• 제목/요약/키워드: Mass and frequency ratio

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동해 울릉분지의 사면안정성 및 쇄설류 퇴적체의 발달 (Slope Stability and Development of Debris Flow Deposit in the Ulleung Basin, East Sea)

  • 이선종;이정민;유동근;이고은;박수철
    • 자원환경지질
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    • 제50권2호
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    • pp.129-143
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    • 2017
  • 동해 울릉분지 남서부의 천부퇴적층은 대부분 사면사태와 쇄설류 퇴적체로 구성되어 있으며 주로 사면붕괴에 의해 야기된다. 따라서 쇄설류 퇴적체에 대한 연구는 지질재해 및 해저면의 안정성을 연구하는 측면에서 중요한 의미를 갖는다. 본 논문에서는 다중빔 음향측심자료를 이용하여 울릉분지의 흐름집적도 및 사면붕괴 취약성도를 작성하였다. 또한, 탄성파 탐사자료를 활용하여 동해 울릉분지의 최상부층에 존재하는 쇄설류 퇴적체의 분포 및 특성을 연구하였다. 사면붕괴 취약성도는 사면붕괴를 야기하는 각 요소별(경사, 경사방향, 곡률 그리고 수류력지수) 빈도비로 계산되었다. 이러한 결과는 동해 울릉분지의 남쪽과 서쪽 대륙사면에서 사면붕괴가 발생할 확률이 높은 것을 지시해준다. 사면붕괴로 야기되는 퇴적체의 흐름(쇄설류)은 사면기저부를 거쳐 울릉분지의 북서쪽 및 북쪽지역으로 수렴하고 있음을 보여준다. 탄성파 자료 분석에 의하면 연구지역의 최상부층에 분포하는 쇄설류 퇴적체는 총 4개의 퇴적단위로 구분된다. 이러한 퇴적단위의 분포는 흐름집적도와 사면붕괴 취약성도와 연계되어 발달하고 있는 것으로 보인다.

향판용(響板用) 관행수종(慣行樹種)과 대체가능수종(代替可能樹種)의 자유진동적(自由振動的) 성질(性質)에 관한 연구(硏究) (Studies on The Free Vibrational Properties of Traditional and Replaceable Species for Sounding Board)

  • 강욱;정희석
    • Journal of the Korean Wood Science and Technology
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    • 제16권3호
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    • pp.48-64
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    • 1988
  • This study was carried out to investigate the free vibrational properties of traditional and replaceable species for sounding board, using piezoelectrical accelerometer and signal analyzer. In the study, the frequency equations of free-free beam carrying a concentrated mass in the transverse vibration and of free-mass beam in the longitudinal vibration were used. The results obtained were as follows. 1. Average values of dynamic modulus of rigidity of Korean commercial species measured were as follows. Paulownia tomatosa (Thunb.) Steudel: $5.590\times10^9\;dyne/cm^2$ Tilia amurensis Rupr.: $5.414\times10^9\;dyne/cm^2$ Macckia amurensis Rupr.: $10.044\times10^9\;dyne/cm^2$ Fraxinus mandshurica Rupr.: $8.876\times10^9\;dyne/cm^2$ Ulmus davidiana var.japonica Nakai: $8.677\times10^9\;dyne/cm^2$ Pinus rigida Miller: $6.33\times10^9\;dyne/cm^2$ Fraxinus rhynchophylla Hance: $4.666\times10^9\;dyne/cm^2$ 2. The ratio of dynamic transverse Young's modulus to dynamic modulus of rigidity, $E_T/G_{LT}$, was 24.922 for Fraxinus rhynchophylla Hance, which was the highest, 7.317 for Paulownia tomentosa (Thunb.) Steudel, which was the lowest among Korean commercial species measured. 3. The value of longitudinal dynamic Young's modulus was about 3.7% and 19.8%, respectively, higher than those of transverse dynamic and static Young's modulus. The value of transverse dynamic Young's modulus was about 15.5% higher than that of static Young's modulus. 4. Predicted value of MOR in terms of correlation coefficient by transverse dynamic Young's modulus was slightly higher than that of static Young's modulus, but no significance was found out. 5. Transverse dynamic Youne's modulus was $(2.002\pm0.288)\times10^{11}\;dyne/cm^2$ for Fraxinus mandshurlca Rupr., which was the highest, $(0.601\pm0.100)\times10^{11}\;dyne/cm^2$ for Paulownia tomentosa (Thunb.) Steudel, which was the lowest among Korean commercial species measured. The sound velocity of sitka spruce was 5,685 m/sec, which was the highest. 6. Internal friction of Paulownia tomentosa (Thunb.) Steudel was shown the lowest value among Korean commercial species, $(8.795\pm1.795)\times10^{-3}$, but was higher than that of sitka spruce, $(7.331\pm0.991)\times10^{-3}$. Internal friction was shown negative correlation with density and dynamic Young's modulus, respectively. 7. K value was affected largely by internal friction and was the highest, $2.225\times10^8$ for Paulownia tomentosa (Thunb.) Steudel and was the lowest, $0.550\times10^8$ for Fraxinus rhynchophylla Hance. K value of Paulownia tomentosa (Thunb.) Steudel was higher than that of sitka spruce and K values of melapi and cottonwood, which have been considered to be replaceable species with sitka spruce in the piano industry, were lower than those of Paulownia tomentosa (Thunb.) Steudel and mill amurensis Rupr.

