Moh. Ivan Azis - Academia.edu (original) (raw)

Papers by Moh. Ivan Azis

Research paper thumbnail of Reduced order model for simulation of air pollution model and application in 2D urban street canyons via the meshfree gradient smoothing method

Computers & Mathematics with Applications

Research paper thumbnail of A boundary-only element method for 2D unsteady diffusion convection reaction problems of trigonometrically graded anisotropic materials

International Journal for Computational Methods in Engineering Science and Mechanics

Research paper thumbnail of Numerical Solutions for 2D Unsteady Laplace-Type Problems of Anisotropic Functionally Graded Materials

Mathematical Modelling and Analysis

The time-dependent Laplace-type equation of variable coefficients for anisotropic inhomogeneous m... more The time-dependent Laplace-type equation of variable coefficients for anisotropic inhomogeneous media is discussed in this paper. Numerical solutions to problems which are governed by the equation are sought by using a combined Laplace transform and boundary element method. The variable coefficients equation is transformed to a constant coefficients equation. The constant coefficients equation after being Laplace transformed is then written in a boundary-only integral equation involving a time-free fundamental solution. The boundary integral equation is therefore employed to find the numerical solutions using a standard boundary element method. Finally the numerical results are inversely transformed numerically using the Stehfest formula to obtain solutions in the time variable. Some problems of anisotropic functionally graded media are considered. The results show that the combined Laplace transform and boundary element method is accurate and easy to implement.

Research paper thumbnail of Lembar Peer Review HKI Abang

Repository Nusamandiri, 2019

Research paper thumbnail of Lembar Peer Review HKI Akeu

Repository Nusamandiri, 2020

Research paper thumbnail of Angka-Angka Ramsey Bahkan Untuk Bintang Berhadapan Roda - Roda Datar

Research paper thumbnail of Penambahan Spirulina Pada Poto Poto Untuk Meningkatkan Kualitas Produk Pangan di Kab. Sinjai

Spirulina is a marine phytoplankton that is a microalgae that has great potential in life, one of... more Spirulina is a marine phytoplankton that is a microalgae that has great potential in life, one of which is food, because the nutritional coverage contained in this marine phytoplankton includes proteins, carbohydrates, vitamins, minerals, essential fatty acids DHA and EPA so that it can be used as an alternative nutritious food. . The purpose of this activity is to training on inovative snack “Poto Poto Sinjai”, how to make Spirulina in Bongki Village, Sinjai Regency. The method used in this activity consisted of a location survey and the production of snack from Spirulina . The implementation phase of the activity using counseling methods and training on the benefits of Spirulina as nutritious food and making snack Spirulina. The results of the implementation of this activity were the increase in participants' knowledge about snack Spirulina, as a highly nutritious snack. The results of the knowledge improvement test show that there is a fairly good increase in knowledge of the...

Research paper thumbnail of On some problems concerning deformations of functionally graded anisotropic elastic materials

The 2nd International Conference on Engineering and Natural Sciences (ICENS) di Waseda University... more The 2nd International Conference on Engineering and Natural Sciences (ICENS) di Waseda University Japan pada tanggal 22 s/d 24 Juli 2015.

Research paper thumbnail of A boundary integral investigation for unsteady modified Helmholtz problems of some other classes of anisotropic functionally graded materials

International Journal of Computational Materials Science and Engineering, 2021

Numerical solutions for a class of unsteady modified Helmholtz problems of anisotropic functional... more Numerical solutions for a class of unsteady modified Helmholtz problems of anisotropic functionally graded materials are sought. The governing equation which is a variable coefficients equation is ...

Research paper thumbnail of A boundary element method for transient heat conduction problem of nonhomogeneous anisotropic materials

A boundary element method (BEM) is obtained for the nonlinear transient heat conduction problem o... more A boundary element method (BEM) is obtained for the nonlinear transient heat conduction problem of inhomogeneous anisotropic media.

Research paper thumbnail of Aplikasi Abang (Absensi Anak Magang)

Research paper thumbnail of Duality Property for Linear Canonical Transform

Journal of Physics: Conference Series, 2019

In the present we first introduce adjoint operators of the linear canonical transform. It is show... more In the present we first introduce adjoint operators of the linear canonical transform. It is shown the adjoint of the the linear canonical transform is its inverse. We finally derive duality property of the linear canonical transform.

