• 대한토목학회논문집
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• 제31권2A호
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• pp.129-136
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• 2011

최근 대기오염 물질을 제거하기 위하여 $TiO_2$ 등의 광촉매 재료를 사용한 기능성콘크리트에 대한 연구가 활발히 이루어지고 있다. 이들 연구에서 $TiO_2$의 흡착은 콘크리트에 직접 혼합하거나, 현탁액을 표면에 직접 도포하는 방법을 사용하고 있다. 이 중 콘크리트에 $TiO_2$를 직접 혼합하는 방법은 $TiO_2$의 사용량에 비하여 효능이 떨어져 표면에 직접 도포하는 방법이 많이 이용된다. $TiO_2$의 표면도포는 광촉매의 활성화와 접착성 증대를 위하여 $400^{\circ}C$ 이상의 고온 열처리를 실시하게 되며, 이는 콘크리트 수화생성물의 탈수 수축으로 내부균열을 발생시키는 원인이 되기도 한다. 이에 이 연구에서는 $TiO_2$의 저온도포가 가능한 Sol-gel법으로 $TiO_2$를 제조하였으며 펄라이트 사용 경량골재콘크리트에 저온 고정화하여 $TiO_2$ 도포 성능을 평가하였다. 또한 펄라이트 입경을 2.5~5.0 mm와 5.0 mm이상으로 구분하여 펄라이트 입경, $TiO_2$ 혼입방법과 혼입률 및 시간경과에 따른 $CH_3CHO$ 제거 특성을 검토하였다. 실험결과, Sol-gel법으로 제조한 $TiO_2$를 $120^{\circ}C$에서 저온 도포할 때 XRF 정량분석에서 $TiO_2$ 38%, $SiO_2$ 29%, CaO 18% 순으로 나타나 $TiO_2$ 도포율은 높게 나타났다. 또한 펄라이트 입경 2.5~5.0 mm에서 $TiO_2$를 저온도포한 경량골재콘크리트의 $CH_3CHO$ 제거 특성은 Sol-gel법으로 제조된 $TiO_2$를 7% 표면 도포하였을 경우 94%로 나타나 10%를 혼입할 때 72%에 비해 약 20%정도 높게 나타났다. 또한 펄라이트 입경 5.0 mm이상에서 $TiO_2$를 10%로 치환하여 혼합하였을 경우 $CH_3CHO$ 제거율은 69%로 펄라이트 입경 2.5~5.0 mm에 대한 72%와 비슷하게 나타나 펄라이트 입경이 $CH_3CHO$ 제거율에 미치는 영향은 크지 않았다. 시간 경과에 따른 $CH_3CHO$ 제거 특성은 전 시험편의 10시간 평균 제거율이 20시간 전체 제거율의 84% 수준으로 나타나 반응 초기에 제거율이 높은 것으로 나타났다.

• 한국지역사회생활과학회지
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• 제22권1호
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• pp.155-161
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• 2011

This study was designed to present the preferred indoor temperature of college students in summer based on their body composition. A total of 19 subjects, 10 females and 9 males, participated in this study. They sat in a climatic chamber controlled at $27^{\circ}C$ wearing a short sleeved shirt and short trousers. The air temperature decreased by $0.5^{\circ}C$ every 10 minutes until it reached $24^{\circ}C$. Oxygen uptake, rectal temperature, and skin temperature, subjective sensation were measured and recorded. Females increased the rectal temperature and decreased mean skin temperature in an air conditioned environment, showing better physiological responses. But they felt more thermal discomfort than males. The preferred indoor temperature of college students in summer was $25.3^{\circ}C$, $25.7^{\circ}C$ for females and $24.97^{\circ}C$ for males.

