• 한국환경생태학회지
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• 제29권6호
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• pp.873-883
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• 2015

2012년 8월부터 2013년 4월까지 양재천의 어류상과 복원 후 특성을 조사하였다. 조사기간 동안 채집된 어류는 총 5과 18종 1,503개체가 확인되었다. 하천복원 이후 양재천에 서식하는 담수어류 분포 조사결과 피라미(Zacco platypus)와 버들치(Rhynchocypris oxycephalus) 개체군이 높게 나타났다. 양재천에 서식하는 피라미 개체군의 전장 빈도 분포 결과 총 4단계의 연령대가 추정되었으며, 27~63mm (Age $0^+$)가 51.3%로 가장 높게 나타났다. 피라미의 전장-체중 상관도의 회귀계수 b값은 3.27, 비만도지수 slope는 양의 값으로 안정적인 생육상태를 유지하고 있었다. 내성도와 섭식도 길드 분석 결과 하류로 내려갈수록 민감종과 충식종은 개체수 풍부성이 감소하고, 내성종과 잡식종은 증가하였다. 군집지수와 IBI지수를 활용한 주성분 분석 결과 조사시기에 따라 구분되었으며, 1차와 2차조사시 특정 단일종 개체군의 영향이 높고, 3차조사시 다양한 어류의 개체수가 균등하게 서식하는 것으로 분석되었다.

• Elastomers and Composites
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• 제21권1호
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• pp.13-19
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• 1986

최근(最近)에 와서는 황(黃)에 의(依)한 고무의 가황반응(加黃反應)이 발열반응(發熱反應)이라는데 주안점(主眼點)을 두어 근래(近來) 고분자화학(高分子化學) 분야(分野)에서 그 활용도(活用度)가 높은 열분석기(熱分析機) (특(特)히 DSC, DTA)가 가황발열현상연구(加黃發熱現象硏究)에 많이 이용(利用)되고 있다. 그러나 고무의 가황반응(加黃反應)을 속도론적(速度論的)으로 연구하여 이론적(理論的) 기초(基礎)를 확립(確立)하여 두는 것이 필요(必要)하다는 것은 여러 학자(學者)들이 전(前)부터 느껴왔으나 고무탄성체(彈性體)는 한번 가황(加黃)되면 일반적(一般的)인 용매(溶媒)에 의(依)한 용해(溶解)가 어렵기 때문에 반응물(反應物)(황, 가황촉진제(黃, 加黃促進劑))이나 생성물(生成物)의 농도측정(濃度測定)에 의(依)한 가황반응(加黃反應)의 속도론적(速度論的) 연구(硏究)가 어려웠다. 그래서 본(本) 연구(硏究)에서는 DSC(Differential Scanning Calorimetry)를 이용(利用)하여 얻은 천연(天然)고무의 가황발열(加黃發熱) thermogram을 Borchardt-Daniel이 제안한 방법으로 분석(分析)하여 kinetic data(즉, rate constant k, frequency factor ko, Activation Energy Ea)를 얻었다. 또한 이 kinetic data가 가황촉진제의 종류(種類)에 따라 어떻게 달라지는지, 실제공정(實際工程)에서 적정가황시간(適正加黃時間), 온도(溫度), 가황촉진제(加黃促進劑)의 종류(種類), 배합량(配合量) 결정(決定)에 활용(活用)할 수 있는 방안(方案)에 대(對)해서도 관심을 두고 검토(檢討)하였다. 한편 DSC에 의(依)한 방법(方法)의 신뢰도를 검토하기 위하여 DSC용(用)으로 쓰여진 것과 동일(同一)한 시료를 사용하여 Oscillating Disk Rheometer에 의한 Cure Curve를 얻고 이 Cure Curve를 분석(分析)하여 얻은 kinetic data를 앞서 구한 data와 비교검토(比較檢討)하였다.

