Science, Technology, and Communication Journal

Implementation of fuzzy analytical hierarchy process (FAHP) and TOPSIS for scholarship decision support system for the underprivable

Fitra Kurnia — 2026-02-10

Scholarship is part of assistance given by organization, company, institution or person. One of the existing scholarships at SMKN 2 Bengkalis is underprivileged scholarship given to students with middle to lower economic levels. This research does for helping underprivileged scholarship selectors in SMKN 2 Bengkalis to choose who are recommended eligible students as recipients of underprivileged scholarships with set established criteria before. Fuzzy analytical hierarchy process method implemented in this research with 7. With several criteria having each 4 – 5 values. And this research uses 239 active students data in SMKN 2 Bengkalis in 2021 as a decision alternative. Testing is done with 2 methods that are black box which system has worked in accordance with expected and UAT by 79% of both respondents. After obtaining the preference value, the final results of the ranking are obtained, the order of the smallest value of the student who is most. Entitled to receive scholarship assistance, namely students 1, 5, and 10.

Ultra-wideband diamond-shaped metamaterial absorber for radar cross section reduction

Defrianto Defrianto — 2026-02-23

This study presents the design and full-wave simulation of a diamond-shaped metamaterial absorber configured in a 4×4 array for applications in radar cross section reduction (RCSR). The structure was modeled on an FR-4 substrate with a copper patch and metallic ground plane to achieve high absorption across the ultra-wideband (UWB) frequency range of 0.09 – 10 GHz. Simulations were conducted using CST Studio Suite. Key radar-related performance parameters including reflection (S11), transmission (S21), and absorption were analyzed. Results indicate that the absorber achieves extremely low reflection values (return loss up to -85 dB), near-zero transmission due to the ground plane, and absorption exceeding 80% in targeted radar bands. These findings demonstrate the high potential of diamond-shaped metamaterial absorbers for stealth applications and electromagnetic wave attenuation in modern radar systems.

Optimization of heart rate measurement using fast Fourier transform modeling on electrocardiogram signals

Siti Fatimah — 2026-02-25

Heart rate measurement based on electrocardiogram (ECG) signals is commonly performed through traditional observation techniques, which can be less effective especially when restricted to short-range. Such limitations may hinder the detection of subtle variations in cardiac rhythm, potentially resulting in the omission of critical time-dependent physiological information. To overcome this challenge, a computational approach is introduced to enhance both the accuracy and consistency of heart rate estimation. The fast Fourier transform (FFT) is applied to convert ECG signals from the time domain to the frequency domain, allowing for accurate identification of dominant spectral components associated with cardiac activity. This transformation also enables the evaluation of long-range, which is often impractical to analyze using time-domain methods alone. A dataset consisting of ten ECG signal recordings from subjects with normal heart function was utilized. Waveform images were digitized using PlotDigitizer software and further processed in MATLAB through spectral transformation. The resulting frequency components were accurately identified, with a mean absolute error of less than 0.2% when compared to reference values. These results demonstrate the effectiveness of a frequency-based analytical approach in improving measurement precision and promoting efficiency in digital cardiac monitoring. The findings contribute to the development of advanced biomedical signal processing techniques.

Analysis of single-mode optical fiber splicing loss in telecommunications network systems

Widia Damayanti — 2026-02-26

This paper investigates the impact of angular misalignment on splice loss across five distinct types of single-mode fiber (SMF), a critical factor in optical fiber network reliability. We regularly analyze splice loss at misalignment angles ranging from 0.1° to 1°, evaluating performance at both 1310 nm and 1550 nm wavelengths. Our findings consistently show that increasing angular misalignment directly causes a significant increase in coupling loss, with the SMF-28e+ showing the lowest susceptibility, recording losses of 0.7299 dB at 1310 nm and 0.672 dB at 1550 nm for a 1° angle. These detailed insights into the angular misalignment tolerance of various SMF types is crucial for enhancing the design and deployment of robust and efficient optical fiber networks, ultimately minimizing signal degradation and improving overall network performance.

Recombination coefficient analysis of hydrogen plasma species in the afterglow regime

Felix Boy Martupa Sihombing — 2026-02-26

The recombination coefficient of hydrogen plasma using the six thermal hydrogen species in the afterglow condition was analyzed through MATLAB computational modeling to determine the logarithmic density, and then to determine the difference between conduction and convection. This study aims to model the dynamics of recombination and determine the recombination coefficients of hydrogen species against temperature variations. This modeling was carried out using zero-dimensional chemical kinetic equations derived from the continuity equation, namely the reaction rate calculated using modified Arrhenius. This modeling is integrated numerically using the Runge-Kutta method. The density results of hydrogen species show a consistent decrease in temperature variation related to the ideal gas law, but the recombination coefficient increases with increasing temperature. This upward trend indicates that there is a dominance of three-body recombination processes over atmospheric pressure and afterglow conditions.

