Topics in Development of Naval Architecture Software Applications

2013 ◽  
Author(s):  
Kevin McTaggart ◽  
David Heath ◽  
James Nickerson ◽  
Shawn Oakey ◽  
James Van Spengen
Keyword(s):  
Human Resources ◽  
Programming Languages ◽  
Ship Motion ◽  
Motion Prediction ◽  
Naval Architecture ◽  
Software Applications ◽  
Software Documentation ◽  
Wave Radar ◽  
Directional Wave ◽  
Replenishment At Sea

Software applications are used extensively in the practice of contemporary naval architecture. This paper describes several naval architecture applications, including ship motion prediction, simulation of replenishment at sea, simulation of launch and recovery, ship operator guidance, and measurement of directional wave spectra using wave radar. Within this context, this paper describes relevant technologies and programming languages that are effective for development of naval architecture software applications. Due to the complexity of naval architecture software, discussion is given on matching of human resources to software development tasks. Software documentation, which can take several forms, is addressed. Verification and validation of software is the final major topic.

SHIP MOTIONS DURING REPLENISHMENT AT SEA OPERATIONS IN HEAD SEAS

2021 ◽  
Vol 152 (A4) ◽  
Author(s):  
G Thomas ◽  
T Turner ◽  
T Andrewartha ◽  
B Morris
Keyword(s):  
Experimental Study ◽  
Green Function ◽  
Prediction Method ◽  
Ship Motion ◽  
Motion Prediction ◽  
Ship Motions ◽  
Forward Speed ◽  
Theoretical Predictions ◽  
Relative Separation ◽  
Replenishment At Sea

During replenishment at sea operations the interaction between the two vessels travelling side by side can cause significant motions in the smaller vessel and affect the relative separation between their replenishment points. A study into these motions has been conducted including theoretical predictions and model experiments. The model tests investigated the influence of supply ship displacement and longitudinal separation on the ships’ motions. The data obtained from the experimental study has been used to validate a theoretical ship motion prediction method based on a 3-D zero-speed Green function with a forward speed correction in the frequency domain. The results were also used to estimate the expected extreme roll angle of the receiving vessel, and the relative motion between the vessels, during replenishment at sea operations in a typical irregular seaway. A significant increase in the frigate’s roll response was found to occur with an increase of the supply ship displacement, whilst a reduction in motion for the receiving vessel resulted from an increase in longitudinal separation between the vessels. It is proposed that to determine the optimal vessel separation it is vital that the motions of the vessels are not considered in isolation and all motions need to be considered for both vessels simultaneously.

Prediction Error Statistics in Deterministic Linear Ship Motion Forecasting

2018 ◽  
Author(s):  
Fabio Fucile ◽  
Gabriele Bulian ◽  
Claudio Lugni
Keyword(s):  
Prediction Error ◽  
Theoretical Background ◽  
Ship Motion ◽  
Irregular Waves ◽  
Motion Prediction ◽  
Ship Motions ◽  
Error Statistics ◽  
Numerical Application ◽  
Analytical Methodology ◽  
Wave Radar

Deterministic ship motions predictions methodologies represent a promising emerging approach, which could be embedded in decision support systems for certain types of operation. The typically envisioned prediction chain starts from the remote sensing of the wave elevation through wave radar technology. An estimated wave field is then fitted to the data, it is propagated in space and time, and it is finally fed to a ship motion prediction model. Prediction time horizons, typically, are practically limited to the order of minutes. Deterministic predictions are, however, inevitably associated with prediction uncertainty which is seldom quantified. This paper, therefore, presents a semi-analytical methodology for the estimation of ship motion prediction error statistics in ensemble domain as function of the forecasting time, assuming linear Gaussian irregular waves and stationary linear ship motions. This information can be used, for instance, to supplement deterministic forecasting with corresponding confidence intervals. The paper describes the theoretical background of the developed methodology and reports some numerical application examples.

