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Valence Bands Convergence in p-Type CoSb_(3) through Electronegative Fluorine Filling
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作者 黄写格 李家良 +5 位作者 马浩钦 李昌隆 刘天乐 段波 翟鹏程 李国栋 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第7期87-94,共8页
Band convergence is considered to be a strategy with clear benefits for thermoelectric performance,generally favoring the co-optimization of conductivity and Seebeck coefficients,and the conventional means include ele... Band convergence is considered to be a strategy with clear benefits for thermoelectric performance,generally favoring the co-optimization of conductivity and Seebeck coefficients,and the conventional means include elemental filling to regulate the band.However,the influence of the most electronegative fluorine on the CoSb_(3) band remains unclear.We carry out density-functional-theory calculations and show that the valence band maximum gradually shifts downward with the increase of fluorine filling,lastly the valence band maximum converges to the highly degenerated secondary valence bands in fluorine-filled skutterudites. 展开更多
关键词 VALENCE convergence BANDS
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Some convergence theorems of fuzzy concave integral on fuzzyσ-algebra
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作者 SUN Rong 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第3期438-447,共10页
In this paper,we consider the extension of the concave integral from classical crispσ-algebra to fuzzyσ-algebra of fuzzy sets.Firstly,the concept of fuzzy concave integral on a fuzzy set is introduced.Secondly,some ... In this paper,we consider the extension of the concave integral from classical crispσ-algebra to fuzzyσ-algebra of fuzzy sets.Firstly,the concept of fuzzy concave integral on a fuzzy set is introduced.Secondly,some important properties of such integral are discussed.Finally,various kinds of convergence theorems of a sequence of fuzzy concave integrals are proved. 展开更多
关键词 convergence theorems fuzzy concave integral fuzzyσ-algebra
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Multi-modal knowledge graph inference via media convergence and logic rule
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作者 Feng Lin Dongmei Li +5 位作者 Wenbin Zhang Dongsheng Shi Yuanzhou Jiao Qianzhong Chen Yiying Lin Wentao Zhu 《CAAI Transactions on Intelligence Technology》 SCIE EI 2024年第1期211-221,共11页
Media convergence works by processing information from different modalities and applying them to different domains.It is difficult for the conventional knowledge graph to utilise multi-media features because the intro... Media convergence works by processing information from different modalities and applying them to different domains.It is difficult for the conventional knowledge graph to utilise multi-media features because the introduction of a large amount of information from other modalities reduces the effectiveness of representation learning and makes knowledge graph inference less effective.To address the issue,an inference method based on Media Convergence and Rule-guided Joint Inference model(MCRJI)has been pro-posed.The authors not only converge multi-media features of entities but also introduce logic rules to improve the accuracy and interpretability of link prediction.First,a multi-headed self-attention approach is used to obtain the attention of different media features of entities during semantic synthesis.Second,logic rules of different lengths are mined from knowledge graph to learn new entity representations.Finally,knowledge graph inference is performed based on representing entities that converge multi-media features.Numerous experimental results show that MCRJI outperforms other advanced baselines in using multi-media features and knowledge graph inference,demonstrating that MCRJI provides an excellent approach for knowledge graph inference with converged multi-media features. 展开更多
关键词 logic rule media convergence multi-modal knowledge graph inference representation learning
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Spatial Differentiation and Convergence Trend of High-quality Development Level of China’s Tourism Economy
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作者 CAO Shanshan HE Zhaoli +2 位作者 NIU Jinlan WANG Songmao ZHAO Lei 《Chinese Geographical Science》 SCIE CSCD 2024年第2期230-249,共20页
