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Experimental Study of Plastic Waste Fuel in Diesel Engine to Overcome Fuel Shortage Towards a Green Economy Facing IMO Tier III Standards
Get PDFShips generally use diesel engines as propulsion to produce energy from the combustion process. The fuel used on ships uses diesel oil, but its use can result in marine environmental pollution. Marine environmental pollution is currently a national issue that must be addressed immediately, where the International Maritime Organization (IMO) in MARPOL Annex VI TIER III limits the content of exhaust emissions. This research is to analyze the effect on engine performance and emissions, especially NOx produced by diesel engines, then compare NOx emission data with IMO TIER III standards. This research uses an experimental method by mixing two fuels with the composition B0 (pure plastic waste), B1 (80% - 20%), B2 (70% - 30%). After conducting research the effective result is B1 fuel. Because trendline graphs are quite optimal for use on diesel engines. The power produced by B1 is 1.36 KW to 2.12 KW. SFC B1 produces 431.35 g/kWh to 352.61 g/kWh. For efficiency, B1 produces 19.3% to 23.6%. For torque, bmep, and fc produce values that are directly proportional to engine speed. The results of the NOx emissions test were obtained for each type of fuel composition, B0 was 174 gr/kWh – 185gr/kWh, B1 was 182gr/kWh – 218gr/kWh and B2 was 198gr/kWh – 224gr/kWh. This meets the MARPOL Annex TIER III standards
Faktor Pemilihan Sarana Transportasi Menuju Kampus oleh Mahasiswa ITB dan UGM
Get PDFAdanya perkembangan dan pertumbuhan laju penduduk yang terus meningkat setiap tahunnya menyebabkan peningkatan pergerakan masyarakat untuk berpindah dari satu tempat ke tempat lainnya. Salah satu faktor yaitu bertambahnya jumlah mahasiswa dalam suatu kampus yang membutuhkan transportasi sebagai sarana pergerakan. Tujuan penelitian ini adalah untuk mengetahui alasan pemilihan sarana transportasi pada mahasiswa ITB dan UGM serta membuktikan adanya korespondensi antara kondisi geografis sebuah kota dengan pemilihan sarana transportasi menuju kampus. Penelitian ini dilakukan secara kualitatif yang bersifat eksploratif menggunakan pendekatan grounded theory. Pengumpulan data dilakukan dengan kuesioner online dan sampling diambil menggunakan purposive sampling dimana sampel yang dipilih hanya yang dianggap tepat dan sesuai dengan kebutuhan penelitian. Data yang terkumpul kemudian dianalisis secara kualitatif menggunakan metode analisis isi. Hasil analisis menunjukkan terdapat delapan faktor utama yang mempengaruhi pemilihan sarana transportasi bagi mahasiswa yaitu kemudahan, efisiensi, hemat, preferensi individu, kenyamanan, kesehatan, keterbatasan kemampuan individu, serta sarana dan prasarana tidak memadai. Selain itu, berdasarkan hasil analisis korespondensi, mahasiswa ITB cenderung memilih angkutan umum, ojek/transportasi online, dan berjalan kaki untuk menuju kampus, sedangkan para mahasiswa UGM lebih cenderung menggunakan sepeda, sepeda motor, dan mobil. Temuan penelitian ini bermanfaat dalam memberikan informasi untuk penanganan keterbatasan sarana dan prasarana dalam kota serta untuk menurunkan tingkat kemacetan melalui pemerataan arus kendaraan
Penilaian Kondisi Bangunan Sekolah Menengah Pertama (SMP) di Kecamatan Ujan Mas, Kabupaten Kepahiang
Get PDFAbstractSchool buildings are an important tool to improve the quality of education, including junior secondary schools. Efforts to improve the quality of school buildings in Ujan Mas Subdistrict, Kepahiang Regency require identification of the physical condition of school buildings. The research conducted aims to identify the condition of the building, assess the level of damage and percentage of damage to the building elements of Junior High School buildings located in Ujan Mas District, Kepahiang Regency. The method used in this research is the weighting method by analyzing the level of damage to the building elements of the Junior High School building. The results showed that the damage condition at SMP N 1 Ujan Mas was 44.57% in the category of severe damage, SMP N 2 Ujan Mas was 42.11% in the category of moderate damage and SMP N 3 Ujan Mas was 30.07% in the category of moderate damage.Abstrak Bangunan gedung sekolah adalah sarana penting untuk meningkatkan kualitas pendidikan, termasuk Sekolah Menengah Pertama (SMP). Upaya meningkatkan kualitas bangunan gedung sekolah di Kecamatan Ujan Mas, Kabupaten Kepahiang diperlukan identifikasi kondisi fisik terhadap bangunan gedung sekolah. Penelitian yang dilakukan bertujuan untuk mengidentifikasi kondisi bangunan, menilai tingkat kerusakan dan mempresentasekan kerusakan pada elemen bangunan gedung Sekolah Menengah Pertama (SMP) yang berada di Kecamatan Ujan Mas, Kabupaten Kepahiang. Metode yang digunakan pada penelitian ini adalah metode pembobotan dengan menganalisis tingkat kerusakan pada elemen bangunan gedung Sekolah Menengah Pertama (SMP). Hasil penelitian menunjukkan bahwa kondisi kerusakan pada SMP N 1 Ujan Mas sebesar 44,57% kategori rusak berat, SMP N 2 Ujan Mas sebesar 42,11% kategori rusak sedang dan SMP N 3 Ujan Mas sebesar 30,07% kategori rusak sedang
