Ferdowsi University of MashhadIranian Journal of Numerical Analysis and Optimization2423-69777220171001Image magniﬁcation by least squares surfacesبزرگنمایی تصویر توسط رویههای کمترین مربعات1142454110.22067/ijnao.v7i2.52815ENA.M.Esmaili ZainiDepartment of Applied Mathematics, Faculty of Mathematical Sciences, Yazd University,
Yazd , Iran.G.B.LoghmaniDepartment of Applied Mathematics, Faculty of Mathematical Sciences, Yazd University, Yazd , Iran.A.M.LatifDepartment of Computer Engineering, Faculty of Engineering, Yazd University, Yazd, Iran.Journal Article19700101Image magniﬁcation is one of the current issues of image processing in which keeping the quality and structure of images is the main concern. In im- age magniﬁcation, it is necessary to insert information in extra pixels. Adding information to an image should be compatible with the image structure with- out making artiﬁcial blocks. In this research, extra pixels are estimated using the surface of least squares, and all the pixels are reviewed according to the suggested edge-improving algorithm. The suggested ethod keeps the edges and minimizes the magniﬁed image opacity and the artiﬁcial blocks. Numer- ical results are presented by using PSNR and SSIM ﬁdelity measures and compared to some other methods. The average PSNR of the original image and image zooming is 32.79 which it shows that image zooming is very similar to the original image. Experimental results show that the proposed method has a better performance than others and provides good image quality.https://ijnao.um.ac.ir/article_24541_4c5f290d14203b23f1dd75a3012e940c.pdfFerdowsi University of MashhadIranian Journal of Numerical Analysis and Optimization2423-69777220171001Radial basis functions method for solving three-dimensional linear Fredholm integral equations on the cubic domainsروش ﺗﻮاﺑﻊ ﭘﺎﯾﻪ ﺷﻌﺎﻋﯽ ﺑﺮای ﺣﻞ ﻣﻌﺎدﻻت اﻧﺘﮕﺮال ﻓﺮدﻫﻠﻢ ﺧﻄﯽ ﺳﻪ ﺑﻌﺪی روی داﻣﻨﻪ ﻫﺎی ﻣﮑﻌﺒﯽ15382454910.22067/ijnao.v7i2.52085ENM.EsmaeilbeigiDepartment of Mathematics, Faculty of Mathematical Sciences and Statistics, Malayer University, Malayer, Iran.F.MirzaeeDepartment of Mathematics, Faculty of Mathematical Sciences and Statistics, Malayer University, Malayer, Iran.D.MoazamiDepartment of Mathematics, Faculty of Mathematical Sciences and Statistics, Malayer University, Malayer, Iran.Journal Article19700101The main purpose of this article is to describe a numerical scheme for solving three-dimensional linear Fredholm integral equations of the second kind on the cubic domains. The method is based on interpolation by radial basis functions (RBFs) based on Gauss-Legendre nodes and weights. Error analysis is presented for this method. Finally, several examples are given and numerical examples are presented to demonstrate the validity and applicability of the method.https://ijnao.um.ac.ir/article_24549_9bffd7ba440c0dd9c09c1905b05bf307.pdfFerdowsi University of MashhadIranian Journal of Numerical Analysis and Optimization2423-69777220171001Payment scheduling under project crashing based on project progressفشردهسازی پروژه در مسئله زمانبندی پرداخت براساس پیشرفت پروژه39562455710.22067/ijnao.v7i2.46395ENM.Mortazavi NejadDepartment of Applied Mathematics, Faculty of Mathematical Sciences, Ferdowsi University of Mashhad, Mashhad, Iran.H.R.TareghianDepartment of Applied Mathematics, Faculty of Mathematical Sciences, Ferdowsi University of Mashhad, Mashhad, Iran.Z.SariDepartment of Applied Mathematics, Faculty of Mathematical Sciences, Ferdowsi University of Mashhad, Mashhad, Iran.Journal Article19700101In this paper, we address a new problem in the context of project payment scheduling when project activities are allowed to be crashed with the purpose of maximizing the contractors net present value (NPV). We assume that the contractor is paid at some pre-specified points of time according to the volume of work performed. Upon completion of activities, the cost of their execution is paid. Two different approaches are used to determine the volume of work performed at so called review points. In the first approach, only completed activities are considered. In the second approach, any portions of the activities that are executed are considered. To increase the volume of work performed at the review points, the contractor may decide to crash some activities and as such possibly increases his NPV. As activity crashing costs the contractor money, a compromise needs to be made. Two mathematical models are developed to study each approach and hence help the contractor to make the best decision. These models offer a means of investigating whether it is advisable to crash some activities and are therefore of practical importance. It is shown that the contractor may increase his NPV, even when he pays for the activity crashing costs. The performance of the mathematical models is illustrated using a numerical example.https://ijnao.um.ac.ir/article_24557_9ad8b3c758bef4a639c8ee52e718adcb.pdfFerdowsi University of MashhadIranian Journal of Numerical Analysis and Optimization2423-69777220171001Augmented Lagrangian Method for Finding Minimum Norm Solution to the Absolute Value Equationروش ﻻﮔﺮاﻧﮋ ﺑﻬﺒﻮد ﯾﺎﻓﺘﻪ ﺑﺮای ﭘﯿﺪا ﮐﺮدن ﺟﻮاب ﺑﺎ ﮐﻤﺘﺮﯾﻦ ﻧﺮم- ١ دﺳﺘﮕﺎه ﻣﻌﺎدﻻت ﻗﺪر مطلق57642456710.22067/ijnao.v7i2.57912ENS.KetabchiDepartment of Applied