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Numerical Methods for a Class of Quadratic Matrix Equations
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作者 GUAN Jinrui WANG Zhixin SHAO Rongxia 《应用数学》 北大核心 2024年第4期962-970,共9页
Quadratic matrix equations arise in many elds of scienti c computing and engineering applications.In this paper,we consider a class of quadratic matrix equations.Under a certain condition,we rst prove the existence of... Quadratic matrix equations arise in many elds of scienti c computing and engineering applications.In this paper,we consider a class of quadratic matrix equations.Under a certain condition,we rst prove the existence of minimal nonnegative solution for this quadratic matrix equation,and then propose some numerical methods for solving it.Convergence analysis and numerical examples are given to verify the theories and the numerical methods of this paper. 展开更多
关键词 Quadratic matrix equation M-matrix Minimal nonnegative solution Newton method Bernoulli method
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Carbon matrix effects on the micro-structure and performance of Pt nanowire cathode prepared by decal transfer method 被引量:4
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作者 Zhaoxu Wei An He +1 位作者 Kaihua Su Sheng Sui 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2015年第2期213-218,共6页
High performance cathode for polymer electrolyte membrane fuel cell was prepared by depositing Pt nanowires in a carbon matrix coated on a substrate, and using decal transfer method to fabricate the membrane electrode... High performance cathode for polymer electrolyte membrane fuel cell was prepared by depositing Pt nanowires in a carbon matrix coated on a substrate, and using decal transfer method to fabricate the membrane electrode assembly. The effects of carbon and ionomer contents on the electrode micro-structure and fuel cell performance are investigated by physical characterization and single cell testing. The Pt nanowires are gradient distributed across the cathode thickness, and more Pt exists near the membrane. Both the carbon and ionomer contents can affect the Pt nanowires distribution and aggregation. In addition, the carbon loading dominates the transport distance of gas and proton, and the ionomer content affects the triple phase boundaries and porosity in the cathode. The optimal structure of Pt nanowire cathode is obtained at 0.10 mg·cm^-2 carbon loading and 10 wt% ionomer. 展开更多
关键词 Pt nanowire carbon matrix IONOMER decal transfer method polymer electrolyte membrane fuel cell
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A Rework Reduction Mechanism in Complex Projects Using Design Structure Matrix Clustering Methods 被引量:1
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作者 XU Haiyan ZHAO Shinan +1 位作者 Amin MAHMOUDI Mohammad Reza FEYLIZADEH 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2019年第2期264-279,共16页
To reduce the uncertainty and reworks in complex projects,a novel mechanism is systematically developed in this paper based on two classical design structure matrix(DSM)clustering methods:Loop searching method(LSM)and... To reduce the uncertainty and reworks in complex projects,a novel mechanism is systematically developed in this paper based on two classical design structure matrix(DSM)clustering methods:Loop searching method(LSM)and function searching method(FSM).Specifically,the optimal working areas for the two clustering methods are first obtained quantitatively in terms of non-zero fraction(NZF)and singular value modularity index(SMI),in which the whole working area is divided into six sub-zones.Then,a judgement procedure is proposed for conveniently choosing the optimal DSM clustering method,which makes it easy to determine which DSM clustering method performs better for a given case.Subsequently,a conceptual model is constructed to assist project managers in effectively analyzing the network of projects and greatly reducing reworks in complex projects by defining preventive actions.Finally,the aircraft design process is presented to show how the proposed judgement mechanism can be utilized to reduce the reworks in actual projects. 展开更多
关键词 project management design structure matrix LOOP SEARCHING method FUNCTION SEARCHING method reworks
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Accurate machine learning models based on small dataset of energetic materials through spatial matrix featurization methods 被引量:6
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作者 Chao Chen Danyang Liu +4 位作者 Siyan Deng Lixiang Zhong Serene Hay Yee Chan Shuzhou Li Huey Hoon Hng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第12期364-375,I0009,共13页
