컴퓨터 작업으로 인한 눈 피로의 객관적 평가 방법

서영우,김균형,강수연,김성우,오재령,김효명,송종석,Young-Woo Suh,Kyun-Hyung Kim,Su-Yeon Kang,Seoung Woo Kim,Jae Ryung Oh,Hyo-Myung Kim,Jong-Suk Song 대한안과학회 2010 대한안과학회지 Vol.51 No.10

Purpose: To develop methods for the objective measurement of ocular fatigue. Methods: Fifteen patients were enrolled in the present study. Subjects performed visual tasks on a computer for one hour. A survey of ocular fatigue was conducted with a questionnaire. Tear break-up time, blinking rate, ocular protection index, conjunctival injection, maximal blinking interval, temperature of the ocular surface, and visual evoked potential were evaluated before and immediately after the task. Surface electromyography of the orbicularis oculi muscle was performed before and during the task. Results: The survey showed increases in subjective ocular fatigue in all subjects. Tear break-up time, ocular protection index and maximal blinking interval decreased, while temperature of the ocular surface increased after the task. Conjunctival injection showed a tendency to increase. Electromyography, and visual evoked potential did not change significantly. Conclusions: In the present study, tear break-up time, ocular protection index, maximal blinking interval, and temperature of the ocular surface changed as ocular fatigue increased. Therefore, these measures can be objectively used for the evaluation of ocular fatigue. J Korean Ophthalmol Soc 2010;51(10):1327-1332

병원외 심정지 후 자발순환회복 환자의 관상동맥조영술 결과

서영우,장태창,이경원 대한응급의학회 2011 대한응급의학회지 Vol.22 No.5

Purpose: Coronary artery disease is the most common cause of out-of-hospital cardiac arrest (OHCA). Primary percutaneous coronary intervention (PCI) is currently the most effective reperfusion strategy in acute myocardial infarction. The decision to perform PCI in an unconscious resuscitated OHCA patient is challenging because of uncertainty of the clinical course, status of the coronary artery and prognosis. The study evaluated clinical characteristics,angiographic findings and results of OHCA patients who were successfully resuscitated and underwent PCI. Methods: A retrospective study was performed from January, 2008 to December, 2010. Thirty four OHCA patients who successfully resuscitated and followed by PCI were enrolled. They were divided into significant and nonsignificant coronary artery group. Significant coronary artery group (n=23) was subdivided into survival and mortality subgroup. Results: Twenty three of the 34 patients had significant coronary disease on coronary angiography. There was no significant difference between the two groups in clinical and electrocardiography (ECG) findings based on age, sex,presence of chest pain, initial ECG, and ECG after return of spontaneous circulation (ROSC). The significant coronary artery group displayed higher creatine kinase-MB and troponin-I levels, and more common presence of ventricular fibrillation (VF) prior to PCI. The survival subgroup showed a lower number of significant stenotic coronary arteries, better neurologic finding prior to PCI and lower levels of cardiac biomarkers such as creatine kinase-MB and troponin-I. Conclusion: PCI after ROSC in OHCA patients with presumed ischemic cardiac etiology may be reasonable, even in the absence of a definite clinical and ECG finding. The presence of VF or serial cardiac biomarkers is helpful in deciding whether to perform PCI.

Analysis of the Effects of Medial Rectus Muscle Resection for Recurrent Exotropia

