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An Efficient Local Radial Basis Function Method for Image Segmentation Based on the Chan-Vese Model
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作者 Shupeng Qiu Chujin Lin Wei Zhao 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第4期1119-1134,共16页
In this paper,we consider the Chan–Vese(C-V)model for image segmentation and obtain its numerical solution accurately and efficiently.For this purpose,we present a local radial basis function method based on a Gaussi... In this paper,we consider the Chan–Vese(C-V)model for image segmentation and obtain its numerical solution accurately and efficiently.For this purpose,we present a local radial basis function method based on a Gaussian kernel(GA-LRBF)for spatial discretization.Compared to the standard radial basis functionmethod,this approach consumes less CPU time and maintains good stability because it uses only a small subset of points in the whole computational domain.Additionally,since the Gaussian function has the property of dimensional separation,the GA-LRBF method is suitable for dealing with isotropic images.Finally,a numerical scheme that couples GA-LRBF with the fourth-order Runge–Kutta method is applied to the C-V model,and a comparison of some numerical results demonstrates that this scheme achieves much more reliable image segmentation. 展开更多
关键词 Image segmentation Chan–Vese model local radial basis functionmethod Gaussian kernel Runge–Kuttamethod
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Novel Parameter Identification Method for Basis Weight Control Loop of Papermaking Process 被引量:1
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作者 Yunzhu Shen Wei Tang Yungang Liu 《Paper And Biomaterials》 CAS 2023年第1期35-49,共15页
The basis weight control loop of the papermaking process is a non-linear system with time-delay and time-varying.It is impractical to identify a model that can restore the model of real papermaking process.Determining... The basis weight control loop of the papermaking process is a non-linear system with time-delay and time-varying.It is impractical to identify a model that can restore the model of real papermaking process.Determining a more accurate identification model is very important for designing the controller of the control system and maintaining the stable operation of the papermaking process.In this study,a strange nonchaotic particle swarm optimization(SNPSO)algorithm is proposed to identify the models of real papermaking processes,and this identification ability is significantly enhanced compared with particle swarm optimization(PSO).First,random particles are initialized by strange nonchaotic sequences to obtain high-quality solutions.Furthermore,the weight of linear attenuation is replaced by strange nonchaotic sequence and the time-varying acceleration coefficients and a mutation rule with strange nonchaotic characteristics are utilized in SNPSO.The above strategies effectively improve the global and local search ability of particles and the ability to escape from local optimization.To illustrate the effectiveness of SNPSO,step response data are used to identify the models of real industrial processes.Compared with classical PSO,PSO with timevarying acceleration coefficients(PSO-TVAC)and modified particle swarm optimization(MPSO),the simulation results demonstrate that SNPSO has stronger identification ability,faster convergence speed,and better robustness. 展开更多
关键词 basis weight control system PAPERMAKING system identification particle swarm optimization strange nonchaotic sequence
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Metric Basis of Four-Dimensional Klein Bottle
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作者 Ali N.A.Koam Ali Ahmad +2 位作者 Maryam Salem Alatawi Muhammad Azeem Muhammad Faisal Nadeem 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第9期3011-3024,共14页
