Aceh International Journal of Science and Technology
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Electric Car Battery Waste in Indonesia: Projections and Management Policies
Full text linkGlobal trends in electric vehicle adoption have been increasing significantly in recent years. In Indonesia, the government has issued various policies to encourage the use of electric cars. However, anticipation of the environmental impact of this program has not yet received serious attention. Current regulations regarding battery waste management still refer to existing regulations governing hazardous and toxic waste. This study aims to forecast the potential of battery waste from electric cars in the future and provide policy recommendations to establish a sustainable electric car program. The methods of analysis employed include material flow analysis and policy content analysis. Based on three scenarios (low, medium, and high adoption scenarios), the analysis results show a significant increase in battery waste in all scenarios from 2025 to 2040. The increase in active materials, aluminum, and copper waste could exceed 50 times during this period. Electrolyte, plastic, and steel waste also increase substantially, with growth reaching 3050 times. Although relatively small in volume, rare earth metals are projected to rise 19 times. By 2040, the potential of battery waste is estimated to reach 1,998,911 tons in a low adoption scenario, 2,600,540 tons in a medium adoption scenario, and 3,170,517 tons in a high adoption scenario. The result of policy content analysis of the electric vehicle regulations issued by the Indonesian government since 2019 demonstrates that efforts to enhance electric vehicle adoption will become the main focus for the government in the coming years. A thematic mapping of policies related to 20 electric vehicle regulations published during this period reveals that only three regulations address environmental issues. This study indicates the need for policy improvements by formulating specific derivative regulations that govern electric car battery waste management
The Evaluation of Prefabricated Vertical Drain (PVD) Installation Effect on Soft Soil Physical and Mechanical Properties
No full textThe purpose of the Yogyakarta - Bawen Toll Road construction was to improve connectivity between Yogyakarta and Semarang. However, during its construction, soft soil problems were found, so Prefabricated Vertical Drains (PVD) were installed. The installation of PVD aims to increase the rate of pore water discharge from the soil, thereby compacting it and enhancing its bearing capacity. Changes in soil material parameters also accompany this increase in bearing capacity. This study was conducted to analyze the effect of PVD installation on the physical and mechanical properties of the soil. The analysis was conducted by comparing soil investigation data before and after the PVD installation. Soil sample data were collected from the Yogyakarta-Bawen Toll Road, STA 4+500, specifically at BH 17. The physical properties under review are water content, wet unit weight, soil specific gravity, Atterberg limits, and changes in particle composition as determined by grain size analysis. Meanwhile, changes in the mechanical properties of the soil include pre-consolidation pressure, compression index, recompression index, consolidation coefficient, and volume compressibility. Undrained shear strength parameters were measured using an unconfined compression test to identify the soil's bearing capacity. The results show changes in physical and mechanical parameters before and after PVD installation. Overall, the most critical aspect of the accelerated consolidation method for physical parameters is a decrease in water content of 13% to 37% compared to the pre-PVD installation condition. Meanwhile, changes in the consolidation parameters, as well as a decrease in unconfined compressive strength of 2% to 12%, are also observed. This occurs for various reasons, one of which is the relationship between the completion time of the consolidation process and the consolidation process. However, the soil classification remained the same, according to the USCS, as a very stiff soil typ
Estimation of Geothermal Potential Area in Kabawetan Sub-District, Using 2D Magnetotelluric Inversion Method
