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REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
> Journal Vol & Issue
Journal of Ocean Engineering and Technology
Journal Basic Information
Journal DOI :
Korean Society of Ocean Engineers
Editor in Chief :
Volume & Issues
Volume 13, Issue 4 - Nov 1999
Volume 13, Issue 3 - Aug 1999
Volume 13, Issue 3B - Aug 1999
Volume 13, Issue 2 - May 1999
Volume 13, Issue 1 - Feb 1999
Volume 13, Issue 4 - 00 1999
Selecting the target year
A Study on the Selective Use of Higher Order Elements
Kim, Jin-Whan ;
Journal of Ocean Engineering and Technology, volume 13, issue 4, 1999, Pages 1~9
A Method for Vibration and Sensitivity Analysis of Structure Systems with Non-linear Characteristics
Moon, Byung-Young ; Kim, Sa-Soo ; Iwatsubo, Takuzo ;
Journal of Ocean Engineering and Technology, volume 13, issue 4, 1999, Pages 10~18
A Method for Vibration and Sensitivity Analysis of Structure Systems with Non-linear Characteristics
Mun, Byeong Yeong ; Kim, Sa Su ; Am, Dae Jang ;
Journal of Ocean Engineering and Technology, volume 13, issue 4, 1999, Pages 10~10
Hydroelastic Response Characteristics of a Very Large Offshore Structures of Somisubmersible Type in waves
Goo, Ja-Sam ; Kim, Kyung-Tae ; Hong, Bong-Ki ;
Journal of Ocean Engineering and Technology, volume 13, issue 4, 1999, Pages 19~27
To design a very large floating structure, such as a floating airport, we have to estimate the hydroelastic responses of a very large floating structure (VLFS) exactly. We developed the numerical method for estimating the hydroelastic responses of the VLFS. The developed numerical approach is based on a combination of the three-dimensional source distribution method, the wave interaction theory and the finite element method for structurally treating the space frame elements. The Numerical results of the hydroelastic responses and steady drift forces of a somisubmersible type offshore structure, which is supported by the 33(3 by 11) floating bodies, with various bending rigidities are illustrated.
The Experimental Study of Flux Improvement of Wet Underwater Arc Welding Electrode
Kim, Min-Nam ; Kang, Jung-Gun ;
Journal of Ocean Engineering and Technology, volume 13, issue 4, 1999, Pages 28~36
Wet underwater arc welding process is investigated by using experimentally developed flux coated underwater arc welding electrode and SS400 steel plate of 12mm thickness as base metal. Three kinds of different flux covered wet arc welding electrode of 4mm diameter(BK-01, BK-02, BK-03) are individually developed, and one of the improved underwater welding electrode (BK-03) may be put to practical use for underwater wet arc welding process. The results obtained from this experimental study are as follows : 1. Arc stability of developed underwater wet welding electrode is better than that of the domestic covered arc welding electrode. 2. Workability of welding electrode, remove ability of slag and bead appearances using improved underwater wet welding electrode are remarkably better than that of others. 3. Heat affected zone of test specimen welded in the underwater gets to become a lot smaller than that of test specimen welded in the air, and the maximum hardness of heat affect zone of developed underwater wet welding electrode is lower to that of domestic arc welding electrode.
Effect of Fabricating Temperature on Hardness Characteristics of
Lee, Sang-Pill ; Yoon, Han-Ki ;
Journal of Ocean Engineering and Technology, volume 13, issue 4, 1999, Pages 37~44
Hardness characteristics and microstructures of
laminate composites were evaluated from the variation of fabricating conditions such as preparation temperature, applied pressure and pressure holding time.
laminate composites composed of
powder and Nb sheets were fabricated by the hot press. From experimental results, it was found that the lamination from Nb sheet and
powder was an excellent strategy to improve hardness characteristics of monolithic
. However, interfacial reaction products like(Nb, Mo)
formed at the interface of
and increased with fabricating temperature.
