• 한국지반공학회논문집
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• 제25권4호
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• pp.69-75
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• 2009

본 연구에서는 수평하중을 받는 파일벤트(pile-bent) 구조의 변단면에 따른 거동특성을 분석하기 위하여 beam-column 모델을 적용하여 수평변위 및 모멘트, 부재력(응력)을 단일단면 파일벤트 구조의 수평거동과 비교하였다. 분석결과 지표면에서 변단면 파일벤트 구조의 수평변위량이 동일하중 재하시 단일형 파일벤트 구조의 수평변위량보다 커지는 경향을 보였으나, 동일지반, 동일하중조건의 경우에는 변단면 존재유무에 관계없이 최대휨모멘트 발생위치는 일정한 경향을 보였다. 또한 말뚝재료의 부재력 검토 결과 파일벤트 구조의 변단면 부분에서의 부재력이 최대침모멘트 발생 깊이에서의 부재력보다 큰 것으로 나타났다. 이는 일체형 말뚝의 구조적 특성으로 최대침모멘트 발생위치보다 변단면 부분의 단면축소로 인해 취약해지기 때문에 변단면 발생부분에 대한 보강이 필수적으로 요구됨을 알 수 있었다.

• 생명과학회지
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• 제16권1호
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• pp.58-63
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• 2006

모 조선수리업에 근무하는 1,086명 중 석면에 노출되는 작업공정에 10년 이상 근무한 근로자 118명을 대상으로 단면조사연구를 수행하였다. 연구대상자들에 대해 흥부방사선검사, 폐기능검사와 미국의 산업안전보건청 석면표준, 의학적 감시 프로그램(OSHA asbestos standard, medical surveillance program)에 따라 국내 실정에 맞게 일부 편집한 설문조사를 시행하였고 아울러 이들의 작업장에 대한 작업환경측정 자료도 분석하였다. 흉부방사선검사상 석면관련 폐질환 소견의 유병율은 118명의 근로자중 16명으로 $13.6\%$였다. 흉부방사선검사상 정상군에 비해 석면관련 폐질환 유소견군에서 유의한 요인들은 폐기능검사상 이상소견, 기침, 가래, 호흡기 질환의 과거력, 근무력이었다. 본 연구 결과를 통해 볼 때 폐기능검사 소견상 이상소견, 기침과 가래의 임상증상을 호소하거나 호흡기질환의 과거력, 20년 이상의 근무력이 있는 근로자에 대해서는 석면관련 폐질환의 엄격한 관리가 필요할 것으로 생각된다. 그리고, 본 연구에서 관련성 여부를 완전히 배제할 수 없었던 요인들에 대해서는 향후 광범위한 전향적 연구를 통하여 연관성을 규명하여 석면노출 사업장의 의학적 감시 프로그램에 적극 활용되기를 기대한다.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2013년도 춘계학술대회
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• pp.136-138
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• 2013

현재 해상교통안전시설인 표준등부표의 종류는 10가지이며, 가장 작은 등부표가 4.4m로 대형인 것이 현실이다. 따라서 제작, 교체 및 수리가 용이한 부유형의 소형 등부표를 제안하고자 하였다. 한편 부유형의 경우 환경적 외력에 의한 위치 신뢰도가 떨어지며, 특히 유실 등의 사고에 대비하기 위한 안정성 검토가 필요하다. 이 논문에서는 새로운 등부표의 운동성(Heave, Sway, Pitch)을 상용프로그램을 사용하여 Encounter Frequency별 분석하고, 2차원 경계요소법(Boundary Element Method, BEM)을 이용하여 부유체의 단면형상에 따른 유체력을 수치시뮬레이션하였다.

• 한국자동차공학회논문집
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• 제20권4호
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• pp.109-118
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• 2012

Large number of part design for aircraft and automobile is preceded by functional or sectional design groups for efficiency. However, interferences and gaps can be found when the parts and sub-assemblies by those design groups are to be assembled. These interferences and gaps cause design changes and additional repair processes. While interference problem has been resolved by digital mockup and concurrent engineering methodology, gap problem has been covered by temporary treatment of filling gap with sealant. This kind of fast fix causes fatal problem of leakage when the gap is too big for filling or the treatment gets old. With this research, we have developed a program to find the gap automatically among parts of assembly so that users can find them to correct their design before manufacturing stage. By using decomposition model representation method, the developed program can search the gap among complex car body parts to be visualized with volumetric information. It can also define the boundary between the gap and exterior empty space automatically. Though we have proved the efficiency of the developed program by applying to automobile assembly, application of the program is not limited to car body only, but also can be extended to aircraft and ship design of large number of parts.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제41권
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• pp.5.1-5.5
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• 2019

