• Title/Summary/Keyword: variance structure

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Fecal Microbiota Profiling of Holstein and Jersey, in South Korea : A Comparative Study (국내에서 사육되는 Holstein 젖소과 Jersey 젖소의 대변 미생물 분석 : 비교연구)

  • Gwangsu Ha;Ji-Won Seo;Hee Gun Yang;Se Won Park;Soo-Young Lee;Young Kyoung Park;RanHee Lee;Do-Youn Jeong;Hee-Jong Yang
    • Journal of Life Science
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    • v.33 no.7
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    • pp.565-573
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    • 2023
  • In light of the complex interactions between the host animal and its resident gut microbiomes, studies of these microbial communities as a means to improve cattle production are important. This study was conducted to analyze the intestinal microorganisms of Holstein (HT) and Jersey (JS), raised in Korea and to clarify the differences in microbial structures according to cattle species through next-generation sequencing. The alpha-diversity analysis revealed that most species richness and diversity indices were significantly higher in JS than in HT whereas phylogenetic diversity, which is the sum of taxonomic distances, is not significant. Microbial composition analysis showed that the intestinal microbial community structure of the two groups differed. In the both groups, a significant correlation was observed among the distribution of several microbes at the family level. In particular, a highly significant correlation (p<0.0001) among a variety of microbial distributions was found in JS. Beta-diversity analyis was to performed to statistically verify whether a difference exists in the intestinal microbial community structure of the two groups. Principal coordinate analysis and unweighted pair group method with arithmetic mean (UPGMA) clustering analysis showed separation between the HT and JS clusters. Meanwhile, permutational multivariate analysis of variance (PERMANOVA) revealed that their microbial structures are significantly different (p<0.0001). LEfSe biomarker analysis was performed to discover the differenc microbial features between the two groups. We found that several microbes, such as Firmicutes, Bacilli, Moraxellaceae and Pseudomonadales account for most of the difference in intestinal microbial community structure between the two groups.

Factor Analysis for Exploratory Research in the Distribution Science Field (유통과학분야에서 탐색적 연구를 위한 요인분석)

  • Yim, Myung-Seong
    • Journal of Distribution Science
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    • v.13 no.9
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    • pp.103-112
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    • 2015
  • Purpose - This paper aims to provide a step-by-step approach to factor analytic procedures, such as principal component analysis (PCA) and exploratory factor analysis (EFA), and to offer a guideline for factor analysis. Authors have argued that the results of PCA and EFA are substantially similar. Additionally, they assert that PCA is a more appropriate technique for factor analysis because PCA produces easily interpreted results that are likely to be the basis of better decisions. For these reasons, many researchers have used PCA as a technique instead of EFA. However, these techniques are clearly different. PCA should be used for data reduction. On the other hand, EFA has been tailored to identify any underlying factor structure, a set of measured variables that cause the manifest variables to covary. Thus, it is needed for a guideline and for procedures to use in factor analysis. To date, however, these two techniques have been indiscriminately misused. Research design, data, and methodology - This research conducted a literature review. For this, we summarized the meaningful and consistent arguments and drew up guidelines and suggested procedures for rigorous EFA. Results - PCA can be used instead of common factor analysis when all measured variables have high communality. However, common factor analysis is recommended for EFA. First, researchers should evaluate the sample size and check for sampling adequacy before conducting factor analysis. If these conditions are not satisfied, then the next steps cannot be followed. Sample size must be at least 100 with communality above 0.5 and a minimum subject to item ratio of at least 5:1, with a minimum of five items in EFA. Next, Bartlett's sphericity test and the Kaiser-Mayer-Olkin (KMO) measure should be assessed for sampling adequacy. The chi-square value for Bartlett's test should be significant. In addition, a KMO of more than 0.8 is recommended. The next step is to conduct a factor analysis. The analysis is composed of three stages. The first stage determines a rotation technique. Generally, ML or PAF will suggest to researchers the best results. Selection of one of the two techniques heavily hinges on data normality. ML requires normally distributed data; on the other hand, PAF does not. The second step is associated with determining the number of factors to retain in the EFA. The best way to determine the number of factors to retain is to apply three methods including eigenvalues greater than 1.0, the scree plot test, and the variance extracted. The last step is to select one of two rotation methods: orthogonal or oblique. If the research suggests some variables that are correlated to each other, then the oblique method should be selected for factor rotation because the method assumes all factors are correlated in the research. If not, the orthogonal method is possible for factor rotation. Conclusions - Recommendations are offered for the best factor analytic practice for empirical research.

