Followed Journals
Journal you Follow: 0
Sign Up to follow journals, search in your chosen journals and, optionally, receive Email Alerts when new issues of your Followed Journals are published.
Already have an account? Sign In to see the journals you follow.
Similar Journals
Journal Cover
Jurnal Fourier
Number of Followers: 1  

  This is an Open Access Journal Open Access journal
ISSN (Print) 2252-763X - ISSN (Online) 2541-5239
Published by UIN Sunan Kalijaga Yogyakarta Homepage  [7 journals]
  • Aplikasi Spherical Trigonometry dalam Menentukan Arah Kiblat Umat Islam

    • Authors: Churun Lu'lu'il Maknun
      Abstract: Matematika banyak diterapkan di berbagai bidang keilmuan, seperti sains, teknologi, ekonomi termasuk dalam bidang agama. Salah satu penerapan penting matematika dalam agama khususnya agama Islam adalah dalam menentukan arah kiblat. Hal ini penting karena kondisi permukaan bumi yang terus berubah akibat pergeseran lempeng sehingga arah kiblat secara kontinu akan terus dilakukan. Hasil dan pembahasan dalam artikel ini diperoleh melalui kajian literatur dengan cara mengkonstruksi definisi dan teorema yang berkaitan dengan bentuk permukaan bumi, dan perhitungan geometris pada elipsoid. Dengan menggunakan prinsip geometri bola, segitiga bola dan trigonometri bola yang mencerminkan bentuk bumi yang berupa ellipsoid dapat dirumuskan cara menghitung arah kiblat untuk setiap daerah di permukaan bumi, yaitu dengan menggunakan aturan kosinus sebagai berikut: cos B= (cos b - cos a cos c)/sin a sin c. Selain itu disajikan pula bagaimana penggunaan rumus tersebut dengan menerapkan teknologi Google Earth dalam contoh konkrit penentuan arah kiblat dari suatu kota di Indonesia ke Kabah. Ketepatan penentuan koordinat lokasi menjadi penentu presisi dari sudut arah kiblat. [There are numerous applications of mathematics in other fields such as science, technology, economics and religion. One of the most important application of mathematics in religion is its use in deciding the direction of Kaaba for Moslem. This problem is important since the earth surface periodically changes due to the tectonic shift. The result of this study retrieved from literature study by constructing both the definitions and theorems of earth surface and geometrics calculation on ellipsoid. Using the spherical geometry, spherical trigonometry, and spherical triangle the formula to calculate the angle of Kaaba direction from particular point was constructed as follows: cos B= (cos b - cos a cos c)/sin a sin c. Further, the explanation of how to use and calculate the formula was also presented in this paper using the asssistance of Google earth technology. To sum up, the precision of coordinate of location becames main factor to obtain exact angle.]
      PubDate: 2021-10-31
      Issue No: Vol. 10, No. 2 (2021)
  • Probabilistic Inventory Model Using All Unit Discount Factor and Inflation

    • Authors: Mohammad Soleh, Arinal Haque, Yuslenita Muda
      Abstract: Inflation causes the price per unit of goods to rise in the future. To offset inflation, companies can take advantage of discounts provided by suppliers. But ordering goods must be adjusted according to demand to avoid storage costs. This study describes a probabilistic supply model with demand at a time with a Gamma distribution and waiting for the discount and inflation factors. Backorder conditions in this model is assumed. The research produces a probabilistic inventory model and an algorithm to obtain the optimal number of orders and optimal ordering times for items that are all discounted and inflated with Gamma distribution demand.
      PubDate: 2021-10-31
      Issue No: Vol. 10, No. 2 (2021)
  • A Mathematical Model of Microplastic Spreading into Fish Digestive Based
           On Abiotic Factor

    • Authors: Zani Anjani Rafsanjani HSM, Nurul Suwartiningsih, Ichsan I Luqmana
      Abstract: In this research, we observe the fish from seven different river location on Yogyakarta by evaluating its digestive weight. We investigate the microplastics spreading on fish digestive based on the abiotic factor such as river temperature, acidity, and river flow microplastics granules to be carried into the digestive tract of the fish. The rate of microplastics in the fish body can be describe mathematically using differential equation. We build a model based on the diagram flow of the relationship between each variables. Thus we have a differential system as the model. In the next step we analyze the model analytically. To show the accurancy of the model, we make a simulation using data simulation to the system and we compare it with the computing results using observation data. At the end of our research, we give a justification for the most influential abiotic factor for microplastic sreading.
      PubDate: 2021-10-31
      Issue No: Vol. 10, No. 2 (2021)
  • Mathematical Model, Stability Analysis and Numerical Simulations for The
           Spread of Malaria Disease in Yogyakarta City, Indonesia

    • Authors: Prihantini Prihantini
      Abstract: Indonesia is a country with frequent malaria cases. Therefore, a mathematical model is needed to model the distribution of malaria. The purpose of this study is to create a model with susceptible, infected, dormant and recovered compartments and to see the results of the simulation performed using maple 18 software. From the simulation results, it can be concluded that there is a decrease in the infected population and an increase in the recovered population over time.
      PubDate: 2021-10-31
      Issue No: Vol. 10, No. 2 (2021)
  • Matematika dalam Studi Keislaman (Metodelogi Penelitian Matematika yang

    • Authors: Mohammad Farhan Qudratullah
      Abstract: .
      PubDate: 2021-10-31
      Issue No: Vol. 10, No. 2 (2021)
School of Mathematical and Computer Sciences
Heriot-Watt University
Edinburgh, EH14 4AS, UK
Tel: +00 44 (0)131 4513762

Your IP address:
Home (Search)
About JournalTOCs
News (blog, publications)
JournalTOCs on Twitter   JournalTOCs on Facebook

JournalTOCs © 2009-