cover
Contact Name
Agus Suryanto
Contact Email
ijma@ub.ac.id
Phone
+628123304843
Journal Mail Official
ijma@ub.ac.id
Editorial Address
Faculty of Mathematics and Natural Sciences, Brawijaya University. Jl. Veteran, Malang City, East Java, Indonesia
Location
Kota malang,
Jawa timur
INDONESIA
Indonesian Journal of Mathematics and Applications
Published by Universitas Brawijaya
ISSN : -     EISSN : 29868149     DOI : https://doi.org/10.21776/ub.ijma
Core Subject : Science, Education,
The Indonesian Journal of Mathematics and Applications is a journal managed by Universitas Brawijaya, Malang, Indonesia, that is published twice a year (in March and September). IJMA is devoted to research articles of the highest quality in all areas of mathematics and its applications, statistics, and data science. The journal covers the following topics: Mathematical Analysis, Algebra, Biomathematics, Industrial Mathematics, Operasion Research, and Optimization, Data Sciences/Soft computing, Mathematical Physics, Financial Mathematics and Actuarial Sciences, Statictics. Upon its submission, the Editor-in-Chief decides on the suitability of the paper’s content for the aim and scope of the IJMA. If the Editor in Chief considers the paper is suitable, then the paper will be sent for peer reviewing by two peer reviewers. The Indonesian Journal of Mathematics and Applications maintains double anonymity, so neither the peer reviewers nor the author(s) can be identified by one another. The peer reviewers are respected scholars in the areas. The Indonesian Journal of Mathematics and Applications is an open access, peer-reviewed journal that considers articles describing novel computational algorithms and software, models and tools, including statistical methods, machine learning, and artificial intelligence, as well as systems biology.
Articles 59 Documents
Clustering of Indonesian Provinces by Environmental Pollution in 2024 Using the K-Means Algorithm Ardiyani, Faradilla; Akmalia, Rizka
Indonesian Journal of Mathematics and Applications Vol. 3 No. 2 (2025): Indonesian Journal of Mathematics and Applications (IJMA)
Publisher : Universitas Brawijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21776/ub.ijma.2025.003.02.1

Abstract

The environment encompasses all living things and their surroundings, which interact to influence and sustain each other. In the era of globalization, advanced technologies have emerged that enhance human life, but these developments also have negative effects, such as environmental pollution. This research aims to categorize environmental pollution data in Indonesia, enabling further analysis of the clustering results. The study employs the K-Means algorithm to analyze data from 2024. This algorithm groups a set of objects into K clusters, with each object assigned to the nearest cluster based on average distance. The research findings indicate that the K-Means algorithm achieved a Silhouette Coefficient of 0.68 and identified two distinct clusters: Cluster 1 consists of 32 members characterized by lower numbers of environmental pollution while Cluster 2 includes 6 members that represent areas with greater environmental pollution. This study aims to provide the government with insights to address the rising issue of environmental pollution effectively.
p-Pompeiu-Hausdorff Metric on Space of Subsets Induced by Partial Metric Ekayanti, Arta; Marjono; Muslikh, Mohamad; Fitri, Sa’adatul
Indonesian Journal of Mathematics and Applications Vol. 3 No. 2 (2025): Indonesian Journal of Mathematics and Applications (IJMA)
Publisher : Universitas Brawijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21776/ub.ijma.2025.003.02.2

Abstract

In this paper, we give some properties of the p-Pompeiu-Hausdorff metric on the space of subsets induced by a partial metric. These results provide a generalization of Barich’s (2011) results in the setting of partial metric. The properties provided in this study complement those presented by Aydi et al (2012).
Implementation of Graph Coloring on the Map of North Gorontalo District Using the D’Satur Algorithm and the Backtracking Algorithm Imran, Nurain; Achmad, Novianita; Asriadi, Asriadi; Yahya, Nisky Imansyah; Nasib, Salmun K.; Katili, Muh Rifai
Indonesian Journal of Mathematics and Applications Vol. 3 No. 2 (2025): Indonesian Journal of Mathematics and Applications (IJMA)
Publisher : Universitas Brawijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21776/ub.ijma.2025.003.02.5

