관동맥연축의 진단을 위한 Ergonovine Echocardiography의 안전성 및 임상적 유용성

송재관,박성욱,강덕현,조구영,나득영,이내희,이철환,홍명기,김재중,박승정 대한순환기학회 2000 Korean Circulation Journal Vol.30 No.8

비심인성 흉통환자에서 흉통의 원인으로서의 식도질환

송재관,민영일,김해련,양석균,이근찬 대한소화기학회 1994 대한소화기학회지 Vol.26 No.1

Noncardiac chest pain is a vexing diagnostic problem. Recently, awareness of the potential for the esophagus to cause chest pain is increasing, But a causal relationship between esophageal motility or reflux disease and chest pain may be difficult to prove. We perform this study to evaluate the importance of esophageal abnormalities as a potential cause of recurrent noncardiac chest pain. We underwent endoscopy, esophageal manometry with edrophonium provocation test and 24hour esophageal pH monitoring in 54 patients with normal coronary arteriogram and negative vascular spasm study. Eighteen patients (33%) had abnormal esophgeal manometry test and in 15 patients, the chest pain could be provocated with edrophonium injection (80,ug/kg). But only 6 patients (11 %) showed positive edrophonium provocation test and abnormal motilty test. These were 3 cases of diffuse esophgeal spasm, I case of nutcracker esophagus and 2 cases of hypertensive lower esophageal sphincter(LES). In twenty eight patients with 24hour pH monitoring, 9 patients (32.1%) had pathologic reflux and 1 9 patients experienced chest pain during test time. Ten patients out of 1 9 patients had positive symptom index (S.I,) and 6 patients (31.6%) had both pathologic reflux and pisitive S.I.. Mean S.I. of these 6 patients was 65.5% (range 50-100%). In conclusion, about 40% of patients with noncardiac chest pain had esophageal disease as probable cause of chest pain and gastroescphaical, reflux disease as well as esophageal motility disease was important cause of chest pain even if without evidence of reflux esophagitis.(Korena J Gastroenterol 1994 : 26 : 1-8)

자동기계에 의한 우편물 순로구분 동향

송재관,황재각,박문성,남윤석,김혜규,Song, J.G.,Hwang, J.G.,Park, M.S.,Nam, Y.S.,Kim, H.K. 한국전자통신연구원 2000 전자통신동향분석 Vol.15 No.6

자동구분기계에 의한 우편물 처리 절차는 수집된 우편물을 우편집중국으로 보내고 OVIS를 이용하여 우편물에 기재된 우편번호를 인식하여 바코드로 변환한 다음 우편물에 바코드를 인쇄한다. 이 우편물은 LSM에 의해 바코드를 자동 판독하여 분류한 다음 각 지역별로 운송하게 된다. 운송된 우편물은 배달우체국으로 보내지게 되고 배달원이 자신의 배달구역의 우편물을 가지고 각 가정이나 사무실 등에 우편물을 배달하게 된다. 이 우편물을 배달순서대로 정렬하는 과정을 순로구분이라고 하는데, 우편물의 자동처리에 있어 가장 많은 시간이 소요되는 부분은 바로 이 순로구분 과정이다. 현재는 이 과정을 배달원이 자신의 경험에 의해 수작업으로 처리하고 있는 실정이며 우편물을 신속하고 정확하게 처리하고 원가를 절감하기 위해서는 기계에 의한 순로구분자동화가 이뤄져야 한다. 특히, 우편물의 익일배달체계를 실현하기 위해서는 순로구분이 자동으로 이뤄져야 한다. 이에, 본 고는 우리나라의 순로구분자동화 방안을 모색하기 위해 우정선진국의 순로구분자동화 동향을 분석하였다.

