bluuebunny/crossref_metadata_2025_split huggingface dataset:
Changing magnetic ground state by an electric field in a single-layer FeCl2
Authors: Prayitno T B 
Published: October 2024

Abstract
Employing the electric field has been performed to investigate the magnetic ground state in a single-layer iron dichloride (FeCl2). We provided some lattice parameters to see the ground state dependency on the electric field. To minimize the computational time, we applied the generalized Bloch theorem via density functional theory to avoid the supercell approach. As we varied the electric field, we saw the magnetic transition for some lattice parameters. In addition, the magnetic moments were nearly stable for all those states, indicating the high spin state. As a concluding remark, employing the electric field is very useful to manipulate the ground state that can be applied to magnetism-based nanotechnology.
Automated waste detection system for river surveillance in Jakarta using background substraction method
Authors: Solichin A , Salman A A , Painem  
Published: October 2024

Abstract
In Jakarta, the issue of river pollution due to indiscriminate waste disposal poses serious environmental and safety concerns, often leading to flooding during the rainy season. Manual surveillance by human resources has proven ineffective in addressing the escalating scale of the problem. This study presents an automated waste detection system for river surveillance in Jakarta, especially inorganic waste, utilizing video processing techniques, specifically background subtraction and frame differencing. We collected and analyzed video data from 13 rivers, including the Ciliwung, Angke, and Pesanggrahan rivers, during October and November 2023. The system’s performance was evaluated based on its accuracy in detecting waste objects, with detection rates varying significantly across different rivers. High detection accuracies were achieved in the Cipinang (93%) and Malang (90%) rivers, while lower accuracies were noted in rivers like Grogol (25%) and Cakung (17%). The overall average detection rate was 60%. These results highlight the system’s strengths in cleaner, less dynamic environments and its challenges in more complex conditions. Future research should focus on enhancing algorithm robustness, incorporating adaptive thresholding, and integrating multi-sensor data to improve detection accuracy.
Study on Characteristics of Epoxy Resin-Based Plastic Scintillators for Detectors with Simulation Using Monte Carlo Code
Authors: Kasmudin K , Rezon K 
Published: October 2024

Abstract
To determine the presence of radioactive materials emitting gamma rays entering or exiting nuclear facilities, ports, airports, international borders, or other strategic locations, radiation portal monitors (RPMs) capable of detecting such gamma radiation need to be installed in these places. National Research and Innovation Agency of Indonesia (BRIN) is currently developing RPMs with detector components made of plastic scintillator based on epoxy resin and augmented with aromatic fluorescent materials to produce visible light, which is the working range of the photomultiplier tube (PMT) or silicon photomultiplier (SiPM). This research aims to study the characteristics of the gamma photon radiation energy spectrum from Co-60, Cs-137, and Ir-192 sources in an epoxy resin plastic scintillator and study the absorbed dose of the scintillator to gamma photon radiation energy from Co-60, Cs-137, and Ir-192 sources as a function of source distance and incidence angle of gamma rays with simulations using the MCNPX code. The scintillator is modeled in the form of a cylinder with a diameter of 5 cm and a height of 5 cm. To simulate the gamma photon radiation energy spectrum in the scintillator, the F4 tally was used and to simulate the scintillator absorbed dose, the F6 tally was used. This simulation used gamma sources of Co-60, Cs-137, and Ir-192 of 1 mCi each. These characteristics of the epoxy resin plastic scintillator have been successfully simulated. Data on the characteristics of epoxy resin plastic scintillators is important to know and study as supporting data in making plastic detectors as part of the manufacture and development of RPM.
Atomic defects (vacancy, substitutional, and Stone-Wales) in monolayer aluminum nitride: a density-functional-theory simulation
Authors: Fadlliyana M , Oktavina C W , Fajariah N , Nugraheni A D , Sholihun  
Published: October 2024