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알칼리막 연료전지용 전극의 제조방법에 따른 전기화학적 특성 분석 (Electrochemical Characteristics of Electrode by Various Preparation Methods for Alkaline Membrane Fuel Cell)

  • 육은성;이혜진;정남기;신동원;배병찬
    • 전기화학회지
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    • 제24권4호
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    • pp.106-112
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    • 2021
  • 최근에 알칼리막연료전지의 막전극접합체에서 이오노머에 의한 촉매 피독에 대한 연구 결과들이 보고되고 있다. 본 연구에서는 이를 해결하기 위해서 전극 제조 시에 사용되는 유기용매의 성분을 조절하여 막전극접합체의 성능을 향상시키고자 하였다. Fuma-Tech사의 상용 이오노머를 사용하여 N-Methyl-2-pyrrolidone (NMP)와 Ethylene glycol (EG)를 이용한 4가지의 혼합용매를 제조하였다. 혼합용액을 이용하여 제조된 캐소드 전극은 NMP기반의 상용 이오노머에 비해서 약 36%의 향상된 분극성능을 나타내었다. 이것은 용매의 종류에 따른 이오노머의 분산성 차이에 따른 결과로 추측되며 비균일성 분포의 이오노머가 전극의 성능을 향상시키는 것으로 관찰되었다. 이에 관한 원인분석을 위해서 막전극 접합체의 고주파 저항, 내부저항 보정 분극곡선, Tafel 기울기, Mass activity 및 임피던스 분광법을 사용하여 특성 분석을 실시하였다. 이오노머의 비용매의 비율 증가에 따라서 캐소드 전극 성능이 개선되는 것을 확인하였고, 이것은 이오노머의 입도 분포에 따라서 촉매의 피독이 감소되는 결과로 판단된다.

외식 빈도에 따른 대전시민의 영양상태 비교 (Comparison of Nutritional Status of the Daejeon Metropolitan Citizens by Frequency of Eating Out)

