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Motion Response on The Water Ambulance Ship
Get PDFIn designing a ship, it is necessary to know the response of the ship's motion before sailing. The purpose of this research is to determine the ship's motion response to waves as well as ship speed in ship loading operational conditions. The method used in this study is the B-spiline mathematical equation and the strip theory method, with the help of ship motion software, which varies the ship's load by 100% DWT, 50% DWT, and 25% DWT. While the highest significant amplitude heave value occurs on a ship with 100% DWT conditions with a speed of 18 knots and a wave direction of 900, which is 2.70 meters, the highest significant value of amplitude pitch occurs on a ship with a condition of 25% DWT with a speed of 6 knots and a wave arrival direction of 1800, namely 1.10 degrees, and the highest significant value of roll amplitude occurs in ships with 25% DWT conditions with speeds of 18 knots with a wave arrival direction of 900, which is 3.42 deg. The research results detected at a speed of 18 knots for the significant amplitude heave value, the significant amplitude pitch value, and the maximum RAO value still meet the Nordforsk criteria
Tinjauan Molekular Proses Loading dan Unloading Rifampicin pada Etil Selulosa dan (Etil selulosa)-g-(Poly-Dimethylaminoethyl Acrylate)
No full textTuberkulosis merupakan penyakit menular dengan jumlah kematian 34 orang per 100.000 penduduk. Oleh karena itu,penelitian mengenai pengobatan tuberkulosis menjadi penting dari segi penghantaran obat maupun efektivitas obat. Kopolimer etil selulosa-g-(poly-dimethylaminoethylacrylate) atau EC-g-PDMAEA mempunyai potensi sebagai pembawa obat karena dapat membentuk misel yang sesuai untuk jenis obat hidrofobik yaitu rifampicin. Pemahaman perilaku molekular dan interaksi EC-g-PDMAEA terhadap rifampicin menjadi bagian yang penting dalam sintesis dan aplikasi kopolimer dari etil selulosa ke depannya. Berdasarkan simulasi dinamika molekul menggunakan GROMACS 2020.6, EC-g-PDMAEA menghasilkan pola loading rifampicin yang mirip dengan pola loading dari etil selulosa (EC). Pola unloading dari EC-g-PDMAEA menunjukkan tren data yang lebih baik dibandingkan dengan EC dari segi pergeseran puncak Radial Distribution Function yang diamati untuk rifampicin dari jarak 0,86 menuju 0,96 nm.
Daya Dukung Model Kelompok Tiang dan Block Foundation Dengan Variasi Panjang dan Spasi Tiang
No full textAnalysis of bearing capacity for foundation design is important. Therefore, need an alternative design to know actual capacity of pile group and block. Models of pile group with variations in number, length, and spacing is used on uniform loose sand for proved it. The loading tests conducted on pile models and record p-y curve. The research aims to study effect of number, length, spacing of pile in piles group compared with pile capacity of block. Based on 25 mm settlement of loading test, the result shows block foundation, 3d and 5d spacing has capacity 1560N, 1200N, 1230N respectively on 400 mm length. Analysis of p-y curve with Chin methods, pile capacity of spacing 5d, 3d of pile group and block, in sequence, were 1380N, 1430N and 1660N. Hence, its can be concluded that the pile group in 3d spaced has a larger capacity than 5D spaced
Evaluating the Fitting Performance of AGARCH(1,1), NAGARCH(1,1), and VGARCH(1,1) Models
Get PDFThis study compares the performance of the GARCH(1,1), AGARCH(1,1), NAGARCH(1,1), and VGARCH(1,1) models fitted to real data. The observed real data are the USD exchange rate against IDR in the daily period from January 2010 to December 2017. To identify the superiority and evaluate the performance of those models in capturing the heavy-tailed and skewed character in exchange rate distribution, the return error is assumed to be the Normal, Skew Normal (SN), Skew Curved Normal (SCN), and Student-t distributions. The model's parameters are estimated using the GRG Non-Linear method in Excel Solver and the ARWM method in the MCMC scheme implemented in the Scilab program. Estimation results using Excel's Solver have similar values to the estimates obtained using MCMC, concluding that Excel's Solver has a good ability in estimating the model's parameters. Based on AIC values, this study concludes that the NAGARCH(1,1) model under Student-t distribution performs the best
Bivariate Archimedean Copulas to Solve Complex Dependency in Marine Engineering Problems
Get PDFClimate change has made offshore installations suffer severe consequences from extreme marine hazards. These offshore installations were designed to withstand extreme natural hazards. Marine natural hazards commonly occur interdependently. Thus, a multivariate model to capture this complex dependence structure is necessary. Practically, modelling marine natural hazards is usually assumed to be mutually independent or correlated by a multivariate Gaussian distribution. However, this biased assumption is not relevant to capture the real dependence structure between marine parameters. Copula functions are used to model the complex dependence structure between marine parameters. A simplified case study is selected to illustrate the modelling between wave height and wind speed. Results are compared with the traditional joint probability approach to demonstrate the advantage of copula functions. The use of copula functions provides a better result to model any complex dependence structure between correlated variables
Local Analysis of The Padeye-Brace Clamp Structure Strength during Installation of Riser-Spool at Offshore Platform
