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An approximate nonlinear modified Mohr-Coulomb shear strength criterion with critical state for intact rocks 被引量:7
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作者 Baotang Shen Jingyu Shi Nick Barton 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2018年第4期645-652,共8页
In this paper, the Mohr-Coulomb shear strength criterion is modified by mobilising the cohesion and internal friction angle with normal stress, in order to capture the nonlinearity and critical state concept for intac... In this paper, the Mohr-Coulomb shear strength criterion is modified by mobilising the cohesion and internal friction angle with normal stress, in order to capture the nonlinearity and critical state concept for intact rocks reported in the literature. The mathematical expression for the strength is the same as the classical form, but the terms of cohesion and internal friction angle depend on the normal stress now,leading to a nonlinear relationship between the strength and normal stress. It covers both the tension and compression regions with different expressions for cohesion and internal friction angle. The strengths from the two regions join continuously at the transition of zero normal stress. The part in the compression region approximately satisfies the conditions of critical state, where the maximum shear strength is reached. Due to the nonlinearity, the classical simple relationship between the parameters of cohesion, internal friction angle and uniaxial compressive strength from the linear Mohr-Coulomb criterion does not hold anymore. The equation for determining one of the three parameters in terms of the other two is supplied. This equation is nonlinear and thus a nonlinear equation solver is needed. For simplicity, the classical linear relationship is used as a local approximation. The approximate modified Mohr-Coulomb criterion has been implemented in a fracture mechanics based numerical code FRACOD,and an example case of deep tunnel failure is presented to demonstrate the difference between the original and modified Mohr-Coulomb criteria. It is shown that the nonlinear modified Mohr-Coulomb criterion predicts somewhat deeper and more intensive fracturing regions in the surrounding rock mass than the original linear Mohr-Coulomb criterion. A more comprehensive piecewise nonlinear shear strength criterion is also included in Appendix B for those readers who are interested. It covers the tensile, compressive, brittle-ductile behaviour transition and the critical state, and gives smooth transitions. 展开更多
关键词 Shear strength Modified mohr-coulomb criterion Critical state Intact rock
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Upper bound analysis of ultimate pullout capacity of shallow 3-D circular plate anchors based on nonlinear Mohr-Coulomb failure criterion 被引量:7
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作者 ZHAO Lian-heng TAN Yi-gao +2 位作者 HU Shi-hong DENG Dong-ping YANG Xin-ping 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第9期2272-2288,共17页
Based on the nonlinear Mohr-Coulomb failure criterion and the associated flow rules,the three-dimensional(3-D)axisymmetric failure mechanism of shallow horizontal circular plate anchors that are subjected to the ultim... Based on the nonlinear Mohr-Coulomb failure criterion and the associated flow rules,the three-dimensional(3-D)axisymmetric failure mechanism of shallow horizontal circular plate anchors that are subjected to the ultimate pullout capacity(UPC)is determined.A derivative function of the projection function for projecting the 3-D axisymmetric failure surface on plane is deduced using the variation theory.By using difference principle,the primitive function of failure surface satisfying boundary condition and numerical solution to its corresponding ultimate pullout capacity function are obtained.The influences of nonlinear Mohr-Coulomb parameters on UPC and failure mechanism are studied.The result shows that UPC decreases with dimensionless parameter m and uniaxial tensile strength increases but increases when depth and radius of plate anchor,surface overload,initial cohesion,geomaterial density and friction angle increase.The failure surface is similar to a symmetrical spatial funnel,and its shape is mainly determined by dimensionless parameter m;the surface damage range expands with the increase of radius and depth of the plate anchor as well as initial cohesion but decreases with the increase of dimensionless parameter m and uniaxial tensile strength as well as geomaterial density.As the dimensionless parameter m=2.0,the numerical solution of UPC based on the difference principle is proved to be feasible and effective through the comparison with the exact solution.In addition,the comparison between solutions of UPC computed by variation method and those computed by upper bound method indicate that variation method outperforms upper bound method. 展开更多
关键词 shallow circular plate anchors ultimate pullout capacity variation analysis nonlinear mohr-coulomb failure criterion upper bound limit analysis
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Formation mechanism and criterion of linear segregation in ZL205A alloy 被引量:10
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作者 王晔 吴士平 +3 位作者 薛祥 陈瑞润 张建兵 肖文峰 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第11期3632-3638,共7页
