Journal of Energy, Material, and Instrumentation Technology

Design and Development of a Measuring Instrument for Cholesterol Level Detection in The Blood Using Non-Invasive Techniques Based on the Wemos D1 R1 Microcontroller

2025-03-11T15:51:05+00:00

Cholesterol level checks are generally performed either invasively or using a portable blood test strip. It requires a long laboratory analysis time and causes pain in the body, so a non-invasive tool is needed to check cholesterol levels. The study aims to detect cholesterol levels in the blood with a non-invasive technique based on the Wemos D1 R1 Microcontroller using the DS100A Oximeter Sensor. This tool is equipped with a Liquid Crystal Display (LCD) as a cholesterol level display and an LED light as a cholesterol level indicator that will light up red when cholesterol is high (>=240 mg/dL), light up yellow when cholesterol is at the high limit (200-239 mg/dL), and light up green when cholesterol is normal (<=200 mg/dL). Cholesterol level measurement is done by utilizing the red LED light emission on the sensor attached to the finger. Then, the photodiode will capture the light intensity from the red LED into a voltage value. A 10-bit ADC on the microcontroller then reads the voltage value. The ADC value was then converted into a cholesterol level in milligrams per deciliter (mg/dL) using a linear regression equation. The designed device is capable of detecting cholesterol levels in the range of 150-240 mg/dL. Test results indicate that the non-invasive cholesterol level test device has been successfully developed, with a precision of 98.85% and an error of 1.15%. Accuracy testing yielded a value of 97.14% with an error of 2.86%.

The Effect of NaOH on the Synthesis of Nano ZnO Using Red Betel Leaves (Piper crocatum) by Green Synthesis Method

2024-01-22T03:56:58+00:00

ZnO has been produced using a green synthesis method. This research aims to determine the effect of NaOH variations on ZnO nanoparticles obtained using red betel leaf extract. The variation of NaOH used is 0,2; 0,4; 0,6; the characterization carried out was Fourier Transformation Infra Red (FTIR), X-Ray Difraction (XRD), Scanning Electron Microscopy (SEM), dan Ultra Violet Vissible (UV DRS) the results of FTIR characterization show that the functional groups in red betel leaves play a role in the information of ZnO nanoparticles, XRD characrerization shows diffraction peaks of ZnO nanoparticles and the presence of NaNO₃ phase at 0,2; 0,4; 0,6; and 1 M variation. Then, the SEM results showed a spherical morphology at a 1 M variation, and the UV-DRS results showed an absorption peak at 331 nm and a band gap energy of 3.11 eV.

Analysis of Aluminium Alloy 6061 Material Coating with the Addition of Malonic Acid Additive in the Plasma Electrolytic Oxidation Method to Improve Corrosion Resistance Properties

2025-07-14T16:14:50+00:00

Aluminum alloy 6061 is extensively used in structural and engineering applications due to its favorable strength-to-weight ratio, good mechanical properties, and inherent corrosion resistance. However, it remains vulnerable to localized corrosion, especially in chloride-rich environments. This study investigates the effect of malonic acid (MA) as an organic additive in the Plasma Electrolytic Oxidation (PEO) process to enhance the corrosion resistance of aluminum alloy 6061. The experimental results indicate that the presence of MA reduces plasma initiation time, stabilizes discharge behavior, and facilitates the formation of a denser and more uniform oxide layer. Surface morphology analysis reveals that PEO coatings with MA exhibit finer porosity and a thicker structure, contributing to improved barrier properties. XRD characterization confirms the presence of stable crystalline phases such as mullite and andalusite in the MA-enhanced coatings. Electrochemical testing via Tafel polarization shows a significant reduction in corrosion current density (3.899 x 10^-7 A/cm²) and corrosion rate (0.642 mm/year), alongside a more positive corrosion potential (-2.616 V) in the MA-treated samples. When compared to traditional corrosion inhibitors, both organic (for example, imidazole-based compounds) and inorganic (for example, CaCO₃ and SiO₂), the PEO plus MA method demonstrates superior long-term corrosion resistance and structural stability. These findings highlight the potential of malonic acid as an effective additive for optimizing the PEO process in demanding environmental conditions.

