하이드록시프로필화 쌀 전분의 이화학적 특성

최현욱,구혜진,김종태,황성연,김동섭,최성원,허남윤,백무열,Choi, Hyun-Wook,Koo, Hye-Jin,Kim, Chong-Tai,Hwang, Seong-Yun,Kim, Dong-Seob,Choi, Sung-Won,Hur, Nam-Youn,Baik, Moo-Yeol 한국식품과학회 2005 한국식품과학회지 Vol.37 No.1

쌀 전분에 propylene oxide(PO)를 단계별(전분 공형분 대비 2-12%)로 20시간과 24시간 반응시켜 하이드록시프로필화 쌀 전분을 제조하고, 변성된 쌀 전분의 용해도, 팽윤력, RVA, DSC 특성을 연구하였다. 팽윤력은 일반 쌀 전분 보다 낮은 온도에서 증가되기 시작하였으나 높은 경향을 보였으며, 하이드록시프로필화 쌀 전분이 일반 쌀 전분보다 완만한 상승을 나타내었다. 용해도는 하이드록시프로필화 쌀 전분이 일반 쌀 전분보다 낮은 결과를 나타내었고 PO 함량이 높을수록 높아지는 결과를 보였다. RVA 분석결과 PO 함량이 높을수록 pasting temperature와 peak time이 낮아졌고 최고 점도는 하이드록시프로필화 쌀 전분이 일반 쌀 전분보다 낮고 holding strength는 높은 경향을 나타내고 breakdown의 경우 반응시간이 24시간이 20시간보다 낮은 경향을 보였으며 Setback은 24시간 반응시킨 처리구들이 일반 쌀 전분보다 낮은 것으로 나타났다. DSC분석결과 PO 함량이 높을수록 To, Tp, Tc, ${\Dalta}H$가 감소하였다. 따라서 하이드록시프로필화 쌀 전분의 경우 전분입자내의 intemal bond가 하이드록시프로필기에 의해 약해져서 호화가 쉽게, 즉 낮은 온도에서 일어나는 것으로 판단되었고 최대 팽윤력, breakdown에서 옥수수 전분과는 다른 결과를 나타내어 전분의 종류에 따라 같은 변성 처리라고 하더라도 다른 결과를 나타낼 수 있다는 사실이 확인되었다. Physicochemical properties of hydroxypropylated rice starches were investigated. Swelling power of hydroxypropylated rice starch increased at relatively lower temperature than native rice starch. Solubility of hydroxypropylated rice starch was lower (1.9-13.4%) than that of native rice starch (2.2-13.8%), and increased with increasing amount of propylene oxide. Pasting temperature ($66.2-70.8^{\circ}C$) and peak viscosity (2,843-3,395cp) of hydroxypropylated rice starch were lower than those of native starch ($71.6^{\circ}C,\;3,976\;cp$) and decreased with increasing amount of propylene oxide, regardless of reaction time. DSC thermal transitions of hydroxypropylated rice starches shifted toward lower temperature. Amylopectin-melting enthalpy of hydroxypropylated rice starch decreased (11.8-9.8J/g) with increasing amount of propylene oxide and was lower than that of native starch (11.9 J/g). These results indicate hydroxypropylation lowered swelling power and gelatinization temperatures of rice starch, because internal bonds of rice starch molecules were sterically weaken by substituted hydroxypropyl groups.

대학 골프부 신입생 적응과정에 관한 근거이론 분석

최현욱(Choi, Hyun-Wook),이철원(Lee, Chul-Won),설정덕(Sul, Jeong-Dug) 한국체육과학회 2013 한국체육과학회지 Vol.22 No.3

The purpose of this study was to examine the adaptation process for college golf scholarship of college freshmen. We interviewed six participants and we categorized the context through the theoretical paradigm which are deducted by grounded theoretical approach. The result was as follows. Only for entering a college, the participants started golf but many obstacles such as punishment from seniors give them a hard time. They adapted to the circumstance continually by recognizing the benefits of golf club and self maturity. Resultingly expecting the future, they contented with their major and prepared for a job and licenses. This study had the meaning that suggests a comprehensive reference for the future study of adaptation to golf scholarship of college freshmen.

