Wave Height Distribution Observed by Ships in the North Atlantic

DEFF Research Database (Denmark)

Olsen, Anders Smærup; Schrøter, Carsten; Jensen, Jørgen Juncher

2005-01-01

for the significant wave height, the relative speed and the ship heading relative to the wave direction is given. This distribution shows that for higher waves the crews avoid sailing in following sea and as expected the speed is decreased in higher waves. There is, however, still a relatively high probability...

Ship-induced solitary Riemann waves of depression in Venice Lagoon

Energy Technology Data Exchange (ETDEWEB)

Parnell, Kevin E. [College of Marine and Environmental Sciences and Centre for Tropical Environmental and Sustainability Sciences, James Cook University, Queensland 4811 (Australia); Institute of Cybernetics at Tallinn University of Technology, Akadeemia tee 21, 12618 Tallinn (Estonia); Soomere, Tarmo, E-mail: soomere@cs.ioc.ee [Institute of Cybernetics at Tallinn University of Technology, Akadeemia tee 21, 12618 Tallinn (Estonia); Estonian Academy of Sciences, Kohtu 6, 10130 Tallinn (Estonia); Zaggia, Luca [Institute of Marine Sciences, National Research Council, Castello 2737/F, 30122 Venice (Italy); Rodin, Artem [Institute of Cybernetics at Tallinn University of Technology, Akadeemia tee 21, 12618 Tallinn (Estonia); Lorenzetti, Giuliano [Institute of Marine Sciences, National Research Council, Castello 2737/F, 30122 Venice (Italy); Rapaglia, John [Sacred Heart University Department of Biology, 5151 Park Avenue, Fairfield, CT 06825 (United States); Scarpa, Gian Marco [Università Ca' Foscari, Dorsoduro 3246, 30123 Venice (Italy)

2015-03-06

We demonstrate that ships of moderate size, sailing at low depth Froude numbers (0.37–0.5) in a navigation channel surrounded by shallow banks, produce depressions with depths up to 2.5 m. These depressions (Bernoulli wakes) propagate as long-living strongly nonlinear solitary Riemann waves of depression substantial distances into Venice Lagoon. They gradually become strongly asymmetric with the rear of the depression becoming extremely steep, similar to a bore. As they are dynamically similar, air pressure fluctuations moving over variable-depth coastal areas could generate meteorological tsunamis with a leading depression wave followed by a devastating bore-like feature. - Highlights: • Unprecedently deep long-living ship-induced waves of depression detected. • Such waves are generated in channels with side banks under low Froude numbers. • The propagation of these waves is replicated using Riemann waves. • Long-living waves of depression form bore-like features at rear slope.

Ship-induced solitary Riemann waves of depression in Venice Lagoon

International Nuclear Information System (INIS)

Parnell, Kevin E.; Soomere, Tarmo; Zaggia, Luca; Rodin, Artem; Lorenzetti, Giuliano; Rapaglia, John; Scarpa, Gian Marco

2015-01-01

We demonstrate that ships of moderate size, sailing at low depth Froude numbers (0.37–0.5) in a navigation channel surrounded by shallow banks, produce depressions with depths up to 2.5 m. These depressions (Bernoulli wakes) propagate as long-living strongly nonlinear solitary Riemann waves of depression substantial distances into Venice Lagoon. They gradually become strongly asymmetric with the rear of the depression becoming extremely steep, similar to a bore. As they are dynamically similar, air pressure fluctuations moving over variable-depth coastal areas could generate meteorological tsunamis with a leading depression wave followed by a devastating bore-like feature. - Highlights: • Unprecedently deep long-living ship-induced waves of depression detected. • Such waves are generated in channels with side banks under low Froude numbers. • The propagation of these waves is replicated using Riemann waves. • Long-living waves of depression form bore-like features at rear slope

Dynamic selection of ship responses for estimation of on-site directional wave spectra

DEFF Research Database (Denmark)

Andersen, Ingrid Marie Vincent; Storhaug, Gaute

2012-01-01

-estimate of the wave spectrum is suggested. The selection method needs to be robust for what reason a parameterised uni-directional, two-parameter wave spectrum is treated. The parameters included are the zero up-crossing period, the significant wave height and the main wave direction relative to the ship’s heading...... with the best overall agreement are selected for the actual estimation of the directional wave spectrum. The transfer functions for the ship responses can be determined using different computational methods such as striptheory, 3D panel codes, closed form expressions or model tests. The uncertainty associated......Knowledge of the wave environment in which a ship is operating is crucial for most on-board decision support systems. Previous research has shown that the directional wave spectrum can be estimated by the use of measured global ship responses and a set of transfer functions determined...

Stochastic procedures for extreme wave induced responses in flexible ships

DEFF Research Database (Denmark)

Jensen, Jørgen Juncher; Andersen, Ingrid Marie Vincent; Seng, Sopheak

2014-01-01

Different procedures for estimation of the extreme global wave hydroelastic responses in ships are discussed. Firstly, stochastic procedures for application in detailed numerical studies (CFD) are outlined. The use of the First Order Reliability Method (FORM) to generate critical wave episodes...

A Semi-Analytical Method for the PDFs of A Ship Rolling in Random Oblique Waves

Science.gov (United States)

Liu, Li-qin; Liu, Ya-liu; Xu, Wan-hai; Li, Yan; Tang, You-gang

2018-03-01

The PDFs (probability density functions) and probability of a ship rolling under the random parametric and forced excitations were studied by a semi-analytical method. The rolling motion equation of the ship in random oblique waves was established. The righting arm obtained by the numerical simulation was approximately fitted by an analytical function. The irregular waves were decomposed into two Gauss stationary random processes, and the CARMA (2, 1) model was used to fit the spectral density function of parametric and forced excitations. The stochastic energy envelope averaging method was used to solve the PDFs and the probability. The validity of the semi-analytical method was verified by the Monte Carlo method. The C11 ship was taken as an example, and the influences of the system parameters on the PDFs and probability were analyzed. The results show that the probability of ship rolling is affected by the characteristic wave height, wave length, and the heading angle. In order to provide proper advice for the ship's manoeuvring, the parametric excitations should be considered appropriately when the ship navigates in the oblique seas.

Wave energy extraction using decommisioned ships

DEFF Research Database (Denmark)

Mansour, A.E.; Pedersen, Preben Terndrup; Paik, J.K.

2013-01-01

is to tune the ship to have rigid body resonance, or close to it, and resist that motion to absorb power. A hydraulic ramp connected to an accumulator feeding a hydraulic motor that generates power is one possibility. Several other energy extraction mechanisms such as turbines connected to oscillating water...

Analysis for the amplitude oscillatory movements of the ship in response to the incidence wave

Science.gov (United States)

Chiţu, M. G.; Zăgan, R.; Manea, E.

2015-11-01

Event of major accident navigation near offshore drilling rigs remains unacceptably high, known as the complications arising from the problematic of the general motions of the ship sailing under real sea. Dynamic positioning system is an effective instrument used on board of the ships operating in the extraction of oil and gas in the continental shelf of the seas and oceans, being essential that the personnel on board of the vessel can maintain position and operating point or imposed on a route with high precision. By the adoption of a strict safety in terms of handling and positioning of the vessel in the vicinity of the drilling platform, the risk of accidents can be reduced to a minimum. Possibilities in anticipation amplitudes of the oscillatory movements of the ships navigating in real sea, is a challenge for naval architects and OCTOPUS software is a tool used increasingly more in this respect, complementing navigational facilities offered by dynamic positioning systems. This paper presents a study on the amplitudes of the oscillations categories of supply vessels in severe hydro meteorological conditions of navigation. The study provides information on the RAO (Response Amplitude Operator) response operator of the ship, for the amplitude of the roll movements, in some incident wave systems, interpreted using the energy spectrum Jonswap and whose characteristics are known (significant height of the wave, wave period, pulsation of the wave). Ship responses are analyzed according to different positioning of the ship in relation to the wave front (incident angle ranging from 10 to 10 degree from 0 to 180), highlighting the value of the ship roll motion amplitude. For the study, was used, as a tool for modeling and simulation, the features offered by OCTOPUS software that allows the study of the computerized behavior of the ship on the waves, in the real conditions of navigation. Program library was used for both the vessel itself and navigation modeling

A Study on Parametric Wave Estimation Based on Measured Ship Motions

DEFF Research Database (Denmark)

Nielsen, Ulrik Dam; Iseki, Toshio

2011-01-01

The paper studies parametric wave estimation based on the ‘wave buoy analogy’, and data and results obtained from the training ship Shioji-maru are compared with estimates of the sea states obtained from other measurements and observations. Furthermore, the estimating characteristics of the param......The paper studies parametric wave estimation based on the ‘wave buoy analogy’, and data and results obtained from the training ship Shioji-maru are compared with estimates of the sea states obtained from other measurements and observations. Furthermore, the estimating characteristics...... of the parametric model are discussed by considering the results of a similar estimation concept based on Bayesian modelling. The purpose of the latter comparison is not to favour the one estimation approach to the other but rather to highlight some of the advantages and disadvantages of the two approaches....

Analysis of added resistance and seakeeping responses in head sea conditions for low-speed full ships using URANS approach

Directory of Open Access Journals (Sweden)

Yoo-Chul Kim

2017-11-01

Full Text Available The KVLCC2 and its modified hull form were investigated in regular head waves using Unsteady Reynolds Averaged Navier–Stokes (URANS methods. The modified KVLCC2 (named KWP-bow KVLCC2 is designed for reducing wave reflection from the bow. Firstly, the original KVLCC2 is studied for verification of the present code and methodology and the computed time history of total resistance and 2DOF motions (heave and pitch for the selected two wave length conditions are directly compared with the results obtained from KRISO towing tank experiment under the identical condition. The predicted added resistance, heave and pitch motion RAOs show relatively good agreement with the experimental results. Secondly, the comparison of performance in waves between KVLCC2 and KWP-bow KVLCC2 is carried out. We confirmed that newly designed hull form shows better performances in all the range of wave length conditions through both the computation and the experiment. The present URANS method can capture the difference of performance in waves of the two hull forms without any special treatment for short wave length conditions. It can be identified that KWP-bow KVLCC2 gives about 8% of energy saving in sea state 5 condition. Keywords: Added resistance in waves, Ship motion, URANS, KVLCC2

Optimization of the ship type using waveform by means of Rankine source method; Rankine source ho ni yoru hakei wo mochiita funagata saitekika ni tsuite

Energy Technology Data Exchange (ETDEWEB)

Hirayama, A; Eguchi, T [Mitsui Engineering and Shipbuilding Co. Ltd., Tokyo (Japan)

1996-04-10

Among the numerical calculation methods for steady-state wave-making problems, the panel shift Rankine source (PSRS) method has the advantages of rather precise determination of wave pattern of practical ship types, and short calculation period. The wave pattern around the hull was calculated by means of the PSRS method. The waveform analysis was carried out for the wave, to obtain an amplitude function of the original ship type. Based on the amplitude function, a ship type improvement method aiming at the optimization of ship type was provided using a conditional calculus of variation. A Series 60 (Cb=0.6) ship type was selected for the ship type improvement, to apply this technique. It was suggested that optimum design can be made for reducing the wave making resistance by means of this method. For the improvement of Series 60 ship type using this method, a great degree of reduction in the wave making resistance was recognized from the results of numerical waveform analysis. It was suggested that the ship type improvement aiming at the reduction of wave-making resistance can be made in shorter period and by smaller labor compared with the method using a waveform analysis of cistern tests. 5 refs., 9 figs.

Time-domain Hydroelasticity Theory of Ships Responding to Waves

DEFF Research Database (Denmark)

Xia, Jinzhu; Wang, Zhaohui

1997-01-01

free surface flow. The general interface boundary condition is used in the mathematical formulation of the fluid motion around the flexible structure. The general time-domain theory is simplified to a slender-body theory for the analysis of wave-induced global responses of monohull ships. The structure...... is represented by a non-uniform beam, while the generalized hydrodynamic coefficients can be obtained from two-dimensional potential flow theory. The linear slender body theory is generalized to treat the non-linear loading effects of rigid motion and structural response of ships travelling in rough seas....... The non-linear hydrostatic restoring force and hydrodynamic momentum action are considered. A numerical solution is presented for the slender body theory. Numerical examples are given for two ship cases with different geometry features, a warship hull and the S175 containership with two different bow...

Fast Evaluation of Ship Responses in Waves

DEFF Research Database (Denmark)

Jensen, Jørgen Juncher

2004-01-01

The aim of the present paper is to provide a rational and efficient procedure able to predict the design wave-induced motions, accelerations and loads with sufficient engineering accuracy in the conceptual design phase and in risk assessment. The procedure relies only on the following main parame...... parameters of the ship: Length, breadth, draught, block coefficient and water plane area together with the operational profile. The formulas are semi-analytical and the calculations can be easily done using a standard spreadsheet program....

Innovative technologies to accurately model waves and moored ship motions

CSIR Research Space (South Africa)

van der Molen, W

2010-09-01

Full Text Available Late in 2009 CSIR Built Environment in Stellenbosch was awarded a contract to carry out extensive physical and numerical modelling to study the wave conditions and associated moored ship motions, for the design of a new iron ore export jetty for BHP...

Nonlinear dead water resistance at subcritical speed

Science.gov (United States)

Grue, John

2015-08-01

The dead water resistance F 1 = /1 2 C d w ρ S U 2 (ρ fluid density, U ship speed, S wetted body surface, Cdw resistance coefficient) on a ship moving at subcritical speed along the upper layer of a two-layer fluid is calculated by a strongly nonlinear method assuming potential flow in each layer. The ship dimensions correspond to those of the Polar ship Fram. The ship draught, b0, is varied in the range 0.25h0-0.9h0 (h0 the upper layer depth). The calculations show that Cdw/(b0/h0)2 depends on the Froude number only, in the range close to critical speed, Fr = U/c0 ˜ 0.875-1.125 (c0 the linear internal long wave speed), irrespective of the ship draught. The function Cdw/(b0/h0)2 attains a maximum at subcritical Froude number depending on the draught. Maximum Cdw/(b0/h0)2 becomes 0.15 for Fr = 0.76, b0/h0 = 0.9, and 0.16 for Fr = 0.74, b0/h0 = 1, where the latter extrapolated value of the dead water resistance coefficient is about 60 times higher than the frictional drag coefficient and relevant for the historical dead water observations. The nonlinear Cdw significantly exceeds linear theory (Fr < 0.85). The ship generated waves have a wave height comparable to the upper layer depth. Calculations of three-dimensional wave patterns at critical speed compare well to available laboratory experiments. Upstream solitary waves are generated in a wave tank of finite width, when the layer depths differ, causing an oscillation of the force. In a wide ocean, a very wide wave system develops at critical speed. The force approaches a constant value for increasing time.

Ionospheric Bow Wave Induced by the Moon Shadow Ship Over the Continent of United States on 21 August 2017

Science.gov (United States)

Sun, Yang-Yi; Liu, Jann-Yenq; Lin, Charles Chien-Hung; Lin, Chi-Yen; Shen, Ming-Hsueh; Chen, Chieh-Hung; Chen, Chia-Hung; Chou, Min-Yang

2018-01-01

A moon shadow of the total solar eclipse swept through the continent of United States (CONUS) from west to east on 21 August 2017. Massive total electron content (integration of electron density from 0 km to 20,200 km altitude) observations from 2,255 ground-based Global Navigation Satellite System receivers show that the moon shadow ship generates a great ionospheric bow wave front which extends 1,500 km away from the totality path covering the entire CONUS. The bow wave front consists of the acoustic shock wave due to the supersonic/near-supersonic moon shadow ship and the significant plasma recombination due to the reduction in solar irradiation within the shadow area. The deep bow wave trough (-0.02 total electron content unit (1 TECU = 1016 el m-2) area) nearly coincides with the 100% obscuration moving along the totality path over the CONUS through the entire eclipse period. The supersonic moon shadow ship induces a bow wave crest in front of the ship ( 80% obscuration). It is the first time to find the acoustic shock wave-formed bow wave trough and crest near the totality.

Encountered Wave Height Distributions for Ships in the North Atlantic

DEFF Research Database (Denmark)

Olsen, Anders Smærup; Schrøter, C.; Jensen, Jørgen Juncher

2004-01-01

About 20 000 observations of wave heights taken on board vessels sailing in the North Atlantic are presented. The data covers year 2002 and 2003 and stem from a variety of ship types. From the preliminary analysis of the data some conclusions are reached about the effect of weather routing whether...

Calculation of the collision resistance of ships and its assessment for classification purposes

International Nuclear Information System (INIS)

Boeckenhauer, M.; Egge, E.D.

1994-01-01

Within the framework of a research programme ''Tanker Safety'', Germanischer Lloyd has developed a program system for the evaluation of the absorbed plastic deformation energy in a ship-ship collision. The ultimate load capacities of the ship structures in the areas affected by the collision are evaluated stepwise. The total collision energy absorbed by plastic deformations of the ship structures is evaluated on the basis of the minima of the ultimate load capacities and the corresponding penetration depths. By means of the collision energy absorbed, the collision speed necessary to cause damage can be determined.It is now possible to classify ships with regard to their resistance against collisions and to assign relevant class notations.The resistance of a ship against collision impacts is expressed by the class notation COLL with index numbers ranging from 1 to 6. The index numbers indicate that - as compared with a non-strengthened single hull reference ship - a critical situation is likely to occur only if the deformation energy absorbed in the collision exceeds that of the non-strengthened reference ship by specified values.A ''critical situation'' is defined by, for example, rupture of cargo tanks with subsequent spillage of cargo or water ingress into dry cargo holds. ((orig.))

A NUMERICAL APPLICATION TO PREDICT THE RESISTANCE AND WAVE PATTERN OF KRISO CONTAINER SHIP

OpenAIRE

Yavuz Hakan Ozdemir; Taner Cosgun; Ali Dogrul; Boris Barlas

2016-01-01

In this study, the computational results for KRISO Container Ship (KCS) are presented. CFD analyses are performed to simulate free surface flow around KCS by using RANS approach with success. Also the complicated turbulent flow zone behind the ship is well simulated. The RANS equations and the non-linear free surface boundary conditions are discretized by means of a finite volume scheme. The numerical methodology is found to be appropriate for simulating the turbulent flow around a ship in or...

Design of high-speed planing hulls for the improvement of resistance and seakeeping performance

Directory of Open Access Journals (Sweden)

Dong Jin Kim

2013-03-01

Full Text Available High-speed vessels require good resistance and seakeeping performance for safe operations in rough seas. The resistance and seakeeping performance of high-speed vessels varies significantly depending on their hull forms. In this study, three planing hulls that have almost the same displacement and principal dimension are designed and the hydrodynamic characteristics of those hulls are estimated by high-speed model tests. All model ships are deep-V type planing hulls. The bows of no.2 and no.3 model ships are designed to be advantageous for wave-piercing in rough water. No. 2 and no. 3 model ships have concave and straight forebody cross-sections, respectively. And length-to-beam ratios of no.2 and no.3 models are larger than that of no.1 model. In calm water tests, running attitude and resistance of model ships are measured at various speeds. And motion tests in regular waves are performed to measure the heave and pitch motion responses of the model ships. The required power of no.1 (VPS model is smallest, but its vertical motion amplitudes in waves are the largest. No.2 (VWC model shows the smallest motion amplitudes in waves, but needs the greatest power at high speed. The resistance and seakeeping performance of no.3 (VWS model ship are the middle of three model ships, respectively. And in regular waves, no.1 model ship experiences ‘fly over’ phenomena around its resonant frequency. Vertical accelerations at specific locations such as F.P., center of gravity of model ships are measured at their resonant frequency. It is necessary to measure accelerations by accelerometers or other devices in model tests for the accurate prediction of vertical accelerations in real ships.

Blind estimation of a ship's relative wave heading

DEFF Research Database (Denmark)

Nielsen, Ulrik Dam; Iseki, Toshio

2012-01-01

This article proposes a method to estimate a ship’s relative heading against the waves. The procedure relies purely on ship- board measurements of global responses such as motion components, accelerations and the bending moment amidships. There is no particular (mathematical) model connected to t...... to the estimate, and therefore it is called a ’blind estimate’. The approach is in this introductory study tested by analysing simulated data. The analysis reveals that it is possible to estimate a ship’s relative heading on the basis of shipboard measurements only....

Uncertainty Analysis of Resistance Tests in Ata Nutku Ship Model Testing Laboratory of Istanbul Technical University

Directory of Open Access Journals (Sweden)

Cihad DELEN

2015-12-01

Full Text Available In this study, some systematical resistance tests, where were performed in Ata Nutku Ship Model Testing Laboratory of Istanbul Technical University (ITU, have been included in order to determine the uncertainties. Experiments which are conducted in the framework of mathematical and physical rules for the solution of engineering problems, measurements, calculations include uncertainty. To question the reliability of the obtained values, the existing uncertainties should be expressed as quantities. The uncertainty of a measurement system is not known if the results do not carry a universal value. On the other hand, resistance is one of the most important parameters that should be considered in the process of ship design. Ship resistance during the design phase of a ship cannot be determined precisely and reliably due to the uncertainty resources in determining the resistance value that are taken into account. This case may cause negative effects to provide the required specifications in the latter design steps. The uncertainty arising from the resistance test has been estimated and compared for a displacement type ship and high speed marine vehicles according to ITTC 2002 and ITTC 2014 regulations which are related to the uncertainty analysis methods. Also, the advantages and disadvantages of both ITTC uncertainty analysis methods have been discussed.

Containment of spills from ships

International Nuclear Information System (INIS)

Engerer, M.J.

1992-01-01

Oil escaping from a ship is contained within a limited area surrounding the ship by means of a flexible ring structure. The ring structure is stored in a collapsed state in a compartment extending around the ship. In response to an oil spill, the ring structure is dropped from the compartment and immediately surrounds the ship. A circular inflatable flotation section of the ring structure is charged with gas under pressure. The gas is supplied from a bottle cascade aboard the ship, through lines preconnected to the flotation section and paid out from free-wheeling reels. The flotation section supports a thin circumferential wall of predetermined height that submerges and assumes a vertical cylinder-like shape surrounding the escaping oil. The oil floats within the confines of the ring structure, and the ring structure is progressively expanded to a predetermined size selected to accommodate the total volume of oil carried by the ship. When the ring structure achieves its expanded state, pressure in the flotation section is raised to render the structure relatively rigid and resistant to collapse in response to wave action. Oil can be removed from the interior of the ring structure by recovery ships using suction lines or other conventional recovery methods. 12 figs

A numerical study of the second-order wave excitation of ship springing by a higher-order boundary element method

Directory of Open Access Journals (Sweden)

Shao Yan-Lin

2014-12-01

Full Text Available This paper presents some of the efforts by the authors towards numerical prediction of springing of ships. A time-domain Higher Order Boundary Element Method (HOBEM based on cubic shape function is first presented to solve a complete second-order problem in terms of wave steepness and ship motions in a consistent manner. In order to avoid high order derivatives on the body surfaces, e.g. mj-terms, a new formulation of the Boundary Value Problem in a body-fixed coordinate system has been proposed instead of traditional formulation in inertial coordinate system. The local steady flow effects on the unsteady waves are taken into account. Double-body flow is used as the basis flow which is an appropriate approximation for ships with moderate forward speed. This numerical model was used to estimate the complete second order wave excitation of springing of a displacement ship at constant forward speeds.

Prediction of Vertical-Plane Wave Loading and Ship Responses in High Seas

DEFF Research Database (Denmark)

Wang, Z.; Xia, J.; Jensen, Jørgen Juncher

2000-01-01

The non-linearities in wave- and slamming-induced rigid-body motions and structural responses of ships such as heave, pitch and vertical bending moments are consistently investigated based on a rational time-domain strip method. A hydrodynamic model for predicting sectional green water force is a...

Estimation of Ship Long-term Wave-induced Bending Moment using Closed-Form Expressions

DEFF Research Database (Denmark)

Jensen, Jørgen Juncher; Mansour, A. E.

2002-01-01

A semi-analytical approach is used to derive frequency response functions and standard deviations for the wave-induced bending moment amidships for mono-hull ships. The results are given as closed-form expressions and the required input information for the procedure is restricted to the main......-empirical closed-form expression for the skewness. The effect of whipping is included by assuming that whipping and wave-induced responses are conditionally independent given Hs. The procedure is simple and can be used to make quick estimates of the design wave bending moment at the conceptual design phase...

Compensation of Wave-Induced Motion and Force Phenomena for Ship-Based High Performance Robotic and Human Amplifying Systems

Energy Technology Data Exchange (ETDEWEB)

Love, LJL

2003-09-24

The decrease in manpower and increase in material handling needs on many Naval vessels provides the motivation to explore the modeling and control of Naval robotic and robotic assistive devices. This report addresses the design, modeling, control and analysis of position and force controlled robotic systems operating on the deck of a moving ship. First we provide background information that quantifies the motion of the ship, both in terms of frequency and amplitude. We then formulate the motion of the ship in terms of homogeneous transforms. This transformation provides a link between the motion of the ship and the base of a manipulator. We model the kinematics of a manipulator as a serial extension of the ship motion. We then show how to use these transforms to formulate the kinetic and potential energy of a general, multi-degree of freedom manipulator moving on a ship. As a demonstration, we consider two examples: a one degree-of-freedom system experiencing three sea states operating in a plane to verify the methodology and a 3 degree of freedom system experiencing all six degrees of ship motion to illustrate the ease of computation and complexity of the solution. The first series of simulations explore the impact wave motion has on tracking performance of a position controlled robot. We provide a preliminary comparison between conventional linear control and Repetitive Learning Control (RLC) and show how fixed time delay RLC breaks down due to the varying nature wave disturbance frequency. Next, we explore the impact wave motion disturbances have on Human Amplification Technology (HAT). We begin with a description of the traditional HAT control methodology. Simulations show that the motion of the base of the robot, due to ship motion, generates disturbances forces reflected to the operator that significantly degrade the positioning accuracy and resolution at higher sea states. As with position-controlled manipulators, augmenting the control with a Repetitive

Numerical Ship Hydrodynamics : an assessment of the Gothenburg 2010 Workshop

CERN Document Server

Stern, Frederick; Visonneau, Michel

2014-01-01

This book assesses the state-of-the-art in computational fluid dynamics (CFD) applied to ship hydrodynamics and provides guidelines for the future developments in the field based on the Gothenburg 2010 Workshop. It presents ship hull test cases, experimental data and submitted computational methods, conditions, grids and results.  Analysis is made of errors for global (resistance, sinkage and trim and self-propulsion) and local flow (wave elevations and mean velocities and turbulence) variables, including standard deviations for global variables and propeller modeling for self-propulsion. The effects of grid size and turbulence models are evaluated for both global and local flow variables. Detailed analysis is made of turbulence modeling capabilities for capturing local flow physics. Errors are also analyzed for head-wave seakeeping and forward speed diffraction, and calm-water forward speed-roll decay. Resistance submissions are used to evaluate the error and uncertainty by means of a systematic verificatio...

Calculation of wave resistance by using Kochin function in the Rankine source method; Rankinsosuho ni okeru kochin kansu wo mochiita zoha teiko keisan

Energy Technology Data Exchange (ETDEWEB)

Yasukawa, H [Mitsubishi Heavy Industries, Ltd., Tokyo (Japan)

1997-10-01

In order to avoid negative wave resistance (which is physically incomprehensible) generated in calculating wave resistance by using the Rankine source method, a proposal was made on a wave resistance calculation method using the Kochin function which describes behavior of speed potential in regions far apart from a hull. The Baba`s condition was used as a free surface condition for the speed potential which expresses wave motions around a hull. This has allowed a new Kochin function which uses as unknown the speed potential on the hull surface and the free surface near the hull to be defined and combined with the Rankine source method. A comparison was made between the calculated values for wave resistance, hull subsidence and trim change of an ore transporting vessel (SR107 type of ship) in a fully loaded condition and the result of water tank tests. The wave resistance values derived from pressure integration have all become negative when the Froude number is from 0.1 to 0.2, while no negative resistance has appeared in the calculations by using the Kochin function, but the result has agreed with that of the water tank tests. Accuracy of the calculations at low speeds was improved. The trim change in the calculations was slightly smaller than that in the water tank tests. The subsidence showed a good agreement. 7 refs., 1 fig.

A high-order finite-difference linear seakeeping solver tool for calculation of added resistance in waves

DEFF Research Database (Denmark)

Amini Afshar, Mostafa; Bingham, Harry B.; Read, Robert

During recent years a computational strategy has been developed at the Technical University of Denmark for numerical simulation of water wave problems based on the high-order nite-dierence method, [2],[4]. These methods exhibit a linear scaling of the computational eort as the number of grid points...... increases. This understanding is being applied to develop a tool for predicting the added resistance (drift force) of ships in ocean waves. We expect that the optimal scaling properties of this solver will allow us to make a convincing demonstration of convergence of the added resistance calculations based...... on both near-eld and far-eld methods. The solver has been written inside a C++ library known as Overture [3], which can be used to solve partial dierential equations on overlapping grids based on the high-order nite-dierence method. The resulting code is able to solve, in the time domain, the linearised...

Non-linear wave loads and ship responses by a time-domain strip theory

DEFF Research Database (Denmark)

Xia, Jinzhu; Wang, Zhaohui; Jensen, Jørgen Juncher

1998-01-01

. Based on this time-domain strip theory, an efficient non-linear hydroelastic method of wave- and slamming-induced vertical motions and structural responses of ships is developed, where the structure is represented as a Timoshenko beam. Numerical calculations are presented for the S175 Containership...

Non-Linear Wave Loads and Ship responses by a time-domain Strip Theory

DEFF Research Database (Denmark)

Xia, Jinzhu; Wang, Zhaohui; Jensen, Jørgen Juncher

1998-01-01

. Based on this time-domain strip theory, an efficient non-linear hyroelastic method of wave- and slamming-induced vertical motions and structural responses of ships is developed, where the structure is represented by the Timoshenko beam theory. Numerical calculations are presented for the S175...

Study of Green Shipping Technologies - Harnessing Wind, Waves and Solar Power in New Generation Marine Propulsion Systems

Directory of Open Access Journals (Sweden)

Grzegorz Rutkowski

2016-12-01

Full Text Available The purpose and scope of this paper is to describe the complexity of the new generation marine propulsion technologies implemented in the shipping industry to promote green ships concept and change the view of sea transportation to a more ecological and environment-friendly. Harnessing wind, waves and solar power in shipping industry can help the ship’s owners reduce the operational costs. Reducing fuel consumption results in producing less emissions and provides a clean source of renewable energy. Green shipping technologies can also effectively increase the operating range of vessels and help drive sea transportation towards a greener future and contribute to the global reduction of harmful gas emissions from the world's shipping fleets.

Analysis Of Resistance And Effective Wake Friction Due To Addition Of Stern Tunnels On Passenger Ship Using Cfd

Science.gov (United States)

Chrismianto, D.; Tuswan; Manik, P.

2018-03-01

In this study, the stern tunnel to improve the efficiency of ship propulsion system is analysed. Stern tunnels installed on the two sides of the ship stern. Analysis of ship resistance and wake friction of the ship using CFD are carried out. The stern tunnel height (Hw) and length (L) are implemented to find the better stern tunnel form of the ship. The result of analysis showed that model has a high stern tunnels (Hw) of 1,444 m or additional high stern tunnels ratio of 16% and stern long tunnels (L) about 7 m is a model that has the smallest resistance about 1.1137 N or able to make reduction of resistance amount 11.2582%. While, the model with the addition of height of 0.2 m and a length of 9 m of stern tunnel is a model that has the better advanced speed about 4,927% in increase, and better wake friction about 30.4% in reduce.

Study on variation in ship's forward speed under regular waves depending on rudder controller

Directory of Open Access Journals (Sweden)

Sung-Soo Kim

2015-03-01

Full Text Available The purpose of this research is to compare and analyze the advanced speed of ships with different rudder controller in wavy condition by using a simulation. The commercial simulation tool named AQWA is used to develop the simulation of ship which has 3 degree of freedom. The nonlinear hydrodynamic force acting on hull, the propeller thrust and the rudder force are calculated by the additional subroutine which interlock with the commercial simulation tool, and the regular wave is used as the source of the external force for the simulation. Rudder rotational velocity and autopilot coefficients vary to make the different rudder controller. An advanced speed of ships depending on the rudder controller is analyzed after the autopilot simulations.

Drag resistance measurements for newly applied antifouling coatings and welding seams on ship hull surface

DEFF Research Database (Denmark)

Wang, Xueting; Olsen, S. M.; Andres, E.

Drag resistances of newly applied antifouling coatings and welding seams on ship hull surface have been investigated using a pilot-scale rotary setup. Both conventional biocide-based antifouling (AF) coatings and silicone-based fouling release (FR) coatings have been studied and compared in their......Drag resistances of newly applied antifouling coatings and welding seams on ship hull surface have been investigated using a pilot-scale rotary setup. Both conventional biocide-based antifouling (AF) coatings and silicone-based fouling release (FR) coatings have been studied and compared...

Flow measurement around a model ship with propeller and rudder

Energy Technology Data Exchange (ETDEWEB)

Van, S H; Yoon, H S; Lee, Y Y; Park, I R [Korea Research Institute of Ships and Ocean Engineering, KORDI, Marine Transportation Systems Laboratory, Daejeon (Korea); Kim, W J [Mokpo National University, Department of Naval Architecture and Marine Engineering, Jeonnam (Korea)

2006-04-15

For the design of hull forms with better resistance and propulsive performance, it is essential to understand flow characteristics, such as wave and wake development, around a ship. Experimental data detailing the local flow characteristics are invaluable for the validation of the physical and numerical modeling of computational fluid dynamics (CFD) codes, which are recently gaining attention as efficient tools for hull form evaluation. This paper describes velocity and wave profiles measured in the towing tank for the KRISO 138,000 m{sup 3} LNG carrier model with propeller and rudder. The effects of propeller and rudder on the wake and wave profiles in the stern region are clearly identified. The results contained in this paper can provide an opportunity to explore integrated flow phenomena around a model ship in the self-propelled condition, and can be added to the International Towing Tank Conference benchmark data for CFD validation as the previous KCS and KVLCC cases. (orig.)

Flow measurement around a model ship with propeller and rudder

Science.gov (United States)

van, S. H.; Kim, W. J.; Yoon, H. S.; Lee, Y. Y.; Park, I. R.

2006-04-01

For the design of hull forms with better resistance and propulsive performance, it is essential to understand flow characteristics, such as wave and wake development, around a ship. Experimental data detailing the local flow characteristics are invaluable for the validation of the physical and numerical modeling of computational fluid dynamics (CFD) codes, which are recently gaining attention as efficient tools for hull form evaluation. This paper describes velocity and wave profiles measured in the towing tank for the KRISO 138,000 m3 LNG carrier model with propeller and rudder. The effects of propeller and rudder on the wake and wave profiles in the stern region are clearly identified. The results contained in this paper can provide an opportunity to explore integrated flow phenomena around a model ship in the self-propelled condition, and can be added to the International Towing Tank Conference benchmark data for CFD validation as the previous KCS and KVLCC cases.

Automation of measurement of heights waves around a model ship; Mokeisen mawari no hako keisoku no jidoka

Energy Technology Data Exchange (ETDEWEB)

Ikehata, M; Kato, M; Yanagida, F [Yokohama National University, Yokohama (Japan). Faculty of Engineering

1997-10-01

Trial fabrication and tests were performed on an instrument to automate measurement of heights of waves around a model ship. The currently used electric wave height measuring instrument takes long time for measurement, hence poor in efficiency. The method for processing optical images also has a problem in accuracy. Therefore, a computer controlled system was structured by using AC servo motors in driving the X and Y axes of a traverse equipment. Equipment was fabricated to automate the wave height measurement, in which four servo type wave height meters are installed on a moving rack in the lateral (Y-axial) direction so that wave heights to be measured by four meters can be measured automatically all at once. Wave heights can be measured continuously by moving the moving rack at a constant speed, verifying that wave shapes in longitudinal cross sections can be acquired by only one towing. Time required in the measurements using the instrument was 40 hours as a net time for fixed point measurement and 12 hours for continuous measurement, or 52 hours in total. On the other hand, the time may reach 240 hours for fixed point measurement when the conventional all-point manual traverse equipment is used. Enormous effects were obtained from automating the instrument. Collection of wave height data will continue also on tankers and other types of ships. 2 refs., 8 figs., 1 tab.

Global ship accidents and ocean swell-related sea states

Directory of Open Access Journals (Sweden)

Z. Zhang

2017-11-01

Full Text Available With the increased frequency of shipping activities, navigation safety has become a major concern, especially when economic losses, human casualties and environmental issues are considered. As a contributing factor, the sea state plays a significant role in shipping safety. However, the types of dangerous sea states that trigger serious shipping accidents are not well understood. To address this issue, we analyzed the sea state characteristics during ship accidents that occurred in poor weather or heavy seas based on a 10-year ship accident dataset. Sea state parameters of a numerical wave model, i.e., significant wave height, mean wave period and mean wave direction, were analyzed for the selected ship accident cases. The results indicated that complex sea states with the co-occurrence of wind sea and swell conditions represent threats to sailing vessels, especially when these conditions include similar wave periods and oblique wave directions.

Global ship accidents and ocean swell-related sea states

Science.gov (United States)

Zhang, Zhiwei; Li, Xiao-Ming

2017-11-01

With the increased frequency of shipping activities, navigation safety has become a major concern, especially when economic losses, human casualties and environmental issues are considered. As a contributing factor, the sea state plays a significant role in shipping safety. However, the types of dangerous sea states that trigger serious shipping accidents are not well understood. To address this issue, we analyzed the sea state characteristics during ship accidents that occurred in poor weather or heavy seas based on a 10-year ship accident dataset. Sea state parameters of a numerical wave model, i.e., significant wave height, mean wave period and mean wave direction, were analyzed for the selected ship accident cases. The results indicated that complex sea states with the co-occurrence of wind sea and swell conditions represent threats to sailing vessels, especially when these conditions include similar wave periods and oblique wave directions.

Towards Real Time Simulation of Ship-Ship Interaction

DEFF Research Database (Denmark)

Lindberg, Ole; Bingham, Harry B.; Engsig-Karup, Allan Peter

2012-01-01

We present recent and preliminary work directed towards the development of a simplified, physics-based model for improved simulation of ship-ship interaction that can be used for both analysis and real-time computing (i.e. with real-time constraints due to visualization). The goal is to implement...... accurate (realistic) and much faster ship-wave and ship-ship simulations than are currently possible. The coupling of simulation with visualization should improve the visual experience such that it can be perceived as more realistic in training. Today the state-of-art in real-time ship-ship interaction...... is for efficiency reasons and time-constraints in visualization based on model experiments in towing tanks and precomputed force tables. We anticipate that the fast, and highly parallel, algorithm described by Engsig-Karup et al. [2011] for execution on affordable modern high-throughput Graphics Processing Units...

Total Analysis System for Ship Structural Strength

OpenAIRE

Takuya, Yoneya; Hiroyuki, Kobayashi; Abdul M., Rahim; Yoshimichi, Sasaki; Masaki, Irisawa; Technical Investigation and Information Department, Research Center; Technical Investigation and Information Department, Research Center; Singapore Office; Technical Investigation and Information Department, Research Center; Technical Investigation and Information Department, Research Center

2001-01-01

This paper outlines a total analysis system for ship hull structures, which integrates a wide variety of analysis functions to realise practical applications of rational methods for assessing ship structural strength. It is based on direct calculation of wave-induced loads as well as three-dimensional structural analysis of an entire-ship or hold structure. Three major analysis functions of the total system are ship motion and wave load analysis, ship structural analysis and statistical analy...

Creating an anisotropic plasma resistivity with waves

International Nuclear Information System (INIS)

Fisch, N.J.; Boozer, A.H.

1980-05-01

An anisotropic plasma resistivity may be created by preferential heating of electrons traveling in one direction. This can result in a steady-state toroidal current in a tokamak even in the absence of net wave momentum. In fact, at high wave phase velocities, the current associated with the change in resistivity is greater than that associated with net momentum input. An immediate implication is that other waves, such as electron cyclotron waves, may be competitive with lower-hybrid waves as a means for generating current. An analytical expression is derived for the current generated per power dissipated which agrees remarkably well with numerical calculations

Investigation of the Effects of Ship Induced Waves on the Littoral Zone with Field Measurements and CFD Modeling

Directory of Open Access Journals (Sweden)

Gábor Fleit

2016-07-01

Full Text Available Waves induced by ship movement might be harmful for the habitat in the littoral zone of rivers due to the temporally increasing bed shear stress, the high-energy breaking waves and the consequently related detachment of benthic animals. In order to understand the complex hydrodynamic phenomena resulting from littoral waves, we present the testing of a novel methodology that incorporates field observations and numerical tools. The study is performed at a section of the Danube River in Hungary and analyzes the influence of different ship types. The field methods consist of parallel acoustic measurements (using Acoustic Doppler Velocimetry (ADV conducted at the riverbed and Large Scale Particle Image Velocimetry (LSPIV of the water surface. ADV measurements provided near-bed flow velocities based on which the wave induced currents and local bed shear stress could be estimated. The LSPIV was able to quantify the dynamics of the breaking waves along the bank. Furthermore, computational fluid dynamics (CFD modeling was successfully applied to simulate the propagation and the breaking of littoral waves. The used techniques complement each other well and their joint application provides an adequate tool to support the improvement of riverine habitats.

Observations and computations of narrow Kelvin ship wakes

Directory of Open Access Journals (Sweden)

Francis Noblesse

2016-01-01

Full Text Available Computations of far-field ship waves, based on linear potential flow theory and the Hogner approximation, are reported for monohull ships and catamarans. Specifically, far-field ship waves are computed for six monohull ships at four Froude numbers F≡V/gL=0.58, 0.68, 0.86, 1.58 and for six catamarans with nondimensional hull spacing s≡S/L=0.25 at two Froude numbers Fs≡V/gS=1 and 2.5. Here, g is the gravitational acceleration, V and L denote the ship speed and length, and S is the separation distance between the twin hulls of a catamaran. The computations show that, although the amplitudes of the waves created by a ship are strongly influenced by the shape of the ship hull, as well known, the ray angles where the largest waves are found are only weakly influenced by the hull shape and indeed are mostly a kinematic feature of the flow around a ship hull. An important practical consequence of this flow feature is that the apparent wake angle of general monohull ships or catamarans (with arbitrarily-shaped hulls can be estimated, without computations, by means of simple analytical relations; these relations, obtained elsewhere via parametric computations, are given here. Moreover, the influence of the two parameters Fs and s that largely determine the ray angles of the dominant waves created by a catamaran is illustrated via computations for three catamarans with hull spacings s=0.2, 0.35, 0.5 at four Froude numbers Fs=1, 1.5, 2, 2.5. These computations confirm that the largest waves created by wide and/or fast catamarans are found at ray angles that only depend on Fs (i.e. that do not depend on the hull spacing s in agreement with an elementary analysis of lateral interference between the dominant waves created by the bows (or sterns of the twin hulls of a catamaran. The dominant-waves ray angles predicted by the theory of wave-interference effects for monohull ships and catamarans are also compared with the observations of narrow Kelvin ship

Using an Autonomous Scale Ship Model for Resistance and Parametric Roll Tests

Directory of Open Access Journals (Sweden)

Fernando LOPEZ PEŇA

2015-04-01

Full Text Available This work presents the developing of a self-propelled scale ship model aimed to perform resistance and parametric roll tests in towing tanks. The main characteristic of the proposed system is that it doesn’t have any material link to a towing device to carry out the tests. This ship model has been fully instrumented in order to acquire all the significant raw data, process them onboard and communicate with an inshore station. This works presents a description of the proposed model as well as some results obtained by its use during a towing tank testing campaign.