CR Technology and Activation Plan for White Space Utilization (화이트 스페이스 활용을 위한 무선환경 인지 기술 및 활성화 방안)

  • Yoo, Sung-Jin;Kang, Kyu-Min;Jung, Hoiyoon;Park, SeungKeun
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.39B no.11
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    • pp.779-789
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    • 2014
  • Cognitive radio (CR) technology based on geo-location database access approach and/or wideband spectrum sensing approach is absolutely vital in order to recognize available frequency bands in white spaces (WSs), and efficiently utilize shared spectrums. This paper presents a new structure for the TVWS database access protocol implementation based on Internet Engineering Task Force (IETF) Protocol to Access WS database (PAWS). A wideband compressive spectrum sensing (WCSS) scheme using a modulated wideband converter is also proposed for the TVWS utilization. The developed database access protocol technology which is adopted in both the TV band device (TVBD) and the TVWS database operates well in the TV frequency bands. The proposed WCSS shows a stable performance in false alarm probability irrespective of noise variance estimation error as well as provides signal detection probabilities greater than 95%. This paper also investigates Federal Communications Commision (FCC) regulatory requirements of TVWS database as well as European Telecommunications Standards Institute (ETSI) policy related to TVWS database. A standardized protocol to achieve interoperability among multiple TVBDs and TVWS databases, which is currently prepared in the IETF, is discussed.

Comparative Study on the Job Satisfaction of Part-time Nurses and Internship Nurses (시간제 간호사 및 인턴간호사의 직무만족도에 관한 비교연구)

  • Choi, Sook-Ja
    • Research in Community and Public Health Nursing
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    • v.10 no.1
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    • pp.93-105
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    • 1999
  • Recently, Korean health care industry managers are paying more attention to customer oriented service, the rationalization of business administration, and quality control of service to adjust their business to outer environment since IMF bailout program. They are focusing on the cost reduction through remodeling the size and structure of man power, viz. labor flexibility. Nurses are not free from this juncture and contingent nurses are increasing fast. This article intends to verify the actual condition of two types of contingent nurses -part-time nurses and internship nurses-and to compare their job satisfaction to provide basic resource for efficient management of nurse man power. The concrete goals of this article are; Firstly, to verify the actual condition of their employment. Secondly, to compare their job satisfaction. And Thirdly, to the relation between employment condition and job satisfaction. To accomplish these research goals, a statistical survey was executed, in which 384 questionnaires - 66 for manager nurses, 318 for contingent nurses-were given to nurses working at 66 general hospitals-which have at least 100 beds-in Seoul. Among them, 121 questionnaires-of 28 general hospitals-were returned. Then, the data coded and submitted to mean, standard deviation, T-test, variance analysis (ANOVA), correlation analysis, multiple regression analysis with SAS program. The research results of the contingent nurses are followings: 1. Two types of contingent nurses shows similar age spans: they are mostly 21 - 30 years old and unmarried. But internship nurses have high level of educational career. Part - time nurses spread at general beds, out -patient part, intensive care part, operation part, etc, but internship nurses work mostly at general beds. 2. Two groups shows difference in actual employment condition: average employment career of part -time nurses is 7.0 months but internship nurses' is 2.0 months: average duty-on days per month of part - time nurses are 23.7 days but internship nurses' are 24.8 days. But there are little difference in average working time per day: 7.7 hours for part -time nurses and 0 hours for internship nurses. 3. The average wage per month for part -time nurses is 836,026 won but for internship nurses is 557,428 won-66.7% of part-time nurses'. Both groups are enjoying little additional pay. 4. Both groups are getting job not so much through advertisement of newspaper or hospitals as through acquainted person or college. 5. Both groups show very high level of job satisfaction: 3.2195 for part -time nurses and 3.2881 for internship nurses. But they show very low satisfaction on payment level compared with other categories and two groups show meaningful difference(P<.0001). 6. The multiple regression test reveals the factors related with job satisfaction: wage level, working part(OR or ICU), age, job career, and motive of contingent job-taking('because I can take care of family duties at the same time') influence positively: motive of contingent job-taking('because I can work regularly without alternation') influences negatively.

