• 폴리머
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• 제36권3호
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• pp.380-392
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• 2012

치환도(DS) 그리고 몰치환도(MS)가 각각 2.47~2.52 그리고 4.9~7.8 범위에 있는 4 종류의 N,O-히드록시프로필 키토산들(HPCTOs)을 합성함과 동시에 이들의 분자특성과 열방성 및 유방성 특성을 검토하였다. MS는 DS에 비해 대단히 큰 경향을 나타냈다. 이러한 사실은 반응이 진행됨에 따라 프로필렌 옥사이드는 주사슬보다 곁사슬들에 우선적으로 부가됨을 시사한다. 모든 유도체들은 열방성 콜레스테릭 상들을 형성하였다. 유리 그리고 액정 상에서 액체 상으로의 전이 온도들은 MS가 증가함에 따라 낮아졌다. 열방성 콜레스테릭 상들의 광학피치들(${\lambda}_m$'s)은 온도가 상승함에 따라 증가하였다. 그러나 유도체들이 동일한 온도에서 나타내는 ${\lambda}_m$들은 MS가 증가함에 따라 증가하였다. 고분자의 농도가 30 wt% 이상인 HPCTO들의 물, 메탄올, 에탄올, 아세트산 그리고 포름산 용액들도 고분자의 농도가 증가함에 따라 ${\lambda}_m$이 지수 함수적으로 감소하는 콜레스테릭 상들을 형성하였다. 그러나 HPCTO 용액들의 ${\lambda}_m$의 농도의존성은 용매의 성질과 MS에 민감하게 의존하였다. HPCTO들의 열방성과 유방성 액정 상의 특성들은 히드록시프로필 셀룰로오스들에 대해 보고된 결과들에 비해 현저히 달랐다. 이러한 결과들은 C-2 위치에 존재하는 2차 아미노기가 콜레스테릭 상의 형성능, 안정성 그리고 ${\lambda}_m$의 온도와 농도의존성에 중요한 역할을 함을 시사한다.

• 물과 미래
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• 제29권6호
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• pp.179-188
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• 1996

수자원의 주공급원인 강수는 현상의 발생여부에 따라 건조일과 습윤일이 교대로 반복되는 과정으로 구성되어 있으며, 특히, 일강수계열의 습윤일에 발생되는 강수량의 크기는 매우 다양한 형태를 지니고 있어 이 과정을 모형화 하는데는 복잡한 확률과정이 수반된다. 본 연구에서는 일강수계열의 발생과정을 건조일, 습윤일로 구분하고 습윤일의 강수량을 상태별로 분류하여 각 상태별 천이확률을 계산함으로써 이를 장래에 발생 가능한 강수사상의 모의발생에 이용하였다. 본 모형은 수문사상의 발생과 비발생만을 구분하던 2-state Markov 연쇄모형에 강수의 발생시 강수량의 크기에 따라 상태를 여러 개로 구분하여 강수량을 추정할 수 있도록 수정한 것으로 간헐 수문사상인 일강수계열의 구성성분인 건조일과 습윤일, 건조, 습윤 지속기간 및 습윤일의 강수량을 Markov 연쇄에 의해 동시에 발생있도록 한 것이며 다른 모형에 비해 사용이 비교적 용이하다. 본 연구에서 제안한 multi-state Markov 연쇄모형의 적용 가능성을 검토하기 위하여 비교적 장기간의 자료를 보유하고 있는 관측소의 강수자료를 이용하였으며 그 결과를 강수량, 건조, 습윤일수 및 건조, 습윤계속기간의 분포를 실제자료와 비교하여 모형의 적합도를 평가하였다. 이를 토대로 홍수 및 한발기간의 추정과 모의발생에 의한 자료 확장으로 중장기 수자원 계획 및 운영에 효율적으로 이용될 수 있을 것으로 판단된다.

