cover
Article Per Year (5 Year)
All
Home Page
OAI Link
Editorial Team
Contact
Reviewer
Google Scholar
Contact Name
-
Contact Email
-
Phone
-
Journal Mail Official
-
Editorial Address
-
Location
Kab. ogan ilir,
Sumatera selatan
INDONESIA
Science and Technology Indonesia
Published by Universitas Sriwijaya
ISSN : 25804405     EISSN : 25804391     DOI : -
Core Subject : Science, Social, Engineering,
Biochemistry, Genetics & Molecular Biology Chemical Engineering, Chemistry & Bioengineering Environmental Science Materials Science & Nanotechnology Physics
An international Peer-review journal in the field of science and technology published by The Indonesian Science and Technology Society. Science and Technology Indonesia is a member of Crossref with DOI prefix number: 10.26554/sti. Science and Technology Indonesia publishes quarterly (January, April, July, October). Science and Technology Indonesia is an international scholarly journal on the field of science and technology aimed to publish a high-quality scientific paper including original research papers, reviews, short communication, and technical notes. This journal welcomes the submission of articles that covers a typical subject of natural science and technology such as: > Chemistry > Biology > Physics > Marine Science > Pharmacy > Chemical Engineering > Environmental Science and Engineering > Computational Engineering > Biotechnology Journal Commencement: October 2016
Arjuna Subject : -
Articles 551 Documents
 45   46   47   48   49 
Phytochemical Profile, Antioxidant Activity and Anticancer Activity of Gamma-Irradiated Black Rice Bran (Oryza sativa L.) Ethanolic Extract: In-Vitro and In-Silico Study Rukmana, Rizal Maarif; Silfarohana, Rantika; Putra, Aditya Dwi Permana; Devi Safrina; Dian Susanti; Nur Rahmawati Wijaya; M Bakti Samsu Adi; Muhammad Evy Prastiyanto; Yanuar Ashari Cahyaningrum; Rina Nurmaulawati; Weka Sidha Bhagawan
Science and Technology Indonesia Vol. 10 No. 2 (2025): April
Publisher : Research Center of Inorganic Materials and Coordination Complexes, FMIPA Universitas Sriwijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.26554/sti.2025.10.2.628-643

Abstract

Black rice is a food crop with black pigments, which helps reduce the risk of various diseases and improve health. One way to improve food quality and avoid food contaminants is by irradiating. This study evaluated the phytochemical profile, antioxidant activity, and anticancer activity of irradiated black rice bran extract (IBRBE) in vitro and in silico. Black rice was irradiated with a Gamma cell 220 type irradiator at a 7.5 kGy/hour dose rate. Extraction of irradiated black rice bran was carried out using the maceration method. Phenolic and flavonoid components were quantified using the Folin–Ciocalteau and AlCl3 methods, respectively. Phytochemical compounds were identified by liquid chromatography-high-resolution mass spectrometry (LC HRMS). The antioxidant activity of IBRBE was carried out against 2,2-diphenyl-1picrylhydazyl (DPPH). The cytotoxic activity of IBRBE against WiDr cells (colorectal cancer) and Vero (nonhuman cell lines) used the MT test method. Prediction of the inhibitory mechanism of compounds in the extract against target proteins EGFR and GPX7 was carried out in silico. Total phenolics and flavonoids were 2.57 ± 0.28 mg GAE/g and 19.12 ± 0.18 μg QE/ml, respectively. Twenty-four types of active compounds were obtained in IBRBE. The results of antioxidant activity obtained an IC50 value of 1198.45 ± 92.86 μg/ml. IC50 in WiDr cells and Vero cells were obtained at 36.08 ± 11.71 μg/ml and 570.58 ± 130.25 μg/ml, respectively. In silico results, the compound 4 Dodecylbenzene sulfonic acid has the highest binding affinity to the EGFR protein, with a value of -5.9. Meanwhile, the Monoolein compound has the highest binding affinity to the GPX7 protein, with a value of -5.4.
Transmission-Based Energies of Prime Coprime Graph for Integers Modulo Group Romdhini, Mamika Ujianita; Abdurahim; Maharani, Andika Ellena Saufika Hakim; Kamali, Siti Raudhatul
Science and Technology Indonesia Vol. 10 No. 3 (2025): July
Publisher : Research Center of Inorganic Materials and Coordination Complexes, FMIPA Universitas Sriwijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.26554/sti.2025.10.3.759-765

