LED 광원 크기에 따른 자유 형상 렌즈의 조명 성능 변화와 공차 특성

양재석,김대찬,오범환,박세근,유일현,이승걸,Yang, Jae-Suk,Kim, Dae-Chan,O, Beom-Hoan,Park, Se-Geun,You, Il Hyun,Lee, Seung Gol 한국광학회 2013 한국광학회지 Vol.24 No.1

본 논문에서는 점광원을 기준으로 설계된 자유 형상 렌즈(freeform lens)의 조명 성능과 LED 광원 크기와의 관계 및 공차 특성을 살펴보았다. 비교를 위해 발산 조명 모델(divergent illumination model)을 적용한 두 가지 렌즈와 중첩 조명 모델(overlapped illumination model)을 적용한 한가지 렌즈를 설계하였다. LED 광원이 커짐에 따라 평균 조도에 비해 조도 균일도가 상대적으로 크게 감소하였으며, 정렬 오차에 의한 성능 저하는 거의 발생하지 않았다. 하지만 LED 광원의 방출 특성 변화는 LED 광원 크기에 관계없이 조명 성능에 영향을 미치는 것으로 확인하였다. 발산 조명 모델로 설계된 렌즈가 전반적으로 우수한 성능을 보였지만, LED 방출 특성 변화에 대해서는 중첩 조명 모델로 설계된 렌즈의 성능이 상대적으로 적게 변화함을 알 수 있었다. In this paper, the illumination performances of three freeform lenses optimally designed for a point source were investigated for several LEDs with different source sizes, and also the tolerance characteristics of the lenses were analyzed. For comparison, two lenses with different sizes were designed with a divergent illumination model, and the last one was done with an overlapped illumination model. As the LED source size increased, the illuminance uniformity decreased more strongly, and the influence of a source misalignment on illumination performance became insignificant. However, the variation of LED radiation characteristics had strong effect on the illumination performance, irrespective of LED source size. Even though the lens based on a divergent illumination model showed superior performance compared to the lens based on an overlapped illumination model, the latter was less sensitive to the variation of LED radiation characteristics.

균일 LED조명을 위한 자유형상 2차 광학계 설계 및 공차 분석

양재석(Jae Suk Yang),박혜민(Hae Min Park),김대찬(Dae Chan Kim),오범환(Beom Hoan O),이승걸(Seung Gol Lee) 한국조명·전기설비학회 2011 한국조명·전기설비학회 학술대회논문집 Vol.2011 No.11

A freeform lens was optimally designed for achieving an uniform illumination and also its tolerance analysis was performed by considering alignement and fabrication errores. Divergent model was chosen for establishing the ray-arriving point relation for uniform illumination, and the differential equation for the lens shape was numerically solved. The illuminance distribution on the target area was calculated with LightTools™ and the uniformity was extracted from the distribution. From the tolerance analysis, it was confirmed that the alignment error could give harmful effect on the performance.

