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Development of Marine Loading and Unloading System for Ro-Ro Vessel
Get PDFShip stability is one of the important criteria for ship safety as required by IMO and Indonesia Classification Bureau (BKI) in various rules. One of it is the IMO code of Intact Stability. Many factors affect the stability of a ship, including ship load, which in application varies in weight and type of vehicle. Maxsurf has been used to analyze various conditions of the ship, including stability. However, Maxsurf is too complicated to be used by ordinary people. For that a package needed as mediator to Maxsurf to be easier to use. This research developed a package to assist in analyzing the ship stability with vary in weight and type of vehicle. The package was created in Microsoft Excel worksheet and is connected to Maxsurf Stability. Visual Basic for Application was use to write the codes (coding) for the package command. The target ship used in this analysis is a 500 GT ferry ship. After the package is working properly, the analysis simulation can be run. Simulation results show that maximum GZ of both fully loaded and overloaded conditions occur at tilt angle of around 30o. Exceeding such value, the ship for both conditions slowly lose the turning moment. At fully loaded condition, the ship hardly turns back after reaching a tilt angle of 73 o. At overload condition, the ship is still safe though losing its ability to turn back is faster, at heel angle of 71o
Synthesis N-Doped Activated Carbon from Sugarcane Bagasse for CO2 Adsorption
Get PDFNitrogen-doped activated carbon (SBACN) was synthesized from sugarcane bagasse waste as acarbon source and urea as nitrogen source through potassium hydroxide (KOH) activation for 2 h at high temperature via two step methods. The synthesized SBCN was characterized using X-Ray Diffraction (XRD), Scanning Electron Microscope (SEM), and Fourier Transform Infrared (FTIR). The results showed that the SBCN has low degree crystallinity and graphitization with highly developed micropores due to synergistik activation effect of KOH and urea. These characteristics provide an important contribution to carbon dioxide adsorption capacity, which can reach up to 11,20% wt and this value is higher than pristine activated carbon. The results indicating that the presence of this nitrogen functionalities is found to have a beneficial influence on the carbon dioxide adsorption characteristic in standart condition and exhibit considerable potential in solid adsorption
Intuition in Information Technology Investment Decision: A Quantitative Method
Get PDFIT investment decisions made by the company have uncertain value characteristics; have a high risk than other capital investment failures and intangible benefits of expected. In this situation, effective decision making is an important (perhaps most important) part of managerial activity. In this article, we analyze the influence of decision making under uncertainty, company size, and environmental hostility to intuition and analyze the intuition of company performance. There are five companies as study sample (ie: university, hospital, regional owned enterprises, creative industry, and software house industry) in East Java, Indonesia. The method used was a survey. The respondents were Top Level Management that is responsible for IT investment decision. Data analysis techniques used was Structural Equation Modeling-Generalize Structure Component Analysis (SEM-GSCA). Although intuition process is critical for effective IT investment decision making, we found that: (1) decision making under uncertainty and environmental hostility did not affect on intuition; (2) company size has a positive effect on intuition, and (3) intuition has a positive effect on company performanc
Interpretasi Batuan Bawah Permukaan Prospek Bijih Besi di Kawasan Desa Pagubugan dan Desa Pagubugan Kulon Kecamatan Binangun Kabupaten Cilacap Berdasarkan Survei Magnetik
Get PDFGeophysical exploration to determine the potential of iron sand in the Pagubugan Village and Pagubugan Kulon Village areas, District of Binangun, Regency of Cilacap has been carried out from May to August 2018 using the magnetic method. The acquisition of magnetic data has been done in the research area at the geographical position stretching from 109.2988° E to 109.31892° E and 7.68430° S to 7.70402° S. Morphologically, the research location is the part of the eastern coastal in the district of Binangun. The results of the modeling and interpretation of magnetic anomaly data that obtained indicate the presence of rock deposite which thought to contain iron ore which intersects with clay, silt, sand, gravel, and crust from the Alluvium formation with a magnetic susceptibility value of 0.0094 cgs units. This rock deposite is estimated to lie at a depth of 0 to 53 meters and stretches at the geographical position from 109.30981° E and 7.69264° S to 109.31787 °E and 7.69575° S
