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INDONESIA
Indonesian Journal of Science and Technology
Published by Universitas Pendidikan Indonesia
ISSN : 25278045     EISSN : 25281410     DOI : -
Core Subject : Science, Social,
Computer Science & IT Environmental Science
Arjuna Subject : -
Articles 216 Documents
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Synthesis, Characterization, and Electrochemical Performance of Reduced Graphene Oxide-Metal (Cu,Zn)-Oxide Materials Sugianto Sugianto; Ngurah Made Dharma Putra; Endah F. Rahayu; Wahyu B. Widayatno; Cherly Firdharini; Slamet Priyono; Didik Aryanto
Indonesian Journal of Science and Technology Vol 8, No 2 (2023): (ONLINE FIRST) IJOST: September 2023
Publisher : Universitas Pendidikan Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17509/ijost.v8i2.56065

Abstract

The reduced graphene oxide (rGO) and metal (Cu,Zn)-oxide composites were prepared using a one-step hydrothermal technique. The role of (Cu,Zn)-oxide on the physical and electrochemical properties of the composite was investigated. The composite consists of various shapes of ZnO nanoflowers and micro-spheres, as well as Cu-oxide nanoflakes and octahedron-like shapes. The (Cu,Zn)-oxides were formed in between the rGO layers and observed in the rGO-ZnO, rGO-CuO, and rGO-CuO-ZnO composites. The presence of ZnO, CuO, and rGO within the composite structure is also confirmed by the analyses of crystal structure, microstructure, and surface functional groups. Some excess impurities remaining from the surfactant give considerable differences in the electrochemical performance of the composites. The specific capacitance values of the rGO, rGO-ZnO, rGO-CuO, rGO-(0.5CuO-0.5ZnO), and rGO-(0.25CuO-0.75ZnO) composites are 9.32, 58.53, 54.14, 25.21, and 69.27 F/g, respectively. The formation ofa double metal-oxide structure as well as their insertion into the rGO sheet can significantly improve the electrochemical properties of the supercapacitor.
Management Information Systems: Bibliometric Analysis and Its Effect on Decision Making Budi Santoso; Try Hikmawan; Nani Imaniyati
Indonesian Journal of Science and Technology Vol 7, No 3 (2022): IJOST: December 2022
Publisher : Universitas Pendidikan Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17509/ijost.v7i3.56368

Abstract

Decision-making in the organization always relates to the description of the results of the decisions taken. Therefore, every organization needs a management information system to assist in making various kinds of decisions needed. The purpose of this study was to determine the influence and effectiveness of management information systems on decision-making in the field of archives. The method used in this study is the explanatory survey method. Data collection techniques were carried out using questionnaires and product correlation moments. Data analysis was performed using simple regression analysis and hypothesis testing. The subjects of this study were 120 administrative employees in the city of Bandung. To support the analysis, this study also carried out a bibliometric analysis to determine trends in research development from information management systems to decision-making. Based on the findings, the quality of the management information system used is in the high category, as well as the effectiveness of decision-making is in the high category. Based on the results of hypothesis testing and significance, it can be interpreted that the management information system has a positive and significant effect on decision-making in the field of administration.
Bifunctional CaCO3/HY Catalyst in the Simultaneous Cracking-Deoxygenation of Palm Oil to Diesel-Range Hydrocarbons Rosyad Adrian Febriansyar; Teguh Riyanto; I. Istadi; Didi D. Anggoro; Bunjerd Jongsomjit
Indonesian Journal of Science and Technology Vol 8, No 2 (2023): (ONLINE FIRST) IJOST: September 2023
Publisher : Universitas Pendidikan Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17509/ijost.v8i2.55494

Abstract

Palm oil is a promising raw material for biofuel production using the simultaneous catalytic mechanism of the bifunctional cracking-deoxygenation reactions. Through the cracking-deoxygenation process, the chains of palmitic acid and oleic acid in the palm oil were converted to diesel-range hydrocarbons. The combination effects of CaCO3 and HY zeolite enhanced the bifunctional catalytic cracking-deoxygenation of palm oil into biofuel, because of the increasing acid and basic sites in the catalysts due to the synergistic roles of CaCO3 and HY. The introduction of CaCO3 on HY zeolite generated both a strong acid and strong basic sites simultaneously on the designed catalyst, which supports the bifunctional mechanisms of hybrid cracking-deoxygenation, respectively. The CaCO3 impregnated on the HY catalyst has a synergistic and bifunctional effect on the catalyst supporting cracking-deoxygenation reaction mechanisms as mentioned previously. The deoxygenation reaction required the bifunctional strong acid and strong basic sites on the CaCO3/HY catalyst through decarboxylation, decarbonylation, and hydrodeoxygenation reaction mechanisms. Meanwhile, the cracking reaction pathway was supported by the strong acid sites generated on the CaCO3/HY catalyst. In other words, the high acidity strength promotes diesel selectivity, whereas the high strength of basicity leads to the deoxygenation reaction.
Predicting Consumption Intention of Consumer Relationship Management Users Using Deep Learning Techniques: A Review Eshrak Alaros; Mohsen Marjani; Dalia Abdulkareem Shafiq; David Asirvatham
Indonesian Journal of Science and Technology Vol 8, No 2 (2023): (ONLINE FIRST) IJOST: September 2023
Publisher : Universitas Pendidikan Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17509/ijost.v8i2.55814