Abstract

Graphs are an excellent instrument that provides an algebraic structure for visualizing and interpreting molecule structures and characteristics. As a result, the problem statement arises regarding how we can interpret graphs with eigenvalues concerning their corresponding matrices. Such questions can be answered by studying spectral graph theory. This research focuses on graphs whose vertex sets are group elements in which the structure of ℤn groups and the definition of a prime coprime graph serve as the foundation for the graph building used in this study. The matrix construction of the graph is based on transmission-based matrices including Weiner-Hosoya and distance signless Laplacian matrices. Research methods include investigating the transmission properties and formulation of the characteristic equation using block matrices. The results obtained are a comprehensive analysis of eigenvalues, spectrum, and spectral radius leading to the prime coprime graph energy for ℤn groups corresponding to both matrices.
Commuting and Centralizing Maps on Modules Fitriani, Fitriani; Wijayanti, Indah Emilia; Faisol, Ahmad; Ali, Shakir
Science and Technology Indonesia Vol. 10 No. 3 (2025): July
Publisher : Research Center of Inorganic Materials and Coordination Complexes, FMIPA Universitas Sriwijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.26554/sti.2025.10.3.690-697

Abstract

A ring is a mathematical structure composed of a set with two binary operations that follow certain axioms. One important function within a ring is the centralizing and commuting mapping, which has been extensively studied in recent decades. Commuting mappings are a special case of centralizing mappings. A module is a generalization of a ring. In this paper, we extend the concept of commuting mappings from ring to module structures. However, defining commuting mappings in modules presents a challenge, as multiplication is required for their definition, yet modules do not have this operation. Additionally, constructing nonzero centralizing and commuting mappings on modules is a nontrivial task. To address these challenges, we employ the concept of idealization as a framework for defining commuting mappings in modules. We also propose a method for constructing nonzero commuting mappings on modules by leveraging existing commuting mappings in rings. Specifically, if α is a commuting mapping on a ring T, then a corresponding commuting mapping α’ can be defined on the module by utilizing α. Moreover, we establish that the finite sum of commuting mappings is also a commuting mapping and that a linear combination of  commuting mappings is also a commuting mapping under certain conditions.
The Locating Chromatic Number of the Cyclic Chain Graph Abel, Latifa Azhar; Welyyanti, Des; Yulianti, Lyra; Permana, Dony
Science and Technology Indonesia Vol. 10 No. 3 (2025): July
Publisher : Research Center of Inorganic Materials and Coordination Complexes, FMIPA Universitas Sriwijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.26554/sti.2025.10.3.958-962

Abstract

The locating chromatic number of graph G (χL(G)) combines the idea of the partition dimension and the chromatic number by considering the locations of the vertices of graph G. Let (Cni, m) be a cyclic chain graph, namely a group of blocks in the form of a cycle graph Cn1(1), Cn2(2), ···, Cni(i). The ni is the number of vertices on the i-th cycle, and m is the number of cycles, for ni ≥ 3, 1 ≤ i ≤ m, and m ≥ 2, and the vertex vi,⌈ni/2⌉+1 in Cni(i) is identified with the vertex vi,⌈ni/2⌉+1 in Cni+1(i+1). In this research, we determine χL(Cni, m) for ni ≥ 3, 1 ≤ i ≤ m, and m ≥ 2.
Carbon Price Prediction by Incorporating Fossil Fuel Prices Using Long Short-Term Memory with Temporal Pattern Attention (TPA-LSTM) Mujiono, Edo Priyo Utomo Putro; Mukhlash, Imam; Pradana, Yan Aditya; Putri, Endah R.M.; Irawan, Mohammad Isa
Science and Technology Indonesia Vol. 10 No. 3 (2025): July
Publisher : Research Center of Inorganic Materials and Coordination Complexes, FMIPA Universitas Sriwijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.26554/sti.2025.10.3.856-865