Consideration on longitudinal bending moment in waves of a large high-speed ship; Ogata kosokutei no haro tatemage moment ni kansuru ichikosatsu

Energy Technology Data Exchange (ETDEWEB)

Deguchi, M; Takimoto, T; Kasuda, T; Tozawa, S [Mitsubishi Heavy Industries, Ltd., Tokyo (Japan)

1996-04-10

While high-speed ships are on a trend of increased speed, size and diversity, one of the most important items is a discussion on large high-speed ships with a total length of 100 m class on their longitudinal strength in waves. With such a background, a model ship intended of realizing a large high-speed was assumed, and verification of reliability in structural strength and establishment of a design method for this ship were intended. Therefore, oceanographic condition setting, design load setting, FEM analysis, and strength assessment were carried out. This paper reports the results of comparison with and consideration on conventional criteria and linear calculations, mainly the results of simulated calculations on non-linear hull movement/wave load which have been performed in discussing the loads. The result of the non-linear simulation is thought to have well simulated non-linearity characteristic to the ship. Conventional criteria which have been arranged on the record of use for small ships are considered impossible to be applied to large high-speed ships. Under such a situation, the simplified equations by Kaneko et al are judged effective in making an initial plan for this type of ship. 6 refs., 7 figs., 2 tabs.

Method for rudder roll stabilization control by maintaining ship speed

Directory of Open Access Journals (Sweden)

LIU Zhiquan

2017-01-01

Full Text Available A ship navigating on the surface of the water may experience greater resistance, adversely affect-ing its speed and leading to energy loss. The added resistance of surface ships in both still water and waves are investigated, and the computation method of total speed loss is presented. An autopilot system is intro-duced to constrain the speed loss, and course keeping and rudder roll stabilization sliding mode control laws are proposed according to a compact control strategy. The two working conditions of "heading" and "heading plus anti-roll" are discussed, including roll stabilization, heading error, speed maintenance and rudder abrasion. The results show that the speed can be effectively maintained using this method, and from a commercial point of view, the fin-rudder roll stabilization control is not recommended for vessels equipped with both fins and rudders.

Experimental and Numerical Analysis of Hull Girder Vibrations and Bow Impact of a Large Ship Sailing in Waves

Directory of Open Access Journals (Sweden)

Jialong Jiao

2015-01-01

Full Text Available It is of great importance to evaluate the hull structural vibrations response of large ships in extreme seas. Studies of hydroelastic response of an ultra large ship have been conducted with comparative verification between experimental and numerical methods in order to estimate the wave loads response considering hull vibration and water impact. A segmented self-propelling model with steel backbone system was elaborately designed and the experiments were performed in a tank. Time domain numerical simulations of the ship were carried out by using three-dimensional nonlinear hydroelasticity theory. The results from the computational analyses have been correlated with those from model tests.

INFLUENCE OF OPERABILITY CRITERIA LIMITING VALUES ON SHIP SPEED

Directory of Open Access Journals (Sweden)

Jasna Prpić-Oršić

2016-09-01

Full Text Available When the ship is caught in heavy seas, there are two manoeuvres that the shipmaster can undertake to avoid excessive ship motion and hull damage: changing course or voluntary speed reduction. This paper presents a study of the effect of the various voluntary speed reduction criteria to attainable speed of ship on seaway. The speed loss is calculated by taking into account wind and wave effect on ship speed, the engine and propeller performance in actual seas as well as the mass inertia of the ship. The attainable ship speed for ship in head, following and beam waves by accounting for voluntary speed reduction is estimated for various significant wave height. The criteria of slamming, deck wetness, propeller emergence, excessive accelerations and roll are taken into account. The impact of variations of the limiting values of certain criteria due to which the captain intentionally reduces the ship speed is analysed and discussed.

Observations and computations of narrow Kelvin ship wakes

OpenAIRE

Francis Noblesse; Chenliang Zhang; Jiayi He; Yi Zhu; Chenjun Yang; Wei Li

2016-01-01

Computations of far-field ship waves, based on linear potential flow theory and the Hogner approximation, are reported for monohull ships and catamarans. Specifically, far-field ship waves are computed for six monohull ships at four Froude numbers F≡V/gL=0.58, 0.68, 0.86, 1.58 and for six catamarans with nondimensional hull spacing s≡S/L=0.25 at two Froude numbers Fs≡V/gS=1 and 2.5. Here, g is the gravitational acceleration, V and L denote the ship speed and length, and S is the separation di...

Econometric analysis of the changing effects in wind strength and significant wave height on the probability of casualty in shipping.

Science.gov (United States)

Knapp, Sabine; Kumar, Shashi; Sakurada, Yuri; Shen, Jiajun

2011-05-01

This study uses econometric models to measure the effect of significant wave height and wind strength on the probability of casualty and tests whether these effects changed. While both effects are in particular relevant for stability and strength calculations of vessels, it is also helpful for the development of ship construction standards in general to counteract increased risk resulting from changing oceanographic conditions. The authors analyzed a unique dataset of 3.2 million observations from 20,729 individual vessels in the North Atlantic and Arctic regions gathered during the period 1979-2007. The results show that although there is a seasonal pattern in the probability of casualty especially during the winter months, the effect of wind strength and significant wave height do not follow the same seasonal pattern. Additionally, over time, significant wave height shows an increasing effect in January, March, May and October while wind strength shows a decreasing effect, especially in January, March and May. The models can be used to simulate relationships and help understand the relationships. This is of particular interest to naval architects and ship designers as well as multilateral agencies such as the International Maritime Organization (IMO) that establish global standards in ship design and construction. Copyright © 2011 Elsevier Ltd. All rights reserved.

Linear Water Waves

Science.gov (United States)

Kuznetsov, N.; Maz'ya, V.; Vainberg, B.

2002-08-01

This book gives a self-contained and up-to-date account of mathematical results in the linear theory of water waves. The study of waves has many applications, including the prediction of behavior of floating bodies (ships, submarines, tension-leg platforms etc.), the calculation of wave-making resistance in naval architecture, and the description of wave patterns over bottom topography in geophysical hydrodynamics. The first section deals with time-harmonic waves. Three linear boundary value problems serve as the approximate mathematical models for these types of water waves. The next section uses a plethora of mathematical techniques in the investigation of these three problems. The techniques used in the book include integral equations based on Green's functions, various inequalities between the kinetic and potential energy and integral identities which are indispensable for proving the uniqueness theorems. The so-called inverse procedure is applied to constructing examples of non-uniqueness, usually referred to as 'trapped nodes.'

Wave-induced Hydroelastic response of fast monohull ships

DEFF Research Database (Denmark)

Jensen, Jørgen Juncher

1996-01-01

High-speed ships are weight sensitive structures and high strength steel, aluminium or composites are preferred building materials. it is characteristic for these materials that they result in larger hull flexibility than more conventional materials. Therefore, for large fast ships the lowest...... of a quadratic strip theory formulated in the frequency domain. The springing response is thereby excited partly be resonance and partly by non-linear excitation. Special emphasis is given to the influence of springing on fatigue damage as the extreme responses even for very flexible ships are quite insensitive...

Nonlinear rolling of a biased ship in a regular beam wave under external and parametric excitations

Energy Technology Data Exchange (ETDEWEB)

El-Bassiouny, A.F. [Mathematics Dept., Benha Univ., Benha (Egypt)

2007-10-15

We consider a nonlinear oscillator simultaneously excited by external and parametric functions. The oscillator has a bias parameter that breaks the symmetry of the motion. The example that we use to illustrate the problem is the rolling oscillation of a biased ship in longitudinal waves, but many mechanical systems display similar features. The analysis took into consideration linear, quadratic, cubic, quintic, and seven terms in the polynomial expansion of the relative roll angle. The damping moment consists of the linear term associated with radiation and viscous damping and a cubic term due to frictional resistance and eddies behind bilge keels and hard bilge corners. Two methods (the averaging and the multiple time scales) are used to investigate the first-order approximate analytical solution. The modulation equations of the amplitudes and phases are obtained. These equations are used to obtain the stationary state. The stability of the proposed solution is determined applying Liapunov's first method. Effects of different parameters on the system behaviour are investigated numerically. Results are presented graphically and discussed. The results obtained by two methods are in excellent agreement. (orig.)

Radar imagery from the 1994 Lock Linnhe ship wake experiment

Energy Technology Data Exchange (ETDEWEB)

Mullenhoff, C.J.; Lehman, S.K.; Jones, H. [Lawrence Livermore National Lab., CA (United States)] [and others

1994-11-15

The 1994 Loch Linnhe radar ocean imaging trials were held from September 4 through September 17. Two ships were used: the R.V. Colonel Templer, and the RMAS Collie. Thorn EMI, Inc., fielded a dual band, dual polarization radar on a hillside overlooking the loch. A primary purpose of the experiment was to obtain highly visible images of ship generated internal waves. Presented here is imagery for a few of the good ship runs, as well as a study of the environment of the visibility of ship generated internal waves.

Resistive drift wave turbulence and transport

International Nuclear Information System (INIS)

Wakatani, M.

1986-01-01

Our efforts for studying the properties of resistive drift wave turbulence by using model mode-coupling equations are shown. It may be related to the edge turbulence and the associated anomalous transport in tokamaks or in stellarator/heliotron. (author)

Performance Monitoring of Ships

DEFF Research Database (Denmark)

Hansen, Søren Vinther

is used as input to the system and by comparing model and ship behaviour, an index describing the ship’s performance is generated. The work in this thesis is based on data logged through the automation system on board a PostPanmax container ship where data have been logged through a year. A routine...... in the models have been identified. The models used in this work are based on empirical relations or based on regression analyses of model tests and full-scale trials. In order to achieve valid results the conditions where performance is estimated have to be inside the boundaries of the model. Filters have been......The purpose of the research project is to establish a reliable index in the performance evaluation of ships. During operation the ship will experience added resistance due to fouling of hull and propeller. The added resistance will lead to increased fuel consumption and thus increased emissions...

SIMULATION OF SHIP GENERATED TURBULENT AND VORTICAL WAKE IMAGING BY SAR

Institute of Scientific and Technical Information of China (English)

Wang Aiming; Zhu Minhui

2004-01-01

Synthetic Aperture Radar (SAR) imaging of ocean surface features is studied. The simulation of the turbulent and vortical features generated by a moving ship and SAR imaging of these wakes is carried out. The turbulent wake damping the ocean surface capillary waves may be partially responsible for the suppression of surface waves near the ship track. The vortex pair generating a change in the lateral flow field behind the ship may be partially responsible for an enhancement of the waves near the edges of the smooth area. These hydrodynamic phenomena as well as the changes of radar backscatter generated by turbulence and vortex are simulated.An SAR imaging model is then used on such ocean surface features to provide SAR images.Comparison of two ships' simulated SAR images shows that the wake features are different for various ship parameters.

Influence of Variable Acceleration on Parametric Roll Motion of a Container Ship

Directory of Open Access Journals (Sweden)

Emre PEŞMAN

2016-09-01

Full Text Available Ship operators increase or decrease thrust force of ships to avoid parametric roll motion. These operations cause varying acceleration values. In this study, influence of variable acceleration and deceleration of ships on roll motion is investigated in longitudinal waves. The method which is referred as simple model is utilized for analysis. Simple Model is one degree of freedom nonlinear parametric roll motion equation which contains changing velocity and restoring moment in waves with respect to time. Ship velocities in waves are predicted by XFlow software for various thrust forces. Results indicate that variable acceleration has significant effect on parametric roll phenomenon.

Mapping the Qademah Fault with Traveltime, Surface-wave, and Resistivity Tomograms

KAUST Repository

Hanafy, Sherif M.

2015-08-19

Traveltime, surface-wave, and resistivity tomograms are used to track the buried Qademah fault located near King Abdullah Economic City (KAEC), Saudi Arabia. The fault location is confirmed by the 1) resistivity tomogram obtained from an electrical resistivity experiment, 2) the refraction traveltime tomogram, 3) the reflection image computed from 2D seismic data set recorded at the northern part of the fault, and 4) the surface-wave tomogram.

Mapping the Qademah Fault with Traveltime, Surface-wave, and Resistivity Tomograms

KAUST Repository

Hanafy, Sherif M.

2015-01-01

Traveltime, surface-wave, and resistivity tomograms are used to track the buried Qademah fault located near King Abdullah Economic City (KAEC), Saudi Arabia. The fault location is confirmed by the 1) resistivity tomogram obtained from an electrical resistivity experiment, 2) the refraction traveltime tomogram, 3) the reflection image computed from 2D seismic data set recorded at the northern part of the fault, and 4) the surface-wave tomogram.

Towards Predicting the Added Resistance of Slow Ships in Waves

DEFF Research Database (Denmark)

Amini Afshar, Mostafa

been implemented using the Overture framework for solving partial differential equations on overset, boundary-fitted grids. This library includes support for parallel processing and a variety of direct and iterative system solvers. The non-linear water water wave problem is linearised about two base......-surface boundary conditions. The field continuity equation has been discretised by a centered fourth-order finite difference scheme which also includes ghost layers at the boundaries. For the zero-speed hydrodynamic problem, the same centered scheme can be utilised to calculate the free-surface derivatives...... can be applied to the solution after each time step. The filtering scheme can be used with the centered finite difference scheme. Both of these strategies introduce numerical diffusion into the model to ensure the stability in the case of the forward-speed hydrodynamic problems. The developed...

Simulation-Based Analysis of Ship Motions in Short-Crested Irregular Seas

Directory of Open Access Journals (Sweden)

Kıvanç Ali ANIL

2017-03-01

Full Text Available Demonstration of the seakeeping calculation results other than polar diagrams and Cartesian plots is important during the initial and detail design stages of naval platforms due to the necessity of numerical simulations (time series data for the design and validation of the systems on board. These time series simulations are called as “real time computer experiments”. Similar simulation algorithms for ship motions and wave elevation are also used by ship-handling simulators for realistic visualization. The goal of this paper is to create a basis for the simulation-based analysis of ship motions and wave elevation for future design and validation studies for both the naval platform itself and the systems on board. The focus of this paper is the clarification of the theoretical background of this process, i.e. all formulations required to create and validate a ship motion and wave surface simulation are given in detail. The results of this study may also be used in ship-handling simulators or helicopter landing on ship simulations.

Experimental Investigation of the Resistance Performance and Heave and Pitch Motions of Ice-Going Container Ship Under Pack Ice Conditions

Science.gov (United States)

Guo, Chun-yu; Xie, Chang; Zhang, Jin-zhao; Wang, Shuai; Zhao, Da-gang

2018-04-01

In order to analyze the ice-going ship's performance under the pack ice conditions, synthetic ice was introduced into a towing tank. A barrier using floating cylinder in the towing tank was designed to carry out the resistance experiment. The test results indicated that the encountering frequency between the ship model and the pack ice shifts towards a high-velocity point as the concentration of the pack ice increases, and this encountering frequency creates an unstable region of the resistance, and the unstable region shifts to the higher speed with the increasing concentration. The results also showed that for the same speed points, the ratio of the pack ice resistance to the open water resistance increases with the increasing concentration, and for the same concentrations, this ratio decreases as the speed increases. Motion characteristics showed that the mean value of the heave motion increases as the speed increases, and the pitch motion tends to increase with the increasing speed. In addition, the total resistance of the fullscale was predicted.

Global Loads on FRP Ship Hulls

DEFF Research Database (Denmark)

Pedersen, Preben Terndrup

1997-01-01

Fibre reinforced plastic (FRP) composites used for high-speed vessels have lower modulus of elasticity than the conventionally used steels.Therefore, for large fast ships the lowest natural frequencies of the global hull modes can be relatively low compared to the frequency of waveencounter....... As part of the NoKoS project it was decided to investigate the effect of hull flexibility on the wave-induced as well as accidental structural loads on high-speed ships.Especially it was decided to determine whether there is an upper size of FRP and aluminium mono-hulls caused by continuous wave action...

Wave-induced hydroelastic response of fast monohull displacement ships

DEFF Research Database (Denmark)

Jensen, Jørgen Juncher; Wang, Zhaohui

1998-01-01

High-speed ships are weight sensitive structures and high strength steel, aluminium or composites are preferred building materials. It is characteristic for these materials that they result in larger hull flexibility than more conventional materials. Therefore, for large fast ships the lowest...

Waves from Propulsion Systems of Fast Ferries

DEFF Research Database (Denmark)

Taatø, Søren Haugsted; Aage, Christian; Arnskov, Michael M.

1998-01-01

Waves from fast ferries have become an environmental problem of growing concern to the public. Fast ferries produce not only higher waves than conventional ships but also fundamentally different wave systems when they sail at supercritical speeds. Hitherto, ship waves have been considered as being...... generated by the ship hulls alone. Whereas this assumption may be reasonable for conventional ships with large hulls and limited propulsive power, the situation is different for fast ferries with their smaller hulls and very large installed power. A simple theoretical model and a series of model tests...... on a monohull fast ferry seem to indicate that a substantial part of the wave-making can be directly attributed to the propulsion system itself. Thus, two wave systems are created with different phases, but with similar frequency contents, which means that they merge into one system behind the ship, very...

Discriminations of critical conditions of a high speed ship in quarterings sea waves by using tools of the sea state determinations by GMS. Eisei joho kaisho settei shien tool ni motozuku chokosokusen no shatsuiha rinkai jotai no hanmei

Energy Technology Data Exchange (ETDEWEB)

Yamaguchi, S.; +Ishida, T. (Kyushu University, Fukuoka (Japan)); Shinkai, A. (Kyushu University, Fukuoka (Japan). Faculty of Engineering)

1991-09-04

The documentation assumes a new type high speed ship, higher than 50kt in speed and heavier than 1000ton in dead weight, to require the ocean goingness, middle distance navigation and high speed transport. The present report dealed with how to discriminate a ship, navigating at a high speed on oceanic waves, in critical condition against the encountering waves. Navigating far distantly from the shore, the ship was generally made to positively utilize the information data from the geostationary metheorological satellite (GMS) to be applied as a support soft tool for the maritime system and other designs. As a result, the high speed ship on the quartering waves was numerically elucidated in critical condition against the encountering waves and simultaneously assumed in critical course upon discriminating the critical condition in a concretely designated oceanic area. It was shown that, if different Froude numbers are calculated and ordered of critical circular frequency, angle, wave period, etc. against the encountering, a dimensionally arbitrary ship is easily discriminatable in critical course in an arbitrary oceanic area by utilizing a GMS determination support tool. 12 refs., 14 figs., 2 tabs.

A Fully Nonlinear, Dynamically Consistent Numerical Model for Solid-Body Ship Motion. I. Ship Motion with Fixed Heading

Science.gov (United States)

Lin, Ray-Quing; Kuang, Weijia

2011-01-01

In this paper, we describe the details of our numerical model for simulating ship solidbody motion in a given environment. In this model, the fully nonlinear dynamical equations governing the time-varying solid-body ship motion under the forces arising from ship wave interactions are solved with given initial conditions. The net force and moment (torque) on the ship body are directly calculated via integration of the hydrodynamic pressure over the wetted surface and the buoyancy effect from the underwater volume of the actual ship hull with a hybrid finite-difference/finite-element method. Neither empirical nor free parametrization is introduced in this model, i.e. no a priori experimental data are needed for modelling. This model is benchmarked with many experiments of various ship hulls for heave, roll and pitch motion. In addition to the benchmark cases, numerical experiments are also carried out for strongly nonlinear ship motion with a fixed heading. These new cases demonstrate clearly the importance of nonlinearities in ship motion modelling.

Ship Roll Damping Control

DEFF Research Database (Denmark)

Perez, Tristan; Blanke, Mogens

2012-01-01

limitations and large variations of the spectral characteristics of wave-induced roll motion. This tutorial paper presents an account of the development of various ship roll motion control systems together with the challenges associated with their design. It discusses the assessment of performance...

Development of the Nuclear Ship Database. 1. Outline of the Nuclear Ship Experimental Database

Energy Technology Data Exchange (ETDEWEB)

Kyouya, Masahiko; Ochiai, Masa-aki [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Hashidate, Kouji

1995-03-01

We obtained the experimental data on the effects of the ship motions and the change in load and caused by the ship operations, the waves, the winds etc., to the nuclear power plant behavior, through the Power-up Tests and Experimental Voyages of the Nuclear Ship MUTSU. Moreover, we accumulated the techniques, the knowledge and others on the Nuclear Ship development at the each stage of the N.S. MUTSU Research and Development program, such as the design stage, the construction stage, the operation stage and others. These data, techniques, knowledge and others are the assembly of the experimental data and the experiences through the design, the construction and the operation of the first nuclear ship in JAPAN. It is important to keep and pigeonhole these products of the N.S. MUTSU program in order to utilize them effectively in the research and development of the advanced marine reactor, since there is no construction plan of the nuclear ship for the present in JAPAN. We have been carrying out the development of the Nuclear Ship Database System since 1991 for the purpose of effective utilization of the N.S. MUTSU products in the design study of the advanced marine reactors. The part of the Nuclear Ship Database System on the experimental data, called Nuclear Ship Experimental Database, was already accomplished and utilized since 1993. This report describes the outline and the use of the Nuclear Ship Experimental Database.The remaining part of the database system on the documentary data, called Nuclear Ship Documentary Database, are now under development. (author).

Development of the Nuclear Ship Database. 1. Outline of the Nuclear Ship Experimental Database

International Nuclear Information System (INIS)

Kyouya, Masahiko; Ochiai, Masa-aki; Hashidate, Kouji.

1995-03-01

We obtained the experimental data on the effects of the ship motions and the change in load and caused by the ship operations, the waves, the winds etc., to the nuclear power plant behavior, through the Power-up Tests and Experimental Voyages of the Nuclear Ship MUTSU. Moreover, we accumulated the techniques, the knowledge and others on the Nuclear Ship development at the each stage of the N.S. MUTSU Research and Development program, such as the design stage, the construction stage, the operation stage and others. These data, techniques, knowledge and others are the assembly of the experimental data and the experiences through the design, the construction and the operation of the first nuclear ship in JAPAN. It is important to keep and pigeonhole these products of the N.S. MUTSU program in order to utilize them effectively in the research and development of the advanced marine reactor, since there is no construction plan of the nuclear ship for the present in JAPAN. We have been carrying out the development of the Nuclear Ship Database System since 1991 for the purpose of effective utilization of the N.S. MUTSU products in the design study of the advanced marine reactors. The part of the Nuclear Ship Database System on the experimental data, called Nuclear Ship Experimental Database, was already accomplished and utilized since 1993. This report describes the outline and the use of the Nuclear Ship Experimental Database.The remaining part of the database system on the documentary data, called Nuclear Ship Documentary Database, are now under development. (author)

Hydroelastic Vibrations of Ships

DEFF Research Database (Denmark)

Jensen, Jørgen Juncher; Folsø, Rasmus

2002-01-01

A formula for the necessary hull girder bending stiffness required to avoid serious springing vibrations is derived. The expression takes into account the zero crossing period of the waves, the ship speed and main dimensions. For whipping vibrations the probability of exceedance for the combined...

Full Scale Measurements of the Hydro-Elastic Response of Large Container Ships for Decision Support

DEFF Research Database (Denmark)

Andersen, Ingrid Marie Vincent

scale measurements from four container ships of 4,400 TEU, 8,600 TEU, 9,400 TEU and 14,000 TEU Primarily, strains measured near the deck amidships are used. Furthermore, measurements of motions and the encountered sea state are available for one of the ships. The smallest ship is in operation...... frequency with the waves. Together with the relatively high design speed and often pronounced bow flare this makes large container ship more sensitive to slamming and, consequently, the effects of wave-induced hull girder vibrations. From full scale strain measurements of individual, measured hull girder......The overall topic of this thesis is decision support for operation of ships and several aspects are covered herein. However, the main focus is on the wave-induced hydro-elastic response of large container ships and its implications on the structural response. The analyses are based mainly on full...

Time-domain hybrid method for simulating large amplitude motions of ships advancing in waves

Directory of Open Access Journals (Sweden)

Shukui Liu

2011-03-01

Full Text Available Typical results obtained by a newly developed, nonlinear time domain hybrid method for simulating large amplitude motions of ships advancing with constant forward speed in waves are presented. The method is hybrid in the way of combining a time-domain transient Green function method and a Rankine source method. The present approach employs a simple double integration algorithm with respect to time to simulate the free-surface boundary condition. During the simulation, the diffraction and radiation forces are computed by pressure integration over the mean wetted surface, whereas the incident wave and hydrostatic restoring forces/moments are calculated on the instantaneously wetted surface of the hull. Typical numerical results of application of the method to the seakeeping performance of a standard containership, namely the ITTC S175, are herein presented. Comparisons have been made between the results from the present method, the frequency domain 3D panel method (NEWDRIFT of NTUA-SDL and available experimental data and good agreement has been observed for all studied cases between the results of the present method and comparable other data.

Plastic Pollution from Ships

OpenAIRE

Čulin, Jelena; Bielić, Toni

2016-01-01

The environmental impact of shipping on marine environment includes discharge of garbage. Plastic litter is of particular concern due to abundance, resistance to degradation and detrimental effect on marine biota. According to recently published studies, a further research is required to assess human health risk. Monitoring data indicate that despite banning plastic disposal at sea, shipping is still a source of plastic pollution. Some of the measures to combat the problem are discussed.

Design methods to assess the resistance of Offshore wind Turbine Structures impacted by a ship

OpenAIRE

Echeverry Jaramillo, Sara; Le Sourne, Hervé; Bela, Andreea; Pire, Timothée; Rigo, Philippe

2017-01-01

The dynamic modes of jacket, monopile and Floating offshore wind turbines (FOWT) after a collision event are presented. The authors have developed simplified analytical formulations based on plastic limit analysis to assess the resistance of an offshore wind turbine jacket impacted by a ship. For the case of collisions with monopile foundations and FOWT, the crushing behavior and structure dynamics are studied by means of finite element simulations. Numerical results for both monopile and flo...

Experimental investigation of frictional resistance reduction with air layer on the hull bottom of a ship

Directory of Open Access Journals (Sweden)

Jang Jinho

2014-06-01

Full Text Available In an effort to cope with recent high oil price and global warming, developments of air lubricated ships have been pursued to reduce greenhouse gas emissions and to save fuel costs by reducing the frictional resistance. In this study, reduction in the frictional resistance by air lubrication with air layers generated on the lower surface of a flat plate was investigated experimentally in the large water tunnel of SSMB. The generated air layers were observed, and changes in the local frictional drag were measured at various flow rates of injected air. The results indicated that air lubrication with air layers might be useful in reducing the frictional resistance at specific conditions of air injection. Accordingly, resistance and self-propulsion tests for a 66K DWT bulk carrier were carried out in the towing tank of SSMB to estimate the expected net power savings.

Extreme value prediction of the wave-induced vertical bending moment in large container ships

DEFF Research Database (Denmark)

Andersen, Ingrid Marie Vincent; Jensen, Jørgen Juncher

2015-01-01

increase the extreme hull girder response significantly. Focus in the present paper is on the influence of the hull girder flexibility on the extreme response amidships, namely the wave-induced vertical bending moment (VBM) in hogging, and the prediction of the extreme value of the same. The analysis...... in the present paper is based on time series of full scale measurements from three large container ships of 8600, 9400 and 14000 TEU. When carrying out the extreme value estimation the peak-over-threshold (POT) method combined with an appropriate extreme value distribution is applied. The choice of a proper...... threshold level as well as the statistical correlation between clustered peaks influence the extreme value prediction and are taken into consideration in the present paper....

A Direct and Fast Methodology for Ship Recognition in Sentinel-2 Multispectral Imagery

Directory of Open Access Journals (Sweden)

Henning Heiselberg

2016-12-01

Full Text Available The European Space Agency satellite Sentinel-2 provides multispectral images with pixel sizes down to 10 m. This high resolution allows for ship detection and recognition by determining a number of important ship parameters. We are able to show how a ship position, its heading, length and breadth can be determined down to a subpixel resolution. If the ship is moving, its velocity can also be determined from its Kelvin waves. The 13 spectrally different visual and infrared images taken using multispectral imagery (MSI are “fingerprints” that allow for the recognition and identification of ships. Furthermore, the multispectral image profiles along the ship allow for discrimination between the ship, its turbulent wakes, and the Kelvin waves, such that the ship’s length and breadth can be determined more accurately even when sailing. The ship’s parameters are determined by using satellite imagery taken from several ships, which are then compared to known values from the automatic identification system. The agreement is on the order of the pixel resolution or better.

Investigation of hydroelastic ship responses of an ULOC in head seas

Science.gov (United States)

Wang, Xue-liang; Temarel, Pandeli; Hu, Jia-jun; Gu, Xue-kang

2016-10-01

Investigation of hydroelastic ship responses has been brought to the attention of the scientific and engineering world for several decades. There are two kinds of high-frequency vibrations in general ship responses to a large ocean-going ship in its shipping line, so-called springing and whipping, which are important for the determination of design wave load and fatigue damage as well. Because of the huge scale of an ultra large ore carrier (ULOC), it will suffer seldom slamming events in the ocean. The resonance vibration with high frequency is springing, which is caused by continuous wave excitation. In this paper, the wave-induced vibrations of the ULOC are addressed by experimental and numerical methods according to 2D and 3D hydroelasticity theories and an elastic model under full-load and ballast conditions. The influence of loading conditions on high-frequency vibration is studied both by numerical and experimental results. Wave-induced vibrations are higher under ballast condition including the wave frequency part, the multiple frequencies part, the 2-node and the 3-node vertical bending parts of the hydroelastic responses. The predicted results from the 2D method have less accuracy than the 3D method especially under ballast condition because of the slender-body assumption in the former method. The applicability of the 2D method and the further development of nonlinear effects to 3D method in the prediction of hydroelastic responses of the ULOC are discussed.

Improved Wave-vessel Transfer Functions by Uncertainty Modelling

DEFF Research Database (Denmark)

Nielsen, Ulrik Dam; Fønss Bach, Kasper; Iseki, Toshio

2016-01-01

This paper deals with uncertainty modelling of wave-vessel transfer functions used to calculate or predict wave-induced responses of a ship in a seaway. Although transfer functions, in theory, can be calculated to exactly reflect the behaviour of the ship when exposed to waves, uncertainty in inp...

Linear waves in a resistive plasma with Hall current

International Nuclear Information System (INIS)

Almaguer, J.A.

1992-01-01

Dispersion relations for the case of a magnetized plasma are determined taking into account the Hall current and a constant resistivity, η, in Ohm's law. It is found that the Hall effect is relevant only for parallel (to the equilibrium magnetic field) wave numbers in the case of uniform plasmas, giving place to a dispersive behavior. In particular, the cases of η→0 and small (nonzero) resistivity are discussed

Resistance test of high-speed ship by means of attitude control method. Part 2; Shisei seigyo hoshiki ni yoru kosokutei no teiko shiken. 2

Energy Technology Data Exchange (ETDEWEB)

Hayashida, S [Nagasaki Institute of Applied Science, Nagasaki (Japan)

1996-04-10

The previous paper has proposed a resistance test method by controlling the attitude of a high-speed model ship using a personal computer without making a data base. For this method, the fluid force acting on the hull of model ship is measured, to change its attitude based on the measurement, and then, the fluid force is measured again, to change the attitude again. The traveling attitude is created by repeating this, to measure the force acting on the hull. Since the attitude is changed by calculating using the fluid force measured, various factors can be considered in the calculation process. For example, a test with an arbitrary displacement in an arbitrary position of center of gravity can be conducted in spite of actual displacement and position of center of gravity of the model ship. A test for a high-speed ship was conducted through this method, to obtain nearly satisfactory results compared with a usual resistance test. Occasionally, a lot of repetitions were required to satisfy the balancing condition of the force. In this study, the improvement of testing efficiency has been planned by modifying the analyzing program. 5 refs., 7 figs., 1 tab.

Numerical analysis of viscous effect on ship rolling motions based on CFD

Directory of Open Access Journals (Sweden)

LUO Tian

2017-03-01

Full Text Available During the ship design procedure, the analysis of ship rolling motions is of great significance because the rolling motions have extraordinary effects on the sea-keeping, maneuverability and stability of a ship. It is difficult to simulate rolling motions due to the effect of viscosity, which causes many nonlinear components in computation. As such, the potential theory used for other ship motions cannot be used for rolling motions. This paper simulates the rolling motions of the DTMB 5512 ship model and the ship transverse section of the S60 ship model with a naoe-FOAM-SJTU solver using the Reynolds Averaged Navier Stokes(RANSmethod based on the OpenFOAM. The results of rolling motions are compared with the experimental data, which confirms the reliability of the meshes and results. For the ship transverse section of the S60 ship model, the damping coefficient is divided into three parts with the Euler and RANS methods:friction, vorticity and wave parts. For the DTMB 5512 ship model, the damping coefficient is also respectively analyzed, including the friction, vorticity, wave and bilge keel parts. The results in this paper show that the vorticity part accounts for the greatest proportion, while the friction part accounts for the least, and the bilge keels reduces the damping moment to a certain extent which shows the effect of rolling parameters on rolling motions and moments.

THE BEHAVIOR OF TRANSVERSE WAVES IN NONUNIFORM SOLAR FLUX TUBES. I. COMPARISON OF IDEAL AND RESISTIVE RESULTS

International Nuclear Information System (INIS)

Soler, Roberto; Terradas, Jaume; Oliver, Ramón; Goossens, Marcel

2013-01-01

Magnetohydrodynamic (MHD) waves are ubiquitously observed in the solar atmosphere. Kink waves are a type of transverse MHD waves in magnetic flux tubes that are damped due to resonant absorption. The theoretical study of kink MHD waves in solar flux tubes is usually based on the simplification that the transverse variation of density is confined to a nonuniform layer much thinner than the radius of the tube, i.e., the so-called thin boundary approximation. Here, we develop a general analytic method to compute the dispersion relation and the eigenfunctions of ideal MHD waves in pressureless flux tubes with transversely nonuniform layers of arbitrary thickness. Results for kink waves are produced and compared with fully numerical resistive MHD eigenvalue computations in the limit of small resistivity. We find that the frequency and resonant damping rate are the same in both ideal and resistive cases. The actual results for thick nonuniform layers deviate from the behavior predicted in the thin boundary approximation and strongly depend on the shape of the nonuniform layer. The eigenfunctions in ideal MHD are very different from those in resistive MHD. The ideal eigenfunctions display a global character regardless of the thickness of the nonuniform layer, while the resistive eigenfunctions are localized around the resonance and are indistinguishable from those of ordinary resistive Alfvén modes. Consequently, the spatial distribution of wave energy in the ideal and resistive cases is dramatically different. This poses a fundamental theoretical problem with clear observational consequences

Towards fault-tolerant decision support systems for ship operator guidance

DEFF Research Database (Denmark)

Nielsen, Ulrik Dam; Lajic, Zoran; Jensen, Jørgen Juncher

2012-01-01

Fault detection and isolation are very important elements in the design of fault-tolerant decision support systems for ship operator guidance. This study outlines remedies that can be applied for fault diagnosis, when the ship responses are assumed to be linear in the wave excitation. A novel num...

Crushing of ship bows in head-on collision

DEFF Research Database (Denmark)

Ocakli, H.; Zhang, S.; Pedersen, Preben Terndrup

2004-01-01

Semi-analytical methods for analysis of plate crushing and ship bow damage in head-on collisions are developed in this paper. Existing experimental and theoretical studies for crushing analysis of plated structures are summarized and compared. Simple formulae for determining the crushing force....... The approach developed can be used easily to determine the crushing resistance and damage extent of the ship bow when ship length and collision speed are known. The method can be used in probabilistic analysis of damage extents in ship collisions where a large number of calculations are generally required....

Development of ship structure health monitoring system based on IOT technology

Science.gov (United States)

Yang, Sujun; Shi, Lei; Chen, Demin; Dong, Yuqing; Hu, Zhenyi

2017-06-01

It is very important to monitor the ship structure, because ships are affected by all kinds of wind wave and current environment factor. At the same time, internet of things (IOT) technology plays more and more important role of in the development of industrial process. In the paper, real-time online monitoring of the ship can be realized by means of IOT technology. Ship stress, vibration and dynamic parameters are measured. Meanwhile, data is transmitted to remote monitoring system through intelligent data gateway. Timely remote support can be realized for dangerous stage of ship. Safe navigation of ships is guaranteed through application of the system.

Influences of the separation distance, ship speed and channel dimension on ship maneuverability in a confined waterway

Science.gov (United States)

Du, Peng; Ouahsine, Abdellatif; Sergent, Philippe

2018-05-01

Ship maneuvering in the confined inland waterway is investigated using the system-based method, where a nonlinear transient hydrodynamic model is adopted and confinement models are implemented to account for the influence of the channel bank and bottom. The maneuvering model is validated using the turning circle test, and the confinement model is validated using the experimental data. The separation distance, ship speed, and channel width are then varied to investigate their influences on ship maneuverability. With smaller separation distances and higher speeds near the bank, the ship's trajectory deviates more from the original course and the bow is repelled with a larger yaw angle, which increase the difficulty of maneuvering. Smaller channel widths induce higher advancing resistances on the ship. The minimum distance to the bank are extracted and studied. It is suggested to navigate the ship in the middle of the channel and with a reasonable speed in the restricted waterway.

Friction correction for model ship resistance and propulsion tests in ice at NRC's OCRE-RC

Directory of Open Access Journals (Sweden)

Michael Lau

2018-05-01

Full Text Available This paper documents the result of a preliminary analysis on the influence of hull-ice friction coefficient on model resistance and power predictions and their correlation to full-scale measurements. The study is based on previous model-scale/full-scale correlations performed on the National Research Council - Ocean, Coastal, and River Engineering Research Center's (NRC/OCRE-RC model test data. There are two objectives for the current study: (1 to validate NRC/OCRE-RC's modeling standards in regarding to its practice of specifying a CFC (Correlation Friction Coefficient of 0.05 for all its ship models; and (2 to develop a correction methodology for its resistance and propulsion predictions when the model is prepared with an ice friction coefficient slightly deviated from the CFC of 0.05. The mean CFC of 0.056 and 0.050 for perfect correlation as computed from the resistance and power analysis, respectively, have justified NRC/OCRE-RC's selection of 0.05 for the CFC of all its models. Furthermore, a procedure for minor friction corrections is developed. Keywords: Model test, Ice resistance, Power, Friction correction, Correlation friction coefficient

Load and Global Response of Ships

DEFF Research Database (Denmark)

Jensen, Jørgen Juncher

The present monograph covers wave load and global structural response for ships. It is primary written as a textbook for students with an introductionary background in naval architecture and a basic knowledge of statistics and strength of materials. The subjects are treated in details starting from...... first principles. The aim has been to derive and present the necessary theoretical framework for predicting the extreme loads and the corresponding hull girder stresses the ship may be subjected to during its operational lifetime.Although some account is given to reliabiity analysis, the present...

Wave spectra, meteorological, and other data from NOAA Ship FERREL and other platforms from the Chesapeake Bay from 1983-03-14 to 1983-11-22 (NODC Accession 8500124)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Wave spectra, meteorological, and other data were collected from NOAA Ship FERREL and other platforms in the Chesapeake Bay. Data were collected by the National...

Testing fire resistant boom in waves and flames

International Nuclear Information System (INIS)

McCourt, J.; Buist, I.; Pratte, B.; Jamieson, W.; Mullin, J.

1997-01-01

A near full-scale screening test to evaluate the durability and ability of refractory-fabric fire resistant booms to contain oil during an in-situ burn without the environmental problems of burning crude oil or the cost of testing offshore, was developed. The boom was first flexed under tension for two hours, then deployed in a U-configuration in an outdoor wave tank. Propane gas was burned in the pocket of the boom to simulate the collection and burning phases of an in-situ burn. Finally, the boom was returned to the indoor wave flume for another two hours of wave action and then inspected for damage. Results indicated damage of the same type as suffered in previously conducted sea trials, although the extent of damage was less severe. These results led to recommendations for improvement of the test protocol which included: (1) increasing the heat flux to the boom, (2) improving the heat flux measurement, (3) increasing the tension in the fire boom during flame testing, and (4) improving the characterization of the waves near the fire boom. 16 refs., 6 figs

Review of ship slamming loads and responses

Science.gov (United States)

Wang, Shan; Guedes Soares, C.

2017-12-01

The paper presents an overview of studies of slamming on ship structures. This work focuses on the hull slamming, which is one of the most important types of slamming problems to be considered in the ship design process and the assessment of the ship safety. There are three main research aspects related to the hull slamming phenomenon, a) where and how often a slamming event occurs, b) slamming load prediction and c) structural response due to slamming loads. The approaches used in each aspect are reviewed and commented, together with the presentation of some typical results. The methodology, which combines the seakeeping analysis and slamming load prediction, is discussed for the global analysis of the hull slamming of a ship in waves. Some physical phenomena during the slamming event are discussed also. Recommendations for the future research and developments are made.

The wave buoy analogy - estimating high-frequency wave excitations

DEFF Research Database (Denmark)

Nielsen, Ulrik Dam

2008-01-01

of sea state parameters — influence of filtering. Ocean Engineering 2007;34:1797–810.], where time series of ship responses were generated from a known wave spectrum for the purpose of the inverse process — the estimation of the underlying wave excitations. Similar response generations and vice versa...

Comparisons of Means for Estimating Sea States from an Advancing Large Container Ship

DEFF Research Database (Denmark)

Nielsen, Ulrik Dam; Andersen, Ingrid Marie Vincent; Koning, Jos

2013-01-01

to ship-wave interactions in a seaway. In the paper, sea state estimates are produced by three means: the wave buoy analogy, relying on shipboard response measurements, a wave radar system, and a system providing the instantaneous wave height. The presented results show that for the given data, recorded...

High-spatial resolution resistivity mapping of large-area YBCO films by a near-field millimeter-wave microscope

International Nuclear Information System (INIS)

Golosovsky, M.; Galkin, A.; Davidov, D.

1996-01-01

The authors demonstrate a new millimeter-wave technique for the resistivity mapping of large-area conducting films, namely, a near-field resistivity microscope. The microscope is based on the idea that electromagnetic waves are transmitted through a narrow resonant slit with high efficiency. By scanning this slit at fixed height above an inhomogeneous conducting surface and measuring the intensity and phase of the reflected wave, the resistivity of this surface may be determined with a 10--100 microm spatial resolution using 80-GHz radiation. Using this technique, they map normal-sate resistivity of 1 in x 1 in YBCO films at ambient temperature. In some films they find inhomogeneities of the normal-state sheet resistance of the order of 10%--20%

Effect of passing vessels on a moored ship

Energy Technology Data Exchange (ETDEWEB)

Lean, G H; Price, W A

1977-11-01

The effect of passing vessels on a moored ship was investigated by a series of model tests carried out at the Hydraulics Research Station for the Esso Petroleum Co. Ltd., transportation department in connection with their oil jetty at Milford Haven. A main conclusion was that the forces appeared to be due to the pressure gradients associated with the pattern of flow that accompanies the passing ship rather than with the wave system. Slack lines are to be avoided, and some relief in maximum line loads can be achieved by increasing the pretension. The results included the effects of passing vessel speed and ship clearance and draft.

Structural analysis of a ship on global aspect using ANSYS

Science.gov (United States)

Rahman, M. Muzibur; Kamol, Rajia Sultana; Islam, Reyana

2017-12-01

Ship is a complex geometry which undergoes a combination of loadings such as hydrostatic, hydrodynamic, wind, wave etc. at sea and thus adequate strength in a ship has always been one of the most challenging tasks for the ship designers. International Maritime Organization (IMO) and classification societies are providing the standards to ensure the adequacy of strength for the ship against all demands throughout its service life. Thus, structural analysis is needed to assess the overall strength of hull, and the means in this regard are based on finite element method which may be applied either local or global aspect of the ship. This paper is an attempt to carry out the structural analysis of a ship in global aspect using ANSYS software to locate the most stress concentration and deformed area, which will have ultimate effect on fatigue fracture.

Resistive effects on helicity-wave current drive generated by Alfven waves in tokamak plasmas

International Nuclear Information System (INIS)

Bruma, C.; Cuperman, S.; Komoshvili, K.

