cover
Contact Name
-
Contact Email
sainteknol_lp2m@mail.unnes.ac.id
Phone
-
Journal Mail Official
sainteknol_lp2m@mail.unnes.ac.id
Editorial Address
Sekaran, Kec. Gn. Pati, Kota Semarang, Jawa Tengah 50229
Location
Kota semarang,
Jawa tengah
INDONESIA
Sainteknol : Jurnal Sains dan Teknologi
ISSN : -     EISSN : 25273604     DOI : https://doi.org/10.15294/sainteknol
Core Subject : Education,
Sainteknol published a scientific paper on the results of research and studies in the field of science and technology. Published biannually in June and December contained the writings lifted from the results of research and critical-analysis study in science and technology.
Arjuna Subject : Umum - Umum
Articles 18 Documents
Design of ACS712-based Current Sensing Monitoring Evaluation for PWM Solar Charge Controller Wibowo, Apriansyah; Jayendra, I Gede Bagus; Utari, Dhea Yunita; Rasyiid, Muhammad; Aprilianto, Rizky Ajie
Sainteknol : Jurnal Sains dan Teknologi Vol. 22 No. 2 (2024): December 2024
Publisher : Universitas Negeri Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/sainteknol.v22i2.20604

Abstract

The rise of renewable energy has led to growing interest among researchers in optimizing renewable energy systems to harvest the highest possible energy output, especially in photovoltaic (PV) systems. Photovoltaic systems generate energy from sunlight, but the intermittent nature of sunlight poses a challenge for providing constant power. Another problem is that the most affordable conventional Pulse-Width Modulation (PWM) controllers on the market are unable to provide a current monitoring system. This issue is critical when users require detailed data to perform diagnostics on their PV systems. In this study, a monitoring system using microcontrollers and the ACS712 current sensor was developed and implemented to observe the behavior and performance of a photovoltaic (PV) charging system based on the current output from a PWM controller. The primary objective of this system is to develop a solution that can identify PV modules operating under suboptimal conditions, which can be caused by various factors such as increased solar cell temperature, cloud cover effects, PV module degradation, and the performance of the Pulse-Width Modulation (PWM) solar charge controller (SCC). This is crucial because PV modules can be susceptible to various environmental and technical factors that may impact their efficiency and power output. By closely monitoring the performance of each PV module using the ACS712-based current sensing system, the researchers aim to promptly detect and address any issues that may arise, ensuring the overall optimal operation of the PV system.
Comparison of the Use of YOLOv11 Variations in the Empty Parking Spaces Detection System Waskito, Deswal; Syarifah, Dian Farah; Aprilianto, Rizky Ajie
Sainteknol : Jurnal Sains dan Teknologi Vol. 23 No. 1 (2025): June 2025
Publisher : Universitas Negeri Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/sainteknol.v23i1.20014

Abstract

The development of a smart parking system using the You Only Look Once (YOLO) model has improved the efficiency of parking management by providing real-time vehicle detection and availability of parking spaces. This study compared three variations of YOLOv11-Nano (YOLOv11n), YOLOv11-Small (YOLOv11s), and YOLOv11-Medium (YOLOv11m) to determine the most effective model in detecting empty parking spaces. The experiment was carried out using a dataset consisting of 5725 images of parking areas with various conditions such as angles, lighting, and distance. In addition, the researcher also used a 6-second parking lot timelapse video for the test material of the model that had been trained. The results show that each variation of YOLOv11 has its own advantages in terms of accuracy, speed, and computing efficiency. YOLOv11n offers faster detection with lower resource consumption, while YOLOv11m provides higher accuracy with longer processing times. The findings of this study aim to help select the optimal YOLOv11 variant for smart parking implementation, thereby improving efficiency and accuracy in real-world applications.
Implementation of Hierarchy Attribute-Based Encryption (HABE) to Secure Information Stored in Cloud Storage Arfriandi, Arief; Gernowo, Rahmat; Isnanto, R. Rizal
Sainteknol : Jurnal Sains dan Teknologi Vol. 23 No. 1 (2025): June 2025
Publisher : Universitas Negeri Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/sainteknol.v23i1.22239