The Metric of a graph plays an essential role in the arrangement of different dimensional structures and finding their basis in various terms.The metric dimension of a graph is the selection of the minimum possible nu... The Metric of a graph plays an essential role in the arrangement of different dimensional structures and finding their basis in various terms.The metric dimension of a graph is the selection of the minimum possible number of vertices so that each vertex of the graph is distinctively defined by its vector of distances to the set of selected vertices.This set of selected vertices is known as the metric basis of a graph.In applied mathematics or computer science,the topic of metric basis is considered as locating number or locating set,and it has applications in robot navigation and finding a beacon set of a computer network.Due to the vast applications of this concept in computer science,optimization problems,and also in chemistry enormous research has been conducted.To extend this research to a four-dimensional structure,we studied the metric basis of the Klein bottle and proved that the Klein bottle has a constant metric dimension for the variation of all its parameters.Although the metric basis is variying in 3 and 4 values when the values of its parameter change,it remains constant and unchanged concerning its order or number of vertices.The methodology of determining the metric basis or locating set is based on the distances of a graph.Therefore,we proved the main theorems in distance forms. 展开更多
关键词 Klein bottle metric basis resolving set metric dimension
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Basis functions for shallow-water temperature profiles based on the internal-wave eigenmodes
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作者 Qianqian Li Shoulian Cao +2 位作者 Yu Luo Kai Zhang Fanlin Yang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第2期56-64,共9页
The shallow-water temperature profile is typically parameterized using a few empirical orthogonal function(EOF)coefficients.However,when the experimental area is poorly known or highly variable,the adaptability of the... The shallow-water temperature profile is typically parameterized using a few empirical orthogonal function(EOF)coefficients.However,when the experimental area is poorly known or highly variable,the adaptability of the EOFs will be significantly reduced.In this study,a new set of basis functions,generated by combining the internal-wave eigenmodes with the average temperature gradient,is developed for characterizing the temperature perturbations.Temperature profiles recorded by a thermistor chain in the South China Sea in 2015 are processed and analyzed.Compared to the EOFs,the new set of basis functions has higher reconstruction accuracy and adaptability;it is also more stable in ocean regions that have internal waves. 展开更多
关键词 temperature profile basis function internal-wave eigenmode EOF sound speed profile
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The Class of Atomic Exponential Basis Functions EFup_(n)(x,ω)-Development and Application
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作者 Nives Brajcic Kurbasa Blaz Gotovac Vedrana Kozulic 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第4期65-90,共26页
The purpose of this paper is to present the class of atomic basis functions(ABFs)which are of exponential type and are denoted by EFupn(x,ω).While ABFs of the algebraic type are already represented in the numerical m... The purpose of this paper is to present the class of atomic basis functions(ABFs)which are of exponential type and are denoted by EFupn(x,ω).While ABFs of the algebraic type are already represented in the numerical modeling of various problems inmathematical physics and computationalmechanics,ABFs of the exponential type have not yet been sufficiently researched.These functions,unlike the ABFs of the algebraic type Fupn(x),contain the tension parameterω,which gives them additional approximation properties.Exponential monomials up to the nth degree can be described exactly by the linear combination of the functions EFupn(x,ω).The function EFupn for n=0 is called the“mother”ABF of the exponential type,i.e.,EFup0(x,ω)≡Eup(x,ω).In other words,the functions EFupn(x,ω)are elements of the linear vector space EUPn and retain all