Light-extraction efficiency control in AlGaN-based deep-ultraviolet flip-chip light-emitting diodes: a comparison to InGaN-based visible flip-chip light-emitting diodes.

Lee, Keon Hwa,Park, Hyun Jung,Kim, Seung Hwan,Asadirad, Mojtaba,Moon, Yong-Tae,Kwak, Joon Seop,Ryou, Jae-Hyun Optical Society of America 2015 Optics express Vol.23 No.16

<P>We study light-extraction efficiency (LEE) of AlGaN-based deep-ultraviolet light-emitting diodes (DUV-LEDs) using flip-chip (FC) devices with varied thickness in remaining sapphire substrate by experimental output power measurement and computational methods using 3-dimensional finite-difference time-domain (3D-FDTD) and Monte Carlo ray-tracing simulations. Light-output power of DUV-FCLEDs compared at a current of 20 mA increases with thicker sapphire, showing higher LEE for an LED with 250-관m-thick sapphire by ~39% than that with 100-관m-thick sapphire. In contrast, LEEs of visible FCLEDs show only marginal improvement with increasing sapphire thickness, that is, ~6% improvement for an LED with 250-관m-thick sapphire. 3D-FDTD simulation reveals a mechanism of enhanced light extraction with various sidewall roughness and thickness in sapphire substrates. Ray tracing simulation examines the light propagation behavior of DUV-FCLED structures. The enhanced output power and higher LEE strongly depends on the sidewall roughness of the sapphire substrate rather than thickness itself. The thickness starts playing a role only when the sapphire sidewalls become rough. The roughened surface of sapphire sidewall during chip-separation process is critical for TM-polarized photons from AlGaN quantum wells to escape in lateral directions before they are absorbed by p-GaN and Au-metal. Furthermore, the ray tracing results show a reasonably good agreement with the experimental result of the LEE.</P>

암환자가 지각한 사회적지지, 희망과 삶의 질과의 관계

태영숙,강은실,이명화,박금자 고신대학교 전인간호과학연구소 2002 전인간호과학연구 학술모음집 Vol.- No.-

The Relationship among Percieved Social Support, Hope and Quality of Life of Cancer Patients Tae, Young Sook. Kong, Eun Sil. Lee, Myung Hwa. Park, Geum Ja The purpose of this study was to investigate the relationship among percieved social support, hope and Quality of life of the cancer patients and to gain the baseline data for development of nursing intervention program for promoting quality of life in cancer patients. The design of this study was a cross sectional correlational survey. The subjects were 220 out and in-cancer patients in 5 general hospitals in Pusan The data were collected from July 2 to August 1,2001. The instruments were the Percieved social support scale(16 items, 5 point scale) had developed by Tae(1986), Hope scale(12 items, 4point scale) developed by Nowotny(1989) and Quality of life scale(31 items, 10 point scale) developed by Tae et. al(2000). The data was analyzed by the SPSS/PC+ program using frequency & percentage, item mean & standard deviation, t-test, ANOVA & Scheffe test, Pearson's correlation coefficient. The results of this study was as follows : 1) The item mean score of quality of life was 6.05±1.16 (range 0-10) .The heighest score of subarea of the quality of life was the spiritual wellbeing area (7.09±1.63) and the lowest score was social wellbeing area(5.53±1.65). The mean score of perceived social support was 52.65±10.32 (최고 1, 최저 80). The mean score of family support was32.71±6.66 (range 1- 40) and the mean score of medical team support was 19.93±5.95 (range 1- 40). The mean score of Hope was 37.02±5.64 (range 1-48). 2) There were statistically significant difference in the score of quality of life according to the life effect of religion (F=3.97, p=0.00), treatment method(F=2.94, p=0.01), area of diagnosis (F=3.48, p=0.01), stage of disease (F=13.74, p= 0.00). 3) There was significant correlation between perceived social support(r=0.44, p= 0.000 ; family support: r=0.334, p=0.000, medical support; r=0.395, p=0.000), hope(r=0.563, p= 0.000) and quality of life. In conclusion, there was a significant relationship among perceived social support, hope and quality of life. Therefore perceived social support, hope intervention programs should be developed to improve the quality of life in cancer patients.

