• The Journal of Korean Academy of Prosthodontics
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• v.54 no.1
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• pp.35-40
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• 2016

The maxillary defects lead to anatomical and functional deformity of the maxillofacial region. As far as functions are concerned, such defects can produce difficulty in speech, mastication, and deglutition. Obturator prostheses play a very important role in functional recovery for post-maxillectomy patients. To achieve rigidity of the obturator, appropriate retention should be given, and the weight of the prosthesis be reduced. There are two types of hollow bulb obturator: open and closed. A closed type has many advantages. Nevertheless, some problems, including complexity of fabrication and water leakage into the bulb, have the closed hollow obturator not be widely used. The one-step polymerization technique described in this case overcomes the shortcomings by easily constructing a small hollow bulb with two thermoplastic resin sheets.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2009.11a
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• pp.345-345
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• 2009

전기화학적 환원 기술을 이용한 고온 용융염 전해환원의 결과 생산되는 금속전환체는 다공성 특성에 의해 전해환원의 매질인 용융염을 함유하게 된다. 전해환원과 후속 전기화학 공정인 전해정련의 전해질은 각각 LiCl과 LiCl-KCl 공융염으로 상이하기 때문에 이렇게 금속전환체에 포함된 LiCl 염이 동반되어 전해정련 공정에 도입될 경우 전해정련 공정의 공융염 조성을 어긋나게 한다. 이에 따라 금속전환체의 잔류염은 효과적으로 제거되어야 하며 공정으로 감압 증류에 의한 잔류염 제거 공정이 고려되고 있다. LiCl은 증기압이 비교적 낮기 때문에 감압의 고온 조건이 공정에 필요하다. 그러나 상평형도 분석 결과 전해환원 공정에서 산화물을 담아 음극으로 사용되어 환원된 금속전환체와 함께 도입되는 SUS 재질의 바스켓과 사용후핵연료 금속전환체의 주된 원소인 우라늄과는 공융할 수 있기 때문에 LiCl 증발 온도는 $720^{\circ}C$ 이하로 유지되어야 한다. 이와 같은 조건에서 LiCl 증발 속도를 높이기 위해서는 감압 조건이 필수적이다. 본 연구에서는 감압조건에서 LiCl 휘발 실험을 위해 폐쇄형 및 개방형 반응기를 제작하여 압력 조건 및 Ar 유량 등에 따른 LiCl 휘발율을 측정하였다. 증발된 LiCl은 일정 감압 조건에서 분말형으로 냉각부위에 회수 될 수 있었으나 완전 진공 조건에서는 결정형으로 냉각 부위에 응축되는 것으로 확인 되었으며 일정 진공 조건에서는 Ar 유량에 따라 증발량이 의존하지 않는 것으로 나타났다. 연구 결과 증발염의 취급 빛 이송을 위해 분말형 회수를 목표로 설정할 수 있었으며 공정조건으로 일정 수준의 감압 조건을 제시하였다. 이 후 후속 연구로 장치의 대형화 및 증발 속도 향상을 위한 추가적인 연구가 계획되어 있으며 연구 결과에 기초하여 공학규모 파이로 공정 시설인 PRIDE에 도입될 장치의 기초 설계 자료를 생산할 예정이다.

• The Journal of Korean Academy of Prosthodontics
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• v.54 no.2
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• pp.167-171
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• 2016

Patients undergone partial maxillectomy experience post-operative masticatory, phonetic, and swallowing difficulties. They also encounter social and psychological challenges due to changes in their facial appearances. Thus, functional and esthetic recovery through maxillofacial prosthesis becomes significant for these patients. The objective of an appropriate obturator is to restore palate and improve phonetic and swallowing ability by separating the oral cavity, nasal cavity, maxillary sinus, and nasopharynx. In this case report, an obturator was fabricated for a patient who had partial resection from the maxillary posterior region to the pharynx due to squamous cell carcinoma. The purpose of this case study is to describe the results because the patient was successfully improved both functionally and esthetically.

• Prospectives of Industrial Chemistry
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• v.22 no.5
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• pp.1-13
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• 2019

국제해사기구(IMO, international maritime organization)는 2015년부터 배출규제해역(ECA, emission control area)을 운항하는 선박은 황 함유량이 0.1%(m/m) 이하로 강화된 기준을 만족하는 연료를 사용해야 하며, 2020년부터는 모든 선박에 대해 황 함유량이 0.5%(m/m) 이하인 연료를 사용하거나 동등 이상의 성능을 갖는 배출가스 후처리 장치의 설치를 의무화하였다. 이에 따라, 선박에서 배출되는 오염물질을 제어할 수 있는 다양한 기술이 개발되고 있으며, 후처리 관점에서 습식 스크러버(wet scrubber)는 선박의 디젤 엔진에서 배출되는 이산화황(sulfur dioxide)을 저감시키기 위한 가장 적합한 해결책으로 알려져 있다. 습식 스크러버는 해수를 사용하는 개방형 스크러버(open loop scrubber)와 화학세정수를 사용하는 폐쇄형 스크러버(closed loop scrubber)로 구분된다. 습식 스크러버는 오염물질의 효율적인 처리가 가능하지만 유지보수비가 비싸고, 폐수 발생으로 인한 2차 오염발생 및 부식에 매우 취약한 단점이 있다. 따라서 최근에는 스크러버 내부의 부식을 방지하기 위한 내부식성 재질에 관한 연구와 흡수제(absorbent)의 고도화 연구가 활발히 진행되고 있다. 또한, 하이브리드형 스크러버(hybrid scrubber)는 개방형과 폐쇄형 스크러버의 장점을 결합한 기술로 황산화물의 배출을 규제하는 배출규제해역에서는 폐쇄형 스크러버를 가동하고, 선박이 공해상으로 진입할 경우 개방형 스크러버로 전환함에 따라 황산화물 배출 및 반응 후 세척수의 폐수배출 기준을 동시에 만족할 수 있다.

