This paper present a review of trends in world energy demand and a close outlook over the offshore market, especially in deepwater developments. The market requirements, characteristics and risks involved in the contract type of offshore projects are explained, followed by the strategic approaches of Korean main yards along with, the HHI's development and introduction of innovative construction methodologies to be a competitive contractor.

The basic concept of an improved business and productivity for Small and Medium Sized Enterprizes, which makes use of an information portal, is to assure competitive power, increase the production quantity through the interchange of a company and the outside environment, and to build cooperation. To reduce the charge of the equipment, as well as to introduce and information program, it should build an information environment from inside the company by suing the information portal ASP(Application Service Provider). This portal is already built by the basic information infrastructure through the Internet.

The Objective of this research is to find the optimal design of the Noise Reduction Interference Model (NRIM) which is recently invented. Without optimization, the NRIM has been successful to reduce the urban noise induced by trains and automobiles. While it is used with the barrier on the road, there is a strong desire to reduce noise more. Yet the only remedy is to make the barrier higher with cost increase. Therefore, the optimal design is necessary to reduce noise while maintaining the barrier height. More efficient Genetic Algorithm is used to find the optimal shape of NRIM with the reduction of noise lever up to 15 dB. also BEM is used to verify the optimal design results.

Deep sea water has cold temperature, abundant nutrients and minerals, and good water quality that is pathogen-free and stable. Compared with surface water, deep sea water contains more nutrition salt, such as nitrogen and phosphor. Moreover, if has the good balance of minerals. Because of the ability of the spray drying process to produce a free-flowing power considering of spherical particles with a well-defined size distribution and the rapid drying times for heat-sensitive material, spray drying is attractive for a wide range of applications spray drying is a unique unit operation in which powders are produced from a liquid feed in a single processing step. Key component of the process are atomizer, spray chamber. Design of spray chamber should be based on the atomizer type, the production rate, and the particle size required. Because of the complex processes taking place during spray drying, traditional design method are based on pilot-plant tests and empirical scale-up rules. Modern technique such as CFD have a role to play in design and troubleshooting.

The coast area of our country has various tourist attraction factors of its own such as plenty of islands, uncontaminated waters and so on. Nevertheless, sea tourism and leisure facilities have not been developed enough since the national tourist/leisure policies have mainly been focused on the land tourism so far. Recently, the lake and sea areas are becoming more an more popular to people for spending their leisure times, and they, especially the young generations, are eagerly searching for some good ocean spots to enjoy the dynamics maritime sports. In this paper, we worked on the first design phase of environmentally and visually adaptive yacht, taking the cost effectiveness and the safety factors into account as well.

본 연구에서는 취성재료이면서, 세라믹과 유사한 성질을 가지며 내부균열관찰이 용이한 상업용 유리의 표면에 세라믹 플라즈마 용사 코팅한 후 입자 충격시험을 실시하였다. 코팅분말로는 매마모성 및 내충격성이 우수하여 산업계에서 널리 사용되고 있는 $Al_{2}O_{3}$ 분말을 사용하였으며, 충격입자로는 고경도의 STB2 볼베어링강을 사용하였다. 공기압축기를 장착한 입자 충격시험기를 이용하여 강구입자 충격시험을 실시한후, 실체현미경을 이용하여 손상정도를 분석하였다. 그리고 코팅입자의 크기 및 기공율에 따른 손상 정도를 분석 방법에 따라 손상정도를 비교${\cdot}$검토하였다.

In this paper, two different methods are developed to be used for the design of noncontact dry gas seal which is used to prevent gas leakage of high speed rotating shaft-housing machineries. First method is using FEA to compute the deformation of seal face and the other is using Influence Coefficient Method in order to save computation of FEA. In both cases, heat load and mechanical loads are applied such as heat generation, bulk temperature and nodal force, bulk pressure, centrifugal force, respectively. ICM method is verified correct and effective and both methods give reliable and useful deformation results for the design of mechanical seals.

지금까지의 선형 최적화에 대한 연구는 고전적인 최적화 기법인 비선형계획법과 유동해석법을 중심으로 생물의 진화 알고리즘을 바탕으로 한 유전자 알고리즘과 인공지능에 기초를 둔 신경망이론 등이 이용되어 왔다. 또한 최근 컴퓨터의 성능이 급속도로 향상됨에 따라 전산유체역학에 기초한 시뮬레이션 평가기법도 사용되고 있다. 본 논문에서는 유전자 알고리즘을 이용한 선형 최적화 방법을 제시하였다. 그리고 광역 최적해의 효과적인 검색과 빠른 접근을 위한 방법으로 네트워크 시스템을 기반으로 한 병렬분산 유전자 알고리즘 시스템(PDGAS)을 개발하였으며 그 성능을 기존의 진화 알고리즘과 비교${\cdot}$분석함으로써 선형 최적화의 가능성을 확인하였다.

