• Journal of Welding and Joining
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• 제23권3호
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• pp.76-82
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• 2005

Recently the application of laser welding technology has been considered to shipbuilding structure. However, when this technology is applied to primer coated steel, good quality weld beads are not easily obtained. Because the primer-coated layer caused the spatter, humping bead and porosity which are main part of the welding defect attributed to the powerful vaporizing pressure of zinc. So we performed experiment with objectives of understanding spatter and porosity formation mechanism and producing sound weld beads in 6mmt primer coated steels by a $CO_2$ CW laser. The effects of welding parameters; defocused distance, welding speed, coated thickness and coated position; were investigated in the bead shape and penetration depth on bead and lap welding. Alternative idea was suggested to suspend the welding defect by giving a reasonable gap clearance for primer coated thickness. The zinc of primer has a boiling point that is lower than melting point of steel. Zinc vapor builds up at the interface between the two sheets and this tends to deteriorate the quality of the weld by ejecting weld material from lap position or leaving porosity. Significant effects of primer coated position was lap side rather than surface. Therefore introducing a small gap clearance in the lap position, the zinc vapor could escape through it and sound weld beads can be acquired. In conclusion, formation and suspension mechanism of the welding defects was suggested by controling the factors.

• 대한기관식도과학회지
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• 제13권1호
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• pp.33-38
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• 2007

Background and Objectives: A plunging ranula represents a mucus escape reaction occuring because of the disruption of the sublingual salivary gland. It is commonly a condition of young adults, although the reported age range is 6-43 years. There is said to be a slightly female preponderance of about 1.9:1(F:M). Surgical incision has been considered the definite treatment, but sometimes complete excision is very difficult. Non-surgical treatment of these lesions has been attempted, but the results have not been satisfactory. In this study, we present our experiences with picibanil (OK-432) sclerotherapy for a plunging ranula. Materials and Methods: We retrospectively reviewed 41 patients who have undergone sclerotherapy with picibanil for plunging ranula. Information was collected on age, sex, a number of injection, post-sclerotherapy side effect and outcome of treatment. Results: 17 patients (41.5%) showed a complete response, and 20 patients (48.7%) showed inter-mediate response. No response was seen in 4 patients (9.8%). As a side effect of intracystic OK-432 injection therapy, fever (26.8%) and pain(39.0%) were observed. However, fever and pain disappeared after several days in all cases. Conclusion: The results are showing that OK-432 injection is an effective and safe treatment for plunging ranula.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2008년도 하계학술발표대회 논문집
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• pp.731-736
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• 2008

There was in a building and with the technical advance for a energy saving the secret efficiency of the building improved together and continuously was come. The indoor air environment brought about the deterioration which is remarkable because of it. But time of most the indoor air environmental matter is one in the element which healthily affects biggest in the moderns who lives from the interior space. Today the plan for the air environmental maintenance which dwelling space is appropriate is demanded, is the actual condition where the method of the ventilation control which is energy saving and efficient is necessary. From the research which it sees, number of ventilation 0.7 time of the aeration which is a domestic legal baseline is excessive is judged from the research which sees, The sleep hour assumes it stays most long the hour when, number of ventilation 0 time 0.1 times 0.4 times $CO_2$ consistency measurements and analyzes number of ventilation conclusive escape. And $CO_2$ peak point control leads it decides a data, effective and it talks an energy saving circulation control method and it does to sleep.

• 대한치과기공학회지
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• 제12권1호
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• pp.15-21
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• 1990

This research was to investigate and study on 92 Dental Technicians who had had some experience of working or being employed at dental craft-shops or craft-rooms in Seoul area and had transferred to other types of occupation, with regard to their reasons for changing their profession. For an approach to the study, some questionnaires and interview including 3 aspects of in quiriesmental, economic and social backgrounds-were administered, and major findings are as follows ; 1. The ages in which transferring to other kinds of job happened occurred mostly from 20 to 30(78.26%) an a group of subjects whose ages ranged from 20 to 30 years old. And, with regard to their experience of working or being employed at dental craft-shops or craftrooms, the transfer of their profession to the other kinds mosty happened in a group of subjects(94.56%) whose experience of working in the dental field is less than 4 years. 2. The reason of transfer with reference to the mental background was mostly mattered in a group that expressed "Excessive Work Duties"(34.78%), and most lowly mattered in a group of subjets who had "Certain Relations with Dentists"(8.70%). Thus, it appeared that the biggest reason of transfer by the mental background was, due to the excessive duty work, not to have Sufficient time to be usualized by dental technicians for their own purpose. 3. With reference to the economical background, a group that declared there was "No Wage Standards in Ratio to Their Labor" was the most in the separation rate as shown 45.56%. And, a group suspecting "No Guarantee for Their Living after Retirement" Showed a separation rate, 9.78%. In other words, the reason for transfer was that they did not receive due wage according to their amount of labor. 4. With reference to the social background, a group making a subject for no good working environments or conditions had a separation rate, 41.30%, which was the most among others, and a group with a subject of "The Rarity of Employment because of Excessive Supply of Dental Technicians" had the rate, 10.87%, which was the lowest. This meant that the major cause of transfer by the social background was a phenomenon for dental technicans to escape from unclean working places.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제13권3호
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• pp.338-345
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• 1991

