In_xGa_1-xN/GaN 다중양자우물 구조의 광학적 성질 연구

김기홍,김인수,박헌보,배인호,유재인,장윤석,Kim, Ki-Hong,Kim, In-Su,Park, Hun-Bo,Bae, In-Ho,Yu, jae-In,Jang, Yoon-Seok 한국진공학회 2009 Applied Science and Convergence Technology Vol.18 No.1

$In_xGa_{1-x}N$/GaN 다중양자우물 구조의 EL 특성을 온도와 주입전류 변화에 따른 특성을 조사하였다 저전류와 고전류 주입시 EL 효율의 온도 의존 변화는 매우 다르게 나타나는데, 이러한 온도와 전류의 변화에 의한 독특한 EL 효율의 변화는 내부전기장의 존재 하에 순방향 바이어스에 기인한 외부전기장의 영향인 것으로 볼 수 있다. 그리고 $In_xGa_{1-x}N$/GaN 다중양자우물 구조에서 In 성비의 증가는 발광파장위치의 적색이동을 보였다. 15K에서 주입 전류의 증가에 따라 녹색 양자우물 구조는 80 meV와 청색 양자우물 구조는 22 meV의 청색 편이를 하였다. 이는 전류의 증가에 의해 단위 시간당 생성되는 캐리어 수가증가하게 되고 그에 따라 subband가 급격히 채워지는 band filling 현상이 일어나게 되어 짧은 파장에서 재결합이 증가하기 때문이다. 그리고 청색과 녹색 다중 양자우물구조의 짧은 파장 쪽으로의 편이 차이는 In 농도에 기인한 것으로 In 농도가 높으면 양자우물 깊이가 증가되어 더 강한 양자속박효과가 작용하여 캐리어 구속력이 증가하기 때문 것으로 볼 수 있다. Temperature and injection current dependence of electroluminescence(EL) spectral intensity of the $In_xGa_{1-x}N$/GaN multi-quantum wells(MQW) have been studied over a wide temperature range and as a function of injection current level. It is found that a temperature-dependent variation pattern of the EL efficiency under very low and high injection currents shows a drastic difference. This unique EL efficiency variation pattern with temperature and current can be explained field effects due to the driving forward bias in presence of internal(piezo and spontaneous polarization) fields. Increase of the indium content in $In_xGa_{1-x}N$/GaN multiple quantum wells gives rise to a redshift of 80 meV and 22 meV for green and blue MQW, respectively. It can be explained by carrier localization by potential fluctuation of multiple quantum well and MQW structures also shows a keen difference owing to the different indium content in InGaN/GaN MQW.

공군사관생도의 심폐능력에 따른 심리 · 생리요인 비교

김인기(In-ki Kim),김건희(Gun-hee Kim),송성우(Sung-woo Song),최가람(Ga-ram Choi),엄장원(Jang-won Eom),곽재준(Jae-jun Kwak),유영남(Young-nam You),정덕화(Deok-hwa Jeong),강지훈(Ji-hun Kang) 육군사관학교 화랑대연구소 2019 한국군사학논집 Vol.75 No.2

The purpose of this study was to analyze the differences in psychological and physiological factors between groups by classifying groups based on the 3km running record of fourth grade Air Force Academy cadets. Among the top 46 Air Force Academy cadets who wanted to participate in the study, the study conducted an open survey of the top 13 and the bottom 15 who wanted to provide the data prior to the study. The subjects of the experiment and in-depth interview were studied by a total of 18 people, 9 of each upper and lower members who wished to participate in the study. Psychological factors were structured through inductive content analysis of data extracted from in-depth interviews, and physiological factors were conducted to verify differences between groups of body composition and cardiopulmonary function. The psychological factors of the upper and lower groups were found to be general areas of performance strategy, achievement motivation, emotional response, military spirit, situation perception, and basic physical strength. In the detailed areas, the subjects were also examined in 15 areas including physical fitness indicators, confidence, condition control, task orientation, and positive self-perception. As a result of comparison between upper and lower groups, the upper group was 2.2 times higher than the lower group and the lower group was 1.7 times higher than the upper group in the military spirit and performance strategy of the general area response rate. In general area response, the ratio of mental strength and confidence was different in the general area of military spirit. In addition, the upper group in the achievement motivation showed a high percentage of task tendency at 47%, while the lower group showed a high rate of zero motivation at 50%. In the emotional response, the upper group showed an equal ratio, while the lower group showed an 81% ratio of negative emotions. In the overall response by sub-region, the negative emotions of the subgroup were high at 28%. In the body composition, BFM showed a statistically significant difference between upper and lower groups, and Weight, FFM, and SMM did not show any significant difference between groups. In cardiopulmonary capacity, VO2max showed a statistically significant difference between upper and lower groups, and VE and LT did not show significant differences between groups.

