• Communications for Statistical Applications and Methods
• /
• v.24 no.3
• /
• pp.271-290
• /
• 2017

We study a bivariate response regression model with arbitrary marginal distributions and joint distributions using Frank and Clayton's families of copulas. The proposed model is used for fitting dependent bivariate data with explanatory variables using the log-odd log-logistic Weibull distribution. We consider likelihood inferential procedures based on constrained parameters. For different parameter settings and sample sizes, various simulation studies are performed and compared to the performance of the bivariate odd-log-logistic-Weibull regression model. Sensitivity analysis methods (such as local and total influence) are investigated under three perturbation schemes. The methodology is illustrated in a study to assess changes on schoolchildren's oral health-related quality of life (OHRQoL) in a follow-up exam after three years and to evaluate the impact of caries incidence on the OHRQoL of adolescents.

• The Journal of Advanced Prosthodontics
• /
• v.5 no.4
• /
• pp.452-456
• /
• 2013

PURPOSE. The aim of this study was to evaluate the repeatability of the digitizing of silicon rubber impressions of abutment teeth by using a white light scanner and compare differences in repeatability between different abutment teeth types. MATERIALS AND METHODS. Silicon rubber impressions of a canine, premolar, and molar tooth were each digitized 8 times using a white light scanner, and 3D surface models were created using the point clouds. The size of any discrepancy between each model and the corresponding reference tooth were measured, and the distribution of these values was analyzed by an inspection software (PowerInspect 2012, Delcamplc., Birmingham, UK). Absolute values of discrepancies were analyzed by the Kruskal-Wallis test and multiple comparisons (${\alpha}$=.05). RESULTS. The discrepancy between the impressions for the canine, premolar, and molar teeth were $6.3{\mu}m$ (95% confidence interval [CI], 5.4-7.2), $6.4{\mu}m$ (95% CI, 5.3-7.6), and $8.9{\mu}m$ (95% CI, 8.2-9.5), respectively. The discrepancy of the molar tooth impression was significantly higher than that of other tooth types. The largest variation (as mean [SD]) in discrepancies was seen in the premolar tooth impression scans: $26.7{\mu}m$ (95% CI, 19.7-33.8); followed by canine and molar teeth impressions, $16.3{\mu}m$ (95% CI, 15.3- 17.3), and $14.0{\mu}m$ (95% CI, 12.3-15.7), respectively. CONCLUSION. The repeatability of the digitizing abutment teeth's silicon rubber impressions by using a white light scanner was improved compared to that with a laser scanner, showing only a low mean discrepancy between $6.3{\mu}m$ and $8.9{\mu}m$, which was in an clinically acceptable range. Premolar impression with a long and narrow shape showed a significantly larger discrepancy than canine and molar impressions. Further work is needed to increase the digitizing performance of the white light scanner for deep and slender impressions.

• Proceedings of the Korean Environmental Health Society Conference
• /
• 2005.06a
• /
• pp.381-385
• /
• 2005

Characterization of particle behavior is becoming more important in performance evaluation of water treatment system as well as in operation of the system because conventional parameter, turbidity has lack of explaining ability on small sized microorganisms such like Cryptosporidium etc. Accordingly, particle counter has been introduced in evaluation and operation of the treatment system. However researches on the relationship between turbidity, particle count and/or different sand/anthracite sizes have not been concurrent. Therefore in this study, the relationship was investigated to improve performance evaluation of sand filter so as to help choosing sand/anthracite effective size as a design parameter of water treatment facility. According to the results, too small or too large effective size media filter reached to turbidity limit(0.1 NTU)earlier. However, because shallow sand layer may cause early breakthrough, the depth of sand layer should be provided enough in order to compromise water quality and productivity.

• Proceedings of the Korean Environmental Health Society Conference
• /
• 2005.06a
• /
• pp.326-329
• /
• 2005

A worker who grinded the inner parts of camshafts for automobile engines using water-soluble metalworking fluid (MWF) for 14 years was diagnosed with sinusitis. We postulated that the outbreak of sinusitis could be associated with exposure to microbes contaminated in water-soluble MWF during the grinding operation. To suggest responsible agents for this outbreak, quantitative exposure assessment for chemical and biological agents and prevalence of work-related respiratory symptoms by questionnaire were studied. The exposure ranges of MWF mist (0.59 $mg/m^3$to 2.12 $mg/m^3$) measured during grinding exceeded 0.5 $mg/m^3$ of the recommended exposure limit (REL). Grinder's exposures to bacteria, fungi and endotoxins were also generally higher than not only the proposed standards, but also those reported by several studies to identify the cause of respiratory effects. Statistical test indicated that the prevalence rate of reported symptoms related to nasal cavities showed no significant differences among the operations. Evaluation on grinding operation characteristics and quantitative exposure assessment indicated that repeated exposure to MWF mist including microbes contaminated from the use of water-soluble MWF may cause respiratory diseases like sinusitis or at least increase susceptibility to the development of sinusitis

• Journal of Environmental Health Sciences
• /
• v.41 no.1
• /
• pp.24-29
• /
• 2015

Objectives: The objective of this study was to identify determine factors for blood VOCs levels in college students. Methods: Venous blood samples were collected from healthy 29 male and 25 female volunteers. The samples were analyzed with solid-phase microextraction gas chromatography and mass spectrometry. Results: Blood concentrations of benzene, toluene, ethylbenzene, m-,p-xylene, o-xylene were higher in smoking group than in non-smoking group. Geometric means of smoking group and non-smoking group were 0.45 and $0.36{\mu}g/L$ in benzene, 0.82 and $0.47{\mu}g/L$ in toluene, 0.44 and $0.41{\mu}g/L$ in ethylbenzene, 0.49 and $0.39{\mu}g/L$ in m-,p-xylene and 0.47 and $0.43{\mu}g/L$ in o-xylene, respectively. Gender, alcohol drinking, coffee, commuting time (30 minutes) by a car and adjacency between home and road were not associated with increasing blood VOCs concentrations of college students. Conclusion: Smoking habit was significantly associated with blood concentrations of benzene, toluene, ethylbenzene, o-,m-,p-xylene in college students.

