초전도 NMR-CT의 영상 원리 및 그 응용

조장희 대한의용생체공학회 1986 의공학회지 Vol.7 No.2

Microspheres are expected to be applied to biomedical areas such as solid-phase immunoassays, drug delivery systems, immunomagnetic cell separation. To synthesize microspheres for biomedical application, "two stage shot growth method" was developed. The uniformity ratio of synthesized microspheres was always smaller than 1.05. And the surface charge density (or the number of ionizable functional groups) of the microspheres synthesized by "two stage shot growth method" was 6~13 times higher than that of the microspheres synthesized by conventional seeded batch copolymerization. As a previous step for biomedical application, adsorption experiments of bovine albumin on microspheres were carried out under various conditions. The maximum adsorbed amount was obtained in the neighborhood of pH 4.5. Isoelectric point of bovine albumin is pH 5.0, so experimental result shows that it shifted to acid area. The adsorption isotherm was obtained, the plateau region was always reached at 2.Og/L (bulk concentration of bovine albumin).The effect of the kind and the amount of surface functional group was also examined.p was also examined.

Fimasartan attenuates renal ischemia-reperfusion injury by modulating inflammation-related apoptosis

조장희,최순윤,류혜명,오은주,육주민,안지선,정희연,최지영,박선희,김찬덕,김용림 대한약리학회 2018 The Korean Journal of Physiology & Pharmacology Vol.22 No.6

Fimasartan, a new angiotensin II receptor antagonist, reduces myocyte damage and stabilizes atherosclerotic plaque through its anti-inflammatory effect in animal studies. We investigated the protective effects of pretreatment with fimasartan on ischemia-reperfusion injury (IRI) in a mouse model of ischemic renal damage. C57BL/6 mice were pretreated with or without 5 (IR-F5) or 10 (IR-F10) mg/kg/day fimasartan for 3 days. Renal ischemia was induced by clamping bilateral renal vascular pedicles for 30 min. Histology, pro-inflammatory cytokines, and apoptosis assays were evaluated 24 h after IRI. Compared to the untreated group, blood urea nitrogen and serum creatinine levels were significantly lower in the IR-F10 group. IR-F10 kidneys showed less tubular necrosis and interstitial fibrosis than untreated kidneys. The expression of F4/80, a macrophage infiltration marker, and tumor necrosis factor (TNF)-α, decreased in the IR-F10 group. High-dose fimasartan treatment attenuated the upregulation of TNF-α, interleukin (IL)-1β, and IL-6 in ischemic kidneys. Fewer TUNEL positive cells were observed in IR-F10 compared to control mice. Fimasartan caused a significant decrease in caspase-3 activity and the level of Bax, and increased the Bcl-2 level. Fimasartan preserved renal function and tubular architecture from IRI in a mouse ischemic renal injury model. Fimasartan also attenuated upregulation of inflammatory cytokines and decreased apoptosis of renal tubular cells. Our results suggest that fimasartan inhibited the process of tubular injury by preventing apoptosis induced by the inflammatory pathway.

최근 자기공명 의료영상기기의 발전 ( Recent Developments in Magnetic Resonance Imaging )

조장희,노용만,정순철,박세혁,문치웅 대한전자공학회 1994 대한전자공학회 학술대회 Vol.1994 No.5

의료영상진단기의 현황과 전망

조장희 대한의용생체공학회 1989 의공학회지 Vol.10 No.2

A new method of digital image analysis technique for discrimination of cancer cell was presented in this paper. The object image was the Thyroid eland cells image that was diagnosed as normal and abnormal (two types of abnormal: follicular neoplastic cell, and papillary neoplastic cell), respectively. By using the proposed region segmentation algorithm, the cells were segmented into nucleus. The 16 feature parameters were used to calculate the features of each nucleus. A9 a consequence of using dominant feature parameters method proposed in this paper, discrimination rate of 91.11% was obtained for Thyroid Gland cells.

