길경(桔梗)의 추출조건에 따른 사포닌 함량의 변화

최재석,유대석,최연희,연규환,홍경식,이병회,김혜진,김현기,김은주,노성환,정영철,김영섭,유시용,Choi, Jae-Seok,Yoo, Dae-Seok,Choi, Yeon-Hee,Yon, Gyu-Hwan,Hong, Kyung-Sik,Lee, Byung-Hoe,Kim, Hye-Jin,Kim, Hyun-Ki,Kim, Eun-Ju,Roh, Seong-Hwan,Jeong 한국생약학회 2007 생약학회지 Vol.38 No.2

We investigated the contents of crude saponin in the decoctions of Platycodi Radix prepared by the different extraction processes. Each lyophilized decoctions prepared by the different protocol were suspended in water and partitioned with ethylacetate (EtOAc) and n-butanol (BuOH), which gave the EtOAc fraction, BuOH fraction and the remaining water fraction, respectively. The content of crude saponin, which was estimated as the amount of BuOH fraction, and the HPLC profiles of the BuOH fraction were analyzed, and compared each others. The crude saponin content in the decoctions were increased proportionally to the increment of the extraction time, amount of water, extraction temperature and the number of repetition for extraction. Consequently, the optimized conditions were deduced to be suitable and recommendable for the preparation of Platycodi Radix ; the water amount needed for the extraction be 15-20 volumes to crude material, temperature for extraction be optimal at $85{\sim}100^{\circ}C$, extraction time be more than 5 hours and the repetition of extraction was 2 times.

데이터마이닝을 이용한 학자금 대출 부실 고위험군 예측모형 개발

최재석,한준태,김면중,정진아,Choi, Jae-Seok,Han, Jun-Tae,Kim, Myeon-Jung,Jeong, Jina 한국데이터정보과학회 2015 한국데이터정보과학회지 Vol.26 No.6

We develop the high risk group predictive model for loan default by utilizing the direct loan data from 2012 to 2014 of the Korea Student Aid Foundation. We perform the decision tree analysis using the data mining methodology and use SAS Enterprise Miner 13.2. As a result of this model, subject types were classified into 25 types. This study shows that the major influencing factors for the loan default are household income, national grant, age, overdue record, level of schooling, field of study, monthly repayment. The high risk group predictive model in this study will be the basis for segmented management service for preventing loan default. 본 연구는 한국장학재단의 2012-2014년간 일반 학자금 대출 자료를 활용하여 부실채권 보유 및 신용유의자로 분류될 수 있는 위험요인들을 파악하고, 부실 고위험군 예측모형을 개발했다. 예측모형 개발은 데이터마이닝 방법 중 의사결정나무 분석을 적용하였으며, 분석 패키지는 SAS Enterprise Miner 13.2를 활용했다. 개발된 모형은 25가지의 그룹으로 세분화 했으며, 부실 위험군에 영향을 미치는 주요 요인은 소득분위, 국가장학금 수혜유무, 나이, 연체계좌 보유 이력, 대학구분 (학부/대학원), 전공 계열, 월평균 상환액이 주요 요인으로 나타났다. 본 연구에서 개발된 부실 고위험군 예측모형은 장기연체로 인한 부실채권 발생 및 신용유의자 발생 예방을 위한 세분화된 관리서비스 제공을 위한 기초자료가 될 수 있을 것이다.

천청일저 제주도 경북대학출판회 1966

최재석 (Jae Seok Choi) 한국문화인류학회 1975 韓國文化人類學 Vol.7 No.1

N/A

파로호의 어류상 및 어류군집

최재석 ( Jae Seok Choi ),장영수 ( Young Su Jang ),이광열 ( Kwang Yeol Lee ),김진국 ( Jin Gun Kim ),권오길 ( Oh Kil Kwon ) 한국환경생물학회 2004 환경생물 : 환경생물학회지 Vol.22 No.1

