수소화된 비정질 실리콘 n?-p-p? 태양전지에서 최적 기판온도의 결정

이이상(Yi Sang Lee),장진(Jin Jang) 대한전기학회 1987 대한전기학회 학술대회 논문집 Vol.1987 No.7

콘빔 전산화단층촬영(CBCT) 시스템에서 기계적 오류에 관한 연구

이이성(Yi-Seong Lee),유은정(Eun-Jeong Yoo),김승근(Seung-Keun Kim),최경식(Kyoung-Sik Choi),이정우(Jeong-Woo Lee),서태석(Tae-Suk Suh),김정구(Joeng-Koo Kim) 대한방사선과학회(구 대한방사선기술학회) 2013 방사선기술과학 Vol.36 No.2

본 연구는 선형가속기의 회전불균형의 영향으로 발생 되는 CBCT 영상의 setup 오차 변화를 분석하여, 회전불균형에 대한 정도관리의 필요성을 연구 하였다. CBCT 시스템의 3차원 체적영상모드를 이용하여 360° 회전과 180° 회전으로 Catphan503 팬텀과 균질 팬텀의 3차원 영상을 획득하였고, setup 오차를 측정하기 위해 나선형 CT의 기준영상과 함께 비교 분석 하였다. 표준 정도관리의 절차를 시행하여 정상적인 상태를 확인하고, 임의적으로 갠트리의 회전균형을 조절한 후, 균형상태와 불균형상태의 각각 CBCT 영상에 대하여 X, Y, Z, Roll, Pitch, and Yaw의 6차원적 관점에서 setup 오차를 측정하고 분석하였다. Setup 오차의 변화율은 갠트리 회전균형의 조정 전·후를 확인한 결과, 직교 좌표계는 360°의 회전에서 X축 방향으로 0.6 mm, Y축 방향으로 0.5 mm, Z축 방향으로 0.5 mm의 최대 변화율을 보였다. 180°의 회전은 X축 방향으로 0.9 mm, Y축 방향은 0.2 mm, Z축 방향은 0.3 mm의 최대 변화율을 보였다. 또한 회전 변환계는 회전 불균형이 커질수록 평균적인 값의 차이가 점점 증가하였고, 최대값은 1.1°를 나타내었다. 영상의 분해능은 균형 조정 전ㆍ후 영상분석 툴에서 2 lp/㎝ 차이를 나타내었다. CBCT 시스템의 정도관리는 기준 권고안을 만족하였다. 갠트리의 회전 불균형이 클 때, setup 오차의 직교좌표계의 변화는 크지 않았으나, 회전 변환계의 변화율은 기준 권고 값인 1°에 해당하는 값과 초과하는 1.1°를 나타내었다. 이는 갠트리의 불균형이 setup 오차에 영향을 미치는 것을 알 수 있었으며, 또한 회전 변환계의 setup 오차에 대한 6차원적인 보정이 더욱 요구됨을 알 수 있다. 그러므로 정확하고 정교한 영상유도 방사선치료를 수행하기 위해서는 갠트리의 균형도를 확인해야 하며, 정도관리 항목으로 추가되어야 한다고 사료되어진다. This study investigated the rate of setup variance by the rotating unbalance of gantry in image-guided radiation therapy. The equipments used linear accelerator(Elekta Synergy ™, UK) and a three-dimensional volume imaging mode(3D Volume View) in cone beam computed tomography(CBCT) system. 2D images obtained by rotating 360°and 180° were reconstructed to 3D image. Catpan503 phantom and homogeneous phantom were used to measure the setup errors. Ball-bearing phantom was used to check the rotation axis of the CBCT. The volume image from CBCT using Catphan503 phantom and homogeneous phantom were analyzed and compared to images from conventional CT in the six dimensional view(X, Y, Z, Roll, Pitch, and Yaw). The variance ratio of setup error were difference in X 0.6 ㎜, Y 0.5 ㎜ Z 0.5 ㎜ when the gantry rotated 360° in orthogonal coordinate. whereas rotated 180°, the error measured 0.9 ㎜, 0.2 ㎜, 0.3 ㎜ in X, Y, Z respectively. In the rotating coordinates, the more increased the rotating unbalance, the more raised average ratio of setup errors. The resolution of CBCT images showed 2 level of difference in the table recommended. CBCT had a good agreement compared to each recommended values which is the mechanical safety, geometry accuracy and image quality. The rotating unbalance of gentry vary hardly in orthogonal coordinate. However, in rotating coordinate of gantry exceeded the ±1° of recommended value. Therefore, when we do sophisticated radiation therapy six dimensional correction is needed.