부신피질 자극호르몬 단독결핍 1례

박경식,이승현,최석영,박태규,이동화,이찬우,정성복,이인규 啓明大學校 醫科大學 1997 계명의대학술지 Vol.16 No.3

부신피질 자극호르몬 단독결핍은 국내에서 7례만이 보고된 희귀 질환이며 병인 및 경과 등 아직 불분명한 측면이 많다. 이는 질환지체의 희귀성도 있지만 치료후 자연경과에 대한 장기적인 추적검사가 이루어진 경우가 드물기 때문이기도 하다. 저자들은 비특이적인 전신증상을 주소로 내원한 폐경기후의 56세 여자 환자에서 자가면역질환의 증거없이 고프로릭틴혈증을 보인 부신피질 자극호르몬 단독결핍 1례를 경험하고 1년간의 부신피질호르몬 대치요법후 추적검사를 실시하였기에 문헌 고찰과 함께 보고하는 바이다. Isolated ACTH deficiency is a rare disorder which shows secondary adrenal insufficiency with normal states of other pituitary hormones. A 56-year-old postmenopausal woman complaining general weakness and intermittent mental confusion presented negligible serum cortisol and ACTH level with hyperprolactinemia and mild hyponatremia. Rapid ACTH stimulation test did not show significant increase of serum cortisol level. Combined pituitary stimulation test showed negligible response of cortisol and ACTH, and slightly decreased response of prolactin and gonadotropin. But the responses of TSH and GH were normal. There was no evidence of organic pituitary of hypothalamic lesion in brain MRI and antithyroid autoantibody was not detected in serum. After receiving 12 months of glucocorticoid replacement therapy, she skipped the medicine for 3 weeks and we performed follow-up endocrinologic tests. Serum ACTH and cortisol level was also negligible and prolonged ACTH simulation test showed normal response of serum cortisol. CRF stimulation test showed no response of serum ACTH. Basal prolactin level was decreased to near normal and combined pituitary stimulation test showed normal response of prolactin with slightly blunted response of TSH and GH. We concluded that the case was nonautoimmune origined isolated ACTH deficiency which was accompanied by hyperprolactinemia and resultant deficiency of gonadotropin, so we report this case with review of literatures.

1995-96년 한반도 남동부 지역의 미소지진 자료를 이용한 지각구조 모델의 비교 연구

이기화,정태웅,Lee, Gi Hwa,Jeong, Tae Ung 한국지구물리물리탐사학회 1999 지구물리 Vol.2 No.1

한국자원연구소 지진관측망의 1995-96년 미소지진 자료를 바탕으로 한반도 남동지역의 지각구조에 대하여, Lee (1979), 김상조·김소구(1983), 김성균·정부흥(1985)의 세 지각 모델 중 어느 것이 잔차의 최소자승을 만족하는지 검증하였다. 세 모델 잔차의 뚜렷한 차이가 관찰되지 않았으나, Lee 의 지각 모델이 약간 깊은 진원을 산출하는 경향이 있다. 한반도 지각의 층상구조는 아직 명백하지 않으므로 앞으로 더 많은 자연지진 자료 또는 인공지진 자료를 통해서 규명되어져야 한다. Using the microearthquake data acquired from 1995 to 1996 through the seismic network operated by the Korea Institute of Geology, Mining & Materials (KIGAM), the three P-wave velocity models proposed by Lee (1979), Kim·Kim (1983) and Kim·Jung (1985) concerning the structure of the southeastern part of the Korean peninsula were examined in terms of the least square errors of the P-wave arrival times. The three models do not differ significantly in arrival time residuals except that the Lee's model gives slightly deeper focuses than the others. The layering of the crust of the peninsula is not clear as yet and to be studied by more earthquake and explosion data in the future.

일 간호대학의 간호환경시스템 통합실습방안 적용 : 간호관리학과 지역사회간호학의 통합

김광숙,이경자,김의숙,이정렬,김인숙,이태화,조윤희,정제인,이현정,배선형,김은현 대한간호학회 간호행정학회 2008 간호행정학회지 Vol.14 No.1

Purpose: Integrated curriculum has been considered as a desirable method in health related school course. The present study was conducted to develop practice curriculum which integrates nursing management and community health nursing and measure the education effect. Method: Literature review and scores of professional meeting were carried out to generate main educational goals, contents, operating principle, and evaluation item. Student evaluation was done by survey and in-dept interview in right after practicum and three months respectively. Results: Six concepts were derived as main component of the integrated curriculum. From 2 to 3 sub-categories were matched to each main component as well. Subsequently, practice contents were suggested on the basis of sub-categories. Attainment of practicum goal scores ranged from 2.82 to 3.54 in four points index. Students expressed that they found nursing manager's role in the community setting. Conclusion: This new approach encouraged students to ascertain relationship between hospital oriented and community based practice. Additionally, they can be prepared to comprehend diverse health care environment.