1997-01-01

This work is concerned with the investigation of non-ideal (resistive) MHD effects on the excitation of Alfven waves by externally launched fast-mode waves, in simulated tokamak plasmas; both continuum range, CR ({ω Alf (r)} min Alf (r)} max ) and discrete range, DR, where global Alfven eigenmodes, GAEs (ω Alf (r)} min ) exist, are considered. (Here, ω Alf (r) ≡ ω Alf [n(r), B 0 (r)] is an eigenfrequency of the shear Alfven wave). For this, a cylindrical current carrying plasma surrounded by a helical sheet-current antenna and situated inside a perfectly conducting shell is used. Toroidicity effects are simulated by adopting for the axial equilibrium magnetic field component a suitable radial profile; shear and finite relative poloidal magnetic field are properly accounted for. A dielectric tensor appropriate to the physical conditions considered in this paper is derived and presented. (author)

Dynamics of skyrmions and edge states in the resistive regime of mesoscopic p-wave superconductors

Energy Technology Data Exchange (ETDEWEB)

Fernández Becerra, V., E-mail: VictorLeonardo.FernandezBecerra@uantwerpen.be; Milošević, M.V., E-mail: milorad.milosevic@uantwerpen.be

2017-02-15

Highlights: • Voltage–current characterization of a mesoscopic p-wave superconducting sample. • Skyrmions and edge states are stabilized with an out-of-plane applied magnetic field. • In the resistive regime, moving skyrmions and the edge state behave distinctly different from the conventional kinematic vortices. - Abstract: In a mesoscopic sample of a chiral p-wave superconductor, novel states comprising skyrmions and edge states have been stabilized in out-of-plane applied magnetic field. Using the time-dependent Ginzburg–Landau equations we shed light on the dynamic response of such states to an external applied current. Three different regimes are obtained, namely, the superconducting (stationary), resistive (non-stationary) and normal regime, similarly to conventional s-wave superconductors. However, in the resistive regime and depending on the external current, we found that moving skyrmions and the edge state behave distinctly different from the conventional kinematic vortex, thereby providing new fingerprints for identification of p-wave superconductivity.

Acute resistance exercise using free weights on aortic wave reflection characteristics.

Science.gov (United States)

Tai, Yu Lun; Gerhart, Hayden; Mayo, Xián; Kingsley, J Derek

2018-01-01

Aortic wave reflection characteristics such as the augmentation index (AIx), wasted left ventricular pressure energy (ΔE w ) and aortic haemodynamics, such as aortic systolic blood pressure (ASBP), strongly predict cardiovascular events. The effects of acute resistance exercise (ARE) using free-weight exercises on these characteristics are unknown. Therefore, we sought to determine the effects of acute free-weight resistance exercise on aortic wave reflection characteristics and aortic haemodynamics in resistance-trained individuals. Fifteen young, healthy resistance-trained (9 ± 3 years) individuals performed two randomized sessions consisting of an acute bout of free-weight resistance exercise (ARE) or a quiet control (CON). The ARE consisted of three sets of 10 repetitions at 75% one repetition maximum for squat, bench press and deadlift. In CON, the participants rested in the supine position for 30 min. Measurements were made at baseline before sessions and 10 min after sessions. A two-way ANOVA was used to compare the effects of condition across time. There were no significant interactions for aortic or brachial blood pressures. Compared to rest, there were significant increases in augmentation pressure (rest: 5·7 ± 3·0 mmHg; recovery: 10·4 ± 5·7 mmHg, P = 0·002), AIx (rest: 116·8 ± 4·2%; recovery: 123·2 ± 8·4%, P = 0·002), AIx normalized at 75 bpm (rest: 5·2 ± 7·6%; recovery: 27·3 ± 13·2%, Pfree-weight exercises may have no effect on aortic and brachial blood pressure but may significantly alter aortic wave reflection characteristics. © 2016 Scandinavian Society of Clinical Physiology and Nuclear Medicine. Published by John Wiley & Sons Ltd.

Nonlinear analysis for a ship with a general roll-damping model

Energy Technology Data Exchange (ETDEWEB)

El-Bassiouny, A F [Mathematics Department, Faculty of Science, Benha University, Benha 13518 (Egypt)

2007-05-15

The qualitative behaviour of the response of a ship rolling in longitudinal waves whose amplitude or frequency (parameters) are slowly varied is presented. An analytical and numerical technique is used to predict the qualitative change taking place in the stable solutions of a ship model as one of the parameters is slowly changed. The analysis took into consideration linear, cubic and quantic terms in the polynomial expansion of the relative roll angle. The damping moment consists of the linear term associated with radiation and viscous damping and a cubic term due to frictional resistance and eddies behind bilge keels and hard bilge corners. Two methods (the averaging and the multiple time scales) are used to investigate a first-order approximate analytical solution. The modulation equations of the amplitudes and phases are obtained. These equations are used to determine steady state solutions. Numerical calculations are presented which illustrate the behaviour of the steady state response amplitude as a function of the detuning parameter. The stability of the proposed solution is determined applying Liapunov's first method. The effects of different parameters on the system behaviour are investigated numerically. The results obtained by the two methods are in excellent agreement.

Construction strength analysis of landing craft tank conversion to passenger ship using finite element method

Science.gov (United States)

Nurul Misbah, Mohammad; Setyawan, Dony; Murti Dananjaya, Wisnu

2018-03-01

This research aims to determine the longitudinal strength of passenger ship which was converted from Landing Craft Tank with 54 m of length as stated by BKI (Biro Klasifikasi Indonesia / Indonesian Classification Bureau). Verification of strength value is done to 4 (four) loading conditions which are (1) empty load condition during sagging wave, (2) empty load condition during hogging wave, (3) full load condition during sagging wave and (4) full load condition during hogging wave. Analysis is done using Finite Element Analysis (FEA) software by modeling the entire part of passenger ship and its loading condition. The back and upfront part of ship centerline were used as the boundary condition. From that analysis it can be concluded that the maximum stress for load condition (1) is 72,393 MPa, 74,792 MPa for load condition (2), 129,92 MPa for load condition (3), and 132,4 MPa for load condition (4). Longitudinal strength of passenger ship fulfilled the criteria of empty load condition having smaller stress value than allowable stress which is 90 MPa, and during full load condition with smaller stress value than allowable stress which is 150 MPa. Analysis on longitudinal strength comparison with entire ship plate thickness variation of ± 2 mm from initial plate was also done during this research. From this research it can be concluded that plate thickness reduction causes the value of longitudinal strength to decrease, while plate thickness addition causes the value of longitudinal strength to increase.

Early Detection of Parametric Roll Resonance on Container Ships

DEFF Research Database (Denmark)

Galeazzi, Roberto; Blanke, Mogens; Poulsen, Niels Kjølstad

2013-01-01

Parametric roll resonance on ships is a nonlinear phenomenon where waves encountered at twice the natural roll frequency can bring the vessel dynamics into a bifurcation mode and lead to extreme values of roll. Recent years have seen several incidents with dramatic damage to container vessels...... the ship's speed and course, to escape from the bifurcation condition. This paper proposes nonparametric methods to detect the onset of roll resonance and demonstrates their performance. Theoretical conditions for parametric resonance are revisited and are used to develop efficient methods to detect its...... on experimental data from model tests and on data from a container ship crossing the Atlantic during a storm....

Pandemic serotypes of Vibrio cholerae isolated from ships' ballast tanks and coastal waters: assessment of antibiotic resistance and virulence genes (tcpA and ctxA).

Science.gov (United States)

Dobbs, Fred C; Goodrich, Amanda L; Thomson, Frank K; Hynes, Wayne

2013-05-01

There is concern that ships' ballasting operations may disseminate Vibrio cholerae to ports throughout the world. Given evidence that the bacterium is indeed transported by ships, we isolated pandemic serotypes O1 and O139 from ballast tanks and characterized them with respect to antibiotic resistance and virulence genes ctxA and tcpA. We carried out concurrent studies with V. cholerae isolated from coastal waters. Of 284 isolates, 30 were serotype O1 and 59 were serotype O139. These serotypes were overrepresented in ballast tanks relative to the coastal waters sampled. All locations, whether coastal waters or ballast tanks, yielded samples from which serotype O1, O139, or both were isolated. There were three groups among the 62 isolates for which antibiotic characterization was conclusive: those exhibiting β-lactamase activity and resistance to at least one of the 12 antibiotics tested; those negative for β-lactamase but having antibiotic resistance; those negative for β-lactamase and registering no antibiotic resistance. When present, antibiotic resistance in nearly all cases was to ampicillin; resistance to multiple antibiotics was uncommon. PCR assays revealed that none of the isolates contained the ctxA gene and only two isolates, one O139 and one O1, contained the tcpA gene; both isolates originated from ballast water. These results support the bacteriological regulations proposed by the International Maritime Association for discharged ballast water.

The destructive impact of the rogue waves

Science.gov (United States)

Shamin, Roman

2013-04-01

In our talk rogue waves at the ocean will be considered. By means of numerical modeling dangerous impact of rogue waves on the ships and oil rigs is calculated. Cases when these waves can bring in accident are considered. Using statistics of emergence of waves (see [1]-[2]), it is possible to estimate risks in each case. These results can be used for safety of the ships and oil rigs from rogue waves. References [1] V.E. Zakharov, A.I. Dyachenko, R.V. Shamin. How probability for freak wave formation can be found // THE EUROPEAN PHYSICAL JOURNAL - SPECIAL TOPICS Volume 185, Number 1, 113-124, DOI: 10.1140/epjst/e2010-01242-y [2] V.E. Zakharov, R.V. Shamin. Statistics of rogue waves in computer experiments // JETP Letters, 2012, V. 96, Issue 1, pp 66-69.

Measurement of flows around modern commercial ship models

Science.gov (United States)

Kim, W. J.; Van, S. H.; Kim, D. H.

To document the details of flow characteristics around modern commercial ships, global force, wave pattern, and local mean velocity components were measured in the towing tank. Three modern commercial hull models of a container ship (KRISO container ship = KCS) and of two very large crude-oil carriers (VLCCs) with the same forebody and slightly different afterbody (KVLCC and KVLCC2) having bow and stern bulbs were selected for the test. Uncertainty analysis was performed for the measured data using the procedure recommended by the ITTC. Obtained experimental data will provide a good opportunity to explore integrated flow phenomena around practical hull forms of today. Those can be also used as the validation data for the computational fluid dynamics (CFD) code of both inviscid and viscous flow calculations.

Nuclear powered ships. Findings from a feasibility study

International Nuclear Information System (INIS)

Namikawa, Shunichiro; Maerli, Morten Bremer; Hoffmann, Peter Nyegaard; Brodin, Erik

2011-01-01

Nuclear shipping is attractive for several reasons, one of which is its positive effect on emissions (CO 2 , NOx and SOx). The benefits, however, do not come without risks of possible harmful effects on humans and wildlife. Nuclear ships set themselves apart from conventional ships, as well as from on-shore nuclear power-plants, on several counts. 1) The reactor-unit are non-stationary, and the reactor is subject to the ship motions. 2) Ship reactors must be compact due to space constraints. 3) Special design considerations are required to ensure reactor safety and security, as well as to enable refuelling. 4) A naval nuclear fuel cycle infrastructure for fuel fabrication, handling, and disposal is needed. Technological feasibility of nuclear shipping is by itself inconclusive to a expansion into civilian applications and use. Civilian nuclear propulsion needs to be commercially viable and politically acceptable. Appropriate legislation must be in place, and nuclear shipping concepts with proven safety records and highest possible nuclear proliferation-resistance must be established. Possible 'showstoppers' to a viable nuclear civilian shipping industry are outlined in the paper in view of Political, Technical, Regulatory, Commercial, Safety and Security aspects. Further, different types of ships with different propulsion system are compared in lights of life cycle cost and air emission. (author)

Transition of torque pattern in undulatory locomotion due to wave number variation in resistive force dominated media

Science.gov (United States)

Ding, Yang; Ming, Tingyu

2016-11-01

In undulatory locomotion, torque (bending moment) is required along the body to overcome the external forces from environments and bend the body. Previous observations on animals using less than two wavelengths on the body showed such torque has a single traveling wave pattern. Using resistive force theory model and considering the torque generated by external force in a resistive force dominated media, we found that as the wave number (number of wavelengths on the locomotor's body) increases from 0.5 to 1.8, the speed of the traveling wave of torque decreases. When the wave number increases to 2 and greater, the torque pattern transits from a single traveling wave to a two traveling waves and then a complex pattern that consists two wave-like patterns. By analyzing the force distribution and its contribution to the torque, we explain the speed decrease of the torque wave and the pattern transition. This research is partially supported by the Recruitment Program of Global Young Experts (China).

Resistive effects on helicity-wave current drive generated by Alfven waves in tokamak plasmas

Energy Technology Data Exchange (ETDEWEB)

Bruma, C.; Cuperman, S.; Komoshvili, K. [Tel Aviv Univ. (Israel). Faculty of Exact Sciences

1997-05-01

This work is concerned with the investigation of non-ideal (resistive) MHD effects on the excitation of Alfven waves by externally launched fast-mode waves, in simulated tokamak plasmas; both continuum range, CR ({l_brace}{omega}{sub Alf}(r){r_brace}{sub min} < {omega} < {l_brace}{omega}{sub Alf}(r){r_brace}{sub max}) and discrete range, DR, where global Alfven eigenmodes, GAEs ({omega} < {l_brace}{sub Alf}(r){r_brace}{sub min}) exist, are considered. (Here, {omega}{sub Alf}(r) {identical_to} {omega}{sub Alf}[n(r), B{sub 0}(r)] is an eigenfrequency of the shear Alfven wave). For this, a cylindrical current carrying plasma surrounded by a helical sheet-current antenna and situated inside a perfectly conducting shell is used. Toroidicity effects are simulated by adopting for the axial equilibrium magnetic field component a suitable radial profile; shear and finite relative poloidal magnetic field are properly accounted for. A dielectric tensor appropriate to the physical conditions considered in this paper is derived and presented. (author).

Estimation of Ship Motions Using Closed-Form Expressions

DEFF Research Database (Denmark)

Jensen, Jørgen Juncher; Mansour, A.E.; Olsen, Anders Smærup

2004-01-01

A semi-analytical approach is used to derive frequency response functions for the wave-induced motions for monohull ships. The results are given as closed-form expressions and the required input information for the procedure is restricted to the main dimensions: Length, breadth, draught, block...

Green Shipping Practices of Shipping Firms

Directory of Open Access Journals (Sweden)

Young-Tae Chang

2017-05-01

Full Text Available The primary objective of this study is to provide an empirical research using structural equation modeling to identify the factors that motivate shipping firms to adopt green shipping practices (GSP. Furthermore, it also examines if adopting GSP can enhance the shipping firms’ environmental and productivity performance. The findings show that shipping firms are motivated to adopt GSP mostly by industrial norms set by institutionalized associations. They are also motivated by customers’ demand for environmental friendliness and their own strategy to make good image. Unlike our expectation, government regulations and international environmental laws are not significant in influencing shipping firms to adopt GSP. Moreover, adoption of green shipping practices can improve the environmental and productivity performance of the shipping firms.

Measurement of flows around modern commercial ship models

Energy Technology Data Exchange (ETDEWEB)

Kim, W J; Van, S H; Kim, D H [Korea Research Inst. of Ships and Ocean Engineering, KORDI, Taejon (Korea)

2001-11-01

To document the details of flow characteristics around modern commercial ships, global force, wave pattern, and local mean velocity components were measured in the towing tank. Three modern commercial hull models of a container ship (KRISO container ship = KCS) and of two very large crude-oil carriers (VLCCs) with the same forebody and slightly different afterbody (KVLCC and KVLCC2) having bow and stern bulbs were selected for the test. Uncertainty analysis was performed for the measured data using the procedure recommended by the ITTC. Obtained experimental data will provide a good opportunity to explore integrated flow phenomena around practical hull forms of today. Those can be also used as the validation data for the computational fluid dynamics (CFD) code of both inviscid and viscous flow calculations. (orig.)

dc Resistivity of Quantum Critical, Charge Density Wave States from Gauge-Gravity Duality.

Science.gov (United States)

Amoretti, Andrea; Areán, Daniel; Goutéraux, Blaise; Musso, Daniele

2018-04-27

In contrast to metals with weak disorder, the resistivity of weakly pinned charge density waves (CDWs) is not controlled by irrelevant processes relaxing momentum. Instead, the leading contribution is governed by incoherent, diffusive processes which do not drag momentum and can be evaluated in the clean limit. We compute analytically the dc resistivity for a family of holographic charge density wave quantum critical phases and discuss its temperature scaling. Depending on the critical exponents, the ground state can be conducting or insulating. We connect our results to dc electrical transport in underdoped cuprate high T_{c} superconductors. We conclude by speculating on the possible relevance of unstable, semilocally critical CDW states to the strange metallic region.

dc Resistivity of Quantum Critical, Charge Density Wave States from Gauge-Gravity Duality

Science.gov (United States)

Amoretti, Andrea; Areán, Daniel; Goutéraux, Blaise; Musso, Daniele

2018-04-01

In contrast to metals with weak disorder, the resistivity of weakly pinned charge density waves (CDWs) is not controlled by irrelevant processes relaxing momentum. Instead, the leading contribution is governed by incoherent, diffusive processes which do not drag momentum and can be evaluated in the clean limit. We compute analytically the dc resistivity for a family of holographic charge density wave quantum critical phases and discuss its temperature scaling. Depending on the critical exponents, the ground state can be conducting or insulating. We connect our results to dc electrical transport in underdoped cuprate high Tc superconductors. We conclude by speculating on the possible relevance of unstable, semilocally critical CDW states to the strange metallic region.

Nonlinear dynamic positioning of ships with gain-scheduled wave filtering

DEFF Research Database (Denmark)

Torsetnes, Guttorm; Jouffroy, Jerome; Fossen, Thor I.

This paper presents a globally contracting controller for regulation and dynamic positioning of ships, using only position measurements. For this purpose a globally contracting observer which reconstructs the unmeasured states is constructed. The observer produces accurate estimates of position...

Ship detection in optical remote sensing images based on deep convolutional neural networks

Science.gov (United States)

Yao, Yuan; Jiang, Zhiguo; Zhang, Haopeng; Zhao, Danpei; Cai, Bowen

2017-10-01

Automatic ship detection in optical remote sensing images has attracted wide attention for its broad applications. Major challenges for this task include the interference of cloud, wave, wake, and the high computational expenses. We propose a fast and robust ship detection algorithm to solve these issues. The framework for ship detection is designed based on deep convolutional neural networks (CNNs), which provide the accurate locations of ship targets in an efficient way. First, the deep CNN is designed to extract features. Then, a region proposal network (RPN) is applied to discriminate ship targets and regress the detection bounding boxes, in which the anchors are designed by intrinsic shape of ship targets. Experimental results on numerous panchromatic images demonstrate that, in comparison with other state-of-the-art ship detection methods, our method is more efficient and achieves higher detection accuracy and more precise bounding boxes in different complex backgrounds.

Dynamic analysis of CHASNUPP steam generator structure during shipping

International Nuclear Information System (INIS)

Han Liangbi; Xu Jinkang; Zhou Meiwu; He Yinbiao

1998-07-01

The dynamic analysis of CHASNUPP steam generator during shipping is described, including the simplified mathematical model, acceleration power spectrum of ocean wave induced random vibration, the dynamic analysis of steam generator structure under random loading, the applied computer code and calculated results

Loads for use in the design of ships and offshore structures

DEFF Research Database (Denmark)

Hirdaris, S.E.; Bai, W.; Dessi, Daniele

2014-01-01

The evaluation of structural responses is key element in the design of ships and offshore structures. Fundamental to this is the determination of the design loads to support the Rule requirements and for application in direct calculations. To date, the current design philosophy for the prediction...... of motions and wave-induced loads has been driven by empirical or first-principles calculation procedures based on well-proven applications such as ship motion prediction programs. In recent years, the software, engineering and computer technology available to predict the design loads imposed on ships...... and offshore structures has improved dramatically. Notwithstanding, with the stepwise increase in the size and structural complexity of ships and floating offshore installations and the advances in the framework of Rules and Standards it has become necessary to utilise the latest technologies to assess...

Analysis of ship maneuvering data from simulators

Science.gov (United States)

Frette, V.; Kleppe, G.; Christensen, K.

2011-03-01

We analyze complex manuevering histories of ships obtained from training sessions on bridge simulators. Advanced ships are used in fields like offshore oil exploration: dive support vessels, supply vessels, anchor handling vessels, tugs, cable layers, and multi-purpose vessels. Due to high demands from the operations carried out, these ships need to have very high maneuverability. This is achieved through a propulsion system with several thrusters, water jets, and rudders in addition to standard propellers. For some operations, like subsea maintenance, it is crucial that the ship accurately keeps a fixed position. Therefore, bridge systems usually incorporate equipment for Dynamic Positioning (DP). DP is a method to keep ships and semi submersible rigs in a fixed position using the propulsion systems instead of anchors. It may also be used for sailing a vessel from one position to another along a predefined route. Like an autopilot on an airplane, DP may operate without human involvement. The method relies on accurate determination of position from external reference systems like GPS, as well as a continuously adjusted mathematical model of the ship and external forces from wind, waves and currents. In a specific simulator exercise for offshore crews, a ship is to be taken up to an installation consisting of three nearby oil platforms connected by bridges (Frigg field, North Sea), where a subsea inspection is to be carried out. Due to the many degrees of freedom during maneuvering, including partly or full use of DP, the chosen routes vary significantly. In this poster we report preliminary results on representations of the complex maneuvering histories; representations that allow comparison between crew groups, and, possibly, sorting of the different strategic choices behind.

Effects of ship motions on laminar flow in tubes

Energy Technology Data Exchange (ETDEWEB)

Yan, B.H., E-mail: yanbh1986@163.co [Department of Nuclear Science and Engineering, Naval University of Engineering, 717 Jiefang Street, Wuhan 430033 (China); Yu, L. [Department of Nuclear Science and Engineering, Naval University of Engineering, 717 Jiefang Street, Wuhan 430033 (China); Yang, Y.H. [School of Nuclear Science and Engineering, Shanghai Jiao Tong University, 800 Dong Chuan Road, Shanghai 200240 (China)

2010-01-15

The thermal-hydraulics of barge-mounted floating nuclear desalination plants is the incentive for this study. Laminar flow in tubes in heaving motion is modeled. The friction factor and heat transfer coefficient are obtained. All the equations of laminar flow in steady state are applicable for heeling motion. The effect of ship motions on the laminar developing region is also analyzed. The ship motions can weaken the boundary layer in the laminar developing region and strengthen the laminar frictional resistance. The effect of ship motions on the instability of laminar flow is also investigated. The ship motions do not affect the instability point, but they can shorten the distance between the instability point and the transition point, and cause the transition from laminar flow to turbulent flow to occur earlier.

Surface Ship Shock Modeling and Simulation: Two-Dimensional Analysis

Directory of Open Access Journals (Sweden)

Young S. Shin

1998-01-01

Full Text Available The modeling and simulation of the response of a surface ship system to underwater explosion requires an understanding of many different subject areas. These include the process of underwater explosion events, shock wave propagation, explosion gas bubble behavior and bubble-pulse loading, bulk and local cavitation, free surface effect, fluid-structure interaction, and structural dynamics. This paper investigates the effects of fluid-structure interaction and cavitation on the response of a surface ship using USA-NASTRAN-CFA code. First, the one-dimensional Bleich-Sandler model is used to validate the approach, and second, the underwater shock response of a two-dimensional mid-section model of a surface ship is predicted with a surrounding fluid model using a constitutive equation of a bilinear fluid which does not allow transmission of negative pressures.

Numerical simulation and experimental research on wake field of ships under off-design conditions

Science.gov (United States)

Guo, Chun-yu; Wu, Tie-cheng; Zhang, Qi; Gong, Jie

2016-10-01

Different operating conditions (e.g. design and off-design) may lead to a significant difference in the hydrodynamics performance of a ship, especially in the total resistance and wake field of ships. This work investigated the hydrodynamic performance of the well-known KRISO 3600 TEU Container Ship (KCS) under three different operating conditions by means of Particle Image Velocimetry (PIV) and Computational Fluid Dynamics (CFD). The comparison results show that the use of PIV to measure a ship's nominal wake field is an important method which has the advantages of being contactless and highly accurate. Acceptable agreements between the results obtained by the two different methods are achieved. Results indicate that the total resistances of the KCS model under two off-design conditions are 23.88% and 13.92% larger than that under the designed condition, respectively.

Study on Short-term Variability of Ship Responses in Waves

DEFF Research Database (Denmark)

Nielsen, Ulrik Dam; Iseki, Toshio

2015-01-01

Short-term variability of ship responses is investigated by cross-spectrum analysis. In a steady state condition, it is well known that a certain length of sampled data is required for stable results of the spectral analysis. However, the phase lag between responses, in terms of the phase angle o...

Study on Short-term Variability of Ship Responses in Waves

DEFF Research Database (Denmark)

Iseki, Toshio; Nielsen, Ulrik Dam

2014-01-01

Short-term variability of ship responses is investigated from the view point of cross-spectrum analysis. In a steady state condition, it is well known that a certain length of sampled data are required for stable spectral analysis. However, the phase angle of the cross-spectra has not been discus...

Conditional Stochastic Processes Applied to Wave Load Predictions

DEFF Research Database (Denmark)

Jensen, Jørgen Juncher

2015-01-01

The concept of conditional stochastic processes provides a powerful tool for evaluation and estimation of wave loads on ships and offshore structures. This article first considers conditional waves with a focus on critical wave episodes. Then the inherent uncertainty in the results is illustrated...

Physical, meteorological, wave spectra, and other data from CTD casts and current meters aboard NOAA Ship McARTHUR in the Columbia River (Wash./Oregon) from 1981-05-06 to 1981-11-25 (NODC Accession 8300033)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Physical, meteorological, wave spectra, and other data were collected from CTD casts and current meters from NOAA Ship McARTHUR and other platforms in the Columbia...

Analysis of a ship-to-ship collision

International Nuclear Information System (INIS)

Porter, V.L.; Ammerman, D.J.

1996-01-01

Sandia National Laboratories is involved in a safety assessment for the shipment of radioactive material by sea. One part of this study is investigation of the consequences of ship-to-ship collisions. This paper describes two sets of finite element analyses performed to assess the structural response of a small freighter and the loading imparted to radioactive material (RAM) packages during several postulated collision scenarios with another ship. The first series of analyses was performed to evaluate the amount of penetration of the freighter hull by a striking ship of various masses and initial velocities. Although these analyses included a representation of a single RAM package, the package was not impacted during the collision so forces on the package could not be computed. Therefore, a second series of analyses incorporating a representation of a row of seven packages was performed to ensure direct package impact by the striking ship. Average forces on a package were evaluated for several initial velocities and masses of the striking ship. In addition to. providing insight to ship and package response during a few postulated ship collisions scenarios, these analyses will be used to benchmark simpler ship collision models used in probabilistic risk assessment analyses

Design study of ship based nuclear power reactor

International Nuclear Information System (INIS)

Su'ud, Zaki; Fitriyani, Dian

2002-01-01

Preliminary design study of ship based nuclear power reactors has been performed. In this study the results of thermohydraulics analysis is presented especially related to behaviour of ship motion in the sea. The reactors are basically lead-bismuth cooled fast power reactors using nitride fuels to enhance neutronics and safety performance. Some design modification are performed for feasibility of operation under sea wave movement. The system use loop type with relatively large coolant pipe above reactor core. The reactors does not use IHX, so that the heat from primary coolant system directly transferred to water-steam loop through steam generator. The reactors are capable to be operated in difference power level during night and noon. The reactors however can also be used totally or partially to produce clean water through desalination of sea water. Due to the influence of sea wave movement the analysis have to be performed in three dimensional analysis. The computation time for this analysis is speeded up using Parallel Virtual Machine (PVM) Based multi processor system

The Effect of Hull Biofouling on Parameters Characterising Ship Propulsion System Efficiency

Directory of Open Access Journals (Sweden)

Tarełko Wiesła

2015-01-01

Full Text Available One of most important issues concerning technical objects is the increase of their operating performance. For a ship this performance mainly depends on the efficiency of its main pro-pulsion system and the resistance generated during its motion on water. The overall ship re-sistance, in turn, mainly depends on the hull friction resistance, closely related with the pres-ence of different types of roughness on the hull surface, including underwater part biofouling. The article analyses the effect of hull biofouling on selected parameters characterising the efficiency of the ship propulsion system with adjustable propeller. For this purpose a two-year research experiment was performed on a sailing vessel during its motor navigation phases. Based on the obtained results, three groups of characteristics were worked out for different combinations of engine rotational speed and adjustable propeller pitch settings. The obtained results have revealed that the phenomenon of underwater hull biofouling affects remarkably the parameters characterising propulsion system efficiency. In particular, the development of the biofouling layer leads to significant reduction of the speed of navigation.

Damage scenarios and an onboard support system for damaged ships

Directory of Open Access Journals (Sweden)

Choi Jin

2014-06-01

Full Text Available Although a safety assessment of damaged ships, which considers environmental conditions such as waves and wind, is important in both the design and operation phases of ships, in Korea, rules or guidelines to conduct such assessments are not yet developed. However, NATO and European maritime societies have developed guidelines for a safety assessment. Therefore, it is required to develop rules or guidelines for safety assessments such as the Naval Ship Code (NSC of NATO. Before the safety assessment of a damaged ship can be performed, the available damage scenarios must be developed and the safety assessment criteria must be established. In this paper, the parameters related to damage by accidents are identified and categorized when developing damage scenarios. The need for damage safety assessment criteria is discussed, and an example is presented. In addition, a concept and specifications for the DB-based supporting system, which is used in the operation phases, are proposed.

Cyclic Fatigue Resistance of Reciproc Blue, Reciproc, and WaveOne Gold Reciprocating Instruments.

Science.gov (United States)

Keskin, Cangül; Inan, Uğur; Demiral, Murat; Keleş, Ali

2017-08-01

The aim of the present study was to compare the cyclic fatigue resistance of Reciproc Blue R25 (VDW, Munich, Germany) with Reciproc R25 (VDW) and WaveOne Gold Primary (Denstply Maillefer, Ballaigues, Switzerland). Fifteen Reciproc Blue R25, 15 Reciproc R25, and 15 WaveOne Gold Primary instruments were collected and tested in a dynamic cyclic fatigue test device, which has an artificial canal with a 60° angle of curvature and a 5-mm radius of curvature. All instruments were operated until fracture occurred, and time to fracture (TF) and the lengths of the fractured fragments were recorded. The mean and standard deviations of TF and fragment length were calculated for each reciprocating system. TF data were subjected to Kruskal-Wallis 1-way analysis of variance and the Dunn test, whereas fractured fragment length data were subjected to 1-way analysis of variance (P  .05). Reciproc Blue R25 instruments had significantly higher cyclic fatigue resistance than WaveOne Gold and Reciproc R25 instruments. Copyright © 2017 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Phase spectral composition of wind generated ocean surface waves

Digital Repository Service at National Institute of Oceanography (India)

Varkey, M.J.

A study of the composition of the phase spectra of wind generated ocean surface waves is carried out using wave records collected employing a ship borne wave recorder. It is found that the raw phase spectral estimates could be fitted by the Uniform...

Enhanced situational technologies applied to ship channels

Science.gov (United States)

Helgeson, Michael A.; Wacker, Roger A.

1997-06-01

The Houston Ship Channel ranks as America's number one port in foreign tonnage by welcoming more than 50,000 cargo ships and barges annually. Locally 196,000 jobs, 5.5 billion dollars in business revenue and 213 million dollars in taxes are generated. Unfortunately, 32 days of each year vessel traffic stops for hours due to fog causing an estimated 40- 100 million dollars loss as ships idly wait in the channel for weather to clear. In addition, poor visibility has contributed to past vessel collisions which have resulted in channel closure, and associated damage to property and the environment. Today's imaging technology for synthetic vision systems and enhanced situational awareness systems offers a new solution to this problem. Whereas, typically these systems have been targeted at aircraft landing systems the channel navigation application provides a peripheral ground based market. This paper describes two imaging solutions to the problem. One using an active 35 GHz scanning radar and the other using a 94 GHz passive millimeter wave camera.

Development of superconducting ship propulsion system

International Nuclear Information System (INIS)

Sakuraba, Junji; Mori, Hiroyuki; Hata, Fumiaki; Sotooka, Koukichi

1991-01-01

When we plan displacement-type monohull high speed vessels, it is difficult to get the hull form with the wave-making resistance minimum, because the stern shape is restricted by arrangement of propulsive machines and shafts. A small-sized and light-weight propulsive machines will reduce the limit to full form design. Superconducting technology will have capability of realizing the small-sized and light-weight propulsion motor. The superconducting electric propulsion system which is composed of superconducting propulsion motors and generators, seems to be an ideal propulsion system for future vehicles. We have constructed a 480 kW superconducting DC homopolar laboratory test motor for developing this propulsion system. The characteristic of this motor is that it has a superconducting field winding and a segmented armature drum. The superconducting field winding which operates in the persistent current mode, is cooled by a condensation heat exchanger and helium refigerating system built into the cryostat of the superconducting field winding. The operating parameters of this motor agreed well with the design parameters. Using the design concepts of this motor, we have conceptually designed a 150,000-200,000 PS superconducting electric propulsive system for a displacement-type monohull high speed ship. (author)

Producing acoustic 'Frozen Waves': Simulated experiments with diffraction/attenuation resistant beams, in lossy media

OpenAIRE

Prego-Borges, Jose' L.; Zamboni-Rached, Michel; Recami, Erasmo; Tavares-Costa, Eduardo

2013-01-01

The so-called Localized Waves (LW), and the "Frozen Waves" (FW), have arisen significant attention in the areas of Optics and Ultrasound, because of their surprising energy localization properties. The LWs resist the effects of diffraction for large distances, and possess an interesting self-reconstruction (self-healing) property, after obstacles with size smaller than the antenna's; while the FWs, a sub-class of theirs, offer the possibility of arbitrarily modeling the field longitudinal int...

Cyclic fatigue resistance of R-Pilot, WaveOne Gold Glider, and ProGlider glide path instruments.

Science.gov (United States)

Keskin, Cangül; İnan, Uğur; Demiral, Murat; Keleş, Ali

2018-02-17

The aim of the present study was to compare the cyclic fatigue resistance of R-Pilot (VDW; Munich, Germany) with ProGlider (Denstply Sirona; Ballaigues, Switzerland) and WaveOne Gold Glider (Denstply Sirona; Ballaigues, Switzerland) glide path instruments. R-Pilot, ProGlider, and WaveOne Gold Glider instruments were collected (n = 15) and tested in a dynamic cyclic fatigue test device, which has an artificial canal with 60° angle of curvature and a 5-mm radius of curvature. All instruments were operated until fracture occurred, and both time to fracture (TF) and the lengths of the fractured fragments were recorded. Mean and standard deviations of TF and fragment length were calculated for each reciprocating system. TF data and fractured fragment length data were subjected to one-way ANOVA and post-hoc Tukey tests (P  0.05). Weibull analysis revealed that WaveOne Gold Glider showed the highest predicted TF value for 99% survival rate, which was followed by R-Pilot and ProGlider. Regarding the length of the fractured tips, there were no significant differences among the instruments (P > 0.05). The reciprocating WaveOne Gold Glider and R-Pilot instruments had significantly higher cyclic fatigue resistance than rotary ProGlider instruments. This study reported that novel reciprocating glide path instruments exhibited higher cyclic fatigue resistance than rotating glide path instrument.

The shipping man adventures in ship finance

CERN Document Server

McCleery, Matthew

2013-01-01

When restless New York City hedge fund manager Robert Fairchild watches the Baltic Dry Cargo Index plunge 97%, registering an all-time high and a 25-year low within the span of just six months, he decides to buy a ship. Immediately fantasizing about naming a vessel after his wife, carrying a string of worry beads and being able to introduce himself as a "shipowner" at his upcoming college reunion, Fairchild immediately embarks on an odyssey into the most exclusive, glamorous and high stakes business in the world. From pirates off the coast of Somalia and on Wall Street to Greek and Norwegian shipping magnates, the education of Robert Fairchild is an expensive one. In the end, he loses his hedge fund, but he gains a life - as a Shipping Man. Part fast paced financial thriller, part ship finance text book, The Shipping Man is 310 pages of required reading for anyone with an interest in capital formation for shipping.

Numerical simulation of ship motion in offshore and harbour areas

DEFF Research Database (Denmark)

Christensen, Erik Damgaard; Jensen, Bjarne; Mortensen, Simon Brandi

2008-01-01

A method for simulating the motions and mooring forces of a moored ship subject to wave forcing has been further developed and validated for both the open water case and inside harbour areas. The method was originally developed and reported in Bingham (2000). The simulation tool is named WAMSIM...

Are nuclear ships environmentally safer than conventionally powered ships

International Nuclear Information System (INIS)

Bone, C.A.; Molgaard, C.A.; Helmkamp, J.C.; Golbeck, A.L.

1988-01-01

An epidemiologic analysis was conducted to determine if risk of hospitalization varied by age, ship type, or occupation between nuclear and conventional powered ship crews in the U.S. Navy. Study cohorts consisted of all male enlisted personnel who served exclusively aboard conventional or nuclear powered aircraft carriers and cruisers during the years 1975-1979; cases were those men hospitalized during this period (N = 48,242). Conventional ship personnel showed significantly elevated rates of injury and disease when compared to nuclear ship personnel. The largest relative risks by age occurred for conventional ship crewmen less than 30 years old. Seaman, logistics (supply), and healthcare personnel serving aboard conventional ships comprised the occupational groups exhibiting the highest hospitalization rate differentials. The results strongly suggest that nuclear ships provide a healthier, safer working and living environment than conventional ships

Shipping

NARCIS (Netherlands)

Wijnolst, N.; Wergeland, T.

1996-01-01

Shipping is a multi-faceted industry which is rather complex to define from an academic point of view. This book attempts to grasp these complexities and provide the reader with an overview of the main topics and terminology in shipping. The book is based on material from our courses in shipping at

Embedded Artificial Neuval Network-Based Real-Time Half-Wave Dynamic Resistance Estimation during the A.C. Resistance Spot Welding Process

Directory of Open Access Journals (Sweden)

Liang Gong

2013-01-01

Full Text Available Online monitoring of the instantaneous resistance variation during the A.C. resistance spot welding is of paramount importance for the weld quality control. On the basis of the welding transformer circuit model, a new method is proposed to measure the transformer primary-side signal for estimating the secondary-side resistance in each 1/4 cycle. The tailored computing system ensures that the measuring method possesses a real-time computational capacity with satisfying accuracy. Since the dynamic resistance cannot be represented via an explicit function with respect to measurable parameters from the primary side of the welding transformer, an offline trained embedded artificial neural network (ANN successfully realizes the real-time implicit function calculation or estimation. A DSP-based resistance spot welding monitoring system is developed to perform ANN computation. Experimental results indicate that the proposed method is applicable for measuring the dynamic resistance in single-phase, half-wave controlled rectifier circuits.

46 CFR 111.01-11 - Corrosion-resistant parts.

Science.gov (United States)

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Corrosion-resistant parts. 111.01-11 Section 111.01-11 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS General § 111.01-11 Corrosion-resistant parts. Each enclosure and part of electric...

PPM-based System for Guided Waves Communication Through Corrosion Resistant Multi-wire Cables

Science.gov (United States)

Trane, G.; Mijarez, R.; Guevara, R.; Pascacio, D.

Novel wireless communication channels are a necessity in applications surrounded by harsh environments, for instance down-hole oil reservoirs. Traditional radio frequency (RF) communication schemes are not capable of transmitting signals through metal enclosures surrounded by corrosive gases and liquids. As an alternative to RF, a pulse position modulation (PPM) guided waves communication system has been developed and evaluated using a corrosion resistant 4H18 multi-wire cable, commonly used to descend electronic gauges in down-hole oil applications, as the communication medium. The system consists of a transmitter and a receiver that utilizes a PZT crystal, for electrical/mechanical coupling, attached to each extreme of the multi-wire cable. The modulator is based on a microcontroller, which transmits60 kHz guided wave pulses, and the demodulator is based on a commercial digital signal processor (DSP) module that performs real time DSP algorithms. Experimental results are presented, which were obtained using a 1m corrosion resistant 4H18multi-wire cable, commonly used with downhole electronic gauges in the oil sector. Although there was significant dispersion and multiple mode excitations of the transmitted guided wave energy pulses, the results show that data rates on the order of 500 bits per second are readily available employing PPM and simple communications techniques.

On the Global Ship Hull Bending Energy in Ship Collisions

DEFF Research Database (Denmark)

Pedersen, Preben Terndrup; Li, Y.

2004-01-01

During ship collisions part of the kinetic energy of the involved vessels prior to contact is absorbed as energy dissipated by crushing of the hull structures, by friction and by elastic energy. The purpose of this report is to present an estimate of the elastic energy that can be stored in elastic...... hull vibrations during a ship collision. When a ship side is strengthened in order to improve the crashworthiness it has been argued in the scientific literature that a non trivial part of the energy released for structural deformation during the collision can be absorbed as elastic energy in global...... ship hull vibrations, such that with strong ship sides less energy has to be spent in crushing of the striking ship bow and/or the struck ship side. In normal ship-ship collision analyses both the striking and struck ship are usually considered as rigid bodies where structural crushing is confined...

A Novel Approach to Turbulence Stimulation for Ship-Model Testing

Science.gov (United States)

2010-05-11

a given hull form. As van Manen and van Oossanen note, ship resistance is related to “the proportions and shape… of the hull, the size and type of...propulsion plant to provide motive power, and the device or system to transform the power into effective thrust” ( van Manen and van Oossanen, 1988...what is known as the Ship-Model Tester’s Dilemma, which van Manen and van Oossanen define as “the conditions of mechanical similitude for both friction

Preprint of the Fall 1996 Meeting of the Society of Naval Architects of Japan; Nippon zosen gakkai (1996 nen) shuki koen ronbun maezuri

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-12-31

Among the papers made public in the Fall 1996 Meeting of the Society of Naval Architects of Japan, 40 papers pertaining to resistance, propulsion, motion, and ocean were summed up as the first book. Concerning the resistance relation, the book included papers titled Analysis of wave-making characteristics of ship form by Mathieu function expansions of wave-amplitude functions derived from wave analysis; Studies on surface tension effect on free surface flow around floating models; Numerical computation of viscous flows with free surface around a series 60 model; etc. As to the propulsion and motion, Design system for optimum contra-rotating propellers; Performance of the patrol icebreaker `TESHIO` in ice-covered waters; A study on effect of bow shape on icebreaking resistance; Time domain analysis of ship response in directional irregular wave; Study on prediction method for hydrodynamic force acting on a ship hull in swaying motion; etc. With relation to the ocean relation, On statistical properties of wave amplitudes in stormy sea; Statistical properties of encounter wave grouping phenomena in following and quartering seas; Development of hybrid type on board measuring system for directional wave spectrum; etc.

Preprint of the Fall 1996 Meeting of the Society of Naval Architects of Japan; Nippon zosen gakkai (1996 nen) shuki koen ronbun maezuri

Energy Technology Data Exchange (ETDEWEB)

NONE

1996-12-31

Among the papers made public in the Fall 1996 Meeting of the Society of Naval Architects of Japan, 40 papers pertaining to resistance, propulsion, motion, and ocean were summed up as the first book. Concerning the resistance relation, the book included papers titled Analysis of wave-making characteristics of ship form by Mathieu function expansions of wave-amplitude functions derived from wave analysis; Studies on surface tension effect on free surface flow around floating models; Numerical computation of viscous flows with free surface around a series 60 model; etc. As to the propulsion and motion, Design system for optimum contra-rotating propellers; Performance of the patrol icebreaker `TESHIO` in ice-covered waters; A study on effect of bow shape on icebreaking resistance; Time domain analysis of ship response in directional irregular wave; Study on prediction method for hydrodynamic force acting on a ship hull in swaying motion; etc. With relation to the ocean relation, On statistical properties of wave amplitudes in stormy sea; Statistical properties of encounter wave grouping phenomena in following and quartering seas; Development of hybrid type on board measuring system for directional wave spectrum; etc.

“The History of all Hitherto Existing Society:” Class Struggle and the Current Wave of Resistance

Directory of Open Access Journals (Sweden)

Todd Wolfson

2018-05-01

Full Text Available Across the last decade we have witnessed a growing wave of resistance across the globe. In this article we argue that it is critical to utilise class analysis to understand contemporary social movements. We maintain that class analysis begins with understanding class as a series of relations and/or processes that condition both the objective and subjective dimensions of class. Following this, we illustrate how sectors of the contemporary working class are in struggle, yet struggle differently, based on their structural location as well as differing nature of their resistance. In taking this approach to class and social movements, we argue that scholars can begin to unmask the central role of capitalism and the attending regimes of accumulation in the current wave of resistance even when they appear disconnected.

