cover
Article Per Year (5 Year)
All
Home Page
OAI Link
Editorial Team
Contact
Reviewer
Google Scholar
Contact Name
I Ketut Resika Arthana, S.T., M.Kom
Contact Email
resika@undiksha.ac.id
Phone
-
Journal Mail Official
-
Editorial Address
-
Location
Kota denpasar,
Bali
INDONESIA
Jurnal Sains dan Teknologi
Published by Universitas Pendidikan Ganesha
ISSN : 23033142     EISSN : 25488570     DOI : -
Core Subject : Science, Education,
Computer Science & IT Education
Jurnal Sains dan Teknologi(JST) is a journal aims to be a peer-reviewed platform and an authoritative source of information. We publish original research papers, review articles and case studies focused on Mathematic, Biology, Physic, Chemistry, Informatic, Electronic and Machine as well as related topics. All papers are peer-reviewed by at least two referees. JST is managed to be issued twice in every volume.
Arjuna Subject : -
Articles 694 Documents
 64   65   66   67   68 
Evaluation of Hybrid KNN-Naïve Bayes Model using Cross Validation for Weather Prediction Saiful Andika S. S; Sugiyarto Surono; Aris Thobirin
JST (Jurnal Sains dan Teknologi) Vol. 14 No. 3 (2025): October
Publisher : Universitas Pendidikan Ganesha

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.23887/jst-undiksha.v14i3.91956

Abstract

The low accuracy of conventional weather prediction models is often hampered by the complexity of weather data that is dynamic, non-linear, and full of uncertainty. Therefore, it is necessary to evaluate hybrid models such as KNN-Naïve Bayes with cross-validation techniques to test their reliability and effectiveness in producing more accurate and consistent weather predictions. This study evaluates the effectiveness of the hybrid KNN-Naïve Bayes model for weather prediction using cross-validation techniques. Through an experimental quantitative approach, weather data from Kaggle was analyzed to compare the performance of the KNN, Naïve Bayes, and hybrid KNN-Naïve Bayes models. Data preprocessing methods include normalization and dataset partitioning with five variations of data sharing ratios. Model evaluation using 3-fold cross-validation shows that the hybrid KNN-Naïve Bayes model achieves the highest accuracy of 97.20% at ratios of 80:20 and 70:30, outperforming KNN with an accuracy of 96.27% and Naïve Bayes with 96.56%. The implications of this research indicate that the hybrid model can overcome the limitations of each algorithm, particularly in handling class imbalance and the assumption of feature independence. The results of the KNN-Naïve Bayes hybrid model research proved to be a superior alternative in weather prediction that can contribute to the development of a more reliable early warning system in the face of increasingly dynamic climate change. In conclusion, the application of the KNN-Naïve Bayes hybrid model with cross-validation techniques can improve the accuracy of weather prediction compared to the use of either method separately.
Koh Catalyst Concentration and Stirring Speed in The Transesterification Process on Biodiesel Yield from Spent Coffee Grounds Oil Desi Heltina; Fadrian Oktori; Amun Amri; Agustina Dumaria; Maria Peratenta Sembiring
JST (Jurnal Sains dan Teknologi) Vol. 15 No. 1 (2026): April
Publisher : Universitas Pendidikan Ganesha

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.23887/jst-undiksha.v15i1.92848

Abstract

Coffee grounds have a fairly high oil content in the seeds of around 15-20% which has great potential to be used as raw material for making biodiesel. This study aims to determine the physical characteristics of coffee grounds biodiesel; and to determine the effect of stirring speed, amount of catalyst and reaction time on the yield of coffee grounds biodiesel. The type of research on biodiesel production from coffee grounds waste is quantitative. The data collection method is carried out by experimenting on biodiesel that has been obtained from coffee grounds waste oil on the concentration of KOH catalyst, stirring speed and reaction time. After the required data has been collected, an analysis is carried out using a descriptive and analytical case study method. The result of the study obtained the best condition, namely at a KOH catalyst concentration of 3% wt oil, and a stirring speed of 800 rpm, a biodiesel yield of 30,19%. So it can be concluded that coffee grounds oil biodiesel has been successfully obtained and has met the quality standards of ASTM D6751 and EN 14214. The yield of biodiesel produced increased along with the increasing transesterification reaction time. GC-MS analysis showed that coffee grounds oil biodiesel was mostly composed of linoleic acid and palmitic acid. The implications of this research can be used in the development of further research related to innovations in improving environmentally friendly fuels based on organic waste.
Temperature Prediction Using BP-RVM with RBF and Polynomial Kernel Combination Alfian Rahman; Syaharuddin; Vera Mandailina; Pirda Aziza
JST (Jurnal Sains dan Teknologi) Vol. 14 No. 3 (2025): October
Publisher : Universitas Pendidikan Ganesha