Abstract
Aluminum nitride (AlN) is a mechanically strong material with a high melting point and excellent thermal conductivity. In this study, the AlN is modeled with defects in vacancies, substitutions, and Stone-Wales using a density functional theory (DFT). We model six configurations, two configurations of monovacancies: aluminum vacancy (VAl) and vacancy nitrogen (VN), two configurations of substitutions: aluminum substitution (SN→Al) and nitrogen substitution (SAl→N), the interchange (IAl↔N), and Stone-Wales (S–W). We find structural changes in each defect with outward relaxation and VN with inward relaxation. the band structure calculations show that the geometric structure introduces new states near the Fermi level except for the VAl system.
Design of a Portable Spectrophotometer Based on Raspberry Pi for Tea Type Classification Using Machine Learning
Authors: Suhendar Haris , Silambi Michael Setiyanto , Pratama Muhammad Ridho 
Published: October 2024

Abstract
The use of spectrophotometers in food and beverage quality analysis has become common. However, portability and high cost have long been a problem for food industry players and small-scale laboratories. In this study, a more compact and low-cost spectrophotometer has been developed using raspberry pi. To validate its performance, the prototype was used to classify green tea, black tea, and oolong tea types. The research started with designing and assembling the hardware using a raspberry pi camera with Complementary Metal Oxide Semiconductor (CMOS) sensor, Digital Versatile Disk (DVD) as diffraction grating, white LED as light source and 3D printer as casing. The prototype was then used to acquire data from green tea, black tea and oolong tea solutions. In the tea type identification process, Principal Component Analysis (PCA) was applied to the data obtained. The experiment involved 30 solution samples of each of the three types of tea. The light source was directed past the sample towards the slit and DVD, then the spectrum image of the light source was displayed through a user interface built using python programming. This research resulted in a spectrophotometer with dimensions of 260 mm x 120 mm x 63 mm that is capable of capturing light spectra in the range of 400 - 700 nm. Based on the experimental results, the classification accuracy of the three types of tea using CNN and Decision Tree reached 100%.
Development Of Smart Band For Vital Signs Monitoring System Based On Internet Of Things
Authors: Umiatin U , Laut T N , Ifa R P N , Faisal M R 
Published: October 2024

Abstract
Vital signs are important health parameters because they indicate the physiological functions of the human body. Heart rate (HR), blood pressure, body temperature, oxygen saturation (SpO2), and respiration rate are vital signs used to determine whether a person is healthy or not. HR is the rate at which the heart pumps blood and is measured by the number of heart beat per minute (beats per minute / BPM). Oxygen saturation (SpO2) indicates the level of hemoglobin in the blood that can bind to oxygen. This study aims to develop a smart band prototype for monitoring heart rate (HR) and oxygen saturation using optical spectroscopy methods and the implementation of the Internet of Things (IoT). This smart band prototype uses the MAX30102 sensor, ESP32, push button, Blynk, and Arduino IDE AVR software. The research results show that the prototype’s accuracy for HR measurement is ±98.5%, and the accuracy for SpO2 is ±99.3%. The measurement results can be sent and displayed in the Blynk application as well as to email. It can be concluded that this smart band can detect HR and SpO2 in real-time and has the potential to improve the quality of healthcare services.
Analysis of Electronic and Thermoelectric Properties of Janus Materials Based on Molybdenum
Authors: Kurniawati L , Muntini MS 
Published: October 2024

Abstract
Thermoelectric devices, which directly convert heat into electrical energy, hold great potential for efficient energy transformation. With the abundant availability of heat energy, global research has increasingly focused on developing thermoelectric materials that enhance conversion efficiency. The performance of these materials is often evaluated using the Figure-of-Merit (ZT), a measure influenced by variables such as the Seebeck coefficient, electrical conductivity, and thermal conductivity. High-performing materials typically exhibit a strong Power Factor (PF) and a high ZT value. This study investigates the thermoelectric properties of Janus materials based on molybdenum, utilizing a computational approach. We employed density functional theory (DFT) to solve Schrödinger’s equations and Boltzmann transport theory through Quantum ESPRESSO and BoltzTraP2 software platforms. The results demonstrate that the studied Janus compounds possess stable structures. The electronic properties indicate direct band gaps of 1.58 eV for MoSSe (a Janus structure combining molybdenum, sulfur, and selenium), 1.04 eV for MoSTe (a combination of molybdenum, sulfur, and tellurium), and 1.3 eV for MoSeTe (a combination of molybdenum, selenium, and tellurium). Indirect band gaps were found to be 0.23 eV for MoTeO, 0.8 eV for MoSeO, and 1.12 eV for MoSO. Among the materials studied, MoSSe exhibited the highest thermoelectric properties, with a power factor of 0.003 W/mK2 for p-type and 0.0031 W/mK2 for n-type. These findings suggest that Janus MoSSe is a promising candidate for the development of 2D thermoelectric devices, potentially advancing thermoelectric technology.
Mesh-Free Solution of 2D Poisson Equation with High Frequency Charge Patterns Using Data-Free Physics Informed Neural Network
Authors: Suhendar Haris , Pratama Muhammad Ridho , Silambi Michael Setyanto 
Published: October 2024

