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Brain Functional Network Generation Using Distribution-Regularized Adversarial Graph Autoencoder with Transformer for Dementia Diagnosis
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作者 Qiankun Zuo Junhua Hu +5 位作者 Yudong Zhang Junren Pan Changhong Jing Xuhang Chen Xiaobo Meng Jin Hong 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第12期2129-2147,共19页
The topological connectivity information derived from the brain functional network can bring new insights for diagnosing and analyzing dementia disorders.The brain functional network is suitable to bridge the correlat... The topological connectivity information derived from the brain functional network can bring new insights for diagnosing and analyzing dementia disorders.The brain functional network is suitable to bridge the correlation between abnormal connectivities and dementia disorders.However,it is challenging to access considerable amounts of brain functional network data,which hinders the widespread application of data-driven models in dementia diagnosis.In this study,a novel distribution-regularized adversarial graph auto-Encoder(DAGAE)with transformer is proposed to generate new fake brain functional networks to augment the brain functional network dataset,improving the dementia diagnosis accuracy of data-driven models.Specifically,the label distribution is estimated to regularize the latent space learned by the graph encoder,which canmake the learning process stable and the learned representation robust.Also,the transformer generator is devised to map the node representations into node-to-node connections by exploring the long-term dependence of highly-correlated distant brain regions.The typical topological properties and discriminative features can be preserved entirely.Furthermore,the generated brain functional networks improve the prediction performance using different classifiers,which can be applied to analyze other cognitive diseases.Attempts on the Alzheimer’s Disease Neuroimaging Initiative(ADNI)dataset demonstrate that the proposed model can generate good brain functional networks.The classification results show adding generated data can achieve the best accuracy value of 85.33%,sensitivity value of 84.00%,specificity value of 86.67%.The proposed model also achieves superior performance compared with other related augmentedmodels.Overall,the proposedmodel effectively improves cognitive disease diagnosis by generating diverse brain functional networks. 展开更多
关键词 Adversarial graph encoder label distribution generative transformer functional brain connectivity graph convolutional network DEMENTIA
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Generating function of product of bivariate Hermite polynomials and their applications in studying quantum optical states 被引量:1
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作者 范洪义 张鹏飞 王震 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第5期204-209,共6页
By virtue of the operator-Hermite-polynomial method, we derive some new generating function formulas of the product of two bivariate Hermite polynomials. Their applications in studying quantum optical states are prese... By virtue of the operator-Hermite-polynomial method, we derive some new generating function formulas of the product of two bivariate Hermite polynomials. Their applications in studying quantum optical states are presented. 展开更多
关键词 operator-Hermite-polynomials (OHP) method generating function product of bivariate Hermite polynomials
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New generating function formulae of even- and odd-Hermite polynomials obtained and applied in the context of quantum optics 被引量:1
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作者 范洪义 展德会 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第6期18-22,共5页
By combining the operator Hermite polynomial method and the technique of integration within an ordered product of operators, for the first time we derive the generating function of even- and odd-Hermite polynomials wh... By combining the operator Hermite polynomial method and the technique of integration within an ordered product of operators, for the first time we derive the generating function of even- and odd-Hermite polynomials which will be useful in constructing new optical field states. We then show that the squeezed state and photon-added squeezed state can be expressed by even- and odd-Hermite polynomials. 展开更多
关键词 generating function even- and odd-Hermite polynomials Hermite polynomial method techniqueof integral within an ordered product of operators
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Some new generating function formulae of the two-variable Hermite polynomials and their application in quantum optics 被引量:1
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作者 展德会 范洪义 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第12期30-33,共4页
We derive some new generating function formulae of the two-variable Hermite polynomials, such as ∞∑n=0tm/m!Hn,2m(x),∞∑n=0sntm/n!m!H2n,2m(x,y),and ∞∑n=0sntm/n!m!H2n+l,2m+k(x,y).We employ the operator Herm... We derive some new generating function formulae of the two-variable Hermite polynomials, such as ∞∑n=0tm/m!Hn,2m(x),∞∑n=0sntm/n!m!H2n,2m(x,y),and ∞∑n=0sntm/n!m!H2n+l,2m+k(x,y).We employ the operator Hermite polynomial method and the technique of integration within an ordered product of operators to solve these problems, which will be useful in constructing new optical field states. 展开更多
关键词 generating function two-variable Hermite polynomials Hermite polynomial method technique of integral within an ordered product of operators