The Study of Hansun(Traditional Fishing Boat of Korea) is based on Fishing Bost Investigation Report which began in 1921. The Report was completed in 1927 with the conclusion of Southern sea Region and Western sea Region studies which included the investigation of the entire region. Based on this report, this paper surveys Hansun's characteristics style of boat and performance. The First couple of chapters are possibility of combining type of Hansun and modern Sailing Boat. As a result we find out that the hull form of Hansun is very similar with that of modern sailing boats and is a good candidate for the mother ship to develop the modern sailing boats for Korean sea.

Resistance performance of 3 G/T class coastal leisure boat is experimentally investigated at high speed ranges and the effect of a fin attached at hull side is studied together. Wave patterns are observed to make clear the relation between the resistance performances and the wave characteristics.

This paper describes a study on the tearing damage of the ship's bottom plating during a grounding. It has been known widely that difference scaling laws are applied for bodies undergoing simultaneously plastic flow and crack propagation in the deformation of the plate tearing. Especially, the basic scaling law is not followed for the fracture. In this study plate cutting experiments for the geometrically similar models have been performed in order to verify the problem. From the experimental results, it has been observed that the cutting forces and energy for the larger models are significantly lower than those of the smaller models the damage become large. A simplified analytical method for the estimation of tearing is proposed based on the experiments and it has been observed that the results of the present formula are correlated very well with the experiments

Model tests using 2.0m model of the series 60 form ($C_{b}$ = 0.6) were carried out in the Circulating Water Channel(CWC) in the Chosun University(CU, Korea) for the purpose of a correlative study with Towing Tank(TT). Resistance, propeller open water, self propulsion, and wake survey tests were carried out and the results were extrapolated to the ship scale. These results were compared with the extrapolated ship values based on the model test of 7.0m model in the TT at the Korea Research Institute of Ships and Ocean Engineering (KRISO, Korea). The CWC test results were correlated with the results of the towing tank tests.

A resource management system of for the paper-bag product company was made. The objective of the system is computering the hand writing management process to improve the performance of working process of the small company. For this, some programming and design strategies were made such as the simplification, ease to use, similarity with old system and object oriented concept. It is expected to reduce burdens and errors of hand writing and improve the efficiencies of small company.

This paper deals with the performance analysis and design of impulse turbine for OWC type wave energy plant. Numerical analysis was performed using a commercially-available software FLUENT. This parametric study includes the variation of several important parameters such as the number and shape of blades, hub ratio and tip clearance. Since parametric study at various flow coefficients requires considerable amount of computing tim, two-dimensional analysis was employed to find out optimum principal particulars in rather simple manner. Full three-dimensional calculation was also performed for several test cases to confirm the validity of two-dimensional approach. Up to the present stage, tentative result is well demonstrating the usefulness of 2-D analysis.

Generally, in jack up rig design for harsh environment, its leg height is a major factor for achieving a sufficient serviceability & operability in terms of the worst environment and the workable depth. Due to difficulties in constructing such a high-slender leg, inaccessibility of yard fabrication equipment, etc. the construction of Jack up rig fur harsh deep sea has not been common. Method using heavy crawler crane, fabrication tower or extension by the floating crane vessel is still conventional construction but, considering high cost fur mobilizing heavy lift vessel (HLV) or additional marine work for implementing preload / full height test at sea, the ground-base construction is much advantageous. Air skidding method (ASM hereafter) is ground-based construction methodology, newly developed due to such requests. ASM could also be extended to similar engineering fields. This paper presents the operating sequence, design parameters and procedure which were verified through successful operation at the end of May 2002.

Laser beam welding process is a relatively new process in comparison with arc welding process, but it is expected to apply widely because of the many advantages, and research and development of that process is being progressed actively for the practical use. the application of this welding process has been restricted due to the high initial investment and the need of precise processing against the material, but cost reduction and thick plate welding in high speed have become practial by recent technological development, and this welding process to not only small parts in automobile, machinery and physicochemical field, but also a large structure and pipe line are being applied. In order to utilize this welding process appropriately to a steel structure, the properties of welding residual stresses and fracture toughness in welded joints are to be investigated for relibilty. On this study, after performing the finite element analysis, thermal and residual stress properties have been examined to the general structural steel (HT50) by laser beam welding. Besides, the property of fracture toughness has been investigated by the Charpy impact test and 3-points bending CTOD test carried out in the range of temperature between $-60^{\circ}C$ and $20^{\circ}C$. From the research results it is revealed that the maximum residual stress appears in the center of plate thickness and the fracture toughness is influenced by strength mis-match.

