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Level density of odd-A nuclei at saddle point
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作者 Wei Zhang Wei Gao +1 位作者 Gui-Tao Zhang Zhi-Yuan Li 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第8期164-173,共10页
Based on the covariant density functional theory,by employing the core–quasiparticle coupling(CQC)model,the nuclear level density of odd-A nuclei at the saddle point is achieved.The total level density is calculated ... Based on the covariant density functional theory,by employing the core–quasiparticle coupling(CQC)model,the nuclear level density of odd-A nuclei at the saddle point is achieved.The total level density is calculated via the convolution of the intrinsic level density and the collective level density.The intrinsic level densities are obtained in the finite-temperature covariant density functional theory,which takes into account the nuclear deformation and pairing self-consistently.For saddle points on the free energy surface in the(β_(2),γ)plane,the entropy and the associated intrinsic level density are compared with those of the global minima.By introducing a quasiparticle to the two neighboring even–even core nuclei,whose properties are determined by the five-dimensional collective Hamiltonian model,the collective levels of the odd-A nuclei are obtained via the CQC model.The total level densities of the^(234-240)U agree well with the available experimental data and Hilaire’s result.Furthermore,the ratio of the total level densities at the saddle points to those at the global minima and the ratio of the total level densities to the intrinsic level densities are discussed separately. 展开更多
关键词 Level density Covariant density functional theory Core–quasiparticle coupling model saddle point
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Saddle-Dolomite-Bearing Fracture Fillings and Records of Hot Brine Activity in the Jialingjiang Formation,Libixia Section,Hechuan Area of Chongqing City 被引量:2
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作者 HUANG Keke ZHONG Yijiang +2 位作者 HUANG Sijing LI Xiaoning FENG Mingshi 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第1期195-208,共14页
Most vein minerals deposited in fractures of the Jialingjiang Formation from Libixia section, Hechan area include a large amount of saddle dolomite and accompanying celestite, calcite and fluorite. This study analyzed... Most vein minerals deposited in fractures of the Jialingjiang Formation from Libixia section, Hechan area include a large amount of saddle dolomite and accompanying celestite, calcite and fluorite. This study analyzed the nature, source, evolution of the fluids by plane-light petrography, fluid-inclusion methods, cathodoluminescence images, and stable isotopic compositions. The homogenization temperatures of two-phase aqueous fluid inclusions in dolomite range between 100 and 270℃. Combined with the jlSO data, it is suggested that the fluid responsible for the precipitation of fracture fillings have δ18O values between 10%o and 18‰ (relative to SMOW). The saddle dolomite and the accompanying minerals were the result of activity of dense brines at elevated temperatures. Moreover, analysis shows that the fluid was derived from a mixture of marine-derived brine and deeper circulating flow. This fluid was enriched in Sr during diagenesis and formed celestite in fracture and for regional mineralization. Dissolution of saddle dolomite was attributed to the cooling of Mg/Ca-decreased fluids, which may relate to a leaching of gypsum to celestite in surrounding carbonates. 展开更多
关键词 Libixia section Jialingjiang Formation saddle dolomite hot brine Hechuan area CHONGQING
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Dynamic modeling and parameter identification of a gun saddle ring 被引量:4
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作者 Tong Lin Lin-fang Qian +2 位作者 Qiang Yin Shi-yu Chen Tai-su Liu 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2020年第2期325-333,共9页