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.23887/jst-undiksha.v14i3.95242

Abstract

The problem of this research stems from the low accuracy of conventional temperature prediction models in representing nonlinear patterns of complex and uncertain climate data. In addition, the utilization of kernel-based machine learning models is still not optimal in improving the accuracy of monthly temperature predictions. The main objective of this study is to analyze, evaluate, and validate the accuracy level of the Bayesian Relevance Vector Machine (BP-RVM) model with a combination of Radial Basis Function and Polynomial kernels in predicting monthly temperatures. This research is an experimental study with a training-testing design. The research subjects are monthly temperature data from Mataram City for the period 2013–2023, with 578 data as test subjects and data from 2023 as testing data. Data collection was carried out through secondary data documentation from NASA, with instruments in the form of temperature datasets processed using MATLAB. Data analysis uses Mean Squared Error (MSE) and Mean Absolute Percentage Error (MAPE). The results show that the BP-RVM model with the RBF-Polynomial kernel, especially with the trainrp algorithm, produces higher prediction accuracy than trainlm. The study's conclusions confirm that the combination of kernels in BP-RVM effectively improves the accuracy of temperature predictions. The implications of this research support the development of more reliable climate prediction models for the agriculture, energy, and tourism sectors.
Utilization of Technology in Learning Process Management in Industrial Engineering Vocational High Schools Warkianto Widjaja
JST (Jurnal Sains dan Teknologi) Vol. 14 No. 3 (2025): October
Publisher : Universitas Pendidikan Ganesha

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.23887/jst-undiksha.v14i3.97114

Abstract

The lack of use of technology media among industrial engineering students of vocational high schools. Multimedia elements are expected to provide innovation in the learning process with the support of components. However, the use of technological elements such as text and images sometimes hinders the learning process for both teachers and students. Urgent to be studied because there is a difference between expectations and reality in the field. The aim is to evaluate the use of technology components from three devices, namely Multimedia, digital and tablets and to determine the correlation of the three variables. The research approach is quantitative survey type. The number of samples is 127 people, namely industrial engineering students and teachers. Data collection techniques with instruments that have been developed from multimedia variable indicators, digital stories and tablets. The instrument is assessed based on a Likert scale from point 1 to point 5. The data analysis technique uses descriptive statistics assisted by SPSS Version 29.0, with validation tests, means, standard deviations and minimum values and correlations. The results found that the use of multimedia, digital, and tablets has high reliability and correlation as well as a positive and significant relationship to all variables in the evaluation. The findings confirm that the components in multimedia are in the high category and can be used in an effective learning process. The implications provide an overview for industrial engineering teachers and students to actively use multimedia as a learning process aid in the classroom.
The Effect of Eco-Enzymes on the Growth and Productivity of Vegetable Plants : Literature Review Aldo David Dora; R. Susanti; Talitha Widiatningrum
JST (Jurnal Sains dan Teknologi) Vol. 15 No. 1 (2026): April
Publisher : Universitas Pendidikan Ganesha

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.23887/jst-undiksha.v15i1.98952