식품 : 가교화 쌀 전분의 이화학적 특성

최현욱 ( Hyun Wook Choi ),정구민 ( Koo Min Chung ),김정호 ( Chung Ho Kim ),문태화 ( Tae Hwa Moon ),박천석 ( Cheon Seok Park ),백무열 ( Moo Yeol Baik ),( Dong Seob Kim ) 한국응용생명화학회 2006 Applied Biological Chemistry (Appl Biol Chem) Vol.49 No.1

골프참여자의 여가활동 관여도가 여가제약 협상에 미치는 영향

최현욱(Choi, Hyun-Wook),김형훈(Kim, Hyung-Hoon),이철원(Lee, Chul-Won) 한국체육과학회 2012 한국체육과학회지 Vol.21 No.4

The purpose of this study was to identify the relationship between leisure involvement and leisure constraint negotiation for golf participants in Seoul and Kyung-gi area and to provide the preliminary data, which would help foster golf participation as a popular leisure activity. In 2011 using cluster random sampling, 356 men and women above the age of 20 who enjoy their leisure time playing golf, were selected for the survey in Seoul and Kyung-gi area. The collected data were analyzed and interpreted by Windows SPSS 18.0 Ver. In order to measure the reliability and validity of the survey results, there were five methods used : exploratory factor analysis, reliability analysis, frequency analysis, after examining the correlation between leisure involvement and sub-factors of leisure constraint negotiation, Multiple Linear Regression was performed between the two variables. The followings are outcomes obtained from the procedures. First, leisure involvement have been discovered to have a negative influence on the changing leisure aspiration. Second, leisure involvement have been discovered to have a positive influence on the interpersonal relations. Third, leisure involvement have been discovered to have a positive influence on the charging energy. Fourth, leisure involvement have been discovered to have a positive influence on the controlling intensity of an activity. Fifth, leisure involvement have been discovered to have a positive influence on the skills acquisition. Sixth, leisure involvement have been discovered to have a positive influence on the time management.

대학생의 여가활동 유형이 여가강박과 지속적 참여에 미치는 영향

최현욱(Choi, Hyun-Wook),이철원(Lee, Chul-Won),설정덕(Sul, Jeong-Dug) 한국체육과학회 2013 한국체육과학회지 Vol.22 No.6

The purpose of this study was to verify the influence of the type of leisure activity for university students on leisure obsession and intention of continuous, The study conducted a research survey through purposive selection aimed at visitors of 6 ski resorts in Seoul and Gyunggi from September, 2013 during 2 weeks. 430 questionnaires distributed and 409 were selected as final valid sampling by removing 21 questionnaires that have insufficient answers. Then data were analyzed through frequency analysis, exploratory factor analysis, reliability analysis, correlation analysis, and multiple regression analysis using SPSS Windows ver. 20.0. The results were as follows. First, participants in culture and art tourism, leisure worry and leisure regret dimensions of leisure obsession have a significant effect on intention of continuous. Second, participants in sport activity, leisure worry and leisure comparison dimensions of leisure obsession have an influence on intention of continuous. Third, participants in rest and entertainment activity, leisure worry and leisure comparison dimensions of leisure obsession have a significant influence on intention of continuous.