The experiments and numerical simulation were conducted for ZL205A aluminum alloy cylindrical shell casting. The formation mechanism of the linear segregation produced by the low pressure die casting (LPDC) process wa... The experiments and numerical simulation were conducted for ZL205A aluminum alloy cylindrical shell casting. The formation mechanism of the linear segregation produced by the low pressure die casting (LPDC) process was investigated. And the heat transfer of the casting during solidification process was analyzed by simulation technique, resulting from the information of linear segregation obtained by plenty of experiments. The new linear segregation criterion was proposed through the simulation and experimental results. It was found that the melting metal with high Cu contents was feeding the crack shrinkage formed by the tearing under the effect of feeding pressure during the later solidification, which led to the formation of linear segregation. The control methods for the linear segregation were suggested based on the proposed mechanism. Finally, the criterion of linear segregation was confirmed by the production of the actual castings. 展开更多
关键词 cylindrical shell casting linear segregation formation mechanism criterion control method
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Modified Mohr-Coulomb strength criterion considering rock mass intrinsic material strength factorization 被引量:6
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作者 ZHANG Qiang,WANG Shuilin,GE Xiurun,WANG Hongying State Key Laboratory of Geomechanics and Geotechnical Engineering,Institute of Rock and Soil Mechanics,Chinese Academy of Sciences,Wuhan 430071,China 《Mining Science and Technology》 EI CAS 2010年第5期701-706,共6页
With the increase of mining depth of mineral resources,the rock mass stress state is being more and more complex.The rock mass show different features,namely,with the increase of hydrostatic pressure,rock mass failure... With the increase of mining depth of mineral resources,the rock mass stress state is being more and more complex.The rock mass show different features,namely,with the increase of hydrostatic pressure,rock mass failure mode turns from brittle tension failure to structure ductile failure and its limit strength also increases.The restriction of minimal principal stress on the initiation and development of microcrack and the change of micro-unit stress state by the intermediate principal stress play a decisive role in the increase of rock mass limit strength.Based on the rock mass failure behavior law under complex stress state and the σ2-dependence on the rock mass strength,we proposed a Modified Mohr-Coulomb(M-MC) strength criterion which is smooth and convex.Finally,the M-MC criterion is validated by multiaxial test data of eight kinds of rock mass.We also compared the fitting results with Mohr-Coulomb criterion(MC).It shows that the new criterion fits the test data better than the Mohr-Coulomb criterion.So the M-MC strength criterion well reveals the rock mass bearing behavior and can be widely used in the rock mass strength analysis.The results can provide theoretical foundations for stability analysis and reinforcement design of complex underground engineering. 展开更多
关键词 rock mass strength criterion mohr-coulomb criterion multiaxial test failure mode underground engineering
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Determination of rock resistant coefficient based on Mohr-Coulomb criterion for underwater tunnel 被引量:5
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作者 Zhong-ren TU Qiang YANG +1 位作者 Qi-ming SHEN Xiao-wen WANG 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2008年第9期1239-1244,共6页
According to the load-structure method, the wall rock with lining can bear the load caused by the surrounding rock, and the rock resistant coefficient (RRC) is a key parameter for evaluating the capacity of this wall ... According to the load-structure method, the wall rock with lining can bear the load caused by the surrounding rock, and the rock resistant coefficient (RRC) is a key parameter for evaluating the capacity of this wall rock. Based on the Mohr-Coulomb yield criterion, this paper develops a formula for calculating the RRC, which has been applied to the real engi-neering project, such as Xiamen Xiang’an East Passage Underwater Tunnel Project. The fact shows that this formula is helpful for designers to determine the RRC value. 展开更多
关键词 Rock resistant coefficient (RRC) mohr-coulomb yield criterion Rock mechanics Underwater tunnel
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Stability Criterion with Less LMI Variables for Linear Discrete-time Systems with Additive Time-delays 被引量:3
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作者 K. Ramakrishnan G. Ray 《International Journal of Automation and computing》 EI 2011年第4期490-492,共3页
In this correspondence paper, an equivalent stability criterion with minimal number of linear matrix inequality (LMI) variables is presented for a delay-dependent stability criterion reported recently in the Interna... In this correspondence paper, an equivalent stability criterion with minimal number of linear matrix inequality (LMI) variables is presented for a delay-dependent stability criterion reported recently in the International Journal of Automation and Computing for a class of linear discrete-time systems with additive time delays. The reported stability criterion for the additive timedelay systems has more number of matrix variables in the LMI and, hence, demand additional computational burden. The proposed equivalent stability criterion, unlike the reported one, does not involve free-weighing matrices and encompass only the matrix variables that are associated in the Lyapunov-Krasovskii functional, making the criterion mathematically less complex and computationally more effective. 展开更多
关键词 Discrete-time systems additive time-delays delay-dependent stability stability criterion linear matrix inequality (LMI).