Abstract

Eco-enzyme is an organic liquid produced by the fermentation of kitchen waste and crop residues that has great potential to address organic waste problems while increasing agricultural productivity sustainably. This innovation supports the reduction of household organic waste volume and the implementation of environmentally friendly agricultural systems. This study aims to evaluate the effect of ecoenzyme on the growth and productivity of vegetable plants. The method used in writing this literature review is a narrative review. Data search using electronic data sources, namely Garuda, Google Scholar, and Semantic Google Scholar. Then, the search found 15 articles. The results of the study indicate that the administration of ecoenzyme has a positive impact on the growth and productivity of vegetable plants. The optimal concentration of ecoenzyme was found in the range of 3% and 10 ml/L for growth, and 1.5 ml/L of water and 20 ml/L for productivity. Ecoenzyme increases soil fertility, improves soil structure, and encourages nutrient and water absorption by plant roots. In addition, the plant hormone content in ecoenzyme such as auxin, gibberellin, and cytokinin helps maximize vegetative growth, generative growth, and fruit ripening. Despite its many advantages, ecoenzymes take longer to show optimal results than inorganic fertilizers, so they are often used as a supplement in organic farming systems. To optimally meet plant nutritional needs, a combination of other organic fertilizers and good soil management practices is still necessary. Therefore, the use of ecoenzymes as a liquid organic fertilizer has been shown to improve the quality of vegetable crops, both in terms of growth, yield, and nutritional content.
Optimalisasi Pengendalian Pompa Air Sisa Produksi Berbasis PLC dengan Sensor Floatless Level Switch dan Sensor Redundansi untuk Pencegahan Luapan Air Tangki Industri Abdul Rohman Hakim; Junita; Herman Kanabele
JST (Jurnal Sains dan Teknologi) Vol. 14 No. 3 (2025): October
Publisher : Universitas Pendidikan Ganesha

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.23887/jst-undiksha.v14i3.99283

Abstract

Kinerja sistem kontrol pompa otomatis pada tangki penampungan air sisa produksi di area mesin pembuatan dinding ban mengalami penurunan efisiensi akibat kerusakan komponen dan keterbatasan mekanisme berbasis timer. Sistem lama tidak mampu merespons fluktuasi aliran air secara real-time, sehingga sering terjadi luapan tangki dan gangguan operasional. Penelitian ini bertujuan untuk menganalisis panel kontrol berbasis Programmable Logic Controller (PLC) yang terintegrasi dengan sensor floatless level switch dan sensor redundansi untuk mendeteksi level air secara presisi. Sistem dirancang dengan konfigurasi dual pump untuk memastikan keandalan operasi, penataan panel yang lebih rapi, serta fault alarm yang terhubung ke HMI utama. Penelitian menggunakan metode research and development dengan implementasi langsung pada tangki industri, disertai pengujian kinerja melalui simulasi dan pengukuran waktu siklus kerja pompa. Hasil implementasi menunjukkan penurunan signifikan insiden luapan tangki, efisiensi operasional meningkat dengan rata-rata waktu aktif pompa 2,52 menit dan waktu jeda 8,43 menit dan tidak adanya problem terkait air melebihi kapasitas tangki ataupun kerusakan pada sistem pompa yang tidak terdeteksi. Sistem baru terbukti lebih andal, efisien, dan mudah dipelihara dibanding sistem lama. Temuan ini berimplikasi pada peningkatan manajemen air industri sekaligus memperpanjang umur pakai pompa dan mengurangi risiko kerusakan lingkungan.
Development and Testing of an IoT-Based Yogurt Fermenter Prototype for MSMEs Septian Deny Widya Putra; Nuri Andarwulan; Dede Robiatul Adawiyah
JST (Jurnal Sains dan Teknologi) Vol. 15 No. 1 (2026): April
Publisher : Universitas Pendidikan Ganesha

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.23887/jst-undiksha.v15i1.100993