Abstract

Graph Coloring is the process of assigning colors to vertices such that no adjacent vertices share the same color, using the minimal number of colors possible. This study aims to implement graph coloring to the map of North Gorontalo Regency, which consists of 11 sub-districts and 123 villages, utilizing the D’Satur and Backtracking algorithms. It also compares the algorithms in terms of the smallest chromatic number and identifies strategic points in North Gorontalo Regency, particularly in sub-districts, based on the number of adjacent vertices. The study employed a case study method to gather information, specifically the map of North Gorontalo Regency. The results demonstrate that graph coloring of the map utilizing the D’Satur algorithm produces a chromatic number of (χ = 3) for sub-districts and (χ = 5) for villages. Meanwhile, the Backtracking algorithm yields a chromatic number of (χ = 3) for districts and (χ = 4) for villages. Thus, for sub-district coloring, both algorithms yield the same chromatic number. However, the Backtracking algorithm performs better for village coloring, as it produces the smallest chromatic number. The identified strategic sub-district is Kwandang, which has the highest degree of 4.
A Comparative Study of Finite Difference, Shooting, and Collocation Methods for Linear Non-Stiff, Stiff, and Nonlinear Two-Point Boundary Value Problems with Dirichlet and Neumann Boundary Conditions Kamelia, Sania; Muallimah, Annida; Nurkamila, Siti; Habibah, Ummu
Indonesian Journal of Mathematics and Applications Vol. 3 No. 2 (2025): Indonesian Journal of Mathematics and Applications (IJMA)
Publisher : Universitas Brawijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21776/ub.ijma.2025.003.02.4

Abstract

This study discusses the performance comparison of three numerical approaches, namely the Shooting method, the Finite Difference Method (FDM), and the Collocation method, in solving Boundary Value Problems (BVP) for three categories of problems: linear non-stiff, linear stiff, and non-linear. Each type of problem is tested with two types of boundary conditions, namely Dirichlet and Neumann. The evaluation is based on two main criteria: accuracy, measured using error norms with respect to the exact solution, and computational efficiency, quantified in terms of CPU execution time. The results show that in the non-stiff case with Dirichlet boundary conditions, the Shooting methods based on LSODA and RK5 provide very high accuracy with good efficiency, while the Finite Difference Method excels in efficiency but is slightly inferior in accuracy. Under Neumann boundary conditions, the Finite Difference Method tends to be less accurate, whereas the Collocation method delivers very good accuracy but with relatively lower efficiency. For stiff problems, the Shooting method maintains high accuracy, while the Finite Difference and Collocation methods show varying performance depending on the type of boundary condition. In the non-linear case, the Shooting method becomes the most accurate option, although with slightly lower efficiency compared to the Finite Difference Method. These findings provide practical guidance in selecting appropriate numerical methods for BVPs based on problem characteristics and boundary conditions.
Valuing Options of Indonesia Composite Index: A Comparative Analysis of Binomial and Black-Scholes Models Zahrah, Salsabila Az; Widyaningrum, Anisa Jannata; Rebika, Dinda Ayu Arsyil; Asshafwa, Ezzedine Humairo; Putri, Ivana Maharani
Indonesian Journal of Mathematics and Applications Vol. 3 No. 2 (2025): Indonesian Journal of Mathematics and Applications (IJMA)
Publisher : Universitas Brawijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21776/ub.ijma.2025.003.02.3

Abstract

In this research, the valuation of the Indonesia Composite Index (IHSG) option prices is examined through the implementation and comparison of two common models: the Binomial model and the Black–Scholes model. The incubation of this work is the caustic drop of IHSG on March 18, 2025, which not only stopped trading on the Indonesia Stock Exchange but also sent shock waves through the market. We therefore investigate how increased volatility and anxiety in the market affect option pricing. Secondary data of IHSG closing prices from April 2024 to March 2025. From this data, they calculated daily logarithmic returns, estimated the volatility, and got the key parameters for options. The analysis focuses on at-the- money European call and put options with a maturity period of three months, which were valued before and after the trading halt. The results of the research show that the two methods are consistent, both models predict considerably higher option values as a result of a volatility increase from 27.13% to 31.28%. The evidence shows that greater market uncertainty raises the time value of call and put options, resulting in higher premiums regardless of the underlying asset’s movement. Furthermore, the strong agreement between the Binomial and Black–Scholes valuations confirms the robustness of both modeling approaches. These findings highlight the critical role of volatility in shaping option prices within emerging markets and emphasize the dual function of options as instruments for both risk hedging and speculative opportunities during periods of market stress, such as the IHSG trading halt in March 2025.
Algebraic Analysis of The Encoding and Decoding Process of Goppa Code with Implementation in SageMath Rahwanto, Taufiq Hamid; Utomo, Putranto Hadi; Siswanto
Indonesian Journal of Mathematics and Applications Vol. 4 No. 1 (2026): Indonesian Journal of Mathematics and Applications
Publisher : Universitas Brawijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21776/ub.ijma.2026.004.01.2