급성 심근경색 : Gd-DTPA 조영증강 자기공명영상 Gd-DTPA Enhanced Magnetic Resonance Imaging

정경일,김제현,이창호,이영주,김한수,소동문,이영돈,박경주,왕희정,탁승제,이철주,김선용,김옥화,임태환,문창현,최병일,서정호 아주대학교 의과학연구소 1996 아주의학 Vol.1 No.1

This study was undertaken to determine the value of gadolinium dimeglumine (Gd-DTPA) enhanced MRI in the diagnosis of acute myocardial infarction. Seven cats were subjected to 2 hours of left anterior descending coronary arteryocclusion (group 1) and 8 cats to 1 hour of occlusion (group 2). Reperfusion was followed by taking Tl-weighted MR images at 5, 15, 30, 45, 60 minutes after Gd-DTPA (0.2 mmol/kg) injection. Myocardial enhancement patterns were categorized into three zones (central ischemic, peripheral ischemic, and normal) or two zones (ischemic and normal) and the presence of injured myocardium in each zone was confirmed by 2,3,5-triphenyltetrazolium chloride (TTC) staining. Signal intensity (SI) of each zone was evaluated relative to back muscle in regard to its chronological changes and difference among the zones. Group 1 displayed three zones of enhancement in 6 cats whereas 1 cat in group 1 and all in group 2 showed two zones of enhancement. Intermediate SI central zone was compatible but smaller than TTC nonstained area, and determined to be a persistently occlusive injury. High SI peripheral zone in group 1 and high SI ischemic zone in group 2 were stained and determined as reperfused injury although reversibility was not definite. The peak SI, occurring 15 minutes after Gd-DTPA injection, of 2.47±0.48 at peripheral zone was greater than that of 1.66±0.36 at central zone in group 1 and of 1.81±0.41 at ischemic zone in group 2 (p < 0.05). SI of injured myocardium increased more rapidly and decreased more gradually than that of normal myocardium. That the features of SI change with time in injured myocardium was compatible with the results of other studies using different contrast agents. Gd-DTPA enhanced MRI differentiated persistently occlusive injury as central intermediate SI, and reperfused injury as homogenous high SI, with the maximal contrast between the two at 15 minutes after contrast injection, thus indicating the value of Gd-DTPA enhanced MRI in the diagnosis of acute myocardial infarction.

뇌척수액내의 결핵균 α- 및 β- 단백항원에 반응하는 항결핵균항체의 정량적 측정에 의한 결핵성 수막염의 진단적 접근

이경숙,백태현,김화중,박정규,최대경 충남대학교부설 생명공학연구소 1992 생물공학연구지 Vol.2 No.-

The aim of this study was to develop an immunologic method for the diagnosis of tuberculous meningitis with a sensitivity greater than that of the initial bacterial smear while maintaining good specificity. Purified α-antigen and β-antigen from unheated culture filtrate of Mycobacterium tuberculosis H37Rv was applied for its potential diagnostic utility in detection of IgG, IgM and IgA antibody in the cerebrospinal fluids of 14 patients with tuberculous meningitis and 27 non-tuberculous patients by ELISA at the CSF dilution of 1 : 5. The results were summarized as follows: 1. The mean ELISA values of IgG antibody activity to purified α-antigen in CSF of 14 patients with tuberculous meningitis and 27 controls were 0.769±0.638 and 0.090±0.068, respectively. The specificity and sensitivity were 96.3% and 92.9%. The mean ELISA values of IgG antibody activity to purified β-antigen were 0.668±0.507 and 0.092±0.070, respectively. The specificity and sensitivity were 92.6% and 92.9%. 2. The mean ELISA values of IgM antibody activity to purified α-antigen in CSF of 14 patients with tuberculous meningitis and 27 controls were 0.629±0.585 and 0.007±0.076, respectively. The specificity and sensitivity were 92.6% and 92.9%. The mean ELISA values of IgM antibody activity to purified β-antigen were 0.637±0.550 and -0.028±0.082. The specificity and sensitivity were 96.3% and 85.7%. 3. The mean ELISA values of IgA antibody activity to purified α-antigen in CSF of 14 patients with tuberculous meningitis and 27 controls were 0.266±0.330 and -0.22±0.032. The specificity and sensitivity were 96.3% and 85.7%. The mean ELISA values of IgA antibody activity to purified β-antigen were 0.031±0.419 and -0.048±0.037. The specificity and sensitivity were 96.3% and 85.7%. These results suggest that the purified α-and β-antigen are useful for the diagnosis of tuberculous meningitis.