Abstract

Temperature is an important parameter in the yogurt fermentation process. MSME-scale yogurt fermenters currently available do not yet have an accurate temperature-control system. This study aims to develop an Internet of Things (IoT)-based yogurt fermenter prototype with a temperature-control system using the PID method. PID parameter determination was carried out using the modified Ziegler-Nichols and Chien-Hrones-Reswick tuning methods. The evaluation results showed that the PID parameters obtained from the Ziegler-Nichols method provided better temperature control performance than those from the CHR method, with lower rise time, settling time, and overshoot. The 8-hour fermentation test showed that the average fermenter temperature approached the target of 45°C, with minimal deviation. Increasing the fermentation temperature and adding rice flour increased the rate of pH decrease. This study shows that a PID-based control system can significantly improve the performance of MSME-scale yogurt fermenters, thereby increasing the competitiveness of the MSME-scale yogurt industry. This system implies that, in addition to being used as a yogurt fermenter, it can also serve other functions because it is essentially a water bath.
Precision-Optimized CNN for Indonesian Sign Language Recognition on Mobile Devices Mgs. Afriyan Firdaus; Tiara Dewangga; Dwi Rosa Indah; Rahmat Izwan Heroza; Juan Anthonius Kusjadi; Evandio Martin; Ayulia Putri Aisyah; Alexander; Fransiskus Xaverius Wikan Aji Narautama
JST (Jurnal Sains dan Teknologi) Vol. 14 No. 3 (2025): October
Publisher : Universitas Pendidikan Ganesha

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.23887/jst-undiksha.v14i3.101617

Abstract

Sign language recognition systems play a crucial role in bridging communication between individuals with hearing impairments and the general public; however, their development often faces challenges in balancing accuracy and computational efficiency on mobile devices. This study aims to design, implement, and evaluate a lightweight Convolutional Neural Network (CNN) model based on SSD MobileNet V2 to optimize the accuracy and efficiency of real-time Indonesian Sign Language (BISINDO) alphabet recognition on Android devices. This research adopts an applied experimental approach with a deep learning–based system development design. The research subjects consist of 3,878 hand gesture images collected from various contributors, representing 26 BISINDO alphabet letters with variations in hand size, skin tone, and gender. Data were collected through image acquisition and labeling using LabelImg, followed by analysis using transfer learning and performance evaluation via the TensorFlow Object Detection API. Data analysis involved measuring precision, accuracy, and model learning rate to assess system effectiveness. The results demonstrate that the proposed model achieved an average precision of 89% and a real-time recognition accuracy of 93%, outperforming the baseline MobileNetV3 model. These findings confirm that lightweight CNN architectures can provide an efficient and reliable solution for sign language recognition on low-power devices. Overall, this study concludes that the integration of deep learning and mobile technology can deliver inclusive innovations that expand communication accessibility for individuals with hearing disabilities. The implications of this research highlight the importance of developing user-friendly artificial intelligence–based systems that support digital equity in educational and social contexts.
Temperature Control System Using Carbon Fiber Filament Based on PID Control for Rabbit Hutches Wincoko
JST (Jurnal Sains dan Teknologi) Vol. 14 No. 3 (2025): October
Publisher : Universitas Pendidikan Ganesha

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.23887/jst-undiksha.v14i3.101909

Abstract

Rabbits are highly sensitive to temperature fluctuations, particularly during the neonatal phase when thermoregulatory mechanisms are not yet fully developed. Unstable environmental temperatures can induce thermal stress, reduce feed intake, inhibit growth, and increase mortality rates. This study aims to design and evaluate a temperature control system based on a Proportional–Integral–Derivative (PID) controller integrated with a carbon fiber filament heating element for rabbit kits housing, and to compare its performance with a conventional heating system. An experimental–applied approach was employed using a Completely Randomized Design (CRD), involving two treatments: carbon fiber heating with PID control and conventional heating with an on–off thermostat. Data collected included real-time cage temperature, energy consumption (kWh), rabbit welfare indicators (feed intake, respiration rate, and mortality), as well as qualitative data obtained through observation and farmer interviews. Quantitative analysis was conducted using descriptive statistics, ANOVA, Root Mean Square Error (RMSE), and Integral of Absolute Error (IAE), while qualitative data were analyzed thematically. The results demonstrate that the PID–carbon fiber system maintained temperature stability with an average deviation of 0.12 °C, significantly outperforming the control system (1.45 °C). Energy consumption was reduced by 23%, feed intake increased by 21%, respiration rate decreased by 16%, and mortality was lower under the PID-based system. The discussion highlights that the integration of carbon fiber filament heating with PID control enhances energy efficiency, ensures homogeneous heat distribution, and improves overall rabbit welfare. In conclusion, this system shows strong potential to reduce operational costs by up to 30% while increasing productivity, although challenges related to humidity effects on filament durability warrant further investigation.
Analysis of Public Perception of Canggu Village Infrastructure Facilities as a Tourist Destination AAA Cahaya Wardani; Yudi Arimbawa; Made Novia Indriani; Cokorda Putra
JST (Jurnal Sains dan Teknologi) Vol. 15 No. 1 (2026): April
Publisher : Universitas Pendidikan Ganesha