Abstract

Error-Correcting Code (ECC) is one of the solutions that have been widely developed to overcome errors, with the aim of detecting and correcting errors that occur. Among the various types of ECC, Goppa code have proven to be effective in maintaining data integrity. This study focuses on examining how the algebraic structure of the Goppa code is utilized for ECC, thereby enabling an understanding of how elements in the field can be transformed into binary vectors and polynomials to construct the parity-check matrix and the generator matrix. The algebraic structure is then analyzed to determine whether it can be optimized to detect and correct errors in the encoding and decoding processes. Subsequently, a simple program will be developed using the SageMath programming language, followed by simulations. The simulation results are expected to optimize the error-correction capacity, thereby demonstrating an improvement in the error-correction capability of the Goppa code during the decoding process.
Graph Energy of Non-Coprime Graphs for Some Finite Non-abelian Groups Suleiman, Aliyu; Ibrahim Kiri, Aliyu; Tijjani, Bilkisu
Indonesian Journal of Mathematics and Applications Vol. 4 No. 1 (2026): Indonesian Journal of Mathematics and Applications
Publisher : Universitas Brawijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21776/ub.ijma.2026.004.01.3

Abstract

In this paper, we study the Laplacian energy and Seidel energy of the non-coprime graphs for the dihedral group $D_n$, $n \geq 3$, $n = p^r$, where $p$ is prime and $r \in \mathbb{Z}^+$, and the generalized quaternion $Q_{4n}$, $n \geq 2$. The investigation starts by obtaining the spectrum for the graphs and then generalizing the formulae for computing the respective energies. It is shown that the Seidel energy for the non-coprime graph for a dihedral group when $n = 2^r$, $r > 1$, is less than the Laplacian energy for the same graph; this is also true for the generalized quaternion. Furthermore, the Seidel energy for the non-coprime graph for a dihedral group $D_n$ when $n = 2^r$, $r > 1$, is the same as the adjacency energy of the same graph for the same group.
The existing huge volume of algebraic structures in the subject “ALGEBRA” has few serious hidden gaps and needs fixing in order to validate many of the elementary and important frequently practiced algebraic computations Biswas, Ranjit
Indonesian Journal of Mathematics and Applications Vol. 4 No. 1 (2026): Indonesian Journal of Mathematics and Applications
Publisher : Universitas Brawijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21776/ub.ijma.2026.004.01.4

Abstract

In this paper it is justified in full length that there is a genuine need for the giant subject ‘ALGEBRA’ to have a new but unique Algebraic Structure. Consequently, a new algebraic structure “Region” is introduced, and its properties are studied. This paper introduces a new algebraic structure called Region, providing a unified framework for interactions between internal multiplication and scalar multiplication commonly used in algebra. The novelty lies in combining field structure, vector space structure, and compatibility in a single framework. Without the algebraic structure “Region” the subject ‘ALGEBRA’ can not validate many elementary algebraic computations being frequently practiced by the mathematicians, researchers and students in their daily works in the last centuries; unbelievable and surprising, but it is true.
Topological Existence and Uniqueness of the Mahgoub–Adomian Decomposition Method Adepoju, Julius; Ajani, Abiodun Sufiat; Olubanwo, Oludapo Omotola; Onitilo, Sefiu Adekunle; Oduyemi, Oluwadamilare Segun
Indonesian Journal of Mathematics and Applications Vol. 4 No. 1 (2026): Indonesian Journal of Mathematics and Applications
Publisher : Universitas Brawijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21776/ub.ijma.2026.004.01.1

Abstract

We develop a rigorous topological theory for the Mahgoub--Adomian Decomposition Method (MADM) in the setting of Banach spaces. The method is formulated as a nonlinear operator equation in the space $C([0,T];H^s(\Omega))$, where the associated Mahgoub--Adomian operator is shown to be continuous and compact. Existence of the MADM solution is established via Schauder’s fixed-point theorem, while uniqueness follows under a strict monotonicity condition on the nonlinear operator. The analysis is carried out independently of contraction assumptions or smallness conditions. The  results are applied to both linear and nonlinear Schrödinger equations of the form $i u_t + \Delta u + N(u) = f(x,t), \quad u(x,0)=h(x)$, including the linear problems $N(u)=0$ and nonlinear problems such as $N(u)=\lambda |u|^{p}u$. These results provide a topological well-posedness framework that justifies the convergence and uniqueness of the Mahgoub--Adomian decomposition series for a broad class of Schrödinger-type evolution equations.