• 청정기술
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• 제30권3호
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• pp.203-210
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• 2024

본 연구는 초임계 추출법을 이용하여 커피 생두에서 카페인을 효율적으로 제거하면서도 주요 향미 성분인 트리고넬린과 클로로겐산을 보존하는 최적의 조건을 찾고자 하였다. 다양한 전처리 조건과 초임계 추출 조건을 통해 실험한 결과, 수분 함량이 35%인 생두를 열수 불림하였을 때 카페인 추출률이 90.6%로 가장 높았고, 트리고넬린과 클로로겐산의 보존율은 다소 낮아지는 경향을 보였다. 초임계 추출 시간에 따른 실험에서는 시간이 증가함에 따라 카페인 함량이 감소하였고, 온도와 압력이 60 ℃와 40 MPa 일 때의 조건에서 추출한 생두가 카페인 제거와 향미 성분 보존에 가장 효과적이었다. 물의 투입량이 높아짐에 따라 카페인 추출률이 높아졌으나, 향미 성분의 손실도 증가하는 경향이 나타났다. 용매-원료 비가 증가함에 따라 카페인 제거율은 상승하였고, 특히 용매-원료 비가 250인 조건에서 카페인 추출률 91.0%와 트리고넬린 및 클로로겐산 보존율이 각각 99.9% 및 85.9%로 최적의 결과를 보였다.

• 대한화장품학회지
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• 제46권2호
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• pp.179-184
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• 2020

피부를 탄력있고 부드럽게 하는 역할은 각질층에 존재하는 수분량에 의해 좌우된다. 피부 수분량은 냉온풍, 건조환경 등 다양한 환경 변화에 의해 영향을 받음이 알려져 있으나, 개인 피부 차이에 따른 피부 수분량 변화와 회복 정도에 대해서는 많은 연구가 이루어 지지 않은 실정이다. 본 연구에서는 온풍 조건하에서 피시험자들의 피부 수분 탈락 및 회복 정도를 비교 평가하여 새로운 피부 타입을 제시하고, 온풍 조건에서 저하되는 피부 수분량을 개선 시켜주는 효능 물질을 개발하고자 하였다. 온풍 환경 조성을 위해, 건강한 피험자(남: 10 명, 여: 39 명, 25 세 - 63 세)의 전완부에 온풍(30 cm, 40 ℃, 6 m/s)을 30 min 간 피부에 노출시켜, 피부 수분량의 변화를 평가하였다. 26명(남: 4 명, 여: 22 명, 평균 연령: 42.7 ± 9.4)이 온풍 노출 전에 비하여 온풍 노출 후 수분량이 유의하게 감소하며, 노출 후 30 min이 지나도 회복이 되지 않았다. 온풍 노출 후 수분량이 떨어지는 피험자(여: 10 명)를 대상으로 보수력이 높은 크림을 3 주간 전완부에 적용한 이후 동일 온풍 조건하에서 피부 수분량을 측정한 결과, 노출 30 min 후 피부 수분량이 온풍 노출 전 수준으로 회복됨을 확인하였다. 본 연구를 통하여 피부는 건조 조건에서 쉽게 수분을 잃어버리는 피부(탈수형 피부)가 존재하는 것을 확인하였다. 이는 앞으로 화장품 개발을 보습 기능뿐만 아니라, 이러한 환경변화에 따른 피부 수분이 쉽게 빠져나가는 피부(탈수형 피부)의 특성에 맞는 제품의 효능 개발이 필요함을 보여준다.

• 한국유기농업학회지
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• 제25권2호
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• pp.329-344
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• 2017

본 논문은 한국형 무경운 재배 토양에서 유기물 투입과 분할 관수가 고추 생육 및 수량과 토양 화학성, 생물다양성에 미치는 영향을 구명하고자 추진하였다. 시험 후 토양에 화학성을 조사한 결과 토양 pH는 5.6~6.2, 유기물 함량은 $32{\sim}42g\;kg^{-1}$, EC는 $1.0{\sim}2.7dS\;m^{-1}$, 치환성 K은 $0.08{\sim}0.24cmol^+kg^{-1}$, Ca은 $9.5{\sim}12.8cmol^+kg^{-1}$, Mg은 $2.7{\sim}3.2cmol^+kg^{-1}$ 수준이었으며, 유효인산은 $1,011{\sim}1,137mg\;kg^{-1}$ 수준이었다. 무처리에서 토양에 미소동물은 톡토기와 응애류 등 5종 54개체가 포획되었으나, 대두박을 투입한 처리는 9종 271개체가 포획되어 되었다. 토양환경의 지표가 되는 자연도 점수가 대두박 투입 처리는 11점으로 무 투입 5점에 비하여 2배 정도 증가되었다. 대두박 투입은 무 투입에 비하여 고추의 수확과수의 감소로 수량이 감소되는 경향이었다. 그러나 대두박 무 투입 조건에서 표준시비량의 33~66% 수준에서 고추 수량은 증수되었으며 대두박 투입에서는 표준시비량의 33% 수준에서 증수되었다. 2회 분할관수는 1회 전량관수에 비하여 고추의 수확 과수가 12.5~34.9% 증가되었고, 수량은 13.5~34.4% 정도 증수되었다.