폐암환자에서 근치적 폐절제술 후 말초혈액 단핵구의 NK 활성도의 변화

이이형(Yi Hyeong Lee),김세규(Se Kyu Kim),장준(Joon Chang),김성규(Sung Kyu Kim),이원영(Won Young Lee) 대한내과학회 1994 대한내과학회지 Vol.46 No.6

N/A Objectives: Natural killer (NK) cells are thought to serve as a first line of defense against tumor cells. The NK activities of peripheral blood mononuclear cells and pulmonary lymphocytes in patients with lung cancer were known to be decreased compared to those of healthy controls. The NK activity was reported to be restored after curative surgery, and decreased again in recurrent cases. We performed this study to investigate the change of the NK activity after curative surgery and to elucidate the relationship between the NK activity and clinical course of the patients. Methods: We studied the changes of the NK activities of peripheral blood mononuclear cells in 22 patients with lung cancer before and after curative surgery. Results are shown as % lysis of K562 cells at 50: 1 effector: target (E: T) ratio. Results: 1) The mean NK activity of peripheral blood mononuclear cells in patients with lung cancer (29.0±14.9%) was significantly lower than that of healthy controls (37.8±25.5%), and there was no significant difference according to cell type and stage. 2) The NK activity after curative surgery (40.7±20.7%) was significantly increased compared with that before surgery (29.0±14.9%) (p<0.05). 3) The NK activity after 1 week of surgery (31.1±9.6%) was not significantly increased compared with that of before surgery, but that was increased significantly after 1 month (46.9±21.1%), and was maintained high after 3 months (39.2±20.1%) in patients without recurrence (p<0.05). Conclusion: From our results, we concluded that NK activity of the patients with lung cancer is restored after curative surgery.

斥邪衛正論의 批判的 檢討

李離和(Yi I-hoa) 한국사연구회 1977 한국사연구 Vol.18 No.-

고객가치, 신뢰 및 지속적 사용의도의 관계에 대한 연구 : 인포메이션 앱을 중심으로

이이진 ( Lee Yi-jin ),염창선 ( Yum Chang-sun ) 한국경영공학회 2020 한국경영공학회지 Vol.25 No.1

In this study, As competition grows among applications, application operator is showing great interest in customer value and trust for the success of the business. In this study, the model with the customer value factors influencing trust in mobile information applications is suggested. The result of this study shows that customer value factors such as utility and personalization of utilitarian value, enjoyment and aesthetics of hedonic value, self-esteem of social value have significantly positive influence on trust. Trust has significantly positive influence on continued use intention. The results of the study can be used practically for the successful implementation and operation of information applications.

Manufacturing a Functional Bolus Using a 3D printer in Radiation Therapy

이이성(Yi-Seong Lee),김정구(Jeong-Koo Kim) 대한방사선과학회(구 대한방사선기술학회) 2020 방사선기술과학 Vol. No.

Commercial plate bolus is generally used for treatment of surface tumor and required surface dose. We fabricated 3D-printed bolus by using 3D printing technology and usability of 3D-printed bolus was evaluated. RT-structure of contoured plate bolus in the TPS was exported to DICOM files and converted to STL file by using converting program. The 3D-printed bolus was manufactured with rubber-like translucent materials using a 3D printer. The dose distribution calculated in the TPS and compared the characteristics of the plate bolus and the 3D printed bolus. The absolute dose was measured inserting an ion chamber to the depth of 5 ㎝ and 10 ㎝ from the surface of the blue water phantom. HU and ED were measured to compare the material characteristics. 100% dose was distributed at Dmax of 1.5 ㎝ below the surface when was applied without bolus. When the plate bolus and 3D-plate bolus were applied, dose distributed at 0.9 ㎝ and 0.8 ㎝ below the surface of the bolus. After the comparative analysis of the radiation dose at the reference depth, differences in radiation dose of 0.1 ~ 0.3% were found, but there was no difference dose. The usability of the 3D-printed bolus was thus confirmed and it is considered that the 3D-printed bolus can be applied in radiation therapy.