No full textKabawetan is located in the subduction zone of the magmatic arc in the Indonesian tectonic system. The geothermal energy potential in this region is closely tied to volcanic activity, which is prevalent along the Ring of Fire on the island of Sumatra. This study aims to identify the distribution of subsurface resistivity values related to geothermal potential in the Kabawetan Region. To achieve this, the magnetotelluric (MT) method is used, utilizing electrical and magnetic sensors. Data were collected using two horizontal electrical sensors (Ex, Ey) and three magnetic sensors, including two horizontal sensors (Hx, Hy) and one vertical sensor (Hz). Measurements using the magnetotelluric method can be used to determine the subsurface rock layers based on resistivity values. The results of data processing yield a 2D cross-section of the resistivity value, which characterizes the potential for geothermal energy. This study used four measurement points to analyze resistivity variations and determine geothermal potential. Field measurement data were processed using MAPROS software, and a 2D cross-section model was created using ZONDMT2D. The results showed that resistivity values of 20-60 m, thought to be impermeable overburden, were at depths of 0-1.5 km and 2.5-4 km, resistivity values of 0.54-1 m indicated permeable reservoirs at depths of 1.5-2.5 km, and resistivity values of 290-550 m indicated geothermal rocks at depths of 4-10 km. The findings of this research are expected to enhance the understanding of geothermal energy as a renewable resource, thereby supporting the Sustainable Development program
Characterization of Natural Fiber Reinforced Resin Composites and Glass Waste Powder for Brake Linings
Full text linkCurrently, there are two types of brake linings in the market: asbestos brake lining and asbestos-free brake linings. The asbestos Brake lining was widely used due to durability, heat resistance and friction properties. In terms of price, asbestos brake linings are indeed cheaper than asbestos-free brake linings, However, they have negative impact on the environment and human health. In high enough concentrations, asbestos dust can cause Mesothelioma, a malignant tumor in the lining of the lungs). Therefore, it is necessary to find a substitute material for asbestos that is affordable but possesses similar characteristics to asbestos brake linings. While, the high production of salak in Indonesia has a side effect, i.e.: the large volume of waste in the form of peel and seeds of salak. If not utilized, of course this will become waste. Meanwhile, glass waste is an inorganic waste material that is very difficult to decompose and pollutes the environment. Meanwhile, glass waste is one of the inorganic waste materials that is very difficult to decompose and pollutes the environment. The aim of this study was to characterize composite resin materials reinforced with glass waste powder, Snake Fruit Peel Powder and teak wood sawdust as alternative brake lining materialsThe research was conducted through laboratory experiments, beginning with the manufacture of sample specimens, followed by measuring their density, hardness, and friction coefficient testing then compared to brake lining on the market and also based on the SNI 09-0143-1987 standard. The result showed, some of the investigated samples in this study meet the reqirement of SNI 09-143-1987, where the lowest Brinell Hardness number of the sample 120.33. There are 5 specimens of friction coefficient of the specimens are also fullfill the requirement
Enhancing Proppant Properties of Silica from Rupat Island Using Epoxy and Polyester Resins: A Comparative Study Based on API 19C
No full textoai:jurnal.usk.ac.id:article/47254This study evaluates the potential of silica sand from Rupat Island, Indonesia, as a natural proppant for hydraulic fracturing, based on API RP 19C standards. Samples tested include unmodified sand, epoxy-coated sand (5% and 10%), and polyester-coated sand (5% and 10%). Key parameters assessed were roundness and sphericity, bulk density, turbidity, acid solubility, and crush resistance. Uncoated silica showed substandard morphology (0.47), while resin-coated samples reached 0.53 and polyester resin reached 0.54, meeting API criteria. Bulk density ranged from 1.53 to 1.60 g/cc, and turbidity values (2038 NTU) were within acceptable limits. This study demonstrates that applying a resin coating to Rupat silica sand notably enhances its physical and chemical properties, making it more suitable for use as a proppant. The coated sand exhibited an increase in bulk density, reaching 1.581.60 0.01 g/cc, which exceeds the API RP 19C minimum standard of 1.5 g/cc and suggests improved packing efficiency. Additionally, the acid solubility dropped from 2.8% in the uncoated