• Title/Summary/Keyword: Analysis of variances

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Breast cancer screening rates-related factors Korea women ever considering area environmental characteristics: The fourth Korea National Health and Nutrition Examination Survey(KNHANES IV) (지역 환경적 요인이 한국 여성의 유방암 조기검진 수검률에 미치는 영향 : 국민건강영양조사 제 4기를 중심으로)

  • Lee, Mi-Hwa;Kim, Sang-Hyun
    • Journal of Digital Convergence
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    • v.12 no.11
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    • pp.437-449
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    • 2014
  • In this study, we analyzed an effect of area-environmental factor on breast cancer screening rates using multi-level analysis. It was intended for the KNHANES-IV. Total subjects were 14338. Among them, 4143 subjects met the inclusion criteria. When we applied only empty Model, a variance of breast cancer screening rates was 0.061 in each region. When we applied Model with individual level variables, the variance was 0.034. However, when we applied both Model with individual level variables and Model with area level variables, the variance was 0.023. We drew applied only individual level variables parallel applied 3 regional variances which could explain variance of inspection of breast cancer up to 18.04% compared with applied only individual level variables. Area level variables could reduce a variance of region. This means besides individual level variables. The group can share a same thing and can effect to breast cancer screening rates. We need to discover factors which area level variables and suggest that make a standard for inspection of breast cancer.

Dynamic Analysis on Electricity Demands for the Steel Industry in Korea: Comparison between SMEs and Large Firms (우리나라 철강산업의 전력수요에 대한 동태 분석: 중소기업과 대기업 간 비교)

  • Li, Dmitriy;Bae, Jeong Hwan
    • Environmental and Resource Economics Review
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    • v.29 no.4
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    • pp.499-520
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    • 2020
  • Input ratio of electricity to other production inputs in the Korean manufacturing sector has been higher than for the other OECD countries. In addition, electricity prices in Korea has been relatively lower than the average of OECD countries. Moreover, electricity sector is responsible for most CO2 emissions in Korea as coal and natural gas account 41.9% and 26.8% of electricity production as of 2018. Therefore, it looks inevitable to raise the electricity tariff for the manufacturing sector in Korea, but there is a concern that increase in the electricity tariff might affect small and medium enterprises (SMEs) more than large firms. This study estimates electricity demand's price and output elasticities for large firms and SMEs in steel industry by employing a time varying parameter model (Kalman filter). The analysis shows that changes in output levels regardless of firms' size affect electricity demands more significantly than do changes in electricity prices. Second, large firms have higher variances for both price and output elasticities of electricity demand. Third, large firms have higher price elasticity but lower output elasticity of electricity demand relative to SMEs. Policy implications are suggested in association with how to reduce electricity demands in the energy-intensive industry.

A Review of Multivariate Analysis Studies Applied for Plant Morphology in Korea (국내 식물 형태 연구에 사용된 다변량분석 논문에 대한 재고)

  • Chang, Kae Sun;Oh, Hana;Kim, Hui;Lee, Heung Soo;Chang, Chin-Sung
    • Journal of Korean Society of Forest Science
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    • v.98 no.3
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    • pp.215-224
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    • 2009
  • A review was given of the role of traditional morphometrics in plant morphological studies using 54 published studies in three major journals and others in Korea, such as Journal of Korean Forestry Society, Korean Journal of Plant Taxonomy, Korean Journal of Breeding, Korean Journal of Apiculture, Journal of Life Science, and Korean Journal of Plant Resources from 1997 to 2008. The two most commonly used techniques of data analysis, cluster analysis (CA) and principal components analysis (PCA) with other statistical tests were discussed. The common problem of PCA is the underlying assumptions of methods, like random sampling and multivariate normal distribution of data. The procedure was intended mainly for continuous data and was not efficient for data which were not well summarized by variances or covariances. Likewise CA was most appropriate for categorical rather than continuous data. Also, the CA produced clusters whether or not natural groupings existed, and the results depended on both the similarity measure chosen and the algorithm used for clustering. An additional problems of the PCA and the CA arised with both qualitative and quantitative data with a limited number of variables and/or too few numbers of samples. Some of these problems may be avoided if a certain number of variables (more than 20 at least) and sufficient samples (40-50 at least) are considered for morphometric analyses, but we do not think that the methods are all mighty tools for data analysts. Instead, we do believe that reasonable applications combined with focus on objectives and limitations of each procedure would be a step forward.