2002년 12월부터 2003년 9월까지 파로호의 어류상 및 어류군집을 조사한 결과는 다음과 같다. 조사된 어류는 충 12과 45종이었다. 한국고유종은 H. mylodon, A. yamatsutae, C. herzi 등 15종 (33.33%)이었다. 우점종은 Z. platypus(72.41%), 아우점종은 H. labeo (9.75%)였고 우세종은 O. uncirostris amurensis(5.98%), Z. temmincki(2.42%), R. brunneus(2.01%), H. olidus(0.88%) 등 이었다. 채집된 어종들의 생체량은 z. platypus 82,863.15g, H. labeo 32,942.63g, O. uncirostris amurensis 27,482.39g, C. carpio 6,502.87g, A. Jαponica 3,022.15g, S. scherzeri 2,711.05g의 순으로 나타났다. 파로호에서 확인된 도입종은 A. japonica, H. eigenmanni, H. olidus, O. masou masou, C. urotaenius, R. giurinus, C. carpio(Israeli type), C. cuvieri, M. salmoides, L. macrochirus의 10종이었다. 이 중 C. carpio(Israeli type), C. cuvieri, M. salmoiodes, L. macrochirus는 국외종이며 A. japonica, H. eigenmanni, H. olidus, O. masou masou, C. urotaenius, R. giurinus는 국내 다른 하천으로부터 도입된 종이다. The ichthyofauna and community structure in Lake Paro, Korea, was investigated from December 2002 to september 2003. During the surveyed period 45 species belonging 12 families were collected. There were 15 Korean endemic species 33.33%, including Hemibarbus mylodon, Acheilognathus yamatsutae and Coreoperca herzi. Dominant species were Zacco platypus (72.41%) and subdominant species were Hemibarbus labeo (9.75%). Also, Opsariichthys uncirostris amurensis (5.98%), Zacco temmincki (2.42%), Rhinogobius brunneus (2.01%) and Hypomesus olidus (0.88%) were numerous. The biomass of collected fishes were Zacco platypus (82,863.15g), Hemibarbus labeo (32,942.63g), Opsariichthys uncirostris amurensis (27,482.39g), Cyprinus carpio (6,502.87g), Anguilla japonica (3,022.15g) and Siniperca scherzeri (2,711.05g). Of the 10 introduced fishes in Lake Faro Cyprinus carpio (Israeli type), Carassius cuvieri, Micropterus salmoides and Lepomis macrochirus were originated form foreign countries but Anguilla japonica, Hemiculter eigenmanni, Hypomesus olidus, Oncorhynchus masou masou, Chaenogobius urotaenius, Rhinogobiusgiurinus were introduced from other native river systems.

춘천호의 어류상과 군집구조

최재석 ( Jae Seok Choi ) 한국환경생물학회 2005 환경생물 : 환경생물학회지 Vol.23 No.2

2003년 8월부터 2004년 4월까지 춘천호의 어류군집 구조를 조사한 결과는 다음과 같다. 조사된 어류는 총 13과 41종 10,821개체이었다. 한국고유종은 어름치 (H. mylodon), 줄납자루 (A. yamatsutae), 가는돌고기 (P. tenuicorpa), 참중고기 (S. variegatus wakiyae), 얼룩동사리 (O. interrupta) 등 16종(39.0%)이었다. 우점종은 빙어 (H. olidus) 30.7%, 아우점종은 누치 (H. labeo) 14.7%였고, 우세종은 피라미 (Z. platypus) 10.6%, 갈겨니 (Z. temminckii) 9.7%, 큰입우럭 (M. salmoides) 4.8%, 밀어 (R. brunneus) 4.3% 등이었다. 채집된 어종들의 생체량은 누치(H. labeo) 34.63kg, 빙어 (H. olidus) 19.01kg, 잉어 (C. carpio) 12.77kg, 끄리 (O. uncirostris amurensis) 11.28kg, 피라미 (Z. platypus) 8.04kg, 백련어 (H. molitrix) 5.80kg, 큰입우럭 (M. salmoides) 4.62kg등의 순으로 나타났다. 춘천호에서 확인된 도입종은 모두 7종이었고, 이 중 떡붕어 (C. cuvieri), 백련어 (H. molitrix), 큰입우럭 (M. salmoides)은 외래도입종이며 뱀장어 (A. japonica), 빙어 (H. olidus), 산천어 (O. masou masou), 꾹저구 (C. urotaenius)는 국내 다른 하천으로부터 이입된 종이다. The ichthyofauna and community structure in the Chuncheon Reservoir, Korea, were investigated from August 2003 to April 2004. The total number of fish caught from the period was 10,821 fish representing 41 species and 13 families. There were 16 Korean endemic species, including Hemibarbus mylodon, Acheilognathus yamatsutae and Odontobutis platycephala. Dominant species was Hypomesus olidus (30.69%) and subdominant species was Hemibarbus labeo (14.70%). Also, Zacco platypus (10.57%), Zacco temminckii (9.66%), Micropterus salmoides (4.81%), Rhinogobeus brunneus (4.28%) and Microphysogobio yaluensis (3.10%) were numerous. The biomass of collected fishes were Hemibarbus labeo (34.63 kg), Hypomesus olidus (19.01 kg), Cyprinus carpio (12.77 kg), Opsariichthys uncirostris amurensis (11.28 kg), Zacco platypus (8.04 kg). Among the 7 introduced fishes in Chuncheon Reservoir Carassius cuvieri, Hypophthalmichthys molitrix and Micropterus salmoides were originated from foreign countries, and others (Anguilla japonica, Hypomesus olidus, Oncorhynchus masou masou and Chaenogobius urotaenius) were introduced from other native river systems.