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A Set of Almost Automorphic Functions and Applications
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作者 William Dimbour Vincent Valmorin 《Applied Mathematics》 2024年第1期9-21,共13页
For a set S of real numbers, we introduce the concept of S-almost automorphic functions valued in a Banach space. It generalizes in particular the space of Z-almost automorphic functions. Considering the space of S-al... For a set S of real numbers, we introduce the concept of S-almost automorphic functions valued in a Banach space. It generalizes in particular the space of Z-almost automorphic functions. Considering the space of S-almost automorphic functions, we give sufficient conditions of the existence and uniqueness of almost automorphic solutions of a differential equation with a piecewise constant argument of generalized type. This is done using the Banach fixed point theorem. 展开更多
关键词 Almost Automorphic functions S-Almost Automorphic functions Differential Equation with Piecewise Constant Argument of generalized Type
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Free vibration and buckling analysis of polymeric composite beams reinforced by functionally graded bamboo fbers
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作者 H.M.FEIZABAD M.H.YAS 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第3期543-562,共20页
Natural fibers have been extensively researched as reinforcement materials in polymers on account of their environmental and economic advantages in comparison with synthetic fibers in the recent years.Bamboo fibers ar... Natural fibers have been extensively researched as reinforcement materials in polymers on account of their environmental and economic advantages in comparison with synthetic fibers in the recent years.Bamboo fibers are renowned for their good mechanical properties,abundance,and short cycle growth.As beams are one of the fundamental structural components and are susceptible to mechanical loads in engineering applications,this paper performs a study on the free vibration and buckling responses of bamboo fiber reinforced composite(BFRC)beams on the elastic foundation.Three different functionally graded(FG)layouts and a uniform one are the considered distributions for unidirectional long bamboo fibers across the thickness.The elastic properties of the composite are determined with the law of mixture.Employing Hamilton’s principle,the governing equations of motion are obtained.The generalized differential quadrature method(GDQM)is then applied to the equations to obtain the results.The achieved outcomes exhibit that the natural frequency and buckling load values vary as the fiber volume fractions and distributions,elastic foundation stiffness values,and boundary conditions(BCs)and slenderness ratio of the beam change.Furthermore,a comparative study is conducted between the derived analysis outcomes for BFRC and homogenous polymer beams to examine the effectiveness of bamboo fibers as reinforcement materials,demonstrating the significant enhancements in both vibration and buckling responses,with the exception of natural frequencies for cantilever beams on the Pasternak foundation with the FG-◇fiber distribution.Eventually,the obtained analysis results of BFRC beams are also compared with those for carbon nanotube reinforced composite(CNTRC)beams found in the literature,indicating that the buckling loads and natural frequencies of BFRC beams are lower than those of CNTRC beams. 展开更多
关键词 bamboo fiber free vibration buckling analysis functionally graded(FG)beam elastic foundation generalized differential quadrature method(GDQM)
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Generating functions for powers of second-order recurrence sequences
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作者 王晓霞 李梅 《Journal of Shanghai University(English Edition)》 CAS 2011年第6期517-521,共5页
For the sequences satisfying the recurrence relation of the second order,the generating functions for the products of the powers of these sequences are established.This study was from Carlita and Riordan who began a s... For the sequences satisfying the recurrence relation of the second order,the generating functions for the products of the powers of these sequences are established.This study was from Carlita and Riordan who began a study on closed form of generating functions for powers of second-order recurrence sequences.This investigation was completed by Stnica.Inspired by the recent work of Istva'n about the non-closed generating functions of the products of the powers of the second-order sequences,the authors give several extensions of Istva'n's results in this paper. 展开更多
关键词 generating function second-order sequence the Binet formula
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STUDY ON STREAM CIPHERS USING GENERATING FUNCTIONS
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作者 武传坤 《Journal of Electronics(China)》 1993年第1期34-40,共7页
Several kinds of stream ciphers—complementary sequences of period sequences,partial sum of period sequences,inverse order sequences and finitely generated sequences,arestudied by using techniques of generating functi... Several kinds of stream ciphers—complementary sequences of period sequences,partial sum of period sequences,inverse order sequences and finitely generated sequences,arestudied by using techniques of generating functions.Their minimal polynomials,periods,as wellas generating functions are given.As to finitely generated sequences,the change of their linearcomplexity profiles as well as the relationship between the two generated sequences usder thecase in which the degree of connected polynomials are fixed,are discussed. 展开更多