Evaluasi Performa Teknologi Isolasi Dasar Tipe HDRB Pada Gedung Tidak Beraturan di Kawasan Gempa Tinggi
Get PDFEarthquakes frequently occur in Indonesia, including in Cemagi, Bali, which has a high seismic activity level (PGA: 0.4275 g). This study aims to evaluate the performance of the High Damping Rubber Bearing (HDRB) base isolation technology in an apartment building in Cemagi, Bali, with a complex design and irregular concrete structure. The building consists of 1 basement floor and 5 apartment floors with varying floor heights. The structural performance evaluation is conducted based on ATC-40 guidelines and SNI 1727:2020, SNI 2847:2019, SNI 1729:2020, SNI 1726:2019 regulations. This research investigates the application of HDRB through pushover and time history analysis, considering various design factors and local seismic conditions. The results show that the use of HDRB with a diameter of 1 meter on exterior columns and 0.8 meters on interior columns reduces displacement by up to 63.55%
Topic Modelling of Merdeka Belajar Kampus Merdeka Policy Using Latent Dirichlet Allocation
Get PDFTopic modeling is the process of representing the topics discussed in text documents. In the current era of internet technology development, digital data is growing increasingly large, including tweet data from Twitter. This research aims to obtain topic modeling related to the Merdeka Belajar Kampus Merdeka policy on Twitter, which has been classified into positive and negative sentiments. The topic modeling method used is Latent Dirichlet Allocation (LDA). This method is for summarizing, clustering, connecting, or processing data from a list of topics. The data used in this research are tweets with the keyword "Kampus Merdeka" uploaded on Twitter. A total of 1579 tweets with these keywords were classified into 648 tweets and 931 tweets, respectively, with positive and negative sentiments. Each tweet with positive and negative sentiment produces 5 topics with parameter values α and β of 0.1. The coherence value in topic modeling for tweets with a positive sentiment (0.44) is more significant than for tweets with a negative sentiment (0.38) and represent for drawing conclusions about topics based on relationship between keywords in negative sentiment is more challenging compared to those in positive sentiment to the Merdeka Belajar Kampus Merdeka policy on Twitter
Pengendalian Penyelesaian Proyek Berbasis Kinerja Menggunakan Hybrid Earned Value - Crash Program
Get PDFProject performance is an essential reference in supporting the success of construction implementation so that costs and completion time are according to plan. Previous research states that projects that experience delays will impact cost overruns which can be detrimental to contractors and project owners. This study takes the case of a performance evaluation on a building construction project that experienced a delay of 15.496% (25th week). The performance measurement results using the earned value, the project has an SPI value = 0.493, meaning that the project experienced significant delays. If the project is not controlled, it will take 72 weeks to complete from the 48-week plan at the cost of Rp. 64.57 billion from Rp. 57.23 billion. Control of this project needs acceleration which was carried out using the Crash Program method in 2 ways: (i) increasing the number of workers and (ii) maintaining the number of existing workers but increasing overtime hours. A practical solution alternative is to increase the number of workers, which results in a project completion time of 43 weeks with a final project cost of IDR 58.89 billio
The Effect of Using Glucomannan Flour and Carageenan on The Manufacture of Jelly Candy