In order to confirm the possibility of application of laser welding process to 2.25Cr-1Mo steel, the characteristic of residual stress distribution in welds by SMAW and $CO_{2}$ Laser welding process have been investigated and compared using the numerical analysis. As the Result of the numerical analysis, the possibility of application of laser welding process has been found out in respect to the welding residual stress distribution and mechanical properties in welds.

25Cr-20Ni series strainless steel have an excellent high temperature strength, high oxidation and high corrosion resistance. However, further improvement can be creep strength by work hardening prior creep. In the present study, the effect of prestraining at room temperature on the creep behavior of a Class M(STS310S) and a Class A(STS310J1TB) alloy containing precipitates have been examined. Prestraining was carried out at room temperature and range of prestrain was $0.5{\sim}2.5$ % at STS310J1TB and $2.0{\sim}7.0$ % at STS310S. Creep behavior and creep rate of pre-strained specimens were compared with that of virgin specimens. Room temperature prestraining produced the creep life that is longer than that of a virgin specimen both for STS310J1TB and STS310S when creep test carried out at the temperature lower than recrystallization temperature. The reason for this improvement of creep life was ascribable to the interaction between dislocations and precipitates in addition to the dislocation-dislocation interaction in STS310J1TB and the dislocation-dislocation interaction in STS310S. The beneficial effect of prestraining in STS310J1TB was larger than that of STS310S.

This study made an experiment On fatigue crack propagation da/dn, stress intensity factor range ${\Delta}K$ respectively in room temperature and in low temperature. And we got the following characteristics from fatigue crack growth test carried Out in the environment of room temperature and law temperature at $25^{\circ}C$, $-60^{\circ}C$, $-80^{\circ}C$, and $-100^{\circ}C$ in the range of stress ratio of 0.3 by means of opening made displacement. The threshold stress intensity factor range ${\Delta}Kth$ in the early stage of fatigue crack growth (Mode I) and stress intensity factor range ${\Delta}K$ in the stable of fatigue crack growth (Made II) was decreased in proportion to descend temperature. It assumed that the fatigue resistance characteristics and fracture strength at law temperature and high temperature is considerable higher than that of room temperature in the early stage and stable of fatigue crack growth region.

This paper describes the need for a ductile of Fiber Reinforced Plastic(FRP) reinforcement for concrete structures. The criteria to be met by the FRP, which are based on the properties of the steel rebar it is to replace, are threefold: high initial modulus, a definite yield point and a high level of ultimate strain. It is shown that the use of a fiber architecture based design methodology facilitates the optimization of the performance of FRP through material and geometric hybrid. Ductile hybrid FRP bars were successfully fabricated at 3mm and 5mm nominal diameters using an in-line braiding and pultrusion process.

Joining or welding of dissimilar metallic materials is very difficult problem because material properties like heat conductivity, melting points, coefficient of thermal expansion, etc. are different each other and cracks are occurred easily due to formation of intermetallic compounds. Nevertheless, deep attention from great industrial demands and trials to joining dissimilar materials has been increased steadily. In this study, TIG welding of Cu to Al is tried and tensile test, SEM and EDX analysis are carried out.

This paper is concerns with the development of the formulae to predict deformation of curved plate due to line heating. For this purpose thermal elasto-plastic analysis has been carried out for both flat and curved plate models with varying parameters which affect the result of line heating. based on the results of numerical analysis, the formulae for predicting angular deformation has been derived through the regression analysis, which. It has been seen that the present model well agrees with the numerical analysis results and can reflect the curvature effect of plate to be heated. This paper ends with some comments on this formulae.

In a today industry, the welding is doing a many portion in structure manufacture. This study is simulated heat of heat-effected zone and researched a mechanical properties and ultrasonic characteristic in used the SS400 and the STS304. As the result mechanical properties of steel that become drawing decreased because of remaining stress by strain gardening according as simulated heat temperature rises, but according as temperature rises in material that do simulated heat after have done annealing, mechanical propensity was improved. The velocity and attenuation become different by effect of remaining stress than effect of material internal microstructure in ultrasonic wave test. In the case of STS304, there was change in mechanical properties by effect that is by strain hardening, but there was no change in material that simulated heat after annealing. When become drawing in ultrasonic waves test, according as simulated heat temperatures rise, change of attenuation coefficient is looked, but material that simulated heat after annealing was no change almost both the volocity and attenuation.

