• Imaging Science in Dentistry
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• v.52 no.3
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• pp.283-288
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• 2022

Purpose: This study was conducted to measure the radiation exposure and image quality of various cone-beam computed tomography (CBCT) machines under common clinical conditions and to analyze the correlation between them. Materials and Methods: Seven CBCT machines used frequently in clinical practice were selected. Because each machine has various sizes of fields of view (FOVs), 1 large FOV and 1 small FOV were selected for each machine. Radiation exposure was measured using a dose-area product (DAP) meter. The quality of the CBCT images was analyzed using 8 image quality parameters obtained using a dental volume tomography phantom. For statistical analysis, regression analysis using a generalized linear model was used. Results: Polymethyl-methacrylate (PMMA) noise and modulation transfer function (MTF) 10% showed statistically significant correlations with DAP values, presenting positive and negative correlations, respectively (P<0.05). Image quality parameters other than PMMA noise and MTF 10% did not demonstrate statistically significant correlations with DAP values. Conclusion: As radiation exposure and image quality are not proportionally related in clinically used equipment, it is necessary to evaluate and monitor radiation exposure and image quality separately.

• Wind and Structures
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• v.4 no.5
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• pp.413-440
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• 2001

This paper presents an extensive analysis of unsteady wind loading data on a 18 m long and 2 m high wall in a rural environment, with the wind at a range of angles to the wall normal. The data is firstly analyzed using standard statistical techniques (moments of probability distributions, auto- and cross-correlations, auto- and cross-spectra etc.). The analysis is taken further using a variety of less conventional methods - conditional sampling, proper orthogonal decomposition and wavelet analysis. It is shown that, even though the geometry is simple, the nature of the unsteady flow is surprisingly complex. The fluctuating pressures on the front face of the wall are to a great extent caused by the turbulent fluctuations in the upstream flow, and reflect the oncoming flow structures. The results further suggest that there are distinct structures in the oncoming flow with a variety of scales, and that the second order quasi-steady approach can predict the pressure fluctuations quite well. The fluctuating pressures on the rear face are also influenced by the fluctuations in the oncoming turbulence, but also by unsteady fluctuations due to wake unsteadiness. These fluctuations have a greater temporal and spatial coherence than on the front face and the quasi-steady method over-predicts the extent of these fluctuations. Finally the results are used to check some assumptions made in the current UK wind loading code of practice.

• Fashion & Textile Research Journal
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• v.17 no.5
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• pp.731-740
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• 2015

Mobile (smartphone) search engine marketing is increasingly important. Accordingly, the development of visual apparel search technology to obtain easier and faster access to visual information in the apparel field is urgently needed. This study helps establish a proper classifying system for an apparel search after an analysis of search techniques for apparel search applications and existing domestic and overseas apparel sites. An annotation technique is developed in accordance with visual attributes and apparel categories based on collected data obtained by web crawling and apparel images collecting. The categorical composition of apparel is divided into wearing, image and style. The web evaluation site traces the correlations of the apparel category and apparel factors as dependent upon visual attributes. An appraisal team of 10 individuals evaluated 2860 pieces of merchandise images. Data analysis consisted of correlations between apparel, sleeve length and apparel category (based on an average analysis), and correlation between fastener and apparel category (based on an average analysis). The study results can be considered as an epoch-making mobile apparel search system that can contribute to enhancing consumer convenience since it enables an effective search of type, price, distributor, and apparel image by a mobile photographing of the wearing state.

• Journal of the Korean housing association
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• v.19 no.2
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• pp.55-62
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• 2008

This study is researched to provide design guidelines of service facilities and programs that apartment residents want along with the increased quality of life. This study is signifiant because it sought effective methods to activate the com-munity culture through service facilities in apartment complexes and the design standard and planning direction for residents. The study results are as follows. In the result of the correlations analysis and multiple regression analysis for the importancy of service facilities in apartment complexes, the following orders were considered as important factor; man-ager office, open space, resident community facility, elderly people meeting and activity facility, walking paths, resident athletic facility, a children's playground, library, and rest areas in the complex. and result of the correlations analysis and multiple regression analysis is the following: service facilities whole importance (y) = 1.413$+0.262^*{\times}1$ (manager office importance)$+0.271^*{\times}2$ (open space importance) $+0.185^*{\times}3$ (resident community facility importance) $+0.136{\times}4$ (elderly people meeting and activity facility importance)$+0.036^*{\times}5$ (walking paths importance) $+0.031^*{\times}6$ (resident athletic facility importance) + $(-0.042)^*{\times}7$ (a children's playground importance) + $(-0.045)^*{\times}8$ (library importance) + $(-0.0097)^*{\times}9$ (rest areas importance).