Get PDFThe need for natural gas in Indonesia has developed very rapidly, thus encouraging the construction of many production support facilities. One of them is the Wellhead Platform B (WHP-B) in West Pangkah waters, East Java. This production platform is in shallow water conditions with a depth of less than 5 m and a distance of less than 5 km from the shoreline. Therefore, when the pipe installation process is carried out, a crane barge or construction vessel type cannot be used. To be able to connect the gas flow from the well to the production platform (WHP-B), it requires a supporting structure in the form of a spool and riser. The size of the spool and riser that will be installed on WHP-B is 16” and 6” with the condition that the riser and spool are connected. A crawler crane carried by a barge can be used for the installation process to occur efficiently. For the 16”-6” riserspool to be lowered simultaneously, it requires a temporary structure that serves to clamp the two pipes so that they can be installed simultaneously. This structure is a modification between the padeye and the brace clamp. The process of lowering the 16”- 6” riser-spool experienced a critical condition when it was in the splash zone. Based on the global analysis results, it is known that the UC that occurs is 0.97 with a vertical bending stress of 172.36 MPa in the 3rd padeye-brace clamp structure. After conducting local analysis on the 3rd brace clamp, it is known that the clamp structure is still in a safe condition with a maximum von Mises stress of 2.42 MPa and a maximum deformation of 0.0096 cm
UI/UX Analysis on the Geek Studio Website Using the User Centered Design and User Experience Questionnaire (UEQ) Method
Get PDFGEEK STUDIO engaged in photography such as photo studios and rental shooting tools. Based on the results of an interview with the owner of GEEK STUDIO, there is a problem to develop a website profile system that cannot be used optimally because the existing website is still considered less than optimal in terms of user experience (UX) and user interface (UI) so it is less attractive and less comfortable to use. therefore, the researcher will analyze the website which according to the source is still the maximum turning using the UCD and UEQ methods. User-Centered Design (UCD) is one of several design methods where the method is focused on the needs and preferences of its users. UCD is a process that is carried out repeatedly where the design and evaluation are developed from the initial stage to the implementation periodically. Then the User Experience Questionnaire (UEQ) is a method in the form of a questionnaire where the method serves to measure the viewing experience of users of a product. The most basic goal of UEQ is to quickly calculate its user experience through questionnaires. Based on research data that has been carried out by the author, a conclusion can be drawn where the results of the study have produced previous design benchmark values, namely attractiveness 1.11, perspicuity 1.16, efficiency 1.41, dependability 1.31, stimulation -0.76 and novelty -0.96 While in the design afterward, namely attractiveness 2.49, perspicuity 2.20, efficiency 2,26, dependability 2.00, stimulation 2.05 and novelty 2.18, Based on this, it can be seen the improvement of the chart from the benchmark which was originally from bad to above average to excellent overall
Food Carrying Capacity in Gerbangkertosusila Metropolitan Area Using Ecosystem Service-Based Carrying Capacity
Get PDFThe issue of food security in Indonesia will persist due to the availability of agricultural area and problems surrounding it. Agricultural land conversion, urbanization-led urban expansion, endogenous and exogenous growth of the region with its population also helps intensify the issue of food security. Gerbangkertosusila metropolitan area is the largest urban agglomeration in East Java Province. Compared to other area in East Java, it has a relatively rapid increase in growth. This causes the quality and quantity of the environment to decrease. Efforts to support the sustainability of an area to meet the needs of humans and other living things require the carrying capacity and capacity of the environment. Therefore, it is necessary to analyze the status of food carrying capacity based on the environmental service. This research uses the modified environmental service-based carrying capacity with spatially calculated dynamic, as opposed to the administrative-based calculation that the common measurement has. The spatial dynamics in a region are captured with the grid-system, with other variables also follows the same grid. The result shows that mostly over 89% of the regions’ (represented in grids) food carrying capacity has already been overshot, and that all of the population threshold has also been overshot with exception in Lamongan Regency. It shows that Gerbangkertosusila metropolitan area is currently in a critical situation where it couldn’t support the food security by itself and that it needs to rely on other region forming a larger regional system to maintain its sustainability
Dewan Redaksi
Get PDFPuji syukur kami sampaikan kepadaNya. Kini tiba saatnya untuk menerbitkan JMAIF 7 (1) Januari 2023. Edisi JMAIF 7 (1) Januari 2023 berisikan mengenai kajian aset infrastruktur mengenai aset bangunan, pasar, properti dan jalan dalam pengembangan riset infrastruktur.Edisi, JMAIF 7 (1) Januari 2023 terbit terlambat. Keterlambatan ini harus diperbaiki untuk Edisi selanjutnya