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Theoretical verification of the rationality of strain energy storage index as rockburst criterion based on linear energy storage law 被引量:9
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作者 Fengqiang Gong Song Luo +1 位作者 Quan Jiang Lei Xu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2022年第6期1737-1746,共10页
The rationality of using strain energy storage index(Wet)for evaluating rockburst proneness was theoretically verified based on linear energy storage(LES)law in this study.The LES law is defined as the linear relation... The rationality of using strain energy storage index(Wet)for evaluating rockburst proneness was theoretically verified based on linear energy storage(LES)law in this study.The LES law is defined as the linear relationship between the elastic strain energy stored inside the solid material and the input strain energy during loading.It is used to determine the elastic strain energy and dissipated strain energy of rock specimens at various loading/unloading stress levels.The results showed that the Wetvalue obtained from experiments was close to the corresponding theoretical one from the LES law.Furthermore,with an increase in the loading/unloading stress level,the ratio of elastic strain energy to dissipated strain energy converged to the peak-strength strain energy storage index(Wp et).This index is stable and can better reflect the relative magnitudes of the stored energy and the dissipated energy of rocks at the whole pre-peak stage than the strain energy storage index.The peak-strength strain energy storage index can replace the conventional strain energy storage index as a new index for evaluating rockburst proneness. 展开更多
关键词 Rockburst criterion Strain energy storage index linear energy storage(LES)law Peak-strength strain energy storage index
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Cracking Patterns of Shear Walls in Reinforced Concrete Structure due to Strong Earthquake Based on Mohr-Coulomb Criterion 被引量:2
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作者 查支祥 刘西拉 +1 位作者 彭卫 许波 《Journal of Donghua University(English Edition)》 EI CAS 2015年第4期541-548,共8页
A primary goal of seismic design of buildings is to protect people's life safety during strong earthquakes. Fundamentally,to predict the survived space and estimate people escape intervals during structural collap... A primary goal of seismic design of buildings is to protect people's life safety during strong earthquakes. Fundamentally,to predict the survived space and estimate people escape intervals during structural collapse are very important,which requires to describe the failure process more detailedly not only for structural joints but also for slabs and shear walls. In the present paper,the details of Mohr-Coulomb failure criterion with tension-cutoff together with its expression in failure surface and local coordinate system of reinforced concrete( RC) shear wall are given firstly,and then several typical cracking patterns of RC shear wall,such as tension shear crack and compression shear crack, are analyzed based on Mohr-Coulomb failure criterion with tension-cutoff. 展开更多
关键词 cracking patterns mohr-coulomb criterion shear wall
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A Linearized and Unified Yield Criterion of Metals and Its Application
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作者 熊慧而 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1994年第5期485-489,共5页
In this paper a linearized and unified yield crierion of metals is presented, which is in a form of a set of linear functions with two pararneters. The parameters are ex- pressed in terms of tension yield stress and ... In this paper a linearized and unified yield crierion of metals is presented, which is in a form of a set of linear functions with two pararneters. The parameters are ex- pressed in terms of tension yield stress and so-called “shear-stretch ratio” and can bereadily determined from experimental data. It is shown that in stress space the set of yield functions is a set of polygons with twelve edges located between the Tresca’s hexagon and twin-shear-stress hexagon ̄[1]. In this paper the present yield function isused to analyse the prestressiap loose running fit cylinders. 展开更多
关键词 ratio of shear-stretch yield criterion linearized and unified form
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基于非线性Mohr-Coulomb强度准则下的扩孔问题解析 被引量:14
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作者 邹金锋 彭建国 +2 位作者 张进华 罗恒 安爱军 《土木工程学报》 EI CSCD 北大核心 2009年第7期90-97,共8页
将圆孔周围的围岩分为弹性和塑性应力区,考虑土体受力后的剪胀特性,根据Mohr-Coulomb非线性强度准则、应力平衡条件、大小变形理论和非关联流动准则,推导出排水情况下土体发生大、小变形时扩孔问题的塑性区应力、应变和位移场解析,并给... 将圆孔周围的围岩分为弹性和塑性应力区,考虑土体受力后的剪胀特性,根据Mohr-Coulomb非线性强度准则、应力平衡条件、大小变形理论和非关联流动准则,推导出排水情况下土体发生大、小变形时扩孔问题的塑性区应力、应变和位移场解析,并给出大、小变形情况下塑性区半径和极限扩孔压力的非线性解答。与现有理论的计算结果和现场实测结果进行对比结果表明,上述理论具有一定的有效性。通过分析可知,大变形时的塑性应变比小变形时的大;随着m值的增大,扩孔压力逐渐增大且与rp/au为非线性关系;大变形时的扩孔压力要比Vesic等人的理论值偏小。 展开更多
关键词 剪胀 非线性Mohr—Coulomb强度准则 扩孔压力 塑性区半径 大变形 非关联流动准则