Background: The present study aimed to determine whether laypeople and professionals rate the facial appearance of individuals with repaired complete unilateral or bilateral cleft lip and palate (UCLP, BCLP) similarly based on viewing full facial images. Methods: The study followed a cross-sectional analytical design where five young patients aged 10 to 14 years, who had completed all stages of their unilateral or bilateral cleft lip and palate treatment (bilateral: three, unilateral: two), were evaluated by two groups. The assessment was done by laypeople and 97 qualified professionals (33 orthodontists, 32 plastic surgeons, and 32 oral and maxillofacial surgeons). Professionals were not involved in any stage of the patients' treatment. Results: The facial appearance assessment of the professional groups on different facial aesthetics was significantly lower than that of laypeople, and they had higher perceived need for further treatment. On the other hand, laypeople had higher aesthetic ratings and lower perceived need for further treatment. Differences were also observed between the assessments of the professional groups. Participants who had lower aesthetic assessments of the repair tended to report a higher influence of cleft lip and palate on social activities and professional life. Conclusion: Differences in perception exist between healthcare professionals and laypeople. The discrepancies between the professional groups could be attributed to different treatment modalities and protocols.

• Archives of Plastic Surgery
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• 제33권1호
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• pp.75-79
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• 2006

The upper and lower lateral cartilages provide the key to the lower cartilaginous portion of the nose. Lifting the cartilages is essential procedure for correction of unilateral cleft lip nose deformity. After correction of cleft lip nose deformity, authors used acoustic rhinometry (AR) to compare the lower nasal cavity of cleft side with non-cleft side. AR is a well known new, non-invasive diagnostic technique in which nasal geometry is assessed by means of acoustic reflection. From June 1996 to January 2004, we performed acoustic rhinometric analysis after correction of unilateral cleft lip nose deformity. This study involved 40 children of age ranged from 3 months to 8 years. Subjects were divided into the group of incomplete unilateral cleft lip nose deformity(20 subjects), and the group of complete unilateral cleft lip nose deformity(20 subjects). Results show that lower nasal cavity volume between non-cleft side and cleft side has no difference, and better results were obtained when nasal molding prong was applied at cleft side nostril. The results between incomplete type and complete type have no significant difference. In conclusion, AR is an effective method to calibrate cross sectional area and nasal cavity volume of unilateral cleft lip nose deformity, and furthermore effective in comparing the volume of cleft side with non-cleft side after unilateral cleft lip nose deformity correction with lifting the lower lateral cartilages to the upper lateral cartilages.

• Journal of the Korean Wood Science and Technology
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• 제44권4호
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• pp.515-525
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• 2016

The Palsangjeon Pagoda is a five-story wooden building in the Beopjusa Temple area in the Songnisan national park in Chungcheongbuk-do, Korea. According to historical records, it was constructed in either AD 1605 or AD 1626. To specify the construction year more precisely, we took 41 wood samples for tree-ring analysis during repair actions in 2013; 28 from red pine (Pinus densiflora S. et Z.), 12 from oak (Quercus spp.), and 1 from fir (Abies spp.). The tree-ring boundaries became clearly visible by smoothing their cross-sectional surface and the tree-ring widths were measured under a stereo microscope. All tree-ring series were compared with each other to establish mean chronologies, which we then compared with local master chronologies established using tree rings collected from wooden elements of the Daeungjeon Hall which is the main building in the Beopjusa Temple area. As a result, it was verified that the red pines were felled in AD 1624 and in AD 1851. Moreover, it was verified that the oaks were also felled in AD 1624 based on cross-dating with the red pine chronology. We concluded that the Palsangjeon Wooden Pagoda was constructed in AD 1626, as mentioned in the historical record (Daeungdaekwangmyeongjeonbulsangki, 1630) and the letters on a purlin on the $4^{th}$ story, using oak and red pine felled in AD 1624 and repaired later on using red pine felled in AD 1851.

• 한국안전학회지
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• 제25권6호
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• pp.86-91
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• 2010

The purpose of this study is to analyze the damage patterns and metal structure of 3 phase mold transformers collected from places where accidents have occurred. Compared to an oil-immersed transformer, a mold transformer has the advantage of requiring a smaller installation area and can be kept clean, while its disadvantages include the fact that abnormal symptoms of an accident are difficult to discover and its repair is impossible. The capacity of the mold transformers collected from places where accidents have occurred was 200kVA with primary voltages being F23,900V, R22,900V, 21,900V, 20,900V, 19,900V, etc., as well as secondary voltages being 380V, 220V, etc. It was found from the analysis on the diffusion of combustion in the damaged mold transformers that fire occurred first inside the U-phase primary winding and that carbonization and heat were diffused to V-phase and W-phase in V-pattern. In addition, from the analysis on the cross-sectional structure of the metal of the melted high voltage winding using a metallurgical microscope, it was found that the boundary surface, voids, and columnar structure were formed when an interlayer short-circuit had occurred Therefore, even though it is not possible to find the cause for the occurrence of an interlayer short-circuit at the inner side of the primary winding, it is thought that, due to the thermal energy generated when the short-circuit occurred, the heat source was diffused to the upper side and outside, causing a secondary accident.