• 대한지역사회영양학회지
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• 제7권4호
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• pp.527-538
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• 2002

Body antioxidant status is an important factor in the prevention of many chronic diseases caused by oxidative stress, especially in the elderly and is affected by health-related habits, such as smoking, drinking and regular physical activity. The aim of this study was to investigate the relationship between these health-related habits and plasma antioxidant status in the elderly. Plasma antioxidant status was examined by determining plasma levels of antioxidant vitamins (vitamin C, A, E, $\beta$ -carotene), total antioxidant status (TAS) and thiobarbituric acid-reactive substance (TBARS) . The subjects included 225 elderly persons aged over 60 yews (63 males, 162 females) living in the Ulsan area. They were interviewed to collect data on their general characteristics and health behaviors such as smoking, exercise and alcohol consumption by means of questionnaires. Their dietary intakes were obtained by means of semi-quantitative food frequency questionnaires (FFQ) The study population was divided into two or three groups according to their smoking, drinking, and exercise status. The ratio of smoker, drinker and exerciser was 16.7%, 31.0% and 44.2% respectively. The dietary antioxidant vitamin intakes were not significantly different among groups of smoking and drinking status, but tended to be higher in non-smokers and non-drinkers than in smokers and drinkers. Plasma vitamin C and $\beta$ -carotene levels were significantly higher in non-smokers, but Plasma vitamin A and TBARS levels were significantly lower in non-smokers than in smokers. Plasma TAS was not significantly different among the smoking groups, but showed a tendency to decrease with an increase in the number of packyear. Plasma vitamin C and $\beta$ -carotene levels of the non-drinkers were higher than those of drinkers and past-drinkers, but plasma vitamin A, C, E, TAS and TBARS showed no difference among the groups of drinker. All vitamin intakes of the exercisers were slightly higher than those of the non-exercisers, but vitamin C intake was significantly higher in female exercisers than in non-exercisers. Plasma $\beta$ -carotene levels were significantly higher in male exercisers and plasma vitamin A, C, E, TAS and TBARS levels tended to be higher in exercisers than in non-exercisers. These results suggested that change to non-smoker, modulation of alcohol consumption and regular exercise could enhance antioxidant defences against reactive oxygen species and might increase the likelihood of a healthier life span.

• 한국환경보건학회지
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• 제41권4호
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• pp.231-240
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• 2015

Objectives: Blood mercury levels among adults living in certain areas of the Gyeongsang Provinces have been shown to be very high (Kunwee County $29.6{\mu}g/L$, Yeongcheon-city $26.7{\mu}g/L$). The purpose of this project was to determine mercury exposure levels in schoolchildren and factors related with their mercury levels in high mercury exposure areas identifyed by the 2007 Korea National Environmental Health Survey. Methods: From June to September 2010, 1,097 students from grades 3 to 6 at 19 elementary schools participated in this study, including 294 students from 10 elementary schools in Kunwee County, 529 students from Yeongcheon City, 122 students from two elementary schools in Pohang City, North Gyeongsang Province, and 152 students from two elementary schools in Ulsan Metropolitan City. Biological samples from schoolchildren, including whole blood, urine and hair, were collected to measure total mercury at the time of a health check up. Information about children was collected by questionnaire. Total mercury concentrations in blood were measured using the Direct Mercury Analyzer 80 with the gold-amalgam collection method. Results: The mean mercury levels were $2.70{\mu}g/L$ in 1,091 blood samples, $2.25{\mu}g/g-creat.$ in 820 urine samples and $1.03{\mu}g/g$ in 1,064 hair samples. Blood mercury levels in the schoolchildren was slightly higher than the result of $2.4{\mu}g/L$ from a 2006 survey of elementary school children on exposure and health effects of mercury by the National Institute of Environmental Research. However, 0.3% and 4.5% of participants exceeded the reference level of blood mercury by CHBMII ($15{\mu}g/L$) and the US EPA ($5.8{\mu}g/L$), respectively. The reference level of urine by CHBMII ($20{\mu}g/L$) was exceeded by 0.4% of participants. As factors, residence period in the study areas, residence type, father's education level and income all showed significant associations with mercury level in the biological samples. The number of dental amalgam sides showed an association with urine mercury. Fish intake preference and fish intake frequency were important factors in mercury levels. In particular, intake of shark meat and recent intake of shark meat were associated with higher mercury levels. In this regard, participation in the performance of an ancestral rite showed a relation with higher mercury levels. Conclusion: The intake of shark meat was very important factor to high mercury exposure level. It is recommended to monitor and manage students with high mercury exposures who exceeded CHBM II and EPA guidelines, and include blood mercury testing in the Children's Health check up for this province.