서영우,Il-Hun Seo,조윤애,김승현 대한안과학회 2011 Korean Journal of Ophthalmology Vol.25 No.5

Purpose: The purpose of this paper is to investigate how much correction is obtained per millimeter of medial rectus (MR) resection for recurrent exotropia after bilateral lateral rectus (BLR) recession, and to determine the difference in the effects between unilateral and bilateral resection, and the influence of previous lateral rectus (LR) recession on the effects of MR resection. Methods: A total of 59 patients who had undergone MR resection after BLR recession were included in this study. The unilateral group consisted of 38 patients and bilateral group, 21 patients. Thirty patients in the unilateral group were divided into two groups: patients who had undergone previous LR recession of 7 mm or greater (21patients) and less than 7 mm (9 patients). Main outcome measures were average deviation corrected per millimeter of MR resection at 1 month postoperative. Results: The average effect of MR resection was 4.2 prism diopters (PD, 2.0 to 6.7 PD)/mm. The average effect in the unilateral group was 4.2 PD/mm and 4.1 PD/mm in the bilateral group. There was no significant difference between groups (p = 0.60). The average effect in the recession 7 mm or greater group was 4.0 PD/mm, and the average effect in the recession less than 7 mm group was 4.2 PD/mm (p = 0.698). Conclusions: The effect of MR resection per millimeter was variable. The laterality and previous amount of LR recession did not influence the effect of MR resection. These variable outcomes dictate that caution be exercised when MR resection is performed for recurrent exotropia.

추간판 장애 환자의 의료이용 현황 및 특성 –경추질환을 중심으로-

서영우,박초열 한국의료정보교육협회 2021 보건의료생명과학논문지 Vol.9 No.1

본 연구는 건강보험심사평가원 2010~2018년까지 표본자료 DB에서 설정한 의료서비스를 이용대상자 중 경추간판장애를 주상병으로 1회 이상 요양급여를 받은 환자를 대상으로 하였다. 경추간판장애 환자는 9개년 모두 성별로는 여성이, 연령별로는 50~59세에서 가장 많았다. 의료기관 종별 이용 행태는 남성과 여성 모두, 모든 연령대에서 의원 이용자가 가장 많았다. 질환별 입원일수는 M50.0(척수병증을 동반한 경추간판장애)은 종합병원과 병원, 의원에서 가장 길었으며, M50.1(신경뿌리병증을 동반한 경추간판장애)은 상급종합병원과 한방의료기관에서 가장 길었다. 외래 진료일수는 M50.0(척수병증을 동반한 경추간판장애)은 상급종합병원과 종합병원, 병원, 의원에서 가장 길었으며, M50.8(기타 경추간판장애)은 보건기관과 한방의료기관에서 가장 길었다. 경추간판장애 환자의 수술은 남성이 많았으며, 40~49세, 50~59세에서 높았다. 2010년 대비 2018년의 수술 추이는 남성, 여성, 전체 환자 모두 감소 추세를 보였다.

