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Estimation of Measurement Uncertainty in Vitamin C Analysis from Vegetable and Fruit Juice (야채음료 중 비타민 C 분석에 있어서의 측정불확도 추정)

  • Kim, Young-Jun;Kim, Hyeon-Wee
    • Korean Journal of Food Science and Technology
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    • v.35 no.6
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    • pp.1053-1059
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    • 2003
  • This study aimed to determine the amount of vitamin C from vegetable & fruit juice by high performance liquid chromatograhy (HPLC). Components for estimation of measurement uncertainty associated with the analysis of vitamin C, such as standard weight, purity, molecular weight, dilution of standard solution, calibration curve, recovery, and precision, were importantly applied. The estimation of uncertainty obtained with systematic and random error based on the GUM (Guide to the expression of uncertainty in measurement) and EURACHEM document with mathematical calculation and statistical analysis. The components, evaluated ty either Type A or Type B methods, were combined to produce an overall value of uncertainty known as the combined standard uncertainty. An expanded uncertainty was obtained by multiplying the combined standard uncertainty with a coverage factor (k) calculated from the effective degree of freedom. The content of vitamin C from vegetable and fruit juice was 27.53 mg/100g and the expanded uncertainty by multiplying by the coverage factor (k, 2.06) was 0.63 mg/100g at a 95% confidence level. It was concluded that the main sources were, in order of recovery and precision, weight and purity of the reference material, dilution of the standard solution, and calibration curve. Careful experiments on other higher uncertainties is further needed in addition to better personal proficiency in sample analysis in terms of accuracy and precision.

A Normality Test by Using the Simple Regression Analysis (단순(單純) 회귀분석(回歸分析)을 이용한 정규성검정(正規性檢定))

  • Lee, Chang-Ho;Han, Wang-Su
    • Journal of Korean Society for Quality Management
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    • v.13 no.1
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    • pp.77-83
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    • 1985
  • This paper deals with a normality test to determine whether the data are sampled from normal population or not. In this paper the property that the mean and variance are independently distributed only for the normal distribution is used as a basis for developing a new test using the simple regression analysis. Considering the redan and variance of a random sample as independent and dependent variables, if it has not the regression relationship we conclude that the data were sampled from the normal distribution. The Monte-Carlo power study shows that the new test using the simple regression analysis has good power property relative to 6 well-known test methods for 11 distributions.

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A Study on the proficiency test of pH measurements (pH 측정의 숙련도 시험에 대한 연구)

  • Lee, Hwashim;Kim, Myungsoo;Choi, Jongoh
    • Analytical Science and Technology
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    • v.14 no.3
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    • pp.230-237
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    • 2001
  • In general, the pH measurement follows calibration of glass electrode system using pH standard solution. When pH is measured at constant temperature, uncertainty factors are mainly related to the accuracy of pH standard solution and the accuracy and precision of glass electrode. Participants in this proficiency test were the volunteers trying to know the distribution of the measured pH values for the same sample and the sources of error through 1998 and 1999. The samples for proficiency test are phosphate salt standard solutions specially prepared in KRISS, of which pH values were 6.860, 7.415(at $25^{\circ}C$), and the stability test was performed for the same periods of proficiency test. The results of the proficiency test were plotted according to Youden plot, which shows whether the error is random or systematic. The results of Youden plot showed that the source of error was from the systematic effect of laboratories in each year. This shows that the source of error is the standard solutions used in laboratories.