On the global ship hull bending energy in ship collisions

DEFF Research Database (Denmark)

Pedersen, Preben Terndrup; Li, Yujie

2009-01-01

During ship collisions part of the kinetic energy of the involved vessels immediately prior to contact is absorbed as energy dissipated by crushing of the hull structures, by friction and by elastic energy. The purpose of this report is to present an estimate of the elastic energy that can...... be stored in elastic hull vibrations during a ship collision. When a ship side is strengthened in order to improve the crashworthiness it has been argued in the scientific literature that a non-trivial part of the energy released for structural deformation during the collision can be absorbed as elastic...... energy in global ship hull vibrations, such that with strong ship sides less energy has to be spent in crushing of the striking ship bow and/or the struck ship side. In normal ship–ship collision analyses both the striking and struck ship are usually considered as rigid bodies where structural crushing...

Adaptability of solar energy conversion systems on ships

Science.gov (United States)

Visa, I.; Cotorcea, A.; Neagoe, M.; Moldovan, M.

2016-08-01

International trade of goods largely uses maritime/transoceanic ships driven by engines using fossil fuels. This two centuries tradition is technologically mature but significantly adds to the CO2 emissions; therefore, recent trends focus on on-board implementation of systems converting the solar energy into power (photovoltaic systems) or heat (solar-thermal systems). These systems are carbon-emissions free but are still under research and plenty of effort is devoted to fast reach maturity and feasibility. Unlike the systems implemented in a specific continental location, the design of solar energy conversion systems installed on shipboard has to face the problem generated by the system base motion along with the ship travelling on routes at different latitudes: the navigation direction and sense and roll-pitch combined motion with reduced amplitude, but with relatively high frequency. These raise highly interesting challenges in the design and development of mechanical systems that support the maximal output in terms of electricity or heat. The paper addresses the modelling of the relative position of a solar energy conversion surface installed on a ship according to the current position of the sun; the model is based on the navigation trajectory/route, ship motion generated by waves and the relative sun-earth motion. The model describes the incidence angle of the sunray on the conversion surface through five characteristic angles: three used to define the ship orientation and two for the solar angles; based on, their influence on the efficiency in solar energy collection is analyzed by numerical simulations and appropriate recommendations are formulated for increasing the solar energy conversion systems adaptability on ships.

Mathematical model of snake-type multi-directional wave generation

Science.gov (United States)

Muarif; Halfiani, Vera; Rusdiana, Siti; Munzir, Said; Ramli, Marwan

2018-01-01

Research on extreme wave generation is one intensive research on water wave study because the fact that the occurrence of this wave in the ocean can cause serious damage to the ships and offshore structures. One method to be used to generate the wave is self-correcting. This method controls the signal on the wavemakers in a wave tank. Some studies also consider the nonlinear wave generation in a wave tank by using numerical approach. Study on wave generation is essential in the effectiveness and efficiency of offshore structure model testing before it can be operated in the ocean. Generally, there are two types of wavemakers implemented in the hydrodynamic laboratory, piston-type and flap-type. The flap-type is preferred to conduct a testing to a ship in deep water. Single flap wavemaker has been explained in many studies yet snake-type wavemaker (has more than one flap) is still a case needed to be examined. Hence, the formulation in controlling the wavemaker need to be precisely analyzed such that the given input can generate the desired wave in the space-limited wave tank. By applying the same analogy and methodhology as the previous study, this article represents multi-directional wave generation by implementing snake-type wavemakers.

Wave Climate and Wave Mixing in the Marginal Ice Zones of Arctic Seas, Observations and Modelling

Science.gov (United States)

2015-09-30

measured by R/V Lance ( black solid line) and predicted by SWAN ( black dashed line) and the ship velocity (grey solid line). (c) BFI ( black solid line) and...and potential future trends; and WAVEWATCH-III® and SWAN wave models with new physics, adapted and validated for the Beaufort and Chukchi Seas...nondimensional spectral width ν ( black dashed line). (d–i) Selected photographs from the ship show local sea ice state. Fig. 6 illustrates a

Water Waves The Mathematical Theory with Applications

CERN Document Server

Stoker, J J

2011-01-01

Offers an integrated account of the mathematical hypothesis of wave motion in liquids with a free surface, subjected to gravitational and other forces. Uses both potential and linear wave equation theories, together with applications such as the Laplace and Fourier transform methods, conformal mapping and complex variable techniques in general or integral equations, methods employing a Green's function. Coverage includes fundamental hydrodynamics, waves on sloping beaches, problems involving waves in shallow water, the motion of ships and much more.

Wave statistics around the Indian coast based on ship observed data

Digital Repository Service at National Institute of Oceanography (India)

Chandramohan, P.; SanilKumar, V.; Nayak, B.U.

the rest of the year. Waves are higher during the southwest monsoon (June-September) all around the Indian Coasts, with highest intensity of wave activity occurring off northern part of the West Coast and off southern most part of the peninsular India. Wave...

Noise source analysis of nuclear ship Mutsu plant using multivariate autoregressive model

International Nuclear Information System (INIS)

Hayashi, K.; Shimazaki, J.; Shinohara, Y.

1996-01-01

The present study is concerned with the noise sources in N.S. Mutsu reactor plant. The noise experiments on the Mutsu plant were performed in order to investigate the plant dynamics and the effect of sea condition and and ship motion on the plant. The reactor noise signals as well as the ship motion signals were analyzed by a multivariable autoregressive (MAR) modeling method to clarify the noise sources in the reactor plant. It was confirmed from the analysis results that most of the plant variables were affected mainly by a horizontal component of the ship motion, that is the sway, through vibrations of the plant structures. Furthermore, the effect of ship motion on the reactor power was evaluated through the analysis of wave components extracted by a geometrical transform method. It was concluded that the amplitude of the reactor power oscillation was about 0.15% in normal sea condition, which was small enough for safe operation of the reactor plant. (authors)

a Novel Ship Detection Method for Large-Scale Optical Satellite Images Based on Visual Lbp Feature and Visual Attention Model

Science.gov (United States)

Haigang, Sui; Zhina, Song

2016-06-01

Reliably ship detection in optical satellite images has a wide application in both military and civil fields. However, this problem is very difficult in complex backgrounds, such as waves, clouds, and small islands. Aiming at these issues, this paper explores an automatic and robust model for ship detection in large-scale optical satellite images, which relies on detecting statistical signatures of ship targets, in terms of biologically-inspired visual features. This model first selects salient candidate regions across large-scale images by using a mechanism based on biologically-inspired visual features, combined with visual attention model with local binary pattern (CVLBP). Different from traditional studies, the proposed algorithm is high-speed and helpful to focus on the suspected ship areas avoiding the separation step of land and sea. Largearea images are cut into small image chips and analyzed in two complementary ways: Sparse saliency using visual attention model and detail signatures using LBP features, thus accordant with sparseness of ship distribution on images. Then these features are employed to classify each chip as containing ship targets or not, using a support vector machine (SVM). After getting the suspicious areas, there are still some false alarms such as microwaves and small ribbon clouds, thus simple shape and texture analysis are adopted to distinguish between ships and nonships in suspicious areas. Experimental results show the proposed method is insensitive to waves, clouds, illumination and ship size.

A New Slender-Ship Theory of Wave Resistance.

Science.gov (United States)

1981-01-01

then have / .i= (n /n+ tD / +nxt t/ td ).i = n X /an+t x /31-n t a4/ad,x x zy where 5 /Zn is the derivative of in the outward normal direction n to h, as was...function k(t) 1(1+t2 ) /2K(t)/ 4bd is given below. For shortness, the notat ion 2 1/2 2 2 1/2 2 2 2, =(l+t ) 12F 2 b=L(l+t2 //2F2 dl~ / will be used

The activity-based methodology to assess ship emissions - A review.

Science.gov (United States)

Nunes, R A O; Alvim-Ferraz, M C M; Martins, F G; Sousa, S I V

2017-12-01

Several studies tried to estimate atmospheric emissions with origin in the maritime sector, concluding that it contributed to the global anthropogenic emissions through the emission of pollutants that have a strong impact on hu' health and also on climate change. Thus, this paper aimed to review published studies since 2010 that used activity-based methodology to estimate ship emissions, to provide a summary of the available input data. After exclusions, 26 articles were analysed and the main information were scanned and registered, namely technical information about ships, ships activity and movement information, engines, fuels, load and emission factors. The larger part of studies calculating in-port ship emissions concluded that the majority was emitted during hotelling and most of the authors allocating emissions by ship type concluded that containerships were the main pollutant emitters. To obtain technical information about ships the combined use of data from Lloyd's Register of Shipping database with other sources such as port authority's databases, engine manufactures and ship-owners seemed the best approach. The use of AIS data has been growing in recent years and seems to be the best method to report activities and movements of ships. To predict ship powers the Hollenbach (1998) method which estimates propelling power as a function of instantaneous speed based on total resistance and use of load balancing schemes for multi-engine installations seemed to be the best practices for more accurate ship emission estimations. For emission factors improvement, new on-board measurement campaigns or studies should be undertaken. Regardless of the effort that has been performed in the last years to obtain more accurate shipping emission inventories, more precise input data (technical information about ships, engines, load and emission factors) should be obtained to improve the methodology to develop global and universally accepted emission inventories for an

An Efficiency Optimizing Shaft Speed Control for Ships in Moderate Seas

DEFF Research Database (Denmark)

Blanke, Mogens; Pivano, Luca; Johansen, Tor Arne

2007-01-01

Ships in moderate sea experience time-varying thrust and torque load on the shaft of their prime mover. The reason is the varying inflow velocity to the propeller during the passage of a wave. This variation has been considered a nuisance to the main engine control where the induced fluctuations...

Green shipping management

CERN Document Server

Lun, Y H Venus; Wong, Christina W Y; Cheng, T C E

2016-01-01

This book presents theory-driven discussion on the link between implementing green shipping practices (GSP) and shipping firm performance. It examines the shipping industry’s challenge of supporting economic growth while enhancing environmental performance. Consisting of nine chapters, the book covers topics such as the conceptualization of green shipping practices (GSPs), measurement scales for evaluating GSP implementation, greening capability, greening and performance relativity (GPR), green management practice, green shipping network, greening capacity, and greening propensity. In view of the increasing quest for environment protection in the shipping sector, this book provides a good reference for firms to understand and evaluate their capability in carrying out green operations on their shipping activities.

The activity-based methodology to assess ship emissions - A review

International Nuclear Information System (INIS)

Nunes, R.A.O.; Alvim-Ferraz, M.C.M.; Martins, F.G.; Sousa, S.I.V.

2017-01-01

Several studies tried to estimate atmospheric emissions with origin in the maritime sector, concluding that it contributed to the global anthropogenic emissions through the emission of pollutants that have a strong impact on hu' health and also on climate change. Thus, this paper aimed to review published studies since 2010 that used activity-based methodology to estimate ship emissions, to provide a summary of the available input data. After exclusions, 26 articles were analysed and the main information were scanned and registered, namely technical information about ships, ships activity and movement information, engines, fuels, load and emission factors. The larger part of studies calculating in-port ship emissions concluded that the majority was emitted during hotelling and most of the authors allocating emissions by ship type concluded that containerships were the main pollutant emitters. To obtain technical information about ships the combined use of data from Lloyd's Register of Shipping database with other sources such as port authority's databases, engine manufactures and ship-owners seemed the best approach. The use of AIS data has been growing in recent years and seems to be the best method to report activities and movements of ships. To predict ship powers the Hollenbach (1998) method which estimates propelling power as a function of instantaneous speed based on total resistance and use of load balancing schemes for multi-engine installations seemed to be the best practices for more accurate ship emission estimations. For emission factors improvement, new on-board measurement campaigns or studies should be undertaken. Regardless of the effort that has been performed in the last years to obtain more accurate shipping emission inventories, more precise input data (technical information about ships, engines, load and emission factors) should be obtained to improve the methodology to develop global and universally accepted emission inventories

Reliability Analysis of Dynamic Stability in Waves

DEFF Research Database (Denmark)

Søborg, Anders Veldt

2004-01-01

exhibit sufficient characteristics with respect to slope at zero heel (GM value), maximum leverarm, positive range of stability and area below the leverarm curve. The rule-based requirements to calm water leverarm curves are entirely based on experience obtained from vessels in operation and recorded......The assessment of a ship's intact stability is traditionally based on a semi-empirical deterministic concept that evaluates the characteristics of ship's calm water restoring leverarm curves. Today the ship is considered safe with respect to dynamic stability if its calm water leverarm curves...... accidents in the past. The rules therefore only leaves little room for evaluation and improvement of safety of a ship's dynamic stability. A few studies have evaluated the probability of ship stability loss in waves using Monte Carlo simulations. However, since this probability may be in the order of 10...

Selection of the optimum combination of responses for Wave Buoy Analogy - An approach based on local sensitivity analysis

DEFF Research Database (Denmark)

Montazeri, Najmeh; Nielsen, Ulrik Dam; Jensen, Jørgen Juncher

2016-01-01

One method to estimate the wave spectrum onboard ships is to use measured ship responses. In this method, known also as Wave Buoy Analogy, amongst various responses that are available from sensor measurements, a couple of responses (at least three) are usually utilized. Selec-tion of the best com...

Shipping

OpenAIRE

Wijnolst, N.; Wergeland, T.

1996-01-01

Shipping is a multi-faceted industry which is rather complex to define from an academic point of view. This book attempts to grasp these complexities and provide the reader with an overview of the main topics and terminology in shipping. The book is based on material from our courses in shipping at the universities in Delft and Bergen. As with our lectures, we draw upon quite a va ried material, from research studies at a high academic level to lower level student work and purely descriptive ...

Wind and Current Forces Acting on Canadian Forces Ships During Tug Operations

Science.gov (United States)

2002-11-01

McTaggart and Sav- age [1] describe model tests conducted on a generic frigate model to determine wind forces influencing ship capsize. Van Manen and van ...Fn will be 0.06. Based on data presented by van Manen and van Oossanen [2], the fric- tional resistance coefficient will be approximately 0.002 and...Conference on Stability of Ships and Ocean Vehicles (Melbourne, Florida, 1994). 2. J.D. van Manen and P. van Oossanen, Principles of Naval Architecture, Volume

Safety analysis report for packaging: neutron shipping cask, model 0.5T

International Nuclear Information System (INIS)

Peterson, R.T.

1976-01-01

The Safety Analysis Report for Packaging demonstrates that the neutron shipping cask can safely transport, in solid or powder form, all isotopes of uranium, plutonium, americium, curium, berkelium, californium, einsteinium, and fermium. The shipping cask and its contents are described. It also evaluates transport conditions, structural parameters (e.g., load resistance, pressure and impact effects, lifting and tiedown devices), and shielding. Finally, it discusses compliance with Chapter 0529 of the Energy Research and Development Administration Manual

Safety analysis report for packaging (SARP) of the Oak Ridge National Laboratory Foamglas Shipping Container

International Nuclear Information System (INIS)

Klima, B.B.; Shappert, L.B.; Seagren, R.D.; Box, W.D.

1979-01-01

An analytical evaluation of the ORNL Foamglas Shipping Container was made to demonstrate its compliance with the regulations governing offsite radioactive material shipping packages. The evaluation encompassed five primary categories: structural integrity, thermal resistance, radiation shielding, nuclear criticality safety, and quality assurance. The results of the evaluation show that the container complies with the applicable regulations

Designing Adaptable Ships: Modularity and Flexibility in Future Ship Designs

Science.gov (United States)

2016-01-01

with motors, belts, shafts , seals, valves, hose spindles , and switches. If ship installation is not installed, the system will be status quo. Ship...Impact: the current centrifugal purifiers (Alfa-Laval) have experienced frequent failures with motor, belts, shafts , seals, valves, hose spindles ... Designing Adaptable Ships Modularity and Flexibility in Future Ship Designs John F. Schank, Scott Savitz, Ken Munson, Brian Perkinson, James

Research progress of anti-icing/deicing technologies for polar ships and offshore platforms

Directory of Open Access Journals (Sweden)

XIE Qiang

2017-01-01

Full Text Available The polar regions present adverse circumstances of high humidity and strong air-sea exchange. As such, the surfaces of ships and platforms (oil exploiting and drilling platforms serving in polar regions can easily be frozen by ice accretion, which not only affects the operation of the equipment but also threatens safety. This paper summarizes the status of the anti-icing/deicing technologies of both China and abroad for polar ships and offshore platforms, and introduces the various effects of ice accretion on polar ships and offshore platforms, and the resulting safety impacts. It then reviews existing anti-icing/deicing technologies and methods of both China and abroad, including such active deicing methods as electric heating, infrared heating and ultrasonic guided wave deicing, as well as such passive deicing methods as super hydrophobic coating, sacrificial coating, aqueous lubricating layer coating and low cross-link density (with interfacial slippage coating, summarizes their applicability to polar ships and offshore platforms, and finally discusses their advantages/disadvantages.

Modelling Analysis of Echo Signature and Target Strength of a Realistically Modelled Ship Wake for a Generic Forward Looking Active Sonar

NARCIS (Netherlands)

Schippers, P.

2009-01-01

The acoustic modelling in TNO’s ALMOST (=Acoustic Loss Model for Operational Studies and Tasks) uses a bubble migration model as realistic input for wake modelling. The modelled bubble cloud represents the actual ship wake. Ship hull, propeller and bow wave are the main generators of bubbles in the

Free-weight resistance exercise on pulse wave reflection and arterial stiffness between sexes in young, resistance-trained adults.

Science.gov (United States)

Kingsley, J Derek; Tai, Yu Lun; Mayo, Xian; Glasgow, Alaina; Marshall, Erica

2017-09-01

We sought to determine the sex-specific effects of an acute bout of free-weight resistance exercise (RE) on pulse wave reflection (aortic blood pressures, augmentation index (AIx), AIx at 75 bpm (AIx@75), augmentation pressure (AP), time of the reflected wave (Tr), subendocardial viability ratio (SEVR)), and aortic arterial stiffness in resistance-trained individuals. Resistance-trained men (n = 14) and women (n = 12) volunteered to participate in the study. Measurements were taken in the supine position at rest, and 10 minutes after 3 sets of 10 repetitions at 75% 1-repetition maximum on the squat, bench press, and deadlift. A 2 × 2 × 2 ANOVA was used to analyse the effects of sex (men, women) across condition (RE, control) and time (rest, recovery). There were no differences between sexes across conditions and time. There was no effect of the RE on brachial or aortic blood pressures. There were significant condition × time interactions for AIx (rest: 12.1 ± 7.9%; recovery: 19.9 ± 10.5%, p = .003), AIx@75 (rest: 5.3 ± 7.9%; recovery: 24.5 ± 14.3%, p = .0001), AP (rest: 4.9 ± 2.8 mmHg; recovery: 8.3 ± 6.0 mmHg, p = .004), and aortic arterial stiffness (rest: 5.3 ± 0.6 ms; recovery: 5.9 ± 0.7 ms, p = .02) with significant increases during recovery from the acute RE. There was also a significant condition × time for time of the reflected wave (rest: 150 ± 7 ms; recovery: 147 ± 9 ms, p = .02) and SEVR (rest: 147 ± 17%; recovery: 83 ± 24%, p = .0001) such that they were reduced during recovery from the acute RE compared to the control. These data suggest that an acute bout of RE increases AIx, AIx@75, and aortic arterial stiffness similarly between men and women without significantly altering aortic blood pressures.

Quantifying wave propagation over a corrugated metal using 5 dBi antennas

CSIR Research Space (South Africa)

Nkosi, MC

2015-09-01

Full Text Available corrugated metal of a shipping container and also in a free space. The free space measurement is used as a reference point to study the influence of the metal on the wave propagation. The transmission coefficient measured over the shipping container...

Safety Analysis Report for Packaging (SARP) of the Oak Ridge National Laboratory Foamglas Shipping Container

International Nuclear Information System (INIS)

Klima, B.B.; Shappert, L.B.; Seagren, R.D.; Box, W.D.

1978-05-01

An analytical evaluation of the Oak Ridge National Laboratory (ORNL) Foamglas Shipping Container was made to demonstrate its compliance with the regulations governing offsite radioactive material shipping packages. The evaluation encompassed five primary categories: structural integrity, thermal resistance, radiation shielding, nuclear criticality safety, and quality assurance. The results of the evaluation show that the container complies with the applicable regulations

LCA-ship. Design tool for energy efficient ships. A Life Cycle Analysis Program for Ships. Final report

Energy Technology Data Exchange (ETDEWEB)

Jiven, Karl; Sjoebris, Anders [MariTerm AB, Goeteborg (Sweden); Nilsson, Maria [Lund Univ. (Sweden). Stiftelsen TEM; Ellis, Joanne; Traegaardh, Peter; Nordstroem, Malin [SSPA Sweden AB, Goeteborg (Sweden)

2004-05-01

In order to make it easier to include aspects during ship design that will improve environmental performance, general methods for life cycle calculations and a prototype tool for LCA calculations of ships and marine transportation have been developed. The base of the life cycle analyses is a comprehensive set of life cycle data that was collected for the materials and consumables used in ship construction and vessel operations. The computer tool developed makes it possible to quickly and simply specify (and calculate) the use of consumables over the vessel's life time cycle. Special effort has been made to allow the tool to be used for different types of vessels and sea transport. The main result from the project is the computer tool LCA ship, which incorporates collected and developed life cycle data for some of the most important materials and consumables used in ships and their operation. The computer application also contains a module for propulsion power calculations and a module for defining and optimising the energy system onboard the vessel. The tool itself is described in more detail in the Computer application manual. The input to the application should, as much as possible, be the kind of information that is normally found in a shipping company concerning vessel data and vessel movements. It all starts with defining the ship to be analysed and continues with defining how the ship is used over the lifetime. The tool contains compiled and processed background information about specific materials and processes (LCA data) connected to shipping operations. The LCA data is included in the tool in a processed form. LCA data for steel will for example include the environmental load from the steel production, the process to build the steel structure of the ship, the scrapping and the recycling phase. To be able to calculate the environmental load from the use of steel the total amount of steel used over the life cycle of the ship is also needed. The

Introduction of anti-rolling active vertical fin and its application to maneuverability for displacement-type super high speed ship. 2nd Report.; Haisuiryogata chokosokusen no yokoyure seishiyo active suichoku fin no donyu to sojuseieno oyo

Energy Technology Data Exchange (ETDEWEB)

Hirayama, T; Saito, Y [Yokohama National University, Yokohama (Japan). Faculty of Engineering; Niihara, Y [Ishikawajima-Harima Heavy Industries Co. Ltd., Tokyo (Japan)

1997-12-31

Discussed herein are the effects of vertical fin projecting downwards from the bottom of a displacement-type superhigh-speed ship, installed to improve its transverse stability and turning ability. The system for simultaneously controlling rudder and vertical fin by the optimum regulator was studied for maneuverability in directional following waves and smooth water, and maneuverability was simulated numerically. A ship is greatly rolled and sloped when running in waves. It is found that the vertical fin shows a high anti-rolling effect when the ship runs straight. The optimum regulator greatly improves maneuverability in waves, reducing rolling by 92%. Increased rolling with the vertical fin, observed in the previous study in directional following waves, is found to be due to the rudder. The optimum position of the fin is determined to control transverse sloping of a turning ship in a superhigh-speed region. 21 refs., 12 figs., 4 tabs.

Introduction of anti-rolling active vertical fin and its application to maneuverability for displacement-type super high speed ship. 2nd Report.; Haisuiryogata chokosokusen no yokoyure seishiyo active suichoku fin no donyu to sojuseieno oyo

Energy Technology Data Exchange (ETDEWEB)

Hirayama, T.; Saito, Y. [Yokohama National University, Yokohama (Japan). Faculty of Engineering; Niihara, Y. [Ishikawajima-Harima Heavy Industries Co. Ltd., Tokyo (Japan)

1996-12-31

Discussed herein are the effects of vertical fin projecting downwards from the bottom of a displacement-type superhigh-speed ship, installed to improve its transverse stability and turning ability. The system for simultaneously controlling rudder and vertical fin by the optimum regulator was studied for maneuverability in directional following waves and smooth water, and maneuverability was simulated numerically. A ship is greatly rolled and sloped when running in waves. It is found that the vertical fin shows a high anti-rolling effect when the ship runs straight. The optimum regulator greatly improves maneuverability in waves, reducing rolling by 92%. Increased rolling with the vertical fin, observed in the previous study in directional following waves, is found to be due to the rudder. The optimum position of the fin is determined to control transverse sloping of a turning ship in a superhigh-speed region. 21 refs., 12 figs., 4 tabs.

Effect of attenuation correction on surface amplitude distribution of wind waves

Digital Repository Service at National Institute of Oceanography (India)

Varkey, M.J.

Some selected wave profiles recorded using a ship borne wave recorder are analysed to study the effect of attenuation correction on the distribution of the surface amplitudes. A new spectral width parameter is defined to account for wide band...

Effect of ship locking on sediment oxygen uptake in impounded rivers

DEFF Research Database (Denmark)

Lorke, A.; McGinnis, D. F.; Maeck, A.

2012-01-01

In the majority of large river systems, flow is regulated and/or otherwise affected by operational and management activities, such as ship locking. The effect of lock operation on sediment-water oxygen fluxes was studied within a 12.9 km long impoundment at the Saar River (Germany) using eddy....... Additional means by which the oxygen budget of the impoundment is affected by lock-induced flow variations are discussed. Citation: Lorke, A., D. F. McGinnis, A. Maeck, and H. Fischer (2012), Effect of ship locking on sediment oxygen uptake in impounded rivers, Water Resour. Res., 48, W12514, doi: 10....... These wave-induced flow variations cause variations in sediment-water oxygen fluxes. While the mean flux during time periods without lock operation was 0.5 +/- 0.1 g m(-2) d(-1), it increased by about a factor of 2 to 1.0 +/- 0.5 g m(-2) d(-1) within time periods with ship locking. Following the daily...

Surface waves on currents with arbitrary vertical shear

Science.gov (United States)

Smeltzer, Benjamin K.; Ellingsen, Simen Å.

2017-04-01

We study dispersion properties of linear surface gravity waves propagating in an arbitrary direction atop a current profile of depth-varying magnitude using a piecewise linear approximation and develop a robust numerical framework for practical calculation. The method has been much used in the past for the case of waves propagating along the same axis as the background current, and we herein extend and apply it to problems with an arbitrary angle between the wave propagation and current directions. Being valid for all wavelengths without loss of accuracy, the scheme is particularly well suited to solve problems involving a broad range of wave vectors, such as ship waves and Cauchy-Poisson initial value problems. We examine the group and phase velocities over different wavelength regimes and current profiles, highlighting characteristics due to the depth-variable vorticity. We show an example application to ship waves on an arbitrary current profile and demonstrate qualitative differences in the wake patterns between concave down and concave up profiles when compared to a constant shear profile with equal depth-averaged vorticity. We also discuss the nature of additional solutions to the dispersion relation when using the piecewise-linear model. These are vorticity waves, drifting vortical structures which are artifacts of the piecewise model. They are absent for a smooth profile and are spurious in the present context.

Conclusions from collision examinations for nuclear merchant ships in the FRG

International Nuclear Information System (INIS)

Woisin, G.

1978-01-01

In Germany model tests have been performed for the utilization of a resisting type barrier instead of an energy absorbing type barrier, the latter used in nuclear merchant ships up to now only. After reviewing the model technique the results of nine tests with the new barrier are discussed. Calculations performed to the newly raised questions of the shock accelerations of the reactor plant and of possible overstressing of the hull are reported. The new design has many advantages with respect to safety and to the arrangement of a reactor plant in a ship too. Some questions partly remain unanswered at the moment concerning oblique collisions to the ends of the barrier and the possible effects of bulk cargo in holds close to the bow in striking ships of smaller size

Experimental Verification of a Global Exponentially Stable Nonlinear Wave Encounter Frequency Estimator

DEFF Research Database (Denmark)

Belleter, Dennis J.W.; Galeazzi, Roberto; Fossen, Thor Inge

2015-01-01

towing tank experiments using a container ship scale model. The estimates for both regular and irregular waves confirm the results. Finally, the estimator is applied to full-scale data gathered from a container ship operating in the Atlantic Ocean during a storm. Again the theoretical results...

Classification of Ship Routing and Scheduling Problems in Liner Shipping

DEFF Research Database (Denmark)

Kjeldsen, Karina Hjortshøj

2011-01-01

This article provides a classification scheme for ship routing and scheduling problems in liner shipping in line with the current and future operational conditions of the liner shipping industry. Based on the classification, the literature is divided into groups whose main characteristics...

Transformation of a wave energy spectrum from encounter to absolute domain when observing from an advancing ship

DEFF Research Database (Denmark)

Nielsen, Ulrik Dam

2017-01-01

directly in the encounter domain. The encounter domain is that observed from a ship when it advances in a seaway, whereas the absolute domain is that corresponding to making observations from a fixed point in the inertial frame. Spectrum transformation can be uniquely carried out if the ship sails ”against...

Statistical theory of resistive drift-wave turbulence and transport

International Nuclear Information System (INIS)

Hu, G.; Krommes, J.A.; Bowman, J.C.

1997-01-01

Resistive drift-wave turbulence in a slab geometry is studied by statistical closure methods and direct numerical simulations. The two-field Hasegawa endash Wakatani (HW) fluid model, which evolves the electrostatic potential and plasma density self-consistently, is a paradigm for understanding the generic nonlinear behavior of multiple-field plasma turbulence. A gyrokinetic derivation of the HW model is sketched. The recently developed Realizable Markovian Closure (RMC) is applied to the HW model; spectral properties, nonlinear energy transfers, and turbulent transport calculations are discussed. The closure results are also compared to direct numerical simulation results; excellent agreement is found. The transport scaling with the adiabaticity parameter, which measures the strength of the parallel electron resistivity, is analytically derived and understood through weak- and strong-turbulence analyses. No evidence is found to support previous suggestions that coherent structures cause a large depression of saturated transport from its quasilinear value in the hydrodynamic regime of the HW model. Instead, the depression of transport is well explained by the spectral balance equation of the (second-order) statistical closure when account is taken of incoherent noise. copyright 1997 American Institute of Physics

Review of experiments and calculation procedures for ship collision and grounding damage

DEFF Research Database (Denmark)

Liu, Bin; Pedersen, Preben Terndrup; Zhu, Ling

2018-01-01

Abstract The paper presents a review of experiments and calculation procedures for the resistances of ship structural components subjected to impact loadings. The purpose of the paper is to highlight the importance of large-scale collision and grounding experiments and to discuss the technical...... and material characteristics. In recent literature, analytical and numerical calculations provide relatively accurate prediction of the purely plastic responses of ship structures under impact loads, but universal approaches have not been found for fracture predictions. The existing formulae for failure...

Artificial Neural Network-Based Clutter Reduction Systems for Ship Size Estimation in Maritime Radars

Directory of Open Access Journals (Sweden)

M. P. Jarabo-Amores

2010-01-01

Full Text Available The existence of clutter in maritime radars deteriorates the estimation of some physical parameters of the objects detected over the sea surface. For that reason, maritime radars should incorporate efficient clutter reduction techniques. Due to the intrinsic nonlinear dynamic of sea clutter, nonlinear signal processing is needed, what can be achieved by artificial neural networks (ANNs. In this paper, an estimation of the ship size using an ANN-based clutter reduction system followed by a fixed threshold is proposed. High clutter reduction rates are achieved using 1-dimensional (horizontal or vertical integration modes, although inaccurate ship width estimations are achieved. These estimations are improved using a 2-dimensional (rhombus integration mode. The proposed system is compared with a CA-CFAR system, denoting a great performance improvement and a great robustness against changes in sea clutter conditions and ship parameters, independently of the direction of movement of the ocean waves and ships.

Bayesian Estimation of Wave Spectra – Proper Formulation of ABIC

DEFF Research Database (Denmark)

Nielsen, Ulrik Dam

2007-01-01

It is possible to estimate on-site wave spectra using measured ship responses applied to Bayesian Modelling based on two prior information: the wave spectrum must be smooth both directional-wise and frequency-wise. This paper introduces two hyperparameters into Bayesian Modelling and, hence, a pr...

Cyclic Fatigue Resistance of OneShape, HyFlex EDM, WaveOne Gold, and Reciproc Blue Nickel-titanium Instruments.

Science.gov (United States)

Gündoğar, Mustafa; Özyürek, Taha

2017-07-01

The purpose of this study was to compare the cyclic fatigue resistances of Reciproc Blue (VDW, Munich, Germany), HyFlex EDM (Coltene/Whaledent, Altstätten, Switzerland), WaveOne Gold (Dentsply Maillefer, Ballaigues, Switzerland), and OneShape (Micro Mega, Besancon, France) single-file NiTi systems. Thirty Reciproc Blue R25 (25/.08), 30 HyFlex EDM (25/.∼), 30 WaveOne Gold Primary (25/.07), and 30 OneShape (25/.06) instruments were included in this study. All the instruments were rotated in artificial canals, which were made of stainless steel with an inner diameter of 1.5 mm, a 60° angle of curvature, and radii of curvatures of 5 mm until fracture occurred, and the time to fracture was recorded in seconds using a digital chronometer. The data were analyzed statistically using Kruskal-Wallis and post hoc Dunn tests via SPSS 21.0 software (SPSS Inc, Chicago, IL). The statistical significance level was set at 5%. The HyFlex EDM file (3456.33 ± 633.37) file had the statistically highest fatigue resistance, and the OneShape file (1221.63 ± 812.4) had the least fatigue resistance (P  .05) in the mean length of the fractured fragments of the files (P > .05). Within the limitations of the present in vitro study, it was found that cyclic fatigue resistance of HyFlex EDM files was higher than the cyclic fatigue resistances of OneShape, Reciproc Blue, and WaveOne Gold files. Copyright © 2017 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Nuclear merchant ship propulsion

International Nuclear Information System (INIS)

Schroeder, E.; Jager, W.; Schafstall, H.G.

1977-01-01

The operation of about 300 nuclear naval vessels has proven the feasibility of nuclear ship propulsion. Until now six non military ships have been built or are under construction. In the Soviet Union two nuclear icebreakers are in operation, and a third one is under construction. In the western world three prototype merchant ships have been built. Of these ships only the NS OTTO HAHN is in operation and provides valuable experience for future large scale use of nuclear merchant ship propulsion. In many countries studies and plans are made for future nuclear merchant ships. Types of vessels investigated are large containerships, tankers and specialized ships like icebreakers or ice-breaking ships. The future of nuclear merchant ship propulsion depends on three interrelated items: (1) nuclear ship technology; (2) economy of nuclear ship propulsion; (3) legal questions. Nuclear merchant ship technology is based until now on standard ship technology and light water reactor technology. Except for special questions due to the non-stationary type of the plant entirely new problems do not arise. This has been proven by the recent conceptual licensing procedure for a large nuclear containership in Germany. The economics of nuclear propulsion will be under discussion until they are proven by the operation of privately owned lead ships. Unsolved legal questions e.g. in connection with port entry permissions are at present another problem for nuclear shipping. Efforts are made to solve these questions on an international basis. The future development of nuclear energy electricity production in large land based plants will stimulate the employment of smaller units. Any future development of long distance sea transport will have to take this opportunity of a reliable and economic energy supply into account

Estimation of real ship propelling performance by the surface velocity lattice method using model ship flow field data; Mokeisen ryujo data wo mochiita hyomen uzu koshiho ni yoru jissen suishin seino no suitei

Energy Technology Data Exchange (ETDEWEB)

Kai, H; Ikehata, M; Sakai, S [Yokohama National University, Yokohama (Japan). Faculty of Engineering

1997-10-01

This is basically a technique wherein the wing element method is replaced by a surface vortex lattice method. A horseshoe vortex of unknown intensity and source surface of known intensity are distributed on the wing surface and, under conditions that the fluid will not cross the boundary, the intensity of horseshoe vortex circulation is calculated for the solution of the fluid field. For the simulation of a real ship in navigation, the required propeller revolution thrust is determined using the real ship resistance value and real ship thrust reduction factor estimated from a model ship resistance test by extrapolation. The calculation of propeller performance is conducted in the quasi-steady condition using the force of fluid working on one wing for each wing angle (with the wing rotated at the increment of 6 degrees), and the thrust and torque are determined using the averages of values obtained in one cycle. It is found that the torque value is overestimated in a considerable degree in the wing element theory. In the surface vortex lattice method, both thrust and torque values agree with experimental values mostly, and this method is found to be accurate enough as a navigation element calculation tool when many panels are considered. 4 refs., 5 figs., 1 tab.

Nonlinear control of ships minimizing the position tracking errors

Directory of Open Access Journals (Sweden)

Svein P. Berge

1999-07-01

Full Text Available In this paper, a nonlinear tracking controller with integral action for ships is presented. The controller is based on state feedback linearization. Exponential convergence of the vessel-fixed position and velocity errors are proven by using Lyapunov stability theory. Since we only have two control devices, a rudder and a propeller, we choose to control the longship and the sideship position errors to zero while the heading is stabilized indirectly. A Virtual Reference Point (VRP is defined at the bow or ahead of the ship. The VRP is used for tracking control. It is shown that the distance from the center of rotation to the VRP will influence on the stability of the zero dynamics. By selecting the VRP at the bow or even ahead of the bow, the damping in yaw can be increased and the zero dynamics is stabilized. Hence, the heading angle will be less sensitive to wind, currents and waves. The control law is simulated by using a nonlinear model of the Japanese training ship Shiojimaru with excellent results. Wind forces are added to demonstrate the robustness and performance of the integral controller.

Risk Analysis on Ship Wreck and Container Cargo to Ship Navigation

Directory of Open Access Journals (Sweden)

Muhammad Badrus Zaman

2017-03-01

Full Text Available Wreck of a ship is an incident that must be avoided. Ship accidents are generally caused by a several cases, such as human error, natural disaster, technical errors, missed communication, poor condition of the ship, and many more. Ship wreckage have huge impact for ship navigation, environment, economics, and others. Those impact have many disadvantages for the shipowners, and also for environment. For examples the fuel spills that pollute the environment, make disturbance to sailing ship because the track for those navigation is blocked by the ship wreck and their cargo especially on shallow location (<50 m. These research will discuss the effect the container when it is floats on the sea and its interference other ships. The main objective of this study is to present a risk assessment on the environmental impact of the wreck and container cargo. Wrecks on the seabed is likely to pose a risk to passing ships. container and its contents as well as the possibility of refloat, and also their environmental risks emanating from the wreck and container cargo, such as fuels, lubricants, and chemical cargo. Variations scenario is a collision between ships that pass by floating containers. The frequency of refloating container, and the consequences of the passing ship depends on several factors, which will be the subject of research. However, because of the frequency of refloating containers is unlikely, then the risk is low and does not pose a danger to navigation. These risk assessment using risk matrix 5x5 which is the combined value of the frequency and consequences of the incident. The results of this study indicate the level of risk, whether the risk is accepted, not accepted or received by considering the costs and benefits (ALARP. To consequence, there are two parameters which energy is absorbed and the penetration occurs. The absorbed energy is divided into two, namely the energy absorbed by ship and the energy absorbed by containers. In this

HF Surface Wave Radar Operation in Adverse Conditions

National Research Council Canada - National Science Library

Ponsford, Anthony M; Dizaji, Reza M; McKerracher, Richard

2005-01-01

...) system based on HF Surface Wave Radar (HFSWR). the primary objective behind the programme was to demonstrate the capability of HFSWR to continuously detect and track surface targets (ships and icebergs...

Influence of Surge Motion on the Probability of Parametric Roll in a Stationary Sea State

DEFF Research Database (Denmark)

Jensen, Jørgen Juncher; Vidic-Perunovic, Jelena; Pedersen, Preben Terndrup

2007-01-01

A typical parametric roll scenario for a ship in head waves implies that the roll motion is coupled with vertical motion of the vessel. The added resistance of the ship is increased when the bow pitches down in a wave crest. As a consequence, the ship speed is slowed down and, hence, the roll...... resonance condition might be changed. In an attempt to study the influence of this speed variation in waves on parametric roll, the procedure for estimation of probability of parametric roll by Jensen and Pedersen (2006) has been extended to account for the surge motion of the vessel....

Buckling of Ship Structures

CERN Document Server

Shama, Mohamed

2013-01-01

Buckling of Ship Structures presents a comprehensive analysis of the buckling problem of ship structural members. A full analysis of the various types of loadings and stresses imposed on ship plating and primary and secondary structural members is given. The main causes and consequences of the buckling mode of failure of ship structure and the methods commonly used to control buckling failure are clarified. This book contains the main equations required to determine the critical buckling stresses for both ship plating and the primary and secondary stiffening structural members. The critical buckling stresses are given for ship plating subjected to the induced various types of loadings and having the most common boundary conditions encountered in ship structures.  The text bridges the gap existing in most books covering the subject of buckling of ship structures in the classical analytical format, by putting the emphasis on the practical methods required to ensure safety against buckling of ship structur...

Ship Detection Based on Multiple Features in Random Forest Model for Hyperspectral Images

Science.gov (United States)

Li, N.; Ding, L.; Zhao, H.; Shi, J.; Wang, D.; Gong, X.

2018-04-01

A novel method for detecting ships which aim to make full use of both the spatial and spectral information from hyperspectral images is proposed. Firstly, the band which is high signal-noise ratio in the range of near infrared or short-wave infrared spectrum, is used to segment land and sea on Otsu threshold segmentation method. Secondly, multiple features that include spectral and texture features are extracted from hyperspectral images. Principal components analysis (PCA) is used to extract spectral features, the Grey Level Co-occurrence Matrix (GLCM) is used to extract texture features. Finally, Random Forest (RF) model is introduced to detect ships based on the extracted features. To illustrate the effectiveness of the method, we carry out experiments over the EO-1 data by comparing single feature and different multiple features. Compared with the traditional single feature method and Support Vector Machine (SVM) model, the proposed method can stably achieve the target detection of ships under complex background and can effectively improve the detection accuracy of ships.

Viking FellowSHIP: Norwegian hydrogen ship on the right course

International Nuclear Information System (INIS)

Larssen-Aas, Kari

2006-01-01

In the future fuel cells will change the world of shipping's economical conditions, and environmental effects from this industry. A new model of a hydrogen fuelled ship was presented at the ONS exhibition in Stavanger 2006. The technology may revolutionize the shipping industry. A brief description of the project is presented (ml)

Safety of nuclear ships

International Nuclear Information System (INIS)

1978-01-01

Interest in the utilization of nuclear steam supply systems for merchant ships and icebreakers has recently increased considerably due to the sharp rise in oil prices and the continuing trend towards larger and faster merchant ships. Canada, for example, is considering construction of an icebreaker in the near future. On the other hand, an accident which could result in serious damage to or the sinking of a nuclear ship is potentially far more dangerous to the general public than a similar accident with a conventional ship. Therefore, it was very important to evaluate in an international forum the safety of nuclear ships in the light of our contemporary safety philosophy, taking into account the results of cumulative operating experience with nuclear ships in operation. The philosophy and safety requirement for land-based nuclear installations were outlined because of many common features for both land-based nuclear installations and nuclear ships. Nevertheless, essential specific safety requirements for nuclear ships must always be considered, and the work on safety problems for nuclear ships sponsored by the NEA was regarded as an important step towards developing an international code of practice by IMCO on the safety of nuclear merchant ships. One session was devoted to the quantitative assessment of nuclear ship safety. The probability technique of an accident risk assessment for nuclear power plants is well known and widely used. Its modification, to make it applicable to nuclear propelled merchant ships, was discussed in some papers. Mathematical models for describing various postulated accidents with nuclear ships were developed and reported by several speakers. Several papers discussed a loss-of-coolant accident (LOCA) with nuclear steam supply systems of nuclear ships and engineering design features to prevent a radioactive effluence after LOCA. Other types of postulated accidents with reactors and systems in static and dynamic conditions were also

Observational and Dynamical Wave Climatologies. VOS vs Satellite Data

Science.gov (United States)

Grigorieva, Victoria; Badulin, Sergei; Chernyshova, Anna

2013-04-01

The understanding physics of wind-driven waves is crucially important for fundamental science and practical applications. This is why experimental efforts are targeted at both getting reliable information on sea state and elaborating effective tools of the sea wave forecasting. The global Visual Wave Observations and satellite data from the GLOBWAVE project of the European Space Agency are analyzed in the context of these two viewpoints. Within the first "observational" aspect we re-analyze conventional climatologies of all basic wave parameters for the last decades [5]. An alternative "dynamical" climatology is introduced as a tool of prediction of dynamical features of sea waves on global scales. The features of wave dynamics are studied in terms of one-parametric dependencies of wave heights on wave periods following the theoretical concept of self-similar wind-driven seas [3, 1, 4] and recently proposed approach to analysis of Voluntary Observing Ship (VOS) data [2]. Traditional "observational" climatologies based on VOS and satellite data collections demonstrate extremely consistent pictures for significant wave heights and dominant periods. On the other hand, collocated satellite and VOS data show significant differences in wave heights, wind speeds and, especially, in wave periods. Uncertainties of visual wave observations can explain these differences only partially. We see the key reason of this inconsistency in the methods of satellite data processing which are based on formal application of data interpolation methods rather than on up-to-date physics of wind-driven waves. The problem is considered within the alternative climatology approach where dynamical criteria of wave height-to-period linkage are used for retrieving wave periods and constructing physically consistent dynamical climatology. The key dynamical parameter - exponent R of one-parametric dependence Hs ~ TR shows dramatically less pronounced latitudinal dependence as compared to observed Hs

Millimeter wave surface resistance of grain-aligned Y1Ba2Cu3Ox bulk material

International Nuclear Information System (INIS)

Wosik, J.; Kranenburg, R.A.; Wolfe, J.C.; Selvamanickam, V.; Salama, K.