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.23887/jst-undiksha.v15i1.102155

Abstract

Canggu Village has undergone significant changes as a tourist destination. Changes in land use patterns influenced by tourism since the 1990s have affected the community's economic development. This study analyses community perceptions of the village's tourism spatial infrastructure. This study aims to analyse community perceptions of the infrastructure facilities in Canggu Village as a tourist destination. Using a mixed-methods embedded approach, this study combines qualitative and quantitative methods, with 50 pentahelix respondents selected through purposive sampling. Data collection was conducted through observation, in-depth interviews, documentation, and the distribution of questionnaires. The results show that the spatial infrastructure in Canggu Village is in the fairly good category, with an average value above 3.47 on a 5-point scale for most measured indicators. Community perceptions of the current condition of infrastructure facilities in Canggu Village generally indicate quite good results across basic, social, and economic infrastructure. However, it cannot be denied that tourism also brings its own challenges to the conditions in the Canggu area, where infrastructure development contributes to environmental degradation. This research implies that strategic and sustainable infrastructure development is a key factor in strengthening the competitiveness of tourist destinations and improving the community's economy as a whole.

Page 66 of 70 | Total Record : 694

 64   65   66   67   68 

Filter by Year

2012 2026


Reset
Filter By Issues
All Issue Vol. 15 No. 1 (2026): April Vol. 14 No. 3 (2025): October Vol. 14 No. 2 (2025): July Vol. 14 No. 1 (2025): April Vol. 13 No. 3 (2024): Oktober Vol. 13 No. 2 (2024): July Vol. 13 No. 1 (2024): April Vol. 12 No. 3 (2023): Oktober Vol. 12 No. 2 (2023): July Vol. 12 No. 1 (2023): April Vol. 11 No. 2 (2022) Vol 11, No 1 (2022) Vol. 11 No. 1 (2022) Vol 10, No 2 (2021) Vol. 10 No. 2 (2021) Vol 10, No 1 (2021) Vol. 10 No. 1 (2021) Vol 9, No 2 (2020) Vol. 9 No. 2 (2020) Vol. 9 No. 1 (2020) Vol 9, No 1 (2020) Vol. 8 No. 2 (2019) Vol 8, No 2 (2019) Vol 8, No 1 (2019) Vol. 8 No. 1 (2019) Vol. 7 No. 2 (2018) Vol 7, No 2 (2018) Vol. 7 No. 1 (2018) Vol 7, No 1 (2018) Vol 6, No 2 (2017) Vol. 6 No. 2 (2017) Vol. 6 No. 1 (2017) Vol 6, No 1 (2017) Vol 5, No 2 (2016) Vol. 5 No. 2 (2016) Vol 5, No 1 (2016) Vol. 5 No. 1 (2016) Vol. 4 No. 2 (2015) Vol 4, No 2 (2015) Vol 4, No 1 (2015) Vol. 4 No. 1 (2015) Vol 3, No 2 (2014) Vol. 3 No. 2 (2014) Vol 3, No 1 (2014) Vol. 3 No. 1 (2014) Vol 2, No 2 (2013) Vol. 2 No. 2 (2013) Vol 2, No 1 (2013) Vol. 2 No. 1 (2013) Vol 1, No 2 (2012) Vol. 1 No. 2 (2012) Vol 1, No 1 (2012) Vol. 1 No. 1 (2012) More Issue