https://ejournal2.undip.ac.id/index.php/jfma/issue/feedJournal of Fundamental Mathematics and Applications (JFMA)2020-06-10T17:09:28+07:00Sutrisnos.sutrisno@live.undip.ac.idOpen Journal Systems<p><img style="float: left; padding-right: 15px;" src="/public/site/images/tresno_math/Cover_JFMA_kosongan.jpg" alt="Cover JFMA" width="150" align="left" /></p><p>Journal of Fundamental Mathematics and Applications (JFMA) is an Indonesian journal published by the Department of Mathematics, Diponegoro University, Semarang, Indonesia. JFMA has been published regularly in 2 scheduled times (June and November) every year. JFMA is established to highlight the latest update of mathematical researches in both theoretical and applied works. The scope in JFMA is pure mathematics and applied mathematics. All accepted papers will be published both in print and online versions. The online version can be accessed via the DOI link of each article. The print version can be ordered to the journal administrator.</p><p> </p><p>JFMA welcomes both theoretical and applied research work to be published in the journal. The topics include but are not limited to: (1) Mathematical analysis and geometry (2) Algebra and combinatorics (3) Discrete Mathematics (4) Mathematical physics (5) Statistics (6) Numerical method and computation (7) Operation research and optimization (8) Mathematical modeling (9) Mathematical Logic in Computer Science, Informatics, etc. More information, please go to: <a href="/index.php/jfma/about" target="_self">ABOUT JFMA</a> </p><p> </p><p> </p><p> </p><p><img style="float: left; padding-right: 15px;" src="/public/site/images/tresno_math/sinta_41.jpg" alt="JFMA Sinta 4" width="150" align="left" /></p><p>JFMA is accredited by the Directorate of Higher Education (DIKTI), Indonesia decree No. 36/E/KPT/2019. JFMA is categorized as SINTA 4. <span>Sinta (Science and Technology Index) was initiated in 2016 by the Director General of Strengthening Research and Development, Ministry of Research Technology and Higher Education of the Republic of Indonesia, with the involvement of experts from various institutions. </span>Sinta is made for delivering access to citations and expertise in Indonesia. Web-based research information system offering fast access, easy and comprehensive to measure the performance of researchers, institutions and journals in Indonesia. For more information, go to <a href="http://sinta.ristekbrin.go.id/" target="_blank">http://sinta.ristekbrin.go.id/</a></p><p> </p><p> </p><p>Journal template (.doc /.tex), accreditation certificate, copyright transfer form, etc. can be downloaded via link <a href="/index.php/jfma/pages/view/DOWNLOAD" target="_self">DOWNLOAD</a>.</p>https://ejournal2.undip.ac.id/index.php/jfma/article/view/7672KARAKTERISASI MODUL CYCLICALLY PURE (CP)-INJEKTIF2020-06-10T14:50:47+07:00Nia Yuliantinia.yulianti@stsn-nci.ac.idHanni Garminia Ynia.yulianti@stsn-nci.ac.id<p>This research deals with the structure of cyclically pure injective modules over a commutative ring R. If I be an ideal of R, proved that any CP-injective R/I<br />modul is also CP-injective as an R-module. The main result of research is the existance of CP-injective R-module if there is an R-module. More over, we deal characterization of CP-injective module which is related to proper essential ctclically pure extension. It is shown that R-modul D is cyclically pure injective if and only if D has no proper essential cyclically pure extension.</p>2020-06-10T13:31:10+07:00Copyright (c) 2020 Journal of Fundamental Mathematics and Applications (JFMA)https://ejournal2.undip.ac.id/index.php/jfma/article/view/7412COPRIME GRAPH OF INTEGERS MODULO n GROUP AND ITS SUBGROUPS2020-06-10T14:50:45+07:00Rina Julianarina.juliana@unram.ac.idMasriani Masrianimasriani@unram.ac.idI Gede Adhitya Wisnu Wardhanaadhitya.wardhana@unram.ac.idNi Wayan Switrayniniwayan.switrayni@unram.ac.idIrwansyah Irwansyahirw@unram.ac.id<p>Coprime Graph is a geometric representation of a group in the form of undirected<br />graph. The coprime graph of a group G, denoted by $\Gamma_G$ is a graph whose vertices are all elements of group G; and two distinct vertices a and b are adjacent if and only if $(|a|,|b|)=1$. In this paper, we study coprime graph of integers modulo n group and its subgroups. One of the results is if n is a prime number, then coprime graph of integers modulo n group is a bipartite graph.