  • 서윤석;강지현;김한숙;정영진
    • Journal of Nutrition and Health
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    • 제43권2호
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    • pp.171-180
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    • 2010
  • 외식과 건강상태와의 관련성을 파악하고자 대학병원 건강검진센터에 내원한 20세 이상의 대전시민 137명을 대상으로 2008년 12월 6일부터 2008년 12월 15일까지 외식빈도와 체위, 혈압 및 혈청성분, 영양소 식품군 섭취량을 조사하고, 외식 빈도를 주 1회 미만, 주 1회, 주 2~3회, 주4회 이상의 4개 구간으로 분류하여 외식빈도에 따른 건강 및 영양상태의 차이를 비교하였다. 1) 외식 빈도에 따라 체위와 혈압, 혈청지질과 혈당 수준, 혈청 GPT와 GOT활성도의 평균치가 모두 정상 범위 내에 속하면서 외식 빈도가 높은 주 2~3회 외식군에서 수축기 혈압과 혈청LDL콜레스테롤과 혈청총콜레스테롤 농도가 높은 경향을 보였고, 혈청중성지방은 낮은 경향을 보였다. 2) 총단백질 (p < 0.01), 동물성단백질 (p < 0.01), 동물성 지방 (p < 0.05), 인 (p < 0.05), 비타민 $B_2$ (p < 0.05)의 평균 섭취량은 외식 빈도가 높은 주 4회 이상 외식군에서 높게 나타났으며, 비타민 C (p < 0.05)의 평균 섭취량은 외식 빈도가 낮은 주 1회 미만 외식군에서 높았다. 3) 탄수화물 에너지 비율은 주 1회 미만 외식군에서 높았고 (p < 0.001), 단백질 에너지 비율은 주 4회 이상 외식군에서 높았다 (p < 0.01). 4) 외식빈도에 따라 영양소의 평균필요량이나 충분섭취량 미만자의 분포에서 칼륨은 주 1회 미만 외식군에서 부족자의 비율이 높았고 (p < 0.05), 식이섬유소 (p < 0.05), 비타민 C (p < 0.05)는 주 4회 이상 외식군에서 부족자의 비율이 높았다. 5) 음료 차류 및 주류의 섭취량은 주 4회 이상 외식군에서 주 4회 미만 외식군들에 비해 높게 나타났으며 (p < 0.01), 감자 및 그 제품류는 주 2~3회 외식군에서 높게 나타났다 (p < 0.05). 또한 총동물성식품군, 기타식품군 중 음료 차류 주류의 섭취량은 주 4회 이상 외식군에서 다른 외식군보다 높았다 (p < 0.01). 비록 유의적인 차이는 나타나지 않았으나 채소류 및 과실류, 총식물성식품군의 섭취는 주 1회 미만 외식군에서 높은 경향을 보였고, 당류와 유지류의 섭취는 주 4회 이상 외식군에서 높은 경향을 보였으며, 육류, 어패류, 우유류는 주 2~3회 이상 외식군에서 높은 경향을 나타내었다. 위의 결과를 종합해 볼 때 외식횟수가 과다하면 총동물성 식품군과 음료 차류 주류 등의 기타식품군의 섭취를 증가시켜 총단백질, 총지방, 인의 과다 섭취를 초래하고, 비타민 C와 철분, 아연의 미량영양소의 섭취부족을 초래하는 것으로 나타나서 비타민 C가 많은 채소류 음식 등 식물성 식품의 식단을 보강시키도록 요식업체에 대한 계몽과 지도가 필요한 것으로 보여진다.

익산지역 초등학교 고학년의 비만지표별 비만도와 식습관에 대한 연구 (Determining the Frequency of Obesity and Eating Habits of Older(4th, 5th, 6th grade) Elementary School Students in Iksan City by Some Obesity Indices)