• 기본간호학회지
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• 제3권1호
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• pp.108-127
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• 1996

The purpose of this research was to determine whether or not a education program of low back pain would have benificial effect on nurses. Nonequivalent control group pre-post test research was designed. Subjects for this study were 50 selected from nurses who work at a general hospital in Taegu. Of them, twenty seven were assigned to experimental group, twenty-three to control group. The data were collected during the period from June 27 to August 31, 1994. The instruments used in this study were Visual Analog Scale for low back pain, Sit-and-reach test for trunk flexibility, and 1 min sit up test for abdominal muscle endurance. Data related to general chracteristics and factors of low back pain were collected with questionnaire developed by this reseacher. The data were analyzed by $X^2-test$, t-test and paired t-test, using the SAS package program. The results of this study are summerized as follows : 1. The numbers of the experimental group with low back pain were not a statistically significant difference from pre to posttesting($X^2=0.77$, p=.379), and the numbers of the control group with low back pain were also not a statistically significant difference from pre to posttesting($X^2=0.09$, p=.767). 2. The severity of low back pain of the experimental group was not a statistically significant difference from pre to posttesting(t=-0.55, p=.5857), and the severity of low back pain of the control group was also not a statistically significant difference from pre to posttesting(t=-0.70, p=.3101). 3. The trunk flexibility of the experimental group was not a statistically significant difference from pre to posttesting(t= 1.08, p=.2835), and the control group's trunk flexibility was also not a statistically significant difference from pre to posttesting(t=0.85, p=.4026). 4. The abdominal muscle endurance of the experimental group was a statistically significant difference from pre to posttesting(t=-2.42, p=.0190), but the control group's abdominal muscle endurance was not a statistically significant difference from pre to posttesting(t=-0.06, p=.9556) This study suggest that replication of study with more sample and more rigid treatment should be needed. And furthermore, the longitudinal research is needed to determine the effectiveness of education program.

• 대한지리학회지
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• 제29권3호
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• pp.340-359
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• 1994

This study intends to describe the characteristics of the transformation of the rural society by tracing the changing social and economic processes of traditional clan villiage (Yeolmi-ri, Silchon-myeon, Kwangju-gun, Kyunggi-province) in the suburbs of Seoul Metropolitan Area. Rural society has experienced serious change of the social structure by the ever expanding urbanization and industrialization since 1960's. The suburbs of Seoul Metropolitan Area is the representative case area of such transformation. This study analyzed various chracteristics of population structure of a villiage, the processes of residential movement and the occupational shift of each household of the villiage in terms of household's life-history collected by interviewing with each household. And the whole households of a villiage is divided by two groups of the native clan group and the non-dan in-migrant group. The results of this study are summarized as follows. 1) This villiage is located within a lineal distance of 40km and a time distance of about 30 to 40 minutes, adjoined dy the Joongbu(중부) national highway, the Kyungchoong (경충) industrial road, the local road between Yangpyuna(양평) and Gonjiam(곤지암) and having a advantageous iocational linkage to Seoul capital city. 2) It is a typical traditional dan villiae constituted of dan family Gu(구) one of whose ancestors had appointed to the prime minister of Chosun Dynasty, and until 1979, 56 out of 60 families of the villiage households were clan families. 3) Since 1979, as the villiage invaded by the out-movement of the small scale manufacturing industries from Seoul capital city, labours moved in this vallige from outside and increased villiage size up to 203 households in 1993, consequently the constitutional proportion between the native clan group and the non-clan in-migrant group was reversed up to 28% vs 72% deepening the sociological heterogeneity. 4) Because of the small scale of industries in this villiage and the vicinity with the city of Seoul, the population turnover of this villiage is very high. The turnover frequency is firstly high within same administrative district of gun(군) level and secondly high between this villiage and the city of Seoul. Thus short-distance movement is identified. 5) There is a close correlation between the residential movement and the occupational shift. The most numbers of non-farm native group have the experiences of migration while the members of native farming group don't shift both the job and the place of residence. The inmigrant group had several migration experiences but few occupational shifts. Thus occupatioanl shift is high for the native group while residential shift is high for the in-migrant group. It is concluded that the change proceeded in Metropolitan suburbs was not directed to form the traditional rural village as 'gesund Gebiet' with respect to the ballance among the economic, cultural and environmental adequency.

