• Title/Summary/Keyword: random procedure

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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.

A Study on Body Image of Women Who Participate in Physical Exercise (스포츠 센터 운동 참여에 따른 여성의 신체이미지에 관한 연구)

  • Kang, Byeol-Nim
    • Proceedings of the Korea Contents Association Conference
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    • 2006.11a
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    • pp.145-148
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    • 2006
  • This study aimed at preventing women from suffering from health problems and stress due to excessive lookism and encouraging them to participate in sports activities to form desirable body image and eventually to live a healthy and sound life. To achieve this goal, this study formed a population with members of sports centers located in Seoul and Daejeon areas as of 2006 and made a sample of 450 participants in physical exercise at a sports center through stratified cluster random sampling and that of 450 non-participants through a survey with mothers and sisters of those students from elementary and secondary schools within the areas for sampling the participants' group, thereby analyzing the data on a total of 900 persons. A questionnaire was used as a tool to collect data; a reliability test presented weight-, health-, and figure-related factors as a=.807, a=.819, and a=.784, respectively. This study used such statistical analysis methods as t-test, One-way ANOVA, and the Analysis of Covariance to analyze data. This study produced the following conclusions through these research methods and procedure. Pticipation in physical exercise has a positive effect on body image. Pticipation in physical exercise at a sports center show higher satisfaction with body image than non-participats.

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Analysis of Massive Transfusion Blood Product Use in a Tertiary Care Hospital (일개 3차 의료기관의 대량수혈 혈액 사용 분석)

  • Lim, Young Ae;Jung, Kyoungwon;Lee, John Cook-Jong
    • The Korean Journal of Blood Transfusion
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    • v.29 no.3
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    • pp.253-261
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    • 2018
  • Background: A massive blood transfusion (MT) requires significant efforts by the Blood Bank. This study examined blood product use in MT and emergency O Rh Positive red cells (O RBCs) available directly for emergency patients from the Trauma Center in Ajou University Hospital. Methods: MT was defined as a transfusion of 10 or more RBCs within 24 hours. The extracted data for the total RBCs, fresh frozen plasma (FFP), platelets (PLTs, single donor platelets (SDP) and random platelet concentrates (PC)) issued from Blood Bank between March 2016 and November 2017 from Hospital Information System were reviewed. SDP was considered equivalent to 6 units of PC. Results: A total of 345 MTs, and 6233/53268 (11.7%) RBCs, 4717/19376 (24.3%) FFP, and 4473/94166 (4.8%) PLTs were used in MT (P<0.001). For the RBC products in MT and non-MT transfusions, 28.0% and 34.1% were group A; 27.1% and 26.0% were group B; 37.3% and 29.7% were group O, and 7.5% and 10.2% were group AB (P<0.001). The ratios of RBC:FFP:PLT use were 1:0.76:0.72 in MT and 1:0.31:1.91 in non-MT (P<0.001). A total of 461 O RBCs were used in 36.2% (125/345) of MT cases and the number of O RBCs transfused per patient ranged from 1 to 18. Conclusion: RBCs with the O blood group are most used for MT. Ongoing education of clinicians to minimize the overuse of emergency O RBCs in MT is required. A procedure to have thawed plasma readily available in MT appears to be of importance because FFP was used frequently in MT.