Abstract

The usage of cloud storage is currently growing, particularly for media used for information storage. Information saved in cloud storage makes it possible for the owner of the cloud storage to access the Information without the owner's permission. The privacy of access and management of access to the information kept in the cloud storage becomes a problem and security risk when using that cloud storage because the owner cannot ensure that the stored information is only accessed by authorized parties. Access control management is necessary for information owners to guarantee the safety of the information they hold. To regulate access to information kept in cloud storage, this study intends to apply the Hierarchy Attribute-Based Encryption (HABE) technique. A hierarchical attribute base is used to encrypt and decode information saved in cloud storage through the application of HABE, making hierarchical attributes the essential element in controlling access to the information. The hierarchical structure utilized to manage access control for information security will also be detailed in this research. This implementation procedure is completed before the information is stored in cloud storage. The mathematical computations used to secure text information during the encryption and decryption operations are described in the HABE implementation method and debate. By using Hierarchy Attribute-Based Encryption, security concerns with cloud storage can be resolved and flexible access control management in compliance with corporate standards is made possible.  
Cron Job Implementation for Automated Data Processing and Transfer in Cloud Infrastructure Wibowo, Apriansyah; Fathimah, Aisya; Waskito, Deswal; Aprilianto, Rizky Ajie
Sainteknol : Jurnal Sains dan Teknologi Vol. 23 No. 1 (2025): June 2025
Publisher : Universitas Negeri Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/sainteknol.v23i1.22649

Abstract

The rapid growth of cloud computing has necessitated efficient and automated solutions for data management in cloud infrastructure. Manual data processing and transfer methods are prone to delays, errors, and inefficiencies, particularly in real-time applications. This study proposes a systematic approach to automate data processing and transfer using cron job, PHP script logic, and Cloud Panel integration. A MySQL database was designed with two tables: data_now for real-time data and data_one_hour for scheduled transfers at one-hour intervals. Php script were developed to automate data transfer logic, while cron job were configured on the Cloud Panel to execute these scripts at predefined intervals. The system was tested in a cloud environment, demonstrating error-free, hourly data transfers with significant improvements in efficiency, accuracy, and timeliness. Results showed that the automated system reduced manual workload, ensured real-time data consistency, and optimized resource utilization. This study provides a scalable and reliable framework for automating data workflows in cloud-based systems, offering practical solutions for industries such as healthcare, finance, and IoT. The findings contribute to the field of cloud automation by presenting a robust approach that can be readily implemented across various organizational infrastructures.
Formulation and Characterization of Urea Slow-Release Fertilizer Based on Disposable Diaper Waste with Activated Carbon as Additives Kusumaningrum, Maharani; Rengga, Wara Dyah Pita; Hibatullah, Ridwan Dani; Nanggala, Pragusti Lintang Adhi; Ichwan, Rizky; Nada, Athiya Rihadatul ‘Aisy Qothrun
Sainteknol : Jurnal Sains dan Teknologi Vol. 23 No. 1 (2025): June 2025
Publisher : Universitas Negeri Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/sainteknol.v23i1.24961

Abstract

Disposable diapers are non-biodegradable waste that can pollute the environment. Disposable diapers contain super absorbent polymer (SAP) which has an absorption capacity of up to 1,000 times. SAP can be combined with activated carbon as a coating agent in urea slow-release fertilizer (SRF) production. This research aims to analyze the effect of urea SRF formulation (FA, FB, FC, and FD), with the combination of SAP and activated carbon, on the characteristics and nitrogen release behavior. SRF was characterized by Scanning Electron Microscope (SEM), Fourier Transform Infra-Red (FTIR), and Water Retention (WR) testing to determine the morphological structure, functional groups, and the ability of the sample to retain water during observation. The percentage of nitrogen release from SRF was calculated using the Kjeldahl method. The results of SEM characterization show that the thickness of the layer formed is about 63.5 µm. Different sample formulations affect the intensity of the functional groups produced. From all formulations, FD showed the highest WR and the lowest nitrogen release percentage with values of 80.2% and 20.4%, respectively. In general, it can be concluded that the combination of SAP from disposable diapers and activated carbon can be used as a coating agent in SRF production.
Mini Review: Analysis of The Influence of Work Environment on SMAW (Shielded Metal Arc Welding) Results Nursafitri, Gita; Indriawan, Ari Dwi Nur
Sainteknol : Jurnal Sains dan Teknologi Vol. 23 No. 1 (2025): June 2025
Publisher : Universitas Negeri Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/sainteknol.v23i1.25328