• 한국균학회지
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• 제16권2호
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• pp.79-86
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• 1988

잔나비걸상버섯과 영지(靈芝)버섯간(間)에 원형질체융합(原形質體融合)을 실시하여 융합(融合)된 균주(菌株)를 선발하있으며, 융합(融合)된 균주(菌株)를 배양(培養)하여 자실체(子實體)의 형성(形成)하였는 바 그 결과(結果)를 요약하면 다음과 같다. 1. 잔나비걸상버섯 영지(靈芝)버섯간(間)의 종간원형질체융합률(種間原形質體融合率)은 $0.77{\sim}l.38%$였다. 2. 융합(融合)된 균총(菌叢)은 MMM배지상(培地上)에서 균총(菌叢)의 형태적(形態的) 차이를 보이거나 균총(菌叢)의 중앙부위(中央部位)에 잃은 황양색(黃楊色)을 띄고 있었다. 3. 융합주(融合株)는 두 모균주(母菌株)의 장점을 지녔고 대체로 모균주(母菌株)보다 빠른 성장(成長)을 보였으며, 균주(菌株)에 따라서는 GCM 배지상(培地上)에서 segregation이 일어난다. 4. 융합주(融合株)의 균사체(菌絲體)에는 clamp connection이 없으나 segregation이 일어난 균사(菌絲)에서는 있는 것과 없는 균사(菌綿)가 혼재(混在)해 있있다. 5. 균사체(菌絲體)를 마쇄하여 전기영동(電氣泳動)에 의한 esterase isozyme pattern을 확인해 본 결과 모균주(母菌株)와는 전혀 다른 band를 나타내 었다. 6. 선발(選拔)한 30균주중(菌株中) 4균주(菌株)에서 자실체(子實體)가 형성(形成)되었으며 그 형태(形態)는 모균주(母菌株)의 자실체(子實體)와 차이를 보였다.

• 한국수산과학회지
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• 제19권1호
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• pp.20-26
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• 1986

Very little information is available in the literature on storage of fish sauce. Therefore, microbiological and chemical chracteristics during storage and quality of fish sauce were investigated and discussed to present data about the optimum storage condition. The chopped sardine meat was mixed with equal amount of water and $9\%$(w/w) of $75\%$ vital wheat gluten and then hydrolyzed by addition of commercial proteolytic enzymes such as bromelain, papaya protease, ficin and a enzyme mixture (Pacific Chem. Co.) for 4 hours at $52.5^{\circ}C$. The reaction mixture was heated for 30 min at $100^{\circ}C$ for enzyme inactivation, pasteurization and color development and then centrifuged for 20 min at 4,000 rpm. Table salt and benzoic acid were added for bacteriostatic effect and stored for 80 days at $15{\pm}1^{\circ}C$ and $30{\pm}1^{\circ}C$. The results were summarized as follows: 1. The amount of amino-nitrogen and pH of fish sauce were almost unchanged during storage. 2. Mininum concentration of salt for bacteriostatic activity was $9\%$(w/w) regardless of addition of benzoic acid. 3. the yields of amino-nitrogen were $63.1\%$ for the hydrolysate prepared without enzyme, $79.7\%$ for that with bromelain, $69.9\%$ with ficin, $74.3\%$ with papaya pretense, and $78.1\%$ with enzyme mixture, respectively. 4. The contents of amino-nitrogen were $4510.0mg\%$ on the dry basis for the product prepared by autolysis, $5483.2mg\%$ for that prepared with bromelain, $5305.7mg\%$ with ficin, $4994.1mg\%$ with papaya protease and $5582.3mg\%$ with the enzyme mixture, respectively. 5. The contents of crude protein were $51.35\%$ on the dry basis for the product prepared by autolysis and 55 to $59\%$ for prepared with commercial enzymes. 6. The hydrolysate prepared with the enzyme mixture revealed a little stronger meaty taste than any other products. 7. The level of crude protein in residues was still high ($69.5{\sim}77.2\%$ on the dry basis) and might be originated from the added vital wheat gluten.