This paper aims to interpret the connotation of high-quality development of tourism economy(HQTE)from the perspective of the new development concepts of innovation,coordination,green,openness and sharing,and then to e... This paper aims to interpret the connotation of high-quality development of tourism economy(HQTE)from the perspective of the new development concepts of innovation,coordination,green,openness and sharing,and then to evaluate the spatial differenti-ation of China’s HQTE based on provincial panel data from 2009 to 2018.Specifically,we employ the spatial convergence model to ex-plore the absolute and conditionalβconvergence trends of HQTE in the whole country and the eastern,central and western regions of China.Our empirical results reveal that:1)within the decade,from 2009 to 2018,regions of China with the highest HQTE index is its eastern region followed by the central region and then the western region,but the fastest growing one is the western region of China fol-lowed by the central region and then the eastern region.2)Whether or not the spatial effect is included,there are absolute and condition-alβconvergence in HQTE in the whole country and aforementioned three regions.3)The degree of government attention as well as the level of economic development and location accessibility are the positive driving factors for the convergence of HQTE in the whole country and the three regions.The degree of marketization and human capital have not passed the significance test either in the whole country or in the three regions.The above conclusions could deepen the understanding of the regional imbalance and spatial conver-gence characteristics of HQTE,clarify the primary development objects,and accomplish the goal of China’s HQTE. 展开更多
关键词 new development concepts high-quality development of tourism economy(HQTE) spatial convergence China
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The Convergence Rate of Fréchet Distribution under the Second-Order Regular Variation Condition
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作者 Xilai Dai 《Journal of Applied Mathematics and Physics》 2024年第5期1597-1605,共9页
In this article we consider the asymptotic behavior of extreme distribution with the extreme value index γ>0 . The rates of uniform convergence for Fréchet distribution are constructed under the second-order ... In this article we consider the asymptotic behavior of extreme distribution with the extreme value index γ>0 . The rates of uniform convergence for Fréchet distribution are constructed under the second-order regular variation condition. 展开更多
关键词 convergence Rate Second-Order Regular Variation Condition Fréchet Distribution Extreme Value Index
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Dα-convergence on L-fuzzy Topological Space 被引量:1
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作者 孟广武 王秀平 《模糊系统与数学》 CSCD 北大核心 2008年第5期47-50,共4页
在L-拓扑空间中,利用Dα-闭集推广了远域的概念,定义了L-子集的层次收敛,建立了网的层次收敛理论。
关键词 模糊拓扑学 -极限点 -闭集 -收敛性
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The Convergence Characteristic of the Forward I-V Characteristic Curves of a Semiconductor Silicon Barrier at Different Temperatures
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作者 苗庆海 卢烁今 +2 位作者 张兴华 宗福建 朱阳军 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第4期663-667,共5页
The /-V-(T) characteristic curves of p-n junctions with the forward voltage as the independent variable, the logarithm of forward current as the dependent variable, and the junction temperature as the parameter, alm... The /-V-(T) characteristic curves of p-n junctions with the forward voltage as the independent variable, the logarithm of forward current as the dependent variable, and the junction temperature as the parameter, almost converge at one point in the first quadrant. The voltage corresponding with the convergence point nearly equals the bandgap of the semiconductor material. This convergence point can be used to obtain the I-V characteristic curve at any temperature. 展开更多
关键词 semiconductor barrier bandgap convergent point forward I-V characteristic curves
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Convergence Analysis of the Numerical Solution for Cathode Design of Aero-engine Blades in Electrochemical Machining 被引量:17
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作者 Li Zhiyong Niu Zongwei 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2007年第6期570-576,共7页
