웅담(熊膽) 및 우루소데옥시콜린 산(酸)의 항(抗)알레르기 효과(效果)에 관(關)한 실험적(實驗的) 연구(硏究)

정재환,이진용,김덕곤,정규만,Jeong Jae-Hwan,Lee Jin-Yong,Kim Deok-Gon,Jeong Gyu-Man 대한한방소아과학회 1996 대한한방소아과학회지 Vol.10 No.1

Experimental studies were done to research the effects of the Ursi fel and the UDCA on the anti-allergic effects. The results were obtained as follows: 1) In the experimental effects of the Ursi fel and the UDCA on the vascular permeability responses to intradermal Serotonin, though both of the Ursi fel and UDCA revealed the significant effect, the Ursi fel had stronger effect than the UDCA. 2) In the provocative effects of the Ursi fel and the UDCA on the vascular permeability responses to intradermal Histamin, though both of the Ursi powfel and UDCA showed the significant effect, the Ursi fel had moreerful effect than the UDCA. 3) In the 48 hours homologous passive cutaneous anaphylaxis provoked by the IgE-like antibody against white egg albumin, though both of the Ursi fel and UDCA revealed significant effect, the Ursi fel had stronger effect than the UDCA. 4) In the delayed type hypersensitivity response to Picryl Chlorede, though both of the Ursi fel and UDCA were proved to be effective significantly the Ursi fel showed stronger effect. 5) In the delayed type hypersensitivity responses to Sheep red blood cell, the Ursi fel revealed the significant effect, though the UDCA has no significant effect. According to above results, the Ursi fel was approved it could be used widely as antiallergic drug for immediate and delayed type allergic diseases. Although the UDCA revealed efficacy in immediated type allergic diseases, it had less powerful effects than the Ursi fel and it showed no effects in some experiment of delayed type allergy, so it would be difficult to be used clinically.

국가 물 관리를 위한 한국형 토양수분량 관측시스템 설계

정재환,최민하,Jeong, Jae-Hwan,Choe, Min-Ha 한국수자원학회 2018 물과 미래(한국수자원학회지) Vol.51 No.6

반도체 생산라인에서 SA를 이용한 최적 WIP수준과 버퍼사이즈 결정

정재환,장세인,이종환,Jeong, Jaehwan,Jang, Sein,Lee, Jonghwan 한국반도체디스플레이기술학회 2021 반도체디스플레이기술학회지 Vol.20 No.3

The domestic semiconductor industry can produce various products that will satisfy customer needs by diversifying assembly parts and increasing compatibility between them. It is necessary to improve the production line as a method to reduce the work-in-process inventory (WIP) in the assembly line, the idle time of the worker, and the idle time of the process. The improvement of the production line is to balance the capabilities of each process as a whole, and to determine the timing of product input or the order of the work process so that the time required between each process is balanced. The purpose of this study is to find the optimal WIP and buffer size through SA (Simulated Annealing) that minimizes lead time while matching the number of two parts in a parallel assembly line with bottleneck process. The WIP level and buffer size obtained by the SA algorithm were applied to the CONWIP and DBR systems, which are the existing production systems, and the simulation was performed by applying them to the new hybrid production system. Here, the Hybrid method is a combination of CONWIP and DBR methods, and it is a production system created by setting new rules. As a result of the Simulation, the result values were derived based on three criteria: lead time, production volume, and work-in-process inventory. Finally, the effect of the hybrid production method was verified through comparative analysis of the result values.

기계학습 기반 고해상도 토양수분 복원을 위한 Sentinel-1 SAR의 자립형 활용성 평가

정재환,조성근,전현호,이슬찬,최민하,Jeong, Jaehwan,Cho, Seongkeun,Jeon, Hyunho,Lee, Seulchan,Choi, Minha 대한원격탐사학회 2022 大韓遠隔探査學會誌 Vol.38 No.5