시계열 자료를 활용한 제주 관광수요 예측모형의 비교

조장희,최돈승,이태희 한국경영컨설팅학회 2018 경영컨설팅연구 Vol.18 No.2

본 연구는 제주 관광 수요의 시계열 자료를 사용하여 통계적 특성을 확인하고 관광 수요 예측에 적합한 모형을 도출한다. 이를 위해 본 연구는 선행연구에서는 주로 다루고 있는 ARMA 모형과 주기성 변수의 비선형적 특성을 반영하는 GAM을 고려하여 두 결과를 비교한다. 제주 관광객 수의 시계열 자료는 단위근 검정 결과 안정적인 시계열로 나타나 차분을 할 필요가 없어 ARIMA 모형이 아닌 ARMA 모형을 사용한다. 또한 각 모형을 통해 예측한 2017년 동안의 제주 관광 수요의 RMSE 값을 통해 모형의 예측력을 비교한다. 분석 결과에 의하면 선형적인 특성을 보이고 있는 내국인 관광객 수요를 예측할 때는 ARMA 모형의 예측력이 좋았지만, 일정한 추세를 확인하기 어려운 외국인 관광객 수요를 예측할 때는 비선형적 특성을 고려하는 GAM의 예측력이 더 좋은 것으로 나타났다. 이 결과는 제주 관광 특성에 의거하여 중국인을 비롯한 외국인 관광객의 중요성이 강조됨에 따라 정책적 의미를 갖는다. 또한 방법론의 적용 측면에서도 시계열 자료를 이용하여 수요를 예측할 경우 자료를 구성하고 있는 변수를 세분화하여 각각의 시계열 특성을 반영한 모형을 별도로 고려할 필요가 있음을 시사한다. This study forecast the tourism demand of Jeju island using the monthly time series data for the number of tourists(domestic and foreign), and compare the forecasting results and real work using two models, ARMA(or ARIMA) and GAM. The ARMA(or ARIMA) is a more popular to forecast time series data in previous studies, however we consider the non-parametric model(GAM) for adjusting nonlinear characteristics of periodic series, such as a world unobservable trend. We use a ARMA as a reference model, because the number of tourists in Jeju shows a stable time series after the unit root test. We also forecast using GAM, and compare the predictive power of the model through the RMSE value of tourist demand for 2017 in Jeju. The results show that the ARMA model has a good predictive power for forecasting the domestic demand, but the predictive power of the GAM is better when forecasting the foreign demand. And it give a important political implication about changing foreign tourism policy in a bid for Chinese tourists. Also, in terms of applying the methodology, it imply a separate consideration of the model that reflects the characteristics of each time series data.

잊을 수 없는 기억

조장희 철학문화연구소 2018 철학과 현실 Vol.119 No.-

Neural Substrates of Hanja (Logogram) and Hangul (Phonogram) Character Readings by Functional Magnetic Resonance Imaging

조장희,김남범,배성봉,지제근,오가와세이지,박찬웅,김영보 대한의학회 2014 Journal of Korean medical science Vol.29 No.10

The two basic scripts of the Korean writing system, Hanja (the logography of the traditionalKorean character) and Hangul (the more newer Korean alphabet), have been used togethersince the 14th century. While Hanja character has its own morphemic base, Hangul beingpurely phonemic without morphemic base. These two, therefore, have substantiallydifferent outcomes as a language as well as different neural responses. Based on theselinguistic differences between Hanja and Hangul, we have launched two studies; first wasto find differences in cortical activation when it is stimulated by Hanja and Hangul readingto support the much discussed dual-route hypothesis of logographic and phonologicalroutes in the brain by fMRI (Experiment 1). The second objective was to evaluate howHanja and Hangul affect comprehension, therefore, recognition memory, specifically theeffects of semantic transparency and morphemic clarity on memory consolidation andthen related cortical activations, using functional magnetic resonance imaging (fMRI)(Experiment 2). The first fMRI experiment indicated relatively large areas of the brain areactivated by Hanja reading compared to Hangul reading. The second experiment, therecognition memory study, revealed two findings, that is there is only a small difference inrecognition memory for semantic transparency, while for the morphemic clarity was muchlarger between Hanja and Hangul. That is the morphemic clarity has significantly moreeffect than semantic transparency on recognition memory when studies by fMRI incorrelation with behavioral study.

자기 공명 영상술의 원리와 최근 연구현황

조장희,김영근 대한전기학회 1989 전기의 세계 Vol.38 No.8

초전도 핵자기공명 영상 시스템

조장희 대한전기협회 1987 대한전기협회지 Vol.- No.128

Struma ovarii and Papillary thyroid cancer with peritoneal carcinomatosis

조장희,김지형 대한내과학회 2021 대한내과학회 추계학술대회 Vol.2021 No.1