CONNECTION MODEL OF CONCRETE FILLED STEEL TUBE (CFT) COLUMN TO STEEL BEAM UNDER CYCLIC
Get PDFVarious types of structural technology began to develop rapidly, one of which was composite steel. Composite steel (Concrete Filled Steel Tube) is a structure consisting of two or more materials with different material properties and form one unit so as to produce better combined properties. Compared to conventional steel, this column has many advantages such as convenient formwork for concrete cores provided by steel tubes, increased strength and good ductility. This study uses the CFT column as the main variable by considering variations in the CFT column on the connection using ABAQUS. Modeling was carried out with a test object of 203 × 133 × 7.8 × 5.8 mm and the CFT column dimensions of rectangular 220 × 220 × 6 mm, and circular Ø 220 mm t = 8 mm. The research method uses two steps static-general method with static-risk. The results of these two research methods have the results of approaching and having the same behavior. Modeling has fulfilled the requirements of modeling the column-beam joints that can be used in a system of earthquake-resistant reinforced steel composite concrete frame structures. Based on the modeling results that have been done, modeling has fulfilled the connection that has sufficient ductility capability
Designing Passive Harmonic Filter on Dynamic Positioning Vessel's Electrical System Affected using Electrical Thruster
Get PDFShip with a dynamic positioning system has the ability to maintain her position dynamically. To be able to maintain the position, generally, ship with a dynamic positioning system have several thrusters located at bow or stern of the ship. Based on the propulsion system, there are 2 types of thruster which are mechanical thruster and electrical thruster. In electrical type, the thruster is driven by an electric motor supplied from the generator. In addition, on dynamic positioning vessel equipped with the electrical thruster, there are also VFD or Variable Frequency Drive to control the speed of motor thruster. The use of VFD components in the system may cause harmonic interference. Harmonic itself can be regarded as distortion in the sinusoidal waves due to the interference of other waves that have integer frequency multiples of their fundamental frequency due to the operation of non-linear thruster motor. Some of the most affected components of this distortion are the communications equipment and the components used for measurement. This research conducted an analysis of harmonic disturbance arising from the operation of 2 units bow thruster on DP Ship by simulating 6 scenarios of generator configuration using simulation software. The results from this research were total harmonic distortion value or VTHD of the system that complies with standards and rules, also the specification of a passive harmonic filter to reduce the VTHD value at the specific harmonic order
Modeling Coffee Price using Jump Diffusion Model: The case of Ethiopia
Get PDFEthiopian coffee price has significant effect on the economy of the country and its price is highly fluctuated. In this study, we aim at modeling and forecasting the washed Sidama class A grade 3 (WSDA3) coffee price in Ethiopia to reduce the risks associated with this price fluctuation. We used daily closed price data of Ethiopian WSDA3 coffee recorded in the period 31 May 2011 to 30 March 2018 obtained from Ethiopia commodity exchange (ECX) market to analyse the prices fluctuation. The nature of log-returns of the price is asymmetric (negatively skewed) and exhibits high kurtosis. We used a Jump diffusion model to model and forecast the empirical data. The method of maximum likelihood is used to estimate the parameters. We used the root mean square error (RMSE) to test the goodness of fitting for the model to the data. This test indicates that the model performs well
Kajian Strategi Aplikasi Material Kayu Bekas Pada Elemen Desain Interior Restoran di Bandung
Get PDFDesain Interior sangat berperan dalam menjaga keharmonisan antara manusia dan lingkungan melalui desain eko-interior. Karakteristik fisik dari desain eko-interior mudah ditemukan dalam aplikasi material ramah lingkungan seperti material kayu bekas yang digunakan kembali pada elemen interior. Beberapa restoran di Bandung telah menerapkan penggunaan kembali material kayu bekas dalam elemen interiornya. Penelitian ini bertujuan untuk mengidentifikasi strategi dan tingkat terapan penggunaan kembali material kayu bekas yang diterapkan oleh desainer sebagai elemen interior restoran. Metode penelitian yang digunakan adalah kualitatif-deskriptif. Hasil dari penelitian ini diukur dengan metode ukur DCBA menunjukkan bahwa tingkat terapan aplikasi material kayu bekas pada elemen interior restoran di Bandung masih dalam kategori “Terapan Umum” dan “Upaya Ringan” belum mencapai situasi ideal eko-interior