the properties of their“mother”function Eup(x,ω).Thus,this paper,in terms of its content and purpose,can be understood as a sequel of the article by Brajcic Kurbasa et al.,which shows the basic properties and application of the basis function Eup(x,ω).This paper presents,in an analogous way,the development and application of the exponential basis functions EFupn(x,ω).Here,for the first time,expressions for calculating the values of the functions EFupn(x,ω)and their derivatives are given in a form suitable for application in numerical analyses,which is shown in the verification examples of the approximations of known functions. 展开更多
关键词 Exponential atomic basis functions Fourier transform compact support tension parameter
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Radial Basis Approximations Based BEMD for Enhancement of Non-Uniform Illumination Images
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作者 Anchal Tyagi Salem Alelyani +3 位作者 Sapna Katiyar Mohammad Rashid Hussain Rijwan Khan Mohammed Saleh Alsaqer 《Computer Systems Science & Engineering》 SCIE EI 2023年第5期1423-1438,共16页
An image can be degraded due to many environmental factors like foggy or hazy weather,low light conditions,extra light conditions etc.Image captured under the poor light conditions is generally known as non-uniform il... An image can be degraded due to many environmental factors like foggy or hazy weather,low light conditions,extra light conditions etc.Image captured under the poor light conditions is generally known as non-uniform illumination image.Non-uniform illumination hides some important information present in an image during the image capture Also,it degrades the visual quality of image which generates the need for enhancement of such images.Various techniques have been present in literature for the enhancement of such type of images.In this paper,a novel architecture has been proposed for enhancement of poor illumination images which uses radial basis approximations based BEMD(Bi-dimensional Empirical Mode Decomposition).The enhancement algorithm is applied on intensity and saturation components of image.Firstly,intensity component has been decomposed into various bi-dimensional intrinsic mode function and residue by using sifting algorithm.Secondly,some linear transformations techniques have been applied on various bidimensional intrinsic modes obtained and residue and further on joining the transformed modes with residue,enhanced intensity component is obtained.Saturation part of an image is then enhanced in accordance to the enhanced intensity component.Final enhanced image can be obtained by joining the hue,enhanced intensity and enhanced saturation parts of the given image.The proposed algorithm will not only give the visual pleasant image but maintains the naturalness of image also. 展开更多
关键词 Non-uniform illumination BEMD intrinsic modes radial basis approximation linear transformation
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A SUPERLINEARLY CONVERGENT SPLITTING FEASIBLE SEQUENTIAL QUADRATIC OPTIMIZATION METHOD FOR TWO-BLOCK LARGE-SCALE SMOOTH OPTIMIZATION
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作者 简金宝 张晨 刘鹏杰 《Acta Mathematica Scientia》 SCIE CSCD 2023年第1期1-24,共24页
This paper discusses the two-block large-scale nonconvex optimization problem with general linear constraints.Based on the ideas of splitting and sequential quadratic optimization(SQO),a new feasible descent method fo... This paper discusses the two-block large-scale nonconvex optimization problem with general linear constraints.Based on the ideas of splitting and sequential quadratic optimization(SQO),a new feasible descent method for the discussed problem is proposed.First,we consider the problem of quadratic optimal(QO)approximation associated with the current feasible iteration point,and we split the QO into two small-scale QOs which can be solved in parallel.Second,a feasible descent direction for the problem is obtained and a new SQO-type method is proposed,namely,splitting feasible SQO(SF-SQO)method.Moreover,under suitable conditions,we analyse the global convergence,strong convergence and rate of superlinear convergence of the SF-SQO method.Finally,preliminary numerical experiments regarding the economic dispatch of a power system are carried out,and these show that the SF-SQO method is promising. 展开更多
