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Effect of Preheating Process and V Groove Type on the Tensile and Metallography Test of ASTM A53 with A36 Weld Joint Using FCAW Method
Get PDFSteel is a metal material that is often used in the maritime industry due to its availability and weldability. ASTM A53 steel is a low carbon steel commonly used for piping applications. ASTM A36 steel is a low carbon steel commonly used for offshore buildings. This study aims to determine the influence of preheat temperature and V groove type on bend resistance of A53 and A36 weld joint using FCAW (Flux Cored Arc Welding) method. The preheat temperature used are 100°C and 150°C with groove type variations used were single V groove and double V groove. The type of protective gas used is 100% CO2. The results of tensile strength test showed that in the welding process in this study, specimen with preheat temperature of 150°C and double V-Groove shape has the strongest tensile strength, with HAZ width of 3.91 mm, ferrite phase percentage of 58.08%, and pearlite phase percentage of 41.92%
Sensitivity Analysis to Determine the Prospect of Tollroad Investment: Case Study Krian-Legundi-Bunder-Manyar Tollroad
Get PDFPT Waskita Bumi Wira as the Toll Road Business Entity (BUJT) is investing in the Krian-Legundi-Bunder-Manyar Toll road with a viability gap fund (VGF) scheme. In the 2016 Toll Road Concession Agreement (PPJT) between BPJT-BUJT-PII, several acceptable investment variables have been agreed, namely: total investment value = Rp12,224,389,000,000, average daily traffic volume (LHR) = 21,874 vehicle / day, loan interest = 12.5%, toll tariff for group 1 = Rp1,250 / km, internal rate of return on equity (IRRonEquity) = 17.64%, payback period of 14 years and net present value (NPV) = Rp. 3,731,695,000,000. During the construction, there was a design change and a delay in land acquisition, this causes cost overrun. With a concession period of 45 years, inaccurate risk factors in the prediction of traffic volume growth rates, specific and non-specific risk factors and other uncertainties greatly affect the investment prospects. Therefore investment needs to be reviewed before this toll road is divested in 2025 by sharpening the minimum attractive rate of return (MARR) and LHR variables, then comparing them with the initial business plan. The estimated selling price of the divestment is also examined in this study. The investment valuation criteria that will be used in the sensitivity analysis are NPV and IRRonEquity. The approach in determining MARR is the use of MARRpremium = 15.81%. Sensitivity analysis with a deterministic approach is carried out to obtain limits on changes in investment costs, land acquisition costs, LHR traffic, loans (syndicated loans) to NPV in several tariff scenarios. This research shows that the NPV value is very sensitive to changes in investment costs. It is also known that in the toll tariff scenario according to PPJT compensation can be given in one of the conditions: investment costs increase by more than 7%, LHR traffic is less than 75%, or an increase in loans (syndicated loans) of more than 9%. The analysis of the stochastic approach shows that the probability of not exceeding the investment budget revenue limits due to changes of 37.29% to 46.56%
Fluid Flow Analysis of Stern Hull MV. Kelola Mina Makmur 150 GT Based Engine Propeller and Hull Matching Using Actuator Disk Propeller Method
Get PDFThe results of the simulation used a propeller disk actuator method that models the propeller effect without modeling a real propeller. Direct optimization will be calculated using the CFD method of each variation of the clearance propeller configuration indicating that the amount of propulsion efficiency produced is very dependent on the clearance propeller. The most optimal propulsion efficiency occurs at a distance of 0.738 m from the steering shaft with a Dprop = 0.88, KT = 0.22, KQ = 0.028, and J = 0.40 besides having an advance velocity visualized with a Va = 10.6 knots which has a 50% propulsion efficiency, which the value will decrease according to the reduction in distance propeller. The less efficiency of the propulsion produced in the clearance propeller between -0.162 - 0.438 m from the steering shaft. This is because the slope angle between the entry of water and the longitudinal axis of the ship's hull on the stern exceeds the required conditions
Optimasi Sumber Daya Air Di Sub DAS Air Betung, Kota Pagar Alam Sumatera Selatan
Get PDFSaat ini, keseimbangan air di Sub DAS Air Betung mengalami penurunan kualitas dan kuantitas sebagai akibat dari perkembangan wilayah perkotaan dan peningkatan kegiatan ekonomi. Dari kondisi tersebut, sangat penting untuk dialokasikan secara efisien agar konflik kepentingan terhadap air dapat dihindari. Tujuan penelitian adalah mengoptimalkan SDA untuk memenuhi kebutuhan udara rumah tangga, industri, dan irigasi. Metode analisis menggunakan aplikasi program linier. Hasil SDA tahun 2019 dan 2028 diperoleh nilai maksimal Rp 19.721.880 dan Rp 22.621.050. Alokasi air untuk memenuhi kebutuhan air rumah tangga dan industri dipasok dari air permukaan.Selanjutnya, alokasi air untuk pemenuhan kebutuhan air irigasi disediakan dari air permukaan dengan debit mata air lainnya
Explainable Artificial Intelligence (XAI) towards Model Personality in NLP task
Get PDFIn recent years, the development of Deep Learning in the field of Natural Language Processing, especially in sentiment analysis, has achieved significant progress and success. It is because of the availability of large amounts of text data and the ability of deep learning techniques to produce sophisticated predictive results from various data features. However, the sophisticated predictions that are not accompanied by sufficient information on what is happening in the model will be a major setback. Therefore, the significant development of the Deep Learning model must be accompanied by the development of the XAI method, which helps provide information about what drives the model to get predictable results. Simple Bidirectional LSTM and complex Bi-GRU-LSTM-CNN model for Sentiment Analysis were proposed in the present research. Both models were analyzed further using three different XAI methods (LIME, SHAP, and Anchor) in which they were used and compared to two proposed models, proving that XAI is not limited to giving information about what happens in the model but can also help us to understand and distinguish models’ personality and behaviour