  • 주은정;김인숙;김영순;서은아
    • 대한지역사회영양학회지
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    • 제6권1호
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    • pp.16-27
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    • 2001
  • The purpose of this study is to determine the prevalence of obesity and to examine the eating habits of elementary school students in Iksan dity. The study was carried out on 292 students(male: 151, female : 141)in May of 1997. The average height and weight of the subjects were 141 cm and 37kg in males and 142 cm and 36kg in females, which were similar to the average of Chonbuk. A Weight/Length Index(WLI), Broca Index, Rohrer Index(RI), Body Mass Index(BMI) and Waist Hip Ratio(WHR) were used as an obesity index to classify degree of obesity. WLI, Broca Index and RI were proper for judging child obesity and strict judgments were conducted in the order of RI, WLI and Brcoa Index. The subjects were classified as 30.8% underweight, 43.5% normal, 8.2% overweight and 17.5% obese by WLI and there were significant differences between height(p<0.05) and weight(p<0.01) according to obesity degree among the four groups. 50.3% of the boys and 55.3% of the girls are regularly, and the main reason they didn't ate regularly, and the maim reason they didn't eat breakfast(78.4%) was due to lack of time. The frequency of snacks were 1-2 times a week(40.4%), fruits(40.4%) from market and supermarket(68.2%). According to the survey 84.6%, 77.45, 78.1%, 69.9%, 59.9% and 86.6% of subjects didn't eat meat, fish, soysauce, instant food, sugar and seaweed respectively. Seaweed, meat, and soysauce showed low preferences. 69.5% and 74.75 of the subjects drink milk and ate kimchi respectively. By analyzing eating habits according to the degree of obesity, the rate of skipping breakfast(p<0.01), and eating meat or fish(p<0.05) were high in the overweight and obese groups of girls. In the boys case, the rate of not eating food in sugar(p<0.05) was high in the obese group. Obese children need to correct their eating habit. This reasserts the importance of nutrition education in children though teachers, parents, and dietitions. The findings of this study may be applied to nutrition education to ensure better physical fitness for children.

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건강한 한국성인의 음료섭취패턴과 대사증후군의 연관성 연구 -2013~2015년 국민건강영양조사를 바탕으로- (Relation between Beverage Consumption Pattern and Metabolic Syndrome among Healthy Korean Adults)

  • 데니스 은주;강민지;한성림
    • 대한지역사회영양학회지
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    • 제22권5호
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    • pp.441-455
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    • 2017
  • Objectives: The purpose of this study is to describe beverage patterns among healthy Korean adults and investigate their association with prevalence and components of metabolic syndrome. Methods: Subjects consisted of 6,927 Korean adults, aged 19-64 years in the $6^{th}$ Korea National Health and Nutrition Examination Survey (KNHANES, 2013-2015). Beverages were regrouped into twelve groups based on food codes and beverage intake (g/day) was assessed by 24-hour recall. Factor analysis was used to obtain beverage patterns. Waist circumference and body mass index (BMI) were used as anthropometric data; fasting blood glucose, triglyceride, high density lipoprotein (HDL), and blood pressure were used as biochemical indicators. The odds ratio (OR) for prevalence of metabolic syndrome and components of metabolic syndrome was assessed using logistic regression analysis. Results: Three beverage patterns were identified using factor analysis: 1) carbonated soft drinks 2) coffee (without added sugar or powdered creamer), and 3) alcoholic beverages. Subjects with high scores for the carbonated soft drink and coffee without added sugar or powdered creamer patterns were younger and subjects with high scores for the alcoholic beverage pattern were older. There were significant differences in gender distribution in all three beverage patterns, with men more likely to have high scores for carbonated soft drink and alcoholic beverage patterns. On the other hand, women were more likely to have higher scores for coffee without added sugar or powdered creamer pattern. Within each pattern, there were significant differences in sociodemographic and lifestyle characteristics such as education, household income, frequency of eating out, and smoking status according to the quartile of pattern scores. Alcoholic beverages and carbonated soft drinks patterns were associated with an increased levels of metabolic syndrome components, but coffee without added sugar or powdered creamer was not associated with any of metabolic syndrome components in healthy Korean adults after adjusting for age, sex, education, BMI, weight management, household income, smoking status, frequency of eating out, and energy intake. Conclusions: Alcoholic beverages and carbonated soft drinks patterns are associated with increased levels of metabolic syndrome components while coffee without added sugar or powdered creamer pattern is not associated with any of metabolic syndrome components in healthy Korean adults.