• 농촌의학ㆍ지역보건
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• 제1권1호
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• pp.10-21
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• 1976

The traditional application of night soil to vegetable gardens and rice paddies results in a most wide spread condition of parasitism, with a variety of helminths found in Korea. In addition to the above fact, the peculiar habit of the consumption of raw vegetables, fish, crustaceans and mammals provides a means of infestations of helminths. During the last sixty years numerous reports were found on the prevalence of helminths amongst the Korean population in different parts of the country, and it was generally recognized that ascariasis, hookworm disease, filariasis, clonorchiasis and paragonimiasis constitute the important helminthic disease in Korea. In practical measures of parasite control activities the main measures are summarized as mass-treatment, night-soil disposal and transmission control. Among the three, the mass-treatment has been commonly applied, however, no reduction of transmission has been obtained by treatment of a population. Therefore, the ultimate eradication of parasites will depend upon the application of comprehensive environmental sanitation measures. The basic environmental measures will be concerned with (a) the safe disposal of human excreta, (b) the provision of adequate and safe water supplies in such a way as to promote a higher standard of personal hygiene in the population, and (c) the prevention of food contamination by faecal material. Additional environmental measures will deal with the improvement of housing and housing hygiene and with general community development. Community development means social and cultural as well as economic development. The control measures on the parasitic endemic diseases, such as clonorchiasis and paragonimiasis are the good examples for community health development in Korea. The control of Clonorchis and Paragonimus infections are theoretically very simple, as the infection can only invade the human body by way of encysted metacercaria which are taken into the body when eating passive intermediate hosts(fishes, crabs and crayfishes). Although prophylactic measures in the case of the infections deal with above merely consist the fishes in cooking or submerging in hot water before eating them, it is exceedingly difficult to carry out such simple measures in face of century old traditions, to which the relatively primitive population clings with great tenacity. There is no one universally applicable method of control. The choice of methods must be dictated by the nature of the environment. the habit and custom of the people. the pattern of transmission and the resources of the country. There must exist a well organized public health infrastructure. Since a control programme is of necessity on a longterm basis and continuity in its implementation is essential. An investigation should be made on the prevalence of the diseases and its relationships to irrigation engineering, freshwater ecology, agricultural methods, hydro-electric schemes, and the development of communities in affected areas. In conclusion, however. the control of clonorchiasis and paragonimiasis in Korea is not an impossible task. A combination of efforts with major emphasis on health education and mass chemotherapy coupled with governmental aid in enforcing legislative public health measures could reduce the diseases. Health education in particular attempts following four things: (a) It supplies a person with enough general knowledge about a disease to make the preventive measures. (b) It makes a person feel sufficiently about the importance of his own health to make him alter his behavior and adopt these preventive measure. (c) It makes him concerned for the health others. (d) It tries to make him feel so strongly about the first three that be supports and even initiates preventive action by the community. Educational efforts should be directed primarily toward school children because it is during the early years that most persons become infected, and also because children are less entrenched in their food habits so that, the educational process should be involved at various levels in successive changes of knowledge, attitude, beha viour, habit and custom of their lives. The most parasitic endemic diseases are related to community diseases. In caring for a sick community. the first stage is to gather epidemiological data, the next is to make inferences from it-to make the community diagnosis. The third is to prescribe community treatment or community health action part of a community health action programme. The community health action is the sum of the steps decided upon to remedy the critical features revealed by the community diagnosis. Action takes various forms; health education is the most important.

