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Modification of rock mass rating system:Interbedding of strong and weak rock layers 被引量:7
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作者 Mohammad Mohammadi Mohammad Farouq Hossaini 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2017年第6期1165-1170,共6页
Rock mass classification systems are the very important part for underground projects and rock mass rating(RMR) is one of the most commonly applied classification systems in numerous civil and mining projects. The typ... Rock mass classification systems are the very important part for underground projects and rock mass rating(RMR) is one of the most commonly applied classification systems in numerous civil and mining projects. The type of rock mass consisting of an interbedding of strong and weak layers poses difficulties and uncertainties for determining the RMR. For this, the present paper uses the concept of rock bolt supporting factor(RSF) for modification of RMR system to be used in such rock mass types. The proposed method also demonstrates the importance of rock bolting practice in such rock masses. The geological parameters of the Shemshak Formation of the Alborz Tunnel in Iran are used as case examples for development of the theoretical approach. 展开更多
关键词 Rock mass rating(RMR) strong and weak rock layers Interbedding Rock bolt supporting factor(RSF) Alborz tunnel
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ON NUMBER OF LIMIT CYCLES FOR THE QUADRATIC SYSTEMS WITH A WEAK FOCUS AND A STRONG FOCUS 被引量:1
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作者 Zhang Pingguang Zhao ShenqiDept.ofMath.ZhejiangUniv.,Hangzhou310027. 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2001年第2期127-132,共6页
It is proved that the quadratic system with a weak focus and a strong focus has at most one limit cycle around the strong focus, and as the weak focus is a 2nd order(or 3rd order) weak focus the quadratic system ha... It is proved that the quadratic system with a weak focus and a strong focus has at most one limit cycle around the strong focus, and as the weak focus is a 2nd order(or 3rd order) weak focus the quadratic system has at most two(one) limit cycles which have (1,1) distribution ((0,1) distribution). 展开更多
关键词 Quadratic differential system number of limit cycle weak focus strong focus.
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Global existence of weak solutions to a prey-predator model with strong cross-diffusion
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作者 李慧玲 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2009年第6期727-740,共14页
Using finite differences and entropy inequalities, the global existence of weak solutions to a multidimensional parabolic strongly coupled prey-predator model is obtained. The nonnegativity of the solutions is also sh... Using finite differences and entropy inequalities, the global existence of weak solutions to a multidimensional parabolic strongly coupled prey-predator model is obtained. The nonnegativity of the solutions is also shown. 展开更多
关键词 prey-predator model strong cross-diffusion entropy functional existenceof weak solutions Orlicz space
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Strong/weak limits and strong/weak differentials of multi-variable indeterminate forms. I: Deduction and geometric illustration
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作者 宋光世 《Journal of Chongqing University》 CAS 2003年第2期104-108,共5页
Strong and weak limits as well as strong and weak differentials of multi-variable indeterminate forms are discussed based on the thorough exploration of differentiation to solve the strong and weak limits and differen... Strong and weak limits as well as strong and weak differentials of multi-variable indeterminate forms are discussed based on the thorough exploration of differentiation to solve the strong and weak limits and differentials of unitary indeterminate forms. The fruit of this work is going to be reported in three parts. The first part presents the standard analysis on this subject which supplements, systematizes and advances L. Hospital抯 principles on differential calculus by applying special ,general, and limit guaranteeing theories together with K(t) and XhK0 theories. The combination of theoretical analysis and geometric signification makes the derivation intuitional, visual and easy to perceive. 展开更多