Performance Prediction for an Adaptive Optics System Using Two Analysis Methods: Statistical Analysis and Computational Simulation (통계분석 및 전산모사 기법을 이용한 적응광학 시스템 성능 예측)

  • Han, Seok Gi;Joo, Ji Yong;Lee, Jun Ho;Park, Sang Yeong;Kim, Young Soo;Jung, Yong Suk;Jung, Do Hwan;Huh, Joon;Lee, Kihun
    • Korean Journal of Optics and Photonics
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    • v.33 no.4
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    • pp.167-176
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    • 2022
  • Adaptive optics (AO) systems compensate for atmospheric disturbance, especially phase distortion, by introducing counter-wavefront deformation calculated from real-time wavefront sensing or prediction. Because AO system implementations are time-consuming and costly, it is highly desirable to estimate the system's performance during the development of the AO system or its parts. Among several techniques, we mostly apply statistical analysis, computational simulation, and optical-bench tests. Statistical analysis estimates performance based on the sum of performance variances due to all design parameters, but ignores any correlation between them. Computational simulation models every part of an adaptive optics system, including atmospheric disturbance and a closed loop between wavefront sensor and deformable mirror, as close as possible to reality, but there are still some differences between simulation models and reality. The optical-bench test implements an almost identical AO system on an optical bench, to confirm the predictions of the previous methods. We are currently developing an AO system for a 1.6-m ground telescope using a deformable mirror that was recently developed in South Korea. This paper reports the results of the statistical analysis and computer simulation for the system's design and confirmation. For the analysis, we apply the Strehl ratio as the performance criterion, and the median seeing conditions at the Bohyun observatory in Korea. The statistical analysis predicts a Strehl ratio of 0.31. The simulation method similarly reports a slightly larger value of 0.32. During the study, the simulation method exhibits run-to-run variation due to the random nature of atmospheric disturbance, which converges when the simulation time is longer than 0.9 seconds, i.e., approximately 240 times the critical time constant of the applied atmospheric disturbance.

Influence of Amount of Pedigree Information and Parental Misidentification of Progeny on Estimates of Genetic Parameters in Jeju Race Horses (제주마 집단의 혈연 정보량과 정보 오류가 유전 모수 추정치에 미치는 영향)

  • Kim, Nam-Young;Lee, Sung-Soo;Yang, Young-Hoon
    • Journal of Embryo Transfer
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    • v.29 no.3
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    • pp.289-296
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    • 2014
  • The pedigree information and race records of 1,000 m finishing time of Jeju race horses at KRA were used to study the effect of amount of pedigree information and parental misidentification on the estimates of genetic parameters. The modified data sets were made at the range of 2.5 to 25% parental misidentifications or loss of parental information of individuals with an increment of 2.5 percent. For each incremental level, 20 randomly replicated data sets were obtained and analyzed by single-trait analysis with a DF-REML(AI) algorithm. As the rate of misidentification increased or the amount of pedigree information decreased, the estimates of fraction of additive genetics variance component gradually decreased almost linearly (p<0.05), while the estimated fractions of error variance and permanent environmental variance components gradually increased for the finishing time. Regression coefficients of the percentage amount of both parents' information loss and incorrect pedigree information on additive genetic variances were -0.079 and -0.114, respectively (p<0.01). The estimate of heritability decreased by 0.92% for one percent loss of both parents' information and 1.39% for one percent increase of both parental misidentifications of progeny (p<0.01). For the consideration of probable incorrect and missing parent information of progeny in this early population of Jeju horses, the estimates of additive genetic parameters would be biased downward about ten percent. This results indicate that the amount of pedigree information loss and misidentification of progeny would severely affect estimates of genetic parameters and would reduce genetic gains for selection in Jeju horse population.

A Study on the Socialization of Household Work and it's Related Variables -Focusing on the Employed and Unemployed Wives- (가사노동의 사회화 및 관련변인 고찰 -전문직 취업주부와 비취업주부를 중심으로-)

  • 이정우
    • Journal of the Korean Home Economics Association
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    • v.30 no.1
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    • pp.179-198
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    • 1992
  • The purspoe of this study is to identify the socialization level of household work of the employed and unemployed housewives and it's related variables in order to provide some fundamental information for the rational and effective performation of the household task. For the purpose of this study, 700 questionnaire were distributed to the employed and unemployed wives who lived in Seoul. The data were analyed by the Frequency distribution, Percentile, t-test, F-test, Duncan's Multiple Range Test, and Multiple Regression Analysis. The main results were as follows : (1) Socialization level of household work of the employed wives was a little below medium point. When the household work was devided into three subdomains, in the domain of food and shelter, the socialization level was far below medium point. In the domain of clothes, the socialization level was a little higher than medium point. Socialization level of household work of the unemployed wives far below average. When the household work was devided into three sudbomains, in the domain of food, clothes and shelter, the socialization level was far below average, too. Socialization level of household work was significantly different according to the employment. (2) Among the background veriables, family income, household work helper, and frequency of leisure activities have a significant influence on the socialization level of the employed wives. Duration of marriage, housewife's education level and house income have a important effect on the socialization level of the unemployed wives background. (3) Among the background variabels of household work, performing competence of household work is powerful effect on the socialization level of the employed wives. And as for the unemployed wives, performing competence of household task and recognition of the velue of household work are significant variables. (4) The psychological variable such as sex-role attitude gave no noticeable influence on the socialization level of employed and unemployed wives. (5) In conclusion, classifing the variances influencing on the socialization level of household work in a measure of respcetive effect, it appears to be performing competence of household task, frequency of leisure activities, house income, sex-role attitued and educational level in the order of their influences for the employed wives. And as for the unemployed wives, it seems to be house income, educational level, performing competence of household work and frequency of leisure activities. To the two sides, the rate of explanation is shown at 35%.