• Journal of Microbiology and Biotechnology
• /
• v.19 no.9
• /
• pp.1065-1069
• /
• 2009

Of 143 clinical isolates of Klebsiella pneumoniae collected from Korean non-tertiary hospitals, 24 (16.8%) showed an extended-spectrum ${\beta}$-lactamase-positive phenotype. PCR and sequence analysis revealed the presence of TEM-116 (n=13), CTX-M-3 (n=5), CTX-M-14 (n=2), CTX-M-15 (n=3), and SHV-12 (n=16). Each of the 24 isolates encoded more than one ${\beta}$-lactamase, and seven isolates (29%) harbored two different SHV-type ${\beta}$-lactamase genes ($bla_{SHV-11}$ and $bla_{SHV-12}$) bounded by insertion sequence IS26 in a single transferable plasmid.

• Proceedings of the PSK Conference
• /
• 2003.04a
• /
• pp.138.2-139
• /
• 2003

The inhibitory effects of (1R, 9S)- and (1S, 9R)-enantiomers of $\beta$-hydrastine (BHS) on dopamine biosynthesis in PC12 cells were investigated. (1R, 9S)-BHS decreased the intracellular dopamine content with the $IC_{50}$ value of 14.3 $\mu\textrm{M}$ at 24 h, but (1S, 9R)-BHS did not. In these conditions, (1R, 9S)-BHS inhibited TH activity mainly in a concentration-dependent manner(33％ inhibition at 20 $\mu\textrm{M}$) and decreased TH mRNA level. (omitted)

• Korean Journal of Adult Nursing
• /
• v.22 no.2
• /
• pp.211-220
• /
• 2010

Purpose: This study was done to identify the relationship of trait anger, health state, physical symptoms. and general characteristics to physical symptoms and to identify factors affecting physical symptoms of elderly in urban areas. Methods: The research design for this study was a descriptive survey design using a convenience sampling. Elders (n=276), who agreed to participate in this study completed a self-reporting questionnaire. The collected data were analyzed by descriptive statistics, t-test, ANOVA, Pearson's correlation coefficients, and multiple regression. Results: Study participants reported low trait anger (M=18.61), physical symptoms (M=7.15), and moderate health state (M=3.30). The 45.4%of variance in physical symptoms was significantly explained by emotional function health state (${\beta}$=-.284, p=.013), which is one of the sub-domain of the elderly health state, and trait anger (${\beta}$=3.841, p<.001). Conclusion: Findings of this study provide that the most important factors in explaining physical symptoms for the elders in Korea were emotional function health state and trait anger. Based on the findings of this study, further nursing practice and nursing research for the elders with physical symptoms should be focused on emotional support.

• Journal of Korean Society of Occupational and Environmental Hygiene
• /
• v.11 no.1
• /
• pp.34-41
• /
• 2001

Passive samplers have been used for personal, indoor, and outdoor air monitoring of VOCs at ppb concentrations in community and office environments. The path length of modified passive sampler was shortened, so it was intended to increase an uptake rate. The performance of the modified 3M 3500 organic vapor monitor(OVM) as a tool for assessing exposures to toxic air pollutants in nonoccupational community environments was evaluated using combined controlled test atmospheres of six selected target volatile organic compounds(VOCs): benzene, methyl tert-butyl ether(MTBE), chloroform, 1,4-dichlorobenzene, tetrachloroethylene, and toluene. The experiments were conducted by exposing the dosimeters to concentrations of $50{\sim}100{\mu}g/m^3$ on six face velocity(0.00, 0.02, 0.06, 0.12, 0.20, 0.30 m/sec) for 24 hours. If the uptake rate was increased, that means that we could use the passive sampler more effectively. The uptake rates were increased linearly according to reduce the path length. Although the diffusion path length was shortened, the change of uptake rate was within ${\pm}25%$ of theoretical value, indicating that the modified passive sampler(TM) can be effectively used over the range of concentrations and environmental conditions tested with a 24-h sampling period if the face velocities were over 0.12 m/s for 6 components of VOCs. But when the face velocities were less than 0.12 m/s, uptake rates were reduced more than expected values. So, the passive sampler with the shortened path length should be used at indoor or outdoor environment where the face velocity should be over about 0.10 m/s. If the path length was shortened more, the uptake rate was more effected by starvation.

• Journal of the Korea Society of Computer and Information
• /
• v.16 no.12
• /
• pp.59-69
• /
• 2011

Recently, as people's interest in health care has been rising, the health care service awareness and utilization has been increasing. However, the existing healthcare services have problems such as inconvenience of mobility, the low reliability of input for information and low accuracy of information provided as well. in this study, we developed the m-Health application by utilizing smart phone with improvement of these problems. This application provided the total of 5 services such as notification for risk of cardiovascular disease, personalized dietary recommendations targeted to 20s and 30s who do not properly manage their health care by bad habits. In addition, the benefits and problems of these services were found out through the analysis for the general importance and satisfaction of these services by Importance-Performance Analysis (IPA) technique. In result of IPA analysis, The six items such as 'input accuracy and reliability of information', 'content reliability', 'proper health service recommendations', etc. among 12 of the items needed to receive the effective services on m-Health were belonged to importance and satisfaction area with high level. And, in the 'information security', the importance is high but the satisfaction was low. In conclusion, the further study for strengthening security of information, service update provided with PHR to consistently keep the advantage of these services will be conducted.