1991-01-01

We report measurements of the millimeter wave surface resistance of grain-aligned YBa 2 Cu 3 O x bulk material grown by a liquid phase process. The measurements were performed by replacing the endplate of a TE 011 cylindrical copper cavity with the superconducting sample. Surface resistance was measured for samples with surfaces oriented perpendicular and parallel to the c-axis of the grains. We show that, for the parallel configuration, the surface resistance at 77 K and 80 GHz is typically near 100 mΩ. For a very well-aligned sample with a very low density of Y 2 BaCuO y precipitates, measured in the perpendicular configuration, the transition width (10%--90%) is about 2 K and the surface resistance is less than 50 mΩ at 88 K. The effect of microstructure on surface resistance is discussed

Numerical Simulation of Galvanic Corrosion Caused by Shaft Grounding Systems in Steel Ship Hulls

National Research Council Canada - National Science Library

Wang, Y

2005-01-01

The shaft grounding systems used on board HMC ships have substantially reduced the shaft-to-hull resistance and, thus, improved the performance of the shipboard impressed current cathodic protection (ICCP) system...

Modeling of Ship Roll Dynamics and Its Coupling with Heave and Pitch

Directory of Open Access Journals (Sweden)

R. A. Ibrahim

2010-01-01

Full Text Available In order to study the dynamic behavior of ships navigating in severe environmental conditions it is imperative to develop their governing equations of motion taking into account the inherent nonlinearity of large-amplitude ship motion. The purpose of this paper is to present the coupled nonlinear equations of motion in heave, roll, and pitch based on physical grounds. The ingredients of the formulation are comprised of three main components. These are the inertia forces and moments, restoring forces and moments, and damping forces and moments with an emphasis to the roll damping moment. In the formulation of the restoring forces and moments, the influence of large-amplitude ship motions will be considered together with ocean wave loads. The special cases of coupled roll-pitch and purely roll equations of motion are obtained from the general formulation. The paper includes an assessment of roll stochastic stability and probabilistic approaches used to estimate the probability of capsizing and parameter identification.

Shielding repair and comprehensive safety inspection of the nuclear-powered ship Mutsu

International Nuclear Information System (INIS)

Takada, Etsuo

1982-01-01

Eight years after the radiation leakage accident, the nuclear-powered ship Mutsu returned again to its home port Ominato. During the period, for four years, the n.s. Mutsu was subjected to shielding repair and comprehensive inspection at Sasebo port. In the future, the ship will start on experimental navigation after its functional and power-up tests. The works of shielding repair and the comprehensive inspection with subsequent repair are described in technical aspects. The basic policy of the repair was two points, i.e. the usage of shielding materials excellent in shielding capacity, less in radioactivation and enduring operating temperature, and structural strength resisting ship-hull acceleration, shock and vibration, enabling easy maintenance and inspection. Comprehensive inspection was made on not only machinery integrity but also the design itself. (Mori, K.)

Robust H∞ Control of Neutral System with Time-Delay for Dynamic Positioning Ships

Directory of Open Access Journals (Sweden)

Dawei Zhao

2015-01-01

Full Text Available Due to the input time-delay existing in most thrust systems of the ships, the robust H∞ controller is designed for the ship dynamic positioning (DP system with time-delay. The input delay system is turned to a neutral time-delay system by a state-derivative control law. The less conservative result is derived for the neutral system with state-derivative feedback by the delay-decomposition approach and linear matrix inequality (LMI. Finally, the numerical simulations demonstrate the asymptotic stability and robustness of the controller and verify that the designed DP controller is effective in the varying environment disturbances of wind, waves, and ocean currents.

Hydrothermal Synthesis of Nanooctahedra MnFe₂O₄ onto the Wood Surface with Soft Magnetism, Fire Resistance and Electromagnetic Wave Absorption.

Science.gov (United States)

Wang, Hanwei; Yao, Qiufang; Wang, Chao; Ma, Zhongqing; Sun, Qingfeng; Fan, Bitao; Jin, Chunde; Chen, Yipeng

2017-05-23

In this study, nanooctahedra MnFe₂O₄ were successfully deposited on a wood surface via a low hydrothermal treatment by hydrogen bonding interactions. As-prepared MnFe₂O₄/wood composite (MW) had superior performance of soft magnetism, fire resistance and electromagnetic wave absorption. Among them, small hysteresis loops and low coercivity (magnetization-field curve of MW with saturation magnetization of 28.24 emu/g, indicating its excellent soft magnetism. The MW also exhibited a good fire-resistant property due to its initial burning time at 20 s; while only 6 s for the untreated wood (UW) in combustion experiments. Additionally, this composite revealed good electromagnetic wave absorption with a minimum reflection loss of -9.3 dB at 16.48 GHz. Therefore, the MW has great potential in the fields of special decoration and indoor electromagnetic wave absorbers.

Recent situations around nuclear ships

International Nuclear Information System (INIS)

Mizuno, Hiroshi

1978-01-01

The philosophy when the safety standard for nuclear ships is drawn up and the international rules specifically for nuclear ships are summarized. As for the safety standard for nuclear ships, the safety requirements for ordinary ships, for the ships transporting nuclear reactors, for ordinary nuclear reactors, and for the reactors moving around the seas must be included. As for the international rules for nuclear ships, there are chapter 8 ''Nuclear ships'' in the International Convention on the Safety of Life at Sea, 1960 and 1974, and Safety Consideration in the Use of Ports and Approaches by Nuclear Merchant Ships. Also there are national rules and standards in Japan and foreign countries. One of the means to explore the practicality of nuclear ships is the investigation of the economy. At this time, the social merits and demerits of nuclear ships must be compared with conventional ships by taking total expenses into account without omission. When oil is depleted, the age of nuclear ships will not necessarily begin, and the will be still some competitors. The investigations concerning the economy of nuclear ships have been carried out in various countries. The present state of the development of nuclear ships in Japan and foreign countries is explained. Many conferences and symposia have been held concerning nuclear ships, and those held recently are enumerated. The realization of nuclear ship age cannot be anticipated from existing papers and shipbuilding projects. (Kako, I.)

Shipping Information Pipeline

DEFF Research Database (Denmark)

Jensen, Thomas

to creating a more efficient shipping industry, and a number of critical issues are identified. These include that shipments depend on shipping information, that shipments often are delayed due to issues with documentation, that EDI messages account for only a minor part of the needed information......This thesis applies theoretical perspectives from the Information Systems (IS) research field to propose how Information Technology (IT) can improve containerized shipping. This question is addressed by developing a set of design principles for an information infrastructure for sharing shipping...... information named the Shipping Information Pipeline (SIP). Review of the literature revealed that IS research prescribed a set of meta-design principles, including digitalization and digital collaboration by implementation of Inter-Organizational Systems based on Electronic Data Interchange (EDI) messages...

A numerical study on ship-ship interaction in shallow and restricted waterway

Directory of Open Access Journals (Sweden)

Sungwook Lee

2015-09-01

Full Text Available In the present study, a numerical prediction method on the hydrodynamic interaction force and moment between two ships in shallow and restricted waterway is presented. Especially, the present study proposes a methodology to overcome the limitation of the two dimensional perturbation method which is related to the moored-passing ship interaction. The validation study was performed and compared with the experiment, firstly. Afterward, in order to propose a methodology in terms with the moored-passing ship interaction, further studies were performed for the moored-passing ship case with a Reynolds Averaged Navier-Stokes (RANS calculation which is using OpenFOAM with Arbitrary Coupled Mesh Interface (ACMI technique and compared with the experiment result. Finally, the present study proposes a guide to apply the two dimensional perturbation method to the moored-passing ship interaction. In addition, it presents a possibility that the RANS calculation with ACMI can applied to the ship-ship interaction without using a overset moving grid technique.

Nuclear ship engineering simulator

International Nuclear Information System (INIS)

Itoh, Yasuyoshi; Kusunoki, Tsuyoshi; Hashidate, Koji

1991-01-01

The nuclear ship engineering simulator, which analyzes overall system response of nuclear ship numerically, is now being developed by JAERI as an advanced design tool with the latest computer technology in software and hardware. The development of the nuclear ship engineering simulator aims at grasping characteristics of a reactor plant under the situation generated by the combination of ocean, a ship hull and a reactor. The data from various tests with the nuclear ship 'MUTSU' will be used for this simulator to modulate and verify its functions of reproducing realistic response of nuclear ship, and then the simulator will be utilized for the research and development of advanced marine reactors. (author)

Millimeter wave surface resistance of grain-aligned Y1Ba2Cu3O(x) bulk material

International Nuclear Information System (INIS)

Wosik, J.; Kranenburg, R.A.; Wolfe, J.C.; Selvamanickam, V.; Salama, K.

1990-04-01

Measurements are reported of the millimeter-wave surface resistance of grain-aligned YBa2Cu3O(x) bulk material grown by a liquid-phase process. The measurements were performed by replacing the endplate of a TE(011) cylindrical copper cavity with the superconducting sample. Surface resistance was measured for samples with surfaces oriented perpendicular and parallel to the c-axis of the grains. For the parallel configuration, the surface resistance at 77 K and 80 GHz is given. For a very well-aligned sample with a very low density of Y2BaCuO(y) precipitates, measured in the perpendicular configuration, the transition width (10-90 percent) is about 2 K and the surface resistance is derived at 88 K. The effect of microstructure on surface resistance is discussed. 19 refs

Use of timber in shipbuilding industry: Identification and analysis of timber from shipwrecks off Goa coast, India

Digital Repository Service at National Institute of Oceanography (India)

Tripati, S.; Sujatha, M.; Rao, R.V.; Rao, K.S.

for construction of sea going ships, which could resist the action of waves, currents, marine biofouling, above all, it would bring joy and wealth. In order to locate the remains of ships, cargo and their history, maritime archaeological explorations were carried...

Crushing Strength of Ship Structures

DEFF Research Database (Denmark)

Cerup-Simonsen, Bo; Abramowicz, W.; Høstgaard-Brene, C.N.S.

1999-01-01

The crushing response of ship structures is of primary importance to the designers and practicing engineers concerned with accidental loading and accident reconstruction of marine vehicles. Ship to-ship collisions, ship-harbor infrastructure interaction or ship-offshore structure interaction are ...

Rogue Waves in the Ocean

Science.gov (United States)

Waseda, Takuji

2010-03-01

Giant episodic ocean waves that suddenly soar like a wall of water out of an otherwise calm sea are not just a legend. Such waves—which in the past have been called “abnormal,” “exceptional,” “extreme,” and even “vicious killer” waves—are now commonly known as “rogue waves” or “freak waves.” These waves have sunk or severely damaged 22 supercarriers in the world and caused the loss of more than 500 lives in the past 40 years. The largest wave registered by reliable instruments reached 30 meters in height, and the largest wave recorded by visual observation reached about 34 meters, equivalent to the height of an eight-story building. Tales of seafarers from Christopher Columbus to the passengers of luxury cruise ships had long been undervalued by scientists, but in the past 10 or so years, those historical notes and modern testimonies have been scientifically dissected to reveal the nature of these monster waves.

Development of the nuclear ship MUTSU spent fuel shipping cask

International Nuclear Information System (INIS)

Ishizuka, M.; Umeda, M.; Nawata, Y.; Sato, H.; Honami, M.; Nomura, T.; Ohashi, M.; Higashino, A.

1989-01-01

After the planned trial voyage (4700 MWD/MTU) of the nuclear ship MUTSU in 1990, her spent fuel assemblies, initially made of two types of enriched UO 2 (3.2wt% and 4.4wt%), will be transferred to the reprocessing plant soon after cooling down in the ship reactor for more than one year. For transportation, the MUTSU spent fuel shipping casks will be used. Prior to transportation to the reprocessing plant, the cooled spent fuel assemblies will be removed from the reactor to the shipping casks and housed at the spent fuel storage facility on site. In designing the MUTSU spent fuel shipping cask, considerations were given to make the leak-tightness and integrity of the cask confirmable during storage. The development of the cask and the storage function demonstration test were performed by Japan Atomic Energy Research Institute (JAERI) and Mitsubishi Heavy Industries, Ltd. (MHI). One prototype cask for the storage demonstration test and licensed thirty-five casks were manufactured between 1987 and 1988

Development of a Shipboard Remote Control and Telemetry Experimental System for Large-Scale Model's Motions and Loads Measurement in Realistic Sea Waves.

Science.gov (United States)

Jiao, Jialong; Ren, Huilong; Adenya, Christiaan Adika; Chen, Chaohe

2017-10-29

Wave-induced motion and load responses are important criteria for ship performance evaluation. Physical experiments have long been an indispensable tool in the predictions of ship's navigation state, speed, motions, accelerations, sectional loads and wave impact pressure. Currently, majority of the experiments are conducted in laboratory tank environment, where the wave environments are different from the realistic sea waves. In this paper, a laboratory tank testing system for ship motions and loads measurement is reviewed and reported first. Then, a novel large-scale model measurement technique is developed based on the laboratory testing foundations to obtain accurate motion and load responses of ships in realistic sea conditions. For this purpose, a suite of advanced remote control and telemetry experimental system was developed in-house to allow for the implementation of large-scale model seakeeping measurement at sea. The experimental system includes a series of technique sensors, e.g., the Global Position System/Inertial Navigation System (GPS/INS) module, course top, optical fiber sensors, strain gauges, pressure sensors and accelerometers. The developed measurement system was tested by field experiments in coastal seas, which indicates that the proposed large-scale model testing scheme is capable and feasible. Meaningful data including ocean environment parameters, ship navigation state, motions and loads were obtained through the sea trial campaign.

Ship Vibrations

DEFF Research Database (Denmark)

Sørensen, Herman

1997-01-01

Methods for calculating natural frequencies for ship hulls and for plates and panels.Evaluation of the risk for inconvenient vibrations on board......Methods for calculating natural frequencies for ship hulls and for plates and panels.Evaluation of the risk for inconvenient vibrations on board...

Influence of standing-wave fields on the laser damage resistance of dielectric films

International Nuclear Information System (INIS)

Newnam, B.E.; Gill, D.H.; Faulkner, G.

1973-01-01

The influence of standing-wave electric fields on the damage resistance of dielectric thin films was evaluated for the case of 30-ps laser pulses at 1.06 μm. Single-layer films of TiO 2 , ZrO 2 , SiO 2 , and MgF 2 were deposited by state-of-the-art electron-gun evaporation on BK-7 glass substrates with uniform surface preparation. The film thicknesses ranged from one to five quarter-wave increments. The thresholds for TiO 2 films of odd quarter-wave thickness were greater than for even multiples which correlated well with the calculated internal maximum electric fields. Threshold variations for ZrO 2 films were apparent but not as distinctly periodic with film thickness. Negligible variations were obtained for SiO 2 films, again correlating with electric-field calculations. Results of additional tests allowed comparisons of thresholds for 1) back-and front-surface films for normal incidence; 2) S- and P-polarized radiation at an incidence angle of 60 0 ; and 3) circular and linear polarizations for normal incidence. The thresholds were compared with calculated standing-wave field patterns at various locations in the films. A correlation was generally found between the internal field maxima and the thresholds, but in a few coatings, defects apparently decreased or prevented any correlation. (auth)

Millimeter wave surface resistance of grain-aligned Y1Ba2Cu3O(x) bulk material

Science.gov (United States)

Wosik, J.; Kranenburg, R. A.; Wolfe, J. C.; Selvamanickam, V.; Salama, K.

1991-01-01

Measurements of the millimeter wave surface resistance of grain-aligned YBa2Cu3O(x) bulk material grown by a liquid phase process are reported. The measurements were performed by replacing the endplate of a TE011 cylindrical copper cavity with the superconducting sample. Surface resistance was measured for samples with surfaces oriented perpendicular and parallel to the c-axis of the grains. It is shown that, for the parallel configuration, the surface resistance at 77 K and 80 GHz is typically near 100 milliohms. For a very well-aligned sample with a very low density of Y2BaCuO(y) precipitates, measured in the perpendicular configuration, the transition width (10-90 percent) is about 2 K, and the surface resistance is less than 50 milliohms at 88 K. The effect of microstructure on surface resistance is discussed.

Who greens the waves? Changing authority in the environmental governance of shipping and offshore oil and gas production

International Nuclear Information System (INIS)

Van Leeuwen, J.

2010-01-01

The marine environment is under serious pressure from human activities. The transboundary and large-scale nature of these threats require cooperation between states, and between states, industries and NGOs. Marine governance therefore becomes a breeding ground for innovation: multi-level and multi-actor governance and changing spheres of authority. This book applies the concept 'spheres of authority' to investigate the nature of these innovations in governing shipping and offshore oil and gas production. In the environmental governance of shipping, authority is shifting from states that own ships to states that own ports. The environmental governance of offshore oil and gas production shows a shared authority for developing and implementing policies between state and industry, but not a diminishing authority of the state.

Safety Analysis Report for Packaging (SARP) of the Oak Ridge National Laboratory Shipping Cask D-38. Revision 1

International Nuclear Information System (INIS)

Box, W.D.; Shappert, L.B.; Seagren, R.D.; Watson, C.D.; Hammond, C.R.; Klima, B.B.

1979-09-01

An analytical evaluation of the Oak Ridge National Laboratory Shipping Cask D-38 (solids shipments) was made to demonstrate its compliance with the regulations governing off-site radioactive material shipping packages. The evaluation encompassed five primary categories: structural integrity, thermal resistance, radiation shielding, nuclear criticality safety, and quality assurance. The results of the evaluation show that the cask complies with the applicable regulations

Safety Analysis Report for Packaging (SARP) of the Oak Ridge National Laboratory Shipping Cask D-38. Revision 1

Energy Technology Data Exchange (ETDEWEB)

Box, W.D.; Shappert, L.B.; Seagren, R.D.; Watson, C.D.; Hammond, C.R.; Klima, B.B.

1979-09-01

An analytical evaluation of the Oak Ridge National Laboratory Shipping Cask D-38 (solids shipments) was made to demonstrate its compliance with the regulations governing off-site radioactive material shipping packages. The evaluation encompassed five primary categories: structural integrity, thermal resistance, radiation shielding, nuclear criticality safety, and quality assurance. The results of the evaluation show that the cask complies with the applicable regulations.

Recycling of merchant ships

Directory of Open Access Journals (Sweden)

Magdalena Klopott

2013-12-01

Full Text Available The article briefly outlines the issues concerning ship recycling. It highlights ships' high value as sources of steel scrap and non-ferrous metals, without omitting the fact that they also contain a range of hazardous substances. Moreover, the article also focuses on basic ship demolition methods and their environmental impact, as well as emphasizes the importance of “design for ship recycling” philosophy.

Use of non-quarter-wave designs to increase the damage resistance of reflectors at 532 and 1064 nanometers

International Nuclear Information System (INIS)

Gill, D.H.; Newnam, B.E.; McLeod, J.

1977-01-01

The damage resistance of multilayer dielectric laser reflectors has been increased by using non-quarter-wave thicknesses for the top few layers. These designs minimize the standing-wave electric field in the high-index layers, which are generally the weaker layers. Algebraic equations have been derived for optimum film thicknesses and for the resulting peak electric fields. Five sets of reflectors for 532 and 1064 nm were fabricated according to these designs by two vendors using two different material combinations. Each set contained one reflector of standard all-quarter-wave design and three reflectors each with a different number of modified layers. The damage thresholds of the modified designs were found to be higher than the all-quarter-wave designs, in some cases by a factor greater than 2. The damage thresholds have been analyzed and explained in terms of standing-wave electric field patterns

A Study of Stranding of Juvenile Salmon by Ship Wakes Along the Lower Columbia River Using a Before-and-After Design: Before-Phase Results

Energy Technology Data Exchange (ETDEWEB)

Pearson, Walter H.; Skalski, J R.; Sobocinski, Kathryn L.; Miller, Martin C.; Johnson, Gary E.; Williams, Greg D.; Southard, John A.; Buchanan, Rebecca A.

2006-02-01

Probability {approx} Location + Kinetic Energy Proxy + Tidal Height + Salmonid Density + Kinetic energy proxy ? Tidal Height + Tidal Height x Salmonid Density. (2) Stranding Probability {approx} Location + Total Wave Distance + Salmonid Density Index. (3) Log(Total Wave Height) {approx} Ship Block + Tidal Height + Location + Ship Speed. (4) Log(Total Wave Excursion Across the Beach) {approx} Location + Kinetic Energy Proxy + Tidal Height The above equations form the basis for a conceptual model of the factors leading to salmon stranding. The equations also form the basis for an approach for assessing impacts of dredging under the before/after study design.

Resistivity and Seismic Surface Wave Tomography Results for the Nevşehir Kale Region: Cappadocia, Turkey

Science.gov (United States)

Coşkun, Nart; Çakır, Özcan; Erduran, Murat; Arif Kutlu, Yusuf

2014-05-01

The Nevşehir Kale region located in the middle of Cappadocia with approximately cone shape is investigated for existence of an underground city using the geophysical methods of electrical resistivity and seismic surface wave tomography together. Underground cities are generally known to exist in Cappadocia. The current study has obtained important clues that there may be another one under the Nevşehir Kale region. Two-dimensional resistivity and seismic profiles approximately 4-km long surrounding the Nevşehir Kale are measured to determine the distribution of electrical resistivities and seismic velocities under the profiles. Several high resistivity anomalies with a depth range 8-20 m are discovered to associate with a systematic void structure beneath the region. Because of the high resolution resistivity measurement system currently employed we were able to isolate the void structure from the embedding structure. Low seismic velocity zones associated with the high resistivity depths are also discovered. Using three-dimensional visualization techniques we show the extension of the void structure under the measured profiles.

Nuclear ships and their safety

Energy Technology Data Exchange (ETDEWEB)

NONE

1961-04-15

Several aspects of nuclear ship propulsion, with special reference to nuclear safety, were discussed at an international symposium at Taormina, Italy, from 14-18 November 1960. Discussions on specific topics are conducted, grouped under the following headings: Economics and National Activities in Nuclear Ship Propulsion; International Problems and General Aspects of Safety for Nuclear Ships; Nuclear Ship Projects from the Angle of Safety; Ship Reactor Problems; Sea Motion and Hull Problems; Maintenance and Refuelling Problems; and Safety Aspects of Nuclear Ship Operation.

Approximate Method of Calculating Forces on Rudder During Ship Sailing on a Shipping Route

Directory of Open Access Journals (Sweden)

K. Zelazny

2014-09-01

Full Text Available Service speed of a ship in real weather conditions is a basic design parameter. Forecasting of this speed at preliminary design stage is made difficult by the lack of simple but at the same accurate models of forces acting upon a ship sailing on a preset shipping route. The article presents a model for calculating forces and moment on plane rudder, useful for forecasting of ship service speed at preliminary stages of ship design.

Breaking Ships in the World-System: An Analysis of Two Ship Breaking Capitals, Alang-Sosiya, India and Chittagong, Bangladesh

Directory of Open Access Journals (Sweden)

R. Scott Frey

2015-08-01

Full Text Available Centrality in the world-system allows countries to externalize their hazards or environmental harms on others. Core countries, for instance, dump heavy metals and greenhouse gases into the global sinks, and some of the core's hazardous products, production processes and wastes are displaced to the (semi peripheral zones of the world-system. Since few (semi peripheral countries have the ability to assess and manage the risks associated with such hazards, the transfer of core hazards to the (semi periphery has adverse environmental and socio-economic consequences for many of these countries and it has spawned conflict and resistance, as well as a variety of other responses. Most discussions of this risk globalization problem have failed to situate it firmly in the world-system frame emphasizing the process of ecological unequal exchange. Using secondary sources, I begin such a discussion by examining the specific problem of ship breaking (recycling core-based ocean going vessels for steel and other materials at the yards in Alang-Sosiya, India and Chittagong, Bangladesh. Attention centers on the nature and scope of ship breaking in these two locations, major drivers operating in the world-system, adverse consequences, the unequal mix of costs and benefits, and the failure of existing political responses at the domestic and international levels to reduce adequately the adverse consequences of ship breaking.

Nuclear ship accidents

International Nuclear Information System (INIS)

Oelgaard, P.L.

1993-05-01

In this report available information on 28 nuclear ship accident and incidents is considered. Of these 5 deals with U.S. ships and 23 with USSR ships. The ships are in almost all cases nuclear submarines. Only events that involve the nuclear propulsion plants, radiation exposures, fires/explosions and sea water leaks into the submarines are considered. Comments are made on each of the events, and at the end of the report an attempt is made to point out the weaknesses of the submarine designs which have resulted in the accidents. It is emphasized that much of the available information is of a rather dubious nature. consequently some of the assessments made may not be correct. (au)

Effects of an Anomalous Resistivity on the Power Deposition by Alfven Waves in Pre-Heated Spherical Tokamaks

Energy Technology Data Exchange (ETDEWEB)

Bruma, C.; Cuperman, S.; Komoshvili, K. [Tel Aviv Univ., Ramat Aviv (Israel)

2005-08-01

As it is the case with tokamaks in general, and moreover, due to their specific geometry (limited space for inboard solenoid magnets), low aspect ratio (spherical) tokamaks (STs) require additional auxiliary non-ohmic current startup and maintenance, generation of internal transport barriers (associated with underlying sheared poloidal flows and quasi-stationary radial electric fields), plasma heating, etc. One of the options to generate these necessary effects in STs is by the aid of rf waves launched from a suitable external antenna; in this option the effects just mentioned are a consequence of ponderomotive forces resulting from the interaction of the rf waves with the plasma. Since experimental data on STs (viz., the START-device) reveal the presence of an anomalous plasma resistivity (about four times Spitzer's one), we carried out a systematic parametric investigation of the effects of an increased plasma resistivity on the magnitude and spatial localization of the resulting power deposition.

Springing response due to bidirectional wave excitation

DEFF Research Database (Denmark)

Vidic-Perunovic, Jelena

2005-01-01

theories deal with the unidirectional wave excitation. This is quite standard. The problem is how to include more than one directional wave systems described by a wave spectrum with arbitrary heading. The main objective of the present work has been to account for the additional second-order springing......-linear (second order) high frequency springing analyses with unidirectional wave excitation are much more scattered. Some of the reasons are different level of wave excitation accounted in the different Executive Summary ivtheories, inclusion of additional hydrodynamic phenomena e.g. slamming in the time...... because, to the author's knowledge, this is the first time that the wave data were collected simultaneously with stress records on the deck of the ship. This is highly appreciated because one can use the precise input and not only the most probable sea state statistics. The actual picture of the sea waves...

Examples of, reasons for, and consequences of the poor quality of wind data from ships for the marine boundary layer - Implications for remote sensing

Science.gov (United States)

Pierson, Willard J., Jr.

1990-01-01

Wind reports by data buoys are used to demonstrate that these reports have in the past provided useful values for the synoptic scale winds and that at present these reports provide very reliable value for the synoptic scale winds. Past studies of wind reports by ships have revealed that the data are of poor quality, but the causes for this poor quality are not identified. Examples of the poor quality of wind data from ships are obtained by comparing ship reports with buoy reports and comparing reports of different kinds of ships with each other. These comparisons identify many different reasons for the poor quality of wind data from ships. Suggestions are made for improving the quality of ship data. The consequences of the poor quality of ship winds are described in terms of the effects on weather and wave forecasts. The implications for remotely sensed winds are discussed.

Estimates of fire environments in ship holds containing radioactive material packages

International Nuclear Information System (INIS)

Koski, J.A.; Cole, J.K.; Hohnstreiter, G.F.; Wix, S.D.

1995-01-01

Fire environments that occur on cargo ships differ significantly from the fire environments found in land transport. Cargo ships typically carry a large amount of flammable fuel for propulsion and shipboard power, and may transport large quantities of flammable cargo. As a result, sea mode transport accident records contain instances of long lasting and intense fires. Since Irradiated Nuclear Fuel (INF) casks are not carried on tankers with large flammable cargoes, most of these dramatic, long burning fires are not relevant threats, and transport studies must concentrate on those fires that are most likely to occur. By regulation, INF casks must be separated from flammable cargoes by a fire-resistant, liquid-tight partition. This makes a fire in an adjacent ship hold the most likely fire threat. The large size of a cargo ship relative to any spent nuclear fuel casks on board, however, may permit a severe, long lasting fire to occur with little or no thermal impact on the casks. Although some flammable materials such as shipping boxes or container floors may exist in the same hold with the cask, the amount of fuel available may not provide a significant threat to the massive transport casks used for radioactive materials. This shipboard fire situation differs significantly from the regulatory conditions specified in 10 CFR 71 for a fully engulfing pool fire. To learn more about the differences, a series of simple thermal analyses has been completed to estimate cask behavior in likely marine and land thermal accident situations. While the calculations are based on several conservative assumptions, and are only preliminary, they illustrate that casks are likely to heat much more slowly in shipboard hold fires than in an open pool fire. The calculations also reinforce the basic regulatory concept that for radioactive materials, the shipping cask, not the ship, is the primary protection barrier to consider

Dutch Ships and Sailors

NARCIS (Netherlands)

de Boer, Victor; Hoekstra, F.G.; Leinenga, Jurjen; van Rossum, Matthias

2014-01-01

Dutch Ships and Sailors provides an infrastructure for maritime historical datasets, linking correlating data through semantic web technology. It brings together datasets related to recruitment and shipping in the East-India trade (mainly 18th century) and in the shipping of the northern provinces

Reactors. Nuclear propulsion ships

International Nuclear Information System (INIS)

Fribourg, Ch.

2001-01-01

This article has for object the development of nuclear-powered ships and the conception of the nuclear-powered ship. The technology of the naval propulsion P.W.R. type reactor is described in the article B.N.3 141 'Nuclear Boilers ships'. (N.C.)

Ship Acquisition of Shipping Companies by Sale & Purchase Activities for Sustainable Growth: Exploratory Fuzzy-AHP Application

Directory of Open Access Journals (Sweden)

Keun-Sik Park

2018-05-01

Full Text Available Strengthening sale and purchase (S&P capacity has become a fundamental requirement for sustainable growth and corporate competitiveness in the modern shipping market. However, there is a lack of research related to S&P and its priority when shipping companies attempt to implement ship acquisition through S&P activities. To fill this gap, this paper conducts an empirical analysis to analyze priority factors during the acquisition of second-hand ships from the perspective of shipping companies. Business criteria are considered to be the most important factors in the analysis of the priority of ship acquisition and investment in shipping companies. To the best of our knowledge, this research is the first exploration covering Korean shipping companies’ ship acquisition through S&P activities. This study is expected to contribute to the better understanding of the role of S&P in ensuring the sustainability of shipping companies and to provide stakeholders with valuable insights.

Springing Response Due to Directional Wave Field Excitation

DEFF Research Database (Denmark)

Vidic-Perunovic, Jelena; Jensen, Jørgen Juncher

2004-01-01

This paper analyses the wave-induced high-frequency bending moment response of ships, denoted springing. The aim is to predict measured severe springing responses in a large bulk carrier. It is shown that the most important springing contribution is due to the resultant second order excitation...... in multidirectional sea. The incident pressure field from the second order bidirectional wave field is derived, including the non-linear cross-coupling terms between the two wave systems (e.g. wind driven waves and swell). The resulting effect of the super-harmonic cross-coupling interaction terms on the springing...... response is discussed. An example with opposing waves is given, representing probably the 'worst' case for energy exchange between the wave systems. Theoretical predictions of standard deviation of wave- and springing-induced stress amidships are compared with full-scale measurements for a bulk carrier....

Quantifying the Role of Atmospheric Forcing in Ice Edge Retreat and Advance Including Wind-Wave Coupling

Science.gov (United States)

2015-09-30

Low-Level Profiles, Pressure, Temperature, Humidity Rawinsonde (Kite, Tethered Balloon , Unmanned Aerial vehicle) Wave Characteristics, Wind wave and...Thermistor, Ship intake, Manual Bucket Tropospheric Profiles, 4/day – Pressure, Temperature, Humidity, Wind Vector Rawinsonde (Weather Balloon

Slamming Simulations in a Conditional Wave

DEFF Research Database (Denmark)

Seng, Sopheak; Jensen, Jørgen Juncher

2012-01-01

A study of slamming events in conditional waves is presented in this paper. The ship is sailing in head sea and the motion is solved for under the assumption of rigid body motion constrained to two degree-of-freedom i.e. heave and pitch. Based on a time domain non-linear strip theory most probable...

Outer Dynamics of Ship Collisions

DEFF Research Database (Denmark)

Pedersen, Preben Terndrup

1996-01-01

The purpose is to present analysis procedures for the motion of ships during ship-ship collisions and for ship collisions with offshore structures. The aim is to estimate that part of the lost kinetic energy which will have to be absorbed by rupture and plastic damage of the colliding structures....

Reliability analysis of production ships with emphasis on load combination and ultimate strength

Energy Technology Data Exchange (ETDEWEB)

Wang, Xiaozhi

1995-05-01

This thesis deals with ultimate strength and reliability analysis of offshore production ships, accounting for stochastic load combinations, using a typical North Sea production ship for reference. A review of methods for structural reliability analysis is presented. Probabilistic methods are established for the still water and vertical wave bending moments. Linear stress analysis of a midships transverse frame is carried out, four different finite element models are assessed. Upon verification of the general finite element code ABAQUS with a typical ship transverse girder example, for which test results are available, ultimate strength analysis of the reference transverse frame is made to obtain the ultimate load factors associated with the specified pressure loads in Det norske Veritas Classification rules for ships and rules for production vessels. Reliability analysis is performed to develop appropriate design criteria for the transverse structure. It is found that the transverse frame failure mode does not seem to contribute to the system collapse. Ultimate strength analysis of the longitudinally stiffened panels is performed, accounting for the combined biaxial and lateral loading. Reliability based design of the longitudinally stiffened bottom and deck panels is accomplished regarding the collapse mode under combined biaxial and lateral loads. 107 refs., 76 refs., 37 tabs.

Handbook of nuclear ships

International Nuclear Information System (INIS)

1981-03-01

First, the government organs and other organizations related to nuclear ships and their tasks are described. The fundamental plan for the development of nuclear ships had been determined in July, 1963, and was revised three times thereafter. However in December, 1980, new determination to carry out the research works also was made. The course of the construction of the nuclear ship ''Mutsu'' from 1955 to 1980, the main particulars of the nuclear ship ''Mutsu'' and the drawing of the general arrangement are shown. The designated port for berthing the Mutsu was completed in 1972 in Ominato, Aomori Prefecture, but after the happening of radiation leak during the trial operation of the Mutsu in 1974, it was agreed to remove the port. The main works to be carried out at the port and the port facilities are explained. The progress of the examination of safety of the Mutsu and the result, the test of raising the power output carried out in 1974, and the course of selecting the port for making the repair works of the Mutsu are described. The law concerning Japan Nuclear Ship Research and Development Agency had been instituted in 1963, and was revised four times thereafter. The change of the budget for the tests and researches related to nuclear ships in Japan is shown. The state of development of nuclear ships in foreign countries, the international organs related to atomic energy, shipping, shipbuilding and energy, and chronological table are introduced. (Kako, I.)

Outer Dynamics of Ship Collisions

DEFF Research Database (Denmark)

Pedersen, Preben Terndrup

1996-01-01

The purpose of these notes is to present analysis procedures for the motion of ships during ship-ship collisions and for ship collisons with offshore structures. The aim is to estimate that part of the lost kinetic energy which will have to be absorbed by rupture and plastic damage of the colliding...

On Impact Mechanics in Ship Collisions

DEFF Research Database (Denmark)

Pedersen, Preben Terndrup; Zhang, Shengming

1998-01-01

The purpose of this paper is to present analytical, closed-form expressions for the energy released for crushing and the impact impulse during ship collisions. Ship-ship collisions, ship collisions with rigid walls and ship collisions with flexible offshore structures are considered. The derived ...

Towards a nuclear merchant ship

International Nuclear Information System (INIS)

Nicholson, R.L.R.; Llewelyn, G.I.W.; Farmer, A.A.

1976-01-01

The operation of nuclear merchant ships is likely to be attended by a number of constraints and requirements. Not all of these can be fully resolved until such ships come into use and the necessary experience and confidence have been acquired. But the timing of commercial introduction, if it comes about, will depend on the relative economics of nuclear versus fossil fuel propulsion, and the differences in turn depend in part on the operating costs particular to nuclear ships. A review of operation aspects is essential not only to commercial appraisal; each country whose trade may be carried in nuclear ships - whether it will build such ships or not - will have occasion to give some attention to the problems. It is an international problem and is, as noted later, being considered internationally. This paper; i) reviews some of the operational aspects as seen in the U.K.; ii) summarizes views received by the Nuclear Merchant Ship Unit (NMSU) from U.K. shipping, shipbuilding and nuclear industries on the prospects of a U.K. nuclear merchant ship. (author)

An Arctic Ice/Ocean Coupled Model with Wave Interactions

Science.gov (United States)

2015-09-30

discussed by DRI participants may aid our understanding as well, e.g. those conducted in the Hamburg Ship Model Basin. Our theoretical advances benefit...the project are – continued modifications to the Arctic wide WIM code in association with advances relating to a new ice/ocean model known as... Auckland , December 2014. Montiel, F. Transmission of ocean waves through a row of randomly perturbed circular ice floes. Minisymposium on Wave Motions of

Ship Power System Analysis Based on Safety Aspects

Directory of Open Access Journals (Sweden)

Urbaha Margarita

2017-08-01

Full Text Available This article analyses the reasons for the reduction of insulating resistance, processes influencing them and isolation diagnostic methods. It provides a short description of electrical safety situation on ships with isolated neutral electrical power systems. It also covers the methods of protecting personnel from electric shock or preventing ignition or arching damage at the fault location with the help of fault current compensation. Principal fault current compensation circuit diagrams are analysed by using the minimum value and time of transient fault current as criteria.

Shipping Information Pipeline

DEFF Research Database (Denmark)

Jensen, Thomas; Vatrapu, Ravi

2015-01-01

and national borders within international shipping which is a rather complex domain. The intellectual objective is to generate and evaluate the efficacy and effectiveness of design principles for inter-organizational information infrastructures in the international shipping domain that can have positive...

Navy Hospital ships in history

Directory of Open Access Journals (Sweden)

Sougat Ray

2017-01-01

Full Text Available Hospital ships are operated by the Naval forces in or near war zones to provide medical assistance to the wounded personnel of all nationalities and not be used for any military purpose. Hospital ships possibly existed in ancient times and the Athenian Navy had a ship named Therapia. However, it was only during the 17th century that it became a common practice for the naval squadrons to be accompanied by large ships with the facilities of carrying the wounded after each engagement. In 1860, the steamships HMS Melbourne and HMS Mauritius were equipped with genuine medical facilities. They were manned by the Medical Staff Corps and provided services to the British expedition to China. During the World War I and World War II, passenger ships were converted for use as hospital ships and were started to be used on a massive scale. RMS Aquitania and HMHS Britannic were two famous examples of hospital ships used extensively. Modern US hospital ships USNS Mercy and USNS Comfort are operated by Military Sealift Command of the US Navy. Their primary mission is to provide emergency on-site care for US combatant forces deployed in war or other operations.

Effects of ship casualties on reactor safety and marine reactor design

International Nuclear Information System (INIS)

Agena, H.H.

1978-01-01

Ship casualties such as collision, grounding, fire and explosions, leakage and partial flooding may severely impair the safety of the nuclear reactor plant and result in nuclear hazards to the crew and the environment. Engineered safeguards are being discussed for protection against such consequences: manoeuvrability, structural (passive) collision and fire protection, protection against external fires and pressure waves, after heat transmission in case of a casualty, and after heat transmission out off the sunk wreck. Existing requirements will be discussed, shortly

Civilian nuclear ships

International Nuclear Information System (INIS)

Oelgaard, P.L.

1993-03-01

This report contains a review of the information available on nuclear powered ships, built for civilian purposes. In the introduction a short discussion is given of the reasons for the limited use of nuclear ships for these purposes. In the second section a brief review is presented of data for the three experimental/merchant ships build by the United States, Germany and Japan, i.e. NS Savannah, NS Otto Hahn and NS Mutsu. In the third section the Soviet/Russian icebreaker NS Lenin is considered. Its design, operational experience and the introduction of a new nuclear propulsion plant is reviewed. In the fourth section the newer Soviet/Russian icebreakers with nuclear propulsion are considered. Finally design of the Soviet/Russian icebreaker transport/container ship NS Sevmorput is reviewed in the fifth section. The future Russian plans for nuclear vessels for the arctic waters are briefly discussed. (au)

Superheavy element research at the velocity filter ship

International Nuclear Information System (INIS)

Heinz, S.

2012-01-01

The Separator for Heavy Ion Reaction Products (SHIP) is a velocity filter located at the UNILAC accelerator of GSI Darmstadt, Germany. For about 35 years a broad experimental program in the field of superheavy element research is running at SHIP. During the last years particularly investigations in the region of the heaviest known nuclei were performed. In fusion reactions of 48 Ca + 248 Cm → 296 116* a total of six decay chains was observed which could be attributed to the evaporation residues 292 116 and 293 116. In this experiment, data measured previously on the same isotopes in Dubna were well confirmed. Besides, two attempts were made to synthesize isotopes of the still unobserved element Z = 120 in reactions of 64 Ni + 238 U and 54 Cr + 248 Cm. No events were observed in these experiments leading to one-event cross-section limits of 90 fb and 560 fb, respectively. For future superheavy element research, a new superconducting continuous wave LINAC is planned at GSI which shall deliver beam intensities of up to 1014 particles per second. In this context we are developing a next generation separator and new detection techniques

Distribution of deep water wave power around the Indian coast based on ship observations

Digital Repository Service at National Institute of Oceanography (India)

Chandramohan, P.; Nayak, B.U.; RamaRaju, V.S.

distribution of wave power in different directions over a year for each grid is presented. The annual mean wave power along the Indian coast varies from 11.4 to 15.2 KW per metre length of wave crest with a maximum of 15.2 KW for the regions off south Kerala...

Regional Sediment Management Studies of Matagorda Ship Channel and Matagorda Bay System, Texas

Science.gov (United States)

2013-08-01

undisturbed free water surface.” The USACE presently has no standardized method to measure the fluid mud to determine nautical depth. The Engineer Manual...structural member in the bottom of the hull and channel bottom) is used to account for parameters such as ship motion from waves, squat , safety...distance between the nautical bottom and undisturbed free water surface. To complete the definition of nautical bottom, the physical characteristic(s) on

International Standardization in the Design of "Shore to Ship" - Power Supply Systems of Ships in Port

Science.gov (United States)

Tarnapowicz, Dariusz; German-Galkin, Sergiej

2018-03-01

The decisive source of air pollution emissions in ports is the berthed ships. This is primarily caused by the work of ship's autonomous generator sets. One way of reducing the air pollution emissions in ports is the supply of ships from electricity inland system. The main problem connected with the power connection of ships to the inland network is caused by different values of levels and frequencies of voltages in these networks (in various countries) in relation to different values of levels and frequencies of voltages present in the ship's network. It is also important that the source power can range from a few hundred kW up to several MW. In order to realize a universal „Shore to Ship" system that allows the connection of ships to the electricity inland network, the international standardization is necessary. This article presents the current recommendations, standards and regulations for the design of „Shore to Ship" systems.