Abstract
In this paper, we present a data-free physics-informed neural networks (PINNs) approach for solving two-dimensional (2D) Poisson equation, which is pivotal in fields such as electromagnetics, mechanical engginering, and thermodynamics. Traditional numerical method for solving this equation often require structured mesh generation such as Finite Element Method (FEM), which can be computationally expensive when dealing with high resolution Poisson Equation Solution. To address this challenge, we leverage the capabilities of PINNs capturing pattern of complex system by incorporating physical law and boundary condition as part of loss function on training model. While PINNs provide a robust framework for solving differential equations within boundary condition, they have struggle with capturing high-frequency pattern due to smooth nature of typical activation function used in neural networks. To evercome this issue, we enhance our model by incorporating Fourier Features Networks, which map inputs through a series of sinusoidal functions before feeding the input into the neural network. The result show that Fourier feature network can enhance convergence of training of PINNs model faster and obtained better result than PINNs without Fourier feature networks.
Low-Cost Electronic Nose for Robusta and Arabica Coffee Classification Using 1-D Convolutional Neural Networks
Authors: Iswanto B H , Muflih A M , Baith H M 
Published: October 2024

Abstract
The use of an electronic nose (e-nose) employing MQ-series sensors has become increasingly popular due to its cost-effectiveness. However, the impact of varying sampling durations on its performance, particularly in distinguishing between Robusta and Arabica coffee, has not been extensively studied. This research investigates how different sampling durations affect the e-nose’s classification accuracy. The study utilizes a 1D Convolutional Neural Network (1D-CNN) and a Support Vector Machine (SVM), with both models enhanced by a Savitzky-Golay filter to reduce noise and improve data quality. Feature selection techniques are applied to address data complexity and improve model performance. The experimental results indicate that the 1D-CNN model achieves optimal accuracy of up to 100% at a sampling duration of 200 seconds, while the SVM reaches approximately 92% accuracy under the same conditions. Notably, for applications requiring faster processing times, the SVM proves to be more effective, achieving 70% accuracy at a 20-second sampling interval, compared to 60% for the 1D-CNN. The study demonstrates that integrating MQ sensors in e-nose systems can yield effective classification results for coffee varieties, even with shorter sampling times. These findings have the potential to influence the development of cost-effective e-nose devices, making them more accessible to small and medium-sized industrial enterprises.
Verification on Molybdenum-99 (99Mo) Breakthrough from Non-Fission 99Mo/99mTc Generator to Produce Technetium-99m (99mTc) Medical Radionuclide
Authors: Ramadhanti N Z , Febriana S 
Published: October 2024

Abstract
The medical radionuclide 99mTc is the most widely used type of radionuclide in the field of nuclear medicine. 99mTc is the decay product of 99Mo. One of the quality control parameters of 99mTc is the 99Mo breakthrough limit. It is important to know the 99Mo breakthrough so that the quality of 99mTc produced can be optimal for diagnosis in nuclear medicine. This study aims to verify the 99Mo breakthrough activity from a non-fission 99Mo/99mTc generator whether they meet the established international limit standard. This research used a non-fission 99Mo/99mTc generator produced in multipurpose reactor G.A. Siwabessy, Indonesia. Gamma Spectrometer measurement of 99Mo and two 5 mL liquid standard sources of mix 133Ba and 152Eu used the same geometry. First standard as a calibration and efficiency identification function while the second standard is used to verify the measurement each at 3, 5, 7, 9 and 11 cm source to detector distance respectively. The 99Mo breakthrough activity (µCi) then devided to the activity of 99mTc (mCi) for the six eluted product from each days elution process of the generator. The results obtained showed that the 99Mo elution in the first elution had the highest breakthrough of 0.233 uCi 99Mo /mCi 99mTc, which exceeded the set limit of 0.15 uCi 99Mo /mCi 99mTc. While in the second, third, fourth, and fifth elution still have the 99Mo breakthrough, but these breakthrough did not exceed the limit and met one of the requirements of the 99mTc medical radionuclide parameter.
Fast Fourier Transform (FFT) Application For Short-Term Earthquake Precursor Analysis Using Geomagnetic Data (Case Study of Kupang Geomagnetic Station, East Nusa Tenggara, Indonesia)
Authors: Utami A , Febriani F , Irayani Z , Dewi C N , Ratnasari E A , Nuraeni F 
Published: October 2024