sand to 1.22 0.01% in the coated samples, reflecting greater chemical resistance. Turbidity levels remained low, ranging from 20 to 135 2 NTU, well below the API limit of 250 NTU, indicating minimal generation of fine particles. In crush resistance tests, uncoated sand lost up to 13% weight at 5000 psi, while resin-coated variants showed improved performance, with weight loss reduced to 814% (5 mL and 10 mL epoxy resin) and 512% (5 mL and 10 mL polyester) at 6000 psi and 8000 psi. These results confirm that with appropriate surface modification, Rupat silica sand meets key API 19C criteria and holds strong potential as a local proppant material for hydraulic fracturingTRANSLATE with x EnglishArabicHebrewPolishBulgarianHindiPortugueseCatalanHmong DawRomanianChinese SimplifiedHungarianRussianChinese TraditionalIndonesianSlovakCzechItalianSlovenianDanishJapaneseSpanishDutchKlingonSwedishEnglishKoreanThaiEstonianLatvianTurkishFinnishLithuanianUkrainianFrenchMalayUrduGermanMalteseVietnameseGreekNorwegianWelshHaitian CreolePersian// TRANSLATE with COPY THE URL BELOW Back EMBED THE SNIPPET BELOW IN YOUR SITE Enable collaborative features and customize widget: Bing Webmaster PortalBack/
Effect of Angle of Attack on Drag and Lift Coefficients on Naca Airfoil for Wind Turbine Application
No full textThe development of renewable energy is expected not only to reduce dependence on fossil fuels but also to support the transition toward cleaner and more sustainable energy systems in the future. The combustion of fossil fuels significantly contributes to greenhouse gas emissions, thereby accelerating global climate change. Recognizing these limitations and negative environmental impacts, researchers and energy experts have begun to explore and develop various alternative energy sources that are more environmentally friendly and sustainable. Among them, wind energy is one of the most promising and widely available clean energy resources. The efficiency of wind turbines can be enhanced by optimizing the aerodynamic characteristics of their blades. This study examines the aerodynamic properties of three distinct NACA airfoil profiles: NACA 0012, NACA 2412, and NACA 3412. These profiles differ in camber magnitude and distribution, yet they share a maximum thickness of 12% of the chord length. Computational Fluid Dynamics (CFD) simulations were conducted using ANSYS Fluent with angles of attack ranging from -20 to 20. The results reveal that the NACA 2412 airfoil demonstrates the best aerodynamic performance at an angle of attack of 5, achieving the highest lift-to-drag ratio (L/D)
Monitoring Forest Cover Loss Due to The Impact of Mining Activities Using Google Earth Engine in West Aceh Regency
Full text linkIn recent years, forest areas in Aceh Province, especially in West Aceh Regency, have experienced a significant decline in forest cover. This can negatively impact biodiversity, community quality of life, and natural disaster risk, exacerbating global climate change. The fact that West Aceh is one of the regencies with the highest number of gold and coal mining companies in Aceh is a significant concern when assessing whether mining activities impact forest cover loss. This study aims to monitor and quantify forest cover change and the impact of mining activities in Aceh Barat from 2019 to 2024. The research methodology included the use of Google Earth Engine (GEE) for Sentinel-2 satellite image analysis by calculating the Normalized Difference Vegetation Index (NDVI); NDVI values above 0.7 were classified as forest, values below 0.7 as non-forest, and negative values as water bodies. The analysis showed that forest cover loss in West Aceh reached 13030.84 ha over the last five years at an average rate of 2606.17 ha/year. Illegal gold mining activities contributed 12.8%, legal coal mining 10.2%, and legal gold mining 7.3% to forest cover loss, while non-mining factors caused 69.7%. This study presents a cost-effective forest monitoring method that supports biodiversity protection and improved forest management policies in mining areas
Modeling and Analysis of Column Formwork Construction Components Using Dynamo Revit (Study Case : Project Construction of Building 2 Hermina Hospital Pandanaran)