노인맞춤돌봄서비스 서비스 질 강화 연구 : 생활지원사 직무교육의 효과와 조직지원인식의 매개효과를 중심으로

양재석(Yang, Jae Suk),김근홍(Kim, Keun Hong) 한국사례관리학회 2021 사례관리연구 Vol.12 No.1

본 연구는 노인맞춤돌봄서비스의 서비스 질 향상을 위하여 핵심 수행인력인 생활지원사에 대한 직무교육과 조직지원인식 그리고 서비스 질의 상관관계를 실증하는데 있다. 연구 검증을 위해 직무교육 효과와 조직지원인식의 매개효과를 분석하여 도입 초기에 있는 사업의 서비스 질 향상을 위한 정책 방향을 모색하였다. 본 연구는 서울시 및 경기도 노인맞춤돌봄서비스 수행기관에서 근무하고 있는 생활지원사를 대상으로 설문조사 하였다. 연구 분석은 536명의 자료를 수집하여 빈도분석 및 차이분석, 상관관계분석, 구조모형 분석을 실시하였다. 분석 결과 직무교육의 효과와 조직지원인식이 높을수록 서비스 질이 높음을 확인하였다. 또한 생활지원사의 직무교육과 조직지원인식, 서비스 질은 유의미한 상관관계가 나타났으며, 조직지원인식의 매개효과 역시 검증 되었다. 이를 바탕으로 본 연구는 첫째, 노인맞춤돌봄서비스의 질을 높이기 위한 직무교육의 질적․양적 강화, 둘째, 수행기관의 생활지원사 지원체계 강화 및 표준화와 처우개선, 셋째, 생활지원사의 상사 수퍼비전과 동료 간 상호 피드백을 원활하게 하기 위한 의사소통 시스템 구축 등에 따른 정책 방향성을 제시하였다. The following study aims to demonstrate the correlation between job training, perceived organization support and quality of service for care supporter, who are the core manpower, in order to improve the quality of senior personalized care service. To achieve this, the mediating effects of job training and the perceived organization support were analyzed and the policy direction for improving the quality service of the business in the early stages were sought. The study surveyed care supporters working at executing organizations for senior personalized care service in Seoul and Gyeonggi province and the care supporter. For the study analysis, data were collected from 536 individuals and conducted frequency analysis, difference analysis, correlation analysis and structural model analysis. The analysis confirmed that the higher the effectiveness of job training and perceived organization support, the higher the quality of service. In addition, care supporter’s job training, perceived organization support, and the quality of service showed a significant correlation and the mediating effect of perceived organization support was also verified. Based on this, this study proposed directions for first, the strengthened qualitative and quantitative job training to improve the quality of senior personalized care service, second, strengthened and standardized executing organization’s ‘care supporter’ supporting system and enhanced treatment, and third, provided policy directions for establishing a communication system to facilitate the exchange of mutual feedbacks between care supporter and his supervisor or colleagues.

항에리트로포에틴 (Anti-erythropoietin) 항체에 의한 진성 적혈구계 무형성증 (Pure Red Cell Aplasia) 2예

양재석 ( Jae Seok Yang ),이정은 ( Jung Eun Lee ),박동준 ( Dong Jun Park ),성은영 ( Eun Young Seong ),주권욱 ( Kwon Wook Joo ),안규리 ( Cu Rie Ahn ),한진석 ( Jin Suk Han ),김성권 ( Suhng Gwon Kim ),조한익 ( Han Ik Cho ),이정상 ( Ju 대한신장학회 2004 Kidney Research and Clinical Practice Vol.23 No.5

초미세결정립 Fe73.5Cu₁Nb₃Si16.5B6 합금의 뫼스바우어 효과 연구

김재경(Jae Gyeung Kim),신영남(Young Nam Shin),양재석(Jae Suk Yang) 한국자기학회 1995 韓國磁氣學會誌 Vol.5 No.5

Amorphous Fe_(73.5)Cu₁Nb₃Si_(16.5)B_6 ribbons were annealed for different time at 500℃ and 552℃, just before and after the exothermic reaction in DSC curve. The development of nanocrystalline phase was investigated by means of Mossbauer spectroscopy. The crystalline phase consists mainly of DO₃ Fe-Si. Though slight in amount (5 %), another ferromagnetic phase which could be presumed t-Fe₃B was detected Si content of DO₃ Fe-Si, Si/(Fe+SO, was 0.218 under the heat treatment at 500℃ for 60 min and 0.222 at 552℃ for 10 min. Since then both of those values decreased with time until 120 min and finally these two values remained constant at 0.210. The variation in Si content with annealing time results in the variation in the hyperfine field and the isomer shift. The increase in the mean hyperfine fields and the decrease in the mean isomer shifts of Fe-Si are caused by the increase in Si content. The volume fractions of residual amorphous phase rapidly decrease during the early stage of annealing and come nearer to saturation after 120 min both at 500℃ and 552℃. The decrease in the mean hyperfine field of residual amorphous, in spite of slight changes in the volume fractions of Fe-Si and of residual amorphous after 120 min, is caused by the increase in the content of Nb and B in residual amorphous phase. The saturated volume fraction of the crystalline phase was 81 % for 500℃ (180 min) and 77 % for 552℃ (960 min), different from expectation.

정부 에너지 R&D 투자가 수혜기업의 매출에 미치는 영향 분석

이정우(Jungwoo Lee),양재석(Jae-Suk Yang) 한국신재생에너지학회 2017 신재생에너지 Vol.13 No.1

Since the late 2000s, the Korean government’s energy policy has begun to re-examine the energy industry as a new growth engine for the nation, furthering its goal of stabilizing supply and demand. The government has steadily increased R&D investment in the energy sector by promoting “low-carbon green growth” with the paradigm of national development. The aim of this study was to determine if government R&D investment has an effect on the sales growth of beneficiaries in the energy industry. In addition, this study analyzed how the effects of government R&D investments differ in renewables, electricity, and the nuclear program. The results showed that the government R&D investment does not necessarily guarantee an improvement in sales growth of the beneficiary company, but is significant only in the renewable energy sector. This study concludes that there is a need to diversify the investment types according to the market and technology maturity.