As a main difficult problem encountered in electrochemical machining (ECM), the cathode design is tackled, at present, with various numerical analysis methods such as finite difference, finite element and boundary e... As a main difficult problem encountered in electrochemical machining (ECM), the cathode design is tackled, at present, with various numerical analysis methods such as finite difference, finite element and boundary element methods. Among them, the finite element method presents more flexibility to deal with the irregularly shaped workpieces. However, it is very difficult to ensure the convergence of finite element numerical approach. This paper proposes an accurate model and a finite element numerical approach of cathode design based on the potential distribution in inter-electrode gap. In order to ensure the convergence of finite element numerical approach and increase the accuracy in cathode design, the cathode shape should be iterated to eliminate the design errors in computational process. Several experiments are conducted to verify the machining accuracy of the designed cathode. The experimental results have proven perfect convergence and good computing accuracy of the proposed finite element numerical approach by the high surface quality and dimensional accuracy of the machined blades. 展开更多
关键词 electrochemical machining aero-engine blade cathode design convergence analysis
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法舒地尔缓解β-淀粉样蛋白1-42诱导的SH-SY5Y细胞凋亡
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作者 郭敏芳 张慧宇 +3 位作者 章培军 苏琴 贾思玮 尉杰忠 《中国组织工程研究》 CAS 北大核心 2025年第23期4939-4946,共8页
背景:法舒地尔对阿尔茨海默病小鼠脑内的线粒体动力学有调节作用,并且可以抑制神经炎症,但能否调节线粒体自噬和NLRP3炎症小体进而减轻β-淀粉样蛋白毒性尚不清楚。目的:探究法舒地尔对β-淀粉样蛋白1-42诱导的人源神经母细胞瘤细胞株SH... 背景:法舒地尔对阿尔茨海默病小鼠脑内的线粒体动力学有调节作用,并且可以抑制神经炎症,但能否调节线粒体自噬和NLRP3炎症小体进而减轻β-淀粉样蛋白毒性尚不清楚。目的:探究法舒地尔对β-淀粉样蛋白1-42诱导的人源神经母细胞瘤细胞株SH-SY5Y凋亡和线粒体自噬以及NLRP3炎症小体的调节作用。方法:将SH-SY5Y细胞接种于孔板内,细胞贴壁后分3组干预:对照组不加入任何药物,模型组加入20μmol/L β-淀粉样蛋白1-42,法舒地尔组同时加入20μmol/L β-淀粉样蛋白1-42与15 mg/L法舒地尔,干预24 h后,采用MTT法检测细胞活性,TUNEL染色检测细胞凋亡,qRT-PCR和Western blot检测凋亡相关蛋白表达,免疫荧光染色和Western blot检测线粒体自噬相关蛋白表达,免疫荧光染色和Western blot检测NLRP3炎症小体相关蛋白表达。结果与结论:(1)与对照组比较,模型组细胞活性降低、凋亡率升高(P<0.05);与模型组比较,法舒地尔组细胞活性升高、凋亡率降低(P<0.05);(2)qRT-PCR和Western blot检测结果显示,与对照组比较,模型组细胞Bax mRNA与蛋白表达升高(P<0.05),Bcl-2 mRNA与蛋白表达降低(P<0.05);与模型组比较,法舒地尔组细胞Bax mRNA与蛋白表达降低(P<0.05),Bcl-2 mRNA与蛋白表达升高(P<0.05);(3)免疫荧光染色和Western blot检测结果显示,与对照组相比,模型组细胞PINK1、帕金森病蛋白和LC3蛋白表达降低(P<0.05),p62蛋白表达升高(P<0.05);与模型组相比,法舒地尔组细胞PINK1、帕金森病蛋白和LC3蛋白表达升高(P<0.05),p62蛋白表达降低(P<0.05);(4)免疫荧光染色和Western blot检测结果显示,与对照组相比,模型组细胞NLRP3、ASC、Caspase-1和白细胞介素1β蛋白表达升高(P<0.05);与模型组相比,法舒地尔组细胞NLRP3、ASC、Caspase-1和白细胞介素1β蛋白表达降低(P<0.05);(5)结果表明,法舒地尔可以减轻β-淀粉样蛋白1-42诱导的SH-SY5Y细胞凋亡,其机制可能与激活线粒体自噬且抑制NLRP3炎症小体激活有关。 展开更多
关键词 法舒地尔 Β-淀粉样蛋白 神经细胞 细胞凋亡 线粒体自噬 炎症小体
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GLOBAL CONVERGENCE RESULTS OF A THREE TERM MEMORY GRADIENT METHOD WITH A NON-MONOTONE LINE SEARCH TECHNIQUE 被引量:12
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作者 孙清滢 《Acta Mathematica Scientia》 SCIE CSCD 2005年第1期170-178,共9页
In this paper, a new class of three term memory gradient method with non-monotone line search technique for unconstrained optimization is presented. Global convergence properties of the new methods are discussed. Comb... In this paper, a new class of three term memory gradient method with non-monotone line search technique for unconstrained optimization is presented. Global convergence properties of the new methods are discussed. Combining the quasi-Newton method with the new method, the former is modified to have global convergence property. Numerical results show that the new algorithm is efficient. 展开更多
关键词 Non-linear programming three term memory gradient method convergence non-monotone line search technique numerical experiment
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Influence of longwall gateroad convergence on the process of mine ventilation network-model tests 被引量:3
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作者 Andrzej Walentek Tomasz Janoszek +1 位作者 Stanis?aw Prusek Aleksander Wrana 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2019年第4期585-590,共6页