Optimal Test Condition by Ultrasonic Simulation
Huh, Sun-Chul ; Park, Young-Chul ; Boo, Myung-Hwan ; Kang, Jung-Ho ;
Journal of Ocean Engineering and Technology, volume 13, issue 4, 1999, Pages 45~54
Non destructive test is applied to revise mechanical strength and assume material strength or defect of material, equipment and structure, instead of fracture test. Especially, ultrasonic test has the characteristics such as an excellent permeability high-sensitiveness to fine defect and an almost exact measurement for position, size and direction of inner defect which differ from other non destructive tests. In this study, the program is developed to evaluate optimal testing condition, to distinguish obstacle echo and defect position. This program on the basic of Ray-Tracing model shows generation and processing of ultrasonic pulse. The simulation is compared with testing in the 3 cases of an oblique angle transducer like
. The test result for all conditions is well compared with simulation result when relative not is within
. And the course of several echos is simply assumed through simulation.
A Study on Fatigue Damage Modelling in Cold Rolled Steel using X-ray Residual Stress
Cho, Seok-Swoo ; Joo, Won-Sik ;
Journal of Ocean Engineering and Technology, volume 13, issue 4, 1999, Pages 55~62
Cold rolled steel has much plastic strain in the material surface produced by manufacturing process. The strain causes the variation of surface residual stress, in which influences the fatigue behavior under repeated loading. As experimental results, it was confirmed that the behavior of residual stress
, with cycle N consisted of three stages except stress amplitude near fatigue limit in SPCC steel. On the first stage compressive residual stress decreased rapidly, on the second stage gradually, and on the last stage slightly. The relation between
, and log N appeared linear behavior except the early part of cycle ratio
. The average gradient of
, with respect to log N seemed to take a constant value without initial cycle ratio. On the other hand, the
line was regressed by the first-order polynomial equation on
diagram. Therefore, this study showed that both the gradient of
, with respect to log N and the
line was useful in predicting the cycle ratio
Effect of the Moisture Environment on the Mechanical Properties of Carbon Fiber Laminates
Kim, Won-Keun ; Moon, Chang-Kwon ;
Journal of Ocean Engineering and Technology, volume 13, issue 4, 1999, Pages 63~74
This study has been investigated about the influence of moisture environment on the mechanical properties in the carbon fiber cross laminates. And it has been also investigated the effect of unit ply thickness of the carbon fiber cross laminates on the mechanical properties in distilled water of
for a certain period of time. As a results, it was found that the weight gain of water was increased with the immersion time and the bending strength and fracture toughness were decreased with the weight gain of water. And it was also shown that the bending strength and fracture toughness were decreased with the increasing of the unit ply thickness of carbon fiber cross laminates through the immersion time.
Design of Forming Rolls using Finite Element Analysis
Kim, Kwang-Heui ;
Journal of Ocean Engineering and Technology, volume 13, issue 4, 1999, Pages 75~81
Roll forming process is simulated with a commercial FEM code LS-DYNA. The rolls are treated as rigid bodies rotating with a constant angular velocity. The strip and the rolls are modeled with 4-node plate elements. It is assumed that the nodes along the front end of the strip move along paths given by sine functions. It is found that the analysis can be applied to the optimal design of forming rolls. With these analyses, it is expected that forming defects can be avoided and process development efforts can be reduced.
Collapse Analysis for Deep Sea Pressure Vessel
Shin, Jang-Ryong ; Woo, Jong-Sik ;
Journal of Ocean Engineering and Technology, volume 13, issue 4, 1999, Pages 82~97
A deep sea vehicle must be designed to ensure its safety under ultra-high pressure circumstances. If a pressure housing of a deepsea vehicle is collapsed by ultra-high pressure, the deepsea vehicle may be lost. The objective of this paper is to introduce a design collapse pressure for the deep sea pressure vessel which is composed of one cylinder and two hemispheres. Especially the collapse pressure of hemispherical shell with a hole at top is analyzed by a variational approach (weighted residual method). And for the purpose of design, the salty factor of collapse pressure is presented which is analyzed by interpolation method.
