• Journal of Radiation Protection and Research
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• v.34 no.3
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• pp.107-114
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• 2009

A Compton camera, which is based on Compton kinematics, is a very promising gamma-ray imaging device in that it could overcome the limitations of the conventional gamma-ray imaging devices. In the present study, the image quality of a rotating Compton camera was evaluated by using 4-D Monte Carlo simulation technique and the applicability to nuclear industrial applications was examined. It was found that Compton images were significantly improved when the Compton camera rotates around a gamma-ray source. It was also found that the 3-D imaging capability of a Compton camera could enable us to accurately determine the 3-D location of radioactive contamination in a concrete wall for decommissioning purpose of nuclear facilities. The 4-D Monte Carlo simulation technique, which was applied to the Compton camera fields for the first time, could be also used to model the time-dependent geometry for various applications.

• Journal of the Korea institute for structural maintenance and inspection
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• v.16 no.2
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• pp.104-112
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• 2012

The failure of tenon in a traditional wood-framed structure may collapse of the entire structure. This study evaluates the strength and stiffness of tenon joints between the beams and pillars through experimental study and suggests reinforcing method of the tenon joint without dismantling the main structures. The main experimental parameters are the number, distance, shape, and inserting depth of spiral-shaped reinforcing steels. As the thickness of the tenon in beams increases, the strength and the initial shear stiffness of the joint increases and, however, the tenons in pillar becomes weaker, resulting in the safety problem of the structure. It is recommended that three spiral-shaped reinforcing steels be placed in the central parts of the tenon to effectively improve the strength and the shear stiffness of the joint.

• Journal of the Korea Fashion and Costume Design Association
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• v.9 no.3
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• pp.221-230
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• 2007

This research was focused on the changes of layered techniques in Hussein Chalayan's collections. For this purpose, the layered techniques in 134 works from Chalayan's collections, 97S/S to 06S/S, which were obtained from fashion magazines and fashion internet site, were analyzed and classified into 15 groups. Layered techniques in his works apparently expressed his philosophy about deconstruction. Multilayered feeling was given through using various techniques such as one layer clothing which was showed like multi-layered clothing. Others were multi-layer clothing which felt like one layer, breaking the stereotyped line of clothing into atypical construction and using various materials or constructive lines which made the optical feeling like one layer or multi-layer clothing, and so on. These layered techniques in Chalayan's collections were differentiated into several categories, such as techniques which were revealed in every collections, techniques which were differentiated from one another collections, techniques which were continuously showed through three collections for connection with each collection, techniques which were used only for Spring/Summer season, and techniques which were uniquely showed in early collection or recent collections.

• Resources Recycling
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• v.31 no.4
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• pp.3-11
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• 2022

Owing to the increasing demand for electric vehicles (EVs), appropriate management of their waste batteries is required urgently for scrapped vehicles or for addressing battery aging. With respect to technological developments, data-driven diagnosis of waste EV batteries and management technologies have drawn increasing attention. Moreover, robot-based automatic dismantling technologies, which are seemingly interesting, require industrial verifications and linkages with future battery-related database systems. Among these, it is critical to develop and disseminate various advanced battery diagnosis and assessment techniques to improve the efficiency and safety/environment of the recirculation of waste batteries. Incorporation of lithium-related chemical substances in the public pollutant release and transfer register (PRTR) database as well as in-depth risk assessment of gas emissions in waste EV battery combustion and their relevant fire safety are some of the necessary steps. Further research and development thus are needed for optimizing the lifecycle management of waste batteries from various aspects related to data-based diagnosis/classification/disassembly processes as well as reuse/recycling and final disposal. The idea here is that the data should contribute to clean design and manufacturing to reduce the environmental burden and facilitate reuse/recycling in future production of EV batteries. Such optimization should also consider the future technological and market trends.

• Journal of the Korea Institute of Building Construction
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• v.22 no.6
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• pp.681-688
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• 2022

In this study, the process of drone photography, automatic volume calculation, total floor area conversion, and waste calculation was constructed as a QGIS plug-in to predict the demolition waste (DW) generated in an aged area where drawing information or building information is uncertain. Through a case study, the high consistency between the automatically calculated volume using the drone and the BIM volume based on the field measurement was confirmed. Field application was carried out for the planned demolition work site, and the consistency between the drone-based volume and the actual measurement-BIM-based volume was reconfirmed. The waste generation unit was applied and the amount of DW was calculated by setting the floor height and building type, and the entire process was completed within 6 hours. Although the difference between building information and building objects through drones occurred according to the setting of temporary structures, loads, and floor heights, it was found that the actual amount of DW was generated more than the initial estimate. It is expected that measures to improve the accuracy of volume and floor area conversion will be required through case studies in the future.