Hard coal mines are required to constantly ventilate mine workings to ensure that the air composition is at a certain humidity and temperature level that is comfortable for underground mine workers,especially in deep ... Hard coal mines are required to constantly ventilate mine workings to ensure that the air composition is at a certain humidity and temperature level that is comfortable for underground mine workers,especially in deep deposits.All underground workings,which are part of the mine ventilation network,should be ventilated in a way that allows maintaining proper oxygen concentration not lower than 19%(by volume),and limits concentration of gases in the air such as methane,carbon monoxide or carbon dioxide.The air flow in the mine ventilation network may be disturbed due to the natural convergence(deformation)and lead to change in its original cross-section.Reducing the cross-sectional area of the mining excavation causes local resistances in the air flow and changes in aerodynamic potentials,which leads to emergency states in the mine ventilation network.This paper presents the results of numerical simulations of the influence of gateroad convergence on the ventilation process of a selected part of the mine ventilation network.The gateroad convergence was modelled with the finite element software PHASE 2.The influence of changes in the cross-sectional area of the gateroad on the ventilation process was carried out using the computational fluid dynamics software Ansys-Fluent. 展开更多
关键词 GEOMECHANICS convergence NUMERICAL modelling Ventilation PROCESS SUPPORT
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Target Tracking Algorithm Using Finite-time Convergence Smooth Second-order Sliding Mode Controller for Mobile Robots 被引量:4
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作者 GE Lianzheng ZHAO Lijun GAO Tong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2011年第3期414-419,共6页
Target tracking control for wheeled mobile robot (WMR) need resolve the problems of kinematics model and tracking algorithm.High-order sliding mode control is a valid method used in the nonlinear tracking control sy... Target tracking control for wheeled mobile robot (WMR) need resolve the problems of kinematics model and tracking algorithm.High-order sliding mode control is a valid method used in the nonlinear tracking control system,which can eliminate the chattering of sliding mode control.Currently there lacks the research of robustness and uncertain factors for high-order sliding mode control.To address the fast convergence and robustness problems of tracking target,the tracking mathematical model of WMR and the target is derived.Based on the finite-time convergence theory and second order sliding mode method,a nonlinear tracking algorithm is designed which guarantees that WMR can catch the target in finite time.At the same time an observer is applied to substitute the uncertain acceleration of the target,then a smooth nonlinear tracking algorithm is proposed.Based on Lyapunov stability theory and finite-time convergence,a finite time convergent smooth second order sliding mode controller and a target tracking algorithm are designed by using second order sliding mode method.The simulation results verified that WMR can catch up the target quickly and reduce the control discontinuity of the velocity of WMR. 展开更多
关键词 mobile robots second order sliding mode finite-time convergence OBSERVER
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ASYMPTOTIC APPROXIMATION METHOD AND ITS CONVERGENCE ON SEMI-INFINITE PROGRAMMING 被引量:3
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作者 万仲平 王先甲 +1 位作者 何炬林 贾世会 《Acta Mathematica Scientia》 SCIE CSCD 2006年第1期17-24,共8页
The aim of this article is to discuss an asymptotic approximation model and its convergence for the minimax semi-infinite programming problem. An asymptotic surrogate constraints method for the minimax semi-infinite p... The aim of this article is to discuss an asymptotic approximation model and its convergence for the minimax semi-infinite programming problem. An asymptotic surrogate constraints method for the minimax semi-infinite programming problem is presented by making use of two general discrete approximation methods. Simultaneously, the consistence and the epi-convergence of the asymptotic approximation problem are discussed. 展开更多
关键词 Semi-infinite programming asymptotic approximation convergence
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CONVERGENCE ANALYSIS OF RUNGE-KUTTA METHODS FOR A CLASS OF RETARDED DIFFERENTIAL ALGEBRAIC SYSTEMS 被引量:4