关键词 STREAM CIPHER generating function Complementery SEQUENCE Partial SUM SEQUENCE INVERSE Order SEQUENCE Finitely generated SEQUENCE B-M Algorithm
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Test of Generating Function and Estimation of Equivalent Radius in Some Weapon Systems and Its Stochastic Simulation
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作者 Famei Zheng 《Applied Mathematics》 2011年第12期1546-1550,共5页
We discuss three-dimensional uniform distribution and its property in a sphere;give a method of assessing the tactical and technical indices of cartridge ejection uniformity in some type of weapon systems. Meanwhile w... We discuss three-dimensional uniform distribution and its property in a sphere;give a method of assessing the tactical and technical indices of cartridge ejection uniformity in some type of weapon systems. Meanwhile we obtain the test of generating function and the estimation of equivalent radius. The uniformity of distribution is tested and verified with ω2 test method on the basis of stochastic simulation example. 展开更多
关键词 UNIFORM Distribution in a SPHERE WEAPON Systems generating function EQUIVALENT RADIUS Stochastic Simulation
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Quantum fields presentation and generating functions of symplectic Schur functions and symplectic universal characters
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作者 李登慧 王菲 颜昭雯 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第8期197-206,共10页
This paper is concerned with construction of quantum fields presentation and generating functions of symplectic Schur functions and symplectic universal characters.The boson-fermion correspondence for these symmetric ... This paper is concerned with construction of quantum fields presentation and generating functions of symplectic Schur functions and symplectic universal characters.The boson-fermion correspondence for these symmetric functions have been presented.In virtue of quantum fields,we derive a series of infinite order nonlinear integrable equations,namely,universal character hierarchy,symplectic KP hierarchy and symplectic universal character hierarchy,respectively.In addition,the solutions of these integrable systems have been discussed. 展开更多
关键词 quantum fields generating functions integrable systems symmetric functions boson–fermion correspondence
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Improved Discrete Interval-Valued Stress-Strength Interference Model Based on Extended Universal Generating Function
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作者 高建雄 安宗文 白学宗 《Journal of Donghua University(English Edition)》 EI CAS 2016年第2期305-307,共3页
In practical engineering,sometimes the probability density functions( PDFs) of stress and strength can not be exactly determined,or only limited experiment data are available. In these cases,the traditional stress-str... In practical engineering,sometimes the probability density functions( PDFs) of stress and strength can not be exactly determined,or only limited experiment data are available. In these cases,the traditional stress-strength interference( SSI) model based on classical probabilistic approach can not be used to evaluate reliabilities of components. To solve this issue, the traditional universal generating function( UGF) is introduced and then it is extended to represent the discrete interval-valued random variable.Based on the extended UGF,an improved discrete interval-valued SSI model is proposed, which has higher calculation precision compared with the existing methods. Finally,an illustrative case is given to demonstrate the validity of the proposed model. 展开更多
关键词 RELIABILITY universal generating function(UGF) discrete interval-valued stress-strength interference(SSI) model
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On Moment Generating Function of Generalized Order Statistics from Erlang-Truncated Exponential Distribution
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作者 Anamika Kulshrestha R. U. Khan Devendra Kumar 《Open Journal of Statistics》 2012年第5期557-564,共8页
In this paper explicit expressions and some recurrence relations are derived for marginal and joint moment generating functions of generalized order statistics from Erlang-truncated exponential distribution. The resul... In this paper explicit expressions and some recurrence relations are derived for marginal and joint moment generating functions of generalized order statistics from Erlang-truncated exponential distribution. The results for k-th record values and order statistics are deduced from the relations derived. Further, a characterizing result of this distribution on using the conditional expectation of function of generalized order statistics is discussed. 展开更多
关键词 generalized Order STATISTICS Order STATISTICS Record Values Erlang-Truncated Exponential Distribution MARGINAL and Joint MOMENT generating function RECURRENCE Relations and Characterization
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Investigation of Probability Generating Function in an Interdependent <i>M/M/</i>1:(∞;GD) Queueing Model with Controllable Arrival Rates Using Rouche’s Theorem
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作者 Vishwa Nath Maurya 《Open Journal of Optimization》 2012年第2期34-38,共5页