Abstract
Earthquake (EQ) precursors have been identified from ULF geomagnetic enhancements related to a moderate EQ in Kupang, East Nusa Tenggara, Indonesia. Three components of geomagnetic data (X, Y, and Z) collected during January-June 2010 were analyzed. The EQ occurred on May 7, 2010, and its epicenter was 27.78 km from the KPG Geomagnetic Station. The magnitude and depth of the EQ were 5 and 11.3 km, respectively. This study investigated the energy of ULF geomagnetic signals in the frequency range of 0.03 to 0.04 Hz using SDR based on FFT. The results showed that the geomagnetic energy increased approximately three days before the EQ. Due to the significant magnitude and relative proximity of the EQ to the observation station, it can be concluded that the closer the geomagnetic station from the EQ source, the more likely it is to detect anomalies caused by the EQ. Despite the increase in geomagnetic energy, the Dst index which measures the global activity of the geomagnetic variation in low-latitude regions does not indicate any extraordinary global geomagnetic activity. This indicates that geomagnetic anomalies are most likely related to EQ events.
Finding The Relationship between Pulsation Motion and Hα Emission Lines on γ Cas using Photometric and Spectroscopic Data
Authors: Dewi M , Aprilia  
Published: October 2024

Abstract
Pulsating stars show variability in brightness due to changes in their volume. There are two types of pulsation/oscillation: radial and non-radial. Radial oscillation keeps the symmetrical shape of the star, while non-radial oscillation does not. We study a pulsating star: γ Cas, classified as a B0.5 IVe variable star because of its pulsations and also an emission star due to the emission lines in its spectra. When a star pulsates, its atmosphere expands and contracts, potentially leading to the formation of shock waves. Observational features such as discontinuities in the radial velocity curve and emission lines support this phenomenon. In this study, we analyse the relationship between pulsation motion and the H

α
emission lines of γ Cas using photometric and spectroscopic data. Photometric data is obtained from the BRIght Target Explorer (BRITE) catalog, while spectroscopic data comes from the Be Star Spectra (BeSS) catalog. Both datasets cover the same observational dates: August 28 to October 26, 2015. Confirming the pulsation period of γ Cas at 1.21 days, we also discover an added pulsation period of 10 days from photometric data. To confirm this, we examine spectroscopic data from three specific dates: August 28, September 7, and 27, 2015. Notably, the relative flux of the H

α
emission lines continue to increase, leading us to conclude that these lines are indeed caused by the pulsation of γ Cas.
A Typical of Tsunami Generation Caused by Volcano Flank Collapse in Banda Neira, Maluku, Indonesia
Authors: Setyonegoro Wiko , Syahbana Arifan Jaya , Pranoto Hardjo , Haryadi Yudo , Prasetio Aditya Dwi , Pratama Aditya , Anggono Titi , Hanif Muhammad , Khoiridah Sayyidatul , Turyana Iyan , Ramdhan Mohamad 
Published: October 2024