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作者 肖飞雁 张诚坚 《Acta Mathematica Scientia》 SCIE CSCD 2010年第1期65-74,共10页
This article deals with a class of numerical methods for retarded differential algebraic systems with time-variable delay. The methods can be viewed as a combination of Runge-Kutta methods and Lagrange interpolation. ... This article deals with a class of numerical methods for retarded differential algebraic systems with time-variable delay. The methods can be viewed as a combination of Runge-Kutta methods and Lagrange interpolation. A new convergence concept, called DA-convergence, is introduced. The DA-convergence result for the methods is derived. At the end, a numerical example is given to verify the computational effectiveness and the theoretical result. 展开更多
关键词 convergence Runge-Kutta Methods Lagrange interpolation retarded dif-ferential algebraic systems
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A Note on the Convergence of Orlicz-Bochner Spaces with the Luxemburg Norm 被引量:3
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作者 张剑尘 《Journal of Shanghai University(English Edition)》 CAS 2003年第4期358-360,共3页
In this paper, the convergence of the Orlicz-Bochner function spaces with the Luxemburg norm was proved.
关键词 convergence modular Orlicz-Bochner space Luxemgurg norm.
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Complete Convergence Properties of the Sums for -mixing Sequences of Random Variables 被引量:5
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作者 WU Yan-chun WU Qun-ying 《Chinese Quarterly Journal of Mathematics》 CSCD 2011年第2期159-163,共5页
This paper discusses complete convergence properties of the sums of -mixing random sequences.As a result,we improve the corresponding results of Wu Qunying(2001). And extended the Baum and Katz complete convergence ... This paper discusses complete convergence properties of the sums of -mixing random sequences.As a result,we improve the corresponding results of Wu Qunying(2001). And extended the Baum and Katz complete convergence to the case of -mixing random sequences by moment inequality and truncating without necessarily adding any extra conditions. 展开更多
关键词 -mixing random sequences complete convergence moment condition
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Self-adaptive strategy for one-dimensional finite element method based on EEP method with optimal super-convergence order 被引量:4
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作者 袁驷 邢沁妍 +1 位作者 王旭 叶康生 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2008年第5期591-602,共12页
Based on the newly-developed element energy projection (EEP) method with optimal super-convergence order for computation of super-convergent results, an improved self-adaptive strategy for one-dimensional finite ele... Based on the newly-developed element energy projection (EEP) method with optimal super-convergence order for computation of super-convergent results, an improved self-adaptive strategy for one-dimensional finite element method (FEM) is proposed. In the strategy, a posteriori errors are estimated by comparing FEM solutions to EEP super-convergent solutions with optimal order of super-convergence, meshes are refined by using the error-averaging method. Quasi-FEM solutions are used to replace the true FEM solutions in the adaptive process. This strategy has been found to be simple, clear, efficient and reliable. For most problems, only one adaptive step is needed to produce the required FEM solutions which pointwise satisfy the user specified error tolerances in the max-norm. Taking the elliptical ordinary differential equation of the second order as the model problem, this paper describes the fundamental idea, implementation strategy and computational algorithm and representative numerical examples are given to show the effectiveness and reliability of the proposed approach. 展开更多
关键词 finite element method (FEM) self-adaptive solution super-convergence optimal convergence order element energy projection condensed shape functions
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Service-aware 6G:An intelligent and open network based on the convergence of communication,computing and caching 被引量:77
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作者 Yiqing Zhou Ling Liu +6 位作者 Lu Wang Ning Hui Xinyu Cui Jie Wu Yan Peng Yanli Qi Chengwen Xing 《Digital Communications and Networks》 SCIE 2020年第3期253-260,共8页
