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INVESTIGATION OF THE EFFECT OF SANDBLASTING WASTE TREATMENT METHOD AS NANO-SILICA ON THE COMPRESSIVE STRENGTH OF CONCRETE MORTAR
Get PDFThis study presents the effect of nano-silica (NS) from sandblasting waste as an additive on the mechanical properties of concrete mortar. The nano-silica was produced by using the sol-gel and mechanical grinding methods. In this research, nano silica material was added as an additive with a percentage varying from 0% to 5%. The results show that producing nano silica from sandblasting waste with a combination of sol-gel and mechanical grinding methods can produce an average size of 148.9 nm with 96.90% purities silica (SiO2). The compressive strength test also shows that adding NS can increase the compressive strength of the concrete. The highest compressive strength obtained from this research was. 29.76 MPa with the addition of 1% of nano-silica. This compressive strength is 37.5% higher than the control mixture
Optimizing Injection Molding Parameters to Cycle Time of Bioring Cone Cup Products with Taguchi Method
Get PDFAt the Sukodono molding company which produces Bioring cone cups using injection molding machines, a trial and error process to obtain parameter setting values on the machine is still applied in the early stages of production. This problem is detrimental to the company because they have to bear the production burden due to production delays. A solution is needed to optimize injection parameters with cycle time response. Therefore, this study proposes an analysis of the application of the Taguchi method by utilizing the signal for noise ratio to determine the influence of factors and also to optimize parameter such as temperature, pressure, and cooling time for the production process. The trial results show that the ideal blend of factors includes injection pressure parameters at level 1 with a value of 80 bar, injection temperature at level 2 in value of 225°C, and cooling time in level one with a value of 0.1 seconds
The Effect of a Mixture of Bioethanol with Octane 92 Fuel on Gasoline Engine Vibration
Get PDFAlong with technological developments, the system in vehicle engines is also experiencing developments, with the technology embedded in vehicle engines it is hoped that vehicles can become more efficient, powerful, produce low emissions, even vibration and sound produced is very small. This also needs to be supported by using the right fuel. Bioethanol is an alternative fuel made from vegetable and can produce complete combustion. The data collection method is by recording the proportion of the bioethanol mixture with 92 octane fuel and changes in engine speed, when vibrations occur, the LCD vibration meter will display the vibration value. Engine speed starts from 1500 to 8500rpm with a change of 1000rpm each rotation. From the tests carried out, at engine speed of 1500 to 2500 rpm the 5% mixture is a good mixture because the vibration value is lower than before mixing. Then for engine speed of 3500 to 8500 rpm a 10% mixture is a good mixture because the vibration value is lower than before mixing and lower than other mixtures
Diversity of Purse Seine Vessels at Pekalongan Archipelago Fisheries Port (PPN) Above 100 Gross Tonnage
Get PDFThis research aims to determine the diversity of purse seine vessels based on gross tonnage measurements which was carried out from April 2023 to July 2023. This study collected sampling data on purse seine vessels in the Pekalongan PPN, both when the vessels were berthed, and collective data sourced from the authorities Archipelago Fishing Port (PPN) Pekalongan. In this formulation, it begins with identifying the dimensions of the ship, measuring the volume of the fish hold and interviewing a number of crew members who work on the ship. The aim of this research is to identify the main dimensions of ships and describe the operation of purse seine ships. with an average ship size of over 100 gross tonnages to 200 gross tonnages with a crew of 35 to 40 people
Conversion of Waste Cooking Oil Combined With Corn Oil Into Biodiesel Using the Transesterification Method
Get PDFThis research endeavors to explore a novel alternative fuel source by combining waste used cooking oil and corn oil to create a biodiesel blend. The study addresses two main objectives: first, to investigate the properties of used cooking oil biodiesel with the addition of methanol and NaOH catalysts, and second, to assess engine performance using the biodiesel blend. The experimental approach employs transesterification, varying the catalyst quantity during biodiesel production. Preceding diesel engine testing, properties such as viscosity are assessed, revealing improved values meeting Indonesian National Standards post-catalyst addition, albeit with a decrease in calorific value. Engine performance is then evaluated, demonstrating that as the catalyst content increases, torque and thermal efficiency decrease, while specific fuel consumption (SFC) rises. Notably, the study concludes that a higher catalyst ratio aligns fuel properties closer to government-set standards. The most favorable engine performance is observed in the B50 sample with a catalyst variation of 1000 ml of methanol and 25 g of NaOH, showcasing superior torque, thermal efficiency, and opacity values compared to higher catalyst variations. This research underscores the importance of catalyst optimization in achieving an environmentally friendly biodiesel blend with enhanced engine performance
Design and Fabrication of Composite Monocoque Chassis for Formula Student Racing Car
Get PDFThis study uses a combination of analytical, simulation, and experimental methods in the design process of a sandwich-structured composite monocoque chassis. The analytical method, which determines the stiffness value of the composite, depends on the number of layers and the orientation of the fiber angle. The simulation method, which is based on the finite-element method, is used to validate the stiffness value. The experimental method involves a 3-point bending test used to verify the effectiveness of the design produced by analytical and simulation methods. After all model designs were validated through simulation and experimental methods, the next stage is fabrication. The stiffness and strength are achieved with variations, which have combined layup orientation angles of 0° and 45°. This can be applied to all panels, regardless of the number of layers. Based on the design results, the processes involved in fabricating the monocoque chassis begin with the manufacture of molds and the lay-up of carbon fiber. The process is continued by inserting the prototype into the oven, after which the final product then undergoes finishing to prepare it for use. The fabricated monocoque chassis has been used in 2 events in Japan’s annual Formula SAE student racing car competition