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Selection of the Linear Regression Model According to the Parameter Estimation 被引量:31
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作者 Sun Dao-de Department of Computer, Fuyang Teachers College, Anhui 236032,China 《Wuhan University Journal of Natural Sciences》 EI CAS 2000年第4期400-405,共6页
In this paper, based on the theory of parameter estimation, we give a selection method and, in a sense of a good character of the parameter estimation, we think that it is very reasonable. Moreover, we offer a calcula... In this paper, based on the theory of parameter estimation, we give a selection method and, in a sense of a good character of the parameter estimation, we think that it is very reasonable. Moreover, we offer a calculation method of selection statistic and an applied example. 展开更多
关键词 parameter estimation linear regression model selection criterion mean square error
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Derivation of Plastic Work Rate Done per Unit Volume for Mean Yield Criterion and Its Application 被引量:8
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作者 Dewen ZHAO Yingjie XIE +1 位作者 Xiaowen WANG Xianghua LIU 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2005年第4期433-436,共4页
In Haigh Westergaard stress space linear combination of twin shear stress and Tresca yield functions is called the mean yield (MY) criterion. The mathematical relationship of the criterion and its plastic work rate ... In Haigh Westergaard stress space linear combination of twin shear stress and Tresca yield functions is called the mean yield (MY) criterion. The mathematical relationship of the criterion and its plastic work rate done per unit volume were derived. A generalized worked example of slab forging was analyzed by the criterion and its corresponding plastic work rate done per unit volume. Then, the precision of the solution was compared with those by Mises and Twin shear stress yield criterions, respectively. It turned out that the calculated results by MY criterion were in good agreement with those by Mises criterion. 展开更多
关键词 Mean yield criterion Plastic work rate done per unit volume Functional linearization Slab forging
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Limit equilibrium analysis for rock slope stability using basic Hoek–Brown strength criterion 被引量:6
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作者 邓东平 赵炼恒 李亮 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第9期2154-2163,共10页
Hoek–Brown(HB)strength criterion can reflect rock’s inherent failure nature,so it is more suitable for analyzing the stability of rock slopes.However,the traditional limit equilibrium methods are at present only sui... Hoek–Brown(HB)strength criterion can reflect rock’s inherent failure nature,so it is more suitable for analyzing the stability of rock slopes.However,the traditional limit equilibrium methods are at present only suitable for analyzing the rock slope stability using the linear equivalent Mohr–Coulomb(EMC)strength parameters instead of the nonlinear HB strength criterion.Therefore,a new method derived to analyze directly the rock slope stability using the nonlinear HB strength criterion for arbitrary curve slip surface was described in the limit equilibrium framework.The current method was established based on certain assumptions concerning the stresses on the slip surface through amending the initial normal stressσ0 obtained without considering the effect of inter-slice forces,and it can satisfy all static equilibrium conditions of the sliding body,so the current method can obtain the reasonable and strict factor of safety(FOS)solutions.Compared with the results of other methods in some examples,the feasibility of the current method was verified.Meanwhile,the parametric analysis shows that the slope angleβhas an important influence on the difference of the results obtained using the nonlinear HB strength criterion and its linear EMC strength parameters.Forβ≤45°,both of the results are similar,showing the traditional limit equilibrium methods using the linear EMC strength parameters and the current method are all suitable to analyze rock slope stability,but forβ>60°,the differences of both the results are obvious,showing the actual slope stability state can not be reflected in the traditional limit equilibrium methods,and then the current method should be used. 展开更多
关键词 Hoek-Brown strength criterion linear equivalent mohr-coulomb strength parameters slope stability limit equilibrium slip surface factor of safety
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Triaxial strength behaviour of rockmass satisfying Modified Mohr-Coulomb and Generalized Hoek-Brown criteria 被引量:5
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作者 Saurav Rukhaiyar Narendra Kumar Samadhiya 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2018年第6期901-915,共15页