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The study of effects of Vandalism as a design variance on Users (사용자 측면에서의 디자인 변수로 작용하는 반달리즘 -Vandalism에 관한 연구)

  • 최성운;김경배
    • Archives of design research
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    • v.15 no.4
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    • pp.33-46
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    • 2002
  • The present times is rapidly growing and changing. As both an industry and a social legislation are running after a generality, relatively the number of people who are out of it is gradually increasing. Those people are getting skeptical about their positions as well as their existences, so that a social deviant phenomenon has been continuously arising by themselves in public and private area. It is the Vandalism . People are often exposed to this Vandalism which is occurring around their life. Accordingly this study analyzed cause-and-effect Vandalism. As a means of impediment against the progressing Vandalism in design process, the study as been developed by approaching to an ergonomics design, a simple shape design (minimalism), a semantic design, a re-useful design. As a result, it comes to the fact that the Vandalism from the view of design is caused by a lack of ergonomics and user-interface, a failure of simple structure, a complication of excessive functions. Furthermore, it comes to the conclusion that industrial design is playing an important role in the contribution of social development, to create a design obstructing the vandalism will bring development of sound society.

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A Study on Influence of Spatial Types Based on Public Library Spatial Characteristics (공공도서관 공간 특성에 따른 공간 유형 및 그 영향에 관한 연구)

  • Yook, Jihye;Kim, Giyeong
    • Journal of the Korean Society for information Management
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    • v.33 no.1
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    • pp.111-137
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    • 2016
  • The roles of public libraries have been diverse not only provision of information but also provision of cultural programs. According to this trend, the spatial composition of public libraries have been also changed to reflect the diverse roles. This study is conducted to explore the spatial characteristics in public libraries with two objectives: 1) to suggest spatial types in public libraries based on their physical characteristics, and 2) to explore the relationships between the spatial types and users' perception. To accomplish these objectives, we adopted observation and questionnaire survey as research methods. Consequently, three spatial types of public libraries are identified based on an investigation of several public libraries: divided, partially integrated, and integrated. Then, several statistical analyses, including one-way analysis of variance (ANOVA), are conducted with the questionnaire survey data. The results from the statical analyses show that there are significant differences in users' perceptions and behaviors between the spatial types. That is, the spatial type influences user's perceptions. This study is meaningful in terms of its first attempt to explore the relationships between spatial factors in libraries and users' perceptions. Based on this, it is suggested that libraries should consider their spatial structures for developing user's positive perception on the libraries.

Validity and Reliability Evaluation of Pregnancy Related Stress Scale (임부 스트레스 측정도구의 신뢰도 및 타당도 평가)

  • Lee, Hyejung;Seo, Minjeong
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.6
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    • pp.503-512
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    • 2017
  • The perceived stress of pregnant women is a potential contributor to adverse birth outcomes. Although the importance of the psychosocial well-being of pregnant women has been emphasized, there are fewreliable and valid instruments to measure the stress level of pregnant women in Korea. This study evaluated the psychometric properties of Ahn's pregnancy related stress scale (PSS) that was originally developed in 1984. Two hundred pregnant women completed the survey questionnaire, which was comprised of the PSS, depression scale, and demographic information. Principal component analysis and confirmatory factor analysis was used to test the construct validity. The concurrent validity was evaluated using the correlation with depression scores. Based on exploratory factor analysis and a consideration of conceptual meaning, a five-factor structure was extracted, explaining 57.25% of the variance: physical discomfort, fetus, parenting, spouse relationship, and housework. The goodness-of-fit indices showed an acceptable fit overall with the full model and acceptable internal consistency (Cronbach's alpha =.89). The concurrent validity was confirmed by a comparing with the depression score (r=.48, p <.001). The shortened PSS, as a valid and reliable scale, is recommended to be used to assess pregnancy-related stress and to develop stress managing interventions for pregnant women in clinical settings.