关键词 large scale optimization two-block smooth optimization splitting method feasible sequential quadratic optimization method superlinear convergence
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New Approach to Find Initial Basic Feasible Solution (IBFS) for Optimal Solution in Transportation Problem
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作者 Shubham Raval 《Open Journal of Applied Sciences》 CAS 2023年第2期207-211,共5页
Minimizing transportation time and getting optimal solutions are always considered as important factors while solving transportation problem. This paper shows a new approach for finding initial basic solution for tran... Minimizing transportation time and getting optimal solutions are always considered as important factors while solving transportation problem. This paper shows a new approach for finding initial basic solution for transportation problem which reduces cost of transportation more than any transportation method such as LCM, northwest, Vogel’s approximation and so on. This method has been illustrated by taking an example;afterwards, it compares basic initial feasible solution with other methods IBF and optimal dictate solutions such as MODI and Steppingstone method. 展开更多
关键词 Transportation Problem New Approach for Transportation Problem Initial Basic feasible Solution Minimizing Transportation Time
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An Update Method of Decision Implication Canonical Basis on Attribute Granulating
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作者 Yanhui Zhai Rujie Chen Deyu Li 《Intelligent Automation & Soft Computing》 SCIE 2023年第8期1833-1851,共19页
Decision implication is a form of decision knowledge represen-tation,which is able to avoid generating attribute implications that occur between condition attributes and between decision attributes.Compared with other... Decision implication is a form of decision knowledge represen-tation,which is able to avoid generating attribute implications that occur between condition attributes and between decision attributes.Compared with other forms of decision knowledge representation,decision implication has a stronger knowledge representation capability.Attribute granularization may facilitate the knowledge extraction of different attribute granularity layers and thus is of application significance.Decision implication canonical basis(DICB)is the most compact set of decision implications,which can efficiently represent all knowledge in the decision context.In order to mine all deci-sion information on decision context under attribute granulating,this paper proposes an updated method of DICB.To this end,the paper reduces the update of DICB to the updates of decision premises after deleting an attribute and after adding granulation attributes of some attributes.Based on this,the paper analyzes the changes of decision premises,examines the properties of decision premises,designs an algorithm for incrementally generating DICB,and verifies its effectiveness through experiments.In real life,by using the updated algorithm of DICB,users may obtain all decision knowledge on decision context after attribute granularization. 展开更多
关键词 Decision context attribute granulating decision implication decision implication canonical basis
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Crack Fault Diagnosis and Location Method for a Dual-Disk Hollow Shaft Rotor System Based on the Radial Basis Function Network and Pattern Recognition Neural Network
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作者 Yuhong Jin Lei Hou +1 位作者 Zhenyong Lu Yushu Chen 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2023年第2期180-197,共18页
