• Title/Summary/Keyword: R statistic

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Reliability of Computerized Measurement of Laryngeal Erythema (후두 발적에 대한 컴퓨터 평가 시스템의 신뢰도 연구)

  • Moon, Byoung-Jae;Nam, Soon-Yuhl;Kim, Sang-Yoon;Choi, Seung-Ho
    • Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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    • v.16 no.1
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    • pp.19-22
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    • 2005
  • Background and Objectives : While considerable progress has been made in enhancing the quality of laryngoscopy and image processing, the evaluation of laryngeal erythema is still based on the clinician's judgement. The purpose of this study is to quantitatively measure the degree of erythema and to examine the relationship with clinical grading. Materials and Methods : Color images of larynx from 100 subjects were captured from video-documented examinations of laryngoscopy. The amount of erythema within the digitized larynx image was quantified using software developed and was compared with a grading system (0 to 3 scale) based on visual inspection by 4 experienced clinicians. The results were compared by deriving Kappa, Kendall and Spearman statistic. Results : There was high intra-observer(R=0.402-0.755) and inter-observer correlation (R=0.789). Among parameters, the red composite value had most remarkable agreement with clinical grading(R=0.827). Conclusion : The result suggest that the computer based analysis of laryngeal erythema can provide quantiative data on degree of erythema and the basis for further development of an expert system.

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Verification of Nonpoint Sources Runoff Estimation Model Equations for the Orchard Area (과수재배지 비점오염부하량 추정회귀식 비교 검증)

  • Kwon, Heon-Gak;Lee, Jae-Woon;Yi, Youn-Jeong;Cheon, Se-Uk
    • Journal of Korean Society on Water Environment
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    • v.30 no.1
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    • pp.8-15
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    • 2014
  • In this study, regression equation was analyzed to estimate non-point source (NPS) pollutant loads in orchard area. Many factors affecting the runoff of NPS pollutant as precipitation, storm duration time, antecedent dry weather period, total runoff density, average storm intensity and average runoff intensity were used as independent variables, NPS pollutant was used as a dependent variable to estimate multiple regression equation. Based on the real measurement data from 2008 to 2012, we performed correlation analysis among the environmental variables related to the rainfall NPS pollutant runoff. Significance test was confirmed that T-P ($R^2=0.89$) and BOD ($R^2=0.79$) showed the highest similarity with the estimated regression equations according to the NPS pollutant followed by SS and T-N with good similarity ($R^2$ >0.5). In the case of regression equation to estimate the NPS pollutant loads, regression equations of multiplied independent variables by exponential function and the logarithmic function model represented optimum with the experimented value.

Association Between Occupational Standing Time and Metabolic Syndrome in Korean Male Workers (근로자의 서서하는 작업시간과 대사증후군의 관련성)

  • Kim, Ki-Woong
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.24 no.3
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    • pp.383-392
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    • 2014
  • Purpose: In this study, we sought to understand the risk factor for chronic disease of workers by studying the association between occupational standing time and metabolic syndrome(MetS) in full-time 300 male workers. Materials: Data on age, life habit, work related information of the subjects were surveyed using self-reported questionnaire and interview. MetS was identified based on the report of Alberti et al.(2009). As for the data analysis, SPSS 19.0 was used to conduct the descriptive statistic, ANOVA, Pearson correlation coefficient and multiple logistic regression analysis. Results: Daily working hour affects on the lifting heavy objects, running and strenuous exercise(r=-0.137, p<0.01), and total physical function decreased with the increase in age(r=-0.145, p<0.01). Also, obese was significantly associated with genuflection and bend over(r=-0.110, p<0.05). On multiple logistic regression analysis for the diagnostic indices of MetS, occupational standing time were significantly associated with waist circumference(odds ratio=0.885, ${\beta}$ value=-0.122, 95% CI=0.797-0.983, p<0.05) and triglyceride (odds ratio=0.873, ${\beta}$ value=-0.136, 95% CI=0.800-0.953, p<0.01). Conclusions: These results suggest that the working posture may be important risk factor in pathogenesis and growing of MetS and cardiovascular disease.

A Comparative Study on the Accuracy of Important Statistical Prediction Techniques for Marketing Data (마케팅 데이터를 대상으로 중요 통계 예측 기법의 정확성에 대한 비교 연구)

  • Cho, Min-Ho
    • The Journal of the Korea institute of electronic communication sciences
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    • v.14 no.4
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    • pp.775-780
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    • 2019
  • Techniques for predicting the future can be categorized into statistics-based and deep-run-based techniques. Among them, statistic-based techniques are widely used because simple and highly accurate. However, working-level officials have difficulty using many analytical techniques correctly. In this study, we compared the accuracy of prediction by applying multinomial logistic regression, decision tree, random forest, support vector machine, and Bayesian inference to marketing related data. The same marketing data was used, and analysis was conducted by using R. The prediction results of various techniques reflecting the data characteristics of the marketing field will be a good reference for practitioners.

