• Journal of Positioning, Navigation, and Timing
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• 제12권4호
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• pp.423-430
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• 2023

One recent notable method for real-time elimination of ionospheric errors in geodetic applications is the Predicted Global Ionosphere Map (PGIM). This study analyzes the level of accuracy achievable when applying the PGIM provided by the Center for Orbit Determination of Europe (CODE) to the Korean Peninsula region. First, an examination of the types and lead times of PGIMs provided by the International GNSS Service (IGS) Analysis Center revealed that CODE's two-day prediction model, C2PG, is available approximately eight hours before midnight. This suggests higher real-time usability compared to the one-day prediction model, C1PG. When evaluating the accuracy of PGIM by assuming the final output of the Global Ionosphere Map (GIM) as a reference, it was found that on days with low solar activity, the error is within ~2 TECU, and on days with high solar activity, the error reaches ~3 TECU. A comparison of the errors introduced when using PGIM and three solar activity indices-Kp index, F10.7, and sunspot number-revealed that F10.7 exhibits a relatively high correlation coefficient compared to Kp-index and sunspot number, confirming the effectiveness of the prediction model.

• 대한영양사협회학술지
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• 제11권2호
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• pp.159-169
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• 2005

The purpose of this study was to assess the energy expenditure and investigate the relationship between related variables in 70 female university students. Resting energy expenditure estimated by Harris-Benedict formula, WHO/NAO/FAO formula and various formulas based on body weight and body surface area were 1366.9$\pm$74.4kcal/day, 1287.8$\pm$106.6kcal/day, 1171.4$\pm$155.8kcal/day and 1342.0$\pm$97.4kcal/day. Measured resting energy expenditure by indirect calorimetry(Model : Metavine and TrueOne2400) were 1582.0$\pm$150.1kcal/day and 1268.2$\pm$152.9kcal/day, respectively. Average step number per day was 11981.2$\pm$3014.4 steps and average step number per hour was 746.1$\pm$198.0 steps/hr. Daily energy expenditure by using Harris-Benedict formula, body weight formula, body surface area formula, WHO/NAO.FAO formula and 15-min check list formula were 2374.7$\pm$249.6kcal, 2033.5$\pm$313.2kcal, 2331.2$\pm$266.0kcal, 2240.8$\pm$185.5kcal and 2195.5$\pm$398.3kcal. Meanwhile energy intake of subjects was 1714.9$\pm$551.2 kcal. Daily energy expenditure has positive correlation(r=0.262) with daily step number. And there was significant positive correlations(r=0.35-0.68) between various daily energy expenditures and muscle mass. These results suggested that increase of daily step number by using pedometer is good method to increase daily energy expenditure. In particular, increase in step number can reinforce the amounts of muscle.

• 대한화학회지
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• 제53권4호
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• pp.453-465
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• 2009

본 연구에서는 한 가지 염으로 포화된 수용액에 다른 염을 녹이면 얼마나 녹을 것인가에 대한 초-중등 학생들과 교사들의 이해 정도가 낮은 이유를 알아보기 위하여 중등학교 교과서와 대학교 교재의 서술 내용을 조사하였다. 그 결과 중등학교 교과서와 대학교 일반화학 교재에서는 다른 염의 존재 여부와 상관없이 용해도는 일정함을 전제로 서술하고 있었으며, 대학교 물리화학 교재에서는 다른 염의 존재에 의해 용해도가 달라짐을 직접 언급하거나 이를 알 수 있는 내용이 서술되어 있었다. 그러나 물리화학을 이수한 사범대학 4학년 학생들을 대상으로 조사해본 결과 학생들의 대부분이 이러한 용해도 변화에 대한 설명을 하지 못하였다. 따라서 교사나 예비 교사들의 의문을 해소하기 위해 이온쌍 형성과 이온 세기 변화에 따른 용해도의 변화를 설명하고, 실제 실험 결과도 하나 제시하였다. 하지만 중등학교에서는 활동도 개념의 도입이 어려우므로 두 가지 염이 동시에 용해될 때의 용해도를 어떻게 가르칠지에 대한 논의가 필요한 것으로 생각된다.

• 대한화학회지
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• 제44권1호
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• pp.37-44
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• 2000

띠미로버섯의 에탄올 추출물 중 25-Epi, $3{\alpha}-carboxyacetylquercinic$ acid의 두 구조, 항균활성 및 항암활성을 연구하였다. 화합물 1의 녹는점과 분자량은 각각 $167{\sim}168^{\circ}C$, 572였고, 몰 흡광 계수는 208 nm에서 5,040이었다. 여러 분광학적 성질로부터 이는 24S, 25S, $3{\alpha}-carboxyacetylquercinic$ acid로 확인되었고, 곰팡이, 효모 및 세균들에 대한 항균활성과 항암활성($IC_{50}=64.5\;{\mu}M$)이 있었다. 화합물 2의 녹는점, 분자량 및 몰흡광 계수는 각각 $233{\sim}235^<\circ}$, 572 및 208 nm에서 5,080이었다. 이는 24S, 25R, $3{\alpha}-carboxyacetylquercinic$ acid로 확인되었고, 화합물 1과 서로 다른 항균활성을 보였다.