Abstract

Consumer/customer relationship management (CRM) can potentially influence business as it predicts changes in people’s perspectives, which could impact future sales. Accordingly, advancements in Information Technology are under investigation to see their capabilities to improve the work of CRM. Many prediction techniques, such as Data Mining, Machine Learning (ML), and Deep Learning (DL), were found to be utilized with CRM. ML methods were found to dominate other approaches in terms of the prediction of consumers’ intention to purchase. This review provides DL algorithms that are mostly used in the last five years, to support CRM to predict purchase intention for better product sales decisions. Prediction criteria related to online activities and behavior were found to be the most inputs of prediction models. DL approaches are slowly applied within purchase intention prediction due to their advanced capabilities in handling large and complicated datasets with minimum human supervision. DL models such as CNN and LSTM result in high accuracy in prediction intention with 98%. Future research uses the two algorithms (CNN, LSTM) compiled to make the best prediction consumption in CRM. Additionally, an effort is being made to create a framework for predicting purchases based on many DL algorithms and the most pertinent characteristics.
How to Calculate and Measure Solution Concentration using UV-Vis Spectrum Analysis: Supporting Measurement in the Chemical Decomposition, Photocatalysis, Phytoremediation, and Adsorption Process Asep Bayu Dani Nandiyanto; Risti Ragadhita; Muhammad Aziz
Indonesian Journal of Science and Technology Vol 8, No 2 (2023): (ONLINE FIRST) IJOST: September 2023
Publisher : Universitas Pendidikan Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17509/ijost.v8i2.57783

Abstract

UV-visible (UV-Vis) spectroscopy is a powerful instrument for qualitative investigation and quantitative detection of pollutants in water. UV-Vis spectrophotometry is an analytical method using the concept of transmission of light in UV and Visible wavenumber. Generally, compounds can be identified using UV-Vis Spectrophotometry, based on the concept of light absorption, specifically for compounds with a chromophore group and an auxochrome group. Although the utilization of UV-Vis spectrum analysis has been well-documented, no information regarding detailed step-by-step measurement for examining detailed quantitative analysis, particularly in determining the concentration of an analyte in an aqueous solution sample. Here, this study explores the idea and application of UV-Vis technology in water quality detection, including guidelines for determining the concentration of the sample in an aqueous solution. To support the analysis, we also added practical examples for understanding concentration during the organic decomposition. This paper is intended to be useful for researchers and students in understanding UV-Vis spectrophotometry when analyzing chemical composition during chemical decomposition, photocatalysis, phytoremediation, and adsorption analysis.
How to Purify and Experiment with Dye Adsorption using Carbon: Step-by-Step Procedure from Carbon Conversion from Agricultural Biomass to Concentration Measurement Using UV Vis Spectroscopy Asep Bayu Dani Nandiyanto; Meli Fiandini; Risti Ragadhita; Muhammad Aziz
Indonesian Journal of Science and Technology Vol 8, No 3 (2023): (ONLINE FIRST) IJOST: December 2023
Publisher : Universitas Pendidikan Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17509/ijost.v8i3.58290

Abstract

This paper contains guidelines and provides a basic understanding of how to do experiments in dye adsorption using carbon. This paper presents a step-by-step experimental procedure from carbon preparation (as biochar) from agricultural waste to concentration measurement using UV-Vis Spectroscopy. We used agricultural waste as a model due to its high cellulose and organic content, making it easily converted into carbon. This paper can be used as a guide for researchers and students in the fabrication of carbon from agricultural waste biomass easily and inexpensively for its application as an adsorbent in the batch adsorption process. This paper also supports the current issues in Sustainable Development Goals (SDGs).
A Conceptual Curriculum Design Approach for Educating Engineers of and for the Future Satesh Namasivayam; Abdulkareem Sh. Mahdi Al-Obaidi; Mohammad Hosseini Fouladi
Indonesian Journal of Science and Technology Vol 8, No 3 (2023): (ONLINE FIRST) IJOST: December 2023
Publisher : Universitas Pendidikan Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17509/ijost.v8i3.59580