Spatial Point-pattern Analysis of a Population of Lodgepole Pine

  • Chhin, Sophan;Huang, Shongming
    • Journal of Forest and Environmental Science
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    • v.34 no.6
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    • pp.419-428
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    • 2018
  • Spatial point-patterns analyses were conducted to provide insight into the ecological process behind competition and mortality in two lodgepole pine (Pinus contorta Dougl. ex Loud. var. latifolia Engelm.) stands, one in the Lower Foothills, and the other in the Upper Foothills natural subregions in the boreal forest of Alberta, Canada. Spatial statistical tests were applied to live and dead trees and included Clark-Evans nearest neighbor statistic (R), nearest neighbor distribution function (G(r)), and a variant of Ripley's K function (L(r)). In both lodgepole pine plots, the results indicated that there was significant regularity in the spatial point-pattern of the surviving trees which indicates that competition has been a key driver of mortality and forest dynamics in these plots. Dead trees generally showed a clumping pattern in higher density patches. There were also significant bivariate relationships between live and dead trees, but the relationships differed by natural subregion. In the Lower Foothills plot there was significant attraction between live and dead tees which suggests mainly one-sided competition for light. In contrast, in the Upper Foothills plot, there was significant repulsion between live and dead trees which suggests two-sided competition for soil nutrients and soil moisture.

An Energy Technology R&D Investment Analysis of OECD Countries and Korea (한국과 OECD 국가의 에너지기술 R&D 투자규모 비교)

  • Min, Yun-Ji
    • International Commerce and Information Review
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    • v.16 no.4
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    • pp.363-384
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    • 2014
  • The adequate measurement of government expenditure efficiency for Energy Technology Development is a difficult empirical issue and the literature on it, particularly when it comes to aggregate and international data. Contribution in this study is threefold: first this study analyze the adequate measurement of government expenditure efficiency on Energy Technology sector of 24 OECD countries and korea. Second this study reconstruct efficiency composite indicators, named "Energy Technology Development Interest level indicator". Third this study assesses the efficiency of government expenditure for Energy Technology Development. The results can be summarized as follow: Korea's government expenditure efficiency for Energy Technology Development is highly ranked among 25 OECD countries based on Energy Technology Development R&D Budgets and Energy Technology Development R&D Budgets per thousand units of GDP indicators. However, Korea's ranking has fallen to 20th. The assessment suggests that government will be have to provide more government expenditure to enhance the efficiency on Energy.

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Statistical Assessment on the Heavy Metal Variation in the Soils around Abandoned Mine(Case Study for the Samgwang Mine) (폐광산지역 토양 중금속원소들에 대한 통계학적 환경오염 특성평가)

  • Cho, Il-Hyoung;Chun, Suk-Young;Chang, Soon-Woong
    • Journal of Environmental Science International
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    • v.16 no.12
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    • pp.1451-1462
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    • 2007
  • Heavy metal concentrations in the soil were investigated for the abandoned Samkwang metal mine, Cheongyang-Gun, Chungnam Province, Korea. The concentrations of heavy metal(As, Cd, Cu, Ni, Pb, Zn) were determined in mine soils collected at the abandoned mine sites to obtain a general classification and specification of the pollution in this highly polluted region. The results estimated with the normal test and basis statistic on the central tendency and variation showed that the distribution of heavy metal concentration had significantly different at the range of all locations. The range of spatial distribution on the relationship of heavy metal concentration and pH was $4.8{\sim}8.8$ and heavy metal concentration on the type of land use was highest in forest land, and also Ni and Zn in farm and rice field showed the high concentration. The distribution of heavy metal concentration on the depth of a soil showed that the metal concentrations in subsoil were higher than of those in surface soil, while the concentration of Cu and Ni had no significant difference on the depth of soil. Results from the correlation analysis using the data except the extreme and unusual data revel that Zn-Cd(r=0.867), Zn-As(r=0.797), Zn-Pb(r=0.764), Cu-Cd(r=0.673), Cu-As(r=0.614) and Zn-Ni(r=0.605) were the most important parameters in assessing variations of heavy metal in soil. To discriminate pattern differences and similarities among samples, principal factor analysis(PFA) and cluster analysis(CF) were performed using a correlation matrix. This study suggests that PFA and CF techniques are useful tools for identification of important heavy metal and parameters. This study presents the necessity and usefulness of multivariate statistical assessment of complex databases in order to get better information about the quality of soil and gives the basis information to clean up the abandoned mine sites.