关键词 strong limit weak limit strong differential weak differential indeterminate form multi-variable special form general form
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WEAKLY ALGEBRAIC REFLEXIVITY AND STRONGLY ALGEBRAIC REFLEXIVITY
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作者 Tao Changli Lu Shijie Chen PeixinDept.ofAppl.Math.,ShandongUniv.ofSci.andTech.,Taian271019,China,Dept.ofMath.,ZhejiangUniv.,Hangzhou310027,China 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2002年第2期193-198,共6页
Algebraic reflexivity introduced by Hadwin is related to linear interpolation.In this paper,the concepts of weakly algebraic reflexivity and strongly algebraic reflexivity which are also related to linear interpolat... Algebraic reflexivity introduced by Hadwin is related to linear interpolation.In this paper,the concepts of weakly algebraic reflexivity and strongly algebraic reflexivity which are also related to linear interpolation are introduced.Some properties of them are obtained and some relations between them revealed 展开更多
关键词 linear interpolation algebraic reflexivity weakly algebraic reflexivity strongly algebraic REFLEXIVITY surperreflexivity
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Checking weak and strong optimality of the solution to interval convex quadratic program
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作者 XIA Meng-xue LI Miao-miao +1 位作者 ZHANG Ben LI Hao-hao 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2021年第2期172-186,共15页
In this paper,we investigate three canonical forms of interval convex quadratic pro-gramming problems.Necessary and suficient conditions for checking weak and strong optimality of given vector corresponding to various... In this paper,we investigate three canonical forms of interval convex quadratic pro-gramming problems.Necessary and suficient conditions for checking weak and strong optimality of given vector corresponding to various forms of feasible region,are established respectively.By using the concept of feasible direction,these conditions are formulated in the form of linear systems with both equations and inequalities.In addition,we provide two specific examples to illustrate the efficiency of the conditions. 展开更多
关键词 interval convex quadratic program weakly optimal solution strongly optimal solution feasible directions
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Strong and Weak Property of Travelling Wave Front Solutions for a Class of Degenerate Parabolic Equations
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作者 李正元 刘迎东 叶其孝 《Northeastern Mathematical Journal》 CSCD 2001年第2期195-204,共10页
In this paper we study the strong and weak property of travelling wave front solutions for a class of degenerate parabolic equations. How the strong and weak property changes under the effects of wave speed and reacti... In this paper we study the strong and weak property of travelling wave front solutions for a class of degenerate parabolic equations. How the strong and weak property changes under the effects of wave speed and reaction diffusion terms are showed. 展开更多
关键词 degenerate parabolic equation strong traveling wave front solution weak traveling wave front solution convergence or divergence propety of integral
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Key Technical Points of Wheat Moisture-resistant Strain Sowing and Management of Promoting Seedlings from Weak to Strong in Daiyue District
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作者 Juqing GE 《Plant Diseases and Pests》 CAS 2022年第2期27-29,共3页
According to the meteorological conditions of sowing period and the characteristics of seedling in each key growth period,the measures of rushing drainage,rushing harvest stubble,rushing sow,implementing late sowing,s... According to the meteorological conditions of sowing period and the characteristics of seedling in each key growth period,the measures of rushing drainage,rushing harvest stubble,rushing sow,implementing late sowing,strengthening field management before winter and in spring are taken in Daiyue District during the autumn planting period of wheat,which reduce the influence of natural disasters and increase the yield of wheat. 展开更多