• Clinical and Experimental Pediatrics
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• 제48권7호
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• pp.766-771
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• 2005

목 적 : 류코트리엔 수용체 길항제는 천식의 병리 반응에 관여하는 cysteiny leukotriene의 생성과 작용을 억제하여 급성기 천식 증상의 치료와 천식 증상의 조절 요법에 사용할 수 있다. 본 연구에서는 소아 천식환자에서 cysteinyl leukotriene 생성에 관여하는 $LTC_4S$ 유전자 다형태와 류코트리엔 수용체 길항제인 montelukast의 임상적 효과를 조사하여 약물유전학적 연관성 유무를 알고자 하였다. 방 법 : 환자군은 경증 지속성 천식과 중등증 지속성 천식환자 161명을 대상으로 하였고, montelukast 5 mg을 하루에 한 번씩 총 8주 동안 투여하였다. $LTC_4S$ 유전자 다형태는 restriction fragment length polymorphism을 이용하여 조사하였다. 결 과 : 대조군에서 LTC4S 유전자형의 분포는 A/A, A/C, C/C가 각각 74.0%, 22.6%, 3.4%였고, 환자군에서는 A/A, A/C, C/C가 각각 70.8%, 23.6%, 5.6%였다. 두 군의 유전자형 분포는 통계적으로 유의한 차이를 보이지 않았고, $LTC_4S$ 유전자형 분포와 천식의 중증도 사이에도 유의한 차이가 없었다. 반응군에서는 경증 지속성 천식환자가 반응이 없는 군에서는 중등증 지속성 천식환자가 더 많았다. 전체 소아 천식환자군에서는 montelukast에 대한 반응군과 반응이 없는 군 사이에 $LTC_4S$ 유전자형에 따른 차이는 없었다. 경증 지속성 천식환자의 반응군에서 adenine 대립유전자를 가진 환자가 많았으나, 중등증 지속성 천식환자에서는 유전자형에 따른 반응군과 반응이 없는 군의 유의한 차이가 없었다. 결 론 : 본 연구에서 소아 경증 지속성 천식환자의 경우에는 통계적으로 adenine 대립유전자가 montelukast에 대한 임상적 효과를 예측할 수 있는 인자라고 할 수 있으나 전체 소아 천식환자에서는 $LTC_4S$ 유전자 다형태와 montelukast의 임상적 효과와의 연관성은 통계적으로 없었다.

• 대한지역사회영양학회지
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• 제3권5호
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• pp.695-706
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• 1998

This study was designed to investigate the associations of the percent body fat dietary intake, plasma lipoprotein profile, lipoprotein(a), and plasminogen activator inhibitor-1(PAI-1) concentrations of 1982 Korean subjects(men : 1000 and women : 982) between the ages of 40 and 59 years. The dietary assessment consisted of twenty-four hour dietary records and food frequency questionnaires. The subjects were identified into one of the five rating groups of % body fat : lean, underweight, normal, overweight and obese groups. The biochemical assessment included measurements of plasma total cholesterol(TC), HDL-cholesterol(HDL-C), LDL-cholesterol(LDL-C), triglyceride(TG), lipoprotein(a)(Lp(a)), and PAI-1. With respect to the ratio of percent energy intake of carbohydrate : protein : fat of the normal group of the women was 62% : 17% : 20%, respectively. Women apparently had a higher intake of carbohydrates than men(52% : 17 : 20%) did. There was a linear relationship between energy intake and % body fat in both mean and women(with the exception of the underweight group of women). The relationship of % body fat of men to the protein and fat intake was higher than that of the carbohydrate intake. Of the men in the study, intakes of energy, protein and alcohol were positively correlated to % body fat. In women, energy, carbohydrate and protein intake were positively correlated to % body fat, however, the fat, cholesterol and alcohol intake did not show any correlation to the % body fat in women. This study showed that % body fat was positively correlated with plasma TC, LDL-C, PAI-1 levels, and TG, but the % body fat was negatively correlated with plasma HDL-C level in both men and women. These results indicated that the high energy intake of obese or overweight subjects might contribute to several of the biochemical indices fo coronary heart disease(CHD) risk. In conclusion, increased energy intake is associated with overweight or obesity in middle aged Korean people. There was no relationship between % energy intake of fat and % body fat in the study, in middle-aged Korean men and women. The plasma lipid profile and PAI-1 level thought to be the risk factors of CHD were positively associated with percent body fat in middle aged Korean people.

