scholarly journals Comparison of Predicted Obstacle Prediction for ALPO Type Catamaran Transport Vehicle

2019 ◽  
Vol 4 (2) ◽  
pp. 149-157
Author(s):  
Wibowo Harso Nugroho ◽  
Abdul Kadir ◽  
Nanang JH Purnomo ◽  
M. Syaiful ◽  
Ahmad Yasim

With the increase of the Decommisioning Offshore Platform in Indonesia water, a decommisioning vehicle is needed to dismantle and transport the offshore platform. Because of the operation of this vehicle to disassemble offshore platform in various offshore platform locations in Indonesian water, it is necessary to consider the vehicle main engine power by predicting the ship resistance when traveling to the offshore platform location. This paper discusses the results of several numerical prediction methods of resistance that applied on the catamaran ship type. The prediction method used for resistance calculation which based on satistical data and analytical methods from the cylindrical body theory. The resistance prediction on the decommisioning vehicles using maxsurf resistance with various methods at 12 knots service speed shows that Holtrop method produces a resistance value of 250.7 kN, the Van Oortmerssen method produces a resistance value of 955 kN, the Series60 method produces a resistance value of 210.5 kN, the Compton method produces a resistance value of 295.8 kN, the Fung method produces a resistance value of 540.6 kN, method Slender body produces a resistance value of 7036.4 kN, the Wyman method produces a resistance value of 603.2 kN and finally the last method of KR Barge produces a resistance value of 1258.5 kN. This study show that the differences of the result are significant from each of the prediction methods so that testing of the hydrodynamic model is highly recommended.

1993 ◽  
Vol 30 (04) ◽  
pp. 297-307
Author(s):  
John M. Almeter

There are literally dozens of different ways that the boat designer can predict the resistance of planing hulls. The term planing hull is used generically to describe the majority of hard chine boats being built today. No single prediction method is good for all types of planing hulls. Some methods can be relied on to give good predictions for certain boats and other methods can't be relied upon at all. This paper is meant as a reference for designers in selecting resistance prediction methods for planing hulls. It describes numerous resistance prediction methods and gives their variable ranges and the type of planing hulls they are based on or are intended for. Inherent problems or limitations of the methods are stated. The concept of hull shape, which is often neglected in resistance prediction, and its important role are discussed.


Teknomekanik ◽  
2020 ◽  
Vol 3 (1) ◽  
pp. 17-21
Author(s):  
Salmat Salmat ◽  
Arya Zulhendrik ◽  
Muhammad Iqbal Iski ◽  
Arifin Adli ◽  
Aulia Zulkanain Nasty

The Nastional Unmanned Fast Boat Contest 2019 is an event to discover colleger interests and talents about ships and as an event to hone and develop college competitions.B-NINE TEAM from Universitas Negeri Padang is very interested and interested to participating based on illegal fishing problem that occurs. Ship design through literature study and ship model analysis using computer simulations. Ship comparison methods and trial-error to determine the shape of the hull to be userd and numerical experiments.Dimensions of the ship are Length Overall 0.80 m; Length Waterline 0.79 m; Beam 0.05 m; Depth 0.24 m; Draft  0.05 m. The variable parameter used is the variation of catamaran hull type V asymmetric inner flat. There are two types of modification applied, that is modification hull type U asymmetric and modification hull type U symmetric. Based on result of computer simulation testing, based on result of computer simulation testing, it is found that modification hull type U asymmetric has a low resistance value is 5.31 N at a speed of 4.2 knots with effective is 0.04776 Kw and main engine power of 0.1.70 KW.


2020 ◽  
Vol 8 (1) ◽  
pp. 42
Author(s):  
Firyal Baktir ◽  
Dwi Prijatmoko ◽  
Masniari Novita

There are several methods of analizing tooth size discrepancy in orthodontics include prediction methods for mixed dentition. Prediction method of Moyers and Sitepu most commonly used although both were obtained from 2 different races, Caucasian and Deutromelayu. Yemeni ethnic is one of the ethnic groups settled in Indonesia which descendants of the Caucasian race. The aim of the study was to observed the suitable prediction table for Yemeni ethnic. It was an observasional analitics study consist of 40 samples with cross sectional design. The results showed that slight difference for prediction of Moyers on the maxilla (1.02) and prediction of Sitepu on the mandibula (0.11). As conclusion, the most suitable predicition method for Yemeni ethnic is Moyers’s method for maxila and sitepu’s method for mandibula.   Key words: mesiodistal width permanen teeth, Moyers method, Sitepu method, Yemeni Etnic


Author(s):  
John W Chew ◽  
Feng Gao ◽  
Donato M Palermo

This paper presents a review of research on turbine rim sealing with emphasis placed on the underlying flow physics and modelling capability. Rim seal flows play a crucial role in controlling engine disc temperatures but represent a loss from the main engine power cycle and are associated with spoiling losses in the turbine. Elementary models that rely on empirical validation and are currently used in design do not account for some of the known flow mechanisms, and prediction of sealing performance with computational fluid dynamics has proved challenging. Computational fluid dynamics and experimental studies have indicated important unsteady flow effects that explain some of the differences identified in comparing predicted and measure sealing effectiveness. This review reveals some consistency of investigations across a range of configurations, with inertial waves in the rotating flow apparently interacting with other flow mechanisms which include vane, blade and seal flow interactions; disc pumping and cavity flows; shear layer and other instabilities; and turbulent mixing.