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Evaluation of Dry Matter Intake and Average Daily Gain Predicted by the Cornell Net Carbohydrate and Protein System in Crossbred Growing Bulls Kept in a Traditionally Confined Feeding System in China

  • Du, Jinping;Liang, Yi;Xin, Hangshu;Xue, Feng;Zhao, Jinshi;Ren, Liping;Meng, Qingxiang
    • Asian-Australasian Journal of Animal Sciences
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    • v.23 no.11
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    • pp.1445-1454
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    • 2010
  • Two separate animal trials were conducted to evaluate the coincidence of dry matter intake (DMI) and average daily gain (ADG) predicted by the Cornell Net Carbohydrate and Protein System (CNCPS) and observed actually in crossbred growing bulls kept in a traditionally confined feeding system in China. In Trial 1, 45 growing Simmental${\times}$Mongolia crossbred F1 bulls were assigned to three treatments (T1-3) with 15 animals in each treatment. Trial 2 was conducted with 60 Limousin${\times}$Fuzhou crossbred F2 bulls allocated to 4 treatments (t1-4). All of the animals were confined in individual stalls. DMI and ADG for each bull were measured as a mean of each treatment. All of the data about animals, environment, management and feeds required by the CNCPS model were collected, and model predictions were generated for animals on each treatment. Subsequently, model-predicted DMI and ADG were compared with the actually recorded results. In the three treatments in Trial 1, 93.3, 80.0 and 73.3% of points fell within the range from -0.4 to 0.4 kg/d for DMI mean bias; similarly, in the four treatments in Trial 2, about 86.7, 73.3, 73.3 and 80.0% of points fell within the same range. These results indicate that the CNCPS model can accurately predict DMI of crossbred bulls in the traditionally confined feeding system in China. There were no significant differences between predicted and observed ADG for T1 (p = 0.06) and T2 (p = 0.09) in Trial 1, and for t1 (p = 0.07), t2 (p = 0.14) and t4 (p = 0.83) in Trial 2. However, significant differences between predicted and observed ADG values were observed for T3 in Trial 1 (p<0.01) and for t3 in Trial 2 (p = 0.04). By regression analysis, a statistically different value of intercept from zero for the regression equation of DMI (p<0.01) or an identical value of ADG (p = 0.06) were obtained, whereas the slopes were significantly different (p<0.01) from unity for both DMI and ADG. Additionally, small root mean square error (RMSE) values were obtained for the unbiased estimator of the two variances (DMI and ADG). Thus, the present results indicated that the CNCPS model can give acceptable estimates of DMI and ADG of crossbred growing bulls kept in a traditionally confined feeding system in China.

Uncertainty Analysis of Wave Forces on Upright Sections of Composite Breakwaters (혼성제 직립벽에 작용하는 파력의 불확실성 해석)

  • Lee, Cheol-Eung
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.23 no.3
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    • pp.258-264
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    • 2011
  • A MCS technique is represented to stochastically analyze the uncertainties of wave forces exerted on the upright sections of composite breakwaters. A stochastical models for horizontal and uplift wave forces can be straightforwardly formulated as a function of the probabilistic characteristics of maximum wave height. Under the assumption of wave forces followed by extreme distribution, the behaviors of relative wave forces to Goda's wave forces are studied by the MCS technique. Double-truncated normal distribution is applied to take the effects of uncertainties of scale and shape parameters of extreme distribution into account properly. Averages and variances of relative wave forces are quantitatively calculated with respect to the exceedance probabilities of maximum design wave height. It is found that the averages of relative wave forces may be decreased consistently with the increases of the exceedance probabilities. In particular, the averages on uplift wave force are evaluated slightly larger than those on horizontal wave force, but the variations of coefficient of the former are adversely smaller than those of the latter. It means that the uncertainties of uplift wave forces are smaller than those of horizontal wave forces in the same condition of the exceedance probabilities. Therefore, the present results could be useful to the reliability based-design method that require the statistical properties about the uncertainties of wave forces.