Present paper deals a M/M/1:(∞;GD) queueing model with interdependent controllable arrival and service rates where- in customers arrive in the system according to poisson distribution with two different arrivals rate... Present paper deals a M/M/1:(∞;GD) queueing model with interdependent controllable arrival and service rates where- in customers arrive in the system according to poisson distribution with two different arrivals rates-slower and faster as per controllable arrival policy. Keeping in view the general trend of interdependent arrival and service processes, it is presumed that random variables of arrival and service processes follow a bivariate poisson distribution and the server provides his services under general discipline of service rule in an infinitely large waiting space. In this paper, our central attention is to explore the probability generating functions using Rouche’s theorem in both cases of slower and faster arrival rates of the queueing model taken into consideration;which may be helpful for mathematicians and researchers for establishing significant performance measures of the model. Moreover, for the purpose of high-lighting the application aspect of our investigated result, very recently Maurya [1] has derived successfully the expected busy periods of the server in both cases of slower and faster arrival rates, which have also been presented by the end of this paper. 展开更多
关键词 Interdependent QUEUEING Model BIVARIATE Poisson Process Controllable Arrival Rates Probability generating function Laplace Transform Rouche’s THEOREM Performance Measures
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Reliability Bounds based on Universal Generating Function and Discrete Stress-strength Interference Model
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作者 GUO Hui-xin SUO Bin ZHANG Gan-qing 《International Journal of Plant Engineering and Management》 2017年第3期175-187,共13页
A method for estimating the component reliability is proposed when the probability density functions of stress and strength can not be exactly determined. For two groups of finite experimental data about the stress an... A method for estimating the component reliability is proposed when the probability density functions of stress and strength can not be exactly determined. For two groups of finite experimental data about the stress and strength, an interval statistics method is introduced. The processed results are formulated as two interval-valued random variables and are graphically represented component reliability are proposed based on the by using two histograms. The lower and upper bounds of universal generating function method and are calculated by solving two discrete stress-strength interference models. The graphical calculations of the proposed reliability bounds are presented through a numerical example and the confidence of the proposed reliability bounds is discussed to demonstrate the validity of the proposed method. It is showed that the proposed reliability bounds can undoubtedly bracket the real reliability value. The proposed method extends the exciting universal generating function method and can give an interval estimation of component reliability in the case of lake of sufficient experimental data. An application example is given to illustrate the proposed method 展开更多
关键词 universal generating function discrete stress-strength interference model reliability bounds reliability estimation
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Lucas Symbolic Formulae and Generating Functions for Chebyshev Polynomials
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作者 Do Tan Si 《Journal of High Energy Physics, Gravitation and Cosmology》 2021年第3期914-924,共11页
This work shows that each kind of Chebyshev polynomials may be calculated from a symbolic formula similar to the Lucas formula for Bernoulli polynomials. It exposes also a new approach for obtaining generating functio... This work shows that each kind of Chebyshev polynomials may be calculated from a symbolic formula similar to the Lucas formula for Bernoulli polynomials. It exposes also a new approach for obtaining generating functions of them by operator calculus built from the derivative and the positional operators. 展开更多
关键词 Chebyshev Polynomials Lucas Symbolic Formula generating functions by Operator Calculus
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Some new exact solutions of Jacobian elliptic function about the generalized Boussinesq equation and Boussinesq-Burgers equation 被引量:8
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作者 张亮 张立凤 李崇银 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第2期403-410,共8页
By using the modified mapping method, we find some new exact solutions of the generalized Boussinesq equation and the Boussinesq-Burgers equation. The solutions obtained in this paper include Jacobian elliptic functio... By using the modified mapping method, we find some new exact solutions of the generalized Boussinesq equation and the Boussinesq-Burgers equation. The solutions obtained in this paper include Jacobian elliptic function solutions, combined Jacobian elliptic function solutions, soliton solutions, triangular function solutions. 展开更多
关键词 generalized Boussinesq equation Boussinesq-Burgers equation Jacobian elliptic function modified mapping method
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MONOTONICITY AND INEQUALITIES FOR THE GENERALIZED DISTORTION FUNCTION 被引量:2
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作者 马晓艳 褚玉明 王飞 《Acta Mathematica Scientia》 SCIE CSCD 2013年第6期1759-1766,共8页
The authors prove some monotonicity properties of functions involving the generalized Agard distortion function ηg(a,t), and obtain some inequalities for ηk(a, t) and relative distortion functions.