• Journal of Periodontal and Implant Science
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• 제34권3호
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• pp.607-622
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• 2004

Recently epidemiologic studies have indicated that the patients with periodontitis may have increased risk of ischemic cardiovascular events, and have suggested the important roles of blood cytokines and acute reactant proteins in the systemic infection and inflammatory response. Periodontitis and coronary heart disease (CHD) may share the common risk factors and the genetic mechanism associated with interleukin(IL)-1A, B and RA genotype may be involved in the production of IL-1. This study was aimed to investigate the relationship between angiographically defined CHD and periodontitis as chronic Gram-negative bacterial infection and to determine whether the IL-1 gene polymorphism is associated in both diseases. Patients under the age of 60 who had undergone diagnostic coronary angiography were enrolled in this study. Subjects were classified as positive CHD (+CHD, n=37) with coronary artery stenosis more than 50% in at least one of major epicardial arteries, and negative CHD (-CHD, n=30) without significant stenosis. After recording the number of missing teeth, periodontal disease severity was measured by means of plaque index (PI), gingival index (GI), bleeding on probing (BOP), probing depth (PD), clinical attachment level (CAL), and radiographic bone loss around all remaining teeth. Gingival crevicular fluid (GCF) was collected from the 4 deepest periodontal pockets and assessed for cytokine ($IL-1{\beta}$, IL-6, IL-1ra, tumor necrosis $factor-{\alpha}$, and prostaglandin $E_2$). Additionally, blood CHD markers, lipid profile, and blood cytokines were analyzed. IL-1 gene cluster genotyping was performed by polymerase chain reaction and enzyme restriction using genomic DNA from buccal swab, and allele 2 frequencies of IL-1A(+4845), IL-1B(+3954), IL-B(-511), and IL-1RA(intron 2) were compared between groups. Even though there was no significant difference in the periodontal parameters between 2 groups, GCF level of $PGE_2$ was significantly higher in the +CHD group(p<0.05). Correlation analysis showed the positive relationship among PD, CAL and coronary artery stenosis(%) and blood $PGE_2$. There was also significant positive relationship between the periodontal parameters (PI, PD, CAL) and the blood CHD markers (leukocyte count, C-reactive protein, and lactic dehyrogenase). IL-1 gene genotyping showed that IL-1A(+3954) allele 2 frequency was significantly higher in the +CHD group compared with the -CHD group (15% vs. 3.3%, OR 5.118,p=0.043). These results suggested that periodontal inflammation is related to systemic blood cytokine and CHD markers, and contributes to cardiovascular disease via systemic inflammatory reaction. IL-1 gene polymorphism might have an influence on periodontal and coronary heart diseases in Korean patients.

• 가족자원경영과 정책
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• 제16권4호
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• pp.131-152
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• 2012

The aims of this study were to analyze middle-aged households' financial preparation for retirement. Specifically, this study surveyed the relation between human capital investment for children and the middle-aged households' financial preparation for retirement and investigated factors influencing financial preparation for retirement. Data were obtained from the 3rd Korean Retirement and Income Study (KReIS) in 2009, and a sample of 757 households was selected. The statistical methods were frequency, percentile, mean, standard deviation, ${\chi}^2$, t-test, Pearson's correlation coefficient, and logistic regression analysis. The findings of this study are as follows. First, the percentile of preparation for living costs for old age was 49.9% for the middle-aged households. In terms of the types of preparation for living costs for old age, the results showed 61.6% of personal preparation, 33.9% of pension system, and 1.3% for children and relatives. In relation to the adequacy of the preparations for living costs for old age, preparations made by 57.4% of the middle-aged households were inadequate. Observing the minimum living costs for old age and adequate living costs after retirement for single and couple, the minimum living costs of the middle-aged households was 1.46 million won for couple and 0.91 million won for single. The adequate living costs for old age was 2.07 million won for couple and 1.34 million won for single. Second, there were 757 households with total education expenditure. Of these, 208 incurred annual expenditure on public education, and the annual expenditure for public education was 7.28 million won. There were 170 households with annual expenditure for private education, and the annual expenditure for private education was 2.50 million won. 243 households of middle-aged households had annual expenditure for human capital investment, including both public and private education, with annual expenditure for human capital investment for children of 7.82 million won. Furthermore, in the human capital investment factor, there was a difference in the middle-aged households' financial preparation for retirement according to their annual expenditure for human capital investment including both public and private education. In addition, there was a difference in financial preparation for retirement based on their public education expenditure. Third, in the logistic regression model 1, which included human capital investment, the significant variables affecting the preparation for retirement of the middle-aged households were as follows : annual household income, total amount of annual household income, experience of inadequate living costs, existence of financial assets, total amount of annual household savings, financial independence, adequate living costs (for single) for old age, and human capital investment. In the logistic regression model 2, which included annual expenditure for public education and annual expenditure for private education, the significant variables affecting the preparation for retirement of the middle-aged households were as follows : annual household income, total amount of annual household income, experience of inadequate living costs, existence of financial assets, total amount of annual household savings, financial independence, adequate living costs (for single) for old age, and annual expenditure for public education.