선천성 혹은 술후성 기형으로 발생하는 구개인두 부전증은 구강과 비강사이의 부적절한 폐쇄기능으로 인해 과비음 등의 발음장애를 초래한다. 그 원인으로는 구개파열, 인두비대증, 편도선절제술후의 구개와 인두의 비율 부조화, 구개인두 괄약근의 기형, 구래부전마비, 연구개 결손, 상악골 전진 절단술 등이 있다. 구개인두 부전증의 진단에는 임상적, 방사선학적 검사와 더불어 섬유광학 비내시경을 이용한 구개인두의 기능검사가 강조된다. 수술방법으로는 구개성형술, 인두증강술, 인두성형술, 인두피판술 등이 있다. 근자에는 상부기저형 인두피판술이 널리 사용되고 있는데, Hogan등이 개선시킨 술식에 의하면, 넓고 긴 피판을 얻을 수 있고 피판의 Raw surface를 연구개의 비강측 점막으로 덮을 수 있으며 측방 통로를 조절할 수 있다는 장점이 있다. 이에 저자등은 본인에 내원한 구개인두 부전증 환자 7례에서 상부기저형 인두피판을 이용하여 구강과 비강 사이의 측방 통로를 적절히 조절함으로서 발음을 개선시켜 본 바 양호한 임상성적을 얻었기에 보고하는 바이다.

• Journal of Microbiology and Biotechnology
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• 제33권7호
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• pp.864-874
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• 2023

Natural killer (NK) cell dysfunctions against hepatocellular carcinoma (HCC) in a hypoxic environment. Many solid tumors are present in a hypoxic condition, which changes the effector function of various immune cells. The transcription of hypoxic-inducible factors (HIFs) in cancer cells make it possible to adapt to their hypoxic environment and to escape the immune surveillance of NK cells. Recently, the correlation between the transcription of HIF-1α and pro-inflammatory cytokines has been reported. Interleukin (IL)-6 is higher in cancers with a highly invasive ability, and is closely related to the metastasis of cancers. This study showed that the expression of HIF-1α in HCC cells was associated with the presence of IL-6 in the environment of HCC-NK cells. Blocking of IL-6 by antibody in the HCC-NK interaction changed the production of several cytokines including TGF-β, IL-1, IL-18 and IL-21. Interestingly, in a co-culture of HIF-1α-expressed HCC cells and NK cells, blocking of IL-6 increased the production of IL-21 in their supernatants. In addition, the absence of IL-6 significantly enhanced the cytotoxic ability and the expression of the activating receptors (NKG2D, NKp44, and NKG2C) in NK cells to HIF-1α-expressed HCC cells. These effects might be made by the decreased expression of HIF-1α in HCC cells through the inhibited phosphorylation of STAT3. In conclusion, the absence of IL-6 in the interaction of HIF-1α-expressed HCC cells and NK cells could enhance the antitumor activity of NK cells to HCC cells.

• 의료ㆍ복지 건축 : 한국의료복지건축학회 논문집
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• 제29권3호
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• pp.7-15
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• 2023

Purpose: This study was conducted with the aim of presenting spatial planning directions for evacuation spaces based on an analysis of the performance of horizontal evacuation during the early stages of fire incidents in a geriatric hospital. Methods: Based on a review of previous studies, the research model was designed by establishing occupancy conditions, evacuation, and fire scenarios. The analysis model was developed by considering vulnerable areas in terms of evacuation movement and analyzing the results of evacuation performance. Furthermore, the study analyzed the improvement in evacuation performance by arranging refuge areas. Results: The results of the study are as follows. Firstly, vulnerability spots were identified in terms of evacuation performance by schematizing Required Safe Egress Time, Available Safe Egress Time, and their differences. Secondly, the Required Safe Egress Time in the adjacent public spaces along the escape routes of occupants was found to be higher compared to the Available Safe Egress Time. Thirdly, the results of the correlation analysis between the difference in Available Safe Egress Time and Required Safe Egress Time during the early stages of a fire, as well as their constituent factors, demonstrated that user congestion is a more significant factor in compromising evacuation safety than the physical changes in the fire condition. Fourthly, the analysis of evacuation time was conducted by designating refuge areas where occupants can evacuate within a sufficient timeframe. This led to a decrease in the Required Safe Egress Time. Implications: This study is expected to be used as data on the direction of evacuation space planning to improve the evacuation performance of Geriatric Hospital.