In this study,a theoretical nonlinear dynamic model was established for a saddle ring based on a dynamic force analysis of the launching process and the structure according to contact-impact theory.The ADAMS software ... In this study,a theoretical nonlinear dynamic model was established for a saddle ring based on a dynamic force analysis of the launching process and the structure according to contact-impact theory.The ADAMS software was used to build a parameterized dynamic model of the saddle ring.A parameter identification method for the ring was proposed based on the particle swarm optimization algorithm.A loading test was designed and performed several times at different elevation angles.The response histories of the saddle ring with different loads were then obtained.The parameters of the saddle ring dynamic model were identified from statistics generated at a 500 elevation angle to verify the feasibility and accuracy of the proposed method.The actual loading history of the ring at a 70°elevation angle was taken as the model input.The response histories of the ring under these working conditions were obtained through a simulation.The simulation results agreed with the actual response.Thus,the effectiveness and applicability of the proposed dynamic model were verified,and it provides an effective method for modeling saddle rings. 展开更多
关键词 GUN saddle RING DYNAMIC response PARAMETER identification Particle SWARM optimization
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Coherence-Resonance-Induced Neuronal Firing near a Saddle-Node and Homoclinic Bifurcation Corresponding to Type-I Excitability 被引量:3
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作者 贾冰 古华光 李玉叶 《Chinese Physics Letters》 SCIE CAS CSCD 2011年第9期62-65,共4页
Excitability is an essential characteristic of excitable media such as nervous and cardiac systems.Different types of neuronal excitability are related to different bifurcation structures.We simulate the coherence res... Excitability is an essential characteristic of excitable media such as nervous and cardiac systems.Different types of neuronal excitability are related to different bifurcation structures.We simulate the coherence resonance effect near a saddle-node and homoclinic bifurcation corresponding to type-I excitability in a theoretical neuron model,and recognize the obvious features of the corresponding firing pattern.Similar firing patterns are discovered in rat hippocampal CA1 pyramidal neurons.The results are not only helpful for understanding the dynamics of the saddle-node bifurcation and type-I excitability in a realistic nervous system,but also provide a practical indicator to identify types of excitability and bifurcation. 展开更多
关键词 BIFURCATION BIFURCATION saddle
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Coincidence Point Theorems,Intersection Theorems and Saddle Point Theorems on FC-spaces 被引量:1
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作者 PIAO YONG-JIE YIN ZHE 《Communications in Mathematical Research》 CSCD 2009年第2期115-122,共8页
In this paper, we first give the definitions of finitely continuous topological space and FC-subspace generated by some set, and obtain coincidence point theorem, whole intersection theorems and Ky Fan type matching t... In this paper, we first give the definitions of finitely continuous topological space and FC-subspace generated by some set, and obtain coincidence point theorem, whole intersection theorems and Ky Fan type matching theorems, and finally discuss the existence of saddle point as an application of coincidence point theorem. 展开更多
关键词 FC-SPACE FC-subspace generated by set saddle point
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The Formula of Generalized Center-Weak Saddle 被引量:1
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作者 万维明 迟晓恒 《Northeastern Mathematical Journal》 CSCD 2002年第1期89-94,共6页
In this paper, a problem of center-weak focus of a general system of degree n is transformed into a problem of generalized center-weak saddle. It offers: (1) the calculating formula of the saddle values of the former ... In this paper, a problem of center-weak focus of a general system of degree n is transformed into a problem of generalized center-weak saddle. It offers: (1) the calculating formula of the saddle values of the former 4 orders in the general system of degree three; (2) some calculating formulae of the saddle values in the general homogeneous system of degree n.The problem of center-focus(saddle) plays an important role in the qualitative theory of ordinary differential equations. However, since the calculations are difficult, the results have not been satisfactory. On the basis of the author's work, Northeast. Math. J., 13(4)(1997), 487-494, the paper offers some calculating formulae of the saddle values. 展开更多
关键词 CENTER FOCUS saddle Homogeneous system.