SpaceNet 위성영상을 이용한 딥러닝 기반 초해상화 연구

최재석(Jae-Seok Choi),김용우(Yongwoo Kim),김문철(Munchurl Kim),최연주(Yeon-Ju Choi),한상혁(Sanghyuck Han) 한국항공우주학회 2018 한국항공우주학회 학술발표회 논문집 Vol.2018 No.11

존슨-라벡 타입 정전척의 물리적 모델링 및 특성 파악

최재석(Jae Seok Choi),유정훈(Jeonghoon Yoo),홍상준(Sang-Joon Hong),김태현(Tae-Hyun Kim),이성진(Sung Jin Lee) 대한기계학회 2005 대한기계학회 춘추학술대회 Vol.2005 No.11

Generally, Johnsen-Rahbek(J-R) type electrostatic chuck(ESC) generates higher attractive force than Coulomb type ESC. The attractive force in J-R type ESC is caused by the high electrical resistance which occurs in contact region between semiconductor wafer and dielectric layer. This research tries the simple geometrical modeling of contact surface and simulates contact resistance, attractive force and response time according to the variation of contact surface shape. In the latter half of this research, the simulation for pin chuck is accomplished using similar surface modeling and the comparison between pin chuck and general flat chuck is made in aspects of the attractive force and the response time.

볼 베어링을 이용한 Linear Motion Guide의 동적 특성에 관한 연구

최재석(Jae Seok Choi),유정훈(Jeong hoon Yoo),이용섭(Yong-sub Yi),김윤영(Yoon Young Kim),이동진(Dong Jin Lee),이성진(Sung Jin Lee) 한국소음진동공학회 2004 한국소음진동공학회 학술대회논문집 Vol.2004 No.5

최적설계법을 이용한 할바 영구자석 배열의 설계

최재석(Jae Seok Choi),유정훈(Jeonghoon Yoo) 대한기계학회 2008 대한기계학회 춘추학술대회 Vol.2008 No.5

This study tries to design Halbach magnet array using numerical optimization techniques based on the two-dimensional finite element analysis. Optimization problems with various objectives are introduced and design variables are defined as the magnetization direction of each element in the design domain. It is interesting that the base magnet array of all optimized results is equivalent to the Halbach array without any exception. The optimal magnet arrays composed of two linear magnet layers are investigated to maximize the magnetic force between magnet layers. The optimization procedure is constructed by using the sequential linear programming and the adjoint variable method.

홍천강의 어류상 및 어류군집

최재석 ( Jae Seok Choi ),김재구 ( Jai Ku Kim ) 한국환경생물학회 2004 환경생물 : 환경생물학회지 Vol.22 No.3

2002년 4월부터 10월까지 홍천강의 어류상 및 어류군집을 조사한 결과는 다음과 같다. 조사된 어종은 모두 11과 52종이었다. 한국고유종은 Rhodeus uyekii, Acheilognathus signifer, A. yamatsutae, coreoleuciscus splendidus, Koreocobitis rotundicaudata, Silurus microdorsalis 등 23종(44%)이었다. 우점종은 Zacco platypus (20.38%)였고, 아우점종은 Z. temmincki (19.62%)였고, 우세종은 Rhynchocypris oxycephalus (8.45%), Pungtungia herzi (8.01%), C. splendidus (6.63%) 등 이었다. 홍천강에서 확인된 도입종은 Carassius cuvieri, Lepomis macrochirus, Micropterus salmoides, Anguilla japonica, Gymnogobius urotaenia, Rhinogobius giurinus 등 6종이었다. 이 중 C. cuvieri, L. macrochirus, M. salmoides는 국외종이며 A. japonica, G. urotaenia, R. giurinus는 국내 다른 하천으로부터 도입된 종이다. 어류의 분포에 따라, 홍천강의 어류군집은 주성분 분석(PCA)에 의해 4개의 군집으로 나누어졌다. The ichthyofauna and community structure in Hongcheon river, Korea, was investigated from April to October 2002. During the surveyed period, 52 species belonging 11 families were collected. There were 23 Korean endemic species (44.23%), including Rhodeus uyekii, Acheilognathus signifier, A. yamatsutae, Coreoleuciscus splendidus, Koreocobitis rotundicaudata and Silurus microdorsalis. Dominant species were Zacco platypus (20.38%), and subdominant species were Z. temmincki (19.62%). Also, Rhynchocypris oxycephalus (8.45%), Pungtungia herzi (8.01%), C. splendidus (6.63%) were numerous. Of the 6 introduced fishes in Hongcheon river Carassius cuvieri, Lepomis macrochirus and Micropterus salmoides were originated from foreign countries but Anguilla japonica, Gymnogobius urotaenia, Rhinogobius giurinus were introduced from other native river systems. According to the fish distribution, the fish community of Hongcheon river was divided into 4 groups by principle component analysis (PCA).