The shock absorber for vehicles is the important component to absorb the shock in driving. These essential components, piton and piston rod, must be made of S25C, S45C and SCM440 generally depending on kind of vehicles, precisely machined and assembled by the bolt. 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. These factors above necessitate nowadays the domestic development of the shock absorber by friction welding and a new approach of study on real-time quality evaluation by AE techniques.

Rencentely, the request for the light weight is more incresed in the area of industrial environment and machinery and consistent effort is needed to accomplish high strength of material for the direction of light weight. we got the following characteristic from crack growth test carried out in the range of stress ration of 0.1, 0.3 and 0.6 by means of opening mode displacement. At the content stress ratio, the threshold stress intensity factor crack range ${\Delta}K_{th}$in the early stage of fatigue crack growth (Region I) and dtress intensity factor range ${\Delta}K$ in the stable of fatigue crack growth (Region II) with an increase in ${\Delta}K$. Fatigue life shows more improvement in the Shot-peened material than in the Un-peening material. And compressive residual stress of surface on the Shot peening processed operate resistance force of fatigue. So we can obtain fallowings. (1) The fatigue crack growth rate on stage II is conspicuous with the size of compressive residual stress and is depend on Paris equation. (2) Although the maxium compressive residual stress is deeply and widely formed from surface, fatigue life does not improve than when maxium compressive residual stress is formed in surface. (3) The threshold stress intensity factor range is increased with increasing compressive residual stress.

Reduced Activation Ferritic/Martenstic (RAFs) are leading candidates for structural materials of D-T fusion reactor. One of The RAFs, JLF-1 (9Cr-2W-V, Ta) has been developed and proved to have good resistance against high-fluency neutrino irradiation and good phase stability. Recently, in order to clarify the strengthening mechanical at high temperature, a new scheme to improve high temperature mechanical properties is desired. Therefore, the creep properties and creep life prediction by Larson-Miller Parameter method for JLF-1 to be used for fusion reactor materials or other high temperature components were presented at the elevated temperatures of $500^{\circ}C$, $550^{\circ}C$, $600^{\circ}C$, $650^{\circ}C$ and $704^{\circ}C$. It was confirmed experimentally and quantitatively that a creep life predictive e벼ation at such various high temperatures was well derived by LMP.

Natural frequencies of the transνerse vibration of beams with step change in cross-section are obtained by using the asymptotic closed form solution. This closed form solution is found by using WKB method under the assumption of slowly varying properties, such as mass, cross-section, tension etc., along the beam length. However, this solution is found to be still very accurate even in the case of large variation in cross-section and tension. Therefore, this result can be easily applied to many engineering problems.

A study on friction welding of chrome molybedenum steel(SCM440) to carbon steel(S45C) is examined experimentally through tensile test, hardness test. So, this paper deals with optimizing the welding conditions and analyzing various mechanical properties about friction welds of SCM440 to S45C steel. The tensile strength of the friction welded joint was increased up to 100% of the S45C base matal under the condition of all heating time. Optimal welding conditions were n=2,000(rpm), $P_{1}=60(MPa)$, $P_{2}=100(MPa)$, $t_{1}=4(s)$, $t_{2}=5(s)$ when the total upset length is 5.7(mm).

Hull form designers have to design a ship with satisfying an economical, technical and environmental demand. When it is concerned by a technical and environmental demand, there will be a economical demand left to criticize optimization. In this case, there were used to be requirements which needs to meet only a best performance not concerning about input of Human resource. Life cycle's cost contains building cost and operation cost so that now we need to check Man Hour cost in building a ship. This research shows a correlation between hull form information, i.e. curvature, length, breadth and thickness of surface and Man Hour of the Shell plating manufacture with using Artificial Neural Network and Gentic Programming. This study will support to classify initial work, to have a high assumption possible through predicting a Man Hour and to provide a guide book to infer a building cost and a economical optimization hull form.

Thermal elastic-plastic analysis was performed to assess the initial residual stress distribution of welded joints considering temperature dependent material properties. The test model was the idealized boxing fillet specimen, frequently appeared in the joints of longitudinal and transverse members of ship structure. Residual stress relaxations due to external loads were analyzed by subsequent elastic-plastic analysis considering loading and unloading steps, and the characteristics of residual stress relaxations were discussed with the levels of external loads. Additionally, to define the fatigue life of crack initiation and propagation, the S-N data for each crack length were appraised.

Peristaltic mass transfer of fluid in a channel with standing wall oscillations is analyzed. Averaged nonlinear Navier-Stokes equations of motion are examined for a wide range of Reynolds numbers and external pressure drops. Nonpropogating wall oscillations with relatively big amplitudes essentially increase the liquid flow. Most effective intensifying of mass transfer occurred for low Reynolds numbers.