放射線이 人體에 미치는 影響과 效果

宋在寬 대구보건대학 1987 대구보건대학 論文集 Vol.10 No.-

It is known beyond a shadow of a doubt that ⅹ-rays are harmful. If sufficiently intense they can cause cancer, leukemia, and genetic damage. What is not known for certain is the degree of effect following diagnostic levels of ⅹ-radiation. We do know that the benefits derived from the diagnostic application of ⅹ-rays in medicine are enormous. It is the job of the technologist, along with the radiologist, physicist, and maintenance engineer, to produce high-quality ⅹ-ray studies with a minimum of radiation exposure. This approach can result in the highest benefit and the smallest risk. The effects of ⅹ-rays on humans are the result of interactions at atomic levels. These atomic interactions take the form of ionization or excitation of orbital electrons and result in the deposition of energy in tissue. The deposited energy can result in a molecular change, the consequences of which can be disastrous if the molecule involved is critical. Fig.⑴ summarizes the steps between radiation exposure and latent wholebody injury When an atom is ionized, its chemical binding properties change. If the atom is a constituent of a large molecule, the ionization may result in breakage of the molecule or relocation of the atom within the molecule. The abnormal molecule may in time function improperly or cease to function, which can result in serious impairment or death of the cell. This process is not irreversible. At each stage in the sequence it is possible to recover from radiation damage. Ionized atoms can become neutral again by attracting a free electron. Molecules can be mended by repair enzymes. Cells and tissues can regenerate and recover from the radiation injury. If the radiation injury occurs within minutes or days after radiation exposure, it is classified as an immediate or early of radiation. On the other hand, if the human injury is not observable for many months or years, it is termed a delayed or late effect of radiation. The following outline summarizes the possible early and late human responses to radiation exposure. In addition many other radiation responses have been experimentally observed in animals. Most of the human responses have been observed following rather large radiation doses. But we are cautious and assume that even small doses are harmful.

변이형협심증 환자의 진단에 있어 Bedside Intravenous Ergonovine Test의 임상적 유용성에 관한 연구

송재관,박성욱,두영철,김재중,박승정,이종구 대한순환기학회 1992 Korean Circulation Journal Vol.22 No.1

How Does the Left Ventricle Work? Ventricular Rotation as a New Index of Cardiac Performance

송재관 대한심장학회 2009 Korean Circulation Journal Vol.39 No.9

Although simple cylindrical or ellipsoidal left ventricular (LV) geometry with transverse or circumferential muscle contraction has been traditionally used to estimate LV performance, the estimated LV ejection fraction (EF) with muscle fiber shortening up to 20% is less than 50% of maximum, which is lower than the normal EF observed in routine clinical practice. Thus, oblique fiber orientation and LV rotation, in addition to radial thickening and longitudinal shortening, is predicted as an essential component of effective LV pumping. This was confirmed by animal experiments using surgically implanted markers or invasive sonomicrometry. Demonstration of the muscle band extending from the pulmonary artery to the aorta, which connects the ventricular myocardium, both right ventricle and LV as a continuous band (muscle band theory) provides an anatomical backbone of helical configuration of the cardiac muscle band with descending and ascending segments wrapping the LV apex. Moreover, sequential, non-simultaneous, activation and contraction of the helicoids muscle band contributes to LV rotation or twist motion. Recently, magnetic resonance imaging and speckle tracking echocardiography (STE) techniques have provided an excellent noninvasive way to measure LV rotation and twist, which is expected to contribute to a more thorough evaluation of both LV systolic and diastolic function. Initial animal experiments showed that quantification of apical rotation or LV twist using STE is more accurate for estimating LV systolic function than conventional EF under a variety of LV inotropic conditions, irrespective of coronary ligation. As de-rotation or the untwisting rate can also be measured by STE, the role of ventricular untwisting as a temporal link between LV relaxation and suction can be addressed. Further clinical investigations are needed to determine the real clinical impact of these new indices of LV mechanical function. Although simple cylindrical or ellipsoidal left ventricular (LV) geometry with transverse or circumferential muscle contraction has been traditionally used to estimate LV performance, the estimated LV ejection fraction (EF) with muscle fiber shortening up to 20% is less than 50% of maximum, which is lower than the normal EF observed in routine clinical practice. Thus, oblique fiber orientation and LV rotation, in addition to radial thickening and longitudinal shortening, is predicted as an essential component of effective LV pumping. This was confirmed by animal experiments using surgically implanted markers or invasive sonomicrometry. Demonstration of the muscle band extending from the pulmonary artery to the aorta, which connects the ventricular myocardium, both right ventricle and LV as a continuous band (muscle band theory) provides an anatomical backbone of helical configuration of the cardiac muscle band with descending and ascending segments wrapping the LV apex. Moreover, sequential, non-simultaneous, activation and contraction of the helicoids muscle band contributes to LV rotation or twist motion. Recently, magnetic resonance imaging and speckle tracking echocardiography (STE) techniques have provided an excellent noninvasive way to measure LV rotation and twist, which is expected to contribute to a more thorough evaluation of both LV systolic and diastolic function. Initial animal experiments showed that quantification of apical rotation or LV twist using STE is more accurate for estimating LV systolic function than conventional EF under a variety of LV inotropic conditions, irrespective of coronary ligation. As de-rotation or the untwisting rate can also be measured by STE, the role of ventricular untwisting as a temporal link between LV relaxation and suction can be addressed. Further clinical investigations are needed to determine the real clinical impact of these new indices of LV mechanical function.