Mathematics, Faculty of Mathematical Sciences, University of Guilan, P.O. Box 1914, Rasht, Iran.H.MoosaeiDepartment of Mathematics, Faculty of Science, University of Bojnord, Bojnord, Iran.Journal Article19700101In this paper, we give an algorithm to compute the minimum 1-norm solution to the absolute value equation (AVE). The augmented Lagrangian method is investigated for solving this problems . This approach leads to an unconstrained minimization problem with once differentiable convex objective function. We propose a quasi-Newton method for solving unconstrained optimization problem. Computational results show that convergence to high accuracy often occurs in just a few iterations.https://ijnao.um.ac.ir/article_24567_25c1b6aedf63ce96172f888d48396484.pdfFerdowsi University of MashhadIranian Journal of Numerical Analysis and Optimization2423-69777220171001The state of the art in Dynamic Relaxation methods for structural mechanics Part 1: Formulationsمروری ﺑﺮ روش ﻫﺎی رﻫﺎﯾﯽ ﭘﻮﯾﺎ در ﺳﺎزه ﻫﺎی ﻣﮑﺎﻧﯿﮑﯽ ﺑﺨﺶ اول : راﺑﻄﻪ ﺳﺎزی ها65862457510.22067/ijnao.v7i2.60552ENMohammadRezaiee-PajandDepartment of Civil Engineering, Factualy of Engineering, Ferdowsi Unversity of Mashhad, Mashhad, Iran.0000-0002-8808-0011J.AlamatianCivil Engineering Department, Mashhad Branch, Islamic Azad Unversity, Mashhad, Iran.HasineRezaeeDepartment of Civil Engineering, Factualy of Engineering, Ferdowsi Unversity of Mashhad, Mashhad, Iran.Journal Article19700101In the last sixty years, the Dynamic Relaxation methods have evolved significantly. These explicit and iterative procedures are frequently used to solve the linear or nonlinear response of governing equations resulted from structural analyses. In the first part of this study, the common DR formulations are reviewed. Mathematical bases and also physical concepts of these solvers are explained briefly. All the DR parameters, i.e. fictitious mass, fictitious damping, fictitious time step and initial guess are described, as well. Furthermore, solutions of structural problems along with kinetic and viscous damping formulations are discussed. Analyses of the existing studies and suggestions for future research trends are presented. In the second part, the applications of Dynamic Relaxation method in engineering practices are reviewed.https://ijnao.um.ac.ir/article_24575_c993a459a801bdd6171650a1130226da.pdfFerdowsi University of MashhadIranian Journal of Numerical Analysis and Optimization2423-69777220171001The state of the art in Dynamic Relaxation methods for structural mechanics Part 2: Applicationsمروری بر روش های رهایی پویا در سازه های مکانیکی بخش دوم : کاربردها871142458610.22067/ijnao.v7i2.67470ENM.Rezaiee-PajandDepartment of Civil Engineering, Factualy of Engineering, Ferdowsi Unversity of Mashhad, Mashhad, Iran.0000-0002-8808-0011J.AlamatianCivil Engineering Department, Mashhad Branch, Islamic Azad Unversity, Mashhad, Iran.H.RezaeeDepartment of Civil Engineering, Factualy of Engineering, Ferdowsi Unversity of Mashhad, Mashhad, Iran.Journal Article19700101The most significant advances over the sixty years relative to the Dynamic Relaxation applications in structural engineering are summarized. Emphasized are given towards plates, form finding, cable structures, dynamic analysis, and other applications. The role of DR solver in the linear and non-linear analyses is discussed. This investigation is undertaken to explain the application of the solution technique to the static, dynamic and stability problems. The influence of the methods on the use of isotropic and composite materials, such as orthotropic and laminated ones, is briefly covered. Critical analyses and suggestions regarding future research and applications will be presented.https://ijnao.um.ac.ir/article_24586_0c73509c02360988751d269ab28e51fa.pdfFerdowsi University of MashhadIranian Journal of Numerical Analysis and Optimization2423-69777220171001Using a LDG method for solving an inverse source problem of the time-fractional diffusion equationاستفاده از یک روش LDGبرای حل مساله منبع وارون از نوع معادله انتشار کسری-زمانی1151352459110.22067/ijnao.v7i2.62042ENS.YeganehDepartment of Mathematical Sciences, Isfahan University of Technology, Isfahan 84156-
83111, Iran.R.MokhtariDepartment of Mathematical Sciences, Isfahan University of Technology, Isfahan 84156-
83111, Iran.0000-0002-1420-0949S.FouladiDepartment of Mathematical Sciences, Isfahan University of Technology, Isfahan 84156-
83111, Iran.Journal Article19700101In this paper, we apply a local discontinuous Galerkin (LDG) method to solve some fractional inverse problems. In fact, we determine a timedependent source term in an inverse problem of the time-fractional diffusion equation. The method is based on a finite difference scheme in time and a LDG method in space. A numerical stability theorem as well as an error estimate is provided. Finally, some numerical examples are tested to confirm theoretical results and to illustrate effectiveness of the method. It must be pointed out that proposed method generates stable and accurate numerical approximations without using any regularization methods which are necessary for other numerical methods for solving such ill-posed inverse problems.https://ijnao.um.ac.ir/article_24591_7602ffbeb5b87ec2fc9fdb723942918a.pdf