Get PDFIndonesia is one of the countries that produces porang tubers in the world The biggest benefit of cultivating porang plants is to obtain the tubers. The harvested porang tubers can be sliced or chipped and then dried. Porang slices or chips can then be processed into konjac flour or konyaku. From konjac flour, glucomannan can be obtained. The aim of this research is to make jelly candy from porang flour which will be purified first by an extraction process using ethanol. The research method used was to extract 70 g of porang flour using foodgrade ethanol with a concentration of 50% as much as 560 ml by stirring on a hotplate at 30 ℃, stirring speed of 600 rpm and stirring time ( 30 minutes, 60 minutes, 90 minutes) which will then be filtered to obtain porang flour precipitate then in the oven for 12 hours with a temperature of 90 ℃. From the research results, it was found that the best glucomannan content was at a stirring speed of 600 rpm for 60 minutes, namely 81,52 %. Then, the best results of glucomannan flour were applied by being used as an ingredient for making jelly candy added to carrageenan
Annex IV Marine Pollution (MARPOL) Application for Pollution Prevention on Ketapang-Gilimanuk Route Crossing Vessels with Analytical Hierarchy Process (AHP) Method
Get PDFThe Application of the Marine Pollution (MARPOL) Annex IV regulation concerning sewage discharge from ferry ships operating on the Ketapang-Gilimanuk route plays a crucial role in pollution prevention. However, this essential role has been compromised due to suspicions that sewage waste from the Ketapang-Gilimanuk ferry ships is being directly discharged into the sea. Additionally, it is believed that the lack of sewage storage facilities at the port and inadequate supervision by local port authorities contribute to this issue. This research aims to investigate the implementation of MARPOL Annex IV in pollution prevention on ferry ships along the Ketapang – Gilimanuk route using the Analytical Hierarchy Process (AHP) method. This method is employed to establish a comprehensive evaluation framework by considering criteria such as safety management systems, safety and environmental protection policies, Company responsibilities and authorities, cultural and behavioral aspects, organizational factors, and technical considerations. Data will be collected through surveys and interviews with ship operators and members. Economical is more priority than operational techniques because it is related to capital expenditure and operational costs of each alternative to prevent marine pollution. Operational techniques are more priority than safety and environment because they are related to the technical and operational of each alternative to preventing marine pollution. Regulations are more priority than safety and environment because regulations affect each alternative, both Indonesian regulations and also SOPs at ports.
Performance Changes in Mass and Compressive Strength of High-Calcium Fly Ash Based Geopolymer Concrete Due to Sodium Sulphate Exposure
Get PDFThe sulfate environment is one of the conditions that significantly affect the durability of concrete. Sulfate attack causes cracks and affects the quality of the concrete. Therefore, it is necessary to innovate concrete that can withstand the aggression of this sulfate attack. Geopolymer concrete is a breakthrough that can be developed as an alternative material without using Portland cement as the ingredients, yet by using class F fly ash as the primary source material. On the other hand, the availability of class C fly ash with high CaO content is highly abundant in Indonesia. The high calcium content in this fly ash will cause the fresh geopolymer concrete to harden rapidly. Previous studies used sucrose as an additive to overcome this rapid hardening problem. However, its effect on the geopolymer concrete exposed to sulfate ingression requires further investigation. In this study, the geopolymer concrete was produced by using class C fly ash and sucrose. The sulfate ingression was simulated by immersing the concrete specimen in the sodium sulfate solution while the mass changes and compressive strength were examined. pH measurement of the sodium sulfate solution was also carried out to provide a different perspective on the data analysis. Cylindrical specimens, measuring 10 cm x 20 cm, were produced using the dry-mixing method and the characteristic strength of 28 MPa according to SNI 2847–2019. From the results, geopolymer concrete with sucrose showed a high workability performance through the high slump value obtained. Nevertheless, the experimental results also indicated the declining strength of geopolymer concrete after the sulfate exposure. However, only a slight reduction was observed. The strength residue still satisfies the minimum requirement of SNI 2847-2019. It shows the potential of geopolymer concrete to be used as a construction material in a harsh environment with high sulfate content