Abstract

This study aimed to systematically investigate the influence of key environmental factors on the quality of Shielded Metal Arc Welding (SMAW) outcomes. The welding process, although widely applied across various industrial sectors, remains highly sensitive to variations in its surrounding environment. Through a systematic review of previous research, academic articles, and industrial reports, this study identified temperature, air pollution, and ventilation as the most critical environmental variables. Temperature fluctuations were found to cause weld defects such as porosity and cracking. Optimal welding performance was observed within an ambient temperature range of 10°C to 30°C, with several studies suggesting narrower optimal ranges of 15°C to 28°C or 16°C to 27°C. Temperatures below 10°C accelerated weld cooling, increasing the risk of cold cracks, while those above 30°C degraded electrode coatings, leading to porosity. Moreover, airborne contaminants—including Fe₂O₃, MnO, and CO concentrations exceeding 5 mg/m³—were shown to reduce tensile strength by 15% to 20%. Adequate ventilation, particularly using mechanical systems like local exhaust ventilation (LEV), was more effective than natural ventilation in enclosed welding environments. Integrating air filtration with precise temperature control could reduce weld defects by up to 50%. The study provides practical recommendations for improving weld quality and promoting industrial safety.
Density–Porosity Interplay in Epoxy‑Based Syntactic Foams Reinforced with K15 Glass‑Silica Microballoons Hidyus, Sofi Alifia; Budiwirawan, Agung; Musyono, Ari Dwi Nur Indriawan; Setiadi, Rizky; Bunyamin, Bunyamin
Sainteknol : Jurnal Sains dan Teknologi Vol. 23 No. 2 (2025): December 2025
Publisher : Universitas Negeri Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/sainteknol.v23i2.23886

Abstract

Syntactic foam is a lightweight, high‑strength composite consisting of a polymer matrix filled with hollow microspheres (microballoons). This study examines how the volume fraction of glass‑clad silica microballoons K15 (10–50 vol %) affects the density, porosity, and void distribution of epoxy‑bonded syntactic foams. Specimens were molded in accordance with ASTM D790, conditioned for 48 h (23 ± 2 °C; 50  ±  5 % RH), and their density was measured by the pycnometric method specified in ASTM D792. Porosity was calculated theoretically and validated by SEM–EDS imaging of fracture cross‑sections. Results show a linear decrease in density from 1.15 g cm⁻³ (0 vol %) to 0.63 g cm⁻³ (50 vol %), while porosity rises exponentially from 2.7 % to 18.4 %. Morphological analysis confirms a homogeneous microballoon dispersion up to 30 vol %, but agglomeration and interbinder voids appear above 40 vol %, leading to uncontrolled porosity. A strong negative correlation (R² = 0.96) is observed between density and effective porosity. A 30 vol % K15 loading is identified as the optimum, achieving a 28 % density reduction without a significant porosity spike. These findings provide a basis for designing sandwich cores and amphibious flotation structures that require high strength‑to‑weight ratios.
Recycling End-of-Life (EoL) Reverse Osmosis (RO) Membranes into Ultrafiltration Membranes using Potassium Permanganate (KMnO4) for Aquaculture Water Filtration Putri, Raden Rara Dewi Artanti; Triwibowo, Bayu; Prasetiawan, Haniif; Salwa, Dian Fatimatus; Fauziah, Whilda; Pradana, Daffa Zamiira; Aldiansar , Divifan Armyko
Sainteknol : Jurnal Sains dan Teknologi Vol. 23 No. 2 (2025): December 2025
Publisher : Universitas Negeri Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/sainteknol.v23i2.32896

Abstract

Sustainable and economical management of aquaculture water is a significant challenge in the fisheries industry. This study aims to convert End-of-Life (EoL) Reverse Osmosis (RO) membranes into Ultrafiltration (UF) membranes using a potassium permanganate (KMnO4) solution as an oxidizing agent to enhance the efficiency of aquaculture water filtration. The conversion process involves immersing the used RO membranes in a 4,5% w/v KMnO4 solution for 3 days at room temperature. Prior to conversion, the membranes were cleaned using a 0,1% w/v Sodium Dodecyl Sulfate (SDS) solution and 0,05 M Ethylenediaminetetraacetic Acid (EDTA) to remove organic and inorganic contaminants. The results showed an increase in water flux from 20 L/m²•h to 50 L/m²•h after conversion. The analysis of aquaculture water quality after filtration using the converted UF membranes showed a significant reduction in Biological Oxygen Demand (BOD) from 5,547 mg/L to 3,817 mg/L, representing 31,2% reduction, and Chemical Oxygen Demand (COD) from 29,91 mg/L to 24,22 mg/L, representing 19% reduction. The membranes were highly effective in removing coliforms, achieving a 100% reduction from 180 MPN/100mL to 0 MPN/100mL. The values of DO and TDS decreased by only about 2%, salinity values remained unchanged, while total ammonia increased. The conversion process increases efficiency filtration, reduces operational costs, and decreases membrane waste. 

Page 2 of 2 | Total Record : 18