The crack fault is one of the most common faults in the rotor system,and researchers have paid close attention to its fault diagnosis.However,most studies focus on discussing the dynamic response characteristics cause... The crack fault is one of the most common faults in the rotor system,and researchers have paid close attention to its fault diagnosis.However,most studies focus on discussing the dynamic response characteristics caused by the crack rather than estimating the crack depth and position based on the obtained vibration signals.In this paper,a novel crack fault diagnosis and location method for a dual-disk hollow shaft rotor system based on the Radial basis function(RBF)network and Pattern recognition neural network(PRNN)is presented.Firstly,a rotor system model with a breathing crack suitable for a short-thick hollow shaft rotor is established based on the finite element method,where the crack's periodic opening and closing pattern and different degrees of crack depth are considered.Then,the dynamic response is obtained by the harmonic balance method.By adjusting the crack parameters,the dynamic characteristics related to the crack depth and position are analyzed through the amplitude-frequency responses and waterfall plots.The analysis results show that the first critical speed,first subcritical speed,first critical speed amplitude,and super-harmonic resonance peak at the first subcritical speed can be utilized for the crack fault diagnosis.Based on this,the RBF network and PRNN are adopted to determine the depth and approximate location of the crack respectively by taking the above dynamic characteristics as input.Test results show that the proposed method has high fault diagnosis accuracy.This research proposes a crack detection method adequate for the hollow shaft rotor system,where the crack depth and position are both unknown. 展开更多
关键词 Hollow shaft rotor Breathing crack Radial basis function network Pattern recognition neural network Machine learning
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All-electron ZORA triple zeta basis sets for the elements Cs-La and Hf-Rn
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作者 Antônio Canal Neto Francisco E.Jorge Henrique R.Cda Cruz 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第9期242-249,共8页
Segmented all-electron basis set of triple zeta valence quality plus polarization functions(TZP)for the elements of the fifth row to be used together with the zero-order regular approximation(ZORA)is carefully constru... Segmented all-electron basis set of triple zeta valence quality plus polarization functions(TZP)for the elements of the fifth row to be used together with the zero-order regular approximation(ZORA)is carefully constructed.To correctly describe electrons distant from atomic nuclei,the basis set is augmented with diffuse functions giving rise to a set designated as ATZP-ZORA.At the ZORA-B3LYP theoretical level,these sets are used to calculate the ionization energy and mean dipole polarizability of some atoms,bond length,dissociation energy,and harmonic vibrational frequency of diatomic molecules.Then,these results are compared with the theoretical and experimental data found in the literature.Even considering that our sets are relatively compact,they are sufficiently accurate and reliable to perform property calculations involving simultaneously electrons from the inner shell and outer shell.The performances of the ZORA and second-order Douglas-Kroll-Hess Hamiltonians are evaluated and the results are also discussed. 展开更多
关键词 TZP-ZORA and ATZP-ZORA basis sets ZORA-B3LYP method Cs-La and Hf-Rn elements atomic and molecular properties
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Local Radial Basis Function Methods: Comparison, Improvements, and Implementation
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作者 Scott A. Sarra 《Journal of Applied Mathematics and Physics》 2023年第12期3867-3886,共20页