</p>2020-06-10T13:31:11+07:00Copyright (c) 2020 Journal of Fundamental Mathematics and Applications (JFMA)https://ejournal2.undip.ac.id/index.php/jfma/article/view/7411FUNGSI WRIGHT SEBAGAI SOLUSI ANALITIK PERSAMAAN DIFUSI-GELOMBANG FRAKSIONAL PADA MEDIA VISKOELASTIS2020-06-10T14:52:15+07:00Ray Novita Yasaray.novita@stsn-nci.ac.idAgus Yodi Gunawanray.novita@stsn-nci.ac.id<p>A fractional diffusion-wave equations in a fractional viscoelastic media can be constructed by using equations of motion and kinematic equations of viscoelastic<br />material in fractional order. This article concerns the fractional diffusion-wave equations in the fractional viscoelastic media for semi-infinite regions that satisfies signalling boundary value problems. Fractional derivative was used in Caputo sense. The analytical solution of the fractional diffusion-wave equation in the fractional viscoelastic media was solved by means of Laplace transform techniques in the term of Wright function for simple form solution. For general parameters, Numerical Inverse Laplace Transforms (NILT) was used to determine the solution.</p>2020-06-10T13:31:11+07:00Copyright (c) 2020 Journal of Fundamental Mathematics and Applications (JFMA)https://ejournal2.undip.ac.id/index.php/jfma/article/view/7413SOME PROPERTIES OF COPRIME GRAPH OF DIHEDRAL GROUP D_2n WHEN n IS A PRIME POWER2020-06-10T17:09:28+07:00Abdul Gazir Sabdgazirsyazir@gmail.comI Gede Adhitya Wisnu Wardhanaadhitya.wardhana@unram.ac.idNi Wayan Switrayniniwayan.switrayni@unram.ac.idQurratul Ainiqurratul.aini@unram.ac.id<p>The Study of algebraic structures, especially on graphs theory, leads to a<br />new topics of research in recent years. In this paper, the algebraic structures that will be represented by a coprime graph are the dihedral group and its subgroups. The coprime graph of a group G, denoted by \Gamma_D_2n is a graph whose vertices are elements of G and two distinct vertices a and b are adjacent if only if (|a,|b|)=1. Some properties of the coprime graph of a dihedral group D_2n are obtained. One of the results is if n is prime then \Gamma_D_2n is a complete bipartite graph. Moreover, if n is the power of prime then \Gamma_D_2n is a multipartite graph.</p>2020-06-10T13:31:11+07:00Copyright (c) 2020 Journal of Fundamental Mathematics and Applications (JFMA)https://ejournal2.undip.ac.id/index.php/jfma/article/view/7415EASY ENSEMMBLE WITH RANDOM FOREST TO HANDLE IMBALANCED DATA IN CLASSIFICATION2020-06-10T14:52:19+07:00Sarini Abdullahsarini@sci.ui.ac.idGV Prasetyosarini@sci.ui.ac.id<p>Imbalanced data might cause some issues in problem definition level, algorithm level, and data level. Some of the methods have been developed to overcome this issue, one of state-of-the-art method is Easy Ensemble. Easy Ensemble was claimed can improve model performance to classify minority class, and overcome the deficiency of random under- sampling. In this paper we discussed the implementation of Easy Ensemble with Random Forest Classifiers to handle imbalance problem in credit scoring case. This combination method is implemented in two datasets which taken from data science competition website, finhacks.id and kaggle.com with class proportion within majority and minority is 70:30 and 94:6. The results showed that resampling with Easy Ensemble can improve Random Forest classifier performance upon minority class. Recall on minority class increased significantly after the resampling. Before resampling, the recall on minority class for the first dataset (finhacks.id) was 0.49, and increased to 0.82 after the resampling. Similar results were obtained for the second data set (kaggle.com), where the recall for the minority class was increased from just 0.14 to 0.73.</p>2020-06-10T13:31:11+07:00Copyright (c) 2020 Journal of Fundamental Mathematics and Applications (JFMA)https://ejournal2.undip.ac.id/index.php/jfma/article/view/7874RUANG BERNORMA LENGKAP ATAS OPERATOR LINEAR TERBATAS PADA RUANG FUNGSI TERINTEGRAL DUNFORD2020-06-10T14:52:20+07:00Solikhin Solikhinsolikhin@live.undip.ac.idYD Sumantoydsumanto@lecturer.undip.ac.idAbdul Azizabdulaziz@lecturer.undip.ac.idSusilo Hariyantosusilohariyanto@lecturer.undip.ac.idR. Heri Soelistyo Utomorobertusherisoelisty@lecturer.undip.ac.id<p>Abstract. We are discussed operator norms on space of Dunford integral function. We show that sets of all bounded linear operator from dual space of Banach space into space of Lebesgue integral function is Banach space.