Despite various forms have been developed and applied to ship hull forms, the superiority of hard chine type over other forms of fishing boat has been recognized so far. As one of the ways of forms for new concept fishing boat, this paper presents the result of a performance evaluation for newly developed forms of hull, appendage and deck house, which features that have esthetic forms.

This paper presents the results of slamming experiment using air pressure cylinder to increase the repeatability of the experiment. When it comes to the slamming experiment, the traditional way of doing it has been the free fall experiment. By adopting air pressure cylinder almost equal peak pressures were obtained with that of free fall experiment. Jet takes place when the wedge enters water. Slamming doesn't take place when Dead rise angle is more then 20 degrees.

The motion and time-mean drift force of a 2-D floating BBDB in waves are studied with and without taking account of fluctuating air pressure in the air chamber. It has been found numerically that the drift for a of the BBDB is in the reverse direction of propagation of the incident waves over specific frequency ranges as found by McCormick through his experiment work. The drift force is calculated by Pinkster's near-field method. Since Maruo's formula method for the drift force is always positive, Maruo's formula is only approximate and should be replaced by the correct near-field method.

Three-dimensional cavity flow is analyzed with the code by using unstructured grid. Incompressible Navier-Stokes equations are used as governing equations, and governing equations are discretized by Finite Volume Method. Artificial compressibility method, proposed by Chorin, and developed by Soh, is used for coupling a pressure and a velocity. Cell-centered scheme is adopted in the code, this has the effect of having denser grid than nodal scheme when the same grid is used. Weighted Averaging scheme is used for the value at a nodal point. Cavity flow is analyzed, and this computed results are compared with the results in the research report

Unsteady two-dimensional nonlinear waves which are generated by the numerical wavemaker of plunging type are numerically simulated using a finite difference method in rectangular grid system. Two-dimensional Navier-Stokes equations and the continuity equation are used for the computations. Irregular leg lengths and stars are employed near the boundaries of body and free surface to satisfy the boundary conditions. Marker-density function method is adopted for the simulation of wave breaking phenomena, and the computations are carried out with various wave amplitudes and two section shapes of wavemaker. The computation results are compared with other existing computational and experimental results, and the agreement between the experimental data and the computation results is good.

As the first step to investigate the nonlinear interactions between turbulence and marine structures inside a viscous NWT, a LES technique was applied to the turbulent channel flow for $Re_{T}=150$, in this paper. The employed models were 4 types, such as the Smagorinsky model, the Dynamic SGS model, the Structure Function model and the Generalized Normal Stress model. The simulated data in time-series for the LESs were averaged in both time and space and performed statistical analysis. And results of the LESs were compared with those of a DNS developed in the present study and two spectral methods by Yoon et al.(2003) & Kim et al.(1987). It seems to be quite difficult to evaluate their performances to the present problem, but is seen that the accuracy of LESs are still related to the number of grids(or fine grid size).

As the 2-D hydraulic experimental results for the submerged rubble-mound structure, we have concerned with their stability/function characteristics of structures by the effects of wave force, scour/deposition at the toe and wave transmission ratio at the lee-side sea. And as to investigate the variation characteristics of wave transmission ratio which depended to a geometrical structure of the submerged breakwater profiles, the critical conditions for the depth of submergence and crest width obviously presented. In summary, there results lead us to the conclusions that the wave control capabilities of submerged breakwaters by the variation of the submergence depth is high about 4 time degrees at the efficiency than the that of crest width. The destruction of covering block at the crest generated at the region which located between maximum damage curve, it maximum damage/failure station from the toe of the structure were 0.2L. As the wave transmission coefficient and the slope of the structure increase, the damage/failure ratio and the maximum scour depth at the toe was extended, respectively. When maximum scour depth happened. The destruction of covering block which located at the toe generated at the front slope destruction. Finally, it was found from the results that the optimization of structure may be obtained by the efficiently decision of the submergence depth and crest width in the permissible range of wave transmission ratio.

The viscous interaction of stern wave is studied by simulating the free-surface flows, including sub-breaking phenomena around a high speed catamaran hull advancing on calm water. The Navier-Stokes equation is solved by a finite difference method where the body-fitted coordinate system, the wall function and the triple-grid system are invoked. The numerical appearance of the sub-breaking waves is qualitatively supported by the experimental observation They are also applied to study precisely on the stern flow of S-103 as to which extensive experimental data are available. For the catamaran, computations are carried out for the mono ana twin hulls.