Ships on hero stones from the west coast of India

Digital Repository Service at National Institute of Oceanography (India)

Tripati, S.

tossed their cargo in the waves of the sea in times of danger and promised their Gods to make a donation if ever He brought them safely out of this peril. The Buddhist goddess ?Tara? is the protectress and a number of ?Tara? images have been found... of Naval Warfare in India Boats were not only engaged for transportation of cargo, crossing rivers and lakes pleasure trips for noble people but also for naval warfare. This practice also appears to be very old. The art of employing boats and ships...

Thermo-hydraulic characteristics of ship propulsion reactor in the conditions of ship motions and safety assessment

International Nuclear Information System (INIS)

Kobayashi, Michiyuki; Murata, Hiroyuki; Sawada, Kenichi; Inasaka, Fujio; Aya, Izuo; Shiozaki, Koki

1999-01-01

By inputting the experimental data, information and others on thermo-hydraulic characteristics of integrated ship propulsion reactor accumulated hitherto by the Ship Research Institute and some recent cooperation results into the nuclear ship engineering simulation system, it was conducted not only to contribute an improvement study on next ship reactor by executing general analysis and evaluation on motion characteristics under ship body motion conditions, safety at accidents, and others of the integrated ship reactor but also to investigate and prepare some measures to apply fundamental experiment results based on obtained here information to safety countermeasure of the nuclear ships. In 1997 fiscal year, on safety of the integrated ship propulsion reactor loading nuclear ship, by adding experimental data on unstable flow analysis and information on all around of the analysis to general data base fundamental program, development to intellectual data base program was intended; on effect of pulsation flow on thermo-hydraulic characteristics of ship propulsion reactor; after pulsation flow visualization experiment, experimental equipment was reconstructed into heat transfer type to conduct numerical analysis of pulsation flow by confirming validity of numerical analysis code under comparison with the visualization experiment results; and on thermo-hydraulic behavior in storage container at accident of active safety type ship propulsion reactor; a flashing vibration test using new apparatus finished on its higher pressurization at last fiscal year to examine effects of each parameter such as radius and length of exhausting nozzle and pool water temperature. (G.K.)

Knowledge-based full-automatic control system for a nuclear ship reactor

International Nuclear Information System (INIS)

Shimazaki, J.; Nakazawa, T.; Yabuuchi, N.

2000-01-01

Plant operations aboard nuclear ships require quick judgements and actions due to changing marine conditions such as wind, waves and currents. Furthermore, additional human support is not available for nuclear ship operation at sea, so advanced automatic operations are necessary to reduce the number of operators required finally. Therefore, an advanced automatic operating system has been developed based on operational knowledge of nuclear ship 'Mutsu' plant. The advanced automatic operating system includes both the automatic operation system and the operator-support system which assists operators in completing actions during plant accidents, anomaly diagnosis and plant supervision. These system are largely being developed using artificial intelligent techniques such as neural network, fuzzy logic and knowledge-based expert. The automatic operation system is fundamentally based upon application of an operator's knowledge of both normal (start-up to rated power level) and abnormal (after scram) operations. Comparing plant behaviors from start-up to power level by the automatic operation with by 'Mutsu' manual operation, stable automatic operation was obtained almost same as manual operation within all operating limits. The abnormal automatic system was for hard work of manual operations after scram or LOCA accidents. An integrating system with the normal and the abnormal automatic systems are being developed for interacting smoothly both systems. (author)

Isolation of a conjugative F-like plasmid from a multidrug-resistant Escherichia coli strain CM6 using tandem shock wave-mediated transformation.

Science.gov (United States)

Soto-Alonso, G; Cruz-Medina, J A; Caballero-Pérez, J; Arvizu-Hernández, I; Ávalos-Esparza, L M; Cruz-Hernández, A; Romero-Gómez, S; Rodríguez, A L; Pastrana-Martínez, X; Fernández, F; Loske, A M; Campos-Guillén, J

2015-07-01

Genetic characterization of plasmids from bacterial strains provides insight about multidrug resistance. Ten wild type Escherichia coli (E. coli) strains isolated from cow fecal samples were characterized by their antibiotic resistance profile, plasmid patterns and three different identification methods. From one of the strains, a fertility factor-like plasmid was replicated using tandem shock wave-mediated transformation. Underwater shock waves with a positive pressure peak of up to approximately 40 MPa, followed by a pressure trough of approximately -19 MPa were generated using an experimental piezoelectric shock wave source. Three different shock wave energies and a fixed delay of 750 μs were used to study the relationship between energy and transformation efficiency (TE), as well as the influence of shock wave energy on the integrity of the plasmid. Our results showed that the mean shock wave-mediated TE and the integrity of the large plasmid (~70 kb) were reduced significantly at the energy levels tested. The sequencing analysis of the plasmid revealed a high identity to the pHK17a plasmid, including the replication system, which was similar to the plasmid incompatibility group FII. It also showed that it carried an extended spectrum beta-lactamase gene, ctx-m-14. Furthermore, diverse genes for the conjugative mechanism were identified. Our results may be helpful in improving methodologies for conjugative plasmid transfer and directly selecting the most interesting plasmids from environmental samples. Copyright © 2015 Elsevier B.V. All rights reserved.

Spontaneous emergence of rogue waves in partially coherent waves: A quantitative experimental comparison between hydrodynamics and optics.

Science.gov (United States)

El Koussaifi, R; Tikan, A; Toffoli, A; Randoux, S; Suret, P; Onorato, M

2018-01-01

Rogue waves are extreme and rare fluctuations of the wave field that have been discussed in many physical systems. Their presence substantially influences the statistical properties of a partially coherent wave field, i.e., a wave field characterized by a finite band spectrum with random Fourier phases. Their understanding is fundamental for the design of ships and offshore platforms. In many meteorological conditions waves in the ocean are characterized by the so-called Joint North Sea Wave Project (JONSWAP) spectrum. Here we compare two unique experimental results: the first one has been performed in a 270 m wave tank and the other in optical fibers. In both cases, waves characterized by a JONSWAP spectrum and random Fourier phases have been launched at the input of the experimental device. The quantitative comparison, based on an appropriate scaling of the two experiments, shows a very good agreement between the statistics in hydrodynamics and optics. Spontaneous emergence of heavy tails in the probability density function of the wave amplitude is observed in both systems. The results demonstrate the universal features of rogue waves and provide a fundamental and explicit bridge between two important fields of research. Numerical simulations are also compared with experimental results.

Spontaneous emergence of rogue waves in partially coherent waves: A quantitative experimental comparison between hydrodynamics and optics

Science.gov (United States)

El Koussaifi, R.; Tikan, A.; Toffoli, A.; Randoux, S.; Suret, P.; Onorato, M.

2018-01-01

Rogue waves are extreme and rare fluctuations of the wave field that have been discussed in many physical systems. Their presence substantially influences the statistical properties of a partially coherent wave field, i.e., a wave field characterized by a finite band spectrum with random Fourier phases. Their understanding is fundamental for the design of ships and offshore platforms. In many meteorological conditions waves in the ocean are characterized by the so-called Joint North Sea Wave Project (JONSWAP) spectrum. Here we compare two unique experimental results: the first one has been performed in a 270 m wave tank and the other in optical fibers. In both cases, waves characterized by a JONSWAP spectrum and random Fourier phases have been launched at the input of the experimental device. The quantitative comparison, based on an appropriate scaling of the two experiments, shows a very good agreement between the statistics in hydrodynamics and optics. Spontaneous emergence of heavy tails in the probability density function of the wave amplitude is observed in both systems. The results demonstrate the universal features of rogue waves and provide a fundamental and explicit bridge between two important fields of research. Numerical simulations are also compared with experimental results.

The Human Element and Autonomous Ships

Directory of Open Access Journals (Sweden)

Sauli Ahvenjärvi

2016-09-01

Full Text Available The autonomous ship technology has become a “hot” topic in the discussion about more efficient, environmentally friendly and safer sea transportation solutions. The time is becoming mature for the introduction of commercially sensible solutions for unmanned and fully autonomous cargo and passenger ships. Safety will be the most interesting and important aspect in this development. The utilization of the autonomous ship technology will have many effects on the safety, both positive and negative. It has been announced that the goal is to make the safety of an unmanned ship better that the safety of a manned ship. However, it must be understood that the human element will still be present when fully unmanned ships are being used. The shore-based control of a ship contains new safety aspects and an interesting question will be the interaction of manned and unmanned ships in the same traffic area. The autonomous ship technology should therefore be taken into account on the training of seafarers. Also it should not be forgotten that every single control algorithm and rule of the internal decision making logic of the autonomously navigating ship has been designed and coded by a human software engineer. Thus the human element is present also in this point of the lifetime navigation system of the autonomous ship.

Applied Wave Mathematics Selected Topics in Solids, Fluids, and Mathematical Methods

CERN Document Server

Quak, Ewald

2009-01-01

This edited volume addresses the importance of mathematics in wave-related research, and its tutorial style contributions provide educational material for courses or seminars. It presents highlights from research carried out at the Centre for Nonlinear Studies in Tallinn, Estonia, the Centre of Mathematics for Applications in Oslo, Norway, and by visitors from the EU project CENS-CMA. The example applications discussed include wave propagation in inhomogeneous solids, liquid crystals in mesoscopic physics, and long ship waves in shallow water bodies. Other contributions focus on specific mathe

On impact mechanics in ship collisions

DEFF Research Database (Denmark)

Pedersen, Preben Terndrup; Zhang, Shengming

1998-01-01

The purpose of this paper is to present analytical, closed-form expressions for the energy released for crushing and the impact impulse during ship collisions. Ship–ship collisions, ship collisions with rigid walls and ship collisions with flexible offshore structures are considered. The derived ...

Seasonal Climate Associated with Major Shipping Routes in the North Pacific and North Atlantic

Directory of Open Access Journals (Sweden)

Jau-Ming Chen

2014-01-01

Full Text Available The major shipping routes in the North Pacific (NP and North Atlantic (NA are analyzed via ship-reported records compiled by the International Comprehensive Ocean-Atmosphere Data Set (ICOADS. The shipping route seasonal characteristics and associated climatic features are also examined. In the NP, the dominant cross-basin route takes a great-circle path between East Asia and North America along 54°N north of the Aleutian Islands throughout the year. This route penetrates the Aleutian low center where ocean waves and winds are relatively weaker than those in the low¡¦s southern section south of 50°N. Moreover, the Earth¡¦s spherical shape makes a higher-latitude route shorter in navigational distance across the NP than a lower-latitude route. Two additional mid-latitude routes through the 40° - 50°N region appear in summer when the Aleutian low vanishes. In the NA, the major shipping routes form an X-shaped pattern in the oceans south of 40°N to connect North America/the Panama Canal and the Mediterranean Sea/the British Isles and Europe. These major shipping routes are far from the influence of the Icelandic low and thus are used throughout the year due to the stability in marine conditions and their general efficiency. A third and more zonal route appears to the north of the X-shaped routes in the 40° - 50°N region. Weak influence from the Icelandic low on marine conditions during summer and spring means that more ships take this route in summer and spring than in winter and fall.

Bow hull-form optimization in waves of a 66,000 DWT bulk carrier

Directory of Open Access Journals (Sweden)

Jin-Won Yu

2017-09-01

Full Text Available This paper uses optimization techniques to obtain bow hull form of a 66,000 DWT bulk carrier in calm water and in waves. Parametric modification functions of SAC and section shape of DLWL are used for hull form variation. Multi-objective functions are applied to minimize the wave-making resistance in calm water and added resistance in regular head wave of λ/L = 0.5. WAVIS version 1.3 is used to obtain wave-making resistance. The modified Fujii and Takahashi's formula is applied to obtain the added resistance in short wave. The PSO algorithm is employed for the optimization technique. The resistance and motion characteristics in calm water and regular and irregular head waves of the three hull forms are compared. It has been shown that the optimal brings 13.2% reduction in the wave-making resistance and 13.8% reduction in the added resistance at λ/L = 0.5; and the mean added resistance reduces by 9.5% at sea state 5.

Influence of standing-wave electric field pattern on the laser damage resistance of HfO sub 2 thin films

CERN Document Server

Protopapa, M L; De Tomasi, F; Di Giulio, M; Perrone, M R; Scaglione, S

2002-01-01

The standing-wave electric field pattern that forms inside an optical coating as a consequence of laser irradiation is one of the factors influencing the coating laser-induced damage threshold. The influence of the standing-wave electric field profile on the damage resistance to ultraviolet radiation of hafnium dioxide (HfO sub 2) thin films was investigated in this work. To this end, HfO sub 2 thin films of different thicknesses deposited by the electron beam evaporation technique at the same deposition conditions were analyzed. Laser damage thresholds of the samples were measured at 308 nm (XeCl laser) by the photoacoustic beam deflection technique and microscopic inspections. The dependence of the laser damage threshold on the standing-wave electric field pattern was analyzed.

Advanced Demonstration of Motion Correction for Ship-to-Ship Passive Inspections

Energy Technology Data Exchange (ETDEWEB)

Ziock, Klaus-Peter [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Boehnen, Chris Bensing [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Ernst, Joseph [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

2013-09-30

Passive radiation detection is a key tool for detecting illicit nuclear materials. In maritime applications it is most effective against small vessels where attenuation is of less concern. Passive imaging provides: discrimination between localized (threat) and distributed (non-threat) sources, removal of background fluctuations due to nearby shorelines and structures, source localization to an individual craft in crowded waters, and background subtracted spectra. Unfortunately, imaging methods cannot be easily applied in ship-to-ship inspections because relative motion of the vessels blurs the results over many pixels, significantly reducing sensitivity. This is particularly true for the smaller water craft where passive inspections are most valuable. In this project we performed tests and improved the performance of an instrument (developed earlier under, “Motion Correction for Ship-to-Ship Passive Inspections”) that uses automated tracking of a target vessel in visible-light images to generate a 3D radiation map of the target vessel from data obtained using a gamma-ray imager.

Marine traffic model based on cellular automaton: Considering the change of the ship's velocity under the influence of the weather and sea

Science.gov (United States)

Qi, Le; Zheng, Zhongyi; Gang, Longhui

2017-10-01

It was found that the ships' velocity change, which is impacted by the weather and sea, e.g., wind, sea wave, sea current, tide, etc., is significant and must be considered in the marine traffic model. Therefore, a new marine traffic model based on cellular automaton (CA) was proposed in this paper. The characteristics of the ship's velocity change are taken into account in the model. First, the acceleration of a ship was divided into two components: regular component and random component. Second, the mathematical functions and statistical distribution parameters of the two components were confirmed by spectral analysis, curve fitting and auto-correlation analysis methods. Third, by combining the two components, the acceleration was regenerated in the update rules for ships' movement. To test the performance of the model, the ship traffic flows in the Dover Strait, the Changshan Channel and the Qiongzhou Strait were studied and simulated. The results show that the characteristics of ships' velocities in the simulations are consistent with the measured data by Automatic Identification System (AIS). Although the characteristics of the traffic flow in different areas are different, the velocities of ships can be simulated correctly. It proves that the velocities of ships under the influence of weather and sea can be simulated successfully using the proposed model.

An assessment of simplified methods to determine damage from ship-to-ship collisions

International Nuclear Information System (INIS)

Parks, M.B.; Ammerman, D.J.

1996-01-01

Sandia National Laboratories (SNL) is studying the safety of shipping, radioactive materials (RAM) by sea, the SeaRAM project (McConnell, et al. 1995), which is sponsored by the US Department of Energy (DOE). The project is concerned with the potential effects of ship collisions and fires on onboard RAM packages. Existing methodologies are being assessed to determine their adequacy to predict the effect of ship collisions and fires on RAM packages and to estimate whether or not a given accident might lead to a release of radioactivity. The eventual goal is to develop a set of validated methods, which have been checked by comparison with test data and/or detailed finite element analyses, for predicting the consequences of ship collisions and fires. These methods could then be used to provide input for overall risk assessments of RAM sea transport. The emphasis of this paper is on methods for predicting- effects of ship collisions

Rogue waves in the ocean - review and progress

Science.gov (United States)

Pelinovsky, Efim; Kharif, Christian; Slunyaev, Alexey

2010-05-01

Rogue waves in the ocean and physical mechanisms of their appearance are discussed. Theyse waves are among waves naturally observed by people on the sea surface that represent inseparable feature of the Ocean. Rogue waves appear from nowhere, cause danger and disappear at once. They may occur at the surface of a relatively calm sea, reach not very high amplitudes, but be fatal for ships and crew due to their unexpectedness and abnormal features. The billows appear suddenly exceeding the surrounding waves twice and more, and obtained many names: abnormal, exceptional, extreme, giant, huge, sudden, episodic, freak, monster, rogue, vicious, killer, mad- or rabid-dog waves; cape rollers, holes in the sea, walls of water, three sisters… Freak monsters, though living for seconds, were able to arouse superstitious fear of the crew, cause damage, death of heedless sailors or the whole ship. All these epithets are full of human fear and feebleness. The serious studies of the phenomenon started about 20-30 years ago and have been intensified during the recent decade. The research is being conducted in different fields: in physics (search of physical mechanisms and adequate models of wave enhancement and statistics), in geoscience (determining the regions and weather conditions when rogue waves are most probable), and in ocean and coastal engineering (estimations of the wave loads on fixed and drifting floating structures). Thus, scientists and engineers specializing in different subject areas are involved in the solution of the problem. The state-of-art of the rogue wave study is summarized in our book [Kharif, Ch., Pelinovsky, E., and Slunyaev, A. Rogue Waves in the Ocean. Springer, 2009] and presented in given review. Firstly, we start with a brief introduction to the problem of freak waves aiming at formulating what is understood as rogue or freak waves, what consequences their existence imply in our life, why people are so worried about them. Then we discuss existing

High cost for drilling ships

International Nuclear Information System (INIS)

Hooghiemstra, J.

2007-01-01

Prices for the rent of a drilling ship are very high. Per day the rent is 1% of the price for building such a ship, and those prices have risen as well. Still, it is attractive for oil companies to rent a drilling ship [nl

Accidents in nuclear ships

Energy Technology Data Exchange (ETDEWEB)

Oelgaard, P L [Risoe National Lab., Roskilde (Denmark); [Technical Univ. of Denmark, Lyngby (Denmark)

1996-12-01

This report starts with a discussion of the types of nuclear vessels accidents, in particular accidents which involve the nuclear propulsion systems. Next available information on 61 reported nuclear ship events in considered. Of these 6 deals with U.S. ships, 54 with USSR ships and 1 with a French ship. The ships are in almost all cases nuclear submarines. Only events that involve the sinking of vessels, the nuclear propulsion plants, radiation exposures, fires/explosions, sea-water leaks into the submarines and sinking of vessels are considered. For each event a summary of available information is presented, and comments are added. In some cases the available information is not credible, and these events are neglected. This reduces the number of events to 5 U.S. events, 35 USSR/Russian events and 1 French event. A comparison is made between the reported Soviet accidents and information available on dumped and damaged Soviet naval reactors. It seems possible to obtain good correlation between the two types of events. An analysis is made of the accident and estimates are made of the accident probabilities which are found to be of the order of 10{sup -3} per ship reactor years. It if finally pointed out that the consequences of nuclear ship accidents are fairly local and does in no way not approach the magnitude of the Chernobyl accident. It is emphasized that some of the information on which this report is based, may not be correct. Consequently some of the results of the assessments made may not be correct. (au).

Accidents in nuclear ships

International Nuclear Information System (INIS)

Oelgaard, P.L.

1996-12-01

This report starts with a discussion of the types of nuclear vessels accidents, in particular accidents which involve the nuclear propulsion systems. Next available information on 61 reported nuclear ship events in considered. Of these 6 deals with U.S. ships, 54 with USSR ships and 1 with a French ship. The ships are in almost all cases nuclear submarines. Only events that involve the sinking of vessels, the nuclear propulsion plants, radiation exposures, fires/explosions, sea-water leaks into the submarines and sinking of vessels are considered. For each event a summary of available information is presented, and comments are added. In some cases the available information is not credible, and these events are neglected. This reduces the number of events to 5 U.S. events, 35 USSR/Russian events and 1 French event. A comparison is made between the reported Soviet accidents and information available on dumped and damaged Soviet naval reactors. It seems possible to obtain good correlation between the two types of events. An analysis is made of the accident and estimates are made of the accident probabilities which are found to be of the order of 10 -3 per ship reactor years. It if finally pointed out that the consequences of nuclear ship accidents are fairly local and does in no way not approach the magnitude of the Chernobyl accident. It is emphasized that some of the information on which this report is based, may not be correct. Consequently some of the results of the assessments made may not be correct. (au)

Trends of shipping markets development

Directory of Open Access Journals (Sweden)

Tomasz Nowosielski

2012-06-01

Full Text Available Shipping markets are dependent on international trade transactions that generate transport needs. These needs can dynamically change depending on global natural resources and commodity markets situation. The changes affecting shipping markets can also be caused by changes to the existing cargo flows and by establishing new ones in different geographies. It is anticipated that in the future shipping markets will change, visible by a decline in shipping in North America and Europe and an increase in Asia.

Advanced ship systems condition monitoring for enhanced inspection, maintenance and decision making in ship operations

OpenAIRE

Lazakis, Iraklis; Dikis, Konstantinos; Michala, Anna Lito; Theotokatos, Gerasimos

2016-01-01

Structural and machinery failures in the day-to-day ship operations may lead to major accidents, endangering crew and\\ud passengers onboard, posing a threat to the environment, damaging the ship itself and having a great impact in terms of business\\ud losses. In this respect, this paper presents the INCASS (Inspection Capabilities for Enhanced Ship Safety) project which aims\\ud bringing an innovative solution to the ship inspection regime through the introduction of enhanced inspection of shi...

Standing steady-state wave-making calculation method for air cushion vehicles; Air cushion vehicle no teijo zoha keisanho ni tsuite

Energy Technology Data Exchange (ETDEWEB)

Eguchi, T [Mitsui Engineering and Shipbuilding Co. Ltd., Tokyo (Japan)

1996-04-10

The pulse-height distribution of a cushion room of air cushion vehicle (ACV) has been tried to be approached by means of the panel shift type Rankine source method. When using this method, it was not required to introduce the pressure distribution model simulating the fall-off effect for the step-formed cushion pressure distribution. The wave form and wave making resistance could be estimated precisely by assigning the pressure gradient to one longitudinal direction panel in the calculation. The waveform shape within the cushion room could be calculated rather precisely by comparing with the analytic solution. This calculation method did have an ability providing the pulse-height information in the cushion room of ACV for seal design and configuration of ships. The analytic solution using for the comparison was sufficient for determining the pulse-height in the high speed region. However, it was hard to respond to non-linear problems or optional shape problems. It was pointed out to be further improved. 5 refs., 8 figs.

Guide to ship sanitation

National Research Council Canada - National Science Library

2011-01-01

"The third edition of the Guide to Ship Sanitation presents the public health significance of ships in terms of disease and highlights the importance of applying appropriate control measures"--Back cover...

Estimation of sea surface wave height from Bhaskara II SAMIR data

Digital Repository Service at National Institute of Oceanography (India)

Rao, M.V.; Viswambharan, N.K.; Rao, L.V.G.

from R V Gaveshani and visual observations from other ships as reported in IDWR) are available. Using this, an attempt has been made to obtain an empirical relation between brightness temperature and significant wave height. Linear correlation between...

Producing acoustic 'Frozen Waves': simulated experiments with diffraction/attenuation resistant beams in lossy media.

Science.gov (United States)

Prego-Borges, José L; Zamboni-Rached, Michel; Recami, Erasmo; Costa, Eduardo Tavares

2014-08-01

The so-called Localized Waves (LW), and the "Frozen Waves" (FW), have raised significant attention in the areas of Optics and Ultrasound, because of their surprising energy localization properties. The LWs resist the effects of diffraction for large distances, and possess an interesting self-reconstruction -self-healing- property (after obstacles with size smaller than the antenna's); while the FWs, a sub-class of LWs, offer the possibility of arbitrarily modeling the longitudinal field intensity pattern inside a prefixed interval, for instance 0⩽z⩽L, of the wave propagation axis. More specifically, the FWs are localized fields "at rest", that is, with a static envelope (within which only the carrier wave propagates), and can be endowed moreover with a high transverse localization. In this paper we investigate, by simulated experiments, various cases of generation of ultrasonic FW fields, with the frequency of f0=1 MHz in a water-like medium, taking account of the effects of attenuation. We present results of FWs for distances up to L=80 mm, in attenuating media with absorption coefficient α in the range 70⩽α⩽170 dB/m. Such simulated FW fields are constructed by using a procedure developed by us, via appropriate finite superpositions of monochromatic ultrasonic Bessel beams. We pay due attention to the selection of the FW parameters, constrained by the rather tight restrictions imposed by experimental Acoustics, as well as to some practical implications of the transducer design. The energy localization properties of the Frozen Waves can find application even in many medical apparatus, such as bistouries or acoustic tweezers, as well as for treatment of diseased tissues (in particular, for the destruction of tumor cells, without affecting the surrounding tissues; also for kidney stone shuttering, etc.). Copyright © 2014 Elsevier B.V. All rights reserved.

Cybersecurity Framework for Ship Industrial Control System

OpenAIRE

Maule, R. William; Hake, Joseph

2016-01-01

Ship mechanical and electrical control systems, and the communications grid through which these devices operate, are a high priority concern for Navy leadership. Ship systems use microprocessor-based controls to interface with physical objects, and Programmable Logic Controllers (PLCs) to automate ship electromechanical processes. Ship operations are completely dependent on these devices. The commercial security products upon which ships depend do not work on ICS, leaving ships vulnerable. Th...

Real-Time Simulation of Ship-Structure and Ship-Ship Interaction

DEFF Research Database (Denmark)

Lindberg, Ole; Glimberg, Stefan Lemvig; Bingham, Harry B.

2013-01-01

, because it is simple, easy to implement and computationally efficient. Multiple many-core graphical processing units (GPUs) are used for parallel execution and the model is implemented using a combination of C/C++, CUDA and MPI. Two ship hydrodynamic cases are presented: Kriso Container Carrier at steady...

A POSSIBLE SOLUTION WITH PASSIVE PROTECTION STRUCTURAL RESISTANCE ELEMENTS TO CARGO SHIPS

Directory of Open Access Journals (Sweden)

MUNTEANU Ildikó Renata

2014-09-01

Full Text Available The authors are proposing an additional fire protection solution (semi-passive for cargo ships, by inserting in the tubular strength structure (hollow section, some rectangular, thin wall pipes manufactured of copper alloy, filled with cooling fluid, that, once the fire bursts, it will be activated (i.e. will be pumped into a closed circuit; this closed system contains also a well dimensioned radiator. This innovative solution could bring improvements with regard to the classic one, of intumescent paints, by extending the safe period for evacuating people and goods.

EX1001 Ship Shakedown (EX1001, EM302) on NOAA Ship Okeanos Explorer in Hawaiian Islands

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The ship has been alongside for repairs and leave since November, 2009. The ship shakedown cruise is scheduled to provide an opportunity for the ship to get underway...

The development of natural circulation operation support program for ship nuclear power machinery

International Nuclear Information System (INIS)

Hao, Jianli; Chen, Wenzhen; Chen, Zhiyun

2012-01-01

Highlights: ► The natural circulation under various ocean and ship motion conditions is studied. ► A natural circulation operation support computer program (NCOSP) is developed with Simulink. ► The NCOSP program has the merit of easy input preparation, fast and accurate simulation. ► The NCOSP is suitable for the fast parameter simulation of ship nuclear power machinery. -- Abstract: The existing simulation program of ship nuclear power machinery (SNPM) cannot adequately deal with the natural circulation (NC) operation and the effects of various ocean conditions and ship motion. Aiming at the problem, the natural circulation operation support computer program for SNPM is developed, in which the momentum conservation equation of the primary loop, some heat transfer and flow resistance models and equations are modified for the various ocean conditions and ship motion. The additional pressure loss model and effective height model for the control volume in the gyration movement, simple harmonic rolling and pitching movements are also discussed in the paper. Furthermore, the transient response to load change under NC conditions is analyzed by the developed program. The results are compared with those predicted by the modified RELAP5/mod3.2 code. It is shown that the natural circulation operation support program (NCOSP) is simple in the input preparation, runs fast and has a satisfactory precision, and is therefore very suitable for the operating field support of SNPM under the conditions of NC.

Corrosion monitoring using high-frequency guided waves

Science.gov (United States)

Fromme, P.

2016-04-01

Corrosion can develop due to adverse environmental conditions during the life cycle of a range of industrial structures, e.g., offshore oil platforms, ships, and desalination plants. Generalized corrosion leading to wall thickness loss can cause the reduction of the strength and thus degradation of the structural integrity. The monitoring of corrosion damage in difficult to access areas can be achieved using high frequency guided waves propagating along the structure from accessible areas. Using standard ultrasonic wedge transducers with single sided access to the structure, guided wave modes were selectively generated that penetrate through the complete thickness of the structure. The wave propagation and interference of the different guided wave modes depends on the thickness of the structure. Laboratory experiments were conducted for wall thickness reduction due to milling of the steel structure. From the measured signal changes due to the wave mode interference the reduced wall thickness was monitored. Good agreement with theoretical predictions was achieved. The high frequency guided waves have the potential for corrosion damage monitoring at critical and difficult to access locations from a stand-off distance.

46 CFR 148.02-1 - Shipping papers.

Science.gov (United States)

2010-10-01

... 46 Shipping 5 2010-10-01 2010-10-01 false Shipping papers. 148.02-1 Section 148.02-1 Shipping... MATERIALS IN BULK Vessel Requirements § 148.02-1 Shipping papers. (a) Carriers may not accept for..., unless the hazardous materials offered for such shipment is accompanied by a shipping paper on which the...

Naval Ship Database: Database Design, Implementation, and Schema

Science.gov (United States)

2013-09-01

ClassId Class identifier Name Ship name Pendant Ship pendant CommissionDate Ship commission date DecommissionDate Ship decommission date; NULL if still...active FlagshipId Ship Id of the ship Figure 3: Ship table definition Table 3: Ship table example rows Id Prefix ClassId Name Pendant ...computation if required. A bridged connection will allow computation analysis to be done in Matlab and allow the processed data to be imported back

Ship Technology Workshop Materials from Collaboration with Mexico to Reduce Emissions from Ships

Science.gov (United States)

On September 26, 2012, a ship technology seminar was held to provide Mexican stakeholders with information about some of the ship technologies needed to meet the requirements of MARPOL Annex VI and an ECA.

Fast ship

OpenAIRE

Keuning, J.A.

2014-01-01

The invention concerns a ship whereby the hull and the mechanical propulsion device are designed such that the Froude number is larger than 0.5. In the aft ship the hull has a bottom with V-shaped bottom surfaces with a deadrise angle that is less than 40 degrees and the hull has substantially vertical sides. In the hull are a passenger compartment and a trim tank. The trim tank volume is such that the weight of a filled trim tank is more than 30 % of the weight of displacement of the hull wi...

46 CFR 151.45-7 - Shipping papers.

Science.gov (United States)

2010-10-01

... 46 Shipping 5 2010-10-01 2010-10-01 false Shipping papers. 151.45-7 Section 151.45-7 Shipping... BULK LIQUID HAZARDOUS MATERIAL CARGOES Operations § 151.45-7 Shipping papers. Each barge carrying... towing vessel shall either have a copy of the shipping papers for each barge in his tow or he shall make...

The investigation of ship maneuvering with hydrodynamic effects between ships in curved narrow channel

Directory of Open Access Journals (Sweden)

Chun-Ki Lee

2016-01-01

Full Text Available The hydrodynamic interaction between two large vessels can't be neglected when two large vessels are closed to each other in restricted waterways such as in a harbor or narrow channel. This paper is mainly concerned with the ship maneuvering motion based on the hydrodynamic interaction effects between two large vessels moving each other in curved narrow channel. In this research, the characteristic features of the hydrodynamic interaction forces between two large vessels are described and illustrated, and the effects of velocity ratio and the spacing between two vessels are summarized and discussed. Also, the Inchon outer harbor area through the PALMI island channel in Korea was selected, and the ship maneuvering simulation was carried out to propose an appropriate safe speed and distance between two ships, which is required to avoid sea accident in confined waters. From the inspection of this investigation, it indicates the following result. Under the condition of SP12≤0.5L, it may encounter a dangerous tendency of grounding or collision due to the combined effect of the interaction between ships and external forces. Also considering the interaction and wind effect as a parameter, an overtaken and overtaking vessel in narrow channel can navigate while keeping its own original course under the following conditions; the lateral separation between two ships is about kept at 0.6 times of ship length and 15 degrees of range in maximum rudder angle. On the other hand, two ships while overtaking in curved narrow channel such as Inchon outer harbor in Korea should be navigated under the following conditions; SP12 is about kept at 1.0 times of ship length and the wind velocity should not be stronger than 10 m/s.

Optimization in liner shipping

DEFF Research Database (Denmark)

Brouer, Berit Dangaard; Karsten, Christian Vad; Pisinger, David

2017-01-01

Seaborne trade is the lynchpin in almost every international supply chain, and about 90% of non-bulk cargo worldwide is transported by container. In this survey we give an overview of data-driven optimization problems in liner shipping. Research in liner shipping is motivated by a need for handling...... still more complex decision problems, based on big data sets and going across several organizational entities. Moreover, liner shipping optimization problems are pushing the limits of optimization methods, creating a new breeding ground for advanced modelling and solution methods. Starting from liner...... shipping network design, we consider the problem of container routing and speed optimization. Next, we consider empty container repositioning and stowage planning as well as disruption management. In addition, the problem of bunker purchasing is considered in depth. In each section we give a clear problem...

Ship construction and welding

CERN Document Server

Mandal, Nisith R

2017-01-01

This book addresses various aspects of ship construction, from ship types and construction materials, to welding technologies and accuracy control. The contents of the book are logically organized and divided into twenty-one chapters. The book covers structural arrangement with longitudinal and transverse framing systems based on the service load, and explains basic structural elements like hatch side girders, hatch end beams, stringers, etc. along with structural subassemblies like floors, bulkheads, inner bottom, decks and shells. It presents in detail double bottom construction, wing tanks & duct keels, fore & aft end structures, etc., together with necessary illustrations. The midship sections of various ship types are introduced, together with structural continuity and alignment in ship structures. With regard to construction materials, the book discusses steel, aluminum alloys and fiber reinforced composites. Various methods of steel material preparation are discussed, and plate cutting and form...

Potential of biofuels for shipping. Final Report

Energy Technology Data Exchange (ETDEWEB)

Florentinus, A.; Hamelinck, C.; Van den Bos, A.; Winkel, R.; Cuijpers, M. [Ecofys Netherlands, Utrecht (Netherlands)

2012-01-15

Biofuels could be one of the options to realize a lower carbon intensity in the propulsion of ships and also possibly reduce the effect of ship emissions on local air quality. Therefore, EMSA, the European Maritime Safety Agency, is evaluating if and how biofuels could be used in the shipping sector as an alternative fuel. To determine the potential of biofuels for ships, a clearer picture is needed on technical and organizational limitations of biofuels in ships, both on board of the ship as in the fuel supply chain to the ship. Economic and sustainability analysis of biofuels should be included in this picture, as well as an overview on current and potential policy measures to stimulate the use of biofuels in shipping. Ecofys has determined the potential of biofuels, based on analysis of collected data through literature review, own expertise and experiences, direct communication with EMSA, research publications, market developments based on press and other media, and consultations with relevant stakeholders in the shipping market.

Development of a Shipboard Remote Control and Telemetry Experimental System for Large-Scale Model’s Motions and Loads Measurement in Realistic Sea Waves

Directory of Open Access Journals (Sweden)

Jialong Jiao

2017-10-01

Full Text Available Wave-induced motion and load responses are important criteria for ship performance evaluation. Physical experiments have long been an indispensable tool in the predictions of ship’s navigation state, speed, motions, accelerations, sectional loads and wave impact pressure. Currently, majority of the experiments are conducted in laboratory tank environment, where the wave environments are different from the realistic sea waves. In this paper, a laboratory tank testing system for ship motions and loads measurement is reviewed and reported first. Then, a novel large-scale model measurement technique is developed based on the laboratory testing foundations to obtain accurate motion and load responses of ships in realistic sea conditions. For this purpose, a suite of advanced remote control and telemetry experimental system was developed in-house to allow for the implementation of large-scale model seakeeping measurement at sea. The experimental system includes a series of technique sensors, e.g., the Global Position System/Inertial Navigation System (GPS/INS module, course top, optical fiber sensors, strain gauges, pressure sensors and accelerometers. The developed measurement system was tested by field experiments in coastal seas, which indicates that the proposed large-scale model testing scheme is capable and feasible. Meaningful data including ocean environment parameters, ship navigation state, motions and loads were obtained through the sea trial campaign.

Thermo-hydraulic characteristics of ship propulsion reactor in the conditions of ship motions and safety assessment

International Nuclear Information System (INIS)

Kobayashi, Michiyuki; Aya, Izuo; Inasaka, Fujio; Murata, Hiroyuki; Odano, Naoteru; Shiozaki, Koki

1998-01-01

A research project from 1995-1999 had a plan to make experimental studies on (1) safety of nuclear ship loaded with an integral ship propulsion reactor (2) effects of pulsating flow on the thermo-hydraulic characteristics of ship propulsion reactor and (3) thermo-hydraulic behaviors of the reactor container at the time of accident in a passively safe ship propulsion reactor. Development of a data base for ship propulsion reactor was attempted using previous experimental data on the thermo-hydraulic characteristics of the reactor in the institute in addition to the present results aiming to make general analytical evaluation for the safety of the engineering-simulation system for nuclear ship. A general data base was obtained by integrating the data list and the analytical program for static characteristics. A test equipment which allows to visualize the pulsating flow was produced and visualization experiments have started. (M.N.)

A Nonlinear Ship Manoeuvering Model: Identification and adaptive control with experiments for a model ship

Directory of Open Access Journals (Sweden)

Roger Skjetne

2004-01-01

Full Text Available Complete nonlinear dynamic manoeuvering models of ships, with numerical values, are hard to find in the literature. This paper presents a modeling, identification, and control design where the objective is to manoeuver a ship along desired paths at different velocities. Material from a variety of references have been used to describe the ship model, its difficulties, limitations, and possible simplifications for the purpose of automatic control design. The numerical values of the parameters in the model is identified in towing tests and adaptive manoeuvering experiments for a small ship in a marine control laboratory.

The Red Sea: An Arena for Wind-Wave Modeling in Enclosed Seas

KAUST Repository

Langodan, Sabique

2016-01-01

weather and climate is crucial for a wide range of applications, including oceanographic studies, maritime activities and ocean engineering. Despite being one of the important world shipping routes, the wind-wave characteristics in the Red Sea are yet

Effect of Buffer Bow Structure in Ship-Ship Collision

DEFF Research Database (Denmark)

Yamada, Yasuhira; Endo, Hisayoshi; Pedersen, Preben Terndrup

2008-01-01

tankers, the introduction of buffer bulbous bows has been proposed. Relatively soft buffer bows absorb part of the kinetic energy of the striking ship before penetrating the inner hull of the struck vessel. The purpose of the present paper is to verify the effectiveness of a prototype buffer bulbous bow......) and the forward velocity of the struck ship on the collapse mode of the bow of the striking vessel are investigated. Collapse modes, contact forces and energy absorption capabilities of the buffer bows are compared with those of conventional bows....

Identification of Dynamically Positioned Ships

Directory of Open Access Journals (Sweden)

Thor I. Fossen

1996-04-01

Full Text Available Todays model-based dynamic positioning (DP systems require that the ship and thruster dynamics are known with some accuracy in order to use linear quadratic optical control theory. However, it is difficult to identify the mathematical model of a dynamically posititmed (DP ship since the ship is not persistently excited under DP. In addition the ship parameter estimation problem is nonlinear and multivariable with only position and thruster state measurements available for parameter estimation. The process and measurement noise must also be modeled in order to avoid parameter drift due to environmental disturbances and sensor failure. This article discusses an off-line parallel extended Kalman filter (EKF algorithm utilizing two measurement series in parallel to estimate the parameters in the DP ship model. Full-scale experiments with a supply vessel are used to demonstrate the convergence and robustness of the proposed parameter estimator.

Toroidal Dielectric Tensor-Operator for Arbitrary Aspect-Ratio and Wave Frequency an Anisotropic-Resistivity MHD Formulation

International Nuclear Information System (INIS)

Komoshvili, K.; Cuperman, S.

1998-01-01

Motivated by the recently increased interest in small aspect ratio tokamaks, we have derived a 2(1/2)D dielectric tensor-operator which can properly describe the plasma response to r.f. waves, under conditions prevailing in the pre-heated stages of arbitrary aspect ratio, axisymmetric toroidal fusion devices. The derived dielectric tensor elements are based on a two-fluid, weakly collisional plasma description, with the Hall term included. They are characterized by the following features: (i) They are cast in a form evidencing the dielectric (non-operator) and operator contributions - the latter being due to the toroidal structure of the V-operators present in Maxwell's equations, on the background of equilibrium currents and pressure gradients; (ii) They are not subject to any I imitation on the (relative) magnitude of the toroidal effects - no expansion in the inverse aspect ratio parameter is used for their derivation; (iii) They include anisotropic - parallel and perpendicular to the magnetic field - contributions to the plasma resistivity; (iv) They are not Iimited by any restriction on the (relative) value of the wave frequency. The explicit, physically transparent formulation of the dielectric tensor is intended for the numerical solution of the full (E ll ≠ 0) wave equation and subsequently, evaluation of the Alfven wave current drive in small aspect ratio tokamaks

Early detection of rogue waves by the wavelet transforms

International Nuclear Information System (INIS)

Bayındır, Cihan

2016-01-01

Highlights: • The advantages of wavelet analysis over the Fourier analysis for the early detection of rogue waves are discussed. • The triangular wavelet spectra can be detected at early stages of the development of rogue waves. • The wavelet analysis is capable of detecting not only the emergence but also the location of a rogue wave. • Wavelet analysis is also capable of predicting the characteristic distances between successive rogue waves. - Abstract: We discuss the possible advantages of using the wavelet transform over the Fourier transform for the early detection of rogue waves. We show that the triangular wavelet spectra of the rogue waves can be detected at early stages of the development of rogue waves in a chaotic wave field. Compared to the Fourier spectra, the wavelet spectra are capable of detecting not only the emergence of a rogue wave but also its possible spatial (or temporal) location. Due to this fact, wavelet transform is also capable of predicting the characteristic distances between successive rogue waves. Therefore multiple simultaneous breaking of the successive rogue waves on ships or on the offshore structures can be predicted and avoided by smart designs and operations.

Early detection of rogue waves by the wavelet transforms

Energy Technology Data Exchange (ETDEWEB)

Bayındır, Cihan, E-mail: cihan.bayindir@isikun.edu.tr

2016-01-08

Highlights: • The advantages of wavelet analysis over the Fourier analysis for the early detection of rogue waves are discussed. • The triangular wavelet spectra can be detected at early stages of the development of rogue waves. • The wavelet analysis is capable of detecting not only the emergence but also the location of a rogue wave. • Wavelet analysis is also capable of predicting the characteristic distances between successive rogue waves. - Abstract: We discuss the possible advantages of using the wavelet transform over the Fourier transform for the early detection of rogue waves. We show that the triangular wavelet spectra of the rogue waves can be detected at early stages of the development of rogue waves in a chaotic wave field. Compared to the Fourier spectra, the wavelet spectra are capable of detecting not only the emergence of a rogue wave but also its possible spatial (or temporal) location. Due to this fact, wavelet transform is also capable of predicting the characteristic distances between successive rogue waves. Therefore multiple simultaneous breaking of the successive rogue waves on ships or on the offshore structures can be predicted and avoided by smart designs and operations.