Evaluation of Multi-Vessel Ship Motion Prediction Codes

2008 ◽  
Author(s):  
A. L. Silver ◽  
M. J. Hughes ◽  
R. E. Conrad ◽  
S. S. Lee ◽  
J. T. Klamo ◽  
...  
Keyword(s):  
Ship Motion ◽  
Motion Prediction

Multiscale attention-based LSTM for ship motion prediction

2021 ◽  
Vol 230 ◽  
pp. 109066
Author(s):  
Tao Zhang ◽  
Xiao-Qing Zheng ◽  
Ming-Xin Liu
Keyword(s):  
Ship Motion ◽  
Motion Prediction

Parameterization of Directional Spectra and Its Influence on Ship Motion Predictions

1993 ◽  
Vol 37 (02) ◽  
pp. 138-147
Author(s):  
Ross Graham ◽  
Barbara-Ann Juszko
Keyword(s):  
Spectral Data ◽  
Field Data ◽  
Ship Motion ◽  
Flight Operations ◽  
Modeling Accuracy ◽  
Directional Wave ◽  
Made In

An approach to parameterizing directional spectra proposed by Hogben & Cobb based on a combination of the Ochi & Hubble 6-parameter spectrum and the Longuet-Higgins et al cos2p model is adopted for a study of directional parameterizations and their influence on ship motion predictions. Two schemes for evaluating the directional spreading parameters are assessed in terms of their ability to reproduce highly resolved measured directional spectra, and the best approach, termed the 10-parameter spectrum, is adopted. The applicability of the 10-parameter spectrum to hindcast spectra is investigated, and acceptable fits obtained for 93% of the spectra considered. An evaluation of the ability of the hindcast model to reproduce the measured spectral data is also made. In general, it is found that the differences between the hindcast spectra and associated 10-parameter fits are significantly smaller than the differences between the hindcast spectra and the field data, and it is concluded that the 10-parameter spectrum is a suitable basis for developing statistical descriptions of directional wave climates. The effects of directional parameterization on ship motion predictions are investigated by computing the ship responses as a function of heading for sample hindcast spectra, and the associated 10-parameter and Bretschneider 2-parameter spectra. The responses calculated using the 10-parameter spectrum are found to be in better agreement with the hindcast results than those obtained with the Bretschneider 2-parameter spectrum, with a significant improvement in modeling accuracy in the case of bi-modal spectra. The potential advantages of incorporating the 10-parameter spectrum in future operability analyses of flight operations is examined by comparing the head-to-wind roll response computed using hindcast spectra with that predicted using 10-parameter and Bretschneider spectra.

scholarly journals Using the Big Data in the human resources management systems

2018 ◽  
Vol 8 (3) ◽  
pp. 129-133
Author(s):  
Goker Oge ◽  
Murat Topaloglu
Keyword(s):  
Big Data ◽  
Human Resources ◽  
Programming Languages ◽  
File System ◽  
Labour Force ◽  
Human Resources Management ◽  
Data Entry ◽  
Resources Management ◽  
Personnel Recruitment ◽  
System File

Measures like setting a destination, evaluation of performances, planning of the labour force about business, personnel recruitment, charging of personnel, informations about personnel, analytical of labour force and reporting, etc., are considered as vital problems of the human resources management. In this study, these criteria in a variety of data were collected with a large repository Apache Hadoop Distributed File System file system owned. Data entry and analysis were used Apache Pig and Java programming languages. The aim of the study is to help ‘the owners of business’ evaluate the abundance of data and to get rid of the management complexity via an application which is the biggest problem of management system in human resources. Keywords: Big Data, management of human resources, Hadoop, Pig, map-reduce

scholarly journals HARBOR STUDY FOR SAN NICOLAS BAY, PERU

1970 ◽  
Vol 1 (12) ◽  
pp. 133
Author(s):  
James M. Keith ◽  
Emmett J. Murphy
Keyword(s):  
Particle Velocity ◽  
Time Lapse ◽  
Wave Action ◽  
Ship Motion ◽  
Long Period ◽  
Wave Property ◽  
Directional Wave ◽  
Detailed Interpretation ◽  
Wave Phenomena ◽  
Insight Into

A pair of ducted impeller current meters, one mounted vertically and the other horizontally, were used to measure wave action at San Nicolas Harbor, Peru The horizontal water velocity records are superior to conventional wave records because they measure directly the wave property which induces adverse horizontal ship motion, and provide directional wave data Spectral analysis methods proved well-suited to detailed interpretation of the particle velocity records, while considerable insight into the wave phenomena was gained by simple, rational inspections and interpretations of the records Time-lapse movies of a moored ship, when correlated with simultaneous water particle velocity records, provided an exceptionally clear picture of ship response to wave action, and led to the rather surprising observation that long-period ship motion is not necessarily caused by long-period waves The foregoing ship response was duplicated in hydrau1ic model tests.

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