The Availability of Gore-Tex® Tube as Nerve Conduit at the Peripheral Nerve Defect (말초신경 결손시 신경도관으로서 Gore-Tex® 도관의 유용성)

  • Lee, Ki Ho;Oh, Sang Ha;Lee, Seung Ryul;Kang, Nak Heon
    • Archives of Plastic Surgery
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    • v.32 no.5
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    • pp.613-618
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    • 2005
  • When a large peripheral nerve defect occurs, an autologous nerve graft is the most ideal method of recinstruction. But an autologous nerve graft has many limitations due to donor site morbidities. Many previous focused on finding the ideal nerve conduit. Among them, $Gore-Tex^{(R)}$ has several advantages over other conduits. It can be manipulated to a suitable size, does not collapse easily, and it is a semi- permeable material that contain pores. A round shaped nerve can be newly formed because of its smooth inner surface. The purpose of this study was to evaluate the availability of $Gore-Tex^{(R)}$ tube as a nerve conduit at the peripheral nerve defect in the rat sciatic nerve. The 10 mm nerve gap was made in each group. A $Gore-Tex^{(R)}$ tube filled with skeletal muscle was inserted and autologous nerve graft was harvested, respectively. In the experimental group, we placed a 0.5 mm thickness, $30{\mu}m$ pored, 1.8 mm in diameter and 14 mm length tube with skeletal muscle inserted inside. In the control group, the nerve gap was inserted with a rat sciatic nerve. We estimated the results electrophysiologically and histologically to 16 weeks postoperatively. Results in the nerve conduction velocity, total myelinated axon count, myelin sheath thickness and mean nerve fiber diameter, the experimental group was substantially lower than that of the control group, but the statistic difference was not significant (p<0.05). The morphology was very similar in both groups, microscopically. From the above results, We conclude that $Gore-Tex^{(R)}$ qualifies as an ideal nerve conduit. It is suggested that $Gore-Tex^{(R)}$ tube filled with skeletal muscle may, substitute for an autologous nerve graft.

The Relationship between Academic Stress and Cyberbullying Tendency among College Students: The Mediating Role of Self-Control (대학생의 학업스트레스와 사이버불링 경향성과의 관계: 자기통제력의 매개 효과)

  • Seol, Pil-Ran;Lee, Sung-Hee
    • The Journal of the Korea Contents Association
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    • v.21 no.11
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    • pp.576-585
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    • 2021
  • This study was a descriptive research study to examine the factors influencing cyberbullying tendency among college students. The data used in this study were collected from July 31 to August 13, 2020, from 396 students attending universities across South Korea. The collected data were analyzed using frequency, percentage, mean, standard deviation, Pearson correlation coefficients, PROCESS macro model 4, Bootstrap, Sobel test using IBM SPSS Statistics version 20.0 and PROCESS macro for SPSS. The results of this study are as follows. First, there was a significantly negative correlation between academic stress and self-control (r=-.246, p<.001). There was also a positive correlation between academic stress and cyberbullying tendency, but it was not significant (r=.096, p=.055). Second, the mediation effect of self-control is significant between academic stress and cyberbullying tendency (R2=.039, p<.001). Therefore, Academic stress and self-control should be considered in the development of cyberbullying prevention programs, and further research is also needed to verify the effectiveness of the cyberbullying prevention program based on this study.

A Study on Women's Specific Package Factors for Compact Vehicle (소형차에서의 여성 특화 패키지 인자 연구)

  • Nam, Jongyong;Lee, Yong;Kim, Taeyub;Park, Inseong;Lee, Hotaek
    • Transactions of the Korean Society of Automotive Engineers
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    • v.22 no.3
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    • pp.157-165
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    • 2014
  • To develop a compact vehicle for women, the most important areas are 'behavioral characteristics, life style and driving posture'. Static AM95%ile manikin is used for package guideline. Since women's characteristics and sitting position are different from men, however, the guideline cannot satisfy women drivers. Therefore, the goal of this study is to make the database with dynamic women's driving posture and behavioral characteristics at compact vehicle. Research process will be made as follows. Firstly, through the online/offline survey and statistic analysis, lifestyle and behavioral characteristics (discomfort elements) of women are extracted. Secondly, the author performs scenario test to acquire the discomfort value of driving situation and life style. 3D models of women's manikin and driving posture were created by CATIA HUMAN. The 3D models are used for the purpose of analyzing women's driving posture. Finally, with the ANOVA result and comparison between real driving posture and package guidelines, the author is able to suggest the main issue for women drivers.