• Weed & Turfgrass Science
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• 제2권1호
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• pp.38-46
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• 2013

토양 방선균 유래의 천연 제초활성 후보소재를 발굴하고, 이 후보소재의 온실 및 포장 실증 평가를 통해 보다 친환경적이고 효율적인 잡초 관리를 위한 잡초방제제로의 실용화 가능성을 검토하고자 본 연구를 수행하였다. 3,000여 종의 토양 방선균으로부터 강력하고 독특한 제초활성을 발현하는 후보 방선균 2종을 선발하였으며, 선발된 후보 방선균의 16S rDNA 서열을 분석한 결과 S. scopuliridis RB72와 가장 유사도가 높아 선발 균주를 S. scopuliridis KR-001이라 명명하였다. 후보 방선균의 최적 배양조건을 확립하였고, 온실 및 포장조건에서 주요 문제잡초와 난방제 잡초, 환경 위해 잡초 가시박 방제효과를 평가를 통해 친환경적인 천연물 제초제로서의 개발 가능성을 확인하였다. 한편, 후보 방선균 S. scopuliridis KR-001 배양액은 작물에 대한 선택성은 없었기 때문에 비선택성 경엽처리제로의 개발 가능성을 고려한 처리 농도 및 시기 등에 대한 진전단계 연구를 진행할 필요성이 제기되었다. 향후 배양액 수준에서 제형 연구를 통해 약효증진기술과 대량생산성 기술 개발을 통해 실용화 가능성을 검토하는 한편, 배양액 내의 살초성분에 대한 화학구조 구명을 통해 방선균 유래의 천연 제초제를 개발 할 수 있는 선도물질 발굴을 위한 추가 연구가 필요한 것으로 판단하였다.

• 한국학교ㆍ지역보건교육학회지
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• 제1권2호
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• pp.49-71
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• 2000

The purpose of this study was to serve as a basis for school health care of better quality, by making a comparative analysis of the health care satisfaction and attitude of elementary school students in consideration of their general characteristics and the presence or absence of nurse teacher. The subjects in this study were 919 selected six graders in 16 elementary schools in the city of Tongduchun, Koyang and Euijungbu, Yangju-kun and Yeunchun-kun. A survey was conducted with questionnaire designed for measurement of health care satisfaction and attitude. As a result of analyzing the data collected from June 1 through 15, 2000, the conclusions were as follows. 1) As for the general characteristics of the students investigated, the subjects included 513 boys(55.8%) and 406 girls(44.2%). The schools where 390(42.4%) students attended were located in municipal area, and the schools where 529(57.6%) students attended were located in kun area. 608(66.2%) students had a nurse teacher at their schools, while 311(33.8%) students had no nurse teacher. 498(54.2%) had an experience to use the health room this year, but 421(45.8%) had no such an experience. Their mean school life satisfaction was scored $3.42{\pm}.71$, above the average. And their health condition was rated $3.81{\pm}.87$, which implied they tended to be in good health. 2) The mean satisfaction at the health room operation was scored $3.33{\pm}.71$, above the medium level. What they were most satisfied with($4.02{\pm}1.08$) was, among the health room facilities, that there were beds. But they expressed the least satisfaction($2.83{\pm}1.17$) at the location of health room. The presence or absence of nurse teacher made a significant difference to their satisfactionat health room operation, because the students in schools with nurse teacher showed greater satisfaction($3.42{\pm}.72$) than the others in schools with no nurse teacher did($3.15{\pm}.66$). 3) Concerning their attitude to use the health room in case of disease or accident occurrence, a lot of students in schools with a nurse teacher, who had ever suffered from indigestion, headache or traumatic injury, used the health room. In schools with no nurse teacher, there was a tendency to talk to their class teachers(p<.001). The recognition of the necessity for health counseling was generally on a medium level. The counselor whom they wanted to discuss health problem with was family or friend in the largest cases. Few students discussed with class teachers in case there was a nurse teacher in school. Instead, some of them discussed with friend, family or nurse teacher, and there was a significant difference between them(p<.001). 4) The mean satisfaction at health, sanitation and environmental management was rated $3.20{\pm}.90$, above the average. The classroom lighting gave them the best satisfaction with $3.67{\pm}1.07$, but the satisfaction at toilet cleanness and disinfection was not good with $2.83{\pm}1.19$. By the presence or absence of nurse teacher, those who had a nurse teacher expressed better satisfaction at water supply facilities including hot water than the others who had no nurse teacher did(p<.001). But no significant difference was observed in the other items. 5) The health education satisfaction was rated $3.19{\pm}.99$, which was on a medium level. By item, the mean satisfaction level was $3.36{\pm}1.19$ at nurse teacher's explanation about treatment, $3.13{\pm}1.15$ at the frequency of health education, and $3.08{\pm}1.16$ at the explanation on the cause of disease. By the presence or absence of nurse teacher, the students with nurse teacher showed significantly better satisfaction at every factor0(p<.001). 6) Regarding health education attitude, their recognition of the need for school health education was scored $3.89{\pm}.96$. Those who had a nurse teacher felt it more necessary($3.96{\pm}.92$), yet the others who had no nurse teacher felt its necessity a little less($3.74{\pm}1.01$). The most preferred thing for them to learn in health education was first aid, followed by sex education, obesity prevention, safety accident prevention in school and outdoors, smoking-related health, good use of leisure time, and environmental pollution cause in the order named. According to the presence or absence of nurse teacher, there was a significant difference in sex education(p<.01), but no significant disparities were found in the other factors. The most preferred person who would offer health education was a lecturer from the outside(45.8%) and nurse teacher(45.4%). Their preference for class teacher as a person in charge of health education was just 8.8%. But the presence or absence of nurse teacher didn't produce any differences to their preference for a person in charge of health education.

