• Title/Summary/Keyword: Analysis of variances

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Assessment of Selenium Status in Adult Females According to Life Cycle (성인 여성의 생애주기별 셀레늄 영양상태에 대한 평가)

  • 이옥희;문종화;정용삼
    • Journal of Nutrition and Health
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    • v.36 no.5
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    • pp.491-499
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    • 2003
  • Selenium is a strong antioxidant trace mineral, scavenging free radicals. The prevalence of chronic degenerative diseases is increasing in Korean adults with increasing age. The increased cell damage from free radicals has been implicated in the etiology of these diseases, and evidence is accumulating that the low selenium status that comes with advanced aged is involved in the prevalence of age-associated diseases. However, little is known about the selenium status of Koreans, its age-related change and its relationship to dietary nutrient intake. In this study, the serum selenium levels of healthy adult females according to life cycle and its association with blood albumin levels and nutrient intake were examined. Serum selenium level was measured with the Huwo research reactor using the neutron activation analysis method (NAA). The overall proportion of women with selenium deficiency, serum selenium concentrations below 7.0 $\mu\textrm{g}$/dl, was 9.4%. The average serum selenium levels were 12.39 $\mu\textrm{g}$/dl, 9.45 $\mu\textrm{g}$/dl and 9.16 $\mu\textrm{g}$/dl in the young adult, middle-aged and elderly groups, respectively, showing a reduction of selenium status with advancing age. Selenium deficiency was seen only in the elderly group. Generally, serum selenium levels positively or negatively correlated with nutrient intake, but these association patterns differed depending on the age. The nutrients that showed positive correlations with selenium levels were proteins and phosphate in the young adult group (p < 0.05, p < 0.05), and total calcium, potassium and vegetable-origin calcium in the middle-aged group. Vitamin C and fiber were the negative correlated nutrients with serum selenium levels in the elderly group (p < 0.05, p < 0.05). Multiple stepwise regression analysis of the determining factors responsible for selenium status showed that age and serum albumin levels were important factors which explained up to 26.9% variances in serum selenium levels. The average selenium concentrations of Korean adult female subjects were above the deficiency levels in all three age groups. There was a tendency toward decreasing selenium levels as the age of the subjects increased. The factors with the strongest in-fluence on selenium status in healthy adult Korean females were age and serum protein status. (Korean J Nutrition 36(5): 491~499, 2003)

Analysis of simulation results using statistical models (통계모형을 이용하여 모의실험 결과 분석하기)

  • Kim, Ji-Hyun;Kim, Bongseong
    • The Korean Journal of Applied Statistics
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    • v.34 no.5
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    • pp.761-772
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    • 2021
  • Simulation results for the comparison of estimators of interest are usually reported in tables or plots. However, if the simulations are conducted under various conditions for many estimators, the comparison can be difficult to be made with tables or plots. Furthermore, for algorithms that take a long time to run, the number of iterations of the simulation is costly to to be increased. The analysis of simulation results using regression models allows us to compare the estimators more systematically and effectively. Since variances in performance measures may vary depending on the simulation conditions and estimators, the heteroscedasticity of the error term should be allowed in the regression model. And multiple comparisons should be made because multiple estimators should be compared simultaneously. We introduce background theories of heteroscedasticity and multiple comparisons in the context of analyzing simulation results. We also present a concrete example.

Stochastic Disaggregation and Aggregation of Localized Uncertainty in Pavement Deterioration Process (포장파손과정의 지역적 불확실성에 대한 확률적 분해와 조합)

  • Han, Daeseok
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.33 no.4
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    • pp.1651-1664
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    • 2013
  • Precise analysis on deterioration processes of road pavements is not so simple matter due to severe uncertainty originated from a lot of explanatory variables engaged in. For those reasons, most analytical models for pavement deterioration prediction have often preferred to probabilistic approaches than deterministic models. However, the general probabilistic approaches that treat overall characteristics of population or entire sample would not be suitable for providing detail or localized information on their changing process. Considering the aspects, this paper aimed to suggest a stochastic disaggregation method to analyze the localized deterioration speeds and its variances changed by time and condition states. In addition, life expectancies and their uncertainty were estimated by probabilistic algorithm using the disaggregated stochastic process. For an empirical study, pavement inspection data (crack) accumulated from 2003 to 2010 from Korean national highway network was applied. This study can contribute to securing reliability of life cycle cost analysis, which is one of the primary analyses in road asset management, with much advanced deterioration forecasting functions. In addition, it would be meaningful trials as fundamental research for preventive maintenance strategy that demands essential understanding on changing process of the deterioration speed of pavement.