The triaxial strength of twenty rockmass types was predicted using two non-linear triaxial strength criteria for rockmass i.e. Modified Mohr-Coulomb(MMC) criterion and Generalized Hoek-Brown(GHB)criterion. Four differ... The triaxial strength of twenty rockmass types was predicted using two non-linear triaxial strength criteria for rockmass i.e. Modified Mohr-Coulomb(MMC) criterion and Generalized Hoek-Brown(GHB)criterion. Four different rockmass classification systems were used for the calculation of MMC criterion parameters while only GSI classification system has been used for calculation of GHB parameters. The representative value of the uniaxial compressive strength and elastic modulus of rockmass have been estimated using probabilistic approach. A hypothetical case of an unsupported tunnel has been analyzed considering both MMC and GHB criteria. The analysis was done using the convergence-confinement method with two different approaches. The first approach predicts the tunnel response using GHB criterion directly. The second approach predicts the tunnel response using equivalent Mohr-Coulomb parameters obtained by linearization of triaxial data points obtained from MMC and GHB criteria. The tunnel response has been estimated in terms of radius of plastic zone, tunnel convergence and tunnel convergence strain. For very poor rockmasses the tunnel response predicted by MMC criterion is less than that predicted by GHB criterion. For poor and fair rockmass, the tunnel response estimated considering both the criteria are comparable except for few cases. Squeezing condition in rockmass has been also evaluated. 展开更多
关键词 TRIAXIAL STRENGTH MODIFIED mohr-coulomb criterion Generalised HOEK-BROWN criterion Convergence-confinement method
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Validation of Hoek-Brown failure criterion charts for rock slopes 被引量:2
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作者 A.M.Nekouei K.Ahangari 《International Journal of Mining Science and Technology》 SCIE EI 2013年第6期805-808,共4页
Although stability charts suggested by Hoek and Bray on the basis of Mohr-Coulomb criterion are used for rock slopes,but complete and precise recognition is required for distinguishing cohesive strength and Mohr-Coulo... Although stability charts suggested by Hoek and Bray on the basis of Mohr-Coulomb criterion are used for rock slopes,but complete and precise recognition is required for distinguishing cohesive strength and Mohr-Coulomb equivalent internal friction angle for rock mass.The paper by Lia et al.[6]is the only one that introduced rock slope charts according to Hoek-Brown failure criterion.In this paper,at first,this type of charts is introduced.Then,Mohr-Coulomb failure criterion charts[2]are compared and validated with Hoek-Brown failure criterion ones[6].Next,Bishop method utilizing Slide software is compared with Hoek-Brown failure criterion stability charts.Average standard deviation(ASD),root mean square error(RMSE)and variance account for(VAF)were used for the comparison.According to the results,because of high distribution and very low correlation among the comparisons,Hoek-Brown failure criterion charts are not efficient. 展开更多
关键词 Slope stability Stability charts mohr-coulomb failure criterion Hoek-Brown failure criterion
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The improved local linear prediction of chaotic time series 被引量:2
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作者 孟庆芳 彭玉华 孙佳 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第11期3220-3225,共6页
Based on the Bayesian information criterion, this paper proposes the improved local linear prediction method to predict chaotic time series. This method uses spatial correlation and temporal correlation simultaneously... Based on the Bayesian information criterion, this paper proposes the improved local linear prediction method to predict chaotic time series. This method uses spatial correlation and temporal correlation simultaneously. Simulation results show that the improved local linear prediction method can effectively make multi-step and one-step prediction of chaotic time series and the multi-step prediction performance and one-step prediction accuracy of the improved local linear prediction method are superior to those of the traditional local linear prediction method. 展开更多
关键词 local linear prediction Bayesian information criterion state space reconstruction chaotic time series
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CONSENSUS ANALYSIS AND DESIGN OF LINEAR INTERCONNECTED MULTI-AGENT SYSTEMS 被引量:1
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作者 陈阳舟 李伟 +1 位作者 代桂平 A.Yu.ALEKSANDROV 《Acta Mathematica Scientia》 SCIE CSCD 2015年第6期1305-1317,共13页
We deal with the state consensus problem of a general Linear Interconnected Multi-Agent System (LIMAS) under a time-invariant and directed communication topology. Firstly, we propose a linear consensus protocol in a... We deal with the state consensus problem of a general Linear Interconnected Multi-Agent System (LIMAS) under a time-invariant and directed communication topology. Firstly, we propose a linear consensus protocol in a general form, which consists of state feedback of the agent itself and feedback form of the relative states between the agent and its neighbors. Secondly, a state-linear-transformation is applied to equivalently transform the state consensus problem into a partial stability problem. Based on the partial stability theory, we derive a sufficient and necessary criterion of consensus convergence, which is expressed via the Hurwitz stability of a real matrix constructed from the parameters of the agent models and the protocols, and present an analytical formula of the consensus function. Lastly, we propose a design procedure of the gain matrices in the protocol by solving a bilinear matrix inequality. 展开更多