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Convergence analysis of the corrected Uzawa algorithm for symmetric saddle point problems 被引量:2
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作者 LU Jun-feng 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2014年第1期29-35,共7页
For the large sparse saddle point problems, Pan and Li recently proposed in [H. K. Pan, W. Li, Math. Numer. Sinica, 2009, 31(3): 231-242] a corrected Uzawa algorithm based on a nonlinear Uzawa algorithm with two no... For the large sparse saddle point problems, Pan and Li recently proposed in [H. K. Pan, W. Li, Math. Numer. Sinica, 2009, 31(3): 231-242] a corrected Uzawa algorithm based on a nonlinear Uzawa algorithm with two nonlinear approximate inverses, and gave the detailed convergence analysis. In this paper, we focus on the convergence analysis of this corrected Uzawa algorithm, some inaccuracies in [H. K. Pan, W. Li, Math. Numer. Sinica, 2009, 31(3): 231-242] are pointed out, and a corrected convergence theorem is presented. A special case of this modified Uzawa algorithm is also discussed. 展开更多
关键词 saddle point problem Uzawa algorithm convergence analysis
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Mixed Saddle Point and Its Equivalence with an Efficient Solution under Generalized (V, <i>p</i>)-Invexity 被引量:1
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作者 Arvind Kumar Pankaj Kumar Garg 《Applied Mathematics》 2015年第9期1630-1637,共8页
The purpose of this paper is to define the concept of mixed saddle point for a vector-valued Lagrangian of the non-smooth multiobjective vector-valued constrained optimization problem and establish the equivalence of ... The purpose of this paper is to define the concept of mixed saddle point for a vector-valued Lagrangian of the non-smooth multiobjective vector-valued constrained optimization problem and establish the equivalence of the mixed saddle point and an efficient solution under generalized (V, p)-invexity assumptions. 展开更多
关键词 Nonsmooth Multiobjective Programs (V p)-Invexity MIXED saddle Point Vector-Valued MIXED Lagrangian Function
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Kinematic Geometry for the Saddle Line Fitting of Planar Discrete Positions 被引量:1
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作者 WU Yu WANG Delun +2 位作者 WANG Wei YU Shudong XU Wenji 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2015年第4期763-768,共6页
The position synthesis of planar linkages is to locate the center point of the moving joint on a rigid link, whose trajectory is a circle or a straight line. Utilizing the min-max optimization scheme, the fitting curv... The position synthesis of planar linkages is to locate the center point of the moving joint on a rigid link, whose trajectory is a circle or a straight line. Utilizing the min-max optimization scheme, the fitting curve needs to minimize the maximum fitting error to acquire the dimension of a planar binary P-R link. Based on the saddle point programming, the fitting straight line is determined to the planar discrete point-path traced by the point of the rigid body in planar motion. The property and evolution of the defined saddle line error can be revealed from three given separate points. A quartic algebraic equation relating the fitting error and the coordinates is derived, which agrees with the classical theory. The effect of the fourth point is discussed in three cases through the constraint equations. The multi-position saddle line error is obtained by combination and comparison from the saddle point programming. Several examples are presented to illustrate the solution process for the saddle line error of the moving plane. The saddle line error surface and the contour map presented to show the variations of the fitting error in the fixed frame. The discrete kinematic geometry is then set up to disclose the relations of the separate positions of the rigid body, the location of the tracing point on the moving body, and the position and orientation of the saddle line to the point-path. This paper presents a new analytic geometry method for saddle line fitting and provides a theoretical foundation for position synthesis. 展开更多
关键词 saddle point programming kinematic geometry saddle line error position synthesis
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An Effective Numerical Procedure to Determine Saddle-Type Unstable Invariant Limit Sets in Nonlinear Systems 被引量:1
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作者 江俊 《Chinese Physics Letters》 SCIE CAS CSCD 2012年第5期52-55,共4页
A new technique that can efficiently approximate the attracting set of a nonlinear dynamical system is proposed under the framework of point mapping with the cell reference method.With the aid of the approximated attr... A new technique that can efficiently approximate the attracting set of a nonlinear dynamical system is proposed under the framework of point mapping with the cell reference method.With the aid of the approximated attracting set,the difficulties encountered by the PIM-triple method and bisection procedure in finding trajectories on the stable manifolds of chaotic saddles in basins of attraction and on basin boundaries can be overcome well.On the basis of this development,an effective method to determine saddle-type invariant limit sets of nonlinear dynamical systems can be devised.Examples are presented for the purposes of illustration and to demonstrate the capabilities of the proposed method. 展开更多
关键词 method. saddle attracting
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Distributed Resource Allocation via Accelerated Saddle Point Dynamics 被引量:1