With the proliferation of the Internet of Things(IoT),various services are emerging with totally different features and requirements,which cannot be supported by the current fifth generation of mobile cellular network... With the proliferation of the Internet of Things(IoT),various services are emerging with totally different features and requirements,which cannot be supported by the current fifth generation of mobile cellular networks(5G).The future sixth generation of mobile cellular networks(6G)is expected to have the capability to support new and unknown services with changing requirements.Hence,in addition to enhancing its capability by 10–100 times compared with 5G,6G should also be intelligent and open to adapt to the ever-changing services in the IoT,which requires a convergence of Communication,Computing and Caching(3C).Based on the analysis of the requirements of new services for 6G,this paper identifies key enabling technologies for an intelligent and open 6G network,all featured with 3C convergence.These technologies cover fundamental and emerging topics,including 3C-based spectrum management,radio channel construction,delay-aware transmission,wireless distributed computing,and network self-evolution.From the detailed analysis of these 3C-based technologies presented in this paper,we can see that although they are promising to enable an intelligent and open 6G,more efforts are needed to realize the expected 6G network. 展开更多
关键词 6G convergence of 3C INTELLIGENT OPEN IOT
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Boundedness and convergence of perturbed corrections for helium-like ions in ground states 被引量:2
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作者 赵云辉 海文华 +1 位作者 赵乘麟 罗小兵 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第5期1720-1728,共9页
Applying the improved Rayleigh SchrSdinger perturbation theory based on an integral equation to helium-like ions in ground states and treating electron correlations as perturbations, we obtain the second-order correct... Applying the improved Rayleigh SchrSdinger perturbation theory based on an integral equation to helium-like ions in ground states and treating electron correlations as perturbations, we obtain the second-order corrections to wavefunctions consisting of a few terms and the third-order corrections to energicity. It is demonstrated that the corrected wavefunctions are bounded and quadratically integrable, and the corresponding perturbation series is convergent. The results clear off the previous distrust for the convergence in the quantum perturbation theory and show a reciprocal development on the quantum perturbation problem of the ground state helium-like systems. 展开更多
关键词 helium-like ion perturbation correction BOUNDEDNESS convergence
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STABILITY AND SUPER CONVERGENCE ANALYSIS OF ADI-FDTD FOR THE 2D MAXWELL EQUATIONS IN A LOSSY MEDIUM 被引量:2
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作者 高理平 《Acta Mathematica Scientia》 SCIE CSCD 2012年第6期2341-2368,共28页
Several new energy identities of the two dimenslonal(2D) Maxwell equations in a lossy medium in the case of the perfectly electric conducting boundary conditions are proposed and proved. These identities show a new ... Several new energy identities of the two dimenslonal(2D) Maxwell equations in a lossy medium in the case of the perfectly electric conducting boundary conditions are proposed and proved. These identities show a new kind of energy conservation in the Maxwell system and provide a new energy method to analyze the alternating direction im- plicit finite difference time domain method for the 2D Maxwell equations (2D-ADI-FDTD). It is proved that 2D-ADI-FDTD is approximately energy conserved, unconditionally sta- ble and second order convergent in the discrete L2 and H1 norms, which implies that 2D-ADI-FDTD is super convergent. By this super convergence, it is simply proved that the error of the divergence of the solution of 2D-ADI-FDTD is second order accurate. It is also proved that the difference scheme of 2D-ADI-FDTD with respect to time t is second order convergent in the discrete H1 norm. Experimental results to confirm the theoretical analysis on stability, convergence and energy conservation are presented. 展开更多
关键词 STABILITY convergence energy conservation ADI-FDTD Maxwell equations
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