• Journal of the Korean Wood Science and Technology
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• 제36권5호
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• pp.56-65
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• 2008

In this paper experimental results are presented for the rheological behavior of high-solids saccharification of mixed northeast hardwood as a model feedstock. The experimental determination of the viscosity, shear stress, and shear rate relationships of the 10 to 20 percent slurry concentrations with constant enzyme concentrations were performed under variable rotational speed of a viscometer (2.0 to 200 RPM) at combined temperatures (50 to $30^{\circ}C$) for the initial four hours. The viscosities of saccharification slurries observed were in the ranges of 0.024 to 0.028, 0.401 to 0.058, and 0.840 to 0.087 Pa s for shear rates up to 100 reciprocal seconds at 10, 15, and 20 percent initial solids (w/v) respectively. The fluid behavior of the suspensions was modeled using the power-law, the Herschel-Bulkley, the Casson, and the Bingham model. The results showed that broth slurries were pseudoplastic with a yield stress. The model slope increased and the model intercept decreased with increasing fermentation time at shear rates normal for the fermentor. The broth slurries exhibited Newtonian behavior at high and low shear rates during initial saccharification process. The solid particle size ranged from 57.8 to $70.0{\mu}m$ for $40^{\circ}C$ and from 44.0 to 57.5 11m for combined temperatures at 10, 15, and 20 percent initial solids (w/v) respectively.

• 산업경영시스템학회지
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• 제4권5호
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• pp.11-14
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• 1981

This study intends to decide the economic sample size based on the cost of sampling Inspection for destructive testing. The marginal percent defective is used as the lot tolerance percent defective (LTPD), and the Newton's iterative method is adopted to calculate the optimum sample size(n), given by the consumer's risk($\beta$ - risk) and the acceptance number(c).

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2004년도 춘계 학술발표회 제16권1호
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• pp.360-363
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• 2004

The effectiveness of Meta-Kaolin to prevent detrimental expansion due to alkali-silica reaction was investigated through the ASTM C 1260 method. Reactive aggregate used is a metamorphic rock. The replacement proportions of portland cement by Meta-Kaolin were 0, 5, 10, 15, 25 and 35 percent, respectively. The results indicate that 25 percent replacement of portland cement by Meta-Kaolin seems to be most effective to reduce alkali-silica reaction expansion under this experimental conditions.

• 대한지역사회영양학회지
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• 제13권3호
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• pp.323-333
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• 2008

The aim of this study was to measure and compare nutrient intake, anthropometric measurements and serum indices by percent body fat as one of the index of obesity degree in female college students. Additionally we attempted to investigate percentile distribution of fat free mass index (FFMI) and fat mass index (FMI) for developing reference values for these two parameters. The subjects were 91 female college students who were classified to 4 groups according to the percentile of percent body fat (Group1: 25 th < percentile of percent body fat, Group 2 : 25 th ${\le}$ percentile of percent body fat < 50 th, Group 3 : 50 th ${\le}$ percentile of percent body fat < 75 th, Group 4 : percentile of percent body fat ${\ge}$ 75 th). The mean percent body fat and body mass index were 28.2%, $20.5 kg/m^2$ respectively. The mean energy intake was 1707 kcal(81% of KDRIs) and vitamin C, folate, Ca and Zn intake were 73.9%, 54.7%, 79.6%, 97.5% of KDRIs respectively. Most nutrient intake (energy, carbohydrate, cholesterol, fatty acid, Ca, Fe) of G4 was lower than that of G1, G2 and G3. Serum HDL-cholesterol concentration was significantly lower in G4 than G1, G2, G3 and it tended to increase as percent body fat decreased. LDL/HDL, A1 of G4 were significantly the highest among the 4 groups and increased as percent body fat increased. The mean fat free mass index and fat mass index were $14.5 kg/m^2$, $6.0 kg/m^2$ respectively. The criteria of sarcopenic obesity which has been defined as under 25 th percentile of FFMI and below 75 th percentile of FMI were shown $12.8 kg/m^2$, $8.2 kg/m^2$ respectively in this study. In conclusion, we should continue to more systematically research on the studies of new obesity measurement which includes FFMI and FMI as one of the variables. And the public education for weight control that emphasizes both the understanding of body composition and the importance of nutrition balance is also required.