A large database is desired for machine learning(ML) technology to make accurate predictions of materials physicochemical properties based on their molecular structure.When a large database is not available,the develo... A large database is desired for machine learning(ML) technology to make accurate predictions of materials physicochemical properties based on their molecular structure.When a large database is not available,the development of proper featurization method based on physicochemical nature of target proprieties can improve the predictive power of ML models with a smaller database.In this work,we show that two new featurization methods,volume occupation spatial matrix and heat contribution spatial matrix,can improve the accuracy in predicting energetic materials' crystal density(ρ_(crystal)) and solid phase enthalpy of formation(H_(f,solid)) using a database containing 451 energetic molecules.Their mean absolute errors are reduced from 0.048 g/cm~3 and 24.67 kcal/mol to 0.035 g/cm~3 and 9.66 kcal/mol,respectively.By leave-one-out-cross-validation,the newly developed ML models can be used to determine the performance of most kinds of energetic materials except cubanes.Our ML models are applied to predict ρ_(crystal) and H_(f,solid) of CHON-based molecules of the 150 million sized PubChem database,and screened out 56 candidates with competitive detonation performance and reasonable chemical structures.With further improvement in future,spatial matrices have the potential of becoming multifunctional ML simulation tools that could provide even better predictions in wider fields of materials science. 展开更多
关键词 Small database machine learning Energetic materials screening Spatial matrix featurization method Crystal density Formation enthalpy n-Body interactions
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Kohn-Sham Density Matrix and the Kernel Energy Method 被引量:1
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作者 POLKOSNIK Walter MASSA Lou 《物理化学学报》 SCIE CAS CSCD 北大核心 2018年第6期656-661,共6页
The kernel energy method(KEM) has been shown to provide fast and accurate molecular energy calculations for molecules at their equilibrium geometries.KEM breaks a molecule into smaller subsets,called kernels,for the p... The kernel energy method(KEM) has been shown to provide fast and accurate molecular energy calculations for molecules at their equilibrium geometries.KEM breaks a molecule into smaller subsets,called kernels,for the purposes of calculation.The results from the kernels are summed according to an expression characteristic of KEM to obtain the full molecule energy.A generalization of the kernel expansion to density matrices provides the full molecule density matrix and orbitals.In this study,the kernel expansion for the density matrix is examined in the context of density functional theory(DFT) Kohn-Sham(KS) calculations.A kernel expansion for the one-body density matrix analogous to the kernel expansion for energy is defined,and is then converted into a normalizedprojector by using the Clinton algorithm.Such normalized projectors are factorizable into linear combination of atomic orbitals(LCAO) matrices that deliver full-molecule Kohn-Sham molecular orbitals in the atomic orbital basis.Both straightforward KEM energies and energies from a normalized,idempotent density matrix obtained from a density matrix kernel expansion to which the Clinton algorithm has been applied are compared to reference energies obtained from calculations on the full system without any kernel expansion.Calculations were performed both for a simple proof-of-concept system consisting of three atoms in a linear configuration and for a water cluster consisting of twelve water molecules.In the case of the proof-of-concept system,calculations were performed using the STO-3 G and6-31 G(d,p) bases over a range of atomic separations,some very far from equilibrium.The water cluster was calculated in the 6-31 G(d,p) basis at an equilibrium geometry.The normalized projector density energies are more accurate than the straightforward KEM energy results in nearly all cases.In the case of the water cluster,the energy of the normalized projector is approximately four times more accurate than the straightforward KEM energy result.The KS density matrices of this study are applicable to quantum crystallography. 展开更多
关键词 Kohn SHAM density matrix KERNEL energy method N-REPRESENTABILITY QUANTUM CRYSTALLOGRAPHY Watercluster
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Vibration analysis of fluid- structure interaction in water hammer based on transfer matrix method 被引量:1
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作者 GAO Hui TANG Xuelin 《排灌机械工程学报》 EI CSCD 北大核心 2016年第6期518-524,共7页
In consideration of the problem that the effect of conduit structure on water hammer has been ignored in the classical theory,the Poisson coupling between the fluid and the pipeline was studied and a fourteen-equation... In consideration of the problem that the effect of conduit structure on water hammer has been ignored in the classical theory,the Poisson coupling between the fluid and the pipeline was studied and a fourteen-equation mathematical model of fluid-structure interaction(FSI)was developed.Then,the transfer matrix method(TMM)was used to calculate the modal frequency,modal shape and frequency response.The results were compared with that in experiment to verify the correctness of the TMM and the results show that the fluid-structure coupling has a greater impact on the modal frequencies than the modal shape.Finally,the influence on the response spectrum of different damping ratios was studied and the results show that the natural frequency under different damping ratios has changed little but there is a big difference for the pressure spectrum.With the decreasing of damping ratio,the damping of the system on frequency spectrum is more and more significant and the dispersion and dissipation is more and more apparent.Therefore the appropriate damping ratio should be selected to minimize the effects of the vibration of the FSI.The results provide references for the theory research of FSI in the transient process. 展开更多