기후변화로 인한 가뭄, 홍수, 산불, 산사태 등 자연재해의 위협이 증가함에 따라, 합성개구레이더(Synthetic Aperture Radar, SAR)와 같이 고해상도 토양수분 복원에 대한 사회적 수요도 증가하고 있다. 하지만 국내 환경은 산림 지형의 비율이 높아, 식생과 지형의 영향을 크게 받는 SAR 자료에서 토양수분을 복원하는데 많은 어려움을 겪고 있다. 이에 본 연구에서는 기계학습의 일종인 인공신경망(Artificial Neural Network, ANN) 기법을 활용하여, Sentinel-1 SAR 영상의 자립형 활용성을 평가하였다. Sentinel-1에서 얻을 수 있는 이중편파 산란계수는 토양수분 거동과 유의미한 상관성을 가지고 있음을 확인할 수 있었으며, 다른 위성이나 지점에서 관측된 보조자료를 사용하지 않고도 식생의 효과 등을 보정할 수 있는 자립형 활용 가능성도 확인할 수 있었다. 하지만 각 지점별, 지형 그룹별 특성에 의한 차이가 크게 나타났으며, 특히 산지와 평지에서 학습된 모형을 교차적용하였을 때 토양수분을 제대로 모의할 수 없는 현상이 발생하였다. 또한 이러한 문제를 해결하고자 학습 지점의 수를 늘리는 경우에는 토양수분 복원 모형이 평활화되어 상관계수는 증가하였으나, 지점에서의 오차는 점점 증가하였다. 따라서 고해상도 SAR 토양수분 자료를 광범위하게 적용하기 위해서는 체계적 연구 수행이 선행되어야 하며, 목적에 따른 학습 지점의 선정, 적용 지역의 범위 등을 구체적으로 제한하여 활용한다면 다양한 분야에서 효과적으로 활용할 수 있을 것으로 기대된다. As the threat of natural disasters such as droughts, floods, forest fires, and landslides increases due to climate change, social demand for high-resolution soil moisture retrieval, such as Synthetic Aperture Radar (SAR), is also increasing. However, the domestic environment has a high proportion of mountainous topography, making it challenging to retrieve soil moisture from SAR data. This study evaluated the usability of Sentinel-1 SAR, which is applied with the Artificial Neural Network (ANN) technique, to retrieve soil moisture. It was confirmed that the backscattering coefficient obtained from Sentinel-1 significantly correlated with soil moisture behavior, and the possibility of stand-alone use to correct vegetation effects without using auxiliary data observed from other satellites or observatories. However, there was a large difference in the characteristics of each site and topographic group. In particular, when the model learned on the mountain and at flat land cross-applied, the soil moisture could not be properly simulated. In addition, when the number of learning points was increased to solve this problem, the soil moisture retrieval model was smoothed. As a result, the overall correlation coefficient of all sites improved, but errors at individual sites gradually increased. Therefore, systematic research must be conducted in order to widely apply high-resolution SAR soil moisture data. It is expected that it can be effectively used in various fields if the scope of learning sites and application targets are specifically limited.

농업저수지의 저수량 추정을 위한 Sentinel-1 SAR 영상 기반 수체탐지 기법

정재환,오승철,이슬찬,김진영,최민하,Jeong, Jaehwan,Oh, Seungcheol,Lee, Seulchan,Kim, Jinyoung,Choi, Minha 한국수자원학회 2021 한국수자원학회논문집 Vol.54 No.7

Agricultural water occupies 48% of water demand, and management of agricultural reservoirs is essential for water resources management within agricultural basins. For more efficient use of agricultural water, monitoring the distribution of water resources in agricultural reservoirs and agricultural basins is required. Therefore, in this study, three threshold determination methods (i.e., fixed threshold, Otsu threshold, Kittler-Illingworth (KI) threshold) were compared to detect terrestrial water bodies using Sentinel-1 images for 3 years from 2018 to 2020. The purpose of this study was to evaluate methods for determining threshold values to more accurately estimate the reservoir area. In addition, by analyzing the relationship between the water surface and water storage at the Edong, Gosam, and Giheung reservoirs, water storage based on the SAR image was estimated and validated with observations. The thresholding method for detecting a waterbody was found to be the most accurate in the case of the KI threshold, and the water storage estimated by the KI threshold indicated a very high agreement (r = 0.9235, KGE' = 0.8691). Although the seasonal error characteristics were not observed, the problem of underestimation at high water levels may occur; the relationship between the water surface and the water storage could change rapidly. Therefore, it is necessary to understand the relationship between the water surface area and water storage through ground observation data for a more accurate estimation of water storage. If the use of SAR data through water resources satellites becomes possible in the future, based on the results of this study, it is judged that it will be beneficial for monitoring water storage and managing drought.