2021 ◽  
Vol 16 ◽  
Author(s):  
Yayan Zhang ◽  
Guihua Duan ◽  
Cheng Yan ◽  
Haolun Yi ◽  
Fang-Xiang Wu ◽  
...  

Background: Increasing evidence has indicated that miRNA-disease association prediction plays a critical role in the study of clinical drugs. Researchers have proposed many computational models for miRNA-disease prediction. However, there is no unified platform to compare and analyze the pros and cons or share the code and data of these models. Objective: In this study, we develop an easy-to-use platform (MDAPlatform) to construct and assess miRNA-disease association prediction method. Methods: MDAPlatform integrates the relevant data of miRNA, disease and miRNA-disease associations that are used in previous miRNA-disease association prediction studies. Based on the componentized model, it develops differet components of previous computational methods. Results: Users can conduct cross validation experiments and compare their methods with other methods, and the visualized comparison results are also provided. Conclusion: Based on the componentized model, MDAPlatform provides easy-to-operate interfaces to construct the miRNA-disease association method, which is beneficial to develop new miRNA-disease association prediction methods in the future.


2020 ◽  
Vol 10 (6) ◽  
pp. 1942
Author(s):  
You Xianhui ◽  
Wu Zhaoqi ◽  
Chen Zehao

Grouted connections are commonly used in marine engineering, especially on oil platforms, cross-sea bridges, and offshore wind power turbines. The prediction methods for axial carrying capacity of grouted connections with shear keys and their application ranges in current codes were analyzed in this paper. The calculated results by using different codes were compared based on a practical grouted connection between steel piles and the jacket foundation of a wind turbine. The research team conducted axial compression tests on seven specimens, collected a wide range of experimental results to establish a database, and finally compared the standard calculation results with the experimental results. The study indicates that the axial strength of grouted connections predicted by different methods is distinct. The calculation formula of the British Health and Safety Executive (HSE, 2002) has obvious limitations; specifically, with increased shear keys, strength is overestimated, resulting in insecure design outcome of structures. The results calculated by the Norwegian Det Norske Veritas (DNV, 2013) are generally consistent with the experimental results, in which the reduction effect of multiple shear keys was considered. The prediction method of the American Petroleum Institute (API, 2007), which undervalues the bearing performance of connections, is excessively conservative. The method of the combined Norwegian and German Det Norske Veritas–Germanischer Lloyd (DNV-GL, 2016) has wider applicability and is safe, reliable, and economical.


2020 ◽  
pp. 0309524X2094120 ◽  
Author(s):  
Zhongda Tian

With the continuous growth of wind power access capacity, the impact of intermittent and volatile wind power generation on the grid is becoming more and more obvious, so the research of wind power prediction method has been widely concerned. Accurate wind power prediction can provide necessary support for the power grid dispatching, combined operation of generating units, operation, and maintenance of wind farms. According to the existing wind power prediction methods, the wind power prediction methods are systematically classified according to the time scale, model object, and model principle of prediction. The physical methods, statistical methods include single and ensemble prediction methods related to wind power prediction are introduced in detail. The error evaluation indicator of the prediction method is analyzed, and the advantages and disadvantages of each prediction method and its applicable occasions are given. At the same time, in view of the existing problems in the wind power prediction method, the corresponding improvement plan is put forward. Finally, this article points out that the research is needed for wind power prediction in the future.


2012 ◽  
Vol 263-266 ◽  
pp. 1279-1284
Author(s):  
Xiu Yan Wang ◽  
Cui Fang Li ◽  
Zong Shuai Li ◽  
Jia Quan Lin

Airfield lighting circuit is an important part of airfield lighting system, and the insulation resistance value of this circuit is affected by humidity, temperature, the quality and the number of the Isolation Transformers and many other factors, so it is difficult to accurately predict the resistance size by using traditional methods. In the light of insulation resistance values of airfield lighting circuit, this paper put forward adopting Gray System Theory to make the prediction, and then build GM(2,1) model to analyze and forecast the resistance values according to the actually measured values of the insulation resistance at Shanghai Pudong International Airport. Finally, the research shows that there is only a little difference between predicted values and the actually measured values. In other words, the prediction of insulation resistance based on Gray System Theory is viable.


2012 ◽  
Vol 616-618 ◽  
pp. 450-454 ◽  
Author(s):  
Hai Dong Meng ◽  
Dong Yuan Zang ◽  
Yu Chen Song

Because the variation of mine gas concentration is influenced by various factors, so it’s impossible for traditional prediction methods of mine gas emission to include all the factors. To solve the problem, the paper proposed a prediction method of mine gas emission based on AR model of time series analysis. The experiment results indicated that the method can predict mine gas emission accurately.


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