• Clinical and Experimental Pediatrics
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• 제49권8호
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• pp.839-844
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• 2006

목 적 : 발열을 주소로 소아응급실에 내원한 소아의 임상적 특성에 대하여 조사를 하고자 연구를 시행하였다. 방 법 : 2004년 9월부터 2005년 8월까지 일산백병원 소아응급실에 내원한 8,881명의 환아와 이 중 $38.3^{\circ}C$이상의 발열을 주소로 내원한 1,764명의 환아를 대상으로 발열 환아의 발생 빈도, 월별 분포, 연령별 분포, 진단명을 조사 분석하였다. 결 과 : 조사 기간동안 소아응급실에 내원한 8,881명 중 1,764명이 발열로 내원하여 발열환자의 빈도는 19.9%이었고, 1,764명 중 26.4%가 입원하였다. 내원 발열 환아가 가장 많았던 연령군은 12-23개월 군이었고, 4-11개월 군과 2세 군이 뒤를 이었다. 가장 많은 진단명은 급성 인두염이었고, 급성 장염, 폐렴도 흔한 진단이었다. 연중 발열 환자가 가장 많았던 시기는 4-7월이었고, 이 중 5월에 발열 환자가 가장 많았다. 발열환자의 빈도는 8월이 가장 높았으나 통계적 의미는 없었으며, '봄 여름군', '가을 겨울군'으로 나눠서 비교한 발열환자의 빈도는 통계적으로 의미 있는 차이가 있었다. 결 론 : 소아 응급실에서 발열 환아의 연중 발생빈도는 19.9%이었고, 12-23개월의 환아가 빈도가 높았으며, 5월에 발열 환아가 가장 많았다. 본 연구에서도 급성 인두염, 급성 장염, 급성 비인두염, 급성 기관지염과 같은 비응급 질환의 비율이 높았다. 응급실에 내원하는 비응급 질환을 줄이기 위해 의료체계 개선과 보호자 교육이 필요할 것으로 생각된다.

• Journal of Nutrition and Health
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• 제7권3호
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• pp.1-13
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• 1974