A Study of college Women's view on Marriage According to Self-Actualization Degree -centering around seoul city- (여대생의 自我實現性에 따른 결혼관에 관한 연구-서울시를 중심으로-)

  • 정현아;서병숙
    • Journal of Families and Better Life
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    • v.3 no.1
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    • pp.94-106
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    • 1985
  • The purpose of this study is to apprehend college women's views on marriage in order to systematize the view theoretically, and to investigate the relationship between the self-actualization and their marriage perspective. Futhermore, it is my hope to provide some basic materials for making an desirable view on marriage. The measuring tools used for preparing this study are self-actualization test, which were designed originally by Shostrom and standardized to be suitable for Korean society by Kim Jae Ean and Lee Kwang Ja and a questionnaire about one's view on marriage. Statistical methods such as frequency, percentile, arithmetic mean, analysis of variances(X2 and F values)were used for data analysis. The results of this study are as follows; 1) It is revealed that more than half(59.7%) of the college women achieve normal or above normal degree of self-actualization. 2)It is revealed that most college women's attitude toward matrimony is positive and they have a large acquaintance with the opposite sex. Especially, they are eager to became employed after entering into matrimony. 3) It is revealed that the more satisfaction a college woman's mother feels about her own matrimony, the more positive attitude her daughter has toward marriage. some college women who do not want to have a child have a positive attitude toward divorce. This means that their matrimony depends upon their view of marriage. 4) It is revealed that the more self-actualization college women feel, the more negative attitude they have toward selecting their husband. 5)It is revealed that the less self-actualization college women feel, the more negative attitude they have toward having a large acquaintance with the opposite sex and they have a dependent attitude toward living with their parents 6) It is revealed that most college women want their husband to have higher academic career than hers regardless of her own self-actualization degree and they want have a job after entering into matrimony. It seems to be dispassionate reflection of contemporary thought.

A Study on Developing a Prediction Model of Patent Citation Counts (특허인용 예측모형 구축에 관한 연구)

  • Yoo, Jae-Bok;Chung, Young-Mee
    • Journal of the Korean Society for information Management
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    • v.27 no.4
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    • pp.239-258
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    • 2010
  • The purpose of this study is to develop a prediction model of patent citation counts based on major factors which affect patent citation. To this end, we performed multiple regression analysis between the patent citation counts and five explanatory variables such as the number of pages, the number of claims, the reference-average-citation rate, the strength of bibliographic coupling, and the document similarity proved as having 5% or more standardized variances($r^2$) with patent citation counts, with a test dataset of U.S. patents in five subject fields. As a result, our prediction models showed 58.3% to 89.6% predictability depending on subject fields and revealed the document similarity has the highest impact on citation counts among the five predictive variables in all the subject fields. The result of comparison between the predicted citation counts and the actual ones confirmed the usefulness of the citation prediction models built for each subject field.

Analysis on Electricity Consumption Characteristics of Apartments based on Architectural Planning Factors - foused on Households with a total area of 132~165㎡ in Seoul- (공동주택 건축계획요소에 따른 전기 에너지 소비특성 분석 - 서울지역의 40평형(132~165㎡)의 단위세대 전기에너지 사용량을 중심으로 -)

  • Park, So-Yun;Lee, Yun-Jae;Lee, Hyun-Soo
    • KIEAE Journal
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    • v.11 no.5
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    • pp.107-117
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    • 2011
  • This paper aims to analyze architectural planning factors that could contribute to reductions in electricity consumption in the household of apartments, to apply energy saving methods at the design phase. These six architectural planning factors were orientation, building type (flat, tower block), standard floor access type (corridor access type, stair case type, EV hall access type), household location (floor), household opening type (one side opening, right angle opening, two sides opening or three sides opening), and bay on the facade (one bay, two bays, three bays, four bays), and these were derived from literature review. Household electricity consumption data were gathered from 2168 households with a total area of 135~150$m^2$ of 6 apartment complexes over 1000 households in Seoul. The annual characteristics of electricity consumption according to architectural planning factors were analyzed. And, variances between groups with respect to the mean of summer, winter, and annual electricity consumption according to each architectural planning factors were analyzed using ANOVA and t-test. The results showed that an annual electric energy saving of over 1000kWh was facilitated by these planning factors. In addition, high energy efficiency architectural planning factors based on the analysis were as follows: southwest orientation, flat type, corridor access type and staircase type, household loation below the 20th floor, two sides opening and three sides opening, and 2 bays and 3 bays.