관동맥질환에서 저밀도 지단백 입자 크기의 분포

임효영,김인숙,승기배,강동헌,전두수,장기육,박준철,이수영,홍순조,최규보 대한순환기학회 1998 Korean Circulation Journal Vol.28 No.8

원발성 유방암에서 Sodium Iodide Symporter의 발현과 ^(99m)Tc-MIBI 유방스캔의 관계

석주원,김성장,곽희숙,이창훈,김인주,김용기,배영태,김동수 대한핵의학회 2002 핵의학 분자영상 Vol.36 No.6

목적: hNIS는 갑상선 조직 외에 다른 조직들에서도 발현된다고 알려져 있다. 유방암 세포는 그런 조직들 중에 하나이며, 그에 의한 유방암의 방사성옥소치료의 가능성이 제시되고 있다. 본 연구에서는 유방암 조직에서 hNIS의 발현정도를 알아보고, ^99mTc-MIBI 유방스캔과 hNIS의 발현 정도와의 관계를 조사하여 보았다. 대상 및 방법: 본 연구에서는 유방암으로 수술을 시행했던 56명의 환자를 대상으로 하였다. hNIS의 발현은 면역조직화학염색에 의해서 평가되었으며, 그 결과를 ^99mTc-MIBI 유방스캔의 판정 결과와 비교하였다. 결과: 전체 56명의 환자에서 hNIS의 발현율은 41.1%였다. 병리학적 진단에 의해 침윤성관상피암종이었던 49명에서의 발현율은 42.9%, 관상피내암종이었던 7명에서의 발현율은 28.6%였다. ^99mTc-MIBI 유방스캔에서 국소섭취 소견이 관찰되었던 41명에서의 hNIS의 발현율은 31.7%였다. 비정상적인 섭취 소견이 관찰되지 않았던 15명의 환자에서의 hNIS의 발현율이 의미있게 높게 관찰되었다(66.7%, p>0.05). 결론: 유방암 환자에서의 hNIS의 발현율은 그다지 높지 않았다. ^99mTc-MIBI 유방스캔에서 섭취증가 소견이 없을 때 hNIS의 발현율이 더 높았다. Purpose: Human Na^+/I- symporter (hNIS) is known to be expressed in many tissues other than thyroid gland. The breast cancer cells are one of them and the possibility of radioiodine therapy in treatment of the breast cancer may be suggested. We investigated the expression rate of hNIS and the relationship between the expression of hNIS and the finding of 99mTc-MIBI scintimammography in the breast cancer. Materials and Methods: Surgically proved 56 patients with breast cancer were the subjects of this study. The expression of hNIS were evaluated by immunohistochemistry and the results were compared to the findings of 99mTc-MIBI scintimammography. Results: Overall expression rate of hNIS was 41.1% in 56 patients. According to the pathologic diagnosis, it was 42.9% in 49 patients with invasive ductal carcinoma and 28.6% in the 7 patients with ductal carcinoma in situ. The expression rate of hNIS in the 41 cases with a focal increased uptake at he breast lesion on 99mTc-MIBI scintimammogram was 31.7%. That in the 15 cases without any abnormal uptake on the scan was significantly higher(66.7%, p<0.05). Conclusion: The expression rate of hNIS in the patients with breast cancer was not so high. The rate was higher in the patients with no increased uptake at the breast lesion on 99mTc-MIBI scintimammography. (Korean J Nucl Med 2002;36;325-32)

생쥐 위장관의 Interstitial cells of Cajal(ICC)에 대한 면역조직화학적 연구

김영철,차경훈,신무경,임건한,김주영,안병수,김장만,양경철,박도영,오재욱,장인엽 조선대학교 2003 The Medical Journal of Chosun University Vol.28 No.1