타액선 상피성 종양 387례에 대한 연구 (Histopathological and Clinical Studies of the 387 Cases of Salivary Gland Epithelial Tumors)

  • 채성원;최건;최종상;송재준;정광윤;최종욱
    • 대한기관식도과학회지
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    • 제4권2호
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    • pp.211-218
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    • 1998
  • There have been few large scale surveys of salivary gland tumors, because the salivary gland tumors comprised less than 3 percent of all neoplasms of the head and neck. Also there is a problem that the incidences of specific types of tumors have the variation according to the geographic regions. ]'nother Korean reports about salivary gland tumor, they only treated about 100 cases only. Objectives : The purpose of this study is to identify the frequency and clinical characteristics of salivary gland tumors and to compare with other Korean reports. Materials and Methods : We had performed to analyze 387 cases of salivary gland tumors from 1983 to June 1997, were reviewed in histopathological and clinical aspects. The diagnoses of individual tumors were based on the World Health Organization classification. Tumors were analyzed according to the histologic type site, age and sex. Results : The majority (79.1%) of cases occurred in the major salivary glands and 20.9% in the minor. The parotid gland was the most frequent site with 52.4% and submandibular glands with 26.3%. Benign tumors were 79.3% of the tumors and malignant tmon were 20.7%. The most frequent tumor was pleomorphic adenoma occupied 63.8% of the total and frequency percent of histologic type of 98 malignant tumors showed 35.7% of mucoepidermoid carcinomas, 24.5% of adenoid cystic carcinomas. Overall gender with female predominance with 1 : 1.4 of male to female ratio. The average age of patients was 42.8 years. The most frequent chief complaint was a palpable mass. The duration of the symptom was shorter in the malignant salivary gland tumors (26.7 months) than in the benign salivary gland tumors (38.2 months). Conclusion : Comparing to the previous Korean reports, the present study confirms that the incidence of salivary gland tumor was lower in the parotid gland, and was higher in the submandibular and minor salivary glands.

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50세 이상 고소득층 성인 및 노인의 고혈압 관련 건강 및 영양 요인에 관한 연구 - 2005년 국민건강영양조사 결과에 근거하여 - (Health and Nutritional Factors Related to Hypertension of Subjects Aged Over 50 in High Income Class - Based on the 2005 Korea National Health and Nutrition Examination Survey -)

  • 안소현;손숙미;박진경
    • 대한영양사협회학술지
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    • 제15권3호
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    • pp.311-327
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    • 2009
  • This study was performed to determine the health and nutritional risk factors associated with hypertension in Koreans over the age of 50 in a high-income class (more than twice as much family income as the 2005 Korean minimum cost of living, 668,540 Won). A total of 505 subjects aged over 50 from the 2005 Korean National Health and Nutrition Examination Survey (KNHANES) were divided into two groups: A hypertension group (HG) (N=151, Systolic Blood Pressure ${\geq}$140 mmHg or Diastolic Blood Pressure ${\geq}$90 mmHg) and normal group (NG) (N=354). Subjects who took hypertension medicines or underwent diet therapy were excluded. In HG, mean daily alcohol intake and the amount of alcohol consumption per one occasion were significantly higher than in NG, respectively. A greater number of hypertension subjects answered that they drank alcohol to reduce stress as compared to normal subjects. HG also took fewer dietary supplements than NG. Mean body mass index (BMI), waist circumference, fasting blood sugar level, and 2 hour postprandial blood sugar following a glucose load were significantly higher in HG than in NG, respectively. Also, iron, thiamin, and niacin intakes and the consumption frequency of seaweeds were significantly lower in HG than in NG, respectively. Finally, obesity (BMI ${\geq}$25 $kg/m^2$), abdominal obesity (waist circumference ${\geq}$90 cm for males, ${\geq}$ 80 cm for females), high blood sugar level 2 hours after an oral glucose load (${\geq}$140~200 mg/dl), and hypertriglyceridemia (serum TG ${\geq}$200 mg/dl) were related to a significantly higher risk of hypertension in the subjects (odds ratio: 1.884~3.040). In conclusion, dietary factors such as higher alcohol consumption; lower intakes of iron, thiamin, and niacin; lower consumption frequency of seaweeds; and metabolic syndrome were associated with hypertension in the study subjects.