• 지역연구
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• 제13권2호
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• pp.55-74
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• 1997

This paper investigates the spatial characteristics of networks, which arise as a firm's strategy to enhance its competitiveness to cope with the changing economic environments characterized by technological changes and increasing competitiveness. The theoretical framework in this study proposes that networks emerge as a firm's strategies to promote its competitiveness through the vertical/horizontal disintegration of the production system. Futhermore, regional industries of networks. The study examines the types of cooperation and the spatial boundary of the computer industry networks in Korea. Questionnaire survey was conducted on 1, 128 computer companies which had more than 10 employees, with 126 questionnaires being used for analysis. In addition, newpaper articles were used to supplement the foregoing work on network characteristics. The review of these articles covers the period from Jan. 1994 to June 1996. Major findings of this study are as follows: The spatial range of cooperative networks varies according to the specific characters of cooperation(R & D, production, and seles). Intralocal networks are being developed in Kangnam and Youido area, the computer industry agglomeration clusres of Seoul. There are the regional differnces in the agents and contents of cooperation. In intra-national R & D and production networks, regional differnces in agglomeratins and non-agglomerations are not detercted. Most networks of this type are found between large firms and small firms. In contrast, foregn R & D and production networks, which are operated mostly by large firms, are found in Kangnam, Youido, and CBD. Intra-national and foreign productino networks are also focused in Kangnam, Youido, and CBD. Small firms are playing an active role in making this type of cooperation possible. In the perspective of localization-globalization, Korean computer industry can be analyzed in two respects: industrial and regional. The localization of small firms and the localization-globalization of large firms' networks are being developed in industrial contexts, while the localization-globalization of agglomerations and the localization of non-agglomerations networks are being developed in regional contexts. As networks for the localization-globalization of industry are growing in agglomerations, interfirm networks could be related to trends in the formation or intensification of industrial agglomerations. industrial agglomeration areas function as a facilitator of localization through subcontracts, intraregional network and interregional network. They also facilitate globalization via foregn networks. In non-agglomeratin areas, localization networks, which are connected with agglomeration areas via subcontracting, interregional R & D. or production cooperation.

• 한국초지조사료학회지
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• 제16권2호
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• pp.147-154
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• 1996

Rye(Secale cereale L.) shows lower dry matter yield and nutrient content when it was harvested before wintering. This study was conducted to investigate how effect forage rape(Brassicu napus Subsp oleifera), which carries early maturity and can be harvested before wintering, on the increase of the forage yield and nutrient content when rye was sown mixed with the rape. Optimum sowing rate of the rye/rape mixture was also pursued in this study. The five treatment of rye single, rape single, ryel20+rape 1Okg/ha, rye84+rape 7kg/ha and rye60+rape 5kg/ha were sown on 2 September 1989. Rape single plot was cut one time(l9 November 1989) and the other plots were cuted two times(19 November 1989 and 20 May 1990). In botanical composition of the mixtures, rape recorded dominant ratio with 64~69% at the autumn cut. The rye84+rape 7kg/ha mixture plot marked the highest dry matter yield with 4.46t/ha among all the experimental plot at the autumn cut(P<0.05). In year total yield of dry matter(t/ha), rye single, rape single, rye120+rape IOkg/ha, rye84+rape 7kg/ha and rye60+rape 5kg/ha marked 13.6, 4.1, 12.7, 12.9 and 11.8, respectively. In crude protein content, the rye single plot was 17.2% at the autumn cut on the other hand the mixture plots showed increasing tendency with 18.0~19.9%. In crude fiber content, the mixture plots were remarkably lower than rye single plot. In year total yield of crude protein, rye84+rape 7kg/ha mixture plot showed the highest yield with 1.6lt/ha among all the experimental plots. Ratio of crude protein yield to crude fiber yield, rye84+rape 7kg/ha tended to be higher than the other mixture plots. It is confirmed that the rye/rape mixture can produce more forage than the rye single cropping when they are harvested in late autumn, besides the mixture forage contains higher crude protein than that rye single forage. It can be said that the rydrape mixture is more useful than the rye single cropping, and optimum sowing rate of the mixture is 84kg/ha of rye+7kg/ha of rape.