The anchor is laid on seabed and the main engine is worked to against incident environmental loads in typoon. As the main engine is broken down in the storm, the anchor chain is cutted and the vessel is drifted. Although a ship is moored by two point mooring lines to keep the her position, a ship is crashed into a rock because of typoon and the accident of oil spilling may be occured. In this paper, we studied the position-keeping of a ship which is analyized based on the slow motion maneuvering equations considering wave, current and wind. The direct integration method is employed to estimate wave loads. The current forces are calculated by using mathematical of MMG. The two point mooring forces are quasisatatically evaluated by using the catenary equation. The coefficeints of wind forces are modeled from Isherwood’s emperical data and the variation of wind speed is estimated by wind spectrum. The nonlinear motions of a two point moored ship are simulated considering wave, current, wind load in time domain.

The influence of wave forces on the moored ship beside quay was investigated based on in-house ship mooring analysis and ship motion program in this paper. The wind and current are the general environmental factors for the mooring analysis beside quay in the mild weather. However, the weather is becoming rough, the wave phenomenon should be included in the mooring analysis. In this paper, as preliminary stages, each moored rope tension was evaluated based on wind and current environmental condition. The results were compared with those from MOSES, commercial program. In addition to this, wave forces of the ship were calculated in order to solve moored ship motion of equation. We will leave to solve this motion equation as future work.

The head-on collision of two solitary waves are examined using a boundary element method. Attachment, detachment times and alplitudes and maximum run-up times and amplitudes are computed. Consolidation times show local minimum value if two waves are of equal amplitudes are colliding. Attachment times show local maximum value if the amplitudes of two waves are the same. The detachment time show local maximum if two wves are the same. The detachment amplitude show local minimum values if the amplitude e(=a/h) is greater than 0.3.

This paper concerns about an experimental investigation about steering performance of tracked vehicle on extremely soft soil based on DOE(Design Of Experiment) using L8 orthogonal Array. A tracked vehicle model with principal dimensions of $0.9m{\times}0.8m{\times}0.4m$ and weight 167kg was constructed with a pair of driving chain links driven by two AC-servo motors. The tracks are configured with detachable grousers, the span of which can be varied. Deep seabed was simulated by means of bentonite-water mixture in a soil bin of $6.0m{\times}3.7m{\times}0.7m$. Turning radii of vehicle and torques of motors were measured with respect to experimental variables; steering ratio, driving speed, grouser chevron angle, grouser span, grouser height. The effects of experiment variables on steering performance are evaluated.

The Ejector is used to get low pressure, and it has been applied to a lot of industry field like the heat engine, the fluid instrument power plant, the food industry, environment industry etc... because there are not any problem even it is mixed with a any kind of liquid, gas, and solid. The flow characteristics in ejector are investigated by PIV and CFD. The experiment using PIV measurement for mixing pipe’s flow characteristics acquired velocity distribution, .Condition : when mixing pipe’s diameter ratio is 1:1.9, and the flux is $Q_{1}=1.136\;l/s$, $Q_{2}=1.706\;l/s$, $Q_{3}=2.276\;l/s$. Based on the PIV and the CFD results, the flow characteristics in ejector are discussed, and it shows the validity of this study.

Recently there are operating the Floating Vessel with the positioning control unit in ocean. This technology is not open to industrial society as exclusive one. In order to improve technical competition for its domestic product. It is required to develope the relevant product like above subject. This system consist of DGPS System, Unique Analysis, System Network, and Mooring System and so on. Accordingly Model/Field test were carried out to verify its Function / Performance for application of practical product. In this development, we have prepared the successful result to operate the speedy / accurate / stable unit as shown on this subject 'Development of Positioning Control System for Ship and Offshore using the DGPS'. And also it is expected to install this product for ship and offshore unit.

Many port states such as New Zealand. the USA. Australia and Canada have strict regulations to prevent ships which arrive in their port from discharging polluted ballast water which contain harmful aquatic organism and pathogens. They are notified that transfer of polluted ballast water can cause serious injury to public health and damage to property and environment. For this reason. they perceived that the ballast exchange in deep sea is the most effective method. together with submitting the ballast management plan which contains the effective exchange method. ballast system and safety consideration. In this study, we make an effort to develop optimum ballast water exchange management and in result of that. it provide more convenient and stable process to prepare ballast water management plan for Bulk Carrier.

In this paper, current application of VR in naval architecture and ocean eng. Design is surveyed and VR process is implemented in ship navigation system. So far, very sophisticated VR applications have announced but not published yet. The reason not published may be that the application is for the navy ship of which the information could not be opened to the public. Also there is another area implementing Simulation Based Design, i..e., visualization of the integration process from initial design to the manufacturing. Herein, the tendency of VR in this area is surveyed, so the international application of VR is introduced. Trough the analysis the most appropriate applicability of VR in this area can be distinguished. And to show the application, ship navigation VR is programmed using OpenGL graphics software.