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作者 Wen-Ting Lin Yan-Wu Wang +1 位作者 Chaojie Li Xinghuo Yu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2021年第9期1588-1599,共12页
In this paper,accelerated saddle point dynamics is proposed for distributed resource allocation over a multi-agent network,which enables a hyper-exponential convergence rate.Specifically,an inertial fast-slow dynamica... In this paper,accelerated saddle point dynamics is proposed for distributed resource allocation over a multi-agent network,which enables a hyper-exponential convergence rate.Specifically,an inertial fast-slow dynamical system with vanishing damping is introduced,based on which the distributed saddle point algorithm is designed.The dual variables are updated in two time scales,i.e.,the fast manifold and the slow manifold.In the fast manifold,the consensus of the Lagrangian multipliers and the tracking of the constraints are pursued by the consensus protocol.In the slow manifold,the updating of the Lagrangian multipliers is accelerated by inertial terms.Hyper-exponential stability is defined to characterize a faster convergence of our proposed algorithm in comparison with conventional primal-dual algorithms for distributed resource allocation.The simulation of the application in the energy dispatch problem verifies the result,which demonstrates the fast convergence of the proposed saddle point dynamics. 展开更多
关键词 Accelerated saddle point dynamic distributed resource allocation hyper-exponential stability power dispatch
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HESSIAN MATRIX BASED SADDLE POINT DETECTION FOR GRANULES SEGMENTATION IN 2D IMAGE 被引量:4
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作者 Chen Ken Wang Yicong Yang Rener 《Journal of Electronics(China)》 2008年第6期728-736,共9页
Segmenting the touching objects in an image has been remaining as a hot subject due to the problematic complexities, and a vast number of algorithms designed to tackle this issue have come into being since a decade ag... Segmenting the touching objects in an image has been remaining as a hot subject due to the problematic complexities, and a vast number of algorithms designed to tackle this issue have come into being since a decade ago. In this paper, a new granule segmentation algorithm is developed using saddle point as the cutting point. The image is binarized and then sequentially eroded to form a gray-scale topographic counterpart, followed by using Hessian matrix computation to search for the saddle point. The segmentation is performed by cutting through the saddle point and along the maximal gradient path on the topographic surface. The results of the algorithm test on the given real images indicate certain superiorities in both the segmenting robustness and execution time to the referenced methods. 展开更多
关键词 HESSIAN矩阵 图像分区 鞍点检测 二维图像
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Thermal Fission Rate Calculated Numerically by Particles Multi-passing over SaddlePoint 被引量:3
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作者 LIULing BAOJing-Dong 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第2期273-278,共6页
Langevin simulation of the particles multi-passing over the saddle point is proposed to calculate thermal fission rate.Due to finite friction and the corresponding thermal flutuation,a backstreaming exists in the proc... Langevin simulation of the particles multi-passing over the saddle point is proposed to calculate thermal fission rate.Due to finite friction and the corresponding thermal flutuation,a backstreaming exists in the process of the particle descent from the saddle to the scissio.This leads to that the diffusion behind the saddle point has influence upon the stationary flow across the saddle point.A dynamical correction factor,as a ratio of the flows of multi-and firstoverpassing the saddle point,is evaluated analytically.The results show that the fission rate calculated by the particles multi-passing over the saddle point is lower than the one calculated by the particle firstly passing over the saddle point,and the fomer approaches the results at the scission point. 展开更多
关键词 Langevin模拟 热裂变率 粒子多通道支座点 稳态流 动力学修正因素 粒子物理
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THE CHARACTERIZATION OF EFFICIENCY AND SADDLE POINT CRITERIA FOR MULTIOBJECTIVE OPTIMIZATION PROBLEM WITH VANISHING CONSTRAINTS
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作者 Anurag JAYSWAL Vivek SINGH 《Acta Mathematica Scientia》 SCIE CSCD 2019年第2期382-394,共13页
In this article, we focus to study about modified objective function approach for multiobjective optimization problem with vanishing constraints. An equivalent η-approximated multiobjective optimization problem is co... In this article, we focus to study about modified objective function approach for multiobjective optimization problem with vanishing constraints. An equivalent η-approximated multiobjective optimization problem is constructed by a modification of the objective function in the original considered optimization problem. Furthermore, we discuss saddle point criteria for the aforesaid problem. Moreover, we present some examples to verify the established results. 展开更多
关键词 MULTIOBJECTIVE optimization problem with VANISHING CONSTRAINTS efficient solution INVEXITY η-Lagrange function saddle point
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MINIMAX THEOREMS FOR SUBCONVEXLIKEFUNCTIONS WITH APPLICATIONS TO SADDLEPOINT PROBLEMS
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作者 刘先忠 胡适耕 刘金山 《Acta Mathematica Scientia》 SCIE CSCD 2002年第1期115-122,共8页
In this paper some minimax theorems are presented for subconvexlike functions. These are then applied to obtain saddle point theorems.