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Differences in Dietary Life and Health related Factors According to Obesity in Poor Urban Peruvian Adolescents (페루 도시 빈민지역 청소년의 비만에 따른 식생활 및 건강요인의 차이)

  • Chung, Hye-Kyung;Lee, Hae-Young;Kim, Jin Ri;Nam, Eun Woo
    • Korean Journal of Community Nutrition
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    • v.23 no.4
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    • pp.302-318
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    • 2018
  • Objectives: This study examined the differences in dietary life and health related factors, such as drinking behavior, exercise and leisure activities, mental health, and subjective perception for oneself according to obesity in poor urban Peruvian adolescents. Methods: A total of 1,532 Peruvian adolescents were selected from six schools in poor regions using stratified random sampling. The subjects were classified into two groups based on their BMI: 'normal weight group (NW group=980)' or 'overweight and obese group (OWOB group=293)'. The differences in the general characteristics, dietary life, drinking behavior, physical activity and leisure, mental health and subjective perception of oneself in the two groups were compared. ${\chi}^2$ analysis and independent sample t-test were performed using the SPSS program ver. 24. Results: For the total and male students, the frequency of breakfast and dinner were significantly lower in the OWOB group than in the NW group (all p<0.001). For total and female students, the percentage of subjects who received nutrition education was significantly higher in the OWOB group than in the NW group (all p<0.05). For total students, the percentage of subject who exercised more than five days/week was lower in the OWOB group than in the NW group (p<0.05). For the total and female students, the subjective health status was worse in the OWOB group than in the NW group (all p<0.05). The subjective body image was significantly different between the OWOB group and NW group in the total, male and female subjects (all p<0.001). Conclusions: The frequency of meals and exercise, and the subjective perceptions of the health status and body image differed according to obesity in poor urban Peruvian adolescents. Therefore, a school-based intervention program focused on regular meal and exercise, and adequate subjective perceptions for health status and body image need to be developed to prevent adolescent obesity.

Expanding Health Education Plan For Improving Public Health (국민건강증진을 위한 보건교육확대방안에 관한 연구)

  • Yun, Gi-Seon;Park, Chung-Yeol
    • The Journal of the Korea Contents Association
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    • v.15 no.3
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    • pp.303-317
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    • 2015
  • Although the public health centers have been initiating health education recently, it is not extending as expected and the participation of the program is low. The reason is that the office workers have few opportunities to receive health education since there are few public health centers in relation to the population. Much time is required for travel and attendance of the classes. In order to solve this problem, the aim is to increase participation in health education, improve the overall public health awareness, expand the number of health education locations to reduce medical expenses, vitalize the lifelong educational health programs, and improve the national health insurance. In order to research about the health education expansion plan for public health improvement, a study focused on men and women above age 20 who need health education. The research sample was selected through random sampling that targeted people who participated in the health programs or the health education. The period of this survey was from September 1st to September 30th, 2014. A total of 509 participants completed the survey data for the actual analysis to propose the health education expansion plan for the public health improvement.

A Study on the Estimation of the Stock Density and Biomass of Perinereis aibuhitensis at the Tidal Zone in Sosan, Korea (서산 연안간석지에서 두토막눈썹참갯지렁이(청충), Perinereis aibuhitensis의 분포밀도와 현존자원량의 추정)

  • KIM Chong-Kawn;ZHANG Chang-Ik
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.24 no.4
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    • pp.229-236
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    • 1991
  • A study on the estimation of the stock density and biomass of Perinereis aibuhitensis in the tidal zone in Sosan, Chungchongnam-do, Korea was carried out from June to July 1988. A preliminary survey was conducted to determine the distribution pattern of the species and the optimum sample size for setting up the sampling design. The stock densities of the species by stratum and by subarea were estimated using the stratified random sampling method, based upon the results of preliminary survey. The differences in density between strata as well as among subareas were tested to decide whether they can be combined together for estimating the overall stock biomass or not. The results of the survey showed that p. aibuhitensis were randomly distributed(Poisson distribution) and the number of quadrats which satisfies a reasonable level of precision was determined to be five by stratum. The densities between strata were not significantly different, while densities among subareas were different. Subarea C showed the highest density with the mean of $53.9g/m^2$ and followed by subarea B. The density of subarea A was the lowest with the mean of $18.2g/m^2$. The overall mean density from the study area was $32.4g/m^2$ with the coefficient of variance(CV) of $6.8\%$ The overall stock biomass was estimated to be 147.5mt in this area.