Abstract
The history eruption of the Banda volcanoes was recorded in 1632, 1816, and 1988 and was preceded by significant earthquakes. In the eruption in 2017, there were 28 volcanic earthquakes, indicating a rock cracking process due to the movement of magma in the form of gas, liquid, and rock solids. We suspect that when the earthquake occurs, the rock-cracking process upon the eruption will potentially trigger the volcano flank to collapse into the sea and generate a tsunami in the Banda Naira and surrounding area. We contribute to modeling the travel time and tsunami inundation resulting from the flank collapse of Banda Volcano. BATNAS bathymetry data is used to run tsunami simulations. We use aerial photography from field survey data to interpret Banda Volcano failure parameters, including diameter, direction of sliding of the collapse, and slope of the collapse of the side of the Banda Volcano. Based on the tsunami simulation, the volcano flank collapse source on Banda Volcano produced a maximum tsunami in Banda Naira as high as 6.2 meters, and the tsunami will arrive around 6 – 8 minutes. While in AI Island, tsunami inundation reached 55.87 m and arrived in 4 minutes. Meanwhile, the maximum elevation of Banda Naira Island is 3.5 meters, with a population of 21,000 people in March 2024. Tsunami inundation has the potential to submerge entire residential areas in Banda Neira.
BIMA 2.0 Progress on ToM Analysis of Contact Binaries: IR Car, V1370 Tau and GY Pup
Authors: Budi B. D. S. , Araska S. F. , Akbar E. I. , Yap F. , Muazarah S. N. , Malasan H. L. , Irawati P. 
Published: October 2024

Abstract
The Eclipsing Binaries Minima (BIMA) 2.0 Monitoring Project is a continuation of the previous BIMA program that was initiated by the collaboration of Bosscha Observatory - Lembang, Indonesia and The National Astronomical Research Institute of Thailand (NARIT) in 2012. This project aims to build an open database of eclipsing binary minima and establish each system’s orbital period and its variations in a time of minima (ToM) photometric observation using the Thai Robotic Telescope (TRT) network. In this work, we will present the progress of our monitoring program during

3

∼

months of observations using TRT with proposal ID TRTC11A_009. We have collected ToM data at least once on 18 samples of contact binary stars and carried out O-C diagram analysis on three selected objects: IR Car, V1370 Tau, and GY Pup. We obtained six, three, and four primary minima on IR Car, V1370 Tau, and GY Pup, respectively. These three objects were chosen due to the lack of ToM data in recent years. We also use the TESS space mission ToM data to increase data coverage. Preliminary results show a significant change in O-C values and indicate mass transfer in this system.
Morphology of NGC 6886 Using IFU Data
Authors: Akbar E I , Fitriyani N , Soemitro A A , Malasan H L , Puspitarini L , Haryana N S , Muazarah S N , Yap F , Araska S F 
Published: October 2024

Abstract
In this paper, we report the first investigation of NGC 6886 utilizing IFU data, allowing us to build a more comprehensive morphological study based on many emission lines. NGC 6886 is a young planetary nebula featuring emission lines with varying levels of excitation. Using data from Potsdam Multi-Aperture Spectrophotometer (PMAS), we construct an integrated spectra and identify 27 emission lines. We calculate the flux ratio of each line relative to Hβ. Lines stronger than Hβ are [OIII] 5007, [OIII] 4959, [NII] 6584, Hα 6563, [NII] 6548, and [NeIII] 3869. We also construct 16 emission line maps to examine the morphology and ionization structure of NGC 6886 and we show that there are two geometrical structures within the nebula.
Spectral Transformation Detection in Be Stars Using Multi-Parameters Analysis of Delta Scorpii, Eta Centauri, and Kappa Lupi
Authors: Wicaksono A R , Aprilia  , Budi B D S , La Fatsa F , Sutanto R A 
Published: October 2024

Abstract
Over the past five years, the Bosscha Observatory in Bandung, Indonesia, has dedicated significant attention to studying B-emission (Be) stars exhibiting distinctive emission characteristics. In this work, we meticulously analyzed the spectra originating from three prominent Be stars: Delta Scorpii, Eta Centauri, and Kappa Lupi. We also took additional spectrum data from the BeSS repository for each of the three stars to maximize our analysis results. Our analysis revolved around quantifying crucial spectral attributes, including the emission peak centers, the equivalent width (EW), and the full width at half maximum (FWHM). These parameters proved pivotal for deriving the violet-to-red peak intensity ratio (V/R), emission-to-continuum ratio (E/C), and the star’s radial velocity. Based on our analysis, there are several things to be pointed out. For all stars, there was no such significant variation in E/C values. Our single-peak analysis of δ Sco showed a strong emission primarily caused by the presence of a circumstellar disk of gas. FWHM of Hα in κ Lup demonstrated minor variability with time, meanwhile FWHM of Hα in η Cen decreased with time and orbital phase. Much more intense observations and analysis should provide better data to conclude the variability pattern of those parameters.