Performance of optical fibers birefringence and its effect on wavelength

Nadia Rahayu — 2026-02-28

The phenomenon of refractive index difference between two orthogonal polarization modes in optical fibers, plays as an important role in optics transmission systems and precision sensors. This study aims to analyze the effect of wavelength on the birefringence performance of five types of single-mode optical fibers, namely SMF-28, SMF-28e, SMF-28e+, SMF-28e+LL, and SMF-28 ULL. Simulations were performed using OptiFiber software with wavelengths varying from 1000 nm to 1550 nm. The results show that the birefringence value decreases significantly as the wavelength increases, in line with the propagation of the optical field into the sleeve which reduces the refractive index difference between the two orthogonal modes. The highest birefringence value was recorded for SMF-28e+ at 9.28 rad/m 1000 nm, while the lowest value was 5.79 rad/m 1550 nm. In addition, external effects such as fiber curvature showed a contribution to the change in birefringence, which is relevant for the design of precision optical systems. These findings confirm the importance of controlling wavelength parameters and geometric structure in optimizing fiber birefringence performance for polarization- based optical communication and sensor applications. Suggestions for further research is to evaluate the effect of temperature, external pressure, and voltage on birefringence in various other types of optics fibers.

Design and characterization of a graphene-coated fiber Bragg grating gas sensor for low-concentration methane and carbon dioxide detection

Dedi Irawan — 2026-02-28

Early detection and accurate monitoring of methane (CH₄) and carbon dioxide (CO₂) at low concentrations are essential for industrial safety, environmental monitoring, and greenhouse gas mitigation. Conventional gas sensors, including electrochemical and semiconductor types, suffer from environmental sensitivity, frequent calibration needs, and limited long-term stability. Therefore, more stable, sensitive, and intrinsically safe sensing technologies are required, especially for high-risk environments. Fiber Bragg grating (FBG) sensors offer key advantages as passive optical devices that are immune to electromagnetic interference, compact, and capable of multiplexed operation. This study presents the design and characterization of a graphene-coated FBG sensor for low-concentration CH₄ and CO₂ detection. The FBG was fabricated using the phase mask technique, followed by cladding etching to enhance evanescent field interaction with the surrounding medium. A graphene layer was synthesized via chemical vapor deposition (CVD) and transferred onto the etched fiber surface to serve as the active sensing layer. Gas adsorption on graphene induces refractive index variations, producing measurable Bragg wavelength shifts monitored by a high-resolution optical interrogator. Experiments were conducted at concentrations up to 100 ppm under controlled temperature and humidity conditions. Results show sensitivities of 12.4 pm/100 ppm for CO₂ and 9.7 pm/100 ppm for CH₄, with strong linearity (R² > 0.98), fast response time (< 15 s), low hysteresis, and good long-term stability. The proposed FBG-graphene sensor demonstrates strong potential for reliable real-time gas monitoring in industrial and environmental applications.

IoT-based smart irrigation protocol for water efficiency and soil moisture stabilization in lowland horticulture

Adeela Nurul Hadi — 2026-02-28

Conventional irrigation in horticultural land continues to face challenges related to water wastage and soil moisture instability, particularly in Indonesia's lowland regions. This study proposes a smart irrigation system based on the internet of things (IoT) with a closed-loop control mechanism to enhance water use efficiency and maintain optimal soil moisture. The system was designed using NodeMCU ESP8266, soil moisture sensor, DHT11 sensor, 12V water pump, and Blynk platform for remote monitoring. Sensor calibration was performed using gravimetric method and linear regression, yielding a conversion equation of Y = 78.00 - 0.8391X with a correlation coefficient of r = -0.965. Experimental testing over three days was conducted on bird's eye chili, corn, and water spinach plants, comparing the IoT system against manual irrigation. Results demonstrated that the system maintained average soil moisture of 55.23% compared to 43.53% in conventional methods, saved up to 25.9% water, and increased Water Use Efficiency by 62.7%. These findings indicate that the IoT irrigation system is effective, economical, and has potential to support sustainable precision agriculture.

Enhanced social media phishing detection model using LSTM and BERT

Wenni Syafitri — 2026-02-28

Phishing attacks are a major cyber threat, with more than 30% of incidents occurring via social media platforms, especially short message services. This study evaluates deep learning approaches for automated phishing detection using BERT and Hybrid (BERT-LSTM) architectures fine-tuned on 15950 annotated SMS. The BERT-only model achieved superior performance (F1 0.9928, recall 0.9952, AUC 0.999) with no statistically significant improvement from adding BiLSTM layers (0.0006). K-fold cross-validation demonstrated robust generalisation (coefficient of variation 0.10%). Dataset saturation analysis indicated that 15,950 SMS are sufficient for effective transfer learning. Mild overfitting (6.3x loss ratio) remained within acceptable bounds and did not affect validation metrics. The 1.77% false positive rate and 99.52% recall enable practical deployment for production phishing defence. Results demonstrate that transfer learning with BERT achieves production-grade performance while challenging conventional assumptions about architectural complexity.

Communicating customer value in sustainable fashion: Strategies and implications review for ethical consumerism

Ikhma Zurani — 2026-02-28

The fast fashion industry, with its penchant for consumerism, trash, and greenhouse gas emissions, is primarily responsible for environmental damage. Slow fashion is a movement that aims to promote more responsible consumerism through its emphasis on sustainable practices, ethical manufacture, and long-lasting design. In order to express sustainable ideals to consumers in the fashion industry, this study examines successful sustainability communication tactics. As a result of being impacted by honesty, equity, and repurposed goods, slow fashion customers place a premium on ethical business methods, environmental consciousness, and classic style. Constructal level theory, meanwhile, shows that while abstract messages reach more people, sustainability-conscious consumers are more receptive to concrete ones. However, despite the continued ineffectiveness of organisational green marketing, attitudes towards green products among Generation Z are driving sustainable behaviour. The environmental problems caused by rapid fashion necessitate more stringent regulations and consumer education, particularly in Vietnam. The findings of this study can help fashion industry stakeholders and policymakers tackle sustainability issues.