• Title/Summary/Keyword: 층화추정

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A Study on the Phonology of the Striped Rice Borer, Chilo suppressalis (Walker), in Relation to the Introduction of New Agricultural Practices (경종법에 변천에 따르는 이화명나방 발생상의 변동에 관한 연구)

  • Song Yoo Han;Choi Seung Yoon;Hyun Jai Sun
    • Korean journal of applied entomology
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    • v.21 no.1 s.50
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    • pp.38-48
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    • 1982
  • This study was conducted to investigate the changes in moth occurrence of striped rice barer, Chilo suppressalis (Walker), in relation to climatic factors, rice varieties, and cultural practices. The light trap data from 41 forecasting stations for 14 years from 1966 to 1979 were analyzed by means of the changes in the time and amount of borer occurrence in connection with the introduction of new rice varieties, the accumulated effective day-degree and its variation for completing one generation, and the climatic factors affecting the moth occurrence. The total number of moths caught by light traps in both spring and summer generations were considerably decreased with the wide cultivation of new rice varieties. In fact, the spring moths were remarkably decreased since the new varieties were introduced in 1972. The occurrence ratio of summer moths against the preceeding spring moths was higher in the middle region and middle southern mountainous area than the other regions. Its high ratio of regions was annually expanded from the middle region to the southern region. The $50\%$ emergence dates of both generations were later in the southeastern region than in the middle region. The ecological characteristics were clearly shown between the northern and southern region of Chupungryeong in terms of the occurrence of summer moths, the ratio of occurrence of summer moths to the preceeding spring moths, and $50\%$ emergence dates of the summer moths during the years of $1977\~1979$. The ratio of the summer moth occurrence to the preceeding generation was negatively correlated with the average temperature in lune and July, respectively, and the average precipitation in late June. The ratio of spring moth occurrence over the preceeding generation was positively correlated with the average temperature in September, October, November, and March, respectively, whereas it was negatively correlated with the average precipitation in early September and March, and the average humidity in early May. The effective day-degree for one generation was in the range from 600 to 900 DD at upper threshold $30^{\circ}C$ and lower threshold $10^{\circ}C$.

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Development of NQ-A, Nutrition Quotient for Korean Adolescents, to assess dietary quality and food behavior (청소년을 위한 영양지수 개발과 타당도 검증)

  • Kim, Hye-Young;Lee, Jung-Sug;Hwang, Ji-Yun;Kwon, Sehyug;Chung, Hae Rang;Kwak, Tong-Kyung;Kang, Myung-Hee;Choi, Young-Sun
    • Journal of Nutrition and Health
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    • v.50 no.2
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    • pp.142-157
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    • 2017
  • Purpose: The purpose of this study was to develop a nutrition quotient for adolescents (NQ-A) to assess overall dietary quality and food behavior of Korean adolescents. Methods: Development of the NQ-A was undertaken in three steps: item generation, item reduction, and validation. Candidate items of the NQ-A checklist were selected based on literature reviews, results of the fifth Korea National Health and Nutrition Examination Survey data, dietary guidelines for Korean adolescents, expert in-depth interviews, and national nutrition policies and recommendations. A total of 213 middle and high school students participated in a one-day dietary record survey and responded to 41 items in the food behavior checklist. Pearson's correlation coefficients between the responses to the checklist items along with nutritional status of the adolescents were calculated. Item reduction was performed, and 24 items were selected for the nation-wide survey. A total of 1,547 adolescents from 17 cities completed the checklist questionnaire. Exploratory factor and confirmatory factor analyses were performed to develop a final NQ-A model. Results: Nineteen items were finalized as the checklist items for the NQ-A. Checklist items were composed of five factors (balance, diversity, moderation, environment, and practice). The five-factor structure accounted for 47.2% of the total variance. Standardized path coefficients were used as weights of the items. The NQ-A and five-factor scores were calculated based on the obtained weights of the questionnaire items. Conclusion: Nutrition Quotient for adolescents (NQ-A) would be a useful instrument for evaluating dietary quality and food behavior of Korean adolescents. Further research on NQ-A is needed to reflect changes in adolescent's food behavior and environment.

A DESCRIPTIVE STUDY ON THE CONTRIBUTING FACTORS OF EARLY CHILDHOOD CARIES OF 5 YEARS CHILDREN IN KANGNUNG CITY (강릉시 5세 아동의 "조기 유아기 우식증" 관련 추정요인의 기술 역학적 연구)

