the rapid socioeconomic development and resulting anthropogenic emissions. While recent emission control measures have shown encouraging re sults... Abstract Chinese air pollution has increased in this century along with the rapid socioeconomic development and resulting anthropogenic emissions. While recent emission control measures have shown encouraging re sults and have reduced the levels of sulfur dioxide and primary aerosols, the concentrations of other air pollutants continue to grow, particularly secondary pollutants in cluding ozone and secondary aerosols. Meanwhile, a va riety of intentional and unintentional socioeconomic events have temporarily changed the pace, and even the signs, of growth of air pollution. These events include the short-term emission restrictions imposed during the Sino-African Summit, the Beijing Olympics and Para lympics, the Shanghai World Exposition (Shanghai Expo), the Guangzhou Asian Olympics, and the Shenzhen Uni versiade, as well as the unintentional emission reductions associated with the recent economic recession and the annual Chinese New Year. This paper presents a brief overview of trends and temporary perturbations of Chi nese air pollution since 2000, summarizing studies on anthropogenic emission inventories, atmospheric meas urements, and inverse modeling. It concludes with rec ommendations for future research. 展开更多
关键词 air pollution trend and variability socioeconomic development satellite measurements bottom-upemission inventories top-down constraints
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Upper Bound and Lower Bound Estimate of Monotone Increasing Fractal Function
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作者 MA Guan-zhong YUAN Gui-xia CUI Zhen-wen 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2008年第2期188-194,共7页
Mass distribution principle is one of important tools in studying Hausdorff dimension and Hausdorff measure. In this paper we will give a numerical approximate method of upper bound and lower bound of mass distributio... Mass distribution principle is one of important tools in studying Hausdorff dimension and Hausdorff measure. In this paper we will give a numerical approximate method of upper bound and lower bound of mass distribution function f(x)(it is a monotone increasing fractal function) and its some applications. 展开更多
关键词 FRACTAL mass distribution function iterated function system piecewise anti- Bezier curve
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Some New Properties of Wigner Function Studied in Entangled State Representation
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作者 范洪义 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第8期241-243,共3页
Based on the Wigner operator in the entangled state representation we study some new important propertiesof Wigner function for bipartite entangled systems,such as size of an entangled state,upper bound of Wigner func... Based on the Wigner operator in the entangled state representation we study some new important propertiesof Wigner function for bipartite entangled systems,such as size of an entangled state,upper bound of Wigner functions,etc.These discussions demonstrate the beauty and elegance of the entangled state representation. 展开更多
关键词 Wigner function entangled state representation Wigner operator
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On Estimation of Fully Entangled Fraction
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作者 谷瑞娟 李明 +1 位作者 费少明 李先清 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第2期265-268,共4页
We study the fully entangled fraction (FEF) of arbitrary mixed states. New upper bounds of FEF are derived. These upper bounds make complements on the estimation of the value of FEF. For weakly mixed quantum states,... We study the fully entangled fraction (FEF) of arbitrary mixed states. New upper bounds of FEF are derived. These upper bounds make complements on the estimation of the value of FEF. For weakly mixed quantum states, an upper bound is shown to be very tight to the exact value of FEF. 展开更多
关键词 ENTANGLEMENT fully entangled fraction
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On the Optimality of Kounias-Sotirakglou Bounds
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作者 李寿德 田增瑞 顾孟迪 《Journal of Donghua University(English Edition)》 EI CAS 2007年第1期133-136,共4页
Bonferroni inequalities are significant in application for optimal allocation in tradable emission and other scary resources. Kounias and Sotirakglou improved Bonferroni inequalities, they give the lower and upper bou... Bonferroni inequalities are significant in application for optimal allocation in tradable emission and other scary resources. Kounias and Sotirakglou improved Bonferroni inequalities, they give the lower and upper bounds for Bonferroni inequalities in the form of P(Ui=1^nAi),but they did not discuss the optimal of lower and upper bounds for P(Ui=1^nAi).In this paper, we give the method to obtain the optimum lower and upper bounds for Bonferroai inequalities in the form of ∑i=1^m(-1)^i+1 aiSi for P(Ui=1^nAi)under the condition tha Q(r)≥(≤)0,The optimality of Kounias Sotirakglou bounds is also studied. 展开更多
关键词 Bon f erroni inequalities Kounias-Sotirakglou bounds Linear programming.
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Asymptotic Behavior of Super Brownian Motion
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作者 阎国军 马建国 《Chinese Quarterly Journal of Mathematics》 CSCD 2002年第3期9-17,共9页
Generally, super Brownian motion will not c on verge vaguely to 0 if the initial measure is sufficiet large, so it is very inte resting to get asymptotic estimation for super Brownian motion. In this paper, w e will p... Generally, super Brownian motion will not c on verge vaguely to 0 if the initial measure is sufficiet large, so it is very inte resting to get asymptotic estimation for super Brownian motion. In this paper, w e will prove two asymptotic for super Brownian motion with general critical bran ching mechanism. 展开更多
关键词 super Brownian motion super martingale inequality cr itical branching mechanism
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WentzeI-Freidlin Estimates for Jump Processes in Semi-Group Theory: Upper Bound
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作者 Remi Leandre 《Computer Technology and Application》 2011年第4期329-332,共4页
Large deviations estimates for Poisson processes estimate the logarithm of rare events associated to a Poisson process which has more and more jump which are smaller and smaller. In stochastic analysis, they are valid... Large deviations estimates for Poisson processes estimate the logarithm of rare events associated to a Poisson process which has more and more jump which are smaller and smaller. In stochastic analysis, they are valid on the whole path space. Asoociated to this jump process is a Markov semi-group. We translate in semi group theory the proof of Wentzel-Freidlin for these estimates by translating in semi-group theory some basical tools of stochastic analysis as the exponential martingales of stochastic analysis. These Wentzel-Freidlin estimates (upper-bound) are only true for the semi-group. 展开更多
关键词 Large deviations poisson processes semi-groups.
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An Upper Bound for the Number of Normalized Latin Square
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作者 DUAN Lian 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2006年第4期585-589,共5页
In this note, the author find an upper bound formula for the number of the p × p normalized Latin Square,the first row and column of which are both standard order 1, 2,…p.
关键词 Latin square normalized latin square inclusion-exclusion principe
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The Upper Bound of the Moebius Scalar Curvature of Submanifolds in S^n+p
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作者 ZHONG Ding-xing SUN Hong-an MO Xiao-kai 《Chinese Quarterly Journal of Mathematics》 CSCD 2010年第1期65-73,共9页
The most important Moebius invariants in the Moebius differential geometry of submanifolds in S^n+p are the Moebius metric g, the Moebius second fundamental form B, the Moebius form φ and the Blaschke tensor A. In t... The most important Moebius invariants in the Moebius differential geometry of submanifolds in S^n+p are the Moebius metric g, the Moebius second fundamental form B, the Moebius form φ and the Blaschke tensor A. In this paper, we obtain the upper bound of the Moebius scalar curvature of submanifolds with parallel Moebius form in S^n+p. 展开更多
关键词 upper bound Moebius metric Moebius scalar curvature parallel Moebius form
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