关键词 Moisture-resistant strain Late sowing technique Field management Promoting seedlings from weak to strong
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DIRECT TITRATION OF VERY WEAK ACIDS(BASES)IN AQUEOUS SOLUTION WITH STRONG BASES(ACIDS)USING VISUAL END-POINT INDICATION WITHOUT INDICATOR
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作者 Shu Ping BI Guang Yu ZHANG Hone GAO (H.Kao) Chemistry Department,Nanjing University,Nanjing,210008 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第2期153-154,共2页
This paper reports a new method of titration for very weak acids and bases using the appearance of incisions on oscillopolarogram to indicate the end-point.This method has the advantages of rapidity,simplicity,no indi... This paper reports a new method of titration for very weak acids and bases using the appearance of incisions on oscillopolarogram to indicate the end-point.This method has the advantages of rapidity,simplicity,no indicator needed as well as good precision. 展开更多
关键词 DIRECT TITRATION OF VERY weak ACIDS ACIDS)USING VISUAL END-POINT INDICATION WITHOUT INDICATOR BASES)IN AQUEOUS SOLUTION WITH strong BASES
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INTERACTION OF STRONG AND WEAK SINGULARITIES FOR HYPERBOLIC SYSTEM OF CONSERVATION LAWS IN MULTIDIMENSIONAL SPACE
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作者 陈恕行 《Acta Mathematica Scientia》 SCIE CSCD 1990年第3期298-302,共5页
In this paper we study the interaction of strong and weak singularities for hyperbolic system of conservation laws in multidimensional space. Under the assumption of transversal intersect of the shock front with the b... In this paper we study the interaction of strong and weak singularities for hyperbolic system of conservation laws in multidimensional space. Under the assumption of transversal intersect of the shock front with the bicharacteristics bearing weak singularities we proved a theorem on regularity propagation across the shock front. 展开更多
关键词 INTERACTION OF strong AND weak SINGULARITIES FOR HYPERBOLIC SYSTEM OF CONSERVATION LAWS IN MULTIDIMENSIONAL SPACE
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The strong versus weak theory debate in the UK advertising industry
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作者 Ziying Li 《致富时代(下半月)》 2010年第4期211-213,共3页
关键词 广告业 广告宣传 广告理论 广告策划
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基于匹配的模型卸载边缘联邦学习方法
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作者 顾永跟 张吕基 +1 位作者 吴小红 陶杰 《计算机应用研究》 北大核心 2025年第1期139-148,共10页
针对边缘计算环境下联邦学习中因资源异质性导致的“滞后者”效应等问题,提出基于匹配的模型卸载边缘联邦学习方法(Fed-MBMO)。该方法通过收集边缘设备的性能分析结果,将设备分别划分为强、弱客户端,考虑了模型训练的四个阶段时间占比,... 针对边缘计算环境下联邦学习中因资源异质性导致的“滞后者”效应等问题,提出基于匹配的模型卸载边缘联邦学习方法(Fed-MBMO)。该方法通过收集边缘设备的性能分析结果,将设备分别划分为强、弱客户端,考虑了模型训练的四个阶段时间占比,弱客户端通过冻结部分模型以节省在特征层上反向传播的时间,并将模型卸载至“强客户端”进行额外的训练,最后将强客户端模型的特征层与弱客户端的全连接层进行模型重构。为提高模型卸载效率,综合考虑模型特征层的相似度与任务完成时间构建了卸载成本矩阵,并将问题转换为迭代求解基于二部图的最优匹配问题,提出基于Kuhn-Munkres(KM)的模型卸载算法并进一步分析了Fed-MBMO算法的时间复杂度。实验结果表明,在资源与数据极端异质的情况下,该方法能够加速模型收敛,模型训练时间与FedAvg、FedUE和Aergia相比分别平均减少46.65%、12.66%、38.07%。实验结果证明了所提的Fed-MBMO算法能够有效解决“滞后者”效应问题并显著提高联邦学习效率。 展开更多
关键词 联邦学习 滞后者效应 模型卸载 强弱匹配 资源异质性 模型重构 边缘计算
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刑法应对人类基因科技潜在风险的模式选择
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作者 魏汉涛 桑宇 《安徽师范大学学报(社会科学版)》 2025年第1期74-84,共11页
人类基因编辑技术开发与应用潜在的利益与风险均很大,如何平衡科技进步与风险防范是刑法规制这类行为最根本的问题。对此,国外学者提出了自由尊严观下的弱式风险预防与秩序尊严观下的强式风险预防两种观点。前者主张只要风险未被彻底证... 人类基因编辑技术开发与应用潜在的利益与风险均很大,如何平衡科技进步与风险防范是刑法规制这类行为最根本的问题。对此,国外学者提出了自由尊严观下的弱式风险预防与秩序尊严观下的强式风险预防两种观点。前者主张只要风险未被彻底证立,就不应当干预人类基因编辑技术的发展;后者认为只要风险未被彻底证否,就应当禁止冒险。这两种价值取向各有利弊,都不宜总领全局,理性的选择是分域而治。不管哪种预防模式,人类基因编辑行为的刑法规制都要有底线,即应当遵循合目的性原则、社会公平原则、人类基因纯正原则、人权人道原则。现行刑法对人类基因编辑行为的规制,存在缺乏前瞻性、规制范围过窄、犯罪主体单一、预防模式保守等问题,需要根据底线思维和分域而治的方法,区分不同人类基因编辑行为潜在的不同危害,分别采用不同的预防模式。 展开更多
关键词 人类基因编辑 强式风险预防 弱式风险预防 规制模式
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Honeycomb-spiderweb-inspired self-similar hybrid cellular structures for impact applications
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作者 K.Tewari M.K.Pandit +1 位作者 M.M.Mahapatra P.R.Budarapu 《Defence Technology(防务技术)》 2025年第1期182-200,共19页