This paper constructed the 3D real-time numerical model for which predicts the water quality and movement characteristics of the inner bay, which consider the characteristics of the wind-driven current and density current in estuaries which generated by the river discharge from the Hyeong-san river and oceanic water of the Eastern sea. The constructed numerical model reappeared successfully the seawater circulation current of Yeong-il Bay, which used the input conditions of the real-time tidal current, river discharge and weather conditions at March of 2001 year. Also to observe the wind-driven current and density current in estuaries effected to the seawater circulation pattern of the inner bay, we investigated the analyzation for the each impact factors and the relationship with the water quality of Yeong-il bay

As growing importance and concern of waterfront, we have tried to study its landscape, accessibility, landuse and so on as well as its environmentally sound and sustainable development. In fact we had been under the false thought that it always what we wanted, and it was neglected in its economic value. This paper/ looks at on alternative, the non-market value generated by management of waterfront as public resource. We consider the question : how much are people willing to pay to improve, how much are people want to improve? The contigent valuation method was implemented during Sep. 9 to 14 in 3 beaches ; haeundae, Gwanganri, Songjeong. They are representative waterfronts which have been widely known and visited. We find out that households are willing to pay about $12,000{\sim}16,000$ won per year for improving nature elements and inviting more valuable functions about 3 beaches. Especially we pay attention to defference between cognitive and comprehensive satisfaction 3 beaches and their substructural factors satisfaction such as natural environment, public facilities, recreational facilities and etc.

The waterfront the house it falls to empty, it sprouts and un-waterfront to beggarly more view, showing a high satisfactory degree from elements which of the house environment back is diversified, there is to immigration plan of future and the waterfront the area is high and it was visible the degree which is probably. Also the waterfront against to the development of the area the rate where the development recognizes a necessity will be high, it will be high, it will be pay scheduled one expense from even and the river or the coast the line will choose to the view is visible the answer back own house was many. Here upon the waterfront to development of the which indispensability or development hour (1)sublation of the development which is insensitive, (2)the fixed quantity development which hits to demand and supply, (3)after developing the continuous civil official, (4)the environment friendship development back is indicated with consideration fact.

This study was carried out to check the contingency planning methods under the analysis of oil spill potential and make a guide line to apply the results to the port of Busan. The expected spilled oil drift patterns are considered with the most probable scenarios under the base of the oil spill potential. The results obtained from this study are as follows: (1) Analysis method of oil spill potent was proposed and the applicability was proved by the application example to the port of Busan to make the contingency plan. (2) Responsible oil spill contingency planning methods / flow are suggested considered environmental factors and the oil spill potential. (3) The coastal waters of Busan was consist of rocky flat, man-made solid shore and beach shore. Marine traffic have high density of oil tanker and cargo ship. Also, oil tanker ship are examined in the small ships to be less than 3000t to supply oil to the ship moored / anchored as well as the large amount of oil tank / basin are located along the coast of Busan port. These systems are introduced to make in put data to the analysis of oil spill potential. (4) According to the analysis of historical records of oil spill accident in Busan, the frequency of accidents by cargo ship rank highest and 45% of accidents is caused by carelessness. about 65% of total accidents shows a small spill accident of less than $10k{\ell}$.

In this paper, wave numerical modeling was experimented for the analysis of impact factors for the wave transmission as the incident wave and topographic conditions in the narrow channel sea. Recently, Although the results of many researcher for the wave modelling, numerical equations have limited to simulation of wave transformation effects. Despite of thispresent problems, the models was used to design the coastal structures in barrow channel sites. Finally, this paper estimated the wave model(mild slope eq. model) as the analysis of the wave energy transmission according to changing of impact factors(width of channel, bottom slope in channel, incident wave angle, wave period). As the results of numerical experiment, the major impact factors which influence to wave energy transmission were the width of channel and incident wave direction. But in the case that the width of channel is larger than 3L(L=Length of wave), the reduction of wave energy was small.

In this paper, The statistical properties of ocean waves in the sea area of Hong-do, Korea are examined based on 1998-2002's wave data from a directional wave buoy. Wave data aquisition rate, mean wave heights, frequency of wave direction are summarized. Wave height and period scatter diagrams and n-years return period wave heights are estimated. Wave periods of maximum wave heights are also estimated. Large amplitude wave characteristics during the typhoon Prapiroon in 2000, Rusa in 2002 are also examined.