Abstract

Reliable carbon price prediction can help to stabilize the carbon market, minimize financial risks for investors, and encourage innovation in green industries. The forecasts have a crucial role in reaching advanced goals for reducing emissions, aiding the shift toward an economy with reduced carbon emissions, and lessening the adverse effects of climate change overall. This paper proposes applications of LSTM with Temporal Pattern Attention (TPA-LSTM) to predict carbon price fluctuations. The prediction of carbon price fluctuations not only draws on its own historical information but also from its main predictors, including fossil fuel prices from 2018 to 2023. The TPA-LSTM method is a combined method that uses the LSTM layer as the initial input of the model. Furthermore, the output generated by the LSTM layer serves as the input to the TPA layer, which is then used to predict the carbon price for the following day. The model is tested by predicting the test data and calculating the evaluation results. The experimental results indicate that TPA-LSTM has surpassed other models in accuracy by showing better performance based on MSE, RMSE, MAE, and MAPE metrics.
Influence of Mg Incorporation on the Structural and Electrochemical Properties of LiMn1-xMgxO2 Cathode Material for Lithium-Ion Batteries Hassan, Nour Abd Alrazaq; Al-Timimi, Muhammad Hameed
Science and Technology Indonesia Vol. 10 No. 3 (2025): July
Publisher : Research Center of Inorganic Materials and Coordination Complexes, FMIPA Universitas Sriwijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.26554/sti.2025.10.3.826-836

Abstract

 In this study, the urea route technique was used to synthesize LiMn1-xMgxO2 compounds with (x = 0, 0.125, 0.25, 0.375, 0.5, 0.625, and 0.75 wt.%) as cathode active materials for lithium-ion batteries. All prepared samples underwent structural and morphological analysis. The X-ray diffraction (XRD) results showed a single-phase crystal structure for the synthesized nanoparticles. The crystalline size (D111) of the produced particles was calculated using Debye-Scherrer’s equation, and the results indicated only a slight change in particle size upon substitution of magnesium ions. Fourier transform infrared spectroscopy (FTIR) analysis revealed several vibrational modes, including (O-H and C=O). Field emission scanning electron microscopy (FESEM) images also revealed that the nanoparticles were cubic, with little variation in size distribution. The synthesized LiMn1-xMgxO2 was further characterized by energy dispersive X-ray (EDX) spectroscopy. The findings confirmed the presence of magnesium (Mg), manganese (Mn), and oxygen (O). Electrochemical testing was conducted only on samples of LiMn1-xMgxO2 (x = 0, 0.125, and 0.75 wt.%). Electrochemical experiments showed that LiMn1-xMgxO2 (x = 0.125 and 0.75 wt.%) exhibited greater charge and discharge capacities than the LiMnO2 electrode. These results were consistent with the findings from electrochemical impedance spectroscopy (EIS). Overall, the electrochemical experiments demonstrated that LiMn1-xMgxO2 (x = 0.125 and 0.75 wt.%) performed better than LiMnO2.
An Improved Fifth-Order Runge-Kutta Method with Higher Accuracy and Efficiency for Solving Initial Value Problems Habibah, Ummu; Medrano, Fermin Franco; Permana, Adith Chandra; Ardiana, Dita; Trisilowati
Science and Technology Indonesia Vol. 10 No. 3 (2025): July
Publisher : Research Center of Inorganic Materials and Coordination Complexes, FMIPA Universitas Sriwijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.26554/sti.2025.10.3.802-816