Full text linkThe construction industry in Indonesia continues to experience rapid growth. However, there are still challenges in implementing Building Information Modeling (BIM) technology, particularly in the volume calculation of formwork activity. BIM for formwork activity is generally utilized to calculate the surface area of formwork. Moreover, cast-in-place concrete formwork has many components with different utilities; thus, it is difficult to manage. Therefore, this study endeavors to expand BIM by employing BIM to automate the calculation of the formwork components. This research aims to utilize Autodesk Revit and Dynamo software to accelerate calculation time and enhance the accuracy of calculating the components of column formwork. The developed model is applied in the Hermina Pandanaran Hospital Building 2 Project as reliability validation of the model. The column formwork construction is modeled using Revit in 3D format, which is subsequently analyzed using the Dynamo script to automatically obtain the complete components of the column formwork activity, including the amount of each component. A comparison of manual calculations between those performed using Dynamo shows a 0% difference percentage, demonstrating the accuracy of Dynamo calculation. Based on the result, the utilization of Revit and Dynamo has proven to increase efficiency in formwork management. The findings of this research can provide insights into construction practitioners to leverage BIM technology in enhancing the efficiency and accuracy of column formwork components' volume calculations
Hotspot Distribution in West Kalimantan Using K-Means and SOM Clustering
No full textIndonesia has quite a large forest, and some forests often experience fires. These fires typically occur due to several factors, including high solar heat, drought in peat forests, and the practice of clearing land by burning. This research focuses on West Kalimantan, one of the areas that experiences the most frequent forest fires. To achieve this, the study employs K-Means Clustering and Self-Organizing Map (SOM) algorithms, integrated with Geographic Information System (GIS) tools, to process satellite imagery from NASAs Terra and Aqua satellites. Key parameters include geographic coordinates (latitude and longitude), brightness temperature, and hotspot confidence levels. The clustering results identified two primary groups, with Cluster 2 representing the group with the highest thermal activity and fire risk. This cluster recorded a peak brightness temperature of 432.42 K and achieved a silhouette score of 0.71, indicating high clustering validity. GIS-based mapping revealed that the Sambas region had the highest concentration of hotspots, accounting for 36.01% of all detected points. These findings underscore the importance of targeted fire prevention efforts, particularly in high-risk zones with dense vegetation and frequent fire incidents
Comparative Study Of The Performance Of Dabex And Anfo Explosives Based On Fragmentation And Its Influence On Blasting Costs
No full textPT. Semen Tonasa conducts blasting using two explosives, Ammonium Nitrate Fuel Oil (ANFO) and Dahana Bulk Emulsion Explosives (DABEX), each with unique specifications that will affect fragmentation quality and blasting costs. This research evaluates the performance of ANFO and DABEX based on fragmentation quality (optimal recovery rate), which will influence blasting cost. It analyzes the best practices for each explosive in different areas. It uses photographic methods to collect fragmentation samples, which will then be analyzed to obtain optimal recovery rates and blasting costs, using rock factor data and deviation of analysis results, the best practice of each explosive can be determined. Based on the result of the analysis, in terms of fragmentation quality, DABEX explosives outperform ANFO with an optimal recovery rate of DABEX reaching 95.6% while ANFO is 89.3%, however, DABEX takes an average of Rp. 4,583 to blast one ton of limestone with a recovery rate of 95.6% while ANFO with a 89.3% recovery rate costs Rp. 3,369. It was found that better fragmentation quality results in lower costs, and vice versa. This is demonstrated by the linear regression analysis, which reveals a very strong negative correlation (R = 0.9819 for DABEX and R = 0.8917) in the relationship between the high level of recovery and the high cost of dismantling one ton of limestone. Both ANFO and DABEX can reach their maximum performance on area B8. Where the optimal recovery rate for DABEX is 95.31% with a cost/ton of Rp 4,622.75, while the optimal recovery for ANFO is 90.16% with a cost/ton of Rp 3,744.62. Meanwhile, the worst performance is predicted to occur on the northern B9 area, with the optimal recovery rate for DABEX is 94.66% with a cost/ton of Rp 4,703.06, while for ANFO the optimal recovery is 89.18% with a cost/ton of Rp 3,785.9