فیلترها/جستجو در نتایج    

فیلترها

سال

بانک‌ها




گروه تخصصی











متن کامل


نویسندگان: 

Rafiee A. | Moradi P. | Ghaderzadeh A.

اطلاعات دوره: 
  • سال: 

    1400
  • دوره: 

    51
  • شماره: 

    4
  • صفحات: 

    443-454
تعامل: 
  • استنادات: 

    0
  • بازدید: 

    187
  • دانلود: 

    37
چکیده: 

Multi-label classification aims at assigning more than one label to each instance. Many real-world multi-label classification tasks are high dimensional, leading to reduced performance of traditional classifiers. Feature selection is a common approach to tackle this issue by choosing prominent features. Multi-label feature selection is an NP-hard approach, and so far, some swarm intelligence-based strategies and have been proposed to find a near optimal solution within a reasonable time. In this paper, a hybrid intelligence algorithm based on the binary algorithm of particle swarm optimization and a novel LOCAL search strategy has been proposed to select a set of prominent features. To this aim, features are divided into two categories based on the extension rate and the relationship between the output and the LOCAL search strategy to increase the convergence speed. The first group features have more similarity to class and less similarity to other features, and the second is redundant and less relevant features. Accordingly, a LOCAL operator is added to the particle swarm optimization algorithm to reduce redundant features and keep relevant ones among each solution. The aim of this operator leads to enhance the convergence speed of the proposed algorithm compared to other algorithms presented in this field. Evaluation of the proposed solution and the proposed statistical test shows that the proposed approach improves different classification criteria of multi-label classification and outperforms other METHODs in most cases. Also in cases where achieving higher accuracy is more important than time, it is more appropriate to use this METHOD.

شاخص‌های تعامل:   مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

بازدید 187

مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesدانلود 37 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesاستناد 0 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesمرجع 0
اطلاعات دوره: 
  • سال: 

    2013
  • دوره: 

    44
تعامل: 
  • بازدید: 

    137
  • دانلود: 

    0
چکیده: 

THIS PAPER PRESENTS THE LOCAL RADIAL BASIS FUNCTION BASED ON FINITE DIFFERENCE (LRBF-FD) FOR THE SINE-GORDON EQUATION. SOME ADVANTAGES OF THE PROPOSED METHOD ARE THAT THIS METHOD IS MESH FREE UNLIKE FINITE DIFFERENCE (FD) AND FINITE ELEMENT (FE) METHODS, AND ITS COEFFICIENT MATRIX IS SPARSE AND WELL-CONDITIONED AS COMPARED WITH THE GLOBAL RBF COLLOCATION METHOD (GRBF).NUMERICAL RESULTS SHOW THAT THE LRBF-FD METHOD HAS GOOD AC-CURACY AS COMPARED WITH GRBF.

شاخص‌های تعامل:   مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

بازدید 137

مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesدانلود 0
نویسنده: 

YAZDANI A. | Hadizadeh Yazdi M.

اطلاعات دوره: 
  • سال: 

    2016
  • دوره: 

    47
تعامل: 
  • بازدید: 

    212
  • دانلود: 

    0
چکیده: 

IN THIS PAPER, A HYBRID NUMERICAL METHOD BASED ON LOCAL POLYNOMIAL SPLINES IS GENERALIZED FOR APPROXIMATE SOLUTION OF TWO DIMENSIONAL VOLTERRA INTEGRAL EQUATIONS. THE PROPOSED SCHEME IS A UNIVARIATE B-SPLINE COLLOCATION METHOD WITH A CUBATURE FORMULA FOR NUMERICAL EVALUATION OF INTEGRAL CONTAINING THE KERNEL BASED ON BIVARIATE SPLINE FUNCTIONS. COMPUTATIONAL FEATURES AND SOME NUMERICAL EXPERIMENTS ARE ALSO REPORTED.

شاخص‌های تعامل:   مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

بازدید 212

مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesدانلود 0
مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources
نویسندگان: 

ESLAHCHI M.R. | PARVIZI M.