Inspired by nature's self-similar designs,novel honeycomb-spiderweb based self-similar hybrid cellular structures are proposed here for efficient energy absorption in impact applications.The energy absorption is e... Inspired by nature's self-similar designs,novel honeycomb-spiderweb based self-similar hybrid cellular structures are proposed here for efficient energy absorption in impact applications.The energy absorption is enhanced by optimizing the geometry and topology for a given mass.The proposed hybrid cellular structure is arrived after a thorough analysis of topologically enhanced self-similar structures.The optimized cell designs are rigorously tested considering dynamic loads involving crush and high-velocity bullet impact.Furthermore,the influence of thickness,radial connectivity,and order of patterning at the unit cell level are also investigated.The maximum crushing efficiency attained is found to be more than 95%,which is significantly higher than most existing traditional designs.Later on,the first and second-order hierarchical self-similar unit cell designs developed during crush analysis are used to prepare the cores for sandwich structures.Impact tests are performed on the developed sandwich structures using the standard 9-mm parabellum.The influence of multistaging on impact resistance is also investigated by maintaining a constant total thickness and mass of the sandwich structure.Moreover,in order to avoid layer-wise weak zones and hence,attain a uniform out-of-plane impact strength,off-setting the designs in each stage is proposed.The sandwich structures with first and second-order self-similar hybrid cores are observed to withstand impact velocities as high as 170 m/s and 270 m/s,respectively. 展开更多
关键词 Sandwich structures Honeycomb-spider web inspired Self-similar hierarchy Crush analysis High-velocity impact strong and weak zones Multistaging
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Weak harmonic signal detection method in chaotic interference based on extended Kalman filter 被引量:9
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作者 Chengye Lu Sheng Wu +1 位作者 Chunxiao Jiang Jinfeng Hu 《Digital Communications and Networks》 SCIE 2019年第1期51-55,共5页
The traditional methods of weak harmonic signal detection under strong chaotic interference often suffer from high computational complexity and poor performance. In this paper, an Extended Kalman Filter (EKF) based de... The traditional methods of weak harmonic signal detection under strong chaotic interference often suffer from high computational complexity and poor performance. In this paper, an Extended Kalman Filter (EKF) based detection method is proposed for the detection of weak harmonic signal. The EKF method avoids matrix inversion by iterating measurement equation and state equation, which simultaneously improves the robustness and reduces the complexity. Compared with the existing detection methods, the proposed method has the following advantages: 1) it has better performance than the neural network method;2) it has similar performance with the optimal filtering method, but with lower computational complexity;3) it is more robust compared with the optimal filtering method. 展开更多
关键词 Extended KALMAN filter strong CHAOTIC INTERFERENCE weak HARMONIC signal
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Application of local polynomial estimation in suppressing strong chaotic noise 被引量:3
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作者 Su Li-Yun Ma Yan-Ju Li Jiao-Jun 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第2期181-186,共6页
In this paper, we propose a new method that combines chaotic series phase space reconstruction and local polynomial estimation to solve the problem of suppressing strong chaotic noise. First, chaotic noise time series... In this paper, we propose a new method that combines chaotic series phase space reconstruction and local polynomial estimation to solve the problem of suppressing strong chaotic noise. First, chaotic noise time series are reconstructed to obtain multivariate time series according to Takens delay embedding theorem. Then the chaotic noise is estimated accurately using local polynomial estimation method. After chaotic noise is separated from observation signal, we can get the estimation of the useful signal. This local polynomial estimation method can combine the advantages of local and global law. Finally, it makes the estimation more exactly and we can calculate the formula of mean square error theoretically. The simulation results show that the method is effective for the suppression of strong chaotic noise when the signal to interference ratio is low. 展开更多