Research paper thumbnail of Stability and Optimal Harvesting of Modified Leslie-Gower Predator-Prey Model

Journal of Physics: Conference Series, 2018

This paper studies a modified of dynamics of Leslie-Gower predator-prey population model. The mod... more This paper studies a modified of dynamics of Leslie-Gower predator-prey population model. The model is stated as a system of first order differential equations. The model consists of one predator and one prey. The Holling typ e II as a predation function is considered in this model. The predator and prey populations are assumed to be beneficial and then the two populations are harvested with constant efforts. Existence and stability of the interior equilibrium point are analysed. Linearization method is used to get the linearized model and the eigenvalue is used to justify the stability of the interior equilibrium point. From the analyses, we show that under a certain condition the interior equilibrium point exists and is locally asymptotically stable. For the model with constant efforts of harvesting, cost function, revenue function, and profit function are considered. The stable interior equilibrium point is then related to the maximum profit problem as well as net present valu e of revenues problem. We show that there exists a certain value of the efforts that maximizes the profit function and net present value of revenues while the interior equilibrium point remains stable. This means that the populations can live in coexistence for a long time and also maximize the benefit even though the populations are harvested with constant efforts.

Research paper thumbnail of Standard-BEM solutions to two types of anisotropic-diffusion convection reaction equations with variable coefficients

Engineering Analysis with Boundary Elements, 2019

Two versions of diffusion-convection-reaction equations for anisotropic functionally graded mater... more Two versions of diffusion-convection-reaction equations for anisotropic functionally graded materials (FGMs) are discussed again in this paper to find their numerical solutions by using the boundary element method (BEM). The numerical results obtained show the consistency and accuracy of the BEM solutions. Also, the solutions exhibit the impact of the anisotropy and inhomogeneity (spatial variability) of the media.

Research paper thumbnail of Numerical solutions for the Helmholtz boundary value problems of anisotropic homogeneous media

Journal of Computational Physics, 2019

Numerical solutions to boundary value problems governed by twodimensional Helmholtz equation for ... more Numerical solutions to boundary value problems governed by twodimensional Helmholtz equation for anisotropic media is obtained. The standard BEM has been employed to obtain the solutions. The results show that the anisotropy of the medium under consideration causes effects on the solution. The anisotropy of the medium should be taken into account for the implementation of the modeling and computation.

Research paper thumbnail of A boundary element method with analytical integration for deformation of inhomogeneous elastic materials

Journal of Physics: Conference Series, 2018

This paper is concerned with obtaining solutions to the equation governing static deformations of... more This paper is concerned with obtaining solutions to the equation governing static deformations of inhomogeneous elastic materials. The material parameters are assumed to vary continuously with the spatial variables. A boundary element method (BEM) with analytical integration is used to find the solutions. The results show that the BEM is feasible to be used to find the solutions of the problems and with analytical integration the BEM gives very accurate solutions in a shorter computation time.

Research paper thumbnail of A Boundary Element Method for 2D Diffusion-Convection Problems in Anisotropic Media

Far East Journal of Mathematical Sciences (FJMS), 2017

A boundary element method (BEM) is obtained for a boundary value problem of homogeneous anisotrop... more A boundary element method (BEM) is obtained for a boundary value problem of homogeneous anisotropic media governed by diffusion-convection equation.

Research paper thumbnail of Bem Solutions for Unsteady Transport Problems in Anisotropic Media

JP Journal of Heat and Mass Transfer, 2018

Research paper thumbnail of Fundamental Solutions to Two Types of 2D Boundary Value Problems of Anisotropic Materials

Far East Journal of Mathematical Sciences (FJMS), 2017

Research paper thumbnail of A boundary element method for a class of elliptic boundary value problems of functionally graded media

Engineering Analysis with Boundary Elements, 2017

A Boundary Element Method (BEM) is derived for obtaining solutions to a class of elliptic boundar... more A Boundary Element Method (BEM) is derived for obtaining solutions to a class of elliptic boundary value problems (BVPs) of functionally graded media (FGM). Some particular examples are considered to illustrate the application of the BEM.