• 한국조경학회지
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• 제41권6호
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• pp.72-83
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• 2013

본 연구는 옛 문헌과 그림에 담긴 탁족(濯足)의 문화현상과 그 기저에 담긴 배경 및 의미를 고찰함으로써 탁족 문화를 계승하기 위한 조경적 대안을 제안해 보고자 한 것으로 주요 결과는 다음과 같다. 자연 질서에 순응하고 세속으로 부터 초연(超然)한 삶을 비유한 '탁영탁족(濯纓濯足)'의 고사는 '은일(隱逸)'을 통해 유유자적하는 탁족지유(濯足之遊)로 승화되었다. 선비가 유연(柔軟)한 계류에 발을 담그는 것은 자연과 물아일체(物我一體) 함으로써 도(道)와 상합(相合)되고자 하는 것으로 이러한 모습은 자유로운 정신세계인 '유(遊)'의 경지이자 본질과 상통한다. 탁족의 문화현상은 고려 말 이후 조선시대 전래경관에서도 잘 드러나는데 팔경시(八景詩)에 나타난 탁족은 고답적(高踏的)인 것이라기보다는 일상에 깃든 생활경이기도 하였다. 탁족도에 묘사된 맑은 물이 흐르는 계류[淸溪]와 바위, 그리고 소나무 등 교목이 우점(優占)하는 산수는 뜻 높은 선비의 은일공간으로 기호화되고, 그 정신세계는 더욱 부상되었다. 중국의 탁족도에서는 '청계(淸溪)'와 '창랑(滄浪)'을 강조함으로써 더러움에 대비되는 청류(淸流)의 이미지와 상고성(尙古性)이 강하게 부각되고 있는 반면, 조선시대 그것은 상대적으로 은일과 탁족지유라는 내면적 즐거움이 더욱 부각되고 있다. 탁족도에 나타난 자연관은 자연의 섭리를 그림 속에 그려진 선비의 상황 및 태도로 비유하여, 산수에 대한 사랑과 그 속에서 여유를 즐기는 가운데 무위자연(無爲自然)의 도를 깨닫게 하는 도가적(道家的) 관점의 표현이 잘 드러난 것으로 이는 중국은 물론 조선의 시대정신과 미의식의 한 단초를 보여준다. 요컨대 양국의 '탁족지유'는 인격수양이나 처신, 또는 은둔과 고답(高踏)의 상징으로 해석되면서 한편으로는 현실세계에서 납량의 수단으로 수용되어 왔다. 탁족 행위에는 선비들의 이상과 상고주의(尙古主義) 정신이 깃들어 있을 뿐 아니라, 일반 서민의 더위를 이기는 지혜가 담겨 있음은 깊이 되새겨 봐야 한다. 이러한 관점에서 환경적 지원성에 입각한 수공간과 탁족바위 그리고 물의 활용은 휴양 레크레이션 공간에서 새롭게 조명되어야 할 대상이며, 탁족 행위에 깃든 정신이야말로 고전적 치유(治癒)의 정신문화였음을 일깨워 준다.

• Korean Chemical Engineering Research
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• 제50권3호
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• pp.492-498
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• 2012