• Conservation Science in Museum
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• v.29
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• pp.47-64
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• 2023

Daehye Bogakseonsaseo (Letters of Master Bogak) in the possession of the National Museum of Korea is a Goryeo-era book produced in 1387, which was acquired in 2005 in a state of severe general damage. Subsequently, its production techniques and materials were examined using bibliographical characteristics and scientific analysis, based on which an overall conservation treatment was carried out. Janghwang(mounting) in bibliographical characteristics is a five-hole-stitch binding (五針眼線裝本), a single-lined rectangular box (四周單邊), and no column lines. The conservation treatment was examined in two aspects: the basic form and the conservation treatment process. The book is composed of the outer cover, original cover, end paper, and inner paper of 0.04-0.07mm thick, which is significantly thinner than general book paper. The conservation treatment was applied after the entire book was disassembled, based on the assessment that both the cover and the inner sheets of paper were in a dire condition due to deterioration. The conservation treatment comprised of the process of disassembly, cleaning, reinforcement of defective parts, scanning, and binding, with a paulownia box made for its storage. At the time of disassembly, samples were made for the inner sheets and the book string in order to conduct fiber identification. The fibers were identified using Safranin and C-stains. Safranin staining identified a thick fiber wall, in addition to cross-marking, dislocation, and transparent membranes. C-stain staining identified the fiber as mulberry, given the dark red residue. The book strap has a flat, circular cross-section, and was identified as cotton fiber, since a lumen was observed in the center.

• Explosives and Blasting
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• v.13 no.4
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• pp.73-81
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• 1995

Explosives demolition mothod is allowed for more efficient time-saving and safer demolitioni operations as compared to conventional / mechanical demolition methods. CDI has to minimize the effects of noise, dust and various demolition hazards to the public areas, and residences that are located adjacent to the project site. CDI's explosives demolition work on the Nam san Foreigner's Apartment Complex and chosun trading Co's factory are backed by over 45 years of explosives experience in the demolition of over 6,000 structures worldwide, many of these structures are similar to the Nam san Foreigner's Apt. and Chosun trading's factory in construction and proximity to sensitive adjacent exposures. Recoginized worldwide as the founder of the leader in explosives demolitioni technology, CDI always will applied "State-of-the-Art" explosives techniques to safely and successfully achieve the desired demolition results on these project. CDI has never injured, much less caused any fatality, to either a worker on one of our sites or to a third party during the implosion of high-rise structure.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2014.10a
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• pp.69-71
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• 2014

최근 해운고객 업체의 높은 서비스 기대에 따른 다양하고 질 높은 서비스 개발이 필요하다. 해운사업의 4대영역인 운임시장, 신 조선시장, 중고선 매매시장 및 해체시장의 점진적 확대되고 있다. 본 논문에서는 해운선사가 제공하는 서비스와 관련된 문헌연구를 고찰하여 해운선사의 현황을 파악하고, 이들이 제공하는 서비스 질 향상을 위한 전략 수립 시 사용할 수 있는 평가요인을 도출하여 요인 간의 상대적 중요도를 제시하고자 한다.

• KEPCO Journal on Electric Power and Energy
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• v.5 no.4
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• pp.263-273
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• 2019

South Korea's OF cable is reaching its expected design life of 30 years, and as a result, the risk of failure is increasing. Therefore, it is necessary to diagnose the long-term operating OF cables through accurate diagnosis at the right time to prevent the failure. Currently, the KEPCO periodically conducts DGA. However, the gas found in DGA is caused by oil deterioration as well as insulation paper. Therefore, the analysis of the degree of polymerization and furan compounds which is an evaluation of insulation paper considered to be the life of OF cables is required. In addition, the results of the evaluation of deterioration of insulation paper need to be checked for correlation with the results of DGA. In this study, DGA carried out through GC, the degree of polymerization was analyzed using an automatic viscometer, and HPLC was used to detect the furan compounds. In addition, the obtained results were applied to the SVM technique, which was recently introduced to determine abnormalities in OF cable. And the results which were accurate and reliable were obtained.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.7 no.2
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• pp.115-124
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• 2009

Cryogenic cutting technology is one of the most suitable technologies for dismantling nuclear facilities due to the fact that a secondary waste is not generated during the cutting process. In this paper, the feasibility of cryogenic cutting technology was investigated by using a computer simulation. In the computer simulation, a hybrid method combined with the SPH (smoothed particle hydrodynamics) method and the FE (finite element) method was used. And also, a penetration depth equation, for the design of the cryogenic cutting system, was used and the design variables and operation conditions to cut a 10 mm thickness for steel were determined. Finally, the main components of the cryogenic cutting system were manufactures on the basis of the obtained design variables and operation conditions.