关键词 water hammer fluid-structure interaction transfer matrix method vibration analysis
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一种用于深空网天线组阵的基于归一化权的Matrix-Free Power Method 被引量:3
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作者 赵晓明 冯恩信 姜家持 《遥测遥控》 2009年第4期15-20,共6页
对深空网天线组阵中的几种信号相关算法作简要介绍,重点研究无需形成矩阵的幂的方法——Matrix-Free Power Method。通过理论分析,提出一种改进算法,即基于归一化权的Matrix-Free Power Method。理论计算和软件仿真结果均表明,基于归一... 对深空网天线组阵中的几种信号相关算法作简要介绍,重点研究无需形成矩阵的幂的方法——Matrix-Free Power Method。通过理论分析,提出一种改进算法,即基于归一化权的Matrix-Free Power Method。理论计算和软件仿真结果均表明,基于归一化权的Matrix-Free Power Method信噪比合成性能略优于原Matrix-Free Power Method。 展开更多
关键词 深空探测 天线组阵 matrix-FREE POWER method 权信噪比 归一化权
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AOR Iterative Method for Coupled Lyapunov Matrix Equations 被引量:3
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作者 ZHANG Shi-jun WANG Shi-heng WANG Ke 《Chinese Quarterly Journal of Mathematics》 2021年第2期141-148,共8页
An AOR(Accelerated Over-Relaxation)iterative method is suggested by introducing one more parameter than SOR(Successive Over-Relaxation)method for solving coupled Lyapunov matrix equations(CLMEs)that come from continuo... An AOR(Accelerated Over-Relaxation)iterative method is suggested by introducing one more parameter than SOR(Successive Over-Relaxation)method for solving coupled Lyapunov matrix equations(CLMEs)that come from continuous-time Markovian jump linear systems.The proposed algorithm improves the convergence rate,which can be seen from the given illustrative examples.The comprehensive theoretical analysis of convergence and optimal parameter needs further investigation. 展开更多
关键词 Coupled Lyapunov matrix equations AOR iterative method SOR iterative method Markovian jump systems
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Ranking Method for Complementary Judgment Matrixes with Fuzzy Numbers Based on Hausdorff Metric Distance 被引量:1
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作者 侯福均 吴祈宗 《Journal of Beijing Institute of Technology》 EI CAS 2005年第4期458-461,共4页
A method for ranking complementary judgment matrixes with traspezoidal fuzzy numbers based on Hausdorff metric distance and fuzzy compromise decision approach is proposed. With regard to fuzzy number complementary jud... A method for ranking complementary judgment matrixes with traspezoidal fuzzy numbers based on Hausdorff metric distance and fuzzy compromise decision approach is proposed. With regard to fuzzy number complementary judgment matrixes given by a decider group whose members have various weights, the expert's information was aggregated first by means of simple weight average(SWA) method and Bonissone calculational method. Hence a matrix including all the experts' preference information was got. Then the matrix' column members were added up and the fuzzy evaluation values of the alternatives were got. Lastly, the Hausdorff metric distance and fuzzy compromise decision approach were used to rank the fuzzy evaluation values and then the ranking values of all the alternatives were got. Because exact numbers and triangular fuzzy numbers could all be transformed into trapezoidal fuzzy numbers, the method developed can rank complementary judgment matrixes with trapezoidal fuzzy numbers, triangular fuzzy numbers and exact numbers as well. An illustrative example is also given to verify the developed method and to demonstrate its feasibility and practicality. 展开更多
关键词 complementary judgment matrix trapezoidal fuzzy number Bonissone calculational method fuzzy compromise decision approach Hausdorff metric distance
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Analysis of the flexural vibration of ship's tail shaft by transfer matrix method 被引量:1
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作者 贾小俊 范世东 《Journal of Marine Science and Application》 2008年第3期179-183,共5页
A ship's tail shaft has serious flexural vibration due to the cantilevered nature of the propeller's blades.Analysis of the nature frequency of flexural vibration is vital to be able to provide effective shock... A ship's tail shaft has serious flexural vibration due to the cantilevered nature of the propeller's blades.Analysis of the nature frequency of flexural vibration is vital to be able to provide effective shock absorption for a ship's tail shaft.A mathematic model of tail shaft flexural vibrations was built using the transfer matrix method.The nature frequency of flexural vibration for an electrically propelled ship's tail shaft was then analyzed,and an effective method for calculating it was proposed:a genetic algorithm(GA),which calculates the nature frequency of vibration of a system.Sample calculations,with comparisons by the Prohl method under conditions bearing isotropic support,showed this method to be practical.It should have significant impact on engineering design theory. 展开更多
关键词 transfer matrix method flexural vibration nature frequency genetic algorithm
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Thermodynamic stability of interacting fermions system with matrix eigenvalue method
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作者 覃昉 陈继胜 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第7期2654-2658,共5页