• Journal of the Korean Society of Safety
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• v.31 no.1
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• pp.25-32
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• 2016

A sensitivity analysis of FDS(Fire Dynamics Simulator) results for the input uncertainty of heat release rate (Q) which might be the most influencing parameter to fire behaviors was performed. The calculated results were compared with experimental data obtained by the OECD/NEA PRISME project. The sensitivity of FDS results with the change in Q was also compared with the empirical correlations suggested in previous literature. As a result, the change in the specified Q led to the different dependence of major quantities such as temperature and species concentrations for the over- and under-ventilated fire conditions, respectively. It was also found that the sensitivity of major quantities to uncertain value of Q showed the significant difference in results obtained using the previous empirical correlations.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.8
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• pp.3503-3505
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• 2014

Background: Interleukin-33 (IL-33) has recently been implicated in tumor development. Methods: Data was obtained from PubMed, EMBASE, Clinical trial, Cochrane Library, Web of Science, CNKI and Wanfang databases. After quality assessment and data extraction, a meta-analysis was performed using Review Manager 5.2 software. Results: There were eight documents included in this meta-analysis. The results showed IL33 levels to be higher in tumor patients than that in health people, but no correlations tumor stage, metastasis and survival time of tumor patients were evident. Conclusion: IL33 may be useful as an alarm factor in tumor detection and prognosis.

• Nutrition Research and Practice
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• v.8 no.4
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• pp.432-438
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• 2014

BACKGROUND/OBJECTIVES: This research was conducted to develop a construct model regarding the dietary style, late night snacking choice attributes and health promotion behaviors of industrial workers. SUBJECTS/METHODS: The surveys were collected during the period between January and February 2013. A statistical analysis of 888 industrial workers was conducted using SPSS 12.0 for Windows and SEM (Structural Equation Model) using AMOS (Analysis of Moment Structure) 5.0 statistics package. RESULTS: The results of the correlations between all variables showed significant positive correlations (P < 0.05). Results of factors analysis on dietary styles were categorized into five factors and health promotion behaviors were categorized into four. The reliability of these findings was supported by a Cronbach's alpha coefficient of 0.6 and higher for all other factors. After obtaining the factors from processing an exploratory factor analysis and the end results supported the validity. In an attempt to study the late night snacking choice attributes in accordance to dietary styles and the health promotion behaviors of industrial workers, a structural equation model was constructed and analyzed. CONCLUSIONS: All tests proved the model satisfied the recommended levels of the goodness on fit index, and thus, the overall research model was proved to be appropriate.

• Nuclear Engineering and Technology
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• v.34 no.6
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• pp.596-609
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• 2002

Korea Electric Power Research Institute has developed the in-house safety analysis methodologies for non-LOCA(Loss Of Coolant Accident) events based on codes and methodologies of vendors and Electric Power Research Institute . According to the new methodologies, analyses of system responses and calculation of DNBR(Departure from Nucleate Boiling Ratio) during the transient have been carried out with RETRAN code and a sub-channel analysis code, respectively. However, it takes too much time to calculate DNBR for each case using the two codes to search for the limiting case from sensitivity study. To simplify the search for the limiting case, accordingly, RETRAN code has been modified to roughly calculate DNBR using hot channel modeling. The W-3 correlation is already included in RETRAN as one of the auxiliary DNBR models. However, WRB-1 and WRB-2 correlations required to analyze some Westinghouse type fuels are not considered in RETRAN DNBR models. In this paper, the RETRAN DNBR models using the correlations have been developed and the partial and complete loss of forced reactor coolant flow events have been analyzed for Yonggwang units 1 and 2 with the new methodologies to validate the models. The results of the analyses have been compared with those mentioned in the chapter 15 of the Final Safety Analysis Report.

• The Korean Journal of Community Living Science
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• v.26 no.2
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• pp.249-259
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• 2015

This study examines the effects of parental leadership and verbal control modes on preschool children's leadership. The sample included 202 children between the ages of 4 and 5 and their mothers, and data were collected using an index of parental leadership, an index of parental verbal control, and an inventory of preschool children's leadership. A statistical analysis was conducted using a t-test, a correlation analysis, and a multiple regression analysis. According to the results, there were significant differences in preschool children's leadership according to the child's age. According to a correlation analysis, parental leadership and verbal person-oriented control modes had significant positive correlations with preschool children's leadership, and imperative control and position-oriented control modes had negative correlations. In addition, parental leadership and verbal control modes were significant predictors of preschool children's leadership. In particular, parents' communication skill, relationship skill, group activity skill, person-oriented control mode, and position-oriented control mode were significant predictors of preschool children's leadership.

• Korean Journal of Human Ecology
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• v.10 no.1
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• pp.49-58
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• 2007

The purpose of this study was to investigate to relation between body satisfaction, attitude toward appearance and clothing of high school students. Method of posing a questionnaire is adopted to obtain stochastic data required for pertinent analysis. This is the investigation of which 356(male 169, female 187) high school students located in Choongnam and Junrabookdo province. In this statistical analysis, SPSS 11.5 for Windows Program was utilized to calculate percentage, mean and standard deviation, Factor analysis, Cluster analysis, t-test, One-way Anova, Duncan' multiple range, Pearson's correlation coefficient. The results of this research were as follows: The results of analysing the factors to the response body satisfaction, attitude toward appearance emerged three dimensions(Waist & hip, face, stature & figure part), three dimensions(needs value conformity toward appearance). Sex have significant effects on the body satisfaction, attitude toward appearance and clothing of high school students. Body satisfaction of high school students had an effects on attitude toward appearance and clothing attitude i. e. sexual attractiveness, fashion pursuit, modesty. Body satisfaction had negative correlations with attitude toward appearance and modesty of clothing. However, body satisfaction had positive correlations with sexual attractiveness and self-expression of clothing. As a conclusion, high school students' body satisfaction and attitude toward appearance constituted important characteristics which could affect clothing attitude directly.