The Sectional and Spatial failure modes are discussed using the experimental data with long crest wave and multi-directional waves considering the failure modes occurring around the rubble-mound breakwater. The spatial & sectional stability and failure mode around the rubble-mound structures with construction progress can be summarized as follows: 1) The rubble mound structures at basic construction step was occurred serious failures when ${\xi}$ was about 6.5. 2) It was clarified that the failure modes at the round head of detached breakwater are classified as failure by plunging breaking on the slope, failure by direct incident wave force and failure by scouring at the toe of the detached break water. 3) The failure mode was found in the lower wave height than the design wave by the breaker depth effect. 4) The failure on the slope were also developed at the lee side of the round head because diffracted wave propagated into the behind area by grouping effect of multi-directional irregular wave.

A basic design on a flexible riser in a floating type development system for upwelling deep ocean water is presented. In the numerical study, an implicit finite difference algorithm is employed for three-dimensional riser equations. Fluid and geometric non-linearity and bending stiffness are considered and solved by Newton-Raphson iteration. To keep the depth of end point of a flexible and light riser is very important for upwelling deep ocean water in a floating type development system. Weight attached at the end point of the riser in order to keep its intake depth is designed under the strong surface current and the configuration of the riser is predicted. The results of this study can be contributed to the design of the development system in floating type for upwelling deep ocean water.

Aquaculture have been important role to supply food resources for mankind. However, competitive power of domestic mariculture industry was declined due to increase of labor and feed expenditures, and quantity import of low-priced livefishes from the developing underdeveloped nations in North and South East Asia. Mass production and quality enhancement can be pointed out to overcome such an industrial environment in this decade. To meet these requirement, movable mariculture base remodeling feasible vessel of chemical tanker or crude oil carrier has been proposed for more advanced mariculture management system by using deep seawater from about 200m which is sustainablely clean, nutrient-rich and cold seawater. Deep seawater can be applied for control of seawater temperature for mariculture base and cultivation phytoplankton and seaweed as feed. Besides mariculture, strategic marketing can be implemented by raw water and ice of deep seawater. Feasibility of applying deep seawater was considered after evaluating general movable mariculture base and management system.

Deep Ocean Water is formed within restricted area including polar sea (high latitude) by cooling of surface seawater and globally circulated in the state of insolation with surface seawater. Although not as obvious as estuaries mixing, Brine groundwater is mixture of recirculated seawater and groundwater. Seawater having high osmotic pressure infiltrate into unconfined aquifer where is connected to the sea. The ions dissolved in seawater are present in constant proportions to each other and to the total salt content of seawater. However deviation in ion proportions have been observed in some brine groundwater. Some causes of these exception to the Rule of constant proportions are due to many chemical reactions between periphery soil and groundwater. While Deep Ocean Water (DOW) have a large quantity of functional trace metals and biological affinity relative to brine groundwater, DOW have relatively small amount of harmful bacteria and artificial pollutants.

A digital data logging system has been developed for the purpose of a compact offline Ocean Bottom Seismometer(OBS). The Digital Data Logger(DDL) consists of A/D system, Micom with storage memory and firmware managing data files. The A/D system acquires data of 16bit/4ch with sampling rate of 250Hz per channel. The Micom, a micro controller board with T33521 processor of 8051 class, was equipped with 8 flash memories of 128MB for data storage capacity of 1GB. The firmware stores the acquiring data in form of binary files. The DDL was designated to be compact and light and to consume low energy as possible. The DDL is to interface with PC through USB(Universal Serial Bus). The performance of the DDL has been validated through tests with respect to a 3-axis seismometer.

This study, as a basic study for establishing a influence forecasting/estimating model when drain the deep sea water to the ocean after using it, carried out studies as follows; 1) estimating the amount of river discharge and pollutant loads inflowing into the developing region of deep sea water in East Sea, Korea 2) a field observation of tidal current, vertical distribution of water temperature and salinity, and 3-D numerical experiment of tidal current to analysis physical oceanographic status. The amount of river discharge flowing into the study area was estimated about $462.6{times}10^{3}m^{3}/day$ of daily mean in 2002 year. annual mean pollutant load of COD, TN and TP were estimated 7.02 ton-COD/day, 4.06 ton-TN/day and 0.39 ton/day, respectively. Field observation of tidal current results usually show about $20{\sim}40cm/sec$ of current velocity at the surface layer, it indicated a tendency that the current velocity decreases under 20cm/sec as the water depth increases. We could find a stratification within approximately the depth of 30m in field observation area, and the depth increases. We could find a stratification within approximately the depth of 30m in field observation area, and the differences of water temperature and salinity between the surface layer and bottom layer were about $18^{\circ}C$ and 0.8 psu, respectively. On the other hand, we found that there was a definite as the water mass of deep sea water about 34 psu of salinity.