A matrix eigenvalue method is applied to analyse the thermodynamic stability of two-component interacting fermions. The non-relativistic and ultra-relativistic d = 1, 2, 3 dimensions have been discussed in detail, res... A matrix eigenvalue method is applied to analyse the thermodynamic stability of two-component interacting fermions. The non-relativistic and ultra-relativistic d = 1, 2, 3 dimensions have been discussed in detail, respectively. The corresponding stability region has been given according to the two-body interaction strength and the particle number density ratio. 展开更多
关键词 thermodynamic stability fermions mixing matrix eigenvalue method
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Energy eigenvalues from an analytical transfer matrix method
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作者 何英 张凡明 +1 位作者 杨艳芳 李春芳 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第4期50-55,共6页
A detailed procedure based on an analytical transfer matrix method is presented to solve bound-state problems. The derivation is strict and complete. The energy eigenvalues for an arbitrary one-dimensional potential c... A detailed procedure based on an analytical transfer matrix method is presented to solve bound-state problems. The derivation is strict and complete. The energy eigenvalues for an arbitrary one-dimensional potential can be obtained by the method. The anharmonic oscillator potential and the rational potential are two important examples. Checked by numerical techniques, the results for the two potentials by the present method are proven to be exact and reliable. 展开更多
关键词 analytical transfer matrix method energy eigenvalues bound state one-dimensional potential
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The analytical transfer matrix method for quantum reflection
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作者 许田 曹庄琪 方靖淮 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第4期56-61,共6页
In this paper, the analytical transfer matrix method (ATMM) is applied to study the properties of quantum reflection in three systems: a sech2 barrier, a ramp potential and an inverse harmonic oscillator. Our resul... In this paper, the analytical transfer matrix method (ATMM) is applied to study the properties of quantum reflection in three systems: a sech2 barrier, a ramp potential and an inverse harmonic oscillator. Our results agree with those obtained by Landau and Lifshitz [Landau L D and Lifshitz E M 1977 Quantum Mechanics (Non-relativistic Theory) (New York: Pergamon)], which proves that ATMM is a simple and effective method for quantum reflection. 展开更多
关键词 analytical transfer matrix method quantum reflection reflection coemcient transmission coefficient reflection time
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Generation and classification of the translational shape-invariant potentials based on the analytical transfer matrix method
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作者 桑明煌 余子星 +1 位作者 李翠翠 涂凯 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第12期52-56,共5页
For the conventional translational shape-invariant potentials (TSIPs), it has demonstrated that the phase contribution devoted by the scattered subwaves in the analytical transfer matrix quantization condition is in... For the conventional translational shape-invariant potentials (TSIPs), it has demonstrated that the phase contribution devoted by the scattered subwaves in the analytical transfer matrix quantization condition is integrable and independent of n. Based on this fact we propose a novel strategy to generate the whole set of conventional TSIPs and classify them into three types. The generating functions are given explicitly and the Morse potential is taken as an example to illustrate this strategy. 展开更多
关键词 translational shape-invariant potentials supersymmetric quantum mechanics analyticaltransfer matrix method scattered subwaves generating function
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Methods for Derivation of Density Matrix of Arbitrary Multi-Mode Gaussian States from Its Phase Space Representation
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作者 Sheng-Li Zhang Song Yang 《Chinese Physics Letters》 SCIE CAS CSCD 2019年第9期5-9,共5页
We present a method for derivation of the density matrix of an arbitrary multi-mode continuous variable Gaussian entangled state from its phase space representation.An explicit computer algorithm is given to reconstru... We present a method for derivation of the density matrix of an arbitrary multi-mode continuous variable Gaussian entangled state from its phase space representation.An explicit computer algorithm is given to reconstruct the density matrix from Gaussian covariance matrix and quadrature average values.As an example,we apply our method to the derivation of three-mode symmetric continuous variable entangled state.Our method can be used to analyze the entanglement and correlation in continuous variable quantum network with multi-mode quantum entanglement states. 展开更多
关键词 GAUSSIAN matrix methodS for DERIVATION of Density matrix of ARBITRARY MULTI-MODE GAUSSIAN States from Its Phase Space Representation
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The Consistency of the Solutions by T-Matrix Method with Canonical Solutions
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作者 朱峰 《Journal of Modern Transportation》 1998年第2期35-38,共4页