Radial Basis Function methods for scattered data interpolation and for the numerical solution of PDEs were originally implemented in a global manner. Subsequently, it was realized that the methods could be implemented... Radial Basis Function methods for scattered data interpolation and for the numerical solution of PDEs were originally implemented in a global manner. Subsequently, it was realized that the methods could be implemented more efficiently in a local manner and that the local approaches could match or even surpass the accuracy of the global implementations. In this work, three localization approaches are compared: a local RBF method, a partition of unity method, and a recently introduced modified partition of unity method. A simple shape parameter selection method is introduced and the application of artificial viscosity to stabilize each of the local methods when approximating time-dependent PDEs is reviewed. Additionally, a new type of quasi-random center is introduced which may be better choices than other quasi-random points that are commonly used with RBF methods. All the results within the manuscript are reproducible as they are included as examples in the freely available Python Radial Basis Function Toolbox. 展开更多
关键词 Radial basis Functions Shape Parameter Selection Quasi-Random Centers Numerical PDEs Scientific Computing Open Source Software Python Programming Language Reproducible Research
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A Novel Radial Basis Function Neural Network Approach for ECG Signal Classification
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作者 S.Sathishkumar R.Devi Priya 《Intelligent Automation & Soft Computing》 SCIE 2023年第1期129-148,共20页
ions in the ECG signal.The cardiologist and medical specialistfind numerous difficulties in the process of traditional approaches.The specified restrictions are eliminated in the proposed classifier.The fundamental ai... ions in the ECG signal.The cardiologist and medical specialistfind numerous difficulties in the process of traditional approaches.The specified restrictions are eliminated in the proposed classifier.The fundamental aim of this work is tofind the R-R interval.To analyze the blockage,different approaches are implemented,which make the computation as facile with high accuracy.The information are recovered from the MIT-BIH dataset.The retrieved data contain normal and pathological ECG signals.To obtain a noiseless signal,Gaborfilter is employed and to compute the amplitude of the signal,DCT-DOST(Discrete cosine based Discrete orthogonal stock well transform)is implemented.The amplitude is computed to detect the cardiac abnormality.The R peak of the underlying ECG signal is noted and the segment length of the ECG cycle is identified.The Genetic algorithm(GA)retrieves the primary highlights and the classifier integrates the data with the chosen attributes to optimize the identification.In addition,the GA helps in performing hereditary calculations to reduce the problem of multi-target enhancement.Finally,the RBFNN(Radial basis function neural network)is applied,which diminishes the local minima present in the signal.It shows enhancement in characterizing the ordinary and anomalous ECG signals. 展开更多
关键词 Electrocardiogram signal gaborfilter discrete cosine based discrete orthogonal stock well transform genetic algorithm radial basis function neural network
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Galerkin Method for Numerical Solution of Volterra Integro-Differential Equations with Certain Orthogonal Basis Function
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作者 Omotayo Adebayo Taiwo Liman Kibokun Alhassan +1 位作者 Olutunde Samuel Odetunde Olatayo Olusegun Alabi 《International Journal of Modern Nonlinear Theory and Application》 2023年第2期68-80,共13页
This paper concerns the implementation of the orthogonal polynomials using the Galerkin method for solving Volterra integro-differential and Fredholm integro-differential equations. The constructed orthogonal polynomi... This paper concerns the implementation of the orthogonal polynomials using the Galerkin method for solving Volterra integro-differential and Fredholm integro-differential equations. The constructed orthogonal polynomials are used as basis functions in the assumed solution employed. Numerical examples for some selected problems are provided and the results obtained show that the Galerkin method with orthogonal polynomials as basis functions performed creditably well in terms of absolute errors obtained. 展开更多