关键词 strong chaotic noise local polynomial estimation weak signal detection
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P-kernel Normal Systems in Weakly P-inversive Semigroups 被引量:1
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作者 CHEN Qian-hua FAN Xing-kui 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2008年第2期171-177,共7页
In this paper, we first give the concept of weakly P-inversive semigroup S(P). Then we describe the strong P-congruences on S(P) in terms of their P-kernel normal systems. It is proved that there is a bijection be... In this paper, we first give the concept of weakly P-inversive semigroup S(P). Then we describe the strong P-congruences on S(P) in terms of their P-kernel normal systems. It is proved that there is a bijection between the strong P-congruences and the P-kernel normal systems. Finally, it is also prove that the lattice of strong P-congruences and the lattice of P-kernel normal systems on S(P) are isomorphic. 展开更多
关键词 weakly P-inversive semigroup strong P-congruence P-kernel normal system lattice isomorphism
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Strong Law of Large Numbers under an Upper Probability 被引量:1
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作者 Xiaoyan Chen 《Applied Mathematics》 2012年第12期2056-2062,共7页
Strong law of large numbers is a fundamental theory in probability and statistics. When the measure tool is nonadditive, this law is very different from additive case. In 2010 Chen investigated the strong law of large... Strong law of large numbers is a fundamental theory in probability and statistics. When the measure tool is nonadditive, this law is very different from additive case. In 2010 Chen investigated the strong law of large numbers under upper probabilityVby assumingVis continuous. This assumption is very strong. Upper probabilities may not be continuous. In this paper we prove the strong law of large numbers for an upper probability without the continuity assumption whereby random variables are quasi-continuous and the upper probability is generated by a weakly compact family of probabilities on a complete and separable metric sample space. 展开更多
关键词 strong Law of Large NUMBERS UPPER PROBABILITY weakLY Compact INDEPENDENCE QUASI-CONTINUOUS
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THE FIRST BOUNDARY VALUE PROBLEM FOR STRONGLY DEGENERATE QUASILINEAR PARABOLIC EQUATIONS IN ANISOTROPIC SOBOLEV SPACES 被引量:1
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作者 招燕燕 陈祖墀 《Acta Mathematica Scientia》 SCIE CSCD 2006年第2期255-264,共10页
This article concerns the existence of weak solutions of the first boundary value problem for a kind of strongly degenerate quasilinear parabolic equation in the anisotropic Sobolev Space. With the theory of anisotrop... This article concerns the existence of weak solutions of the first boundary value problem for a kind of strongly degenerate quasilinear parabolic equation in the anisotropic Sobolev Space. With the theory of anisotropic Sobolev spaces an existence result is proved. 展开更多
关键词 weak solution strongly degenerate quasilinear parabolic equation 2000 MR Subject Classification 35K55 35K60 35K65
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CRITERIA OF STRONG TRANSIENCE FOR OPERATOR-SELF-SIMILAR MARKOV PROCESSES
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作者 吴传菊 张峰 刘禄勤 《Acta Mathematica Scientia》 SCIE CSCD 2006年第1期41-48,共8页
Yamamuro in [1] defines strong and weak transience of Markov processes; gives a criterion for strong transience of Feller processes; and further, discusses strong and weak transience of Ornstein-Uhlenbeck type process... Yamamuro in [1] defines strong and weak transience of Markov processes; gives a criterion for strong transience of Feller processes; and further, discusses strong and weak transience of Ornstein-Uhlenbeck type processes. In this article, the authors weaken the Feller property of the result in [1] to weak Feller property and discuss the strong transience of operator-self-similar Markov processes. 展开更多
关键词 Operator-self-similar processes strong transience ISOTROPIC weak Feller processes
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