Optimization of Friction Welding for Crank Shaft Steels and Its Real Time AE Evaluation
Oh, Sae-Kyoo ; Choi, Hei-Young ; Kong, Yu-Sik ;
Journal of Ocean Engineering and Technology, volume 13, issue 4, 1999, Pages 98~104
The crank shafts need anti-corrosion materials. So STS 304 is the essential material to manufacture this shaft. However, it costs more to manufacture the shafts by using only STS 304 than welding of STS 304 to other carbon steels. And it has been difficult to weld this sort of dissimilar materials. They could be unstable in the quality by the conventional arc welding. And also they have a lot of technical problems in manufacturing. But by the friction welding technique, it will be able to be made without such problems. Then, this study aimed not only to develop the optimization of dissimilar friction welding of crank shafts steels of STS 304, SM35C, but also to develop the application technique of the acoustic emission to accomplish in-process real-time quality(such as tensile) evaluation during friction welding of the shafts by the AE technique.
Dissimilar Friction Welding for Pinion Gear and Its Real Time AE Evaluation
Oh, Sae-Kyoo ; Son, Deog-Soo ; Yang, Hyung-Tae ;
Journal of Ocean Engineering and Technology, volume 13, issue 4, 1999, Pages 105~111
This study aimed not only to develop the optimization of dissimilar friction welding of pinion gear of a motor vehicle steels of SCM415 and SMn443, but also to develop the application technique of the acoustic emission to accomplish an in-process real-time quality(such as strength and toughness) evaluation during friction welding of the pinion gear by the AE technique.
Creep Properties of Aircraft Gas Turbine Materials in relation to Heat Treatment
Kong, Yu-Sik ; Oh, Sae-Kyoo ; Park, No-Kwang ;
Journal of Ocean Engineering and Technology, volume 13, issue 4, 1999, Pages 112~117
In this paper, the creep properties and creep life prediction by Larson-Miller Parameter method for Udimet 720 to be used for aircraft gas turbine engines or other high temperature components were presented at the elevated temperatures of 538, 649 and
. It was confirmed experimentally and quantitatively that a creep life predictive equation at such various high temperatures was well derived by LMP.
Estimation of Maneuvering Mathematical Model by System Identification Techniques
Lee, Ho-Young ; Shin, Hyun-Kyoung ;
Journal of Ocean Engineering and Technology, volume 13, issue 4, 1999, Pages 118~123
The mathematical model used in the simulation of ship's maneuvering contains the hydrodynamic coefficients, which are usually evaluated based on PMM model tests in the towing tank and used to predict ship's maneuvering performance when applied to the proto-type ship. The proper mathematical model has to be developed to predict ship's maneuvering motions with hydrodynamic coefficients very well. The mathematical model for PMM model tests is analyzed with identification program and the hydrodynamic coefficients and maneuvering motions by system identification we compared with those obtained directly from PMM model tests and sea trial. The mathematical model for PMM model tests was established and the magnitudes of ship's maneuvering coefficients were determined. When the identified values of coefficients were used to simulate the maneuvers, a very good agreement was obtained between the numerically simulated motion responses and those obtained from PMM model tests.
Geostrophic Flows in a Container with a Vertical Plate
Choi, Yoon-Hwan ; Suh, Yong-Kweon ;
Journal of Ocean Engineering and Technology, volume 13, issue 4, 1999, Pages 124~131
In this paper, we show the numerical and experimental results of two-dimensional fluid motions inside a rectangular container with a vertical plate subjected to a background rotation added by a rotational oscillation. In the PIV experiment we apply a new algorithm, NTSS, to the velocity calculation. In the numerical computation, the linear Ekman-pumping model was used to take the bottom friction effect into account. It was found that it showed good agreement with the experimental results at low
Analysis of Motions and Wave Loads of Twin-Hull Ships in Waves
Goo, Ja-Sam ; Jo, Hyo-Jae ; Lee, Seung-Chul ;
Journal of Ocean Engineering and Technology, volume 13, issue 4, 1999, Pages 132~142
A three-dimensional linearised potential theory is presented for the prediction of motions and dynamic structural responses of twin-hull ships travelling with forward speed in regular waves. Comparisons between theoretical and experimental results are shown for the motion responses and lateral wave loads of an ASR(anti-submarine rescue) catamaran. In general, good agreement between theory and experiment is found except for some discrepancies that are believed to be caused by neglect of forward speed effects on free surface.