Abstract

Solving initial value problems (IVPs) in ordinary differential equations (ODEs) often requires numerical methods, with the fifth-order Runge-Kutta method being a widely used approach due to its balance between accuracy and computational efficiency. A novel and straight forward formula for the fifth order Runge-Kutta method is proposed, aiming to simplify calculations while maintaining high accuracy and stability. The method is derived using an optimized Taylor series expansion, leading to a more efficient formulation. Numerical experiments are conducted to compare the proposed method with existing fifth-order Runge-Kutta methods. The results showthat the proposed formula out performs existing methods in terms of accuracy, stability, and computational efficiency. This new formula provides a practical alternative for solving IVPs in ODEs with improved performance.
Improved Dynamic Spectrum and Traffic Management Model Based on Demand Response and Heterogeneous Incentives with Perfect Substitute Utility Function Puspita, Fitri Maya; Octarina, Sisca; Yunita; Ramadhany, Adinda Putri; Yuliza, Evi
Science and Technology Indonesia Vol. 10 No. 3 (2025): July
Publisher : Research Center of Inorganic Materials and Coordination Complexes, FMIPA Universitas Sriwijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.26554/sti.2025.10.3.766-776

Abstract

The purpose of this research is to design and optimize a demand response based-selfish user Cloud Radio Access Network (C-RAN) model to demonstrate with a narrow-minded client utilizing three financing plans specifically level charge, usage-based, and two-part tariff. The Traffic data is classified into incoming data and outgoing data, obtained from a local server in Palembang. The optimal solution is obtained by determining the decision variables and parameters used in each case for all models, compiling improved C-RAN models as many as 2 models, namely model I, and model II, and then determining the optimal solution and sensitivity analysis using LINGO 13.0 software. The most optimal solution is obtained from model II with a flat-fee scheme in case 1 of IDR 3299.7/kbps with 45 iterations. The results of the sensitivity analysis is on the variables ak,m that allows the increase and decrease in the objective function coefficient. At the same time, the value 0 will be constant.
Synthesis and Characterization of Polyvinyl Alcohol (PVA) Nanofiber Membranes with Annonamuricata and Terminalia catappa Leaf Extract Fitria, Silfiyana; Almafie, Muhammad Rama; Alfikro, Ihsan; Monado, Fiber; Sriyanti, Ida; Royani, Idha
Science and Technology Indonesia Vol. 10 No. 3 (2025): July
Publisher : Research Center of Inorganic Materials and Coordination Complexes, FMIPA Universitas Sriwijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.26554/sti.2025.10.3.837-846

Abstract

Polyvinyl alcohol (PVA) is hydrophilic, flexible, elastic, and environmentally friendly, leading to the wide use as a binder in nanofiber matrices. The nanofibers of PVA are frequently combined with extract possessing antibacterial properties for characterization. Therefore, this study aimed to produce PVA nanofibers incorporating soursop leaf extract (ALE) and catappa leaf extract (CLE) using electrospinning for the investigation of the physicochemical, mechanical, and antibacterial properties. Electron microscopy showed that the electrospun nanofibers had a yellowish-brown surface with diameters ranging from 962 nm to 1323 nm. Fourier Transform Infrared (FTIR) analysis revealed the presence of functional groups interacting through hydrogen bonding, leading to a shift in wavenumbers. The tensile strength of PAC-1, PAC-2, and PAC-3 nanofibers decreased from 8.46 MPa to 4.27 MPa, followed by a reduction in Young’s modulus from 20.2 MPa to 0.89 MPa. The effect of extract concentration on the reduction in tensile strength and Young’s modulus was related to aggregation in certain areas of the nanofibers and weakened intermolecular polymer interactions. Pure extract had strong antibacterial activity and nanofiber membranes had moderate activity with inhibition zones ranging from 12.3 to 16.8 mm and 8.0 to 14.4 mm, respectively. The results showed that the produced fibers could be used in the biomedical field for wound dressings and filtration, as well as in textiles.
Ensemble Method of Multiple Decision Trees with Crisp and Fuzzy Discretization for Axial Surface Roughness Prediction Resti, Yulia; Yani, Irsyadi; Puspitasari, Dewi; Thamrin, Ismail; Saputra, M.A. Ade
Science and Technology Indonesia Vol. 10 No. 3 (2025): July
Publisher : Research Center of Inorganic Materials and Coordination Complexes, FMIPA Universitas Sriwijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.26554/sti.2025.10.3.678-689