Background and Objectives : Interstitial cells of Cajal(ICC) are the pacemakers in gastrointestinal tract that modulates gastrointestinal motiliey and these cells also transmit neural input from enteric nerves to smooth muscles. Recent work on tissues from patients with motility disorders that suggest that loss or defect in ICC could be related to pathophysiology in human and animal models. Immunolabelling of ICC in intestinal wall is recently developed by using specific marker, anti-c-kit antibody. Immunohistochemistry was done for ICC network in attempt to provide a morphological basis for the mechanism regulating gastrointestinal motility Methods : Cryosection was done, and whole-mount preparations of mouse stomach, gastrointestinal tract were immunolabelled using the anti-c-Kit. Immunolabelled ICC networks were observed under a confocal laser scanning microscopy. Results : According to three dimensional reconstruction study, we found that the c-Kit-positive celluar networks were widely distributed in the gastrointestinal muscle (1) circular muscle layer(IC-IM), (2) myenteric plexus(IC-MY), (3) deep muscular plexus(IC-DMP) in ileum, (4) submucosal plexus(IC-SMP) and longitudinal muscle layer(IC-LM) in colon. Conclusion : The characteristic profiles of ICC celluar networks provide a morphological basis upon the mechanism regulating gastrointestinal motility. Additional studies for the enteric nerves-ICC interaction are need to evaluate the detailed roles of Icc in gastrointestinal tract.

급성 심근경색증 환자에서 일차적 관상동맥 중재술 후 장기적 임상 경과-65세를 기준으로

이한올(Han-Ol Lee),장성주(Seong-Joo Jang),김인수(In-Soo Kim),한재복(Jae-Bok Han),박수환(Soo-Hwan Park),김정훈(Jeong-Hun Kim),장영일(Young-Ill Jang) 한국콘텐츠학회 2014 한국콘텐츠학회논문지 Vol.14 No.5

본 연구는 일차적인 경피적 관상동맥 중재술(percutaneous coronary intervention, PCI)를 시술 받은 65세 이상의 고령 환자들에서 임상적 특성, 관상동맥 병변 및 중재술의 특성, 병원 내 및 1년 사망률과 주요심장사건(major adverse cardiac events, MACE)의 발생에 대해 알아보고자 하였다. 2006년 1월 1일부터 2010년 12월 30일까지 모 대학병원 심혈관센터에서 급성 심근경색증으로 진단받고 흉통 발생 12시간 이내 관상동맥 조영술 및 일차적 PCI를 시행 받은 환자 1,974예를 대상으로 하였고, 65세 이상의 I군(1,018예, 연령 73.8±5.99세, 남자 : 여자 =574 : 821)과 65세 이하의 II군(956예, 연령 52.8±7.96세, 남자 : 여자 = 444 : 135)으로 나누어 분석하였다. 심혈관질환의 위험인자는 I군에서 더 높았고, 흡연력, 고지혈증, 가족력은 II군에서 높았다. PCI표적 병변은 I군에서 좌주관지(2.7 vs. 1.6%, p=0.007)가 유의하게 많았으며, 다혈관병변(54.5 vs. 41.0%, p<0.001)도 I군에서 많았다. 병원 내 사망(8.4 vs. 1.9%)과 MACE(20.1 vs. 14.0%)는 I군에서 많이 관찰되었다(p<0.001). 로지스틱 다중회귀분석 결과 65세 이상 고령 환자에서 1년 사망률에 영향을 미치는 독립적인 인자는 내원 시 혈중 creatinine 1.3 mg/dL 이상, 뇌혈관 질환, 수축기 혈압<100 mmHg, Killip class II이상, 다혈관 질환, 그리고 좌심실 구혈률<40%로 나타났다. Primary percutaneous coronary intervention (PCI) has been found to be superior, in terms of hospital mortality and long-term outcome, compared with thrombolytic therapy in patients with acute myocardial infarction (AMI). However, the clinical benefits of primary PCI have not been precisely evaluated in elderly patients.1,974 patients (Group I: n=1,018, age≥65years, 73.8±5.99years; Group II: n=956, age<65years, 52.8±7.96years) who underwent primary PCI for AMI at Chonnam National University Hospital between 2006 and 2010 were analyzed according to their clinical, angiographic characteristics for hospital and one-year survival. Group I had a higher percentage of women, diabetes mellitus, hypertension, multi-vessel disease and lower prevalence of current smoking, hyperlipidemia, familial history than Group II. Culprit lesions were at the left anterior descending artery, left circumflex artery, right coronary artery and left main artery in 42.8% vs. 45.0%, 34.1% vs. 29.6%, 14.6% vs 14.6, 2.7% vs. 1.6%, respectively (p=0.007). Stent diameter was smaller in group I (3.17±0.39 vs. 3.29±0.42mm, p=0.001). In-hospital mortality was higher in group I (8.4 vs. 1.9%, p<0.001). There were significant differences in the rates of major adverse cardiac events between the two groups during one-year clinical follow-up (20.1 vs.14.0%, p<0.001). On multiple logistic regression analysis, systolic blood pressure<100mmHg, serum creatinine≥1.3mg/dL, Killip class> I, multivessel disease, left ventricular ejection fraction<40% and cerebro vascular disease were independent predictors of one-year motality in patients over 65 years after PCI.