Analysis of Floating Buoy of a Wave Power Generating Jack-Up Platform Haiyuan 1

Directory of Open Access Journals (Sweden)

Date Li

2013-01-01

Full Text Available The paper focuses on the performance of floating buoys of a wave power generating jack-up platform called Haiyuan 1, in order to work out the optimum designed draft and hydraulic pressure. The performance of the buoy, especially its delivered power, is an important issue in designing oscillating buoy wave energy converter. In this case, major factors affect the performance including incident wave, designed draft, and hydraulic pressure on the buoy. To find out the relationship among design draft, hydraulic pressure, and delivered power, the key point is to precisely estimate wave induced motion of the buoy. Three-dimensional theory and time domain method based on potential theory were adopted in the paper. Unlike ship and other floating structures, motion of wave energy converter (WEC buoy in wave will be weakened because of energy take-off, which will cause significant draft changing with time. Thus, draft changing should be taken into consideration as well. In addition, green water problem occurs more frequently than that in ship and other floating structures and also might the reduce delivered power. Therefore, green water problem will also be taken into account when choosing the optimum designed draft and hydraulic pressure. The calculation indicates that the optimum designed draft is 0.935 m, while the optimum designed hydraulic pressure is 30 kN.

Wave induced extreme hull girder loads on containerships

DEFF Research Database (Denmark)

Jensen, Jørgen Juncher; Pedersen, Preben Terndrup; Shi, Bill

2009-01-01

This paper provides simple but rational procedures for prediction of extreme wave – induced sectional hull girder forces with reasonable engineering accuracy. The procedures take into account main ship hull characteristics such as: length, breadth, draught, block coefficient, bow flare coefficient......, forward speed and hull flexibility. The vertical hull girder loads are evaluated for specific operational profiles. Firstly a quadratic strip theory is presented which can give separate predictions for the hogging and sagging bending moments and shear forces and for hull girder loads. Then this procedure...... is based on rational methods it can be applied for novel single hull ship types not presently covered by the rules of the classification societies or to account for specific operational profiles....

46 CFR 167.05-25 - Nautical school ship.

Science.gov (United States)

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Nautical school ship. 167.05-25 Section 167.05-25 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS PUBLIC NAUTICAL SCHOOL SHIPS Definitions § 167.05-25 Nautical school ship. The term nautical school ship means a vessel operated by or in connection with a nautical school...

Liner Shipping Fleet Repositioning

DEFF Research Database (Denmark)

Tierney, Kevin; Jensen, Rune Møller

2011-01-01

Liner shipping fleet repositioning consists of moving vessels between services in a liner ship- ping network in order to better orient the overall network to the world economy, and to ensure the proper maintenance of vessels. Thus, fleet repositioning involves sailing and loading activities subject...

Hydrodynamics of Ship Propellers

DEFF Research Database (Denmark)

Breslin, John P.; Andersen, Poul

This book deals with flows over propellers operating behind ships, and the hydrodynamic forces and moments which the propeller generates on the shaft and on the ship hull.The first part of the text is devoted to fundamentals of the flow about hydrofoil sections (with and without cavitation...... of an intermittently cavitating propeller in a wake and the pressures and forces it exerts on the shaft and on the ship hull is examined. A final chapter discusses the optimization of efficiency of compound propulsors. The authors have taken care to clearly describe physical concepts and mathematical steps. Appendices...

Development of 1 MW-class HTS motor for podded ship propulsion system

Energy Technology Data Exchange (ETDEWEB)

Umemoto, K; Aizawa, K; Yokoyama, M; Yoshikawa, K [Kawasaki Heavy Industries LTD., 673-8666, Hyogo (Japan); Kimura, Y; Izumi, M [Tokyo University of Marine Science Technology, 135-8533, Tokyo (Japan); Ohashi, K; Numano, M [National Maritime Research Institute, 181-0004, Tokyo (Japan); Okumura, K; Yamaguchi, M; Gocho, Y; Kosuge, E, E-mail: umemoto@ati.khi.co.j [Japan Super-conductivity Organization Co. LTD., 135-8533, Tokyo (Japan)

2010-06-01

To reduce fuel consumption and lead to a major reduction of pollution from NOx, SOx and CO{sub 2}, the electric ship propulsion system is one of the most prospective substitutes for conventional ship propulsion systems. In order to spread it, innovative technologies for the improvement of the power transmission are required. The high temperature superconducting technology has the possibility for a drastic reduction of power transmission loss. Recently, electric podded propulsions have become popular for large cruise vessels, icebreakers and chemical tankers because of the flexibility of the equipment arrangement and the stern hull design, and better maneuverability in harbour, etc. In this paper, a 1 MW-class High temperature superconducting (HTS) motor with high efficiency, smaller size and simple structure, which is designed and manufactured for podded propulsion, is reported. For the case of a coastal ship driven by the optimized podded propulsion in which the 1MW HTS motor is equipped, the reductions of fluid dynamic resistance and power transmission losses are demonstrated. The present research and development has been supported by the New Energy and Industrial Technology Development Organization (NEDO).

International climate policy : consequences for shipping

OpenAIRE

Mæstad, Ottar; Evensen, Annika Jaersen; Mathiesen, Lars; Olsen, Kristian

2000-01-01

This report summarises the main results from the project Norwegian and international climate policy consequences for shipping. The aim of the project has been to shed light on how climate policies might affect shipping, both from the cost side and from the demand side. The project has been divided into three sub-projects, investigating the consequences of climate policies for 1. Optimal shipping operations and management 2. The competitiveness of shipping relative to land transport 3. The tra...

Computational methods for more fuel-efficient ship

NARCIS (Netherlands)

Koren, B.

2008-01-01

The flow of water around a ship powered by a combustion engine is a key factor in the ship's fuel consumption. The simulation of flow patterns around ship hulls is therefore an important aspect of ship design. While lengthy computations are required for such simulations, research by Jeroen Wackers

48 CFR 1371.118 - Changes-ship repair.

Science.gov (United States)

2010-10-01

... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Changes-ship repair. 1371.118 Section 1371.118 Federal Acquisition Regulations System DEPARTMENT OF COMMERCE DEPARTMENT SUPPLEMENTAL REGULATIONS ACQUISITIONS INVOLVING SHIP CONSTRUCTION AND SHIP REPAIR Provisions and Clauses 1371.118 Changes—ship repair. Insert clause...

Some concepts of future nuclear ship

International Nuclear Information System (INIS)

Fujino, Masataka

2000-01-01

Characteristic features of nuclear power generation are as follows: (1) Thermal energy can be continuously extracted for a long time without fuel feed, (2) Nuclear energy is suitable for generating huge power, (3) Oxygen is unnecessary for combustion of fuel, and (4) Unlike fossil fuel, nuclear power generation does not exhaust NOx, SOx, and CO 2 : it can be considered environmentally friendly. In view of these features, the Japan Atomic Energy Research Institute commissioned the Shipbuilding Research Association of Japan (JSRA) to survey what kinds of nuclear ship would be put to practical use in the near future. For this purpose, a research committee was organized in 1992 by the JSRA, and concluded its investigation in 1996. The main aim of this research was to clarify the requirements of ship performance as nuclear ships, and then to extract the technical issues of the marine reactor installed in nuclear ships to be solved. As a result of the survey, it was suggested that displacement-type large high-speed container ship would be one of the promising future nuclear merchant ships, and 6500 m deep-sea and 600 m undersea scientific research submersibles would be other promising nuclear special purpose ships. At the same time, various requirements of marine reactors, which are expected to be installed in these ships, were clarified mainly from the technical viewpoints. (author)

Satellite Eye for the Galathea 3 ship expedition: Global tour 2006-2007

DEFF Research Database (Denmark)

Hasager, Charlotte Bay; Badger, Merete; Sørensen, Peter

2007-01-01

Satellite Eye for Galathea 3 (www.satellitecye.dk contains education at the internet for secondary and upper secondary schools and the public. The Galathea 3 ship expedition circumnavigated the globe starting from Denmark 11 August 2006, visiting Greenland, Azores, South Africa, Australia, Solomon...... of the expedition and these classes in particular used the Satellite Eye teaching material. In Google Earth satellite images of many themes are shown. These include sea ice, sea surface temperature, ocean wind, wave height, sea surface level, ozone, clouds and radar images of ocean and land. Also high spatial...

The Transformation of Swedish Shipping, 1970-2010

OpenAIRE

Sjögren, Hans; Taro Lennerfors, Thomas; Taudal Poulsen, Rene

2012-01-01

Since the early 1970s, as shipping has undergone a period of structural change, Swedish shipping has rapidly declined from a position of global importance. The Swedish-controlled fleet has dwindled, and the structure of the industry itself has changed. This article explores the influence of shipping markets, shipping regulations, company strategies, maritime know-how, and financial resources on the development of Swedish shipping from 1970 to 2010. A comparison is made between, on the one han...

Effective and Safe Ships

DEFF Research Database (Denmark)

Pedersen, Preben Terndrup; Amdahl, Jørgen; Rutgersson, Olle

1996-01-01

A Joint Nordic Research project "Effecive and Safe Ships" is presented. The project is aiming to develop methods and tools for quantitative evaluation fo ship safety. This report is the report of the preliminary phase where the plan for the main project is developed. The objectives of the project...

Analysis of ship life cycles: the impact of economic cycles and ship inspection

NARCIS (Netherlands)

Bijwaard, G.E.; Knapp, S.

2009-01-01

Due to the shipping industry's international legal framework, there are loopholes in the system, which can increase the risk of incidents with high economic costs due to the substandard operation of vessels. This article uses duration analysis and through the creation of ship life cycles provides

46 CFR 173.051 - Public nautical school ships.

Science.gov (United States)

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Public nautical school ships. 173.051 Section 173.051 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SUBDIVISION AND STABILITY SPECIAL RULES PERTAINING TO VESSEL USE School Ships § 173.051 Public nautical school ships. Each public nautical school...

Nonlinear dynamics of resistive electrostatic drift waves

DEFF Research Database (Denmark)

Korsholm, Søren Bang; Michelsen, Poul; Pécseli, H.L.

1999-01-01

The evolution of weakly nonlinear electrostatic drift waves in an externally imposed strong homogeneous magnetic field is investigated numerically in three spatial dimensions. The analysis is based on a set of coupled, nonlinear equations, which are solved for an initial condition which is pertur......The evolution of weakly nonlinear electrostatic drift waves in an externally imposed strong homogeneous magnetic field is investigated numerically in three spatial dimensions. The analysis is based on a set of coupled, nonlinear equations, which are solved for an initial condition which...... polarity, i.e. a pair of electrostatic convective cells....

Field study of dried blood spot specimens for HIV-1 drug resistance genotyping.

Science.gov (United States)

Parry, C M; Parkin, N; Diallo, K; Mwebaza, S; Batamwita, R; DeVos, J; Bbosa, N; Lyagoba, F; Magambo, B; Jordan, M R; Downing, R; Zhang, G; Kaleebu, P; Yang, C; Bertagnolio, S

2014-08-01

Dried blood spots (DBS) are an alternative specimen type for HIV drug resistance genotyping in resource-limited settings. Data relating to the impact of DBS storage and shipment conditions on genotyping efficiency under field conditions are limited. We compared the genotyping efficiencies and resistance profiles of DBS stored and shipped at different temperatures to those of plasma specimens collected in parallel from patients receiving antiretroviral therapy in Uganda. Plasma and four DBS cards from anti-coagulated venous blood and a fifth card from finger-prick blood were prepared from 103 HIV patients with a median viral load (VL) of 57,062 copies/ml (range, 1,081 to 2,964,191). DBS were stored at ambient temperature for 2 or 4 weeks or frozen at -80 °C and shipped from Uganda to the United States at ambient temperature or frozen on dry ice for genotyping using a broadly sensitive in-house method. Plasma (97.1%) and DBS (98.1%) stored and shipped frozen had similar genotyping efficiencies. DBS stored frozen (97.1%) or at ambient temperature for 2 weeks (93.2%) and shipped at ambient temperature also had similar genotyping efficiencies. Genotyping efficiency was reduced for DBS stored at ambient temperature for 4 weeks (89.3%, P = 0.03) or prepared from finger-prick blood and stored at ambient temperature for 2 weeks (77.7%, P blood and handled similarly. Resistance profiles were similar between plasma and DBS specimens. This report delineates the optimal DBS collection, storage, and shipping conditions and opens a new avenue for cost-saving ambient-temperature DBS specimen shipments for HIV drug resistance (HIVDR) surveillances in resource-limited settings. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

Ship emissions and air pollution in Denmark

DEFF Research Database (Denmark)

Olesen, Helge Rørdam; Winther, Morten; Ellermann, Thomas

A project has been carried out to map the contribution from ship traffic to air pollution in Denmark. A main element in the project is the establishment of a new, improved inventory of ship emissions for the waters around Denmark. The inventory makes use of the so-called AIS system, which...... continuously keeps track of ship positions. The inventory provides basis for model calculations of air quality in Denmark for the years 2007, 2011 and 2020. The study has focus on identifying the contribution from ships, and on assessing the effect of international regulations of ship pollution. A minor...... component of the study concerns the contribution to local air pollution from ships at port....

27 CFR 44.187 - Shipping containers.

Science.gov (United States)

2010-04-01

... 27 Alcohol, Tobacco Products and Firearms 2 2010-04-01 2010-04-01 false Shipping containers. 44... Shipping containers. Each shipping case, crate, or other container in which tobacco products, or cigarette... same containers in which they were received from the factory. (72 Stat. 1418, as amended; 26 U.S.C...

27 CFR 44.254 - Shipping containers.

Science.gov (United States)

2010-04-01

... 27 Alcohol, Tobacco Products and Firearms 2 2010-04-01 2010-04-01 false Shipping containers. 44.254 Section 44.254 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU... Requirements § 44.254 Shipping containers. Each shipping case, crate, or other container, in which cigars are...

49 CFR 176.24 - Shipping papers.

Science.gov (United States)

2010-10-01

... 49 Transportation 2 2010-10-01 2010-10-01 false Shipping papers. 176.24 Section 176.24... Requirements § 176.24 Shipping papers. (a) A person may not accept a hazardous material for transportation or transport a hazardous material by vessel unless that person has received a shipping paper prepared in...

49 CFR 177.817 - Shipping papers.

Science.gov (United States)

2010-10-01

... 49 Transportation 2 2010-10-01 2010-10-01 false Shipping papers. 177.817 Section 177.817... Information and Regulations § 177.817 Shipping papers. (a) General requirements. A person may not accept a... received a shipping paper prepared in accordance with part 172 of this subchapter or the material is...

49 CFR 174.24 - Shipping papers.

Science.gov (United States)

2010-10-01

... 49 Transportation 2 2010-10-01 2010-10-01 false Shipping papers. 174.24 Section 174.24... Requirements § 174.24 Shipping papers. (a) A person may not accept a hazardous material for transportation or transport a hazardous material by rail unless that person receives a shipping paper prepared in accordance...

Breaking Waves on the Ocean Surface

Science.gov (United States)

Schwendeman, Michael S.

In the open ocean, breaking waves are a critical mechanism for the transfer of energy, momentum, and mass between the atmosphere and the ocean. Despite much study, fundamental questions about wave breaking, such as what determines whether a wave will break, remain unresolved. Measurements of oceanic breakers, or "whitecaps," are often used to validate the hypotheses derived in simplified theoretical, numerical, or experimental studies. Real-world measurements are also used to improve the parameterizations of wave-breaking in large global models, such as those forecasting climate change. Here, measurements of whitecaps are presented using ship-based cameras, from two experiments in the North Pacific Ocean. First, a method for georectifying the camera imagery is described using the distant horizon, without additional instrumentation. Over the course of the experiment, this algorithm correctly identifies the horizon in 92% of images in which it is visible. In such cases, the calculation of camera pitch and roll is accurate to within 1 degree. The main sources of error in the final georectification are from mislabeled horizons due to clouds, rain, or poor lighting, and from vertical "heave" motions of the camera, which cannot be calculated with the horizon method. This method is used for correcting the imagery from the first experiment, and synchronizing the imagery from the second experiment to an onboard inertial motion package. Next, measurements of the whitecap coverage, W, are shown from both experiments. Although W is often used in models to represent whitecapping, large uncertainty remains in the existing parameterizations. The data show good agreement with recent measurements using the wind speed. Although wave steepness and dissipation are hypothesized to be more robust predictors of W, this is shown to not always be the case. Wave steepness shows comparable success to the wind parameterizations only when using a mean-square slope variable calculated over the

Development of nuclear powered ship in Japan

International Nuclear Information System (INIS)

Sato, Hiroshi

1976-01-01

The development of nuclear merchant ship in Japan was started in 1955 by the establishment of Nuclear Ship Study Group, and since then, the investigation, test and research on nuclear ships have been continued. As a result, a nuclear ocean observation and supply ship was designed for trial. Researches were carried out also in JAERI and Institute for Technical Research of Ships. Meanwhile, the nuclear icebreaker Lenin was completed in Soviet Union in 1959, the nuclear ship Savannah set out for maiden voyage in U.S. in 1962, and the construction of the nuclear ore carrier Otto Hahn was prepared in FRG. Japan Nuclear Ship Development Corp. was established in 1963, and started the design and construction of the first nuclear ship in Japan, Mutsu. The basic policy in the construction is the improvement of nuclear ship technology, the securing of safety, and the use of domestic technologies as far as possible. The progress of the design, construction and test of the Mutsu is described. Owing to the problem of radiation leak, the development of nuclear ships stagnated for a while, but the nuclear plant of the Mutsu demonstrated the expected performance in the functional test, land criticality test and zero output test, and it is expected that the bud of the independent development brought up so far can bear valuable fruit. The independent development of marine nuclear reactors should be continued by selecting the way most suitable to Japan. (Kako, I.)

Ship emissions and their externalities for Greece

Science.gov (United States)

Tzannatos, Ernestos

2010-06-01

The existing and emerging international and European policy framework for the reduction of ship exhaust emissions dictates the need to produce reliable national, regional and global inventories in order to monitor emission trends and consequently provide the necessary support for future policy making. Furthermore, the inventories of ship exhaust emissions constitute the basis upon which their external costs are estimated in an attempt to highlight the economic burden they impose upon the society and facilitate the cost-benefit analysis of the proposed emission abatement technologies, operational measures and market-based instruments prior to their implementation. The case of Greece is of particular interest mainly because the dense ship traffic within the Greek seas directly imposes the impact of its exhaust emission pollutants (NO x, SO 2 and PM) upon the highly populated, physically sensitive and culturally precious Greek coastline, as well as upon the land and seas of Greece in general, whereas the contribution of Greece in the global CO 2 inventory at a time of climatic change awareness cannot be ignored. In this context, this paper presents the contribution of Greece in ship exhaust emissions of CO 2, NO x, SO 2 and PM from domestic and international shipping over the last 25 years (1984-2008), utilizing the fuel-based (fuel sales) emission methodology. Furthermore, the ship exhaust emissions generated within the Greek seas and their externalities are estimated for the year 2008, through utilizing the fuel-based (fuel sales) approach for domestic shipping and the activity-based (ship traffic) approach for international shipping. On this basis, it was found that during the 1984 to 2008 period the fuel-based (fuel sales) ship emission inventory for Greece increased at an average annual rate of 2.85%. In 2008, the CO 2, NO x, SO 2 and PM emissions reached 12.9 million tons (of which 12.4 million tons of CO 2) and their externalities were found to be around 3

ISAR Imaging of Ship Targets Based on an Integrated Cubic Phase Bilinear Autocorrelation Function

Directory of Open Access Journals (Sweden)

Jibin Zheng

2017-03-01

Full Text Available For inverse synthetic aperture radar (ISAR imaging of a ship target moving with ocean waves, the image constructed with the standard range-Doppler (RD technique is blurred and the range-instantaneous-Doppler (RID technique has to be used to improve the image quality. In this paper, azimuth echoes in a range cell of the ship target are modeled as noisy multicomponent cubic phase signals (CPSs after the motion compensation and a RID ISAR imaging algorithm is proposed based on the integrated cubic phase bilinear autocorrelation function (ICPBAF. The ICPBAF is bilinear and based on the two-dimensionally coherent energy accumulation. Compared to five other estimation algorithms, the ICPBAF can acquire higher cross term suppression and anti-noise performance with a reasonable computational cost. Through simulations and analyses with the synthetic model and real radar data, we verify the effectiveness of the ICPBAF and corresponding RID ISAR imaging algorithm.

Report of Nuclear Powered Ship Meeting

International Nuclear Information System (INIS)

1984-01-01

The development of nuclear-powered ships in Japan broke down due to the radiation leak on the nuclear ship ''Mutsu'' in 1974, and the objective has not yet been attained. The Japan Nuclear Ship Research and Development Agency was reorganized to advance the development of nuclear-powered ships and to develop marine nuclear reactors. Recently, various opinions have been expressed regarding the development of nuclear-powered ships and Mutsu, accordingly, it is necessary to clarify the way it should be. The Atomic Energy Commission organized this meeting to discuss the problem. The practical use of nuclear-powered ships is expected at the beginning of the 21st century, but it is only the guess. But it is important to accumulate the technology, knowledge and experience to prepare for the use of nuclear-powered ships. The continuation of the development of Mutsu is important for the future, and the construction of the new home port is unavoidable. The aim of the research and development, and the concrete way of advancing the research and development of Mutsu are discussed. It is scheduled that the Agency is integrated with other atomic energy organizations by March, 1985. The consideration to be given for implementing the integration is described. (Kako, I.)

Reactor dynamics experiment of nuclear ship Mutsu using pseudo random signal (II). The second experiment

International Nuclear Information System (INIS)

Hayashi, Koji; Shimazaki, Junya; Nabeshima, Kunihiko; Ochiai, Masaaki; Shinohara, Yoshikuni; Inoue, Kimihiko.

1995-01-01

In order to investigate dynamics of the reactor plant of the nuclear ship Mutsu, the second reactor noise experiment using pseudo random binary sequences (PRBS) was performed on August 30, 1991 in the third experimental navigation. The experiments using both reactivity and load disturbances were performed at 50% of reactor power and under a quiet sea condition. Each PRBS was applied by manual operation of the control rod or the main steam valve. Various signals of the plant responses and of the acceleration of ship motion were measured. Furthermore, natural reactor noise signals were measured after each PRBS experiment in order to evaluate the effects of the PRBS disturbances. This paper summarizes the planning of the experiment, the instruction for the experiment and logs, the data recording conditions, recorded signal wave forms and the results of power spectral analysis. (author)

Reactor dynamics experiment of nuclear ship Mutsu using pseudo random signal (III). The third experiment

International Nuclear Information System (INIS)

Hayashi, Koji; Shimazaki, Junya; Nabeshima, Kunihiko; Ochiai, Masaaki; Shinohara, Yoshikuni; Inoue, Kimihiko.

1995-03-01

In order to investigate dynamics of the reactor plant of the nuclear ship Mutsu, the third reactor noise experiment using pseudo random binary sequences (PRBS) was performed on September 16, 1991 in the third experimental navigation. The experiments using both reactivity and load disturbances were performed at 70% of reactor power and under a normal sea condition. Each PRBS was applied by manual operation of the control rod or the main steam valve. Various signals of the plant responses and of the acceleration of ship motion were measured. Furthermore, natural reactor noise signals were measured after each PRBS experiment in order to evaluate the effects of the PRBS disturbances. This paper summarizes the planning of the experiment, the instruction for the experiment and logs, the data recording conditions, recorded signal wave forms and the results of power spectral analysis. (author)

19 CFR 4.69 - Shipping articles.

Science.gov (United States)

2010-04-01

... 19 Customs Duties 1 2010-04-01 2010-04-01 false Shipping articles. 4.69 Section 4.69 Customs... VESSELS IN FOREIGN AND DOMESTIC TRADES Foreign Clearances § 4.69 Shipping articles. No vessel of the U.S... officer, of the shipping articles agreements, including any seaman's allotment agreement, required by 46 U...

29 CFR 1915.162 - Ship's boilers.

Science.gov (United States)

2010-07-01

... 29 Labor 7 2010-07-01 2010-07-01 false Ship's boilers. 1915.162 Section 1915.162 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED) OCCUPATIONAL SAFETY AND HEALTH STANDARDS FOR SHIPYARD EMPLOYMENT Ship's Machinery and Piping Systems § 1915.162 Ship's boilers. (a) Before...

Added masses of ship structures

CERN Document Server

Korotkin, Alexandr I

2008-01-01

This essentially self-contained reference book contains data on added masses of ships and various ship and marine engineering structures. Theoretical and experimental methods for determining added masses of these objects are described.

Control mechanisms for Nordic ship emissions

Energy Technology Data Exchange (ETDEWEB)

Martinsen, K. [DNV, Oslo (Norway); Torvanger, A. [Cicero, Oslo (Norway)

2013-04-15

Shipping today operates under a complex set of international and domestic regulations. However, the environmental regulations have lagged behind those of other industries. This situation is now changing quite dramatically. The increased focus on environmental issues, combined with the growing realisation of the actual pollution burden imposed by shipping, has led to an upsurge in both international and national regulations. Some are ready and will enter into force in the near future, while others are still being developed. On behalf of the Nordic Council of Ministers DNV has carried out a study on possible control mechanisms for Nordic ship emission. The aim is to assess the baseline shipping emissions and reduction potential and the possible controlling mechanisms (both incentives and regulations) available for reducing the emissions to air from shipping within the Nordic region. (Author)

Spent fuel shipping cask sealing concepts

International Nuclear Information System (INIS)

Sonnier, C.S.

1989-05-01

In late 1985, the International Atomic Energy Agency (IAEA) requested the US Program for Technical Assistance to IAEA Safeguards (POTAS) to provide a study which examined sealing concepts for application to spent fuel shipping casks. This request was approved, and assigned to Sandia National Laboratories (Sandia). In the course of this study, discussions were held with personnel in the International Safeguards Community who were familiar with the shipping casks used in their States. A number of shipping casks were examined, and discussions were held with two shipping cask manufacturers in the US. As a result of these efforts, it was concluded that the shipping casks provided an extremely good containment, and that many of the existing casks can be effectively sealed by applying the seal to the cask closure bolts/nuts

Numerical and theoretical investigations of resistive drift wave turbulence

International Nuclear Information System (INIS)

Sunn Pedersen, T.

1995-07-01

With regard to the development of thermonuclear fusion utilizing a plasma confined in a magnetic field, anomalous transport is a major problem and is considered to be caused by electrostatic drift wave turbulence. A simplified quasi-two-dimensional slab model of resistive drift wave turbulence is investigated numerically and theoretically. The model (Hasegawa and Wakatani), consists of two nonlinear partial differential equations for the density perturbation n and the electrostatic potential perturbation φ. It includes the effect of a background density gradient perpendicular to the magnetic field and a generalized Ohm's law for the electrons in the direction parallel to the magnetic field. It may be used to model the basic features of electrostatic turbulence and the associated transport in an edge plasma. Model equations are derived and some important properties of the system are discussed. It is described how the Fourier spectral method is applied to the Hasegawa-Wakatani equations, how the time integration is developed to ensure accurate and fast simulations in a large parameter regime, and how the accuracy of the code is checked. Numerical diagnostics are developed to verify and extend the results in publications concerning quasi-stationary turbulent states and to give an overview of the properties of the quasi-stationary turbulent state. The use of analysis tools, not previously applied to the Hasegawa-Wakatani system, and the results obtained are described. Fluid particles are tracked to obtain Lagrangian statistics for the turbulence. A new theoretical analysis of relative dispersion leads to a decomposition criterion for the particles. The significance of this is investigated numerically and characteristic time scales for particles are determined for a range of parameter values. It is indicated that the turbulent state can be characterized in the context of nonlinear dynamics and chaos theory as an attractor with a large basin of attraction. The basic

Development of a nuclear ship safety philosophy

International Nuclear Information System (INIS)

Thompson, T.E.

1978-01-01

A unique safety philosophy must be recognized and accepted as an integral part of the design and operation of a nuclear ship. For the nuclear powered ship, the ultimate safety of the reactor and therefore the crew and the environment lies with the safety of the ship itself. The basis for ship safety is its ability to navigate and survive the conditions or the environment in which it may find itself. The subject of traditional ship safety is examined along with its implication for reactor protection and safety. Concepts of reactor safety are also examined. These two philosophies are combined in a manner so as to provide a sound philosophy for the safety of nuclear ships, their crews, and the environment

International Conference on Numerical Ship Hydrodynamics (2nd) Held in Berkeley, California on 19-21 September 1977

Science.gov (United States)

1977-09-01

ORDERING INFORMATION Sec d Internat nal Contere ce on Nu erical Ship ydro nermics ay be order by mallin a req~uest the folio ng ad ess: Firt ilererin I...f(x)dx - 0 (f ’ J d Gd(x’,X 3) dx’ -D0 (jx) 0 d.’ d’U is a closed subspacs of aUoxV ’XT,. hence I O Gde Loach space. d o l , Aw D(4 (x U ’!’ ) Proofs...crest of unbro- domain as an initial-value problem advancing in Ken waves. The inception of wave breaking is time until a steady-state condition has

A novel methodology for adaptive wave filtering of marine vessels: Theory and experiments

Digital Repository Service at National Institute of Oceanography (India)

Hassani, V.; Pascoal, A.M.; Sorensen, A.J.

This paper addresses a filtering problem that arises in the design of dynamic positioning systems for ships and offshore rigs subjected to the influence of sea waves. The vessel`s dynamic model adopted captures the sea state as an uncertain...

15 CFR 750.11 - Shipping tolerances.

Science.gov (United States)

2010-01-01

... in the ECCN applicable to your item reads “ $ value” or “in $ value”, there is no shipping tolerance... is no shipping tolerance with respect to the number of units. However, the value of all of your... shipping tolerance on this license because the items are controlled by an ECCN where “$ value” is the...

Ship design methodologies of preliminary design

CERN Document Server

Papanikolaou, Apostolos

2014-01-01

This book deals with ship design and in particular with methodologies of the preliminary design of ships. The book is complemented by a basic bibliography and five appendices with useful updated charts for the selection of the main dimensions and other basic characteristics of different types of ships (Appendix A), the determination of hull form  from the data of systematic hull form series (Appendix B), the detailed description of the relational method for the preliminary estimation of ship weights (Appendix C), a brief review of the historical evolution of shipbuilding science and technology from the prehistoric era to date (Appendix D) and finally a historical review of regulatory developments of ship's damage stability to date (Appendix E).  The book can be used as textbook for ship design courses or as additional reading for university or college students of naval architecture courses and related disciplines; it may also serve as a reference book for naval architects, practicing engineers of rel...

Potential risks of nuclear ships

International Nuclear Information System (INIS)

Oelgaard, P.L.

1994-07-01

This report represents an attempt to evaluate the potential risks of nuclear ships. Firstly reasons are given why nuclear ship accidents will not lead to accidents of the magnitude of the Chernobyl accident. This is due to much lower content of radioactive material and to different reactor designs. Next a review is given of the types of accidents which have actually occurred. Of these the reactor accidents which may lead to serious consequences for the crew and the environment are considered further. These are reactivity accidents and loss of coolant accidents. In addition the long term risks of sunken nuclear ships and sea disposed reactor compartments etc. are also discussed. Based on available accident data an attempt is made to estimate the probability of serious nuclear ship accidents. (au)

Occupational accidents aboard merchant ships

DEFF Research Database (Denmark)

Hansen, H.L.; Nielsen, D.; Frydenberg, Morten

2002-01-01

Objectives: To investigate the frequency, circumstances, and causes of occupational accidents aboard merchant ships in international trade, and to identify risk factors for the occurrence of occupational accidents as well as dangerous working situations where possible preventive measures may...... be initiated. Methods: The study is a historical follow up on occupational accidents among crew aboard Danish merchant ships in the period 1993–7. Data were extracted from the Danish Maritime Authority and insurance data. Exact data on time at risk were available. Results: A total of 1993 accidents were...... aboard. Relative risks for notified accidents and accidents causing permanent disability of 5% or more were calculated in a multivariate analysis including ship type, occupation, age, time on board, change of ship since last employment period, and nationality. Foreigners had a considerably lower recorded...

Impact of acoustic impedance and flow resistance on the power output capacity of the regenerators in travelling-wave thermoacoustic engines

International Nuclear Information System (INIS)

Yu Zhibin; Jaworski, Artur J.

2010-01-01

This paper considers the role of acoustic impedance, flow resistance, configuration and geometrical dimensions of regenerators on the power produced in travelling-wave thermoacoustic engines. The effects are modelled assuming a pure travelling-wave and ideal gas, which allows defining a pair of dimensionless factors based on the 'net' acoustic power production. Based on the analysis provided, the acoustic power flow in the regenerators is investigated numerically. It is shown that impedance essentially reflects the proportion between the acoustic power produced from heat energy through the thermoacoustic processes and the acoustic power dissipated by viscous and thermal-relaxation effects in the regenerators. Viscous resistance of the regenerator mainly determines the magnitude of the volumetric velocity and then affects the magnitude of acoustic impedance. High impedance and high volumetric velocity are both required in the regenerators for high power engines. The results also show that the optimum transverse dimension of the gas passage exists, but depends on the local acoustic impedance. In principle, it is possible to obtain an optimum combination between these two parameters.

Concept Design and Risk Assessment of Nuclear Propulsion Ship

International Nuclear Information System (INIS)

Gil, Youngmi; Yoo, Seongjin; Kim, Yeontae; Oh, June; Byun, Yoonchul; Woo, Ilguk; Kim, Jiho; Choi, Suhn

2014-01-01

The nuclear propulsion ships (hereinafter referred to as 'nuclear ships') have been considered as an eco-friendly ship. There have historically been warship and submarine with the source of nuclear power. The use of nuclear ships has been recently extending to the icebreaker, the deep-water exploration ship, and the floating nuclear power plant. Prior to developing the new ship, we evaluated the economics of various types of ships and concluded that the container ship could be appropriate for the nuclear propulsion. In order to verify its safety, we performed the ship calculation based on the optimal arrangement of the nuclear reactor. Finally, we verified its safety by the HAZID. In the former research, we confirmed the applicability of the nuclear propulsion system for the large container ship. In this study, we verified the safety of the nuclear ships according to the HAZID analysis. We expect that this research will lead to safe design of the nuclear ships

Concept Design and Risk Assessment of Nuclear Propulsion Ship

Energy Technology Data Exchange (ETDEWEB)

Gil, Youngmi; Yoo, Seongjin; Kim, Yeontae; Oh, June; Byun, Yoonchul; Woo, Ilguk [Daewoo Shipbuilding and Marine Engineering Co. Ltd., Seoul (Korea, Republic of); Kim, Jiho; Choi, Suhn [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2014-05-15

The nuclear propulsion ships (hereinafter referred to as 'nuclear ships') have been considered as an eco-friendly ship. There have historically been warship and submarine with the source of nuclear power. The use of nuclear ships has been recently extending to the icebreaker, the deep-water exploration ship, and the floating nuclear power plant. Prior to developing the new ship, we evaluated the economics of various types of ships and concluded that the container ship could be appropriate for the nuclear propulsion. In order to verify its safety, we performed the ship calculation based on the optimal arrangement of the nuclear reactor. Finally, we verified its safety by the HAZID. In the former research, we confirmed the applicability of the nuclear propulsion system for the large container ship. In this study, we verified the safety of the nuclear ships according to the HAZID analysis. We expect that this research will lead to safe design of the nuclear ships.

Automatic temperature control method of shipping can

International Nuclear Information System (INIS)

Nishikawa, Kaoru.

1992-01-01

The present invention provides a method of rapidly and accurately controlling the temperature of a shipping can, which is used upon shipping inspection for a nuclear fuel assembly. That is, a measured temperature value of the shipping can is converted to a gas pressure setting value in a jacket of the shipping can by conducting a predetermined logic calculation by using a fuzzy logic. A gas pressure control section compares the pressure setting value of a fuzzy estimation section and the measured value of the gas pressure in the jacket of the shipping can, and conducts air supply or exhaustion of the jacket gas so as to adjust the measured value with the setting value. These fuzzy estimation section and gas pressure control section control the gas pressure in the jacket of the shipping can to control the water level in the jacket. As a result, the temperature of the shipping can is controlled. With such procedures, since the water level in the jacket can be controlled directly and finely, temperature of the shipping can is automatically controlled rapidly and accurately compared with a conventional case. (I.S.)

Projections of wind-waves in South China Sea for the 21st century

Science.gov (United States)

Mohammed, Aboobacker; Dykyi, Pavlo; Zheleznyak, Mark; Tkalich, Pavel

2013-04-01

IPCC-coordinated work has been completed within Fourth Assessment Report (AR4) to project climate and ocean variables for the 21st century using coupled atmospheric-ocean General Circulation Models (GCMs). GCMs are not having a wind-wave variable due to a poor grid resolution; therefore, dynamical downscaling of wind-waves to the regional scale is advisable using well established models, such as Wave Watch III (WWIII) and SWAN. Rectilinear-coordinates WWIII model is adapted for the far field comprising the part of Pacific and Indian Oceans centered at the South China Sea and Sunda Shelf (90 °E-130 °E, 10 °S - 26.83 °N) with a resolution of 10' (about 18 km). Near-field unstructured-mesh SWAN model covers Sunda Shelf and centered on Singapore Strait, while reading lateral boundary values from WWIII model. The unstructured grid has the coarsest resolution in the South China Sea (6 to 10 km), medium resolution in the Malacca Strait (1 to 2 km), and the finest resolution in the Singapore Strait (400 m) and along the Singapore coastline (up to 100 m). Following IPCC methodology, the model chain is validated climatologically for the past period 1961-1990 against Voluntary Observing Ship (VOS) data; additionally, the models are validated using recent high-resolution satellite data. The calibrated model chain is used to project waves to 21st century using WRF-downscaled wind speed output of CCSM GCM run for A1FI climate change scenario. To comply with IPCC methodology the entire modeling period is split into three 30-years periods for which statistical parameters are computed individually. Time series of significant wave height at key points near Singapore and on ship sea routes in the SCS are statistically analysed to get probability distribution functions (PDFs) of extreme values. Climatological maps of mean and maximum significant wave height (SWH) values, and mean wave period are built for Singapore region for each 30-yrs period. Linear trends of mean SWH values

Ship Observations - VOS and Navy

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Combination of Voluntary Observing Ship (VOS) and US Navy Ship weather observations. Obs generally taken 2-4 times daily at 00, 06, 12, and 18z.

An analytical method to assess the damage and predict the residual strength of a ship in a shoal grounding accident scenario

Directory of Open Access Journals (Sweden)

Sun Bin

2016-04-01

Full Text Available In this paper, a simplified analytical method used to predict the residual ultimate strength of a ship hull after a shoal grounding accident is proposed. Shoal grounding accidents always lead to severe denting, though not tearing, of the ship bottom structure, which may threaten the global hull girder resistance and result in even worse consequences, such as hull collapse. Here, the degree of damage of the bottom structure is predicted by a series of analytical methods based on the plastic-elastic deformation mechanism. The energy dissipation of a ship bottom structure is obtained from individual components to determine the sliding distance of the seabed obstruction. Then, a new approach to assess the residual strength of the damaged ship subjected to shoal grounding is proposed based on the improved Smith's method. This analytical method is verified by comparing the results of the proposed method and those generated by numerical simulation using the software ABAQUS. The proposed analytical method can be used to assess the safety of a ship with a double bottom during its design phase and predict the residual ultimate strength of a ship after a shoal grounding accident occurs.

Shipping Fairways

Data.gov (United States)

Department of Homeland Security — Various shipping zones delineate activities and regulations for marine vessel traffic. Traffic lanes define specific traffic flow, while traffic separation zones...

Navy Ships: Turning Over Auxiliary Ship Operations to the Military Sealift Command Could Save Millions

National Research Council Canada - National Science Library

1997-01-01

.... One additional multiproduct ship of a new class is currently under construction. The Navy has delegated operational control of 27 of these ships to MSC, the military's single manager for sealift, to better...

Update on emissions and environmental impacts from the international fleet of ships: the contribution from major ship types and ports

Directory of Open Access Journals (Sweden)

S. B. Dalsøren

2009-03-01

Full Text Available A reliable and up-to-date ship emission inventory is essential for atmospheric scientists quantifying the impact of shipping and for policy makers implementing regulations and incentives for emission reduction. The emission modelling in this study takes into account ship type and size dependent input data for 15 ship types and 7 size categories. Global port arrival and departure data for more than 32 000 merchant ships are used to establish operational profiles for the ship segments. The modelled total fuel consumption amounts to 217 Mt in 2004 of which 11 Mt is consumed in in-port operations. This is in agreement with international sales statistics. The modelled fuel consumption is applied to develop global emission inventories for CO₂, NO₂, SO₂, CO, CH₄, VOC (Volatile Organic Compounds, N₂O, BC (Black Carbon and OC (Organic Carbon. The global emissions from ships at sea and in ports are distributed geographically, applying extended geographical data sets covering about 2 million global ship observations and global port data for 32 000 ships. In addition to inventories for the world fleet, inventories are produced separately for the three dominating ship types, using ship type specific emission modelling and traffic distributions.

A global Chemical Transport Model (CTM was used to calculate the environmental impacts of the emissions. We find that ship emissions is a dominant contributor over much of the world oceans to surface concentrations of NO₂ and SO₂. The contribution is also large over some coastal zones. For surface ozone the contribution is high over the oceans but clearly also of importance over Western North America (contribution 15–25% and Western Europe (5–15%. The contribution to tropospheric column ozone is up to 5–6%. The overall impact of ship emissions on global methane lifetime is large due to the high NO_x emissions. With

Ships going slow in reducing their NOx emissions: changes in 2005-2012 ship exhaust inferred from satellite measurements over Europe

Science.gov (United States)

Folkert Boersma, K.; Vinken, Geert C. M.; Tournadre, Jean

2015-07-01

We address the lack of temporal information on ship emissions, and report on rapid short-term variations of satellite-derived ship NOx emissions between 2005 and 2012 over European seas. Our inversion is based on OMI observed tropospheric NO2 columns and GEOS-Chem simulations. Average European ship NOx emissions increased by ˜15% from 2005 to 2008. This increase was followed by a reduction of ˜12% in 2009, a direct result of the global economic downturn in 2008-2009, and steady emissions from 2009 to 2012. Observations of ship passages through the Suez Canal and satellite altimeter derived ship densities suggests that ships in the Mediterranean Sea have reduced their speed by more than 30% since 2008. This reduction in ship speed is accompanied by a persistent 45% reduction of average, per ship NOx emission factors. Our results indicate that the practice of ‘slow steaming’, i.e. the lowering of vessel speed to reduce fuel consumption, has indeed been implemented since 2008, and can be detected from space. In spite of the implementation of slow steaming, one in seven of all NOx molecules emitted in Europe in 2012 originated from the shipping sector, up from one in nine in 2005. The growing share of the shipping contributions to the overall European NOx emissions suggests a need for the shipping sector to implement additional measures to reduce pollutant emissions at rates that are achieved by the road transport and energy producing sectors in Europe.

Study of Volatility of New Ship Building Prices in LNG Shipping

Directory of Open Access Journals (Sweden)

T. Bangar Raju

2016-12-01

Full Text Available The natural gas market has been expanding in size and has attracted particular attention across the global energy market. Although most natural gas transportation is carried out through pipelines, almost one third of it is done with the help of merchant vessels, capable of carrying liquefied natural gas. These LNG carriers have a special design and thus can be treated as a separate class of global fleet. New vessels are huge capital investments by vessel owning companies and just like other vessel classes; the new shipbuilding prices for the LNG segment continue to be a key aspect in the decision making of business players. Additionally these prices can be volatile as new ship building prices fluctuate with time. This paper attempts to analyse the volatility of new ship building prices of LNG carriers. For the study, the average ship building prices for all the LNG carriers having volume carrying capacity is between 160,000 – 173,000 cbm to be delivered between 2016 – 2019 were taken into account. For the analysis, GARCH and EGARCH methods were applied on the data set. The analysis concluded that there is a great deal of volatility in the new ship building prices of LNG vessels. It was also identified that negative shocks were more persistent the positive shocks.

Evaluation of the Service Performance of Ships

DEFF Research Database (Denmark)

Andersen, Poul; Borrod, Anne-Sophie; Blanchot, Hervé

2005-01-01

A simple method has been established for the evaluation of the service performance of ships. Input data are easily collected daily on board and transformed to a well-defined condition that makes possible the comparison between ships, for instance, sister ships, and between different time periods...... of voyages for the same ship. The procedure has been applied to two ships that are identical, with the exception that one has a conventional propeller, whereas the other one is fitted with a high-efficiency propeller of the KAPPEL type. The results are obtained from a period of 2 years steaming for both...