해녀콩의 잎원형질체와 잎절편에서 아르기닌과 L-Canavanine의 흡수

이이,권영명,Lee, Yi,Kwon, Young-Myung 생화학분자생물학회 1993 한국생화학회지 Vol.26 No.3

해녀콩(Canavalia lineata) 잎에서 분리한 원형질체에서 아르기닌의 흡수를 측정하였다. 아르기닌 홉수의 kinetics는 두 phase를 갖는 것으로 나타났고, $K_m$은 각각 0.03 mM(phase I)과 5.5 mM(phase II)이였다. Phase I에서 아르기년의 홉수를 호모아르기닌, L-canavanine, 리신은 경쟁적으로, 히스티딘, 류신은 경쟁과 비경쟁의 혼합 형태로, 이소류신은 무경쟁적으로 억제하였으나, 아스파르트산, 글루탐산, D-아르기닌, D-오르니틴은 억제하지 않았다. 아르기닌의 흡수는 2,4-dinitrophenol, carbonyl cyanide m-chlorophenylhydrazone, N,N'-dicyclohexyl-carbodiimide, orthovanadate에 의하여 저해되었으며, fusicoccin에 의해서는 크게 촉진되었다. 아르기닌 흡수의 최적 pH는 6.5였다. 해녀콩 잎절편에서 L-canavanine의 흡수는 0.2-4mM 범위에서 단일 phase로 나타났으며, $K_m$은 0.56 mM이었다. L-Canavanine 흡수에서 아르기닌은 경쟁적인 억제를 보였으며, 다른 아미노산들에 의한 저해 패턴은 원형질체에 의한 아르기닌 흡수의 경우와 유사하였다. L-Arginine uptake was studied in the protoplasts isolated from the leaves of Canavalia lineata. A kinetic analysis of the L-arginine uptake showed that the uptake was biphasic. The $K_m$ value for phase I was 0.03 mM, and for phase II was 5.5 mM. At phase I, L-homoargi-nine, L-canavanine, L-ornithine, L-lysine, L-histidine, L-leucine, and L-isoleucine inhibited the uptake, but L-aspartic acid, L-glutamic acid, D-arginine, and D-ornithine did not show any inhibitory effect. Among the inhibitory amino acids, L-homoarginine, L-canavanine, and L-lysine exerted a competitive inhibition. However, L-isoleucine exerted an uncompetitive inhibition, and L-histidine and L-leucine exerted an inhibition intermediate between competitive and noncompetitive ones. In addition, L-arginine uptake was pH-dependent with optimum pH of 6.5, and it was inhibited by 2,4-dinitrophenol, carbonyl cyanide m-chlorophenyl-hydrazone, N,N'-dicyclohexylcarbodiimide, and orthovanadate. However, it was stimulated significantly by fusicoccin. L-Canavanine uptake by slices of C. lineata leaves was also studied. A kinetic analysis of the L-canavanine uptake from 0.2 mM to 4 mM showed that the uptake was monophasic, and its $K_m$ value was 0.56 mM. The additional amino acids inhibited L-canavanine uptake by the leaf slices in the same way that those did L-arginine uptake by the protoplasts, and L-arginine inhibited the L-canavanine uptake competitively.

원저 : 폐절제술 후 폐환기능의 변화에 대한 장기 추적관찰

이이형 ( Yi Hyeong Lee ),김세규 ( Se Kyu Kim ),장준 ( Joon Chang ),정경영 ( Kyung Young Chung ),안철민 ( Chul Min Ahn ),김성규 ( Sung Kyu Kim ),이원영 ( Won Young Lee ) 대한결핵 및 호흡기학회 1993 Tuberculosis and Respiratory Diseases Vol.40 No.6

나파온을 이용하여 패키징된 무효소 혈당센서의 혈장 및 전혈에서의 특성 평가

이이재(Yi-Jae Lee),김정두(Jung-Doo Kim),박재영(Jae-Yeong Park) 대한전기학회 2008 대한전기학회 학술대회 논문집 Vol.2008 No.7(초록집)

과거사 청산과 이 시대인의 사명

이이화(Lee Yi-Wha) 부산경남사학회 2008 역사와 경계 Vol.67 No.-