• 한국컴퓨터정보학회논문지
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• 제14권1호
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• pp.9-15
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• 2009

개미 집단 시스템은 조합 최적화 문제를 해결하기 위한 메타 휴리스틱 탐색 방법이다. 기존 개미 집단시스템은 전역갱신과정에서 탐색된 전역 최적 경로에 대해서만 페로몬 갱신을 수행하는데, 전역 최적 경로가 탐색되지 않으면 페로몬 증발만 일어나며 주어진 종료 조건을 만족할 때까지 아무리 많은 반복 수행에도 페로몬 강화가 일어나지 않는다. 본 논문에서 제안된 개선된 개미 집단시스템은 전역 최적 경로의 길이가 주어진 반복 사이클 횟수 동안 더 이상 향상되지 못하면 국부최적에 빠졌다고 평가하고 상태전이 규칙에서 파라미터 감소를 통해 다음 노드를 선택하게 하였다. 이로 인해, 상태전이 규칙에서 파라미터 감소에 의한 다양화 전략으로 탐색하는 결과가 최적 경로 탐색뿐만 아니라, 평균 최적 경로 탐색과 평균 반복횟수의 성능이 우수함을 보여 주었으며, 실험을 통해 그 성능을 평가하였다.

• 해양환경안전학회지
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• 제30권4호
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• pp.317-323
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• 2024

STCW 협약 A-VI에 의거, 승선 필수 증서를 발급받기 위해 소화 과정 최저 훈련 이수를 거치게 되는 공간이 수소화 훈련장이다. 선박 화재의 상황과 유사한 장소에서 발생한 화재 진압 훈련을 위한 실습 장소의 특성상, 재실자의 안전을 보장할 수 있는 운영을 위해 안전성을 수치화하여 평가하고 기준을 수립하는 연구의 필요성이 대두되었다. 화재 안전 평가를 위해 FDS를 기반으로 한 Pyrosim을 활용하여 제연설비 유무에 따른 Case를 설정, vector의 분석을 통한 연기 유동 및 열기에 대한 평가를 수행하였다. 피난 안전평가는 Pathfinder를 통해 허용 피난시간, 총 피난시간을 수치화된 결과로 해석, 비교하여 안전성을 분석하였다. 각 Case에 대한 안전성을 평가함으로 제연설비별 기능의 적정성을 수치, 시각적으로 나타내었으며, 현재 운영 상태는 안전성이 양호한 것으로 평가하였다. 집진설비가 정지한 비상상황은 각 피난시간과 111.2초의 여유시간으로 나타내어 수소화 훈련장의 비상상황에 대한 피난시간의 기준으로 활용할 것을 제시하였다.

• 인간행동과 음악연구
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• 제9권1호
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• pp.37-53
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• 2012

본 연구는 성인 정신보건센터의 성인들을 위한 임상 음악치료에서 음악적 표현 동기의 과정과 패턴을 분석하기 위하여 수행되었다. 참가자들은 27에서 53세 사이의 1년 이상 음악치료를 경험한 8명의 의도 표집된 정신보건센터 회원들이였다. 주요 범주와 분석은 Strauss와 Corbin의 근거이론 방법에 의하여 이루어졌다. 질적 분석 결과 음악치료에서 자발적 음악표현 동기는 치료사와 세션에서 사용되는 노래에 의해 결정된다. 치료사의 친화적 태도, 높은 음악적 역량, 선곡된 노래의 친숙성 그리고 선곡된 노래 가사에 대한 의미부여가 중심현상의 인과적 조건으로 작용한다. 이때 음악치료사에 대한 전문인으로서 인격적, 음악적 신뢰도 정도와 세션에서 사용된 노래의 긍정적 환기가 맥락적 조건으로 작용한다. 음악치료에서 자발적 음악 표현은 공감이라는 중재조건을 통해 현실 도피, 스트레스 해소 그리고 나눔이라는 작용을 일으키며 이것은 무드조절, 희망의 고취 그리고 집단 응집력이라는 결과를 가져왔다. 음악치료에서 참여 동기 유형은 3가지로 내재적 동기, 관계 의존적인 외재적 동기 그리고 회피적 동기유형이 발견되었다.