关键词 subconvex set subconvexlike function minimax theorem saddle point theorem
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MINIMAX THEOREM AND SADDLE POINT THEOREM WITHOUT LINEAR STRUCTURE
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作者 郑喜印 温忠粦 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1998年第4期375-380,共6页
In this paper, a new kind of concavity of a function defined on a set without linear structure is introduced and a generalization of Fam Ky inequality is given. Minimax theorem in a general topological space is obtain... In this paper, a new kind of concavity of a function defined on a set without linear structure is introduced and a generalization of Fam Ky inequality is given. Minimax theorem in a general topological space is obtained. Moreover, a saddle point theorem on a topological space without any linear structure is established. 展开更多
关键词 minimax theorem saddle point theorem topological space
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Saddle Point Solution for System with Parameter Uncertainties
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作者 Abiola Bankole T. C. Obiwuru 《Advances in Pure Mathematics》 2013年第8期685-688,共4页
In this paper, we consider dynamical system, in the presence of parameter uncertainties. We apply max-min principles to determine the saddle point solution for the class of differential game arising from the associate... In this paper, we consider dynamical system, in the presence of parameter uncertainties. We apply max-min principles to determine the saddle point solution for the class of differential game arising from the associated dynamical system. We also provide sufficient condition for the existence of this saddle point. 展开更多
关键词 PARAMETER Uncertainty MIN-MAX PRINCIPLES saddle Point DIFFERENTIAL GAMES
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Open Loop Saddle Point on Linear Quadratic Stochastic Differential Games
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作者 WANG JUN 《Communications in Mathematical Research》 CSCD 2014年第1期11-22,共12页
In this paper, we deal with one kind of two-player zero-sum linear quadratic stochastic differential game problem. We give the existence of an open loop saddle point if and only if the lower and upper values exist.
关键词 stochastic differential game saddle point open loop strategy
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An automatic arc welding machine for saddle joint seams on large diameter cylinders
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作者 张忠厚 陈基勇 石运伟 《China Welding》 EI CAS 1999年第2期70-75,共6页
This paper deals with the structure, components, characteristics and work principle of a newly developed automatic arc welding machine for saddle joint seams on large diameter cylinders. The equations for designing th... This paper deals with the structure, components, characteristics and work principle of a newly developed automatic arc welding machine for saddle joint seams on large diameter cylinders. The equations for designing the geometry and dimensions of the cam controlling the moving locus of the welding torch have been derived. This welding machine has successfully been used in automatic welding saddle joint seams on boiler drums with good results and low cost. 展开更多
关键词 large diameter cylinders automatic arc welding machine saddle joint seam
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Rhinoplasty for Saddle Nose with Sarcoidosis
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作者 Masaki Yazawa Hayato Nagashima +1 位作者 Katsuya Suzuki Kazuo Kishi 《Surgical Science》 2015年第6期227-231,共5页
Background: Cases of acquired saddle nose have been reported;however, reports of sarcoidosis with acquired saddle nose are very rare. The main cause of sarcoidosis is estimated to be an abnormal immune reaction rather... Background: Cases of acquired saddle nose have been reported;however, reports of sarcoidosis with acquired saddle nose are very rare. The main cause of sarcoidosis is estimated to be an abnormal immune reaction rather than infection. Aim: Rhinoplasty using an autologous rib was planned and performed without plate fixation. Case Presentation: Our patient was diagnosed with sarcoidosis at the age of 25 years. She developed nasal congestion and rhinitis at the age of 42 years. Her nose began to show the saddle nose deformity at the age of 43 years. A rhinoplasty using an autologous rib was performed without plate fixation. Conclusion: After the operation, her nose maintained a favorable shape without sarcoidosis worsening. This use of rhinoplasty for treating saddle nose possibly prevents the worsening of sarcoidosis. 展开更多
关键词 saddle NOSE SARCOIDOSIS Rhinplasty
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