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한국인 성인 남녀에서 허리 둘레 기준 복부비만에 따른 영양섭취상태 평가: 2010-2012 국민건강영양조사 자료를 이용하여 (Evaluation of nutrient and food intake status, and dietary quality according to abdominal obesity based on waist circumference in Korean adults: Based on 2010-2012 Korean National Health and Nutrition Examination Survey)

  • 김명성;권대철;배윤정
    • Journal of Nutrition and Health
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    • 제47권6호
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    • pp.403-415
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    • 2014
  • 본 연구는 국민건강영양조사 데이터를 활용하여 우리나라 성인에서 성별 허리둘레를 기준으로 한 복부비만 여부에 따른 혈액지표, 생활습관, 식사섭취 상태 및 식사의 질을 분석한 결과, 남성과 여성 모두에서 허리둘레 기준 복부비만군의 경우 정상군에 비해 대사적 지표 (혈중 콜레스테롤, 중성지방, 혈당 및 혈압)가 모두 유의적으로 높게 나타났으며, 여성 허리둘레 기준 복부비만군에서 비타민 $B_2$, 칼슘, 인 및 칼륨 등 미량영양소 섭취의 질이 정상군에 비해 유의적으로 낮았고, 식품 섭취의 다양성을 의미하는 식품군 점수 및 총 식품점수도 비만군이 정상군에 비해 유의적으로 낮게 나타났다. 또한 여성의 경우 식품 섭취의 다양성 (총 식품점수)이 증가할수록 허리둘레 기준 복부비만 위험도가 유의적으로 낮게 나타난 의미 있는 결과를 도출하였다. 이와 같은 결과는 비만의 관리 및 예방을 위해 영양소의 과부족이 없고 미량영양소의 적절한 공급을 가능하게 하는 다양한 식품의 섭취를 권장할 수 있는 근거자료 및 영양교육의 기초자료로 활용할 수 있을 것으로 사료된다.

2012년~2013년 국민건강영양조사 자료를 이용한 중년 남성의 단백질섭취비와 섭취패턴에 따른 대사증후군 위험도 비교 (Metabolic Syndrome Risk by Intake Ratio and Intake Pattern of Proteins in Middle-aged Men Based on the 2012-2013 Korean National Health and Nutrition Examination Survey Data)

  • 장민경;허은실;이경혜
    • 대한지역사회영양학회지
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    • 제21권4호
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    • pp.366-377
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    • 2016
  • Objectives: The purpose of the study was to compare intake of energy nutrients, physical characteristics, and the prevalence of metabolic syndrome according to protein intake group. Methods: Subjects were 827 men aged 40-65 years. The results presented were based on data from the 2012-2013 National Health and Nutrition Examination Survey and analyzed using SPSS. The odds ratio (OR) of metabolic syndrome was assessed according to the protein intake group and intake pattern of protein-rich foods. Results: The mean of protein intake was $73.96{\pm}0.71g$. According to level of protein intake, four groups (deficient, normal, excess 1, excess 2) were created and their percentages were 8.3%, 39.6%, 37.1%, and 15.0% respectively. The mean of daily energy intake was $2,312.33{\pm}24.08kcal$. It was higher in excess group 2 than in the deficiency group (p < 0.001). Moreover, the intake of all energy nutrients increased significantly with protein intake group (p < 0.001). The main contribution to daily protein included mixed grains ($10.96{\pm}0.32g$), milled rice ($7.14{\pm}0.30g$), chicken ($3.50{\pm}0.21g$), and grilled pork belly ($3.04{\pm}0.16g$). With regard to physical characteristics, and blood pressure and blood test results, only body mass index increased significantly according to protein intake groups (p < 0.05). The prevalence of metabolic syndrome in subjects was 38.5%, and there was no significant correlation with protein intake group. The OR of metabolic syndrome increased with protein intake, and was higher 4.452 times in excess group 2 than in the normal group (p < 0.05). Conversely, the OR of metabolic syndrome according to the frequency of protein-rich food intake did not show a significant correlation. Conclusions: The results of this study can be used as significant supporting data to establish guidelines for protein intake in middle-aged men.