• Journal of Nutrition and Health
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• 제29권5호
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• pp.507-516
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• 1996

This study was undertaken to estimate seasonal variation of riboflavin status and investigate the relationship between riboflavin intake and its biochemical status in rural women. Dietary intake was measured by determining both 24hr recall method and conventient method. The riboflavin intake was also estimated by food frequency method. Ribofiavin biochemeical status was assessed by erythrocyte glutathione reductase activity coefficient(EGR AC) and urinary riboflavin excretion. All information was repeatly collected in three seasons ; farming season (June), harvest season(October), nonfarming season(February). Mean daily riboflavin intake was below RDA for Koreans in all seasons. Cereal & pulse, vegetable were the primary sources of riboflavin intake and provided above 60% of the total dietary riboflavin intake in all seasons. Riboflavin biochemical status was significantly different among seasons(EGR AC P<0.005, 24hr urinary riboflavin excretion P<0.05), and riboflavin biochemical deficiency was highest in February. The mean values of EGR AC revealed riboflavin deficiency in all seasons. However the mean values of urinary riboflavin excretion were within the normal range except 24hr urinary riboflavin excretion in February. On the basis of EGR AC criteria, 44.7% of subjects were at risk of deficiency in June, 44.7% in October, 81.6% in February. Result of individual riboflavin status assessed by EGR AC or 24hr urinary riboflavin excretion criteria was quite alike. Urinary riboflavin excretion per gram of creatinine underestimated riboflavin deficiency. Significant correlations were observed among biochemical indexes. It also appeared that riboflavin intake measured by food frequency method showed significant correlation with biochemical indexes, especially high correlation with EGR AC (P<0.001). The results indicated that the prevalence of riboflavin deficiency seems to be high among rural women in all seasons and the inadequacy of dietary riboflavin intake was reflected in the abnormalcy of riboflavin biochemical status assessed by EGR, AC. Therefore EGR AC seems to be more sensitive measure of impaired riboflavin status compared to urinary excretion.

• 한국식품영양과학회지
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• 제27권6호
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• pp.1244-1252
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• 1998

The purpose of this study is to evaluate the nutritional status of vitamin and minerals in the patients with alcoholic liver disease and to obtain the materials for nutritional education for alcoholics. The subjects consist of 80 patients with alcoholic liver cirrhosis(ALC) and 12 patients with alcoholic fatty liver(AFL). The control group included 57 alcoholics without liver disease(A), 32 patients with viral liver cirrhosis(VLC) and 194 normal men(NL). Biochemical evaluation of nutritional status was investigated by the analysis of blood samples. The frequency of vitamin B1 deficiency in the ALC, AFL and A groups as indicated by the erythrocyte transketolase activity coefficient were 46.0%, 66.7% and 57.9% respectively. The frequency of vitamin B2 deficiency in the ALC, AFL and A groups as indicated by the erythrocyte glutathione reductase activity coefficient were 9.8%, 8.3% and 38.6% respectively. Vitamin A deficiency was not detected in the alcoholic subjects. The frequency of vi tamin E deficiency in ALC, AFL and A were 96.3%, 66.7% and 86.0% respectively. The levels of plasma lipid peroxidation products were significantly higher in the alcoholic subjects than in the normal subjects. The frequency of subjects below normal range of hemoglobin were 85.0% in ALC, 50.0% in AFL and 31.6% in A. The frequency of copper deficiency in the ALC, AFL and A groups were 48.4%, 16.7% and 17.5% respectively. The frequency of zinc deficiency in the ALC, AFL and A groups were 83.8%, 41.7% and 66.7% respectively. Overall, the vitamin and minerals status of the alcoholic subjects in this study was evaluated to be very poor on the basis of biochemical assessments. The results suggest that alcohol abuse and poor dietary intake could cause malnutrition and may be important risk factors in causing alcoholic liver disease in alcoholics. In addition, vitamin B1, vitamin B2, Cu, Fe and antioxidant supplementation may be effective in nutritional therapy for chronic alcoholics.