Research paper thumbnail of Reduced order model for simulation of air pollution model and application in 2D urban street canyons via the meshfree gradient smoothing method

Computers & Mathematics with Applications

Research paper thumbnail of A boundary-only element method for 2D unsteady diffusion convection reaction problems of trigonometrically graded anisotropic materials

International Journal for Computational Methods in Engineering Science and Mechanics

Research paper thumbnail of Numerical Solutions for 2D Unsteady Laplace-Type Problems of Anisotropic Functionally Graded Materials

Mathematical Modelling and Analysis

The time-dependent Laplace-type equation of variable coefficients for anisotropic inhomogeneous m... more The time-dependent Laplace-type equation of variable coefficients for anisotropic inhomogeneous media is discussed in this paper. Numerical solutions to problems which are governed by the equation are sought by using a combined Laplace transform and boundary element method. The variable coefficients equation is transformed to a constant coefficients equation. The constant coefficients equation after being Laplace transformed is then written in a boundary-only integral equation involving a time-free fundamental solution. The boundary integral equation is therefore employed to find the numerical solutions using a standard boundary element method. Finally the numerical results are inversely transformed numerically using the Stehfest formula to obtain solutions in the time variable. Some problems of anisotropic functionally graded media are considered. The results show that the combined Laplace transform and boundary element method is accurate and easy to implement.

Research paper thumbnail of Lembar Peer Review HKI Abang

Repository Nusamandiri, 2019

Research paper thumbnail of Lembar Peer Review HKI Akeu

Repository Nusamandiri, 2020

Research paper thumbnail of Angka-Angka Ramsey Bahkan Untuk Bintang Berhadapan Roda - Roda Datar

Research paper thumbnail of Penambahan Spirulina Pada Poto Poto Untuk Meningkatkan Kualitas Produk Pangan di Kab. Sinjai

Spirulina is a marine phytoplankton that is a microalgae that has great potential in life, one of... more Spirulina is a marine phytoplankton that is a microalgae that has great potential in life, one of which is food, because the nutritional coverage contained in this marine phytoplankton includes proteins, carbohydrates, vitamins, minerals, essential fatty acids DHA and EPA so that it can be used as an alternative nutritious food. . The purpose of this activity is to training on inovative snack “Poto Poto Sinjai”, how to make Spirulina in Bongki Village, Sinjai Regency. The method used in this activity consisted of a location survey and the production of snack from Spirulina . The implementation phase of the activity using counseling methods and training on the benefits of Spirulina as nutritious food and making snack Spirulina. The results of the implementation of this activity were the increase in participants' knowledge about snack Spirulina, as a highly nutritious snack. The results of the knowledge improvement test show that there is a fairly good increase in knowledge of the...

Research paper thumbnail of On some problems concerning deformations of functionally graded anisotropic elastic materials

The 2nd International Conference on Engineering and Natural Sciences (ICENS) di Waseda University... more The 2nd International Conference on Engineering and Natural Sciences (ICENS) di Waseda University Japan pada tanggal 22 s/d 24 Juli 2015.

Research paper thumbnail of A boundary integral investigation for unsteady modified Helmholtz problems of some other classes of anisotropic functionally graded materials

International Journal of Computational Materials Science and Engineering, 2021

Numerical solutions for a class of unsteady modified Helmholtz problems of anisotropic functional... more Numerical solutions for a class of unsteady modified Helmholtz problems of anisotropic functionally graded materials are sought. The governing equation which is a variable coefficients equation is ...

Research paper thumbnail of A boundary element method for transient heat conduction problem of nonhomogeneous anisotropic materials

A boundary element method (BEM) is obtained for the nonlinear transient heat conduction problem o... more A boundary element method (BEM) is obtained for the nonlinear transient heat conduction problem of inhomogeneous anisotropic media.

Research paper thumbnail of Aplikasi Abang (Absensi Anak Magang)

Research paper thumbnail of Duality Property for Linear Canonical Transform

Journal of Physics: Conference Series, 2019

In the present we first introduce adjoint operators of the linear canonical transform. It is show... more In the present we first introduce adjoint operators of the linear canonical transform. It is shown the adjoint of the the linear canonical transform is its inverse. We finally derive duality property of the linear canonical transform.