본 연구에서는 고온고압 건식탈황장치를 이용하여 고체순환량과 탈황반응기 내의 공극률에 대한 수력학적특성을 파악하고, 아연계 탈황제의 고온고압 조건에서 탈황반응온도에 대한 반응특성 및 연속운전을 통한 탈황 효율을 분석하였다. 실험에 사용된 고온고압건식탈황장치는 고속유동층 형태의 탈황반응기(내경: 0.015 m, 높이: 6.2 m), 기포유동층 형태의 재생반응기(내경: 0.053 m, 높이: 1.6 m), 가스의 역흐름을 방지하는 loop-seal, 두 반응기 후단에 압력컨트롤밸브로 구성되어있다. 수력학 특성으로는 고체순환밸브 개구비, 탈황반응기 가스 유속, 탈황반응기 온도 변화에 따른 고체순환량과 각 조건에서의 고속유동층 형태의 탈황반응기 높이에 따른 공극률 분포를 알아보았다. 고체순환량은 동일한 유속조건, 동일한 고체순환밸브 개구비에서 탈황반응기 온도가 상온일 때보다 $300^{\circ}C$와 $550^{\circ}C$일 때 감소하였으며 $300^{\circ}C$와 $550^{\circ}C$ 조건에서는 큰 차이가 없었다. 탈황반응기내의 공극률은 고체순환밸브 개구비가 10~20%로 고체순환량이 적은 경우 고속유동층 형태의 공극률 분포를 보이고, 30~40%로 고체순환량이 많아지는 경우 탈황반응기 하부에서 turbulent 형태의 공극률의 분포를 나타냈다. 아연계 탈황제의 탈황반응온도에 따른 반응특성은 시스템 압력 20 atm, 연속 반응 조건에서 탈황 온도를 변화시키면서 살펴보았다. 일정한 고체순환 조건에서 탈황온도 $450^{\circ}C$ 이하에서 탈황 효율 저하가 시작되는 것을 확인하였으며, 높은 탈황 효율을 유지시키기 위하여 10시간 연속운전에서는 탈황 반응 온도를 $500^{\circ}C$로 설정하여 실험하였다. 실험 결과, 10시간 연속운전을 통해, 유입 $H_2S$ 농도 5,000 ppmv 조건에서 탈황 반응기 후단 $H_2S$ 농도는 UV분석기(Radas2)와 검지관(GASTEC)의 검출한계인 1 ppmv 이하를 유지하여 $H_2S$ 제거 효율 99.99% 이상을 달성하였다.

• 대한건축학회논문집:구조계
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• 제33권12호
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• pp.81-90
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• 2017

This study was conducted to investigate the thermal environment status of nursery rooms in workplace daycare centers in Jeju and propose measures to improve their indoor physical thermal environment. For this purpose, measurements were performed in the winter indoor physical environment of 51 nursery rooms in 11 workplace daycare centers and a psychological evaluation survey on the thermal environment of nursery rooms was conducted for 70 nursery teachers. The investigation was carried out over 11 days in January 2017. The results are as follow. The average indoor temperature of the nursery rooms was $21.3^{\circ}C$($18.7-23.8^{\circ}C$) and the indoor temperatures of 47 nursery rooms (92.9%) were higher than the environmental hygiene management standard for domestic school facilities ($18-20^{\circ}C$). The average relative humidity was 33.9% (16.4-56.0%), and 37 nursery rooms (86.3%) showed a lower average relative humidity than the standard (40-70%). The average absolute humidity was $9.1g/m^3$ ($4.7-13.6g/m^3$), which was lower than the standard for preventing influenza ($10g/m^3$). When the indoor temperature and humidity of the nursery rooms were compared with international standards, it was found that 85% or more of the 51 nursery rooms maintained appropriate indoor temperatures, but 40-50% of the nursery rooms maintained a low humidity condition. Therefore, they need to pay attention to maintaining the appropriate humidity of the nursery room to keep the children healthy. The average indoor temperature of the nursery rooms showed a weak negative correlation with the average relative humidity. The indoor temperature had a significant effect on the relative humidity: a higher indoor temperature resulted in lower relative humidity. Regarding the fluctuations in the average indoor temperature of the nursery rooms during the day, in daycare centers that used floor heating, the indoor temperature gradually increased form the morning to the afternoon and tended to decrease during lunch time and the morning and afternoon snack times, due to ventilation. The daycare centers that used both floor heating and ceiling-type air conditioners showed a higher indoor temperature and greater fluctuations in temperature compared to the daycare centers that used floor heating only. In the survey results, the average value of the whole body thermal sensation was 3.0 (neutral): 32 respondents (62.7%) answered, "Neutral", Which was the largest number, followed by 21 respondents (30%) who answered, "Slightly hot" and 17 respondents (24.2%) who answered, "Slightly cold." Twenty-nine respondents answered, "Slightly dry," which was the largest number, followed by 28 respondents (54.9%) who answered, "Neutral" and 10 respondents (19.6%) who answered, "Dry." The total number of respondents who answered, "Slightly dry" or "Dry" was large at 39 (56.4%), which suggests the need for indoor environment management to prevent a low-humidity environment. To summarize the above results about the thermal environment of nursery rooms, as the indoor temperature increased, the relative humidity decreased. This suggests the effect of room temperature on the indoor relative humidity; however, frequent ventilations also greatly decrease the relative humidity. Therefore, the ventilation method and the usage of air conditioning systems need to be re-examined.