cover
Article Per Year (5 Year)
All
Home Page
OAI Link
Editorial Team
Contact
Reviewer
Google Scholar
Contact Name
-
Contact Email
ujm@mail.unnes.ac.id
Phone
-
Journal Mail Official
ujm@mail.unnes.ac.id
Editorial Address
Sekaran, Kec. Gn. Pati, Kota Semarang, Jawa Tengah 50229
Location
Kota semarang,
Jawa tengah
INDONESIA
Unnes Journal of Mathematics
Published by Universitas Negeri Semarang
ISSN : -     EISSN : 24605859     DOI : https://doi.org/10.15294/ujm
Core Subject : Education,
Education Mathematics
Unnes Journal of Mathematics is published by Universitas Negeri Semarang. This Journal receives and publishes research articles and development in mathematics theories and their applications.
Arjuna Subject : Matematika - Matematika (Lain-Lain)
Articles 15 Documents
 1   2 
Inflation Forecasting in Indonesia Using Lee’s Fuzzy Time Series Method Sari, Virgania
Unnes Journal of Mathematics Vol. 14 No. 1 (2025): Unnes Journal of Mathematics Volume 1, 2025
Publisher : Universitas Negeri Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/ujm.v14i1.14215

Abstract

Inflation is an important economic indicator, the rate of growth is should be low and stable. Unstable inflation will complicate people's decisions to consume, invest and produce which in turn will reduce economic growth. One of the effects of this inflation is slow economic growth. For this reason, the government needs to consider policies that can influence it. Bank Indonesia one of the policies to control inflation is monetary. Forecasting methods are used to help facilitate future planning and can be used as guidelines for decision making that can improve economic performance. Forecasting used is fuzzy time series Lee. The data used is monthly inflation data in Indonesia for the period January 2017-May 2022. The error rate used is MAPE which produces a very good MAPE value of 8,16%. Forecasting results for the next period, June 2022, amounted to 3,66%.
Predator-Prey Model in the Growth Phase of Rice Plants with Pest Control Using Pesticides Afaf Himmatul Ulum; Muh. Fajar Safaatullah
Unnes Journal of Mathematics Vol. 13 No. 1 (2024): Unnes Journal of Mathematics Volume 1, 2024
Publisher : Universitas Negeri Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/ujm.v13i1.15133

Abstract

In Indonesia, Rice is the primary food crop in Indonesia, with rice being the staple food for more than half of the population. However, pest infestations at each stage of rice growth pose a serious threat that can reduce crop yields. This study developed a predator-prey mathematical model to describe the interactions between rice plants at different growth stages, such as the vegetative, reproductive, and maturation phases, and three major pests: rice stem borers, brown planthoppers, and rats. The model also incorporates Pontryagin's maximum principle for optimal control through pesticide application. The method yields state and costate equations, which are solved using the fourth-order Runge-Kutta forward-backward sweep method with the assistance of Scilab 2024 software. The objective of this research is to examine the model, analyze its stability and controllability, and conduct numerical simulations. The results indicate that the model has a stable equilibrium point, suggesting that the system is controllable. The simulation shows that pesticide application is effective in controlling pests during all stages of rice growth. The populations of rice stem borers, brown planthoppers, and rats decrease significantly, with each pest population reduced to fewer than 10 individuals. These results demonstrate that pesticide use helps maintain ecological balance, and reduces pest damage to rice plants.
Regional Prioritization for Free Nutritious Food Programs through Social Data Integration and Public Sentiment Analysis Using K-Means and NLP Sanusi, Ratna Nur Mustika; Wijaya, Galih Kusuma; Harwanti, Nur Achmey Selgi
Unnes Journal of Mathematics Vol. 14 No. 1 (2025): Unnes Journal of Mathematics Volume 1, 2025
Publisher : Universitas Negeri Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/ujm.v13i2.25750

Abstract

This study evaluates Indonesia's Free Nutritious Food Program (MBG) through an innovative dual-method approach combining geospatial clustering and sentiment analysis. Cluster analysis of 38 provinces identified three distinct priority zones: high-priority (Eastern Indonesia), medium-priority (Central Indonesia), and low-priority (Java-Bali-West Sumatra), revealing significant regional disparities. Parallel sentiment analysis of 1,358 social media posts showed 76.6% negative perceptions dominated by food safety concerns ("poisoning," "toxic"), contrasting with 23.4% positive feedback highlighting nutritional benefits. The study makes three key contributions: First, it demonstrates the disconnect between regional needs and implementation quality. Second, it introduces an integrated monitoring framework combining cluster mapping with real-time sentiment tracking. Third, it proposes actionable solutions including a rapid-response task force and targeted communication strategies. These findings provide policymakers with evidence-based tools to simultaneously address geographical inequities and improve program execution in nutrition interventions.
A Data Mining Approach to Wage Inequality Analysis in Indonesia: A Clustering Study Using Fuzzy C-Means Harwanti, Nur Achmey Selgi; Hendikawati, Putriaji; Sanusi, Ratna Nur Mustika; Pratama, Alfian Adi
Unnes Journal of Mathematics Vol. 13 No. 2 (2024): Unnes Journal of Mathematics Volume 2, 2024
Publisher : Universitas Negeri Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/ujm.v13i2.25755

Abstract

This study aims to cluster Indonesian provinces based on the average wage structure of workers across 17 economic sectors using the Fuzzy C-Means (FCM) method. The wage data underwent preprocessing steps including missing value imputation using the median, logarithmic transformation to reduce skewness, and Z-Score standardization to ensure uniform data scaling. The evaluation of the number of clusters and fuzziness values was conducted using the Silhouette coefficient and Fuzzy Partition Coefficient (FPC), with the best results achieved at three clusters and a fuzziness value of 1.3. Further analysis using Principal Component Analysis (PCA) provided visualization of the clusters, while radar charts illustrated wage characteristics by sector within each cluster. The clustering results reveal significant economic disparities among provinces: Cluster 1 consists of provinces with the highest wages dominated by high-value-added sectors such as mining and finance; Cluster 0 shows a balanced wage distribution reflecting a transitional economy; and Cluster 2 includes provinces with the lowest wages facing structural challenges. These findings offer a comprehensive overview of regional economic diversity in Indonesia and can serve as a basis for policy-making aimed at more equitable economic development.
Modelling and Analysis Study Of Plastic Waste Flow Dynamics System Baihaqi, Muhamad Adzib
Unnes Journal of Mathematics Vol. 14 No. 1 (2025): Unnes Journal of Mathematics Volume 1, 2025
Publisher : Universitas Negeri Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/ujm.v13i2.25911

Abstract

Waste is closely related to people's lives today. There are various types of waste, including solid, liquid, and gas, as well as organic and inorganic waste. One of the most common types of waste generated by society is plastic waste. Plastic waste makes up a large portion of inorganic waste. One approach to recognizing the flow pattern of plastic waste is the population dynamics model. This model is considered one of the best approaches for understanding the flow of plastic waste. This process begins by creating several compartments involved in the flow of plastic waste, and then a transition diagram is formed. Next, a system of differential equations is created based on the transition diagram. This topic will also discuss the stability of the equilibrium point and numerical simulation for influential parameters.

Page 2 of 2 | Total Record : 15

 1   2 

Filter by Year

2024 2025


Reset
Filter By Issues
All Issue Vol. 14 No. 1 (2025): Unnes Journal of Mathematics Volume 1, 2025 Vol. 13 No. 2 (2024): Unnes Journal of Mathematics Volume 2, 2024 Vol. 13 No. 1 (2024): Unnes Journal of Mathematics Volume 1, 2024