اطلاعات دوره: 
  • سال: 

    2013
  • دوره: 

    8
  • شماره: 

    1
  • صفحات: 

    91-104
تعامل: 
  • استنادات: 

    0
  • بازدید: 

    426
  • دانلود: 

    0
چکیده: 

In this paper we present a new METHOD to find simple or multiple roots of functions in a finite interval. In this METHOD using bisection METHOD we can find an interval such that this function is one to one on it, thus we can transform problem of finding roots in this interval into an ordinary differential equation with boundary conditions.By solving this equation using COLLOCATION METHOD we can find a root for given function in the special interval. We also present convergence analysis of the new METHOD. Finally some examples are given to show efficiency of the presented METHOD.

شاخص‌های تعامل:   مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

بازدید 426

مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesدانلود 0 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesاستناد 0 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesمرجع 2
نویسنده: 

BASERI A. | GHOREISHI F. | PISHBIN S.

اطلاعات دوره: 
  • سال: 

    2013
  • دوره: 

    5
تعامل: 
  • بازدید: 

    153
  • دانلود: 

    0
چکیده: 

IN THIS PAPER, WE WILL PRESENT A NEW ALGORITHM FOR SOLVING ITO STOCHASTIC DIFFERENTIAL EQUATIONS (SDES) IN CONTINUOUS PIECEWISE POLYNOMIAL SPACE. IN THIS APPROACH, WE WILL EMPLOY PIECEWISE COLLOCATION METHOD FOR DRIFT AND DIFFUSION TERMS OF THE GIVEN EQUATION. CONVERGENCE ORDER OF THE METHOD IS INVESTIGATED AND SOME NUMERICAL EXAMPLES ARE CONSIDERED TO DEMONSTRATE THE EFFICIENCY AND ROBUSTNESS OF THE METHOD.

شاخص‌های تعامل:   مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

بازدید 153

مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesدانلود 0
نویسندگان: 

LAMNII A. | MRAOUI H.

اطلاعات دوره: 
  • سال: 

    2013
  • دوره: 

    3
  • شماره: 

    1
  • صفحات: 

    11-23
تعامل: 
  • استنادات: 

    4
  • بازدید: 

    385
  • دانلود: 

    0
چکیده: 

The spline COLLOCATION METHOD is used to approximate solutions of boundary value problems. The convergence analysis is given and the METHOD is shown to have second-order convergence. A numerical illustration is given to show the pertinent features of the technique.

شاخص‌های تعامل:   مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

بازدید 385

مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesدانلود 0 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesاستناد 4 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesمرجع 1
مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources
اطلاعات دوره: 
  • سال: 

    1402
  • دوره: 

    49
  • شماره: 

    2
  • صفحات: 

    371-388
تعامل: 
  • استنادات: 

    0
  • بازدید: 

    63
  • دانلود: 

    18
چکیده: 

به دلیل عدم وجود اطلاعات کافی در مورد چگالی اجرام زیرسطحی، در مدل سازی میدان گرانی زمین، معمولاً از میانگین جهانی چگالی به صورت عددی ثابت در کل منطقه موردمطالعه استفاده می شود. در حالی که، افزایش دقت تقریب چگالی در مدل سازی اثر گرانش ناشی از جرم توپوگرافی، دقت مدل سازی میدان گرانی را بالاتر خواهد برد. برای امکان سنجی این موضوع، از یک مدل چگالی توپوگرافی با قدرت تفکیک "30×"30 که از پردازش نقشه های لرزه نگاری و اطلاعات ماهواره ای لایه های لیتوسفر تهیه شده، برای افزایش دقت تقریب چگالی ثابت در چهار منطقه مطالعاتی درون ایران با وضعیت توپوگرافی و پراکندگی داده متفاوت استفاده شده است. به این ترتیب که، علاوه بر مقدار میانگین جهانی، مقدار میانگین چگالی در ایران و منطقه نیز در مدل سازی اثر گرانش ناشی از جرم توپوگرافی لحاظ شد. در مدل سازی میدان گرانی، روش کالوکیشن کمترین مربعات و به تبع، تکنیک RTM در مدل سازی اثر گرانش ناشی از جرم توپوگرافی به کار گرفته شد. همچنین، افزون بر اصلاح چگالی، استفاده از رویکرد کوواریانس بهبودیافته در مدل سازی میدان گرانی نیز مورد ارزیابی واقع شد. نتایج مقایسه با نقاط کنترلی این پژوهش نشان می دهد، به کارگیری اصلاح چگالی و رویکرد کوواریانس بهبودیافته در مناطق با توپوگرافی خشن و فاقد داده گرانی سنجی کافی و پراکندگی مناسب، به شکل قابل اعتنایی (88/1 میلی­گال معادل %6/15 در منطقه مطالعاتی این پژوهش) باعث افزایش دقت مدل سازی میدان گرانی می شود.