• 한국생물공학회:학술대회논문집
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• 2000.11a
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• pp.473-474
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• 2000

Ozone has a potency for disinfection, deodorization, decolorization and decomposition of organic materials by strong oxidation. therefore we used the ozonizer to disinfection and deoderization of a piggery. CFU of the ozonated piggery was lower than the others. And the of ozonizer was redesigned from open-type to close-type to obtain high ozone concentration. We was also investigated the effect of air velocity to ozone concentration.

• Journal of Dental Rehabilitation and Applied Science
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• v.27 no.3
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• pp.337-342
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• 2011

Congenital or traumatic loss on the oral and maxillary area or the loss of jaws due to the surgical excision of a tumor causes functional problems, such as masticatory and swallowing disorders, phonetic problems and psychological disorders in patients. In most cases, a prosthetic restoration is needed to resolve these problems and restore the damaged tissue and function. When loss occurs on the maxilla, foods and liquids leak into the nasal cavity, and a nasal sound can be heard due to air leakage into the removed area. In these cases, the palatal obturator can be used to improve the esthetic and functional aspects because it restores the removed area of the maxilla and closes the opened route between the oral cavity and maxillary sinus or nasal cavity. In this case report, a palatal obturator was applied to patients who had a hemimaxillectomy due to the occurrence of squamous cell carcinoma on the right maxillary area. Therefore, fundamental functions, such as phonetic and swallowing functions were restored, and the esthetic aspects of the facial profile were improved.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.12
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• pp.120-130
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• 2020

This study examined the effects of perceived value (functional value, social value) and stress (complexity, insecurity) on continuous intention in SNS. In particular, this study examined the direct and indirect impacts of SNS type on the intention of continuing to use SNS. The research model was tested for 461 respondents that used SNS. SPSS 21.0 and PLS 2.0 techniques were used to perform reliability, feasibility, path and hierarchical regression analysis. The summary of the research results is as follows. First, the results indicate that functional value and social value have positive effects on satisfaction. Second, the results indicate that complexity had a negative effect on satisfaction. Third, the results indicate that insecurity and satisfaction have positive effects on continuous intention. Fourth, the results indicate that SNS type had a negative effect on continuous intention. Fifth, it was shown that SNS type had a moderating effect in the relationship between insecurity and continuous intention. Specifically, Insecurity had a stronger effect on continuous intention at closed-type SNS than open-type SNS. These findings suggest that closed-type SNS companies will have to address the anxiety of SNS users by providing various items and system devices.

• Journal of Wetlands Research
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• v.15 no.1
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• pp.51-58
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• 2013

In this study, the hydraulic experiments were conducted for the dredging efficiency of the cutter head type, which includes the open type and the close type cutter head. The dredging experimental instrument was installed in the large water tank which has the dimension of $4.9m(L){\times}2.2m(W){\times}1.5m(H)$. The dredging experiments were performed for the various conditions of dredging depth, rotating speed, and suction speed of the cutter head. As the results, the dredging efficiency of the close-type cutter head is much higher than that of the open-type cutter head. The dredging efficiency of the same cutter head type was mainly influenced by the rotating speed of cutter head. Also the adequate suction speed of the cutter head is needed for more effective dredging.

• Journal of Technology Innovation
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• v.24 no.2
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• pp.21-56
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• 2016

Despite many previous studies on catch-up, understanding on the effect of product architecture developed by latecomers on the catch-up performance remains limited. On the other hands, in contrast to the semiconductor, ship building, and automotive industry, even if Korean industry and government have invested the development of numerical controllers for machine tools in the past four decades, the industry and government have failed to achieve catch-up. Therefore, we newly examine the effect of product architecture on the catch-up performance of the Korea by implementing comparative research with periods on the evolution of product architecture of Fanuc's numerical controllers, which have achieved the largest market share in the world. We found that Fanuc developed open modular architecture based numerical controllers and provided product with customization of user requirements as well as cost effectiveness. Consequently, Fanuc has sustained market leader position since the mid-1980s. However, despite all the efforts of the industry and government, we found that the Korea failed to develop open modular architecture based numerical controllers and could not achieve significant catch-up performance. Our findings provide important theoretical backgrounds for examining the catch-up performance as well as investigating the reason why latecomers failed to achieve market catch-up even if they accomplished technological catch-up.

• Journal of Digital Policy
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• v.1 no.2
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• pp.1-8
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• 2022

In case of a dangerous situation, the roof, which serves as an emergency exit, must be open in case of fire according to the Fire Act. However, when the roof door is opened, it has become a place of various incidents and accidents such as illegal entry, crime, and suicide. As a result, it is a reality to close the roof door in terms of facility management to prevent crime, various incidents, and accidents. Accordingly, the government is pushing to legislate regulations on housing construction standards, etc. that mandate the installation of electronic automatic opening and closing devices on rooftop doors. Therefore, in this paper, an intelligent emergency door opening/closing device system is proposed. To this end, an intelligent emergency door opening and closing system was developed by linking wired and wireless access counting and AI image analysis. Finally, it is possible to build a wireless communication-based integrated management platform that provides remote control and history management in a centralized method of device status real-time monitoring and event alarm.