关键词 Galerkin Method Integro-Differential Equation Orthogonal Polynomials basis Function Approximate Solution
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Evolution Performance of Symbolic Radial Basis Function Neural Network by Using Evolutionary Algorithms
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作者 Shehab Abdulhabib Alzaeemi Kim Gaik Tay +2 位作者 Audrey Huong Saratha Sathasivam Majid Khan bin Majahar Ali 《Computer Systems Science & Engineering》 SCIE EI 2023年第10期1163-1184,共22页
Radial Basis Function Neural Network(RBFNN)ensembles have long suffered from non-efficient training,where incorrect parameter settings can be computationally disastrous.This paper examines different evolutionary algor... Radial Basis Function Neural Network(RBFNN)ensembles have long suffered from non-efficient training,where incorrect parameter settings can be computationally disastrous.This paper examines different evolutionary algorithms for training the Symbolic Radial Basis Function Neural Network(SRBFNN)through the behavior’s integration of satisfiability programming.Inspired by evolutionary algorithms,which can iteratively find the nearoptimal solution,different Evolutionary Algorithms(EAs)were designed to optimize the producer output weight of the SRBFNN that corresponds to the embedded logic programming 2Satisfiability representation(SRBFNN-2SAT).The SRBFNN’s objective function that corresponds to Satisfiability logic programming can be minimized by different algorithms,including Genetic Algorithm(GA),Evolution Strategy Algorithm(ES),Differential Evolution Algorithm(DE),and Evolutionary Programming Algorithm(EP).Each of these methods is presented in the steps in the flowchart form which can be used for its straightforward implementation in any programming language.With the use of SRBFNN-2SAT,a training method based on these algorithms has been presented,then training has been compared among algorithms,which were applied in Microsoft Visual C++software using multiple metrics of performance,including Mean Absolute Relative Error(MARE),Root Mean Square Error(RMSE),Mean Absolute Percentage Error(MAPE),Mean Bias Error(MBE),Systematic Error(SD),Schwarz Bayesian Criterion(SBC),and Central Process Unit time(CPU time).Based on the results,the EP algorithm achieved a higher training rate and simple structure compared with the rest of the algorithms.It has been confirmed that the EP algorithm is quite effective in training and obtaining the best output weight,accompanied by the slightest iteration error,which minimizes the objective function of SRBFNN-2SAT. 展开更多
关键词 Satisfiability logic programming symbolic radial basis function neural network evolutionary programming algorithm genetic algorithm evolution strategy algorithm differential evolution algorithm
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A Numerical Method for Solving Ill-Conditioned Equation Systems Arising from Radial Basis Functions
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作者 Edward J. Kansa 《American Journal of Computational Mathematics》 2023年第2期356-370,共15页
Continuously differentiable radial basis functions (C<sup>∞</sup>-RBFs), while being theoretically exponentially convergent are considered impractical computationally because the coefficient matrices are ... Continuously differentiable radial basis functions (C<sup>∞</sup>-RBFs), while being theoretically exponentially convergent are considered impractical computationally because the coefficient matrices are full and can become very ill- conditioned. Similarly, the Hilbert and Vandermonde have full matrices and become ill-conditioned. The difference between a coefficient matrix generated by C<sup>∞</sup>-RBFs for partial differential or integral equations and Hilbert and Vandermonde systems is that C<sup>∞</sup>-RBFs are very sensitive to small changes in the adjustable parameters. These parameters affect the condition number and solution accuracy. The error terrain has many local and global maxima and minima. To find stable and accurate numerical solutions for full linear equation systems, this study proposes a hybrid combination of block Gaussian elimination (BGE) combined with arbitrary precision arithmetic (APA) to minimize the accumulation of rounding errors. In the future, this algorithm can execute faster using preconditioners and implemented on massively parallel computers. 展开更多