Modification of a Smoking Motivation Questionnaire for Chinese Medical Students

  • Jiang, Chao;Sun, Wen-Jie;Wan, Yan-Chun;Wei, Ming-Wei;Mu, Yong-Ping;Tarver, Siobhan L.;Gao, Yong-Qing;Hu, Tian;Xu, Chao;Gordon, James;Feng, Cindy Xin;Wen, Yu-Feng
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.6
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    • pp.2707-2711
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    • 2014
  • Introduction: Smoking prevalence among the medical students is high in China. Therefore, understanding the smoking motivations of medical students is crucial for smoking control, but currently there are no scales questionnaires customized for probing the smoking motivations of medical students. This aim of study was to test and modify a questionnaire for investigating smoking motivations among medical students. Methods: A cross-sectional survey was conducted among 1,125 medical students at Xuzhou Medical College in China in 2012.The model fit and validity was assessed by confirmatory factor analysis (CFA) and the reliability was tested by single-item reliability, composite reliability, and item-total correlation. Results: The prevalence of smoking was 9.84 % among study population. In the modified scales, the global fit indices identified a CFI value of 0.96, TLI was 0.96, and the RMSEA was 0.063. CFA supported the two dimensional structure of the instrument. The average variance extracted ranged from 0.45 to 0.62. All single-item reliability scores were greater than 0.20, and the composite reliability ranged from 0.74 to 0.91. Conclusion: Modified scales could be the preliminary instrument used in evaluating the smoking motivations of medical students. However, it should be further assessed using other forms and methods of validity and reliability, additional motivations of smoking, and the survey of other medical colleges in China.

Optimization of the Dual-layer LGP for Improving Luminance and Uniformity of Edge Type Back Light Unit (에지형 Back Light Unit의 휘도와 균일도 향상을 위한 복합도 광판 최적화)

  • Oh, Se-Won;Kim, Nam;Kim, Eun-Suk;An, June-Won
    • Korean Journal of Optics and Photonics
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    • v.21 no.6
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    • pp.247-253
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    • 2010
  • A dual-layer light guide plate (DLGP) was designed and a simulation was done to optimize the structure of the light guide plates used at backlight units while maintaining the luminance, uniformity and viewing angle by reducing the optical sheet. The characteristic of DLGP with prism pattern with curvature on the top surface is simulated and the luminance and uniformity are obtained. In order to improve the uniformity, the V groove prism pattern on the bottom surface was turned by an angle of $90^{\circ}$. In particular, we used the pitch calculation program to select the value of the ratio (Max : Min) between the pitch at the extreme outside and the pitch at the middle, the number of V groove lines and the variance at the bottom pattern of DLGP. After that, the optimum distance between V grooves was determined. For optimizing the DLGP, we examined the uniformity again by changing the number of pattern grooves on the bottom surface of DLGP. As a result of the simulation, we find that the BLU with DLGP has a uniformity of 90.6% and viewing angle $145^{\circ}$.

Development of Line Density Index for the Quantification of Oceanic Thermal Fronts (해양의 수온전선 정량화를 위한 선밀도 지수 개발)

  • Cho, Hyun-Woo;Kim, Kye-Hyun
    • Journal of the Korean Association of Geographic Information Studies
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    • v.9 no.2
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    • pp.227-238
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    • 2006
  • Line density index(LDI) was developed to quantify a densely isothermal line rate as standard index in the ocean environment. Theoretical background on the LDI development process restricting index range 0 to 100 was described. And validation test was done for the LDI application condition that total line length is not greater than 1/10 of unit area. NOAA SST(Sea Surface Temperature) data were used for the experimental application of LDI in the South Sea of Korea. Using GIS, $0.1^{\circ}C$ isothermal lines were linearized as vector data form SST raster data, and unit area were built as polygon data. For the LDI calculation, spatial overlapping(line in polygon) was implemented. To analyze the effect of unit area size for the LDI distribution, two cases of unit area size were designed and descriptive statistics was calculated including performing normality test. The results showed no change of LDI's essential characteristics such as mean and normality except for the range of value, variance and standard deviation. Accordingly, it was found that complex structure of thermal front and even smaller scale of front width than unit area size could influence on the LDI distribution. Also, correlation analysis performed between LDI and difference of temperature(${\Delta}T^{\circ}C$), and horizontal thermal gradient(${\Delta}T^{\circ}C/km$) on the front was obtained from linear regression model. This obtained value was compared with the results from previous researches. Newly developed LDI can be used to compare the thermal front regions changing spatio-temporally in the ocean environment using absolute index value. It is considered to be significant to analyze the relationship between thermal front and marine environment or front and marine organisms in a quantitative approach described in this study.

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