46 CFR 160.151-17 - Additional requirements for design and performance of SOLAS A and SOLAS B inflatable liferafts.

Science.gov (United States)

2010-10-01

... stability appendages on its underside to resist capsizing from wind and waves. These appendages must meet...). Means must be provided for identifying the liferaft with the name and port of registry of the ship to...

Transnucleaire's experience in ship adaptation

International Nuclear Information System (INIS)

Brachet, Y.; Vallette-Fontaine, M.

2000-01-01

Due to the application of the new IMDG regulations for the transport of radioactive material by sea, the conditions of transport of MTR spent fuel have drastically changed five years ago. In this paper, TRANSNUCLEAIRE analyses the necessary modifications to apply to existing ships in order to comply with the IMDG/INF regulations as well as with the Japanese KAISA 520 regulation. In the MTR spent fuel transport market characterized by a competitive approach, TRANSNUCLEAIRE has carried out many transports by sea in full compliance with the regulations at a price which is as close as possible to that of other industrial goods and without the need to fully dedicate the BOUGUENAIS ship to nuclear transports. Innovative ship design solutions have been implemented and accepted by different Authorities uncluding the Advisory Committee of the Japanese MOT. Due to efficient finite element calculations, benchmarked by laboratory large scale tests, high performances crushing materials have been developed in order to absorb the energy of collision between ships. These developments have led ta propose an efficient ship design complying with all the existing worldwide nuclear regulations. (author)

Safety analysis report for packaging: neutron shipping cask, model 4T

International Nuclear Information System (INIS)

Peterson, R.T.

1977-01-01

This Safety Analysis Report for Packaging demonstrates that the neutron shipping cask can safely transport, in solid or powder form, all isotopes of uranium, plutonium, americium, curium, berkelium, californium, einsteinium, and fermium. The cask and its contents are described. It also evaluates transport conditions, structural parameters (e.g., load resistance, pressure and impact effects, lifting and tiedown devices), and shielding. Finally, it discusses compliance with Chapter 0529 of the Energy Research and Development Administration Manual, Safety Standards for the Packaging of Fissile and Other Radioactive Materials

Ship-to-Ship Radiocommunication Trial by Using Wireless LAN

Directory of Open Access Journals (Sweden)

Yasuyuki Niwa

2015-12-01

In a former field radiocommunication trial, omni-directional antennas were used and a few hundred kbps throughput between two ships was measured, which was not enough for our research target (over 1Mbps. In order to get faster throughput, a field radiocommunication trial was carried out again with a few types of directional antennas and RSSI (Received Signal Strength Indication and the throughput between two ships was measured simultaneously. As a result, multi-path (2-path model affected by the reflection of the sea surface was confirmed and also the characteristics of the directional antennas such as half-power angle were confirmed, but the measured throughput was fast enough to meet our expectation.

Ship maneuvering digital simulator; Simulador digital de manobras de navios

Energy Technology Data Exchange (ETDEWEB)

Souza Junior, Jesse Rebello; Tannuri, Eduardo Aoun; Oshiro, Anderson Takehiro [Universidade de Sao Paulo (USP), SP (Brazil). Escola Politecnica. Dept. de Engenharia Naval e Oceanica

2008-07-01

This paper reports on two case studies making use of a digital simulator to investigate the maneuvering motions of ships in canals with shallow and restricted waters. The first case study corresponds to a maneuvering analysis conducted for the Port of Rio Grande (RS - Brazil), whose aim was to assess the potential impact upon maneuvers of the presence of a large offshore platform (the PETROBRAS P-53) which is to remain docked for several months at the Port to complete its construction. The second study made use of the simulator to evaluate the maneuvering conditions along the approach route and maneuvering basin of the Port of Ponta do Felix (PR - Brazil). The simulator includes a complete mathematical model of the ship dynamics in the horizontal plane when subjected to wind and current forces. It also comprises detailed models for the action of thrusters and propellers, both fixed and azimuth, employed to control maneuvers and dynamically position ships, as well as rudders and tugboats. He models used by the simulator allow for the effects of shallow and restricted waters, including the increase in resistance and lateral forces, increase in additional mass and the appearance of lateral and vertical suction (squatting). The simulator is implemented via an interactive interface through which the user is able to apply control actions (rudder angle, main engine, thrusters and tugboats) in real time during maneuvers, thereby reproducing to some extent the action of a pilot. (author)

Note from the radioprotection group's shipping service

CERN Multimedia

2006-01-01

The service for the import/export of radioactive materials reminds you that shipping requests for potentially radioactive materials must be made via the EDH request form by ticking the box 'radioactive material'. All the necessary information is given on the web site: http://cern.ch/service-rp-shipping Requests not complying with the above procedure will not be taken into account. Radioactive Shipping Service http://cern.ch/service-rp-shipping Tel. 73171 Fax: 69200

48 CFR 47.305-16 - Shipping characteristics.

Science.gov (United States)

2010-10-01

... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Shipping characteristics... CONTRACT MANAGEMENT TRANSPORTATION Transportation in Supply Contracts 47.305-16 Shipping characteristics... shipments of agreed size. (b) Guaranteed shipping characteristics. (1) The contracting officer shall insert...

Ships - inspiring objects in architecture

Science.gov (United States)

Marczak, Elzbieta

2017-10-01

Sea-going vessels have for centuries fascinated people, not only those who happen to work at sea, but first and foremost, those who have never set foot aboard a ship. The environment in which ships operate is reminiscent of freedom and countless adventures, but also of hard and interesting maritime working life. The famous words of Pompey: “Navigare necesseest, vivere non estnecesse” (sailing is necessary, living - is not necessary), which he pronounced on a stormy sea voyage, arouse curiosity and excitement, inviting one to test the truth of this saying personally. It is often the case, however, that sea-faring remains within the realm of dreams, while the fascination with ships demonstrates itself through a transposition of naval features onto land constructions. In such cases, ship-inspired motifs bring alive dreams and yearnings as well as reflect tastes. Tourism is one of the indicators of people’s standard of living and a measure of a society’s civilisation. Maritime tourism has been developing rapidly in recent decades. A sea cruise offers an insight into life at sea. Still, most people derive their knowledge of passenger vessels and their furnishings from the mass media. Passenger vessels, also known as “floating cities,” are described as majestic and grand, while their on-board facilities as luxurious, comfortable, exclusive and inaccessible to common people on land. Freight vessels, on the other hand, are described as enormous objects which dwarf the human being into insignificance. This article presents the results of research intended to answer the following questions: what makes ships a source of inspiration for land architecture? To what extent and by what means do architects draw on ships in their design work? In what places can we find structures inspired by ships? What ships inspire architects? This article presents examples of buildings, whose design was inspired by the architecture and structural details of sea vessels. An analysis of

India's ship recycling trade-off

NARCIS (Netherlands)

Worrell, E.; Athanasopoulou, V.

2014-01-01

The special nature of India's steel industry lends particular importance to ship recycling as a source of scrap. Ship recycling in upgraded 'green' facilities can substitute other 'dirty' ironmaking processes, resulting in energy savings and air pollutant emission reductions for the Indian steel

SHIPPING REQUESTS ON EDH

CERN Multimedia

Logistics Group

2001-01-01

Users are informed that as from 1 September 2001 all Shipping Requests must be made on EDH using the appropriate electronic form. The submission of user requests directly into EDH will help rationalise the activities of the Shipping Service (Import & Export), with requests being automatically forwarded to hierarchical supervisors thereby improving the processing speed and facilitating the follow-up. Thank you for your collaboration.

A building cost estimation method for inland ships

NARCIS (Netherlands)

Hekkenberg, R.G.

2014-01-01

There is very little publicly available data about the building cost of inland ships, especially for ships that have dimensions that differ significantly from those of common ships. Also, no methods to determine the building cost of inland ships are described in literature. In this paper, a method

Test Ship

Data.gov (United States)

Federal Laboratory Consortium — The U. S. Navy dedicated the decommissioned Spruance Class destroyer ex-PAUL F. FOSTER (EDD 964), Test Ship, primarily for at sea demonstration of short range weapon...

Corrosion monitoring using high-frequency guided ultrasonic waves

Science.gov (United States)

Fromme, Paul

2014-02-01

Corrosion develops due to adverse environmental conditions during the life cycle of a range of industrial structures, e.g., offshore oil platforms, ships, and desalination plants. Both pitting corrosion and generalized corrosion leading to wall thickness loss can cause the degradation of the structural integrity. The nondestructive detection and monitoring of corrosion damage in difficult to access areas can be achieved using high frequency guided waves propagating along the structure from accessible areas. Using standard ultrasonic transducers with single sided access to the structure, guided wave modes were generated that penetrate through the complete thickness of the structure. The wave propagation and interference of the different guided wave modes depends on the thickness of the structure. Laboratory experiments were conducted and the wall thickness reduced by consecutive milling of the steel structure. Further measurements were conducted using accelerated corrosion in a salt water bath and the damage severity monitored. From the measured signal change due to the wave mode interference the wall thickness reduction was monitored. The high frequency guided waves have the potential for corrosion damage monitoring at critical and difficult to access locations from a stand-off distance.

The complex network of global cargo ship movements.

Science.gov (United States)

Kaluza, Pablo; Kölzsch, Andrea; Gastner, Michael T; Blasius, Bernd

2010-07-06

Transportation networks play a crucial role in human mobility, the exchange of goods and the spread of invasive species. With 90 per cent of world trade carried by sea, the global network of merchant ships provides one of the most important modes of transportation. Here, we use information about the itineraries of 16 363 cargo ships during the year 2007 to construct a network of links between ports. We show that the network has several features that set it apart from other transportation networks. In particular, most ships can be classified into three categories: bulk dry carriers, container ships and oil tankers. These three categories do not only differ in the ships' physical characteristics, but also in their mobility patterns and networks. Container ships follow regularly repeating paths whereas bulk dry carriers and oil tankers move less predictably between ports. The network of all ship movements possesses a heavy-tailed distribution for the connectivity of ports and for the loads transported on the links with systematic differences between ship types. The data analysed in this paper improve current assumptions based on gravity models of ship movements, an important step towards understanding patterns of global trade and bioinvasion.

Bio-indications of sunken ships and ship wrecks

Digital Repository Service at National Institute of Oceanography (India)

Parulekar, A

An evaluation of bottom fauna of ship-wreck sites in estuarine and coastal waters of Goa, India, revealed an exceptionally high biotic enrichment. In terms of number of species, faunal dispersion, faunal diversity, biomass and productivity, in space...

Ships and the Sailors Inside Them

National Research Council Canada - National Science Library

Sims, Philip

2004-01-01

.... Iron shipbuilding allowed safer and healthier ships but their internal compartmentation created communication problems which were gradually solved with mechanical systems Ships developed their own...

Retrograde intrarenal stone surgery for extracorporeal shock-wave lithotripsy-resistant kidney stones

DEFF Research Database (Denmark)

Jung, Helene; Nørby, Bettina; Osther, Palle Jörn

2006-01-01

OBJECTIVE: The newer flexible ureteroscopes, 150-200-microm holmium YAG laser fibres and superflexible Dormia baskets have made it possible to reach and treat stones in all parts of the kidney. The object of this evaluation was to study the outcome of retrograde intrarenal stone surgery (RIRS......) for extracorporeal shock-wave lithotripsy (ESWL)-resistant kidney stones. MATERIAL AND METHODS: A total of 38 consecutive patients (18 males, 20 females) participated in the study. All patients had undergone ESWL prior to RIRS without success. In all cases the stones could be reached with the endoscope. Calculi...... ranged in size from 3 to 20 mm (mean 9 mm). In 32 cases the stones were fragmented using a holmium YAG laser and in six the stones could be extracted using zero-tip Dormia baskets without fragmentation. Sixteen patients had lower calyceal calculi and eight had an abnormal anatomy of the upper urinary...

Prototypic fabrication of TRIGA irradiated fuel shipping casks

International Nuclear Information System (INIS)

Kim, B.K.; Lee, Y.W.; Whang, C.K.; Lee, J.B.

1980-01-01

This is the safety analysis report on the prototypic fabrication of ''TRIGA Irradiated Fuel Shipping Cask'' conducted by KAERI in 1980. The results of the evaluation show that the shipping cask is in compliance with the applicable regulation for the normal conditions of transport as well as hypothetical accident conditions. The prototypic fabrication of the shipping cask (type B) was carried out for the first time in Korea after getting technical experience from fabrication of the ''TRIGA Spent Fuel Shipping Cask'' and ''the KO-RI Unit 1 surveillance capsule shipping cask'' in 1979. This report contains structural evaluation, thermal evaluation, shielding, criticality, quality assurance, and handling procedures of the shipping cask

Challenges to Ship Hydrodynamics in the XXI Century

Directory of Open Access Journals (Sweden)

Lech Kobylinski

2014-09-01

Full Text Available The beginning of twenty-first century is characterized with important changes in world shipping and exploitation of ocean resources. Three important trends are clearly visible: environment protection, safety and economy. They materialize in important changes in the structure of world fleet where some existing ship types are going to disappear and new ship types emerge. Increasing the size of some ship types is another visible tendency. Stress on environment protection has serious impact on the hydrodynamic characteristics of ships whether with regard to safety zero accident rate is the goal. Important challenges to ship hydrodynamics caused by those tendencies are discussed in the paper.

Ship operations report, 1975

International Nuclear Information System (INIS)

1976-01-01

The NOAA Ship Operations Report 1975 was developed to provide a summary of projects undertaken during calendar year 1975. The report was prepared from season, cruise and special reports submitted by ships of the fleet. This report is promulgated for inhouse dissemination in the National Oceanic and Atmospheric Administration, for collaborating and interested agencies, and for use by members of the scientific community. Throughout the year, ships routinely collected and transmitted weather data. Similarly, as NOAA participants in the Integrated Global Ocean Station System (IGOSS) service program, XBT observations were taken and either radioed or submitted in log form via mail. In addition, particulate and radionuclide samples were taken in cooperation with the Atomic Energy Commission, sediment samples were obtained for the Smithsonian Institution and observations were made of marine mammals

Single liner shipping service design

DEFF Research Database (Denmark)

Plum, Christian Edinger Munk; Pisinger, David; Salazar-González, Juan-José

2014-01-01

The design of container shipping networks is an important logistics problem, involving assets and operational costs measured in billions of dollars. To guide the optimal deployment of the ships, a single vessel round trip is considered by minimizing operational costs and flowing the best paying...

Auxiliary facilities on nuclear ship 'MUTSU'

International Nuclear Information System (INIS)

Tsujimura, Shotaro; Takigami, Yoshio.

1989-01-01

The nuclear ship 'MUTSU' has been moored at SEKINEHAMA, MUTU City in AOMORI Prefecture and several tests and works are being carried out on the ship. The construction of the auxiliary facilities for these works on the ship was completed in safety in August 1988. After that the facilities have fulfilled their function. The outlines of design, fabrication and construction of the facilities are described in this paper. (author)

Production Balance of Ship Erection

Institute of Scientific and Technical Information of China (English)

JIANG Ru-hong; TAN Jia-hua; LIU Cun-gen

2008-01-01

A network plan model of ship erection was established based on the network planning technologyand the work-package breakdown system. The load-oriented production control method was introduced to buildup a throughput diagram model thus it is possible to describe the ship erection process numerically. Based onthe digitaiized models some cases of production balance of ship erection were studied and three balance indexeswere put forward, they are the load balance rate, the input manpower balance rate and the maximum gantrycrane operating times. Such an analytic method based on the balance evaluation is the important foundationfor digitization and intelligentization of shipyard production management.

Extreme Wave-Induced Oscillation in Paradip Port Under the Resonance Conditions

Science.gov (United States)

Kumar, Prashant; Gulshan

2017-12-01

A mathematical model is constructed to analyze the long wave-induced oscillation in Paradip Port, Odisha, India under the resonance conditions to avert any extreme wave hazards. Boundary element method (BEM) with corner contribution is utilized to solve the Helmholtz equation under the partial reflection boundary conditions. Furthermore, convergence analysis is also performed for the boundary element scheme with uniform and non-uniform discretization of the boundary. The numerical scheme is also validated with analytic approximation and existing studies based on harbor resonance. Then, the amplification factor is estimated at six key record stations in the Paradip Port with multidirectional incident waves and resonance modes are also estimated at the boundary of the port. Ocean surface wave field is predicted in the interior of Paradip Port for the different directional incident wave at various resonance modes. Moreover, the safe locations in the port have been identified for loading and unloading of moored ship with different resonance modes and directional incident waves.

MASTER OF THE SHIP, MANAGER AND INSTRUCTOR

Directory of Open Access Journals (Sweden)

Florin IORDANOAIA

2010-01-01

Full Text Available The master of the ship is the person on the board who has the qualification and the necessary certificate of competency for running a maritime transport ship. He is the one who takes the ship into administration from the ship-owner, he is the only leader, the legal and direct chief of the entire crew, being invested with authority upon all the members of the crew. The master fulfils the attributes and displays his activity according to the legal laws of his flag, of the marine regulations and of the international conventions. In all the relationships which he establishes with physical or juridical people, the master represents the ship-owner, in a double condition, as an officer and as a commercial manager. In this paper, it is analysed the situation of the ship masters, the relationships which these masters have with the crew and the problems which appear during their voyage. At the end of the paper there are proposed measures to increase the quality of the training of the ship masters, to solve the situations connected with the members of the crew.

Ship dynamics for maritime ISAR imaging.

Energy Technology Data Exchange (ETDEWEB)

Doerry, Armin Walter

2008-02-01

Demand is increasing for imaging ships at sea. Conventional SAR fails because the ships are usually in motion, both with a forward velocity, and other linear and angular motions that accompany sea travel. Because the target itself is moving, this becomes an Inverse- SAR, or ISAR problem. Developing useful ISAR techniques and algorithms is considerably aided by first understanding the nature and characteristics of ship motion. Consequently, a brief study of some principles of naval architecture sheds useful light on this problem. We attempt to do so here. Ship motions are analyzed for their impact on range-Doppler imaging using Inverse Synthetic Aperture Radar (ISAR). A framework for analysis is developed, and limitations of simple ISAR systems are discussed.

Communication from the Radioactive Shipping Service

CERN Multimedia

DDGS Unit

2011-01-01

The radioactive materials Import/Export service reminds you that all movements of potentially radioactive material must be declared in advance. For exports, shipping requests must be made via the EDH request form, ticking the box “radioactive material”. For imports, an electronic form must be completed before the arrival of the material. Requests which do not comply with the above procedure and any unauthorized imports of radioactive material will be refused.The same applies to imports/exports of radioactive sources. All necessary information is given in the web site: http://cern.ch/service-rp-shipping Yann Donjoux / Radioactive Shipping Service Phone: +41 22 767.31.71 Fax: +41 22 766.92.00 Email: service-rp-shipping@cern.ch

Nuclear powered freight ships - safe and reliable

International Nuclear Information System (INIS)

Schafstall, H.C.

1978-12-01

The five nuclear-powered ships built in the world so far have entered over 100 ports in 14 countries about 1000 times in 15 years, during which there were no accidents endangering the safety of a ship. However, for the expansion of freight shipping with nuclear power, comprehensive international regulations for safety requirements, responsibility etc., are necessary. Although the NEA/IAEO symposium excluded economic questions on the safety of nuclear powered ships, the trends regarding further development in individual countries became clear

Method for calculating wave resistance in a catamaran by using a simple panel method; Kanbenna panel ho ni yoru katamaran no zoha teiko keisanho

Energy Technology Data Exchange (ETDEWEB)

Kataoka, K [Kyushu University, Fukuoka (Japan). Faculty of Engineering

1997-10-01

This paper describes a method for calculating wave resistance in a catamaran by using a simple panel method. Two Wigley models were put side by side to make a catamaran, speccular images were taken on a face symmetrical in the left and right sides, and only one side (the demi-hull) was used as a region to be calculated. Considering blow-out onto the demi-hull surface and still water surface, a model was constituted, in which discrete vortices were distributed on the demi-hull camber to flow the vortices out to an infinitely distance place from the stern. A free surface condition according to double model linearization by Dawson was derived for this model in terms of numerical analysis. The Kutta`s condition is incorporated when SQCM is used concurrently with the Rankine source method, but not incorporated when not used. Calculations were performed on both conditions. Wave resistance was derived by using pressure integral on the hull surface. It is better to consider the Kutta`s condition when the distance between the demi-hulls is small. However, if the distance is large, or speed is great for the boat length resulting in less interference between the demi-hulls, there is very little difference due to the Kutta`s condition. Difference in the wave shapes causes how waves are made to vary. 11 refs., 8 figs.

Structural health monitoring for ship structures

Energy Technology Data Exchange (ETDEWEB)

Farrar, Charles [Los Alamos National Laboratory; Park, Gyuhae [Los Alamos National Laboratory; Angel, Marian [Los Alamos National Laboratory; Bement, Matthew [Los Alamos National Laboratory; Salvino, Liming [NSWC, CADEROCK

2009-01-01

Currently the Office of Naval Research is supporting the development of structural health monitoring (SHM) technology for U.S. Navy ship structures. This application is particularly challenging because of the physical size of these structures, the widely varying and often extreme operational and environmental conditions associated with these ships missions, lack of data from known damage conditions, limited sensing that was not designed specifically for SHM, and the management of the vast amounts of data that can be collected during a mission. This paper will first define a statistical pattern recognition paradigm for SHM by describing the four steps of (1) Operational Evaluation, (2) Data Acquisition, (3) Feature Extraction, and (4) Statistical Classification of Features as they apply to ship structures. Note that inherent in the last three steps of this process are additional tasks of data cleansing, compression, normalization and fusion. The presentation will discuss ship structure SHM challenges in the context of applying various SHM approaches to sea trials data measured on an aluminum multi-hull high-speed ship, the HSV-2 Swift. To conclude, the paper will discuss several outstanding issues that need to be addressed before SHM can make the transition from a research topic to actual field applications on ship structures and suggest approaches for addressing these issues.

Report of Nuclear Powered Ship Council

International Nuclear Information System (INIS)

1982-01-01

From the forecast of energy balance in the world to 21st century, the diversification of energy supply and the technical development enabling it are necessary in Japan. The stable supply of marine fuel is important to maintain and develop the national life. At present, as the marine fuel substituting for petroleum, atomic energy is at the position nearest to practical use. In advanced countries, the basic technology required for the practical use of nuclear-powered merchant ships seems to have been established, but Japan is about 10 years behind them due to the delay of the Mutsu project. In order to maintain and improve the technical level of shipbuilders, the independent technology related to nuclear-powered ships must be established in Japan. In the economical examination of nuclear-powered ships, ice breakers and ice breaking tankers are advantageous, but in other types of ships, a number of conditions must be satisfied to be economical. The Mutsu must be operated to collect the data and experience, and the project of an improved marine prototype reactor must be decided. Also a demonstration ship must be built. The standards for the design, construction and operation of nuclear-powered ships and the public acceptance are necessary. (Kako, I.)

Ship exhaust gas plume cooling

NARCIS (Netherlands)

Schleijpen, H.M.A.; Neele, P.P.

2004-01-01

The exhaust gas plume is an important and sometimes dominating contributor to the infrared signature of ships. Suppression of the infrared ship signatures has been studied by TNO for the Royal Netherlands Navy over considerable time. This study deals with the suppression effects, which can be

Slamming Simulations in a Conditional Wave

DEFF Research Database (Denmark)

Seng, Sopheak; Jensen, Jørgen Juncher

2012-01-01

A study of slamming events in conditional waves is presented in this paper. The ship is sailing in head sea and the motion is solved for under the assumption of rigid body motion constrained to two degree-of-freedom i.e. heave and pitch. Based on a time domain non-linear strip theory most probable...... surface NS/VOF CFD simulations under the same wave conditions. In moderate seas and no occurrence of slamming the structural responses predicted by the methods agree well. When slamming occurs the strip theory overpredicts VBM but the peak values of VBM occurs at approximately the same time as predicted...... by the CFD method implying the possibility to use the more accurate CFD results to improve the estimation of slamming loads in the strip theory through a rational correction coefficient....

Extreme value predictions and critical wave episodes for marine structures by FORM

DEFF Research Database (Denmark)

Jensen, Jørgen Juncher

2007-01-01

The aim of the present paper is to advocate for a very effective stochastic procedure, based on the First Order Reliability Method (FORM), for extreme value predictions related to wave induced loads. Three different applications will be illustrated. The first deals with a jack-up rig where second...... order stochastic waves are included in the analysis. The second application is parametric roll motions of ships. Finally, the motion of a TLP floating foundation for an offshore wind turbine is analysed taking into account large motions....

Extreme value predictions and critical wave episodes for marine structures by FORM

DEFF Research Database (Denmark)

Jensen, Jørgen Juncher

2008-01-01

The aim of the present paper is to advocate for a very effective stochastic procedure, based on the First Order Reliability Method (FORM), for extreme value predictions related to wave induced loads. Three different applications will be illustrated. The first deals with a jack-up rig where second...... order stochastic waves are included in the analysis. The second application is parametric roll motions of ships. Finally, the motion of a TLP floating foundation for an offshore wind turbine is analysed taking into account large motions....

Note from the radioprotection group's shipping service

CERN Multimedia

2006-01-01

Le service SHIPPING du groupe de radioprotection souhaite vous rappeler qu'avant toute expédition de matériel susceptible d'être radioactif, une demande de transport doit être établie par EDH en cochant la case appropriée (danger radioactif). Merci de bien vouloir prendre note des informations figurant dans le site Web: http://cern.ch/service-rp-shipping Toute demande non conforme ne sera pas prise en compte. Radioactive Shipping Service http://cern.ch/service-rp-shippingTél: 73171Fax: 69200

Ships going slow in reducing their NOx emissions: changes in 2005–2012 ship exhaust inferred from satellite measurements over Europe

International Nuclear Information System (INIS)

Boersma, K Folkert; Vinken, Geert C M; Tournadre, Jean

2015-01-01

We address the lack of temporal information on ship emissions, and report on rapid short-term variations of satellite-derived ship NO x emissions between 2005 and 2012 over European seas. Our inversion is based on OMI observed tropospheric NO 2 columns and GEOS-Chem simulations. Average European ship NO x emissions increased by ∼15% from 2005 to 2008. This increase was followed by a reduction of ∼12% in 2009, a direct result of the global economic downturn in 2008–2009, and steady emissions from 2009 to 2012. Observations of ship passages through the Suez Canal and satellite altimeter derived ship densities suggests that ships in the Mediterranean Sea have reduced their speed by more than 30% since 2008. This reduction in ship speed is accompanied by a persistent 45% reduction of average, per ship NO x emission factors. Our results indicate that the practice of ‘slow steaming’, i.e. the lowering of vessel speed to reduce fuel consumption, has indeed been implemented since 2008, and can be detected from space. In spite of the implementation of slow steaming, one in seven of all NO x molecules emitted in Europe in 2012 originated from the shipping sector, up from one in nine in 2005. The growing share of the shipping contributions to the overall European NO x emissions suggests a need for the shipping sector to implement additional measures to reduce pollutant emissions at rates that are achieved by the road transport and energy producing sectors in Europe. (letter)

Wallops Ship Surveillance System

Science.gov (United States)

Smith, Donna C.

2011-01-01

Approved as a Wallops control center backup system, the Wallops Ship Surveillance Software is a day-of-launch risk analysis tool for spaceport activities. The system calculates impact probabilities and displays ship locations relative to boundary lines. It enables rapid analysis of possible flight paths to preclude the need to cancel launches and allow execution of launches in a timely manner. Its design is based on low-cost, large-customer- base elements including personal computers, the Windows operating system, C/C++ object-oriented software, and network interfaces. In conformance with the NASA software safety standard, the system is designed to ensure that it does not falsely report a safe-for-launch condition. To improve the current ship surveillance method, the system is designed to prevent delay of launch under a safe-for-launch condition. A single workstation is designated the controller of the official ship information and the official risk analysis. Copies of this information are shared with other networked workstations. The program design is divided into five subsystems areas: 1. Communication Link -- threads that control the networking of workstations; 2. Contact List -- a thread that controls a list of protected item (ocean vessel) information; 3. Hazard List -- threads that control a list of hazardous item (debris) information and associated risk calculation information; 4. Display -- threads that control operator inputs and screen display outputs; and 5. Archive -- a thread that controls archive file read and write access. Currently, most of the hazard list thread and parts of other threads are being reused as part of a new ship surveillance system, under the SureTrak project.

Detection of Parametric Roll Resonance on Ships from Indication of Nonlinear Energy Flow

DEFF Research Database (Denmark)

Galeazzi, Roberto; Blanke, Mogens; Poulsen, Niels Kjølstad

2009-01-01

The detection of the onset of parametric roll resonance on ships is of a central importance in order to activate specific control strategies able to counteract the large roll motion. One of the main priorities is to have detectors with a small detection time, such that warnings can be issued when...... the roll oscillations are about 5◦. This paper proposes two different detection approaches: the first one based on sinusoidal detection in white gaussian noise; the second one utilizes an energy flow indicator in order to catch the onset of parametric roll based upon the transfer of energy from heave...... and pitch to roll. Both detectors have been validated against experimental data of a scale model of a container vessel excited with both regular and irregular waves. The detector based on the energy flow indicator proved to be very robust to different scenarios (regular/irregular waves) since it does...

29 CFR 1915.164 - Ship's propulsion machinery.

Science.gov (United States)

2010-07-01

... 29 Labor 7 2010-07-01 2010-07-01 false Ship's propulsion machinery. 1915.164 Section 1915.164 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED) OCCUPATIONAL SAFETY AND HEALTH STANDARDS FOR SHIPYARD EMPLOYMENT Ship's Machinery and Piping Systems § 1915.164 Ship's...

47 CFR 80.59 - Compulsory ship inspections.

Science.gov (United States)

2010-10-01

... 47 Telecommunication 5 2010-10-01 2010-10-01 false Compulsory ship inspections. 80.59 Section 80... STATIONS IN THE MARITIME SERVICES Applications and Licenses § 80.59 Compulsory ship inspections. (a) Inspection of ships subject to the Communications Act or the Safety Convention. (1) The FCC will not normally...

Internationalisation Within Liner Shipping

DEFF Research Database (Denmark)

Prockl, Günter; Kinra, Aseem; Kotzab, Herbert

2018-01-01

, the degree of internationalisation, measured on the basis of sea-oriented operations, differs from that measured according to land-oriented front-end marketing and sales activities. The purpose of this study is to further examine the internationalisation patterns of shipping lines. An examination...... of the front-end activities and the structures of leading container-shipping companies is conducted. The sales office networks of the sector’s 20 largest companies worldwide (by twenty-foot equivalent unit capacity) are analysed as key indicators. The numbers of sales offices are measured by analysing...... the websites of the sample (20 companies), as well as annual reports and other publicly available data sources. The findings show that not all shipping companies are international, by virtue of the industry. While it is difficult to observe differences in the overall patterns of the sales networks at a macro...

Development of Tsunami Numerical Model Considering the Disaster Debris such as Cars, Ships and Collapsed Buildings

Science.gov (United States)

Kozono, Y.; Takahashi, T.; Sakuraba, M.; Nojima, K.

2016-12-01

A lot of debris by tsunami, such as cars, ships and collapsed buildings were generated in the 2011 Tohoku tsunami. It is useful for rescue and recovery after tsunami disaster to predict the amount and final position of disaster debris. The transport form of disaster debris varies as drifting, rolling and sliding. These transport forms need to be considered comprehensively in tsunami simulation. In this study, we focused on the following three points. Firstly, the numerical model considering various transport forms of disaster debris was developed. The proposed numerical model was compared with the hydraulic experiment by Okubo et al. (2004) in order to verify transport on the bottom surface such as rolling and sliding. Secondly, a numerical experiment considering transporting on the bottom surface and drifting was studied. Finally, the numerical model was applied for Kesennuma city where serious damage occurred by the 2011 Tohoku tsunami. In this model, the influence of disaster debris was considered as tsunami flow energy loss. The hydraulic experiments conducted in a water tank which was 10 m long by 30 cm wide. The gate confined water in a storage tank, and acted as a wave generator. A slope was set at downstream section. The initial position of a block (width: 3.2 cm, density: 1.55 g/cm3) assuming the disaster debris was placed in front of the slope. The proposed numerical model simulated well the maximum transport distance and the final stop position of the block. In the second numerical experiment, the conditions were the same as the hydraulic experiment, except for the density of the block. The density was set to various values (from 0.30 to 4.20 g/cm3). This model was able to estimate various transport forms including drifting and sliding. In the numerical simulation of the 2011 Tohoku tsunami, the condition of buildings was modeled as follows: (i)the resistance on the bottom using Manning roughness coefficient (conventional method), and (ii)structure of

MASTER OF THE SHIP, MANAGER AND INSTRUCTOR

OpenAIRE

Florin IORDANOAIA

2010-01-01

The master of the ship is the person on the board who has the qualification and the necessary certificate of competency for running a maritime transport ship. He is the one who takes the ship into administration from the ship-owner, he is the only leader, the legal and direct chief of the entire crew, being invested with authority upon all the members of the crew. The master fulfils the attributes and displays his activity according to the legal laws of his flag, of the marine regulations and...

Allocation of ESS by interval optimization method considering impact of ship swinging on hybrid PV/diesel ship power system

International Nuclear Information System (INIS)

Wen, Shuli; Lan, Hai; Hong, Ying-Yi; Yu, David C.; Zhang, Lijun; Cheng, Peng

2016-01-01

Highlights: • An uncertainty model of PV generation on board is developed based on the experiments. • The moving and swinging of the ship are considered in the optimal ESS sizing problem. • Optimal sizing of ESS in a hybrid PV/diesel/ESS ship power system is gained by the interval optimization method. • Different cases were studied to show the significance of the proposed method considering the swinging effects on the cost. - Abstract: Owing to low efficiency of traditional ships and the serious environmental pollution that they cause, the use of solar energy and an energy storage system (ESS) in a ship’s power system is increasingly attracting attention. However, the swinging of a ship raises crucial challenges in designing an optimal system for a large oil tanker ship, which are associated with uncertainties in solar energy. In this study, a series of experiments are performed to investigate the characteristics of a photovoltaic (PV) system on a moving ship. Based on the experimental results, an interval uncertainty model of on-board PV generation is established, which considers the effect of the swinging of the ship. Due to the power balance equations, the outputs of the diesel generator and the ESS on a large oil tanker are also modeled using interval variables. An interval optimization method is developed to determine the optimal size of the ESS in this hybrid ship power system to reduce the fuel cost, capital cost of the ESS, and emissions of greenhouse gases. Variations of the ship load are analyzed using a new method, taking five operating conditions into account. Several cases are compared in detail to demonstrate the effectiveness of the proposed algorithm.

Developments in the design of the PS Frog Mk 5 wave energy converter

Energy Technology Data Exchange (ETDEWEB)

McCabe, A.P.; Bradshaw, A.; Meadowcroft, J.A.C.; Aggidis, G. [Department of Engineering, Lancaster University Renewable Energy Group, Lancaster LA1 4YR (United Kingdom)

2006-02-01

This paper describes one of the innovative wave energy converters under development by the Lancaster University Renewable Energy Group. An offshore point-absorber wave energy converter, PS Frog Mk 5 consists of a large buoyant paddle with an integral ballasted 'handle' hanging below it. The waves act on the blade of the paddle and the ballast beneath provides the necessary reaction. When the WEC is pitching, power is extracted by partially resisting the sliding of a power-take-off mass, which moves in guides above sea level. Totally enclosed in a steel hull, with no external moving parts, PS Frog Mk. 5 is at least as robust as a ship and the survivability of the device is currently under investigation, though such work is beyond the scope of this paper. Such a device could be very economic in terms of power output per unit of capital cost. New inventive steps with experimental results and computer studies have led to promising improvements to the hull shape. The WEC is maintained in a resonant state by the use of special means to maintain a high dynamic magnifier in irregular seas. A robust feedback control system has been developed to ensure stability and maintain efficient power take-off. Some of these developments are described and illustrated with the results of computer simulations that show power outputs and device motion over a range of conditions. It is shown that useful advances have been made, with the power capture bordering on 2MW in an increasing proportion of sea states. (author)

Safety analysis report for packaging (SARP) of the Oak Ridge National Laboratory. TRU curium shipping container

International Nuclear Information System (INIS)

Box, W.D.; Klima, B.B.; Seagren, R.D.; Shappert, L.B.; Aramayo, G.A.

1980-06-01

An analytical evaluation of the Oak Ridge National Laboratory Transuranium (TRU) Curium Shipping Container was made to demonstrate its compliance with the regulations governing offsite shipment of packages containing radioactive material. The evaluation encompassed five primary categories: structural integrity, thermal resistance, radiation shielding, nuclear criticality safety, and quality assurance. The results of the evaluation show that the container complies with the applicable regulations

Arctic shipping emissions inventories and future scenarios

Directory of Open Access Journals (Sweden)

J. J. Corbett

2010-10-01

Full Text Available This paper presents 5 km×5 km Arctic emissions inventories of important greenhouse gases, black carbon and other pollutants under existing and future (2050 scenarios that account for growth of shipping in the region, potential diversion traffic through emerging routes, and possible emissions control measures. These high-resolution, geospatial emissions inventories for shipping can be used to evaluate Arctic climate sensitivity to black carbon (a short-lived climate forcing pollutant especially effective in accelerating the melting of ice and snow, aerosols, and gaseous emissions including carbon dioxide. We quantify ship emissions scenarios which are expected to increase as declining sea ice coverage due to climate change allows for increased shipping activity in the Arctic. A first-order calculation of global warming potential due to 2030 emissions in the high-growth scenario suggests that short-lived forcing of ~4.5 gigagrams of black carbon from Arctic shipping may increase global warming potential due to Arctic ships' CO₂ emissions (~42 000 gigagrams by some 17% to 78%. The paper also presents maximum feasible reduction scenarios for black carbon in particular. These emissions reduction scenarios will enable scientists and policymakers to evaluate the efficacy and benefits of technological controls for black carbon, and other pollutants from ships.

Improving the competitiveness of green ship recycling

NARCIS (Netherlands)

Jain, K.P.

2017-01-01

The end of life of a ship is determined by its owner on the basis of various commercial and technical factors. Once decided to scrap a ship, almost all end-of-life (EOL) ships are sold to recycling yards for dismantling; except for a few which are converted into museums, hotels, storage, and

Achieving Energy Efficient Ship Operations Under Third Party Management

DEFF Research Database (Denmark)

Taudal Poulsen, René; Sornn-Friese, Henrik

2015-01-01

Profitable energy saving measures are often not fully implemented in shipping, causing energy efficiency gaps. The paper identifies energy efficiency gaps in ship operations, and explores their causes. Lack of information on energy efficiency, lack of energy training at sea and onshore and lack...... of time to produce and provide reliable energy efficiency information cause energy efficiency gaps. The paper brings together the energy efficiency and ship management literatures, demonstrating how ship management models influence energy efficiency in ship operations. Achieving energy efficiency in ship...

Analysis of Ship Groundings on Soft Sea Beds

DEFF Research Database (Denmark)

Simonsen, Bo Cerup; Pedersen, Preben Terndrup

1997-01-01

it influences the ship heave and pitch motions as well as the friction between the ship and the soil.In this paper a rational calculation model is presented for the sea bed soil reaction forces on the ship bottom. The model is based on the assumption that the penetration of the ship bow generates a flow of pore......The consequences associated with ships running aground depend very much on the soil characteristics of the sea bed and the geometrical shape of the ship bow. The penetration into the sea bed depends on these factors and the penetration is an important factor for the ship motion because...... by the theory of frictional soils in rupture. Frictional stresses on the bow surface are assumed to be related to the normal pressure by a simple Coulumb relation. The total soil reaction as a function of velocity and penetration is found by integration of normal pressure and frictional stresses over...

The Navy’s Coupled Atmosphere-Ocean-Wave Prediction System

Science.gov (United States)

2011-04-15

7300 Security, Code 1226 Office of Counsel,Code 1008.3 ADOR/Director NCST E. R. Franchi , 7000 Public Affairs (Unclassified/ Unlimited Only...Office as both a global model and relocatable regional model. The wave components of the system are run operationally at production centers at both...utilizes meteorological observations including radiosondes, satellite data, ship reports, and ocean observations with time-dependent global

Optimization of ship inner shell to improve the safety of seagoing transport ship

Directory of Open Access Journals (Sweden)

Yan-Yun YU

2013-09-01

Full Text Available A practical Ship Inner Shell Optimization Method (SISOM, the purpose of which is to improve the safety of the seagoing transport ship by decreasing the maximum Still Water Bending Moment (SWBM of the hull girder under all typical loading conditions, is presented in this paper. The objective of SISOM is to make the maximum SWBM minimum, and the section areas of the inner shell are taken as optimization variables. The main requirements of the ship performances, such as cargo hold capacity, propeller and rudder immersion, bridge visibility, damage stability and prevention of pollution etc., are taken as constraints. The penalty function method is used in SISOM to change the above nonlinear constraint problem into an unconstrained one, which is then solved by applying the steepest descent method. After optimization, the optimal section area distribution of the inner shell is obtained, and the shape of inner shell is adjusted according to the optimal section area. SISOM is applied to a product oil tanker and a bulk carrier, and the maximum SWBM of the two ships is significantly decreased by changing the shape of inner shell plate slightly. The two examples prove that SISOM is highly efficient and valuable to engineering practice.

Seafloor Geodesy usi­ng Wave Gliders to study Earthquake and Tsunami Hazards at Subduction Zones

Science.gov (United States)

Sathiakumar, S.; Barbot, S.; Hill, E.; Peng, D.; Zerucha, J.; Suhaimee, S.; Chia, G.; Salamena, G. G.; Syahailatua, A.

2016-12-01

Land-based GNSS networks are now in place to monitor most subduction zones of the world. These provide valuable information about the amount of­ geodetic strain accumulated in the region, which in turn gives insight into the seismic potential. However, it is usually impossible to resolve activity on the megathrust near the trench using land-based GNSS data alone, given typical signal-to-noise ratios. Ship-based seafloor geodesy is being used today to fill this observation gap. However, surveys using ships are very expensive, tedious and impractical due to the large areas to be covered. Instead of discrete missions using ships, continuous monitoring of the seafloor using autonomous marine robots would aid in understanding the tectonic setting of the seafloor better at a potentially lower cost, as well as help in designing better warning systems. Thus, we are developing seafloor geodesy capabilities using Wave Gliders, a new class of wave-propelled, persistent marine autonomous vehicle using a combination of acoustic and GNSS technologies. We use GNSS/INS to position the platform, and acoustic ranging to locate the seafloor. The GNSS/INS system to be integrated with the Wave Gliders has stringent requirements of low power, light weight, and high accuracy. All these factors are equally important due to limited power and space in the Wave Gliders and the need for highly accurate and precise measurements. With this hardware setup, a limiting factor is the accuracy of measurement of the sound velocity in the water column. We plan to obtain precise positioning of seafloor by exploring a measurement setup that minimizes uncertainties in sound velocity. This will be achieved by making fine-resolution measurements of the two-way travel time of the acoustic waves underwater using the Wave Gliders, and performing statistical signal processing on this data to obtain more reliable sound velocity measurement. This enhanced seafloor geodetic technique using Wave Gliders should

An Adaptive Ship Detection Scheme for Spaceborne SAR Imagery

Directory of Open Access Journals (Sweden)

Xiangguang Leng

2016-08-01

Full Text Available With the rapid development of spaceborne synthetic aperture radar (SAR and the increasing need of ship detection, research on adaptive ship detection in spaceborne SAR imagery is of great importance. Focusing on practical problems of ship detection, this paper presents a highly adaptive ship detection scheme for spaceborne SAR imagery. It is able to process a wide range of sensors, imaging modes and resolutions. Two main stages are identified in this paper, namely: ship candidate detection and ship discrimination. Firstly, this paper proposes an adaptive land masking method using ship size and pixel size. Secondly, taking into account the imaging mode, incidence angle, and polarization channel of SAR imagery, it implements adaptive ship candidate detection in spaceborne SAR imagery by applying different strategies to different resolution SAR images. Finally, aiming at different types of typical false alarms, this paper proposes a comprehensive ship discrimination method in spaceborne SAR imagery based on confidence level and complexity analysis. Experimental results based on RADARSAT-1, RADARSAT-2, TerraSAR-X, RS-1, and RS-3 images demonstrate that the adaptive scheme proposed in this paper is able to detect ship targets in a fast, efficient and robust way.