대학생의 건전한 여가형태로서 스키활동 참여에 관한 연구

최현욱(Hyun-Wook Choi) 한국엔터테인먼트산업학회 2017 한국엔터테인먼트산업학회논문지 Vol.11 No.3

본 연구는 대학생의 스키활동 몰입경험, 자아존중감 및 여가태도의 영향력 관계를 실증적으로 분석하기 위하여 외·내생 변수간의 구조적 인과관계를 분석하였다. 조사대상은 2016년 12월~2017년 2월까지 강원도 지역의 스키장을 직접 방문하여 스키활동 참여자 388명을 표집하였으며 통계프로그램을 이용하여 구조방정식(SEM: structural equation modeling) 모형을 도출하였으며 다음과 같은 결론을 도출하였다. 첫째, 대학생의 스키활동을 참여를 통하여 획득된 몰입경험은 자아존중감에 유의한 정(+)적 영향을 미쳤다. 둘째, 대학생의 스키활동을 참여를 통하여 획득된 몰입경험은 여가태도에 유의한 정(+)적 영향을 미쳤다. 셋째, 대학생의 스키활동 참여를 통하여 획득된 자아존중감은 여가태도에 유의한 정(+)적 영향을 미쳤다. 이상의 결론을 종합해 볼 때 대학생의 스키활동 참여를 통한 몰입경험은 자아존중감과 여가태도에 긍정적 영향을 미칠 수 있는 주요변인이라 할 수 있겠다. The purpose of this study is to analyze the structural causality between external and internal variables in order to analyze empirically the influence of college students’ experience of ski activities, self - esteem and leisure attitude. The subjects of the survey were 388 people who skied from December 2016 to February 2017 and visited the ski area of G angwon province. The structural equation modeling (SEM) model was derived using statistical program. Conclusions were drawn. First, the flow experiences obtained through the participation of university students’ ski activities had a positive (+) effect on self – esteem. Second, the flow experiences obtained through the participation of university students’ ski activities had a positive (+) effect on leisure attitude. Third, the self - esteem obtained through college students’ participation in ski activities had a positive (+) effect on leisure attitude. The results of this study suggest that the experience of flow through participation in skiing activities of college students is a major factor that can positively affect self - esteem and leisure attitude.

대형병원의 온라인 진료예약 사용성 평가 연구

최현욱(Choi, Hyun wook),김승인(Kim, Seung In),윤원경(Yoon, Won Kyoung) 한국디지털디자인협의회 2014 디지털디자인학연구 Vol.14 No.1

국내 대형병원의 경우 제공해야 하는 콘텐츠나 여러 가지 부가서비스가 방대해 짐에 따라 사용자가 빠르고, 편안하게 병원 온라인 시스템을 사용하도록 하는 것이 절실히 필요하다. 따라서 본 연구는 이러한 병원 온라인서비스 중 병원에서 사용자가 가장 빈번하게 사용하는 온라인 예약시스템을 연구하였다. 연구 방법으로는 피실험자를 설정하여 직접 병원 온라인 예약 서비스에 대한 사용성평가를 실시하였다. 사용성평가는 병원 온라인시스템에서 가장 시급한 태스크를 선정 하고 공정한 검사를 위해 2병원을 번갈아 가며 태스크에 따라 사용성평가를 실시하였다. 그 후 곧바로 만족도 조사를 실시하였다. 국내 대형 병원 중 서울대병원과 삼성서울병원에 대한 예약시스템을 개선하고 충족시키기 위한 사항들은 다음과 같다. 첫째, 온라인 예약 서비스를 사용하면서 쉽게 인지하고 예약할 수 있는GUI[graphical user interface] 디자인이 선행되어야 하겠다 . 둘째, 병원의 특성상 진료기록에 대한 철저한 보안으로 환자의 신뢰를 얻을 수 있는 예약시스템 구축이 필요하다. 셋째로 다양한 연령층이 사용하는 시스템인 만큼 일관성 있는 메뉴 사용으로 사용자가 쉽게 인지할 수 있는 예약 시스템 구성이 필요하다. 마지막으로 각 병원들의 특색을 강조한 차별화된 예약 시스템과 콘텐츠를 개발하는 것이 중요하겠다. The day to day development of national health care i Since the national healthcare has gradually developed so far, one of the important success factors for hospital is not only in primary treatment but also in pleasant treatment. In case of large scale hospital, a proper hospital on line service for patients is one of essence to give each patients variety of medical contents and additional service. This study is focusing hospital online booking system ( Here in after called HOBS )since it is one of the most frequently used by patients and related customers. A research to evaluate a hospital usability was conducted through a certain patient to reserve the hospital directly via online booking system. The usability evaluation was carried out after selecting a most urgent task in online booking system and alternately conducted at two different hospitals. Then a satisfaction survey was executed on each task. At this time the HOBS of SNUH and Samsung H among lots of large scale hospitals have been fully reviewed. The resultant ideas to improve their HOBS are summarized as following: First, The GUI [graphical user interface] system design: There are variety of customer on a hospital therefore the GUI should be established for each customer’s easy and fast interface. Second, The reliability of system: The HOBS should have proper manual for customer’s easy and fast access and system should be fully reliable in hardware and software. Third, Economic justification : The HOBS should present moderate payback to customer as well as hospital. Forth, Contingency system; The HOBS should equipped with proper contingency plan and system for secure operation in case of system shutdown or malfunction. Lastly, it is extremely important for each hospital to develop a dedicated HOBS with creative contents in line with each hospital to approach advanced medical care system.