• 한국화재소방학회논문지
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• 제29권5호
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• pp.1-6
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• 2015

인화점은 화재 및 액체의 폭발 위험의 가능성을 결정하는 데 사용되는 가장 중요한 물리적 특성이고, 산업공정에서 안정성 평가시 중요한 연소특성 가운데 하나이다. 따라서 본 연구는 4류 위험물 중 알코올계 혼합물인 {methanol + 1-butanol}, {ethanol + 1-butanol} 그리고 {2-propanol + 1-butanol} 이성분계 101.3 kPa에서 최소인화점을 SETA closed cup flash point tester를 이용하여 측정하였다. 각 이성분계에 대하여 Wilson, NRTL 및 UNIQUAC 파라미터를 이용하여 혼합물에 대한 인화점 예측하고 실험 결과와 비교하였다. 비교결과 모든 예측값과 실험값은 유사한 값을 보였고 편차가 1.14 K 이내의 결과를 보였다.

• 한국융합학회논문지
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• 제7권5호
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• pp.237-246
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• 2016

본 연구의 목적은 노인의 우울, 늙어감에 대한 행복감, 자아존중감, 생활만족도, 사회참여, 일상생활 활동장애 정도를 파악하고 노인의 우울에 미치는 요인들을 분석하는데 있다. 연구 자료는 기술통계, t-test, ANOVA, Pearson's Correlation Coefficient, Stepwise multiple regression analysis를 이용하여 분석하였다. 노인의 우울에 가장 영향이 높은 변수는 자아존중감 27.9%(${\beta}=-.318$, p<.001), 생활만족도 5.5%(${\beta}=-.248$, p<.001), 늙어감에 대한 행복감 4.1%((${\beta}=-.200$, p<.001), 일상생활 활동장애 1.6%(${\beta}=.128$, p=.026) 순으로 이들 네 개의 변수가 노인의 우울을 총 39.1% 설명하는 것으로 나타났다. 따라서 노인의 우울을 감소시키고 자아존중감과 늙어감에 대한 행복감을 향상시키기 위한 차별화된 교육프로그램을 개발하는 것이 필요하다.

• Asian Pacific Journal of Cancer Prevention
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• 제14권5호
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• pp.2777-2782
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• 2013

The aim of the present study was to assess criterion validity and external reliability of a questionnaire on risk factors for breast cancer. Materials and Methods. Women with breast cancer diagnosis (the cases) (N=40) and matched individuals without cancer (the controls) (N=40) were asked to fill in a questionnaire twice: on a day of admission to hospital (Q1) and on a day before discharge (Q2), with a time interval of 4-6 days. The questionnaire included questions (N=150) on demographic and socioeconomic factors, diseases in the past, family history of cancer, woman's health, smoking, alcohol use, diet, physical activity, and work environment. Criterion validity of the questionnaire Q2 relative to reference questionnaire Q1 was assessed with the Spearman correlation coefficient (SCC); external reliability of the questionnaire was measured in terms of the intraclass correlation coefficient (ICC). Statistical analysis was performed with SPSS 16. Results. The responses to most of the questions on socioeconomic factors, family history on cancer, female health, lifestyle risk factors (smoking, alcohol use, physical activity) correlated substantially in both the cases and the controls with SCC and ICC>0.7 (p<0.01). Statistically non significant relationships defined only between the responses on amount of beer the cases drank at the ages up to 25 years and 26-35 years as well as time of use of estrogen and estrogens-progestin during menopause by the cases. Moderate and substantial SCC and ICC were determined for different food items. Only the response of the cases on veal consumption did not correlate significantly. Conclusions. The questionnaire on breast cancer risk factors is valid and reliable for most of the questions included.

• 한국화재소방학회논문지
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• 제13권1호
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• pp.11-19
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• 1999

인화점은 일반적으로 가연성액체의 화재 및 폭발의 위험지수로써 사용된다. 인화점의 구분은 혼합용제와 같은 가연성액체를 안전하게 취급하기 위해서 매우 중요하다. 순수성분 및 혼합용제의 인화점은 라울의 법칙, 달톤의 법칙, 르 샤틀리에 법칙 그리고 활동도계수 모델을 사용함으로써 계산할 수 있다. 본 연구에서는 가연성 2성분계인 메칠에칠케톤과 톨루엔계의 하부인화점과 상부인화점의 실험자룔르 라울의 법칙과 van Laar식에 의해 계산된 값과 비교하였다. 순수물질의 실험자료는 증기압과 폭발한계에 의해 계산된 예측값과 일치하였다. 메칠에칠케톤과 톨루엔계의 하부인화점의 실험자료는 라울의 법칙에 의해 예측된 값과 일치하였고, 상부인화점의 실험자료는 van Laar식에 의해 예측된 값과 일치하였다. 따라서 제시한 방법론에 의해 가연성혼합용제의 인화점 실험자료의 신뢰도 평가가 가능하다.