• 한국미생물·생명공학회지
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• 제20권4호
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• pp.377-383
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• 1992

Bacillus thuringiensis 7균주를 한국의 토양에서 분리하여 특성을 연구했다. 상기의 7균주를 HL-8, 10, 12, 13, 14, 15와 16으로 명명했으며, 이들 균주들은 세포내의 다양한 형태의 parasproal endotoxin crystal과 내생포자를 형성한 것을 위상차현미경으로 관찰했다. 분리균주들의 생화학적인 특성은 이미 알려진 균주들과 유사했으나, 특이한 차이점을 가지고 있었다. 각 분리균이 가지고 있는 플라스미드를 분리하여 분자량과 수를 조사한 결, HL-8 과 HL-10은 6종류의 플라스미드를 가지고 있었으며, 분자량의 범위는 3.01-15.1Md 이었고, HL-12균주는 4종규의 플라스미드를 가지고 있었으며, 분잘량의 범위는 5.4-21.9Md이었고, HL-13균주도 4종류의 플라스미드를 가지고 있었으나 분자량은 차이가 없었다. HL-15균주도 3종류의 플라스미드를 가지고 있었으며, 분자량의 범위는 2.4~13.5Md이었고, HL-15균주도 3종류의 플라스미드를 가지고 있었으며, 분자량의 범위는 3.4~11.4Md이었고, HL-16도 3종류의 플라스미드를 가지고 있었으며, 분자량의 범위는 2.4~20.1Md이었다. 상기 분리균는 공히 ampicillin, bacitracin, cephalothin, methicillin과 penicillin G에 저항성을 나타냈다. HL-8과 15는 48시간내에 Culex pipiens 모기 3령유충에 100%의 살충성을 나타냈고, 다른 균주는 이보다 낮았다. 특히 HL-13은 살충성이 없었다.

• 한국식품과학회지
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• 제33권3호
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• pp.319-326
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• 2001

국산 포도주의 개발을 목적으로 당도 $12^{\circ}Brix$, 산도 0.7%인 1999년도 충북 영동산 Campbell Early 품종의 포도에 여러 종류의 당을 첨가하여 포도주의 발효 특성을 조사하였다. 설탕, xylitol, 포도당, 물엿, 고과당, 이소말토올리고당 등 6가지 각기 다른 당 또는 당 알코올을 최종 당 농도 $21^{\circ}Brix$가 되도록 포도에 첨가하였고 활성 건조 효모를 0.02%(w/v) 첨가하여 발효시켰다. 전발효는 $20^{\circ}C$에서 8일간, 후발효는 $13^{\circ}C$에서 70일간 행하였다. 포도주 발효속도는 포도당을 첨가한 시험구가 가장 빨라 발효 6일만에 12%(v/v)의 알코올을 생성하였고 이 때 당도는 $5.5^{\circ}Brix$를 나타내었다. 설탕과 고과당을 첨가한 포도주도 포도당과 비슷한 경향을 나타내었으나 최종 알코올 함량은 각각 10.3%(v/v)와 11.2%(v/v)로 포도당 첨가구보다는 약간 낮았다. 한편 물엿, xylitol, 이소말토올리고당을 첨가한 포도주는 포도당을 첨가한 시험구와 초기 발효 속도는 비슷하였으나 최종 포도주의 알코올 농도가 평균 7%(v/v) 정도로 상대적으로 낮았다. pH는 발효 기간 중에 큰 변화가 없었고 첨가한 당에 따라서도 큰 차이가 없었으며 총산은 전체적으로 약 0.7%에서 0.3% 이하로 감소하였다. 색도는 발효가 진행됨에 따라 시험구 모두 점차 붉은 색이 짙어졌는데 그 중 설탕, xylitol, 이소말토올리고당의 첨가구가 붉은 색을 진하게 나타내었다. 80일간의 숙성을 거친 포도주의 관능 검사 결과 단맛과 청량감이 있는 xylitol 첨가구가 평균 8.96으로 가장 높은 선호도를 나타냈으며 당 분석 결과 포도주 내에 xylitol이 발효되지 않고 그대로 남아있음을 알 수 있었다.