가교화 후 하이드록시프로필화한 복합변성 쌀전분의 이화학적 특성

최현욱 ( Hyun Wook Choi ),홍사훈 ( Sa Hoon Hong ),최성원 ( Sung Won Choi ),김창남 ( Chang Nam Kim ),유승석 ( Seung Seok Yoo ),김병용 ( Byung Yong Kim ),백무열 ( Moo Yeol Baik ) 한국산업식품공학회 2011 산업 식품공학 Vol.15 No.4

Physicochemical properties of dual-modified rice starches, cross-linked (with POCl3) and hydroxypropylated (with propylene oxide) rice starches, were studied. Rice starch was cross-linked using POCl3 (0.005%, 0.02% (v/w)) at 45oC for 2 hr and then hydroxypropylated using propylene oxide (2%, 6%, 12% (v/w)) at 45oC for 24 hr, respectively. Swelling power, solubility, thermal properties (DSC) and pasting properties (RVA) of cross-linked and hydroxypropylated (CLHP) rice starches were determined. Swelling power of CLHP rice starch increased at relatively lower temperature than native rice starch. Solubility of CLHP rice starch was lower than that of native rice starch. Peak viscosity of CLHP rice starch was lower than that of native starch while holding strength and final viscosity were increased with modification. Breakdown value was lower and setback value was higher than native rice starch. DSC thermal transitions of CLHP rice starch shifted toward lower temperature. Amylopectin-melting enthalpy of CLHP rice starch decreased, whereas it was not affected by the amount of POCl3.

원격의료 서비스의 개인정보 침해 시나리오 개발

최현욱 ( Hyun-wook Choi ),김택영 ( Taek-young Kim ),김태성 ( Tae-sung Kim ) 한국정보처리학회 2021 한국정보처리학회 학술대회논문집 Vol.28 No.2

4차 산업혁명 시대가 도래함에 따라 사물인터넷(IoT)이 다양한 산업의 영역에서 활용되고 있다. 특히 IoT 기술 및 서비스를 활용하는 분야 중 하나인 스마트 의료 분야는 최근 소프트웨어 및 네트워크의 연결성이 강화되면서 사이버보안 사고가 급증하고 있다. 따라서 스마트 의료 기기 서비스 개발 단계부터 보안을 고려하여 안전하게 개발하는 것이 필요하며, 서비스 제공시에도 보안을 고려하여 안전하게 관리 및 서비스를 제공하는 것이 필요하다. 이에 본 연구에서는 IoT 서비스 활용 분야 중 스마트 의료 분야에서 원격의료 서비스의 개인정보 침해 요인을 도출하고 이를 토대로 어택트리 기반의 시나리오 분석을 수행하고자 한다.

하이드록시프로필화 후 가교화시킨 복합변성 쌀 전분의 이화학적 특성

최현욱 ( Hyun Wook Choi ),김상갑 ( Sang Kab Kim ),최성원 ( Sung Won Choi ),김창남 ( Chang Nam Kim ),유승석 ( Seung Seok Yoo ),김병용 ( Byung Yong Kim ),백무열 ( Moo Yeol Baik ) 한국산업식품공학회 2011 산업 식품공학 Vol.15 No.4

Physicochemical properties of hydroxypropylated and cross-linked (HPCL) rice starch were investigated. Dual modification of rice starch was carried out by hydroxypropylation using propylene oxide (2, 6, and 12%) and then crosslinking using phosphorus oxychloride (0.005% and 0.02%). Swelling power of dual-modified rice starch increased at lower temperature (60oC) than that of native rice starch (70oC). HPCL rice starch showed slightly lower solubility (1.6-6.1%) than native rice starch (2.2-13.8%). Solubility and swelling power tended to gradually increase with increasing phosphorus oxychloride contents. RVA pasting temperature (66.2-70.8oC) and peak viscosity (160.6- 171.1 RVU) of HPCL rice starch were lower than that of those of native starch (71.3oC, 190.4 RVU) and decreased with increasing propylene oxide concentration. DSC thermal transitions of HPCL rice starches shifted to lower temperature and show less amylopectin melting enthalpy (11.8-9.8 J/g) than that of native rice starch (11.9 J/g). Overall, physicochemical properties of HPCL rice starches were highly dependent on hydroxypropylation rather than crosslinking.