关键词 generalized modular equation generalized η-distortion function monotonic-ity inequality
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THE HILBERT BOUNDARY VALUE PROBLEM FOR GENERALIZED ANALYTIC FUNCTIONS IN CLIFFORD ANALYSIS 被引量:2
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作者 司中伟 杜金元 《Acta Mathematica Scientia》 SCIE CSCD 2013年第2期393-403,共11页
Let R0,n be the real Clifford algebra generated by e1, e2,... , en satisfying eiej+ejei=-2δij,i,j=1,2…,ne0 is the unit element.Let Ω be an open set. A function f is called left generalized analytic in ft if f sati... Let R0,n be the real Clifford algebra generated by e1, e2,... , en satisfying eiej+ejei=-2δij,i,j=1,2…,ne0 is the unit element.Let Ω be an open set. A function f is called left generalized analytic in ft if f satisfies the equation Lf=0,where ……qi 〉0, i =-, 1, - ……, n. In this article, we first give the kernel function for the generalized analytic function. Further, the Hilbert boundary value problem for generalized analytic functions in Rn+1 will be investigated. 展开更多
关键词 generalized analytic function Hilbert boundary value problem H^u function
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Improved theory of generalized meteo-ballistic weighting factor functions and their use 被引量:1
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作者 Vladimir CECH Jiri JEVICKY 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2016年第3期242-254,共13页
It follows from the analysis of artillery fire errors that approximately two-thirds of the inaccuracy of indirect artillery fire is caused by inaccuracies in the determination of the meteo parameters included in fire ... It follows from the analysis of artillery fire errors that approximately two-thirds of the inaccuracy of indirect artillery fire is caused by inaccuracies in the determination of the meteo parameters included in fire error budget model.Trajectories calculated under non-standard conditions are considered to be perturbed.The tools utilized for the analysis of perturbed trajectories are weighting factor functions(WFFs)which are a special kind of sensitivity functions.WFFs are used for calculation of meteo ballistic elements B(ballistic wind w B,densityρB,virtual temperatureτB,pressure p B)as well.We have found that the existing theory of WFF calculation has several significant shortcomings.The aim of the article is to present a new,improved theory of generalized WFFs that eliminates the deficiencies found.Using this theory will improve methods for designing firing tables,fire control systems algorithms,and meteo message generation algorithms. 展开更多
关键词 EXTERIOR BALLISTIC Non-standard projectile trajectory Perturbation Meteoconditions Sensitivity function (generalized) weighting (factor) function(curve) (generalized) EFFECT function Norm EFFECT
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Optimization of the Dressing Parameters in Cylindrical Grinding Based on a Generalized Utility Function 被引量:2
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作者 ALEKSANDROVA Irina 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2016年第1期63-73,共11页
The existing studies, concerning the dressing process, focus on the major influence of the dressing conditions on the grinding response variables. However, the choice of the dressing conditions is often made, based on... The existing studies, concerning the dressing process, focus on the major influence of the dressing conditions on the grinding response variables. However, the choice of the dressing conditions is often made, based on the experience of the qualified staff or using data from reference books. The optimal dressing parameters, which are only valid for the particular methods and dressing and grinding conditions, are also used. The paper presents a methodology for optimization of the dressing parameters in cylindrical grinding. The generalized utility function has been chosen as an optimization parameter. It is a complex indicator determining the economic, dynamic and manufacturing characteristics of the grinding process. The developed methodology is implemented for the dressing of aluminium oxide grinding wheels by using experimental diamond roller dressers with different grit sizes made of medium- and high-strength synthetic diamonds type AC32 and AC80. To solve the optimization problem, a model of the generalized utility function is created which reflects the complex impact of dressing parameters. The model is built based on the results from the conducted complex study and modeling of the grinding wheel lifetime, cutting ability, production rate and cutting forces during grinding. They are closely related to the dressing conditions (dressing speed ratio, radial in-feed of the diamond roller dresser and dress-out time), the diamond roller dresser grit size/grinding wheel grit size ratio, the type of synthetic diamonds and the direction of dressing. Some dressing parameters are determined for which the generalized utility fimction has a maximum and which guarantee an optimum combination of the following: the lifetime and cutting ability of the abrasive wheels, the tangential cutting force magnitude and the production rate of the grinding process. The results obtained prove the possibility of control and optimization of grinding by selecting particular dressing parameters. 展开更多
关键词 dressing conditions cylindrical grinding diamond roller dresser generalized utility function based optimization
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