  • Park, Jin-A;Ma, Deuk-Sang;Park, Deok-Young;Park, Ho-Won;Lee, Gwang-Su
    • Journal of the korean academy of Pediatric Dentistry
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    • v.29 no.2
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    • pp.226-236
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    • 2002
  • The purpose of this study was to get descriptive statistics of the contributing factors for early childhood caries and to predict the relationship of dietary, behavior factors and health status factors of the mother and child at pregnancy and after birth. 411 first caregivers of 5-year-old children in 12 kindergartens in Kangnung city were selected by stratified random cluster sampling. They were asked to fill out questionnaires and 364 of them responded. The obtained results were as follow: 1. Over the three-Fourth of children used nursing bottle or had breast feeding habit beyond the age of 1 year. 2. 8.7% of respondents didn't recognize the necessity of the preventive measures immediate after eruption of primary tooth, and only 35.1% replied that they had begun tooth cleaning. 3. Over 90% of children brush the teeth more than once per day. But over half (614%) of them brush their teeth without parents instruction. Sixty percent of children eat between the meals as often as 1-3 time(s) a day and the remainder at any times. 4. The first time of dental visit was for most children (87%) at over 3 years, recommending the earlier dental visit. Notwithstanding the rate of routine dental visit experience was relatively high(40.2%), implicating positive parents' attitude about oral health at Kangnung area. 5. The relationships between oral health state of the parents and the variables such as the timing of the first tooth cleaning, the frequency of brushing, the time of first dental visit, and the reason of first dental visit were not statistically significant. Together, there was no statistically significant difference between rural and urban area, private and public kindergarten, and boy and girl($x^2-test$, p>.05 or Fisher's exact test, p>.05).

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Development of NQ-E, Nutrition Quotient for Korean elderly: item selection and validation of factor structure (노인 대상 영양지수 개발 : 평가항목 선정과 구성 타당도 검증)

  • Chung, Min-Jae;Kwak, Tong-Kyung;Kim, Hye-Young;Kang, Myung-Hee;Lee, Jung-Sug;Chung, Hae Rang;Kwon, Sehyug;Hwang, Ji-Yun;Choi, Young-Sun
    • Journal of Nutrition and Health
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    • v.51 no.1
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    • pp.87-102
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    • 2018
  • Purpose: The purpose of this study was to develop a valid instrument for measuring the dietary quality and behaviors of Korean elderly. Methods: The development of the Nutrition Quotient for Elderly (NQ-E) was conducted in three steps: item generation, item reduction, and validation. The 41 items of the NQ-E checklist were derived from a systematic literature review, expert in-depth interviews, statistical analyses of the fifth Korean National Health and Nutrition Examination Survey data, and national nutrition policies and recommendations. Pearson's correlation was used to determine the level of agreement between the questionnaires and nutrient intake level, and 24 items were selected for a nationwide survey. A total of 1,000 nationwide elderly subjects completed the checklist questionnaire. The construct validity of the NQ-E was assessed using confirmatory factor analysis, LISREL. Results: The nineteen checklist items were used as final items for NQ-E. Checklist items were composed of four-factors: food behavior (6 items), balance (4 items), diversity (6 items), and moderation (3 items). The standardized path coefficients were used as the weights of the items. The NQ-E and four-factor scores were calculated according to the obtained weights of the questionnaire items. Conclusion: NQ-E would be a useful tool for assessing the food behavior and dietary quality of the elderly.

Development of nutrition quotient for elementary school children to evaluate dietary quality and eating behaviors (학령기 아동 대상 영양지수 개발과 타당도 검증)

  • Lee, Jung-Sug;Hwang, Ji-Yun;Kwon, Sehyug;Chung, Hae-Rang;Kwak, Tong-Kyung;Kang, Myung-Hee;Choi, Young-Sun;Kim, Hye-Young
    • Journal of Nutrition and Health
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    • v.53 no.6
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    • pp.629-647
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    • 2020
  • Purpose: This study was undertaken to develop a nutrition quotient for elementary school children (NQ-C) for evaluating the overall dietary quality and eating behaviors. Methods: The NQ-C was developed by implementing 3 stages: item generation, item reduction, and validation. Candidate food behavior checklist (FBC) items of the NQ-C were derived from systematic literature reviews, expert in-depth interviews, statistical analyses of the fifth Korean National Health and Nutrition Examination Survey data, and national nutrition policies and recommendations. For the pilot survey, 260 elementary school students (128 second graders and 132 fifth graders) completed self-administered questionnaires as well as 24-hour dietary intakes, with the help of their parents and survey team staff, if required. Based on the pilot survey results, expert reviews, and priorities of national nutrition policy and recommendations, checklist items were reduced from 41 to 24. A total of 20 items for NQ-C were finally selected from results generated from 1,144 nationwide samples surveyed. Construct validity of the NQ-C was assessed using the confirmatory factor analysis, LInear Structural RELations. Results: Analyses of the exploratory factors of NQ-C identified that 5 dimensions of diet (balance, diversity, moderation, practice and environment) accounted for 46.2% of the total variance. Standardized path coefficients were used as weights of the items. The NQ-C and 5-factor scores of the subjects were calculated using the obtained weights of the FBC items. Conclusion: Our data indicates that NQ-C is a useful and suitable instrument for assessing nutrition adequacy, dietary quality, and eating behaviors of Korean elementary school children.