Abstract

The 4th Industrial Revolution (I4) highlights the demand for engineers equipped with technical expertise, emotional intelligence, communication, leadership, and critical thinking skills to navigate the complexities of modern engineering. This conceptual paper presents a future-oriented approach to engineering curriculum development, emphasizing the adoption of Outcome-Based Education (OBE) and project-based learning. The integration of key frameworks, such as the Conceive Design Implement Operate (CDIO) model and blended learning techniques, enhance the learning experience. The curriculum aims to align with global goals, including the UN Sustainable Development Goals and the 14 Grand Challenges for Engineering. An innovative curriculum is designed to inspire students' passion for engineering and engage them with emerging technologies, such as additive manufacturing and artificial intelligence. By equipping graduates with the necessary skills and knowledge, this curriculum strives to make a significant impact on society, fostering sustainability and addressing complex engineering challenges. This paper contributes to the field of engineering education by providing a comprehensive and forward-thinking approach to curriculum development.
Adsorption of Sodium in an Aqueous Solution in Activated Date Pits Zakaria Rahal; Abderrahmane Khechekhouche; Ayoub Barkat; Smolyanichenko Alla Sergeevna; Chekima Hamza
Indonesian Journal of Science and Technology Vol 8, No 3 (2023): (ONLINE FIRST) IJOST: December 2023
Publisher : Universitas Pendidikan Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17509/ijost.v8i3.60066

Abstract

The use of acid-activated local date pits from Algeria's Oued Souf region for reducing water salinity by removing sodium. The raw and activated date pits were characterized using XRD, FTIR, SEM, and BET. The study used these materials to adsorb sodium from aqueous water, with the effects of activation time, initial sodium concentration, adsorption time, and pH of the solution on sodium removal being investigated. The specific surface area of natural date pits was found to be 645.46 m2/g, while activated date pits had a maximum of 825.03 m2/g. The maximum sodium adsorption capacity was observed at an adsorption time of 90 min, Na+ concentration of 600 mg/L, solution pH of 9.0, and adsorbent dosage of 0.1 g. The equilibrium data obtained from the experiment were analyzed using Langmuir and Freundlich isotherm models. The findings revealed that among the isotherm models examined, the Freundlich isotherm model demonstrated the strongest fit, exhibiting a high correlation coefficient of 0.999. Furthermore, the adsorption kinetics were investigated through the analysis of the pseudo-first-order and pseudo-second-order models, and the results indicated that the pseudo-second-order model provided the most suitable fit, with a correlation coefficient of 0.996.
Multi-Distributed Activation Energy Model for Pyrolysis of Sugarcane Bagasse: Modelling Strategy and Thermodynamic Characterization Siti Jamilatun; Muhammad Aziz; Joko Pitoyo
Indonesian Journal of Science and Technology Vol 8, No 3 (2023): (ONLINE FIRST) IJOST: December 2023
Publisher : Universitas Pendidikan Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17509/ijost.v8i3.60175

Abstract

The multi-distributed activation energy model (multi-DAEM) is the most effective approach for outlining the kinetics model of biomass pyrolysis. The purpose of this study is to identify the optimal number and shape of the DAEM for sugarcane bagasse pyrolysis and to discuss its thermodynamic characteristics using the combination of multi-DAEM and differential thermal analysis (DTA). The heating rate of 10, 30, and 50 °C/min was employed. The results revealed that the multi-DAEM with five pseudo components and Weibull distribution shape gave the lowest relative root mean of the squared error (RRMSE) of 0.66% and 0.41%, respectively. Kinetic and thermodynamic studies showed that the 1st and 4th pseudo components which represent lignin, have activation energy (E0) of 189.6 and 180.6 kJ/mol, and less endothermic or possibly exothermic properties. Meanwhile, the 2nd, 3rd, and 5th pseudo components which represent cellulose, hemicellulose, and moisture have activation energy (E0) of 176.1, 152.2, and 145.6 kJ/mol, respectively, and endothermic properties.
Assessment of Iron Contamination in Groundwater of Catchment Area Water Aichetou Brahim Boutebib; Abdoulaye Demba N’diaye; Sid’Ahmed Baba Elhoumed; Bocar Kalidou M’Baye; Youssef Aoulad El Hadj Ali; Belkheir Hammouti; Bakari Mohamed Semega
Indonesian Journal of Science and Technology Vol 8, No 3 (2023): (ONLINE FIRST) IJOST: December 2023
Publisher : Universitas Pendidikan Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17509/ijost.v8i3.60560

Abstract

This study investigates the occurrence of iron (Fe) in the catchment area water in Derwiche from Hodh El Chargui in Mauritania. The study area was monitored during January and August. The occurrence of Fe in the groundwater showed significant spatial and temporal fluctuations. The relationship between Fe and some physicochemical parameters was also analyzed statistically using Pearson’s correlation matrix. Firstly, the results suggested that the concentration of Fe was influenced by the dissolution of iron minerals. Secondly, the results show that the pH value was an important factor that influenced the Fe concentrations in the groundwater. The Water Quality Index (WQI) method was used to evaluate the suitability for human consumption. The results show that WQI is strongly influenced by Fe indicating that Fe removal would contribute to excellent well water. The Treatability Index (TI) is used to assess water quality. TI confirms the results obtained by the WQI. However, TI also shows that the pH is a parameter to be optimized for possible potabilization. These results show that there would be a close relationship between the recorded Fe levels and the pH. TI confirms the results obtained by Pearson’s correlation matrix. Therefore, the presence of high Fe concentrations in groundwater in the study area could have a natural origin. The results recommended that different treatment techniques should be employed to purify groundwater before consumption. The primary focus should be cascaded toward Fe contamination.

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