In this paper, the limitation of T matrix structure is analyzed. It is found that a solution by T matrix method can be transformed to a canonical solution when the boundary of the scatterer tends to the cylindrical ... In this paper, the limitation of T matrix structure is analyzed. It is found that a solution by T matrix method can be transformed to a canonical solution when the boundary of the scatterer tends to the cylindrical form and the scatterer is illuminated by E plane waves. It is concluded that a T matrix is diagonal with the scatter boundary in this limit situation. This is also the best result of numerical solution. 展开更多
关键词 T matrix method limitation transform canonical solution
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Mixed Least Square Method for Priority of Complementary Judgement Matrix and Its Algorithm
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作者 周宏安 刘三阳 《Journal of Southwest Jiaotong University(English Edition)》 2007年第1期75-79,共5页
Based on the concept of multiplicative fuzzy consistent complementary judgement matrix, the mixed least square method (MLSM) for priority of complementary judgement matrix is proposed and proved. Then, the correspon... Based on the concept of multiplicative fuzzy consistent complementary judgement matrix, the mixed least square method (MLSM) for priority of complementary judgement matrix is proposed and proved. Then, the corresponding convergent iterative algorithm is given and its convergence is proved. Finally, some main properties of the developed priority method, such as rank preservation under strong condition, etc., ate introduced. The theoretical analyses show that the MLSM can sufficiently reflect the preference information of the decision maker, and is easy to realize on a computer. 展开更多
关键词 Multi-objective decision-making Fuzzy complementary judgement matrix CONSISTENCY Mixed least square method PRIORITY
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Dynamic characteristics of a WPC-comparison of transfer matrix method and FE method
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作者 CHEN Guo-long and ME Wu School of Shipbuilding Engineering , Harbin Engineering University, Harbin 150001 , China 《Journal of Marine Science and Application》 2003年第2期25-30,共6页
To find the difference in dynamic characteristics between conventional monohull ship and wave penetrating catamaran (WPC), a WPC was taken as an object; its dynamic characteristics were computed by transfer matrix met... To find the difference in dynamic characteristics between conventional monohull ship and wave penetrating catamaran (WPC), a WPC was taken as an object; its dynamic characteristics were computed by transfer matrix method and finite element method respectively. According to the comparison of the nature frequency results and mode shape results, the fact that FEM method is more suitable to dynamic characteristics analysis of a WPC was pointed out, special features on dynamic characteristics of WPC were given, and some beneficial suggestions are proposed to optimize the strength of a WPC in design period. 展开更多
关键词 Wave penetrating catamaran Dynamic characteristics Transfer matrix method FEM.
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Electron impact excitation of Ni-like gold studied by Dirac R-matrix method
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作者 范全平 汪文慧 +4 位作者 胡峰 曹磊峰 张强强 刘钰薇 蒋刚 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第11期261-267,共7页
We calculate the electron impact excitation of Ni-like gold by using the Dirac R-matrix theory, and the cor- responding collision strengths and effective collision strengths are obtained. In the calculations of the le... We calculate the electron impact excitation of Ni-like gold by using the Dirac R-matrix theory, and the cor- responding collision strengths and effective collision strengths are obtained. In the calculations of the level energy, (1sZ2sZ2p6)3sZ3p63d10, 3s23p63d94/, 3s23p53d104/, and 3s3p63d104/(l = 0, 1,2,3) configurations are included and 107 fine-structure levels are generated. In the calculations of the collision strengths, only the first 59 levels are included. Com- parisons are made with the distorted wave (DW) results of Zeng et al. for both collision strengths and effective collision strengths. For the collision strengths, the two sets of calculations are in excellent agreement for most of the transitions. However, because of the inclusion of the resonances, our effective collision strengths are generally several times larger than those of Zeng et al.. The accuracy of our calculations is assessed. 展开更多
关键词 electron impact excitation R-matrix method Ni-like gold
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A Vicious Script in HTML Detection Method Using Judgment Matrix Approach
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作者 李志勇 张昊 +1 位作者 陶然 杜华 《Defence Technology(防务技术)》 SCIE EI CAS 2009年第1期76-80,共5页
A vicious script detection method based on statistic is proposed by analyzing the vicious script in the hypertext markup language(HTML).We utilize the judgment matrix approach which is one of the subjective weighting ... A vicious script detection method based on statistic is proposed by analyzing the vicious script in the hypertext markup language(HTML).We utilize the judgment matrix approach which is one of the subjective weighting approaches to set the different weights for various statistic methods.Then we make use of the weighted geometric method to perfect the statistic results.Experimental results show the validity of this method. 展开更多
关键词 判断矩阵 HTML 脚本 恶性 检测 超文本标记语言 统计分析 加权方法
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