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Marriage in Korea I. Evidence of Changing Attitudes and Practice

  • Kim, Mo-Im;Harper, Paul A.;Rider, Rowland V.;Yang, Jae-Mo
    • Clinical and Experimental Reproductive Medicine
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    • v.2 no.2
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    • pp.13-26
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    • 1975
  • Seven aspects of attitude toward marriage in Korea are examined to better understand present and future marriage patterns. Also, various facets of current marriage practice are compared with attitudes. The study comprises three groups of roughly 600 women each, selected by random sampling from a rural, an urban, and a semi-urban area. A carefully designed and pretested questionnaire was checked for reliability by a reinterview in a 15% subsample. The great majority of Korean women support traditional attitudes that one must or should marry. The small group who recommend that one should not marry are mostly the very young or the never married, whose attitudes still may change. However, there are important and probably predictive shifts in favor of more individual decision, especially among the better educated, the young, and the more urban. Traditional reasons for marriage such as "custom" and procreation are ranked first by a majority, but there is a large shift to more contemporary or liberal desire for companionship and love, also primarily among the better educated, the urban, the young, and the never married. The traditional attitude that parents should have the sole or major role in mate selection is still held by a bare majority; the educated, urban, young, and never married are more liberal. Only 6% opt for each of the two extremes: That the parent alone or the respondent alone should decide. The remainder prefer one of the two middle-of-the-road positions where parent and child together decide. The proportions of respondents who classed specified criteria as moat important for selecting a husband, arranging the criteria in order from traditional to contemporary were: Lineage, etc., 23%; personal attributes, 40%; health and education, 27%; and love, 10%. The changing attitudes are suggested by the fact that love was ranked first by only 3% of the poorly educated rural poulation versus 23% of urban college level and 31% of the urban never married. There has been a substantial rise in the ideal age of marriage over the past twelve or more years, but there also is evidence that the ideal age is at or near a ceiling. Knowledge about legal age of marriage is minimal; the implications of this for proposed legislation are discussed. Three-fifthes to four-fifths of all respondents married husbands of the same religious, residential, and economic backgrounds as themselves. Almost all of them married men of the same or higher educational level. These evidences of traditional influences in mate selection are contrasted with the low priority given some of those items in earlier questions on reasons for marriage and criterion for selecting husband. Contrary to the expressed attitudes as to who should select the husband, we find that marriages of the study sample were stated to be arranged by parents alone in 62%; and in another 23%, the parents made the decision but asked the respondent's views. Such arrangements were most frequent among the rural, the less educated, and the older respondents and less common in the urban and more educated. The implications of these and related findings are discussed.

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Service Quality beyond Access: A Multilevel Analysis of Neonatal, Infant, and Under-Five Child Mortality Using the Indian Demographic and Health Survey 2015~2016

  • Kim, Rockli;Choi, Narshil;Subramanian, S.V.;Oh, Juhwan
    • Perspectives in Nursing Science
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    • v.15 no.2
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    • pp.49-69
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    • 2018
  • Purpose: The purpose of this study was to derive contextual indicators of medical provider quality and assess their relative importance along with the individual utilization of antenatal care (ANC) and institutional births with a skilled birth attendant (SBA) in India using a multilevel framework. Methods: The 2015~2016 Demographic and Health Survey (DHS) from India was used to assess the outcomes of neonatal, infant, and under-five child mortality. The final analytic sample included 182,980 children across 28,283 communities, 640 districts, and 36 states and union territories. The contextual indicators of medical provider quality for districts and states were derived from the individual-level number of ANC visits (<4 or ${\geq}4$) and institutional delivery with SBA. A series of random effects logistic regression models were estimated with a stepwise addition of predictor variables. Results: About half of the mothers (47.3%) had attended ${\geq}4$ ANC visits and 75.8% delivered in institutional settings with SBAs. Based on ANC visits, 276~281 districts (43.1~43.9%) and 13~16 states (36.5~44.4%) were classified as "low" quality areas, whereas 268~285 districts (41.9~44.5%) and 8~9 states (22.2~25.0%) were classified as "low" quality areas based on institutional delivery with SBAs. Conditional on a comprehensive set of covariates, the individual use of both ANC and SBA were significantly associated with all mortality outcomes (OR: 1.17, 95% CI: 1.08, 1.26, and OR: 1.10, 95% CI: 1.02, 1.19, respectively, for under-five child mortality) and remained robust even after adjusting for contextual indicators of medical provider quality. Districts and states with low quality were associated with 57~61% and 27~43% higher odds of under-five child mortality, respectively. Conclusion: When simultaneously considered, district- and state-level provider quality mattered more than individual access to care for all mortality outcomes in India. Further investigations are needed to assess the importance of improving the quality of health service delivery at higher levels to prevent unnecessary child deaths in developing countries.