Competencies Evaluation of the Government Funded Research Institute's Employee : Focused on the K-institute case (정부출연 연구기관 종사자의 역량수준 진단 : K연구원 사례를 중심으로)

  • Yoo, Hye-Won;Hwang, In-A
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.13 no.10
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    • pp.4496-4505
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    • 2012
  • As the result of this study, total 27 core competencies are developed and categorized into four competence groups; common competence group, teamwork formation competence group, data-processing and analysis group and resource management and application competence group. The result of diagnosing of competency level, the required level of competencies were more higher than possessed level. This result supports that it is essential to raise the competency level of employees entirely through the education programs. The data analysis with two independent variances, rank and type of occupation, shows the significant difference between the required and current competency level in terms of ranks, staff, senior and principle. Therefore, it is necessary to provide a differentiated educational programs considering ranks.

Dynamic Response Analysis of Offshore Guyed Tower Subjected to Strong Earthquake under Moderate Random Waves (지진과 파랑하중을 동시에 받는 해양 가이드 타워의 비정상 동적 응답해석)

  • Ryu, Chung Son;Yun, Chung Bang
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.13 no.4
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    • pp.65-75
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    • 1993
  • Presented is a method for nonstationary response analysis of an offshore guyed tower subjected to strong earthquake motions under moderate random waves and current loadings. By taking the time varying envelope function and the auto-correlation function of the ground acceleration in terms of complex exponential functions, an analytical procedure is developed for computing time varying variances of the tower response. The stationary responses due to small random waves are obtained by using frequency domain method, and the results are combined with the nonstationary results due to earthquakes. Finally, the expected maximum responses are estimated. Through the example analyses, the nonstationary method developed in this study is verified, and the contributions of the earthquake, wave and current loadings to the total maximum response are investigated.

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The Impact of Reading on Self-Efficacy and Multicultural Acceptance: Using Multi-variate Latent Growth Model (독서가 자기효능감과 다문화수용성에 미치는 영향 분석 - 다변량 잠재성장모형을 적용하여 -)

  • Sungjae Park
    • Journal of Korean Library and Information Science Society
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    • v.53 no.4
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    • pp.293-318
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    • 2022
  • The purpose of this study is to analyze the impact of reading on self-efficacy and multicultural acceptance. The Korean Education and Employment Pannel II data were used for the analysis. Through analyzing the data with latent growth model, the growth trajectories for reading, self-efficacy, and multicultural acceptance were identified, and the relationship between three variances were analyzed using multi-variate latent growth model. As results, reading books, self-efficacy, and multicultural acceptance were decreased, as times go by. Next, the intercept of reading was postively related with self-efficacy and multicultural acceptance. Finally, self-efficacy mediated between the intercept of reading and the multicultural acceptance, and it's statistically significant.

Development of Profitability-forecasting Model for Apartment Reconstruction Projects using the Probabilistic Risk Analysis (확률적 위험도 분석 모형을 이용한 아파트 재건축사업의 수익성예측모델 개발)

  • Woo, Kwang-Min;Lee, Hak-Ki
    • Proceedings of the Korean Institute Of Construction Engineering and Management
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    • 2007.11a
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    • pp.54-59
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    • 2007
  • Recently, Apartment Reconstruction Projects are performing only with the basis of profitability without establishing either certain criteria or standard guideline. In addition, the profitability information contained in a disposal plan tends to be considered as a fixed value, and it is frequently changeable because reconstruction projects have such a long time to complete and many participants with respective interests. As mentioned above, the new approach needs to be developed which covers the limitation of the unvaried one. Consequently, this study focuses on the probability approach considering not only variances that affect the profit, but the relationship between profit and risk, and then is modeling. This study is anticipated to improve the reliability and accuracy of expected value as well as apply to the decision making criteria quantitively about potentially hidden risks in that projects.

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