지상파 UHD 방송 부가서비스 동향 및 전망

서영우,전성호 한국방송·미디어공학회 2020 한국방송미디어공학회 학술발표대회 논문집 Vol.2020 No.7

지상파 방송 모바일 서비스 기술동향 및 전망

서영우 한국방송·미디어공학회 2023 한국방송미디어공학회 학술발표대회 논문집 Vol.2023 No.6

다문화를 중심으로 한 사회적기업의 성공 가능성과 지속 요인에 관한 연구

서영우 다문화아동청소년연구원 2017 다문화아동청소년연구 Vol.2 No.1

본 연구에서는 다문화를 중심으로 한 사회적기업이 추구하는 성과에 이르기 위 해서 필요한 성공요인들을 선행연구를 통해 분석하고, 이중 경영역량 요인, 사회 적기업가정신 요인, 사업 환경에 초점을 맞추어 이 요인들이 다문화 중심의 사회 적기업의 성과에 어떤 영향을 미치는지 문헌연구와 설문을 통한 분석방법으로 진 행하였다. 본 연구의 결과를 요약하면 다음과 같다. 사회적기업을 운영하는 경영 진의 다문화의 인식정도에 따라 앞으로의 다문화를 중심으로 한 사회적기업의 성 공의 여부가 많이 결정이 된다. 첫째, 경영역량이 우수할수록 경제적 성과가 우수할수록 지속능성이 높게 나타났다. 둘째, 경영역량이 지속가능성에 미치 는 영향에 대해 사회적 성과의 매개효과를 검증한 결과 매개효과가 없는 것 으로 나타났다. 셋째, 사업 환경이 좋을수록 경제적 성과가 높을수록 지속가 능성이 높게 나타났다.따라서 다문화중심의 사회적기업이 성장을 하기 위해 서는 경영진의 기업가 정신의 향상과 환경제공을 보다 신경써서 해야할 것 이다. 이러한 점이 본 연구를 중심으로 개선이 되어 성과가 나올 수 있는 다문화 중심의 사회적 기업이 확대되어야 할 것이다. This study, we analyze the success factors needed to achieve the achievement pursued by the multicultural society, and focus on the factors of managerial competence, social entrepreneurship, and business environment. The results of this study are as follows. The results of this study are summarized as follows. According to the degree of recognition of multiculturalism by the executives who run the social enterprise, the success of the social enterprise centering on the future multiculturalism is highly determined. First, the better the managerial capacity, the better the economic performance. Second, the mediating effects of social performance on the sustainability of the management competency were not mediated. Third, the better the business environment and the higher the economic performance, the higher the sustainability. Therefore, in order for multicultural social enterprises to grow, it is necessary to pay more attention to improving entrepreneurship and providing environment to the management. This study should be centered on this study and it should be expanded to multicultural social enterprises that can produce results.

방송 콘텐츠와 실감 미디어 기술

서영우,Seo, Yeong-U 한국정보처리학회 2018 정보처리학회지 Vol.25 No.2

Improving the Corrosion Resistance of AISI 316L Steel for Semiconductor Piping by Controlled Delta-Ferrite Content

서영우,김찬양,서보경,정원섭 대한금속·재료학회 2022 대한금속·재료학회지 Vol.60 No.1

This study evaluated changes in delta-ferrite content depending on the preheating of AISI 316L stainless steel. We also determined the reasons for the variation in delta-ferrite content, which affects corrosion resistance. Changes in delta-ferrite content after preheating was confirmed using a Feritscope, and the microstructure was analyzed using optical microscopy (OM). We found that the delta-ferrite microstructure size decreased when preheating time was increased at 1295 oC, and that the delta-ferrite content could be controlled through preheating. Potentiodynamic polarization test were carried out in NaCl (0.5 M) + H2SO4 (0.5 M) solution, and it was found that higher delta-ferrite content resulted in less corrosion potential and passive potential. To determine the cause, an analysis was conducted using energy-dispersive spectroscopy (EDS), which confirmed that higher delta-ferrite content led to weaker corrosion resistance, due to Cr degradation at the delta-ferrite and austenite boundaries. The degradation of Cr on the boundaries between austenite and delta-ferrite can be explained by the difference in the diffusion coefficient of Cr in the ferrite and austenite. A scanning electron microscopy (SEM) analysis of material used for actual semiconductor piping confirmed that corrosion begins at the delta-ferrite and austenite boundaries. These results confirm the need to control delta-ferrite content in AISI 316L stainless steel used for semiconductor piping.

이트리아 안정화 지르코니아 소결체의 특성에 Al2O3가 미치는 영향

서영우,최시영 경북대학교 전자기술연구소 1989 電子技術硏究誌 Vol.10 No.1

Yttria-stabilized sirconia were investigated with respect to the amount of Al₂O₃, addition in the range of 0.5-2 mole% to the base composition of 8 mole% yttria-zirconia. Sintered density increased with increasing Al₂O₃ concentration up to 0.5 mole % but decreased at 1.0 mole % Al₂O₃. Grain size abruptly increased with addition of Al₂O₃ content but decreased at 1.0 mole% Al₂O₃. Vickers hardness is proportional to sintered density. Electrical conductivity of the specimen contained 0.5 mole% Al₂O₃ exhibited a maximum conductivity. From the above results, Yttria stabilized zirconia contained 0.5 mole% Al₂O₃ suit for oxygen sensor.