关键词 linear interconnected multi-agent system (LIMAS) partial stability state-linear-transformation criterion of consensus convergence consensus design
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Two-dimensional face stability analysis in rock masses governed by the Hoek-Brown strength criterion with a new multi-horn mechanism 被引量:2
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作者 Junhao Zhong Xiaoli Yang 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2023年第8期963-976,共14页
The face stability problem is a major concern for tunnels excavated in rock masses governed by the Hoek-Brown strength criterion.To provide an accurate prediction for the theoretical solution of the critical face pres... The face stability problem is a major concern for tunnels excavated in rock masses governed by the Hoek-Brown strength criterion.To provide an accurate prediction for the theoretical solution of the critical face pressure,this study adopts the piecewise linear method(PLM)to account for the nonlinearity of the strength envelope and proposes a new multi-horn rotational mechanism based on the Hoek-Brown strength criterion and the associative flow rule.The analytical solution of critical support pressure is derived from the energy-work balance equation in the framework of the plastic limit theorem;it is formulated as a multivariable nonlinear optimization problem relying on 2m dependent variables(m is the number of segments).Meanwhile,two classic linearized measures,the generalized tangential technique(GTT)and equivalent Mohr-Coulomb parameters method(EMM),are incorporated into the analysis for comparison.Surprisingly,the parametric study indicates a significant improvement in support pressure by up to 13%compared with the GTT,and as expected,the stability of the tunnel face is greatly influenced by the rock strength parameters.The stress distribution on the rupture surface is calculated to gain an intuitive understanding of the failure at the limit state.Although the limit analysis is incapable of calculating the true stress distribution in rock masses,a rough approximation of the stress vector on the rupture surface is permitted.In the end,sets of normalized face pressure are provided in the form of charts for a quick assessment of face stability in rock masses. 展开更多
关键词 Face stability Piecewise linear method Hoek-Brown strength criterion Multi-horn rotational mechanism Limit analysis
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Delay-dependent robust stabilization for a class ofneutral systems with nonlinear perturbations 被引量:1
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作者 Ming LI Guangda HU 《控制理论与应用(英文版)》 EI 2007年第4期409-414,共6页
This note deals with the problem of stabilization/stability for neutral systems with nonlinear perturbations. A new stabilization/stability scheme is presented. Using improved Lyapunov functionals, less conservative s... This note deals with the problem of stabilization/stability for neutral systems with nonlinear perturbations. A new stabilization/stability scheme is presented. Using improved Lyapunov functionals, less conservative stabilization/stability conditions are derived for such systems based on linear matrix inequalities (LMI). Numerical examples are provided to show that the proposed results significantly improve the allowed upper bounds of the delay size over some existing ones in the literature. 展开更多
关键词 Delay-dependent criterion Robust stabilization/stability linear matrix inequality (LMI) Neutral delaysystems State feedback stabilization Nonlinear perturbations
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An osculatory rational interpolation method of model reduction in linear system 被引量:1
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作者 顾传青 张莺 《Journal of Shanghai University(English Edition)》 CAS 2007年第4期365-369,共5页
A theorem for osculatory rational interpolation was shown to establish a new criterion of interpolation. On the basis of this conclusion a practical algorithm was presented to get a reduction model of the linear syste... A theorem for osculatory rational interpolation was shown to establish a new criterion of interpolation. On the basis of this conclusion a practical algorithm was presented to get a reduction model of the linear systems. Some numerical examples were given to explain the result in this paper. 展开更多
关键词 osculatory rational interpolation criterion of interpolation ALGORITHM linear system model reduction
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