The relative state of human iron storage may be ascertained more reliably through determination of the serum iron, iron binding capacity, transferrin saturation and absorption of radioactive iron in conjunction with studies of red cell morphology than from the study of red cell morphology alone. Recent investigations have shown that there is an increase in red cell protoporphyrin concentration in iron deficiency anemia. The significance of the red cell protoporphyrin has been discussed greatly during the years since its discovery. Two of the main factors which appear to influence the amaunt of protoporphyrin are increased erythropoiesis and factors interfering with the utilization of iron in the synthesis of hemoglobin, and iron deficiency. Recently Heller et al. have described a simplified method for blood protoporphyrin assay and this technique could be used assess nutritional iron status, wherein even minor insufficiencies are detectable as increased protoporphyrin concentrations. Based on the evaluation of the relationship between nutritional iron status and red cell protoporphyrin as an index suitable for the detection of the iron deficiency is described in this paper. RESULTS 1. Hemoglobin Concentrations and Anthropometric Measurements. The mean and standard deviations of the various anthropometric measurements of different age and sex groups are shown in table 1. There measurements have been compared with the Korean Standard. In the absence of local standards for arm circumference and skin-fold thickness over triceps, they have been compared with the standard from Jelliffe. Table 2,3, and 4 give anthropometric measurements and frequency (%) of anemia in children surveyed. The mean height of the children studid was 10 to 20 percent; below the Korean Standard. The distribution of height below 80 percent of the Standard was 21.2 percent, however, among anemic group this percentage was 27.7 percent. In general, the mean weight of the children was 10 to 15 percent below the Korean Standard. The percentage of children with weight less than 80 percent of the Standard was about 35 percent. But in the anemic group of the children, this percentage was 44 percent. The mean arm circumference was about 15 percent lower than the Jelliffe's standard. 61.2 percent of the children had values of arm circumference below 80 percent of the standard. Children with low hemoglobin levels, this percentage was 80 percent. The mean skinfold thickness over the triceps of the children studied was about 25 Percent lower than the Jelliffe's standard and 61.2 percent of the children had the value less than 80 percent of the standard. Among anemic children, this percentage was 70.8%. As may be seen from table 5, the mean hemoglobin concentration of the total group was 11.3g/100ml. Hemoglobin concentration was less than 11.0g/100ml. in 65(36.5%) of the 178 children. The degree of anemia in most of these children was mild with a hemoglobin level of less than 8.0g/100ml. found in only one child. In general, the prevalence of anemia was high in female children than male and decreased its frequency with increasing age. Relatively close relationship was observed between hemoglobin level and anthrophometric measurements especially high between arm circumference and skinfold thickness and hemoglobin but very low in height and low in weight and hemoglobin level, estimated by chi-square value. II. Serum iron, Transferrin saturation (1) Serum iron, and transferrin saturation Serum iron, transferrin saturation and red cell protoporphyrin concentrations were estimated in sub-sample of 84 children from 1 to 6 years and 24 older children between 7 and 13 years of age. The findings are presented in table 6. The mean serum iron concentration of the total group was 59ug/100ml. However, the level incrased with age from 36.6ug/100ml. (1-3years) to 80.8ug/100ml. (7-13 years). 60 percent of these children had a serum iron level less than 50ug/10ml. in the 1-3 years age group and 31.4 percent for 4-6 years group. These contrast with the finding of 12.5 percent anemic children in the 7-13 years age group. The mean transferrin saturation for the total group was 18.1 percent and frequency of anemia by transferrin saturation was observed same pattern as serum iron concentration. (2) Red cell protoporphyrin concentrations. (a) Red cell protoporphrin levels of children: Red cell protoporphyrin and other biochemical data are shown in table 4. The mean concentration in red cell of all children was fround 46.3ug/100ml. RBC. and differences with age groups were observed; in the age group 1-3 years, the mean concentration was $59.5{\pm}32.14$ ug/100ml. RBC; 4-6 years $44.1{\pm}22.57$ ug/100ml. RBC. and 7-13 years, $39.0{\pm}13.56$ ug/100ml. RBC. (b) Normal protoporphyrin values in adults: It was observed that in 10 normal adult males studied here the level of protoporphyrin in red cell ranged from 18 to 54 ug/100ml. RBC. and the mean concentration was $47.5{\sim}14.47$ ug/100ml. RBC. Other biochemical determination made on the same subjects are presented in table 8. (c) Red tell protoporphyrin concentration of occupational blood donors: The results of analyses for red cell protoporphyrin as well as serum iron, transferrin saturation and hemoglobin in the 76 blood donors are presented in table 7 and 8. In this experiment, donors were selected at random, however, most of them bled repeatedly because of poor economic situation, I doubt. Table 9 shows the distribution of red cell protoporphyrin concentration and hemoglobin concentration of occupational donors. The mean hemoglobin value for the total was 11.9 g/100 ml. When iron deficiency anemia is defined as a transferrin saturation below 15%, prevalence of anemia was 47.4 percent and the mean serum iron was 27.1ug/100ml. and red cell protoporphyrin, 168.3ug/100ml. RBC. However, mean serum iron and protoporphyrin concentration of above 15% transferrin saturation were 11.6 ug/100 ml. and 58.8 ug/100 ml. RBC. respectively. The mean Protoporphyrin concentration of non-anemic (above 15% transferrin saturation) donors was slightly higher than the results of normal adult males.