A Study on the Clinical Characteristics of 4-Constitution Groups in 8-Constitution Medicine (8체질의학에서 목$\cdot$$\cdot$$\cdot$수 4체질군의 임상적 특징에 대한 연구)

  • Lee Sang-Beom;Choi Kyung-Mee;Park Young-Jae;Park Young-Bae
    • The Journal of Korean Medicine
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    • v.26 no.3 s.63
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    • pp.80-97
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    • 2005
  • Backgrounds : In recent years there has teen renewed interest in the importance of 8-constitution medicine as evidenced by growth of research in this field. Although diagnosis by 8-constitution depends on pulse types, it still is subjective and thus could be insignificant. Therefore, diagnosis based on objective characteristics is essential. Objectives : The purpose of this study was to find objective characteristics of the 4-constitution groups {木(Mok; hepatonia, cholecystonia), {土(To; pancreotonia, gastrotonia), {金(Gum; pulmotonia, colonotonia), {水(Soo; renotonia, vesicotonia)} in 8-constitution for further diagnosis and therapy. Also, some significant clinical tendencies of 4-constitution groups were studied. Methods : From Nov. 2001 to Apr. 2004, data were collected through a questionnaire given to 720 patients who were classified into one of 8 constitutions according to their pulse types and their responses to constitution-based acupuncture therapy. The questionnaire was composed of 80 items which were about personality, physical shape, habit, physiological and pathological symptoms, response to drugs, favorites and responses to various foods. The data were statistically analyzed by cross-tabulation and one-way analysis of variance, and SPSS V10.0.7PC was used. Results : The results are summarized as follows: 1) Among participants, proportions of hepatotonia, pancreotonia, and cholecystotonia were higher than those of vesicotonia, pulmotonia, colonotonia, renotonia, grstrotonia. 2) 52 items of 80 variances showed significant differences by gender, 3) 13 items were highly correlated with 4-constitution groups in males, and 26 items in fremales. 4) 22 items showed significant group differences among 4-constitution groups in males, and 41 items in females. Also, for each item 4-constitution groups were sorted according to their means, so that the constitutional tendencies were objectively figured out by personality, shape, habit, physiological and pathological symptoms, response to drugs, favorites and responses to foods. Conclusions : Most clinical characteristics of 4-constitution groups found in this study coincided with those from the previous ones in this fold. Thus, classifying patients into one of the 4-constitution groups based on significant objective characteristics is of great benefit to diagnosis and therapy. further study should be followed to improve proper therapy for each constitution.

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Development of An Instrument to Measure Hope for the Cancer Patients (암환자 간호를 위한 희망 측정도구 개발)

  • 김달숙;이소우
    • Journal of Korean Academy of Nursing
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    • v.28 no.2
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    • pp.441-456
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    • 1998
  • The purpose of this study was to develop a reliable and valid instrument to measure hope for cancer patients in Korea. This Hope Scale(Kim & Lee Hope Scale ; KLHS ) was developed based on not only critical universal attributes explaining both basic hope (generalized hope) and specific hope but also particular characteristics varing from culture and situation, which were revealed in a comprehensive review of the literature. Initially 60 items were generated from three sources : 36 items from the Q-sample used in the Kim's study, 1992, 21 representative items(statements) from the rest Q-population of the above study, 3 items related to the newly discovered category in the new qualitative study using 10 open ended question(death and dying) from the new qualitative study on the 20 cancer patients. At first 3 items were eliminated by the critique of the content validity experts, who were high experienced nurse, nursing professors. And then 4 items were eliminated in consideration of corrected item total correlation coefficiency, theoretical framework of this study. After that, 14 items were eliminated in comparing two or three items identified with the same meaning in each factor by this research team with factor loading and communality. This Hope Scale was finally constructed with 39 items. Psychometric evaluation was done on 492 adults(104 cancer patients, 388 adults who imagined who were cancer patients ranging from 18 to 76 years old. The results revealed high internal consistency Alpha coefficiency of .9351. Princial Component Factor Analysis with Varimax Rotation resulted in 8 factors with more than 1.0 of Eigenvalue. Referring to Eigenvalues, percent of variances(>60%), reproduced correlation matrix, and our theoretical framework, we decided the eight factors were the best1 solution to represent hope dimensions sufficiently. The eight factors were "confidence in possibility of cure", "sense of internal satisfaction", "being in communion", "meaning of life", "Korean hope perspectives", "belief in god", "self confidence", "self-worth". Among these factors, "confidence in possibility of cure", "sense of internal satisfaction", "Korean hope perspectives" were identified as different hope dimensions from those of Nowotny Hope Scale and Herth Hope Scale. There was significant negative correlation of r=-.4736 between this hope scale and Beck Hopelessness Scale (BHS), and significant positive correlation of r=.3685 between this hope scale and Life Orientation Test (LOT) which indicate convergent and discriminant validity. The range of hope scores was from 71 to 244, with a mean of 171.97(SD=28.16).

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