شاخص‌های تعامل:   مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

بازدید 63

مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesدانلود 18 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesاستناد 0 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesمرجع 0
اطلاعات دوره: 
  • سال: 

    2018
  • دوره: 

    6
  • شماره: 

    3
  • صفحات: 

    326-338
تعامل: 
  • استنادات: 

    0
  • بازدید: 

    40
  • دانلود: 

    0
چکیده: 

The non-LOCAL hyperbolic partial differential equations have many applications in sciences and engineering. A COLLOCATION finite element approach based on exponential cubic B-spline and quintic B-spline are presented for the numerical solution of the wave equation subject to nonLOCAL boundary condition. Von Neumann stability analysis is used to analyze the proposed METHODs. The efficiency, accuracy and stability of the METHODs are assessed by applying it to the test problem. The results are found to be in good agreement with known solutions and with existing COLLOCATION schemes in literature.

شاخص‌های تعامل:   مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

بازدید 40

مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesدانلود 0 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesاستناد 0 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesمرجع 0
اطلاعات دوره: 
  • سال: 

    2021
  • دوره: 

    9
  • شماره: 

    4
  • صفحات: 

    1176-1197
تعامل: 
  • استنادات: 

    0
  • بازدید: 

    35
  • دانلود: 

    0
چکیده: 

In this paper, a Laguerre COLLOCATION METHOD is presented in order to obtain numer-ical solutions for linear and nonlinear Lane-Emden type equations and their initial conditions. The basis of the present METHOD is operational matrices with respect to modi , ed generalized Laguerre polynomials(MGLPs) that transforms the solu-tion of main equation and its initial conditions to the solution of a matrix equation corresponding to the system of algebraic equations with the unknown Laguerre co-e, cients. By solving this system, coe, cients of approximate solution of the main problem will be determined. Implementation of the METHOD is easy and has more accurate results in comparison with results of other METHODs.

شاخص‌های تعامل:   مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

بازدید 35

مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesدانلود 0 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesاستناد 0 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesمرجع 0
اطلاعات دوره: 
  • سال: 

    2009
  • دوره: 

    7
  • شماره: 

    1
  • صفحات: 

    9-18
تعامل: 
  • استنادات: 

    0
  • بازدید: 

    485
  • دانلود: 

    0
چکیده: 

A meshless approach, COLLOCATION discrete least square (CDLS) METHOD, is extended in this paper, for solving elasticity problems. In the present CDLS METHOD, the problem domain is discretized by distributed field nodes. The field nodes are used to construct the trial functions. The moving least-squares interpolant is employed to construct the trial functions. Some COLLOCATION points that are independent of the field nodes are used to form the total residuals of the problem. The least-squares technique is used to obtain the solution of the problem by minimizing the summation of the residuals for the COLLOCATION points. The final stiffness matrix is symmetric and therefore can be solved via efficient solvers. The boundary conditions are easily enforced by the penalty METHOD. The present METHOD does not require any mesh so it is a truly meshless METHOD. Numerical examples are studied in detail, which show that the present METHOD is stable and possesses good accuracy, high convergence rate and high efficiency.

شاخص‌های تعامل:   مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

بازدید 485

مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesدانلود 0 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesاستناد 0 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesمرجع 0
litScript
telegram sharing button
whatsapp sharing button
linkedin sharing button
twitter sharing button
email sharing button
email sharing button
email sharing button
sharethis sharing button