关键词 Continuously Differentiable Radial basis Functions Global Maxima and Minima Solutions of Ill-Conditioned Linear Equations Block Gaussian Elimination Arbitrary Precision Arithmetic
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冠心病心血瘀阻证大鼠心肌组织代谢组学研究 被引量:1
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作者 李静 郭志华 +5 位作者 刘建和 钟森杰 匡慧芳 杨漾 刘祎 张秋雁 《中国中医药信息杂志》 CAS CSCD 2024年第3期119-126,共8页
目的研究冠心病心血瘀阻证大鼠心肌组织代谢产物谱,探讨其病证生物学基础。方法SD大鼠随机分为假手术组和模型组,采用冠状动脉左前降支结扎法制备冠心病心血瘀阻证大鼠模型,观察大鼠一般状态,检测舌象色度、心电图、心功能,HE染色、透... 目的研究冠心病心血瘀阻证大鼠心肌组织代谢产物谱,探讨其病证生物学基础。方法SD大鼠随机分为假手术组和模型组,采用冠状动脉左前降支结扎法制备冠心病心血瘀阻证大鼠模型,观察大鼠一般状态,检测舌象色度、心电图、心功能,HE染色、透射电镜观察心肌组织形态及超微结构,用超高效液相色谱-质谱技术检测心肌组织差异代谢物,并对代谢通路进行富集分析。结果与假手术组比较,模型组大鼠舌象色度R、G、B值均显著降低(P<0.05),心电图心率、ST段抬高幅度显著上升(P<0.05),左室射血分数、左室短轴缩短率显著下降(P<0.05),左室收缩末期内径、左室舒张末期内径显著上升(P<0.05);心肌组织结构模糊,有炎性细胞浸润,线粒体肿胀、破裂、溶解,嵴结构断裂减少。代谢组学共鉴定出29个假手术组与模型组差异显著的潜在生物标志物(7个上调、22个下调),主要富集于硫胺素代谢,精氨酸生物合成,嘌呤代谢,氨酰基-tRNA生物合成,丙氨酸、天冬氨酸和谷氨酸代谢,戊糖和葡萄糖醛酸相互转化,糖酵解/糖异生,缬氨酸、亮氨酸和异亮氨酸降解,三羧酸循环,丙酮酸代谢10条代谢通路。结论冠状动脉左前降支结扎法可较好地模拟冠心病心血瘀证病理过程,其病理机制涉及葡萄糖代谢、线粒体能量代谢、氨基酸代谢、蛋白质生物合成、嘌呤代谢等多层次代谢网络紊乱。 展开更多
关键词 冠心病 心血瘀阻证 生物学基础 代谢组学 大鼠
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三类低复杂度基及其对偶基
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作者 张妍 苏丹丹 《辽宁师范大学学报(自然科学版)》 CAS 2024年第1期21-28,共8页
设N={α_(0),α_(1),…,α_(n-1)}是E在F上的一组基,构造了一类给定乘法表及复杂度为3n-2的低复杂度正规基,根据迹函数和乘法表的相关概念,证明其对偶基M的生成元的形式,并证明了对偶基的复杂度为3n-2或3n-3.计算了E在F上的伪自对偶多... 设N={α_(0),α_(1),…,α_(n-1)}是E在F上的一组基,构造了一类给定乘法表及复杂度为3n-2的低复杂度正规基,根据迹函数和乘法表的相关概念,证明其对偶基M的生成元的形式,并证明了对偶基的复杂度为3n-2或3n-3.计算了E在F上的伪自对偶多项式基和弱自对偶多项式基的复杂度.为密码学领域寻找优化的算法,选择合适的基提供了理论依据. 展开更多
关键词 正规基 多项式基 对偶基 复杂度
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互动语言学在汉语二语教学中的应用:理论基础与实践设计 被引量:1
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作者 姚双云 王杰 《华文教学与研究》 2024年第1期10-16,25,共8页
二语教学是互动语言学极有发展前景的一个研究领域。本文简要阐述了将互动语言学应用于汉语二语教学的理论基础,并结合已有研究提出互动视角下汉语二语教学实践设计的基本思路。总体来看,互动语言学能应用于汉语二语教学有三个重要的理... 二语教学是互动语言学极有发展前景的一个研究领域。本文简要阐述了将互动语言学应用于汉语二语教学的理论基础,并结合已有研究提出互动视角下汉语二语教学实践设计的基本思路。总体来看,互动语言学能应用于汉语二语教学有三个重要的理论基础:1)二语发展以言谈互动为原始环境;2)二语习得以互动能力为终极目标;3)二语能力以社会行为表达为核心要素。在此基础上,文章提出汉语二语教学实践四点基本思路:1)开发真实自然的汉语教材;2)创设面向交际的互动语境;3)运用基于互动的教学策略;4)开发多种模态的教学资源。 展开更多
关键词 互动语言学 汉语二语教学 理论基础 实践设计
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基于HPLC-Q-Exactive Orbitrap MS/MS整合网络药理学研究衢枳壳降糖的物质基础及作用机制
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作者 姜莉苑 董馨 +5 位作者 田雨欣 宋剑锋 赵维良 胡颖菲 李梦盈 冯敬骞 《中国中医基础医学杂志》 CAS CSCD 2024年第3期461-467,共7页
目的以入血成分为研究对象,基于网络药理学探究衢枳壳对糖尿病起效的物质基础及作用机制。方法采用高效液相色谱串联四极杆-静电场轨道阱高分辨质谱(high-performance liquid chromatography tandem quadrupole-electrostatic field orb... 目的以入血成分为研究对象,基于网络药理学探究衢枳壳对糖尿病起效的物质基础及作用机制。方法采用高效液相色谱串联四极杆-静电场轨道阱高分辨质谱(high-performance liquid chromatography tandem quadrupole-electrostatic field orbitrap high resolution mass spectrometry,HPLC-Q-Exactive Orbitrap MS/MS)对衢枳壳入血成分进行鉴定,在此基础上通过Swiss Target Prediction与SuperPred数据库预测入血成分作用靶点,同时在OMIM,GeneCards等数据库获取糖尿病靶点。采用Cytoscape 3.9.1绘制中药衢枳壳“活性成分-靶点-疾病”网络关系图,利用String数据分析平台进行蛋白互作(protein-protein interaction,PPI)网络分析,筛选关键靶点。通过DAVID数据库对关键靶点进行基因本体功能(gene ontology,GO)和京都基因与基因组百科全书(kyoto encyclopedia of genes and genomes,KEGG)通路富集分析。应用Autodock 1.5.7软件进行分子对接验证。结果共鉴定衢枳壳入血成分20个,筛选出潜在靶点170个,核心靶点32个。GO功能富集和KEGG信号通路分析结果显示缺氧诱导因子(hypoxia-inducible factor,HIF)-1信号通路、晚期糖基化终末产物(advanced glycation end products,AGE)-晚期糖基化终产物受体(receptor for advanced glycation end products,RAGE)信号通路、表皮生长因子(epidermal growth factor receptor,EGFR)信号通路、癌症蛋白聚糖通路等为衢枳壳降糖的关键通路,丝氨酸/苏氨酸蛋白激酶(RAC serine/threonine-protein kinase,AKT)1、白蛋白(albumin,ALB)、细胞肿瘤抗原p53(cellular tumor antigenp 53,TP53)、肿瘤坏死因子(tumor necrosis factor,TNF)、EGFR为其中关键靶点,且衢枳壳中5个活性成分与核心靶点经分子对接后的结合活性较好。结论衢枳壳中的芦丁、新橙皮苷、橙皮苷、芸香柚皮苷、川陈皮素等可能为衢枳壳降糖的物质基础,可能是通过调控HIF-1、AGE-RAGE、EGFR等信号通路及AKT1、ALB、TP53等核心基因发挥降糖作用。 展开更多
关键词 衢枳壳 糖尿病 网络药理学 物质基础 作用机制
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