</p><p> </p><p>Abstrak. Artikel ini membahas norma operator atas operator linear terbatas pada ruang fungsi terintegral Dunford. Himpunan semua operator linear dari ruang dual atas ruang Banach ke ruang fungsi terintegral Lebesgue merupakan ruang bernorma yang lengkap terhadap norma operator yang diberikan.</p>2020-06-10T13:31:12+07:00Copyright (c) 2020 Journal of Fundamental Mathematics and Applications (JFMA)https://ejournal2.undip.ac.id/index.php/jfma/article/view/7414ANALISIS TARIF PREMI DAN ASUMSI LOADING PADA PRODUK ASURANSI DWIGUNA BEASISWA2020-06-10T14:52:22+07:00Ira Rosianal Hikmahira.rosianal@stsn-nci.ac.idYulial Hikmahyulialhikmah47@ui.ac.id<p class="Abstract">Based on data from Badan Pusat Statistik (BPS), the number of Indonesia's population has consistently increased every year. This will cause several problems, one of them is public health. Health problems that occur cause some risks that cause losses. Therefore, one way to reduce the impact of these risks is insurance. This study analyzes how the process of forming premium prices with loading assumptions that are in accordance with existing assumptions in order to meet the criteria of equitable to the client, deliverable by the agent, and profitable to the company. This research uses a quantitative research approach. The population in this study was all Sum Insured (SI) while the sample was 1000 SI male sex. The data used in this study are secondary data that is data from an ABC insurance company in Indonesia, literature study through books, journal references, and previous research. The results of this study are the calculation of premiums by the methods used by the company more efficiently when compared with formulas in accordance with the theory. Although the price of a premium is more expensive using the company method, it is not significantly different. If using the company method, the sum insured used is the sum insured from death benefit whereas the theory is the average of claims incurred at that age. The fees charged are still fairly reasonable in accordance with the rules of setting the price of insurance premiums. In addition, the use of CSO 80 tables and Reinsurance Rates that have been adjusted to the company's interest rate of 5% in accordance with the expected cash value desired by the company.</p>2020-06-10T13:31:12+07:00Copyright (c) 2020 Journal of Fundamental Mathematics and Applications (JFMA)https://ejournal2.undip.ac.id/index.php/jfma/article/view/7765RELASI GREEN PADA GAMMA-SEMIGRUP YANG DIBANGKITKAN DARI SUATU SEMIGRUP2020-06-10T14:52:24+07:00YD Sumantoydsumanto@lecturer.undip.ac.idAbdul Azizabdulaziz@lecturer.undip.ac.idSolikhin Solikhinsolikhin@lecturer.undip.ac.idR. Heri Soelistyo Utomorobertusherisoelisty@lecturer.undip.ac.idIn the Gamma-semigroup generated from a semigroup, we can define some equivalence relations called the Green relation. Furthermore, we can examine the relationship between the Green relation on the Gamma-semigroup and the Green relation on it’s generating semigroup.2020-06-10T13:31:12+07:00Copyright (c) 2020 Journal of Fundamental Mathematics and Applications (JFMA)https://ejournal2.undip.ac.id/index.php/jfma/article/view/7416NUMERICAL SIMULATION OF STOCHASTIC DIFFERENTIAL EQUATIONS USING IMPLICIT MILSTEIN METHOD2020-06-10T14:52:26+07:00Ratna Herdianaratnaherdiana@lecturer.undip.ac.idStiff stochastic differential equations arise in many applications including in the area of biology. In this paper, we present numerical solution of stochastic differential equations representing the Malthus population model and SIS epidemic model, using the improved implicit Milstein method of order one proposed in [6]. The open source programming language SCILAB is used to perform the numerical simulations. Results show that the method is more accurate and stable compared to the implicit Euler method.2020-06-10T13:31:12+07:00Copyright (c) 2020 Journal of Fundamental Mathematics and Applications (JFMA)