Effect of Layer Deposition and Thermal Treatment on the Structural, Optical, and Electrical Characteristics of Spin-Coated CaTiO3 Thin Films

2025-08-19T02:06:11+00:00

This study investigates the effect of coating repetition and annealing temperature on the structural, optical, and electrical characteristics of calcium titanate (CaTiO₃) thin films synthesized via a sol-gel spin coating method. The number of coatings (2, 4, 6, and 8 layers) and annealing temperatures (250 C, 350 C, and 450 C) were varied to optimize the characteristics. X-ray diffraction analysis indicated an improvement in crystallinity with increasing annealing temperature, as evident from the growing diffraction peaks. UV-Vis spectroscopy revealed a decrease in the optical band gap from 3.741 eV to 3.554 eV with increasing coating layers and thermal treatment, suggesting enhanced optical absorption. Current-voltage measurements using a two-point probe method generally showed linear conduction, indicative of ohmic behavior, with one sample exhibiting a mild nonlinear response at higher bias. The results confirm that process parameters significantly influence the functional properties of CaTiO₃ thin films. This fundamental study provides a foundation for employing CaTiO₃ as a functional layer in perovskite-based photovoltaic devices, paving the way for further device integration and optimization.

Development of a Portable Low-Cost Multispectral Sensor Integrated with IoT and Machine Learning for Classifying Honey Types

2025-07-20T11:48:30+00:00

Accurate honey type authentication is a significant challenge for small-scale producers, as conventional methods are often costly and impractical. This study aims to design and develop a low-cost honey classification prototype by integrating the AS7265X multispectral sensor with Internet of Things (IoT) technology and machine learning. Spectral data from 18 channels of various Indonesian honey types were acquired using the AS7265X sensor and analyzed exploratively using Principal Component Analysis (PCA) and Linear Discriminant Analysis (LDA). The data were then normalized and used to train Artificial Neural Network (ANN), Random Forest (RF), and Support Vector Machine (SVM) classification models. An ESP32-based IoT system was developed for real-time monitoring and cloud data storage. The results demonstrate that AS7265X spectral data effectively differentiate honey types, with the ANN model achieving 94.05% accuracy, supported by a responsive IoT system (1–2 seconds) for monitoring and centralized storage. This prototype shows potential as a practical, rapid, accurate, and efficient honey authentication solution for various stakeholders.

Sustainable Lithium Battery Development in Indonesia: The Role of Natural Materials and Recycling Processes in Future Challenges

2025-07-20T11:55:50+00:00

The development of sustainable lithium-ion batteries is essential to meet the global demand for efficient, high-capacity, and environmentally friendly energy storage systems. This study reviews recent advancements in lithium battery technologies in Indonesia, emphasizing the utilization and performance of locally available natural materials. Among various lithium-ion battery types, those based on Lithium Nickel Manganese Cobalt Oxide (NMC) and Lithium Iron Phosphate (LFP) are considered the most promising for Indonesia due to the availability of key raw materials such as nickel, cobalt, and iron. Additionally, various battery recycling techniques—including pyrometallurgy, hydrometallurgy, bio-hydrometallurgy, and direct recycling methods—are systematically analyzed for their effectiveness in material recovery and environmental impact mitigation. The findings highlight the need for integrated strategies that combine local material utilization, innovation in battery materials and recycling technologies, environmental stewardship, and supportive regulatory frameworks to accelerate the development of a sustainable lithium-ion battery ecosystem in Indonesia.

Enhancing BLDC Motor Performance with Wheel-Hub Design by Modify Coil Configurations

2025-08-06T02:57:49+00:00

This paper presents an analysis of the design method of a BLDC (Brushless DC) motor with a wheel-hub structure. This study examines how variations in winding configuration affect motor performance. A 650W wheel-hub BLDC motor will be tested by modifying its stator design, including variations in the number of wires, the number of parallel circuits, and the diameter of its conductor. The test focuses on the effect of these changes on the torque, efficiency, output power and rotational speed of the motor.The test was carried out using standard sized wires. The results show that appropriate winding arrangements can increase motor torque and speed. When the parallel circuit configuration is used, the motor efficiency increases and the wire diameter is optimized. Based on the design implementation carried out, the 650W hub-type BLDC motor tested was able to achieve a maximum power of 956W, a maximum speed of 477 rpm, and a maximum torque of 41 Nm. In addition, the highest efficiency achieved was 86% at a torque of 31.8 Nm, a speed of 239 rpm, and a power of 956W.The results of this study emphasize the importance of proper winding configuration in optimizing motor performance. This winding configuration selection procedure is expected to be a reference in the manufacture of wheel-hub BLDC motors.