Kendali Optimal Penyebaran Penyakit Influenza H1N1 Tiga Strain dengan Vaksinasi dan Pengobatan
Get PDFH1N1 influenza is a respiratory tract infection with common symptoms, namely fever, headache, coughing, and sore throat. H1N1 influenza has several strains known to infect humans, birds, and pigs. Some efforts to overcome the infection of the H1N1 influenza virus are vaccination and treatment. This Research discusses the optimal control in the form of vaccination and treatment applied to the model H1N1 Influenza disease spread. The method used to solve this optimal control problem is the Pontryagin Minimum Principle followed by searching numerical solutions using the Runge-Kutta Forward-Backward Sweep method. Numerical simulations were conducted to compare the spread of H1N1 Influenza before and after optimal control efforts were given. Based on the simulation result, it was shown that giving optimal control in the form of vaccination to susceptible individuals and treatment in individuals infected with three strains could reduce the number of individuals infected with H1N1 Influenza disease
Analisis Kapasitas Struktur Atas Jembatan Mahakam IV (Tipe Arch Bridge) Kalimantan Timur
Get PDFThe construction of Mahakam IV bridge is motivated by the problem of vehicle traffic congestion that occurs in the Mahakam I Bridge area. This study aims to determine the forces that occur, and also find out the safety profile used. The research method was started by modeling the Mahakam IV Bridge in the Midas Civil program, and than calculated loadingstandar use SNI 1725-2016 and then calculated according to the RSNI T-03-2005 standard. After that, an analysis is carried out on the Midas Civil program to get the results in the form of axial force, shear force and moment. The results of the Midas civil program are the largest axial force value of 1583394 kg, the shear force of 8547.18 kg, and the moment of 14070.61 kg.m. From the results of this analysis, it can be concluded that the girders are elongated, transverse girders, and the mainframe is safe
The Impact of Folding Shutter on the Daylighting Performance in Tropical Climate
Get PDFUtilization of abundant sunlight in tropical climates as daylighting can help to save energy consumption in the flats building. Based on daylight conditions in tropics, there is a need for a dynamic shading to be applied in façade which can be transformed to respond to the environmental change. Folding shutter is a dynamic shading device which can be operated by using folding and rotation motion. This paper aims to discuss the impact of folding shutter on the daylight performance in the context of flats buildings in tropical climates. Simulation using Radiance was conducted to test the sub-variables of folding shutter, including the folding configurations and shutter’s rotation angles on different conditions in tropics. The results showed that folding configurations results in high increase of daylight intensity and should be applied moderately. Meanwhile the shutter’s slats can help to diffuse and reflecting incoming light to the deepest areas of room. A closed configuration with shutter’s angle of 0° and 45° performed the best to face the inconsistent cloud movement in partly cloudy sky. The integration of folding shutter and 60 cm overhang produced the most stable performance which can meet the visual comfort standard in the longest period in tropics
Analisis Perilaku Vertical Eccentrically Braced Frame Menggunakan Profil Tubular Ganda
Get PDFSistem struktur Eccentrically Braced Frame (EBF) membatasi perilaku inelastis pada link balok yang terletak di antara dua bracing eksentris. Link geser tubular memiliki daktilitas yang lebih baik dari link geser WF. Hal ini menunjukkan bahwa link tubular lebih stabil menahan beban siklik. Dalam penelitian ini, dilakukan evaluasi perilaku sistem rangka bresing eksentrik vertikal 10 lantai menggunakan aplikasi SAP 2000 dan permodelan validasi numerik berdasarkan jurnal Rahnavard dengan analisis beban siklik menggunakan Abaqus. Permodelan SAP 2000 menunjukkan bahwa penggunaan kolom King Cross, balok dan bracing menggunakan Wide Flange, link SHS tubular ganda dengan panjang link vertikal 400 mm dan jarak antar link vertikal 800 mm telah sesuai dengan kontrol desain. Permodelan validasi dan jurnal menghasilkan gaya geser masing-masing sebesar 389,9 kN dan 400 kN dengan selisih 2,75%
Perubahan Pola Pergerakan Orang Ke Tempat Ibadah Selama Masa Pandemi Covid19 (Studi Kasus Mesjid Raya Baiturrahman Kota Banda Aceh)
No full textKota Banda Aceh merupakan kota wisata islami dengan kebiasaan masyarakat melakukan shalat berjamaah di masjid. Penyebaran wabah Covid-19 mengubah hak kebebasan beragama menjadi pembatasan kegiatan keagamaan. Pembatasan ini dimaksudkan agar masjid tidak menjadi media penyebaran Covid-19. Kajian ini bertujuan untuk mengobservasi pola pergerakan orang ke tempat ibadah dengan menggunakan data penggunaan lahan parkir. Lokasi kajian di Mesjid Raya Baiturahman Banda Aceh yang merupakan pusat ibadah masyarakat muslim di Aceh sekaligus landmark kota yang dijadikan destinasi wisata oleh turis maupun penduduk lokal. Hasil kajian menunjukkan bahwa penerapan pembatasan sosial mempengaruhi pola pergerakan masyarakat. Pembatasan sosial menyebabkan jumlah pergerakan menurun ≥ 50% pada hari Jumat dan Minggu. Sedangkan pada hari kerja menunjukkan kenaikan, namun tidak sebesar nilai penuruan pada hari Jumat dan Minggu. Nilai determinasi dan korelasi menunjukkan karakteristik hari berkorelasi positif dengan jumlah pergerakan masyarakat menuju mesjid. Jumlah pergerakan ini dapat dijelaskan oleh variabel karakteristik hari