• 대한소아치과학회지
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• 제30권4호
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• pp.678-683
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• 2003

유아기 우식증의 새로운 정의와 진단기준을 적용하여, 익산시 3-5세 취학전 어린이 612명을 대상으로 중증 유아기 우식증의 유병률을 조사하고, 질문지 조사를 통하여 중증 유아기 우식증의 위험요인을 함께 조사하였다. 어린이들의 상악 유전치의 순면과 설면 및 인접면을 검사하고, 6개의 상악 유전치 중에서 한 개 이상의 우식와동이 있거나 우식으로 인해 상실되었거나 충전된 평활면이 있는 경우에 중증 유아기 우식증에 이환된 것으로 진단하였다. 중증 유아기 우식증의 유병률은 36-47개월이 20.8%, 48-59개월이 23.6%, 60-71개월이 30.8%이었고, 남아가 27.8%, 여아가 25.0%이었다. 재우기 위한 목적으로 수유한 경우의 유병률은 33.0%로서 그렇지 않은 경우의 23.0%보다 높았으며 유의한 상관성이 있었다(P<0.05). 잠든 후 수유를 즉시 중단한 경우의 유병률은 28.6%로서 그렇지 않은 경우의 66.7%보다 낮았으며, 유의한 상관성이 있었다(P<0.01). 어린이의 이를 닦기 시작한 시기에 따른 유병률은, 처음 이가 날 때가 21.5%, 앞니가 난 후가 25.2%, 어금니가 나는 중이 27.7%, 어금니가 난 후가 43.7%, 그 이후가 60.9%로서, 이를 닦기 시작한 나이가 늦어질수록 유병률이 증가하였으며, 유의한 상관성이 있었다(P<0.01). 주 보육자의 칫솔질 횟수가 규칙적인 경우의 유병률은 25.1%로서 불규칙한 경우의 34.0%보다 낮은 경향이 있었다(P<0.10). 주 보육자가 구강청결용품등을 사용하는 경우의 유병률은 21.8%로서 사용하지 않는 경우의 28.8%보다 낮은 경향이 있었다(P<0.10).

• Journal of Radiation Protection and Research
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• 제26권1호
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• pp.7-12
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• 2001

최근 개발된 방사선량 측정용 LiF:Mg,Cu,Na,Si TL 소자의 글로우 곡선, 방출스펙트럼, 광자에 대한 선량의존성, 에너지의존성 및 페이팅 등과 같은 물리적 및 선량계적 특성들을 연구하였다. LiF:Mg,Cu,Na,Si TL 소자는 LiF:Mg,Cu,Na,Si TL 분말에 압력을 가한 후 소결하는 방법으로 제조되었다. 방사선에 대한 특성을 알아보기 위하여 광자선 조사는 한국원자력연구소의 X선 발생 장치 및 $^{137}Cs$ ${\gamma}$선 원격조사장치를 이용하였으며, 사용된 광자선 에너지 범위는 20-662keV, 선량 범위는 $10^{-6}-10^{-2}\;Gy$이었다. 글로우 곡선은 수동형의 TLD 판독장치 (System 310, Teledyne)로 질소를 흘리면서 선형적인 가열률로 측정하였으며, TL 강도는 글로우 곡선을 전체 적분한 면적으로 평가하였다. $5^{\circ}C\;s^{-1}$의 선형적인 가열률로 측정한 글로우 곡선은 5개의 피크들로 분리되었으며, $234^{\circ}C$에 나타나는 주피크의 활성화에너지는 2.34 eV, 진동수인자는 $1.00{\times}10^{23}$이고, 방출스펙트럼은 410nm를 중심으로한 단일한 분포로 나타났다. 선량의존성은 100Gy 이상까지 선형성을 나타내었으며, $^{137}Cs$에 대한 저에너지 광자의 상대적인 에너지 반응값은 20% 범위 이내였다. 또한 실온에서 1년간 보관하였을 때, 시간경과에 따른 TL 감도의 감소가 거의 없는 좋은 페이딩 특성을 보였다.