출연(연) 연구인력 개인평가제도 분석 및 개선

이석준(Seok-Jun Lee),양재석(Jae-Suk Yang),김중현(Jung-Hyeon Kim) 한국기술혁신학회 2019 한국기술혁신학회 학술대회 발표논문집 Vol.2019 No.11

국가연구개발투자 확대정책을 통해 연구 성과가 양적으로 크게 성장하였으나 질적 수준은 선진국 대비 미흡하다. 최근 10년간 GDP 대비 국가연구개발 비중은 4.03%로 세계 2위권(’17)을 차지하며 양적 성과는 크게 증가(미래부, ’15 OECD, "13년)했다. 그러나 논문 피인용 횟수는 평균 대비 낮고, 기술무역 수지는 OECD 34개국 최하위권에 해당된다. 이에 따라 정부는 연구인력의 개인평가제도를 질적성과 중심으로 개선을 하고자 노력하고 있다. R&D평가방향 전환에 따라 우수성과 창출과 기관성과 달성을 뒷받침할 수 있도록 개인평가도 질적 성과지표 중심으로 개선을 추진중이나 여전히 기관별로 개인평가 시 일부 양적지표를 활용하고 있어 정부 정책목표 달성을 유도하는데 한계가 발생하고 있다. 이에, 출연(연) 연구 현장의 질적 성과 중심 개인평가제도의 효과적 정착을 위한 연구인력 개인평가제도 개선방안 마련 및 확대가 필요하다. 본 논문은 25개 과학기술분야 정부출연연구기관의 개인평가 제도를 분석하고, 개인평가의 질적성과 중심 평가로 개선을 위한 방향을 제시하는 것을 목표로 한다. Although research achievements have grown significantly in quantity through the state R&D investment expansion policy, the quality level is not as good as that of advanced countries. Over the past 10 years, the proportion of national R&D to GDP was 4.03 percent, accounting for the world"s second largest ("17), and quantitative performance has increased significantly. However, the number of paper employees is lower than average, and the balance of technology trade is among the lowest in 34 OECD countries. Accordingly, the government is making efforts to improve the personal evaluation system of researchers based on their quality. In order to support excellence and achievement of institutional performance in the R&D evaluation direction, individual assessment is also pushing for improvement based on qualitative performance indicators, but still utilizing some quantitative indicators for individual assessment by institutions, which is limiting the achievement of government policy goals. Therefore, it is necessary to prepare and expand measures to improve the individual assessment system of research personnel for the effective settlement of the individual assessment system centered on qualitative performance at the research site. This paper aims to analyze the personal evaluation system of the 25 government-funded research institutes science and technology, and present directions for improvement with the qualitative and central evaluation of individual assessments.

초미세결정립 Fe73.5Cu₁Nb₃Si16.5B6 합금의 Mossbauer 효과 연구

신영남(Young Nam Shin),김재경(Jae Gyeung Kim),양재석(Jae Suk Yang),조익한(Ick Han Cho),강신규(Sin Giu Kang) 한국자기학회 1994 韓國磁氣學會誌 Vol.4 No.1

The crystallization behavior of the amorphous Fe_(73.5)Cu₁Nb₃Si_(16.5)B_6 alloy with isothermal annealing at 552 ℃ was studied by Mossbauer spectroscopy. The amorphous phase was revealed to coexist together with DO₃-FeSi nanocrystalline and Cu-duster in annealed alloys by Mossbauer spectrum analysis. At the early stage of crystallization, Si content of FeSi is high due to the creation of Cu-cluster, and decreases with annealing until 60 minutes, which results in the increase in the mean hyperfine field of FeSi, and thereafter keeps constant. After 60 minutes, the decrease in the mean hyperfine field of the residual amorphous, in spite of a slight change in the volume fraction of the FeSi and the residual amorphous, is caused by the increase in the content of Nb and B in residual amorphous phase. Both directions of the hyperfine field, those of the FeSi and the residual amorphous, become randomly oriented in about 60 minutes. For FeSi and Cu-duster, the Avrami exponents are 0.51 and 0.65, the activation energies are 2.35 eV and 2.44 eV, and the incubation times are 2.4 minutes and 0.8 minutes respectively. Earlier formation of Cu-duster than that of FeSi is coincidence with the fact that Cu atom promotes the nucleation of the FeSi.