Research paper thumbnail of Stability and Optimal Harvesting of Modified Leslie-Gower Predator-Prey Model

Journal of Physics: Conference Series, 2018

This paper studies a modified of dynamics of Leslie-Gower predator-prey population model. The mod... more This paper studies a modified of dynamics of Leslie-Gower predator-prey population model. The model is stated as a system of first order differential equations. The model consists of one predator and one prey. The Holling typ e II as a predation function is considered in this model. The predator and prey populations are assumed to be beneficial and then the two populations are harvested with constant efforts. Existence and stability of the interior equilibrium point are analysed. Linearization method is used to get the linearized model and the eigenvalue is used to justify the stability of the interior equilibrium point. From the analyses, we show that under a certain condition the interior equilibrium point exists and is locally asymptotically stable. For the model with constant efforts of harvesting, cost function, revenue function, and profit function are considered. The stable interior equilibrium point is then related to the maximum profit problem as well as net present valu e of revenues problem. We show that there exists a certain value of the efforts that maximizes the profit function and net present value of revenues while the interior equilibrium point remains stable. This means that the populations can live in coexistence for a long time and also maximize the benefit even though the populations are harvested with constant efforts.

Research paper thumbnail of Standard-BEM solutions to two types of anisotropic-diffusion convection reaction equations with variable coefficients

Engineering Analysis with Boundary Elements, 2019

Two versions of diffusion-convection-reaction equations for anisotropic functionally graded mater... more Two versions of diffusion-convection-reaction equations for anisotropic functionally graded materials (FGMs) are discussed again in this paper to find their numerical solutions by using the boundary element method (BEM). The numerical results obtained show the consistency and accuracy of the BEM solutions. Also, the solutions exhibit the impact of the anisotropy and inhomogeneity (spatial variability) of the media.

Research paper thumbnail of Numerical solutions for the Helmholtz boundary value problems of anisotropic homogeneous media

Journal of Computational Physics, 2019

Numerical solutions to boundary value problems governed by twodimensional Helmholtz equation for ... more Numerical solutions to boundary value problems governed by twodimensional Helmholtz equation for anisotropic media is obtained. The standard BEM has been employed to obtain the solutions. The results show that the anisotropy of the medium under consideration causes effects on the solution. The anisotropy of the medium should be taken into account for the implementation of the modeling and computation.

Research paper thumbnail of A boundary element method with analytical integration for deformation of inhomogeneous elastic materials

Journal of Physics: Conference Series, 2018

This paper is concerned with obtaining solutions to the equation governing static deformations of... more This paper is concerned with obtaining solutions to the equation governing static deformations of inhomogeneous elastic materials. The material parameters are assumed to vary continuously with the spatial variables. A boundary element method (BEM) with analytical integration is used to find the solutions. The results show that the BEM is feasible to be used to find the solutions of the problems and with analytical integration the BEM gives very accurate solutions in a shorter computation time.

Research paper thumbnail of A Boundary Element Method for 2D Diffusion-Convection Problems in Anisotropic Media

Far East Journal of Mathematical Sciences (FJMS), 2017

A boundary element method (BEM) is obtained for a boundary value problem of homogeneous anisotrop... more A boundary element method (BEM) is obtained for a boundary value problem of homogeneous anisotropic media governed by diffusion-convection equation.

Research paper thumbnail of Bem Solutions for Unsteady Transport Problems in Anisotropic Media

JP Journal of Heat and Mass Transfer, 2018

Research paper thumbnail of Fundamental Solutions to Two Types of 2D Boundary Value Problems of Anisotropic Materials

Far East Journal of Mathematical Sciences (FJMS), 2017

Research paper thumbnail of A boundary element method for a class of elliptic boundary value problems of functionally graded media

Engineering Analysis with Boundary Elements, 2017

A Boundary Element Method (BEM) is derived for obtaining solutions to a class of elliptic boundar... more A Boundary Element Method (BEM) is derived for obtaining solutions to a class of elliptic boundary value problems (BVPs) of functionally graded media (FGM). Some particular examples are considered to illustrate the application of the BEM.