Abstract

AISI 1045 is a steel used to make engine components for motor vehicles and aircraft. The quality of AISI 1045 is influenced by its surface roughness, both axial and tangential. The prediction of AISI 1045 surface roughness aims to produce quality products in a shorter time and at a lower cost. The axial surface roughness is in the form of certain grades according to ISO. This method is a prediction technique that combines several single prediction models to obtain better prediction results. In this work, the ensemble method is built using a voting system from an odd number of single prediction models of the decision trees. The proposed Single Model consists of one decision tree model with crisp discretization (DT1) and three models with fuzzy discretization (DT2, DT3, and DT4). The research data were obtained through experiments measuring the axial surface roughness of AISI 1045 steel using a wet machining system by considering cutting speed, feed motion, axial depth of cut, and tangential surface roughness. The study’s results indicate that not all proposed ensemble models are built to have better performance than single prediction models. Of the four proposed single prediction models, only one model has an accuracy above 80%, namely the decision tree model with fuzzy discretization using a combination of linear-trapezoidal fuzzy membership functions (DT4 model). The model performance based on accuracy, recall, precision, F1-score, and AUC is 80.73%, 48.53%, 73.47%, 58.44%, and 67.72%, respectively. For the four ensemble models formed from the combination of three Single decision tree models, only the combination of DT1, DT2, and DT3 does not perform better than the Single model. The other three ensemble methods have better accuracy, recall, and AUC than the performance of all proposed Single models with values of 81.33 - 82.67%, 51.62 - 55.19%, and 69.04 - 71.02%, respectively.

Page 47 of 56 | Total Record : 551

 45   46   47   48   49 

Filter by Year

2016 2026


Reset
Filter By Issues
All Issue Vol. 11 No. 1 (2026): January Vol. 10 No. 4 (2025): October Vol. 10 No. 3 (2025): July Vol. 10 No. 2 (2025): April Vol. 10 No. 1 (2025): January Vol. 9 No. 4 (2024): October Vol. 9 No. 3 (2024): July Vol. 9 No. 2 (2024): April Vol. 9 No. 1 (2024): January Vol. 8 No. 4 (2023): October Vol. 8 No. 3 (2023): July Vol. 8 No. 2 (2023): April Vol. 8 No. 1 (2023): January Vol. 7 No. 4 (2022): October Vol. 7 No. 3 (2022): July Vol. 7 No. 2 (2022): April Vol. 7 No. 1 (2022): January Vol. 6 No. 2 (2021): April 2021 Vol. 6 No. 4 (2021): October Vol. 6 No. 3 (2021): July Vol. 6 No. 1 (2021): January Vol. 5 No. 4 (2020): October Vol. 5 No. 3 (2020): July Vol. 5 No. 2 (2020): April Vol. 5 No. 1 (2020): January Vol. 4 No. 4 (2019): October Vol 4 No 3 (2019): July Vol 4 No 2 (2019): April Vol. 4 No. 2 (2019): April Vol. 4 No. 1 (2019): January Vol. 3 No. 4 (2018): October Vol. 3 No. 3 (2018): July Vol. 3 No. 2 (2018): April Vol. 3 No. 1 (2018): January Vol. 2 No. 4 (2017): October Vol. 2 No. 3 (2017): July Vol. 2 No. 2 (2017): April Vol. 2 No. 1 (2017): January Vol. 1 No. 1 (2016): October More Issue