메조기공의 실리카-티타니아 코겔의 제조와 자율적 조습 및 광촉매 특성

이상화,곽중협,서태수,김효중,김동표 한국공업화학회 2003 공업화학 Vol.14 No.3

수용액상의 졸겔반응에 의해 메조기공의 실리카-티타니아 코겔을 제조하고 이들의 자율적 조습력과 광촉매 특성에 대해 검토하였다. 실리카-티타니아 코겔에 있어 조습력과 관계되는 세공크기와 용적은 본 연구에서 고안된역적정법에 의해 Ph 7부근 및 SiO_2/TiO_2 비가 상대적으로 큰 9/1인 경우에 가장 큰 생성물이 얻어졌다. 폐놀 분해율에 의한 광촉매 특성은 동일조건에서 SiO_2/TiO_2 비가 감소함에 따라 증가하였고, SiO_2/TiO_2 비가 9/1에서 세공크기 4.0~6.0 nm 및 세공용적 0.6~0.8 mL/g 범위로 제어된 코겔의 경우 환경습도 40~70% 범위에서 흡습량 25%, 방습량 45%로서 종래 조습재료 보다 자율조습력이 큰 것을 볼 수 있었고, 같은 조성의 실리카-티타니아 혼합 산화물과의 폐놀 분해율에 의한 광촉매 특성 비교에서도 우수한 물성을 보이고 있었는데 이것은 Ti-O-Si 결합형성으로 인해 코겔 구조내에 음전하 과잉으로 인한 활성점(브렌스테드 산점) 발현에 기인된 것으로 고찰된다. Silica-titania cogel materials have been prepared by aqueous sol-gel process using a back titration technique designed for this study. The humidity self-control and photocatalytic properties of the materials have been also investigated. In these silica-titania cogel materials, relatively large pore size and pore volume than can give a good humidity control ability are desired, and they were synthesized under the reaction condition at pH of 7 and SiO_2/TiO_2 ratio of 9/1. The photocatalytic property, which was measured by the decomposition ratio of phenol, increased with the decrease of SiO_2/TiO_2 ratio in the composition. The cogel at the SiO_2/TiO_2 ratio of 9/1, resulted in the pore size of 4.0~6.0 nm and the pore volume of 0.6~0.8mL/g. At the relative humidity range of 40~70%, the amounts of moisture absorption and desorption were 25% 45%, respectively, and these had a better humidity control ability than conventional ones. In addition, the cogel showed a superior photocatalytic property compared to that of silica and titania mixture with the same composition. This enhancement is probably due to the revelation of active sites by the excess negative charges that were induced by Ti-O-Si bond formation in the cogel structure.

중증 임신성 혈소판감소증 분만 1예

이태화,이천준 고신대학교의과대학 2007 고신대학교 의과대학 학술지 Vol.22 No.2

Gestational thrombocytopenia can be defined either as a specific disorder or as a group of thrombocytopenic disorders that occur in pregnancy. Some physicinas have defined gestational thrombocytopenia as the benign thrombocytopenic disorder that occurs in pregnancy at a relatively high frequency. But severe Gestational thrombocytopenia(platelets<5,000/mm3) is rare. The pathogenesis of thrombocytopenia in the gestation is not fully understood. The primary goal in managing a gestational thrombocytopenia is to deliver a healthy infant without unwarranted risk to the mother's health. We experienced a case of delivery in severe gestational thrombocytopenia so we report this case with a brief review of literature.

자궁외 위치한 자궁내장치 1예

이태화,김성한 고신대학교의과대학 2008 고신대학교 의과대학 학술지 Vol.23 No.4

Intrauterine devices(IUDs) remain one of the main methods of choice for birth control over the world, especially in developing countries. Uterine perforation is a rarely observed complication. A misplaced intrauterine device can migrate to various positions in the pelvic or intra-abdominal cavity, which may cause a range of complications and morbidities. The currently accepted treatment of choice for IUDs is its removal by surgical laparoscopy or laparotomy. We report one case with misplaced IUD in the omentum, followed by a review of literature.