Portable multi-parameter electrical impedance tomography for sleep apnea and hypoventilation monitoring: feasibility study

Lee, Min Hyoung,Jang, Geuk Young,Kim, Young Eun,Yoo, Pil Joong,Wi, Hun,Oh, Tong In,Woo, Eung Je IOP 2018 Physiological measurement Vol.39 No.12

<P> <I>Objective</I>: Quantitative ventilation monitoring and respiratory event detection are needed for the diagnosis of sleep apnea and hypoventilation. We developed a portable device with a chest belt, nasal cannula and finger sensor to continuously acquire multi-channel signals including tidal volume, nasal pressure, respiratory effort, body position, snoring sound, ECG and SpO<SUB>2</SUB>. The unique feature of the device is the continuous tidal volume signal obtained from real-time lung ventilation images produced by the electrical impedance tomography (EIT) technique. <I>Approach</I>: The chest belt includes 16 electrodes for real-time time-difference EIT imaging and ECG data acquisitions. It also includes a microphone, accelerometer, gyroscope, magnetometer and pressure sensor to acquire, respectively, snoring sound, respiratory effort, body position and nasal pressure signals. A separate finger sensor is used to measure SpO<SUB>2</SUB>. The minute ventilation signal is derived from the tidal volume signal and respiration rate. <I>Main results</I>: The experimental results from a conductivity phantom, four swine subjects and one human volunteer show that the developed multi-parameter EIT device could supplement existing polysomnography (PSG) and home sleep test (HST) devices to improve the accuracy of sleep apnea diagnosis. The portable device could be also used as a new tool for continuous hypoventilation monitoring of non-intubated patients with respiratory depression. <I>Significance</I>: Following the feasibility study in this paper, future validation studies in comparison with in-lab PSG, HST and end-tidal CO<SUB>2</SUB> devices are suggested to find its clinical efficacy as a sleep apnea diagnosis and hypoventilation monitoring tool.</P>

Screening with the Korean Version of the Mood Disorder Questionnaire for Bipolar Disorders in Adolescents: Korean Validity and Reliability Study

Se-Hoon Shim,Jong-Hun Lee,Jye-Heon Song,Beomwoo Nam,Bo-Hyun Yoon,Ha-young Jin,Hyung-Mo Sung,Jong Hyun Jeong,Sae-Heon Jang,Duk-In Jon,Young Sup Woo,Won-Myong Bahk 대한정신약물학회 2018 CLINICAL PSYCHOPHARMACOLOGY AND NEUROSCIENCE Vol.16 No.3

Objective: This study aimed to evaluate the validity and reliability of a Korean version of the Mood Disorder Questionnaire-Adolescent version (K-MDQ-A) as a screening instrument for bipolar disorders in adolescents. Methods: One hundred two adolescents with bipolar disorders and their parents were recruited from November 2014 to November 2016 at 7 training hospitals. One hundred six controls were recruited from each middle school in two cities of South Korea. The parent version of the original MDQ-A was translated into Korean. The parents of all participants completed the K-MDQ-A. The diagnoses of bipolar disorders were determined based on the Korean version of K-SADS-PL. The test-retest reliability with a 10-month interval was investigated in 33 bipolar adolescents. Results: K-MDQ-A yielded a sensitivity of 0.90 and a specificity of 0.92 when using a cut-off score of endorsement of 5 items, indicating that symptoms occurred in the same time period and caused moderate or serious problems. The internal consistency of the K-MDQ-A was good. The correlations between each item and the total score ranged from 0.40 to 0.76 and were all statistically significant. Factor analysis revealed 3 factors that explained 61.25% of the total variance. The mean total score was significantly higher in bipolar adolescents (7.29) than in controls (1.32). The Pearson correlation coefficient for the total test-retest score was 0.59 (p<0.001). Conclusion: The K-MDQ-A completed by parents showed the excellent validity and reliability and may be a useful screening tool for adolescents with bipolar disorders attending in- and outpatient psychiatric clinics.