• 한국조리학회지
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• 제18권5호
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• pp.16-32
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• 2012

본 연구의 목적은 외식프랜차이즈에서 본사의 영향전략이 가맹점의 영역초월행동에 어떠한 영향을 미치는지와, 본사의 영향전략이 가맹점의 영역초월행동에 미치는 인과관계에서 본사의 기업가지향성이 조절역할을 하는지, 및 본사의 기업가지향성이 가맹점의 영역초월행동에 어떠한 영향을 미치는지를 파악하는데 있다. 본 연구의 표본은 전국 외식프랜차이즈에서의 가맹점의 점주나 관리인이었으며 총 698부의 설문지를 회수하였다. 본 연구에서 사용된 통계분석방법은 빈도분석, 탐색적 요인분석, 신뢰도 분석, 위계적 회귀분석이었다. 통계분석 결과, 본사의 영향전략인 약속(${\beta}$=0.292), 위협(${\beta}$=-0.256), 권고(${\beta}$=0.200), 정보교환(${\beta}$=0.359), 요청(${\beta}$=-0.097), 법적소원(${\beta}$=-0.137)이 가맹점의 영역초월행동에 영향을 미쳤으며, 본사의 기업가지향성(${\beta}$=0.537)도 가맹점의 영역초월행동에 유의한 영향을 미치는 것으로 나타났다. 또한 본사의 기업가지향성은 약속측면(약속 x 본사의 기업가지향성; ${\beta}$=0.168)과 위협측면(위협 x 본사의 기업가지향성; ${\beta}$=-0.075)이 가맹점의 영역초월행동에 미치는 인과관계에서 조절효과를 가지는 것으로 나타났다. 이러한 결과를 바탕으로 한국의 외식프랜차이즈 가맹점들은 본사가 높은 기업가지향성을 가져 시장에서 긍정적인 성과를 획득하기 원하며, 동시에 영향전략에서 약속을 행하는 것을 선호하는 것으로 나타났다. 마지막으로 본 연구의 한계점과 미래연구의 방향이 서술되었다.

• 한국조리학회지
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• 제15권1호
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• pp.105-119
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• 2009

최근 생활 수준이 높아지고 건강과 웰빙에 대한 관심이 증가함으로써 고객들은 더욱 더 큰 역할을 기대하고 있다. 그러므로 고객들은 외식상품 개발에 적극적으로 참여하기를 희망한다. 이 연구의 목적은 외식상품 개발 시 고객 참여 전략에 대한 판별분석을 실시하였다. 통계기법은 신뢰성분석, 차이분석, 판별분석을 이용하였다. 조사는 2008년 7월 1일부터 7월 31일까지 서울과 광주 소재 외식산업체를 대상으로 350부 설문지를 배포하였으며, 이 중 정확하게 작성된 설문지 300부를 SPSS 12.0 패키지 프로그램을 사용하였다. 분석결과 외식상품 개발 시 적극적인 산업체와 소극적인 산업체 간에 시장지향성과 고객 만족에 유의한 차이가 나타났으며, 판별분석결과를 보면 고객 참여 전략을 소극적으로 실행하고 있는 외식기업은 고객만족 보다 시장지향성적인 경영 목표를 두고 있다. 또한 고객 참여 전략을 적극적으로 실행하고 있는 외식기업은 시장지향성 보다는 고객 만족에 경영 목표를 두고 있다. 그러므로 서비스 업종인 외식기업은 고객 만족이라는 경영 목표가 최우선이라면 고객 참여 전략을 적극적으로 도입해야 할 것이다.