인공지능, 수문해석의 미래를 위한 파트너

정재환,조성근,이슬찬,오승철,전현호,김완엽,최민하,Jeong, Jae-Hwan,Jo, Seong-Geun,Lee, Seul-Chan,O, Seung-Cheol,Jeon, Hyeon-Ho,Kim, Wan-Yeop,Choe, Min-Ha 한국수자원학회 2021 물과 미래(한국수자원학회지) Vol.54 No.12

어린이 비만 클리닉 내원환자의 분석(I)

정재환,이진용,김덕곤,Jeong Jae-Hwan,Lee Jin-Yong,Kim Deok-Gon 대한한방소아과학회 1997 대한한방소아과학회지 Vol.11 No.1

AHP 및 Fuzzy 의사결정 모형을 활용한 반도체 장치라인의 CTP 선정 방법론 개발

정재환,김정섭,김여진,이종환,Jeong, Jaehwan,Kim, Jungseop,Kim, Yeojin,Lee, Jonghwan 한국반도체디스플레이기술학회 2021 반도체디스플레이기술학회지 Vol.20 No.2

Cases and studies on the selection method of CTQ are relatively active, but there are few cases or studies on the selection method of CTP which is important in the device industry. In fact, many companies simply select and manage CTP from the point of contact based on their experience and intuition. The purpose of this study is to present an evaluation model and a mathematical decision model for rational and systematic CTP selection to improve the process quality of semiconductor equipment lines. In the evaluation model, AHP (Analytic Hierarchy Process) analysis technique was applied to show objective and quantitative figures, and Fuzzy decision-making model was used to solve the ambiguity and uncertainty in the decision-making process. Decision Value (DV) was presented. The subjects were 22 process factors managed in the Plating Process that the representative equipment line can do. As a result, the evaluation model proposed in this study can support more efficient and effective decision-making for process quality improvement by more objectively measuring the problem of subjective CTP selection in manufacturing sites.

어린이 성장(成長)에 대(對)한 한의학적(韓醫學的) 고찰(考察)

정재환,정규만,Jeong, Jae-Hwan,Jeong, Gyu-Man 대한한방소아과학회 1996 대한한방소아과학회지 Vol.10 No.1

접경지역 최적 주민철수 계획수립을 위한 모형 연구

정재환,윤호영,정창순,김경섭,Jung, Jae Hwan,Yun, Ho Yeong,Jeong, Chang Soon,Kim, Kyung Sup 한국재난정보학회 2018 한국재난정보학회 논문집 Vol.14 No.2

Purpose: This research proposes an optimization model for effective evacuation routing and scheduling of civilians near the border area when full-scale war threats heighten. Method: To reflect the reality, administrative unit network is created using Kruscal's Algorithm, Harmony Search, CCRP based on the geographical features, population, and traffic data of real cities, and then, optimal civilian evacuation routes are found. Results: Optimal evacuation routes and schedules are computed by repetitive experiments, and it is found that the scenario that minimizes the average civilian evacuation time is effective for the civilian evacuation plan. Conclusion: By using the civilian evacuation plan this research proposes, at the time of establishing the actual civilian evacuation plan, quantitative analysis is used for the effective plan making rather than only depending. 연구목적: 본 연구는 전면전 위기 고조 시 효율적인 접경지역 주민 철수경로 및 일정수립에 최적화된 모형 제안을 목적으로 한다. 연구방법: 현실 반영을 위해 실제 도시의 지형, 인구, 도로 데이터를 기반으로 Kruscal's Algorithm, Harmony Search, CCRP를 활용하여 행정구역(읍 면 동) 단위 네트워크를 생성한 후, 최적의 주민철수로를 찾는 순서로 실험을 진행한다. 연구결과: 반복실험을 통해 최적의 주민철수 경로 및 스케줄을 산출하였고, 주민 철수시간 평균을 최소화하는 시나리오가 주민철수 계획수립에 효율적이라는 것을 확인하였다. 결론: 본 연구에서 제안하는 주민철수 모형을 활용하면, 주민철수 계획 수립 시 기존의 정성적인 분석에 정량적 분석을 보완하여 보다 효율적인 계획 수립이 가능할 것으로 사료된다.