페로브스카이트 태양전지 안정성 개선을 위한 광활성층 연구 현황과 전망

송재관,김도형 한국화학공학회 2020 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.58 No.1

Development of efficient methods for clean energy production became a critical issue to improve the quality of human lives. Solar cells is considered as one of the alternative solutions to resolve the issue. Although Si-based solar cells are only popularly utilized for practical applications, high manufacturing cost is considered as a serious drawback for further versatile applications. Thus, different types of are being investigated aiming to replace the Si-based solar cells. Recently, perovskite solar cells (PSC) are considered as a potential replacement for Si-based solar cells due to their low production cost, high power conversion efficiency, light weight and possibility of flexible device fabrication. Thus, we have reviewed the challenges of PSC faced with practical application, particularly on stability. 화석 연료를 이용하는 에너지원이 심각한 환경오염을 일으키고, 인류의 건강한 삶에 큰 영향을 주어 청정한 에너지자원의 개발은 매우 중요한 이슈가 되었다. 화석 연료를 대체하기 위한 다양한 에너지원의 개발이 진행되고 있으며, 그중 최근에는 태양 전지에 대한 관심이 점차 커지고 있다. 현재 실용화 되어 있는 태양전지는 실리콘 기반 태양전지인데, 제조비용이 큰 단점이 부각되고 있으며 이에 따라 이의 단점을 개선하기 위한 노력과 동시에 실리콘 기반 태양전지를 대체하려는 시도가 이루어지고 있다. 이중 실리콘 기반 태양전지를 대체할 후보로 페로브스카이트 태양전지가 큰관심을 받고 있는데, 그 이유는 높은 광전 변환 효율, 저렴한 제조비용, 유연한 형태로의 제조 가능성 때문이다. 그러나 현재 보고되고 있는 페로브스카이트 태양전지는 장기적 안정성이 떨어지며, 또 납으로 인해 신체에 유해하다는 큰단점을 가지고 있다. 본 리뷰에서는 페로브스카이트 태양전지의 장기적 안정성을 높이는 방안들 그리고 환경적으로 유해한 납을 사용하지 않는 방안들의 최신 연구 방향 동향에 관하여 살펴보았다.

좌심실 혈류 소용돌이 분석을 통한 새로운 심장기능 평가지표의 개발

송재관 대한내과학회 2011 대한내과학회 추계학술대회 Vol.2011 No.-

좌심실 혈류 소용돌이 분석을 통한 새로운 심장기능 평가지표의 개발

송재관 대한내과학회 2011 대한내과학회 추계학술대회 Vol.2011 No.2

수열합성법으로 제막한 MoO₃ 나노 구조체를 정공수송층으로 갖는 페로브스카이트 태양전지 특성분석

송재관,안준섭,한은미,Song, Jae-Kwan,Ahn, Joon-Sub,Han, Eun-Mi 한국재료학회 2020 한국재료학회지 Vol.30 No.2

MoO₃ metal oxide nanostructure was formed by hydrothermal synthesis, and a perovskite solar cell with an MoO₃ hole transfer layer was fabricated and evaluated. The characteristics of the MoO₃ thin film were analyzed according to the change of hydrothermal synthesis temperature in the range of 100 ℃ to 200 ℃ and mass ratio of AMT : nitric acid of 1 : 3 ~ 15 wt%. The influence on the photoelectric conversion efficiency of the solar cell was evaluated. Nanorod-shaped MoO₃ thin films were formed in the temperature range of 150 ℃ to 200 ℃, and the chemical bonding and crystal structure of the thin films were analyzed. As the amount of nitric acid added increased, the thickness of the thin film decreased. As the thickness of the hole transfer layer decreased, the photoelectric conversion efficiency of the perovskite solar cell improved. The maximum photoelectric conversion efficiency of the perovskite solar cell having an MoO₃ thin film was 4.69 % when the conditions of hydrothermal synthesis were 150 ℃ and mass ratio of AMT : nitric acid of 1 : 12 wt%.