상호선택 및 학습모델에서 노이즈의 역할

권용하(Yongha Kwon),안정수(Jungsoo Ahn),양재석(Jae-Suk Yang),김지현(Ji-hyun Kim) 연세대학교 동서문제연구원 2016 동서연구 Vol.28 No.2

조직학습과 탐색 연구에서 적당한 수준의 노이즈는 조직에게 변화를 제공함으로서 성과에 긍정적인 영향을 미칠 수 있음이 밝혀졌다. 우리는 기존의 관련 연구에서 조직 구조에 대한 검토가 지나치게 간소화되어 왔음에 주목하여, 본 연구에서 적당한 수준의 노이즈가 상호 선택 및 학습 모델의 위치에 따라 그 역할이 달라질수 있음을 제시한다. 우리는 James G. March (1991)의 학습 모델을 확장하여, 조직의 코드와 개인이 상호 선택, 학습하는 모델에서 노이즈의 역할을 탐구한다. 본 연구를 통해 학습 단계에서의 노이즈는 성과에 긍정적이나, 선택 단계에서의 노이즈는 부정적임을 밝혀냈으며, 이 결과는 노이즈의 역할이 다양한 조직 구조 에서 재검토될 필요가 있음을 보여준다. In organizational learning and search literature, conventional wisdom holds that a moderate degree of noise helps organizations improve their performance by introducing more variation. We would like to note, however, that portrayals of most organizational structures in this line of inquiry are over simplified. We contribute to this topic by suggesting that the beneficial role of moderate noise is dependent on its relational presence in a mutual selection and learning system. By extending March’s (1991) mutual learning model, we examine the role of noise in an organization as an adaptive system, where both the organizational code and individuals can select and learn from others. We demonstrate that while a small amount of noise on the learning stage is beneficial, noise on the selection stage monotonically decreases performance. Our results indicate a need for re-examination of the role of noise in various organizational settings and structures.

지속성 외래 복막투석 환자에서 복막염의 발병 양상 단일 임상 기관 연구

안규리(Cu Rie Ahn),한진석(Jin Suk Han),김성권(Suhng Gwon Kim),이정상(Jung Sang Lee),오윤규(Yoon Kyu Oh),김현리(Hyun Lee Kim),정우경(Woo Kyung Chung),오국환(Kwook Whan Oh),양재석(Jae Suk Yang),김세중(Se Jung Kim),이경이(Kyung Ey Lee) 대한신장학회 2001 Kidney Research and Clinical Practice Vol.20 No.4

Peritonitis remains the leading cause of the patient dropout in CAPD in many developing countries. In Korea, 71% of CAPD patients dropout is caused by peritonitis. To elucidate an adequate guideline for treating peritonitis in our country, we analyzed clinical and bacteriologic profiles of peritonitis(1995. l. 1- 1999. 12 31). Two hundred and twenty eight episodes of peritonitis were developed in 127/247 patients. The incidence of peritonitis was 0.41/patient-year in general, which was decreased to 0.24/patient-year in 1999. The incidence of causative organisms were as follows: 82(36.0%) by Gram positive organisms, 38 (16.2%) by gram negative organisms, 16 cases(7.0%) by mixed organsisms, and 5 cases(2.2%) by fungus. During study period, the incidence of peritonitis by gram positive organsism was decreased while the incidence of peritonitis by gram negative organism was not changed. Recurrent infection/relapse was noted in 58 patients(45%). Peritonitis were eradicated only in 66% of the cases by initial antibiotics(cefazolin+aminoglycoside); and another 17% responded by second line antibiotics. Peritoneal catheters were removed in 38 episodes(16.7%). Patients with exit infection were more frequent in removal of catheter. Risk factor analysis was performed in 146 patients, who were newly started CAPD. There were 60 initial episodes of peritonitis(mean duration of follow up was 16.7 patient months). Sixty-five percent were free of peritonitis at the end of first year, 54% at the end of second year and 45% at the end of third year (Kaplan-Meier). Factors such as age, sex, underlying DM, were not risk factor for CAPD peritonitis. In conclusion, we observed that the incidence of peritonitis decreased every year. It was revealed however that only 66% of peritonitis can be successfully treated by first line antibiotics. Second line antibiotics such as ceftazidime may need to be introduced in early phase of CAPD peritonitis. Up to one third of patients had recurrent infection/relapse, which raised the incidence of peritonitis. Continuing education as well as better exit care is needed to improve technical survival of CAPD patients in Korea.