Peningkatan kualitas layanan perbankan digital melalui pengelompokan tweet menggunakan DBSCAN
Get PDFDigitalization in the banking sector allows customers to obtain banking services independently without having to come directly to the bank. Digital banking services enable customers to obtain information, communicate, register, open accounts, banking transactions and close accounts, including obtaining other information and transactions outside of banking products. Banking is intensively providing services or promotions through social media, one of which is by using Twitter social media. Density-Based Spatial Clustering of Applications with Noise (DBSCAN) method. DBSCAN clustering is done by combining the Eps and MinPts values to produce the highest silhouette coefficient. The highest silhouette coefficient values from BRI, Mandiri and BCA banking service tweets produce 33, 14, and 39 clusters, respectively, with different Eps and MinPts values. Based on the results of wordcloud, it shows that banking services need to be improved in terms of checking DM on accounts, customers ask the admin to immediately respond to complaints related to ATM cards, disruptions to mobile banking and some say thank you for the services that have been provided
Greenhouse Potential based on Ecotourism and Education for Sustainable Village Economic Resilience
Get PDFIndonesia has many rural areas with diversity and uniqueness in each region that have developed into eco-tourism. The village that is being developed as an eco-tourism destination is expected to improve the welfare of the surrounding community. Developed eco-tourism can provide jobs for residents in the village. Eco-tourism is also one of the developments to preserve ecosystems in rural areas. This eco- tourism sector can support community welfare and sustainable rural development. One approach to the development of rural areas is through village ecotourism. Village Ecotourism is a rural area with several special characteristics that can be used as a tourist destination. One way to improve the development of village ecotourism is by adding new facilities that lead to educational tourism, i.e., greenhouse facilities. The existence of this greenhouse can be used as a means of science education about a more advanced agricultural system with a controlled environmental system. Greenhouse technology can improve the quality and quantity of plant productivity, thereby increasing people's income, and producing healthier organic plant products. Greenhouses can also be used as educational tourism facilities for various science education activities and simple agricultural training. Training for residents can also be carried out, for community empowerment, such as training in planting, fertilizing, nurseries, processing plant products, and the process of packaging plant products. This review summarizes the various potentials of Greenhouse development for the development of education-based village ecotourism and provides references for further research that focuses on community service, which is increasing sustainable village economic resilience
Generalized Space Time Autoregressive Integrated Moving Average (GSTARIMA) dalam Peramalan Data Curah Hujan di Kota Makassar
Get PDFModeling of rainfall data using time series data involving location elements has not been widely carried out. One model that involves elements of time and location is Space Time Autoregressive (STAR). The development of the STAR model which assumes that each location has heterogeneous characteristics is the Generalized Space Time Autoregressive Integrated Moving Average (GSTARIMA) model. The purpose of this research is to get the best GSTARIMA model and forecast rainfall data in Makassar City based on the best GSTARIMA model. This model incorporates time and geographic dependencies with different parameters for each location. The data used is Makassar city's monthly rainfall data at the Bawil IV/Panaikang, Biring Romang/Panakkukang and Stammar Paotere rain stations from January 2017 to September 2021. Autoregressive (AR) and Moving Average (MA) orders were identified using the Space Time Autocorrelation plot. Function (STACF) and Space Time Partial Autocorrelation Function (STPACF). The spatial order used in this study is spatial order 1 with an inverse distance weighting matrix and normalized cross-correlation. Parameters were estimated using the Generalized Least Squares (GLS) method. The best model for predicting rainfall in the city of Makassar is the GSTARIMA (1,0,0) (1,1,0)12 model using an inverse distance weighting matrix with the smallest average Root Mean Square Error (RMSE) of 132.9661
Penggunaan Metode Cost Significant Model Untuk Memprediksi Biaya Pembangunan Jalan Baru
Get PDFInfrastruktur jalan merupakan salah satu aspek penunjang pertumbuhan ekonomi wilayah karena berkaitan secara langsung pada proses distribusi barang dan jasa. Pembangunan infrastruktur jalan membutuhkan proses perencanaan yang matang agar proyek dapat berjalan dengan optimal. Penelitian ini bertujuan untuk mengembangkan model prediksi biaya pembangunan jalan baru di Provinsi D.I. Yogyakarta dengan fokus pada tahun 2017-2023. Penelitian ini menggunakan Metode Cost Significant Model yang berfokus pada sembilan proyek pembangunan jalan di Provinsi D.I. Yogyakarta. Data penelitian diperoleh dari harga penawaran proyek pembangunan jalan baru di Provinsi D.I. Yogyakarta tahun 2017-2023. Analisis data menggunakan pendekatan Regresi Linier Berganda yang kemudian dikembangkan menjadi dasar pemodelan dalam estimasi Cost Significant Model. Hasil penelitian menunjukan bahwa terdapat empat variabel yang memiliki pengaruh signifikan pada proyek pembangunan jalan baru yaitu: Pekerjaan Tanah (X3), Pekerjaan Aspal (X6), Pekerjaan Struktur (X7), dan Perkerasan Berbutir (X5). Model Estimasi yang terbentuk dari Cost Significant Model dalam penelitian ini yaitu; Y = 3.438,327 + 0,785X3 + 0,863X6 + 1,160X7 + 3,021X5. Tingkat keakuratan (persentage error estimate) hasil estimasi Cost Significant Model dalam penelitian ini berkisar antara -5,00% sampai +4,72%