• Journal of Radiation Protection and Research
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• 제10권2호
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• pp.113-121
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• 1985

방사성폐기물 처리, 처분의 안정성 평가를 위하여 방사성 고화체에서 용출되는 $^{137}Cs$과 $^{90}Sr$의 방사능 용출율과 누적용출분율을 계측 분석하여 시멘트를 사용한 방사성 고화체에서 $Cs^+$과 $Sr^{++}$의 용출특성을 조사하였다. 모의방사성 폐액의 몰농도, 시멘트의 종류, 첨가물질 및 붕산농도 등을 변화시키면서 sodium silicate 법과 중화법으로 원주형 시멘트 고화체를 제작하였다. 여기에서 가압경수로형 원자력 발전소의 모의 농축폐액의 시멘트 고화체로부터 용출연구는 IAEA의 추천방법에 따라서 수행되었다. 실험결과는 대부분 이미 보고된 연구자료들과 잘 일치하고 있으나 수밀성 시멘트 고화체에서는 상당히 높은 방사능 용출율을 보여주고 있음으로써 방사성 폐기물 고화체에 그 사용이 적합하지 않음을 알게 된다.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2005년도 추계학술대회 논문집
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• pp.75-80
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• 2005

선박 침수 사고의 경우, 선박의 운용 책임자가 취할 수 있는 대응방안이 한정되어 있어 정확한고 신속한 의사결정을 위해서는 기존의 안전관련 시스템을 활용한 효율적인 의사결정 지원 시스템이 필요하다. 수밀 및 준수밀 문, 격벽 밸브, 배수 펌프 둥과 같이 침수 사고 시 작동하는 대부분의 시스템들은 침수가 선박 전체로 전파되는 것을 막도록 충분한 구획분할 정도를 확보하는데 목적이 있다. 침수 시나리오가 파국적이지 않다고 가정하더라도 발라스트 탱크의 사용은 침수 전파 방지와 선박 안정성을 향상하기 위한 매우 효과적인 방안이 될 수 있다. 본 논문에서는 침수 손상 시 최적의 대응방안을 위해 채워져야 하는 발라스트 탱크들을 선정하고, 각 발라스트 탱크의 수위를 결정하는 최적화 알고리즘을 기술한다.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2005년도 추계학술대회 논문집
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• pp.135-140
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• 2005

항만과 해역에 설치되는 수직벽의 일례로 육상 및 유입되는 오염수의 오염 유출 방지를 위한 차수기능을 갖는 차수벽과 교량이나 댐, 갑문 둥의 하천 또는 해양구조물을 축조하는 동안 물이 들어오는 것을 방지하기 위하여 임시로 설치되는 가물막이(cofferdam)벽 등이 있다 이들 차단벽의 구조역학적인 설계 인자 중 유입수 유동 특성과 설치 지역의 지반 특성이 중요한 의미를 가진다고 판단된다. 본 연구에서는 이러한 수직 차단벽 주위의 유체역학적 특성 파악의 일례로 수직벽의 하단에 틈새를 갖는 파공(perforation)이 발생하였을 때 이들 파공의 개도율 변화에 따른 유동특성을 고찰하는 하나의 방안으로 입자영상유속계(Particle Image Velocimetry)를 이용하여 수직벽 후류 특성을 실험적으로 고찰하였다.

• 한국실내디자인학회논문집
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• 제16호
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• pp.59-67
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• 1998

This study classifies distinctive peculiarities of cruise interior design which is different from that of structures on the land through the theoretical study on the cruise equipped with functions of hotel and ship. The distinguishing marks are : The first one of the main peculiarities is associated with the International agreement and the safety of passangers and the ship required by the specific regulation. The cruise interior design should be also selectively chosen. The third in comply with the peculiarity of the space plan the base of planning the cruise spaces are as follows : The course of bow and stern the pillar the center line of ship main vertical bulkhead watertight subdivision bulkhead and the deck. The last by special peculiarity of construction materials, materials and products applied for the cruise should meet the regulation of SOLAS and IMCO.