Basic Design of Multipurpose Fisheries Base for Marine Ranching Program
Kim, Hyeon-Ju ; Lee, Na-Ry ;
Journal of Ocean Engineering and Technology, volume 13, issue 4, 1999, Pages 143~150
Multipurpose fisheries base was conceptually designed to establish marine ranching system in the coastal waters around Tongyoung, southern sea of Korea. Fisheries base for marine ranching system has integrated various facilities which were required for the process of spawning, rearing, training, releasing, monitoring and catching functions. This base has five steel piles for supporting upper structure and systems. Four steel piles are surrounded by circular net pen made by steel wire, they have the function of the protection against fouling for pile and scouring for bottom soil as well as secondary rearing and short stocking. We can use the last pile to moor a ship and access to the base. Principal structure with steel piles is designed by optimization technique considering design external forces in the coastal waters of return period of 50 years. Design optimization Problem is formulated for this base. Optimal design of multipurpose fisheries base is numerically investigated by sequential quadratic programming method.
Flow Structure Prediction for a Square Harbour using Various Wall Boundary Conditions
Kang, Yun-Ho ;
Journal of Ocean Engineering and Technology, volume 13, issue 4, 1999, Pages 151~158
A model harbour with Plan scale of
is built on a tidal tank using a Froude relationship from a real harbour(
). Velocity components are measured by a ultrasonic velocity meter and flow structure is then predicted using a 2-D depth integrated hydrodynamic model. In the finite difference model implemented in this study, various wall boundary conditions, i.e. no-slip, free-slip, partial-slip and semi-slip are used to represent turbulent diffusion terms, e.g.
. These conditions are focused to investigate their influence on the flow structure along the wall and basin of the harbour with aspect ratio of unity, i.e. Length/Breadth. Numerical experiments are compared with the measurements and used to analyse flow patterns in the basin during tidal cycles. It is shown from the results that no-slip closed boundary condition is the most appropriate method with respect to the location of the eddy centre, although the condition underestimates velocity components along the wall.
A Fast Analysis on Floating Wave Energy Conversion System
Lee, Sang-Moo ; Kim, Seoung-Gun ;
Journal of Ocean Engineering and Technology, volume 13, issue 4, 1999, Pages 159~168
A Fast Analysis on Floating Wave Energy Conversion System
Lee, Sang Mu ; Kim, Seong Geun ;
Journal of Ocean Engineering and Technology, volume 13, issue 4, 1999, Pages 159~159
Hull Fairing by Modified Direct Curvature Manipulation Method
Yoon, Tae-Kyeong ; Kim, Dong-Joon ;
Journal of Ocean Engineering and Technology, volume 13, issue 4, 1999, Pages 169~173
In this paper some modifications for Lu's inverse method of fairing process are presented. The object function is changed and additional constraints for hull curve foiling is proposed. The newly introduced minimizing object function is the sum of the distances between the two curve's positions at the same parameter values instead of the sum of the distances between two vertices. The new one is better to represent the physical meaning of the object function, the smaller differences between two curves. In ship hull fairing the end tangent of curve has to be fined in some cases, so the additional constraint is considered to preserve the direction of end tangent. The sample results are shown.
Preliminary Hull Form Design Using Form Parameter Method and Neural Networks
Park, Won ; Shin, Sung-Chul ; Kim, Soo-Young ; Jang, Hyeon-Jae ;
Journal of Ocean Engineering and Technology, volume 13, issue 4, 1999, Pages 174~181
A form parameter method compounds the form parameters which define the hull geometric characteristics. This method can transform a hull form by changing the form parameters. The form parameter method is a hull define method without utilization of mother ships. However it is difficult to determine these form parameters. Thus, we are complemented the form parameter method using the neural networks. It is found that the form parameter method using the neural networks is efficient in hull form design by consideration of application examples.
Initial Robust Design of Deadweight 150,000 ton Bulk Carrier
Koh, Chang-Doo ; Kim, Soo-Young ;
Journal of Ocean Engineering and Technology, volume 13, issue 4, 1999, Pages 182~189
The robust design technology which can determine design variables getting best performance function with insensitivity to the environment noise, is an important method for improving the performance of products at low cost. Applying the robust design technology in ship design, Koh et al introduced the planing hull design. This paper reports the application this technology to a 150K bulk carrier which has many design variables and shows that the robust design technology is superior to optimization technique in practical use.