Effects of Process Variables on the Microstructure and Gas Sensing Characteristics of Magnetron Sputtered $\textrm{SnO}_2$Thin Films (마그네트론 스퍼터링 증착 조건에 따른 $\textrm{SnO}_2$ 박막의 미세구조와 가스검지특성 변화)

  • Kim, Jong-Min;Moon, Jong-Ha;Lee, Byung-Teak
    • Korean Journal of Materials Research
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    • v.9 no.11
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    • pp.1083-1087
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    • 1999
  • Microstructures and the gas-sensing characteristics of the $\textrm{SnO}_2$ thin films were studied, which were deposited at various conditions (rf power, sample temperature, $\textrm{O}_2$/Ar ratio) by the rf magnetron sputtering. As a result, six typical microstructures were derived, such as amorphous(A), amorphous mixed with polycrystalline grains (A+P), polycrystalline with random crystalographic orientation (P), fine columnar (FC), coarse columnar (CC) and Zone T (T) with dense fiberous structure. Typically, A, A+ P, and P structures were formed when no $\textrm{O}_2$ was added to the sputter gas, whereas FC, CC, and T structures were obtained when $\textrm{O}_2$ was added. The A structure formed at low rf power and low temperature, the A+P at high rf power and low temperature, and the P at high rf power and high temperature. The FC structure was obtained at low rf power and low temperature. the CC at low rf power and high temperature, and the T at high rf power and low temperature. Results of the gas-sensing test of the sensor chips fabricated from the typical films indicated that the fine columnar microstructure shows the highest sensitivity both at $300^{\circ}C$ and $400^{\circ}C$. It was proposed that this is due to the high specific surface area of the micro-columns.

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An Overview for Molecular Markers in Plants (식물에서 분자 마커의 동향)

  • Huh, Man Kyu
    • Journal of Life Science
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    • v.25 no.7
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    • pp.839-848
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    • 2015
  • A molecular marker is a molecule contained within a sample taken from an organism or other matter. The development of molecular techniques for genetic analysis has led to a great contribution to our knowledge of plant genetics and our understanding of the structure and behavior of various genomes in plants. Recently, functional molecular markers have been developed to detect the presence of major genes from the analysis of pedigreed data in absence of molecular information. DNA markers have developed into many systems based on different polymorphism-detecting techniques or methods such as RFLP, AFLP, RAPD, SSR, SNP, etc. A new class of very useful DNA markers called genic molecular markers utilizing the ever-increasing archives of gene sequence information being accumulated under the EST sequencing projects on a large number of plant species. Functional markers are derived from polymorphic sequences, and are more likely to be involved in phenotypic trait variation. Based on this conceptual framework, the marker systems discussed below are all (gene)-targeted markers, which have the potential to become functional. These markers being part of the cDNA/EST-sequences, are expected to represent the functional component of the genome i.e., gene(s), in contrast to all other random DNA based markers that are developed/generated from the anonymous genomic DNA sequences/domains irrespective of their genic content/information. Especially I sited Poczai et al’ reviews, advances in plant gene-targeted and functional markers. Their reviews may be some useful information to study molecular markers in plants.