사용자환경정보 기반 Context-based Service 추론모델

고광은(Kwang-Eun Ko),장인훈(In-Hun Jang),심귀보(Kwee-Bo Sim) 한국지능시스템학회 2007 한국지능시스템학회논문지 Vol.17 No.7

현재의 유비쿼터스 컴퓨팅 기술은 공간에서 사용자가 요구하는 직접적인 서비스만을 제공하는 정도의 기술 구현에 그치고 있으며, 앞으로는 좀 더 능동적인 서비스를 제공할 수 있는 지능적인 시스템이 필요해지고 있다. 사용자의 개입 없이 사용자가 처한 상황에 대한 정보를 통해 제공할 서비스를 결정할 수 있는 시스템을 구성하기 위해 본 논문에서는 지능형 홈과 같은 유비쿼터스 컴퓨팅 공간에서의 사용자가 처한 상황에 대한 환경정보를 Context로 정의하고 4W1H의 형태로 정형화하여 수집한다. 추가적으로 사용자의 감정 상태에 대한 정보를 수집하고 이러한 정보들을 확률 추론을 위한 베이지안 네트워크의 노드로 사용하여 사용자가 구체적으로 어떠한 상황에 처해 있는가에 대한 상황인식을 구현하다. 또한 그 상황 인식결과를 통해 사용자에게 제공될 서비스를 다시 한 번 베이지안 네트워크를 통해 추론하는 모델을 제시하고자 한다. The present level of ubiquitous computing technology have developed to the point where Home-server provides services that user require directly for user in the intelligent space. But it will need intelligent system to provides more active services for user in the near future. In this paper, we define the environment information about situation that user is in as Context, and collect the Context that stereotype as 4W1H form for construct the system that can decision service will be provide from information about a situation that user is in, without user's involvement. Additionally we collect information about user's emotional state, use these informations as nodes of Bayesian network for probabilistic reasoning. From that, we materialize Context Awareness system about it that what kind of situation user is in. And, we propose the Context-based Service reasoning model using Bayesian Network from the result of Context Awareness.

VDT작업별 정신사회적 스트레스와 근골격계 장애에 관한 연구

백남종,강종두,주영수,배인근,권호장,박종만,조수헌,김돈규,김재용,최홍렬 大韓産業醫學會 1998 대한직업환경의학회지 Vol.10 No.4

It has been hypothesized that jobs that have both high psychological demands and low decision latitude("job strain") can lead to musculoskeletal disorder. The objective of this study was to test whether job strain was correlated with the presence of work-related musculoskeletal disorder, especially myofascial pain syndrome(MPS). Information on demographic factors, confounders such as household load and taking care of children or not, and scores for decision latitude, job demand, and social support was obtained by self-administered questionnaire, which had been developed in Korean language, by adopting NIOSH instrument and Extended Karasek Model(16 items). All subjects were also examined by rehabilitation medicine specialists for musculoskeletal disorders. Subjects(n=370) could be categorized into 4 groups, these were, housewives(n=89), shipyard CAD workers(n=89), general female workers(n=79; nurses, insurance counselors, public officials, clerks, etc), and telephone directory assistance operators(n=113). Results from univariate analyses indicated that all demographic factors, all confounders, scores for decision latitude and social support were not associated with the risk of musculoskeletal disorder. However, score for job demand was higher in musculoskeletal disorder cases than others. In subgroup analysis, this association was convinced again, in telephone directory assistance operators. Job strain model showed that the group of telephone directory assistance operators was high-stain group, and OR of musculo skeletal disorder was 2.446(95% C. I. : 1.174, 5.096), when comparing this with the low strain group. In conclusion, job strain is a risk factor for work-related musculoskeletal disorder.