• 한국군사과학기술학회지
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• 제16권2호
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• pp.111-117
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• 2013

In this paper, we have proposed novel technique to improve maintainability for training vehicle of underwater weapon system. In case of under water weapon, the fire procedure is related with operation of expulsion system in submarines. So the submarine crews should practice the complex fire procedure of weapon system by using training vehicle, which is safer and cheaper than operational weapon. After emitted from submarine, the training vehicle rise to the surface and should be withdrawn from the sea. The recovered training vehicle is transported to maintenance depot and pass through the recycling procedure including disassembling the vehicle, data acquisition & analysis, battery charge, replacing expandable components, testing the captive equipment, and assembling the vehicle. The disassembling & assembling of training vehicle which is composed of watertight section or airframe, is time-consuming work. So in this paper, we have studied the elements of recycling procedure and propose the method to exclude the assembling & disassembling work for maintainability improvement.

• 대한조선학회논문집
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• 제40권4호
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• pp.53-58
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• 2003

Design of the corrugated watertight bulkhead for a bulk carrier is principally determined by the permissible limit of Classification requirements. As the weight of upper and lower stool has considerable portion of the total weight of the transverse bulkhead, optimum design including the stool geometry and size will play an important role on economic shipbuilding. The purpose of this study is focused on the minimization of steel weight using the design variables, which are the shape and the size of the corrugation as well as the upper and lower stools. Discrete variables are used as design variables for the practical design. In this study, the evolution strategies (ES), which can highly improve the possibility of leaching the global minimum point, are selected as an optimization method. Usefulness of this study is verified by comparison with the proven type ship design. As objective function, total weight of the transverse bulkhead including the upper and lower stools is used.

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2001년도 추계학술대회 논문집
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• pp.156-159
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• 2001

Recently, side scan sonar system has been developed and operated to survey cable laying, sunken bodies, geometry of sea bottom and so on. It uses the acoustic signals, which are emitted from two transducer arrays, left and right sides, to get geometric information of the specified area. This system consists of transceiver board, towed body, deck unit and GPS receiver. The transceiver board, nested in a watertight canister, controls the transmitting and receiving of the acoustic pulses from transducer arrays. After receiving the scattered signals, it processes BP(Band Pass) filtering, AGC(Automatic Gain Control), TVG(Time Varying Gain) and Heterodyne. The deck init has the signal processing part, A/D converter, power supplier, and real-time monitoring part. The towed body has been designed to satisfy the optimal hydrodynamic behavior during towing, In this paper, brief introductions on the design theory of transceiving part and some results from the field which have been operated recently will be introduced.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2004년도 춘계 학술발표회 제16권1호
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• pp.152-155
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• 2004

Recently constructions of large scale infrastructures have been tending upwards, due to continuous growth of economy and increase of demands. In addition, hydration heat occurs rapidly in early age just after casting of concrete owing to higher strength and massive structure of concrete. Consequently, cracks and residual stress are developed in accordance to field condition. Moreover, These have harmful influences on safety, durability, watertight, waterproof, and shape of concrete structure. In this study, hydration heat tests were conducted on three of self-compacting concrete and one of high strength concrete. Heat generation and temperature are compared and evaluated based on the test results.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 1993년도 봄 학술회 논문집
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• pp.49-58
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• 1993

Reappraisal of the design and the construction concept of the bottom drainage tunnel has been made through the seepage analysis. An appropriate design approach for this tunnel has also been proposed. It was revealed from this study that water pressures acting on the concrete lining in the bottom dralnage tunnel much depend on the permeability of the surrounding ground, the source of water supply and the discharge capacity of dralnage facilities. The full release of these water pressures by the current drainage system could not be expected if this type of tunnel is constructed in the ground including alluvial deposits having a high permeability. The necessity of a proper reinforcement of the concrete lining or a modification of its shapes corresponding to the water pressure has been suggested.

• 한국항해학회지
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• 제23권3호
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• pp.17-28
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• 1999

Concerns related to the safety of bulk carriers we, most of all, the increasing number of bulk carrier accidents which amount to 425 during last 20 years; half of them are totally lost. A number of bulk tarriers are still missing. Bulk carrier safety has become an international issue since 1995. The International Maritime Organization (IMO) embarked on the legislation as a countermeasure to the increasing number of the bulk carrier accidents. The IMO discussed in the safety of bulk carriers including the strength of transverse watertight bulkheads, especially when the ship carries high density cargoes and the damage stability of bulk carriers in the flooded condition. In this study, statistics and causes of accidents of bulk carriers are analyzed in order to identify special features of bulk carrier accident and causes of the casualty. This study examines certain cases of hull collapses and severence which resulted in sinking to infer possible causes of missing ships.