• 대한수학회보
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• 제51권5호
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• pp.1269-1279
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• 2014

The equations arising from the thermoelastic theory are analyzed in a linear approximation. First, we establish the convergence result on the coefficient c. Next, we establish that the solution depends continuously on changes in the coefficient c. The main tool used in this paper is the energy method.

• Tuberculosis and Respiratory Diseases
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• 제76권6호
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• pp.276-283
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• 2014

Background: We aimed to investigate the role of the physician in practice and the factors that influence the success rate of smoking cessation. Methods: This study retrospectively analyzed 126 adult smokers who had visited the outpatient department of pulmonology, and received motivational interviewing with or without supplement drugs. The findings include continuous smoking abstinence rate, which was evaluated at 6, 12 and 24 weeks, and the factors associated with continuous abstinence for 6 months or longer. Results: The patients with only motivational interviewing accounted for 57.9%, while the nicotine patch therapy was applied to 30.2%; and varenicline was prescribed to 11.9%. The smoking cessation success rates of at 6, 12, and 24 weeks were 55.6%, 47.6%, and 33.3%, respectively. However, even in the failure group at six months, tobacco consumption was decreased under 10 cigarettes per day in 42.1% (53/126). In multivariate logistic regression analysis, degree of Fagerst$\ddot{o}$m Test for Nicotine Dependence (p=0.034; odds ratio, 3.607; 95% confidence interval [CI], 1.102-1.807), the absence of smoking-related lung disease (p=0.008; odds ratio, 4.693; 95% CI, 1.497-14.707), and education level (p=0.001; odds ratio, 181.420; 95% CI, 8.414-3,911.502) were the predictors of successful smoking cessation. Conclusion: An improved continuous smoking abstinence rate can be obtained by motivational interviewing, regardless of the association with pharmacotherapy.

• Human Ecology Research
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• 제54권3호
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• pp.321-332
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• 2016

This study clarified the maintenance of relationship between children and teachers based on longitudinal data and explored the latent classes. It clarified the latent classes connection with the children's peer play interaction. The subjects of this study were 194 children (aged 3) who attended 11 different kindergartens and daycare centers. We collected data three times (once every 6 months) until they reached age 4. The results of this study were: first, closeness, conflict, and dependence of child-teacher relationship that showed a continuous short-term connection. Second, we classified the child-teacher relationship into three groups according to longitudinal data. Those groups were, 'low level maintenance group' which had the lowest conflict and dependence compared to the highest closeness with teacher, 'middle level maintenance group' which had the teacher relationship in the middle level of the sub element area, and 'high level maintenance group' which showed high conflict and dependence compared to low closeness with the teacher. Third, the group which maintains a longitudinal high conflict.dependence showed more interruption and disruption behavior than the group which maintained a low conflict and dependence. In conclusion, the child-teacher relationship seemed to be the steady characteristic because it showed the early formation of a stable relationship. It was possible to predict the child's peer interaction through an early child-teacher relationship. Teachers need to be educated by the kindergarten and daily care center because the early formation of a child-teacher relationship can be the foundation of child's later peer and teacher relationships.

• Tuberculosis and Respiratory Diseases
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• 제85권4호
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• pp.349-357
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• 2022

Background: The most consistently identified mortality determinants for the new coronavirus 2019 (COVID-19) infection are aging, male sex, cardiovascular/respiratory diseases, and cancer. They were determined from heterogeneous cohorts that included patients with different disease severity and previous conditions. The main goal of this study was to determine if activities of daily living (ADL) dependence measured by Barthel's index could be a predictor for COVID-19 mortality. Methods: A prospective cohort study was performed with a consecutive sample of 340 COVID-19 patients representing patients from all over the northern region of Portugal from October 2020 to March 2021. Mortality risk factors were determined after controlling for demographics, ADL dependence, admission time, comorbidities, clinical manifestations, and delay-time for diagnosis. Central tendency measures were used to analyze continuous variables and absolute numbers (proportions) for categorical variables. For univariable analysis, we used t test, chi-square test, or Fisher exact test as appropriate (α=0.05). Multivariable analysis was performed using logistic regression. IBM SPSS version 27 statistical software was used for data analysis. Results: The cohort included 340 patients (55.3% females) with a mean age of 80.6±11.0 years. The mortality rate was 19.7%. Univariate analysis revealed that aging, ADL dependence, pneumonia, and dementia were associated with mortality and that dyslipidemia and obesity were associated with survival. In multivariable analysis, dyslipidemia (odds ratio [OR], 0.35; 95% confidence interval [CI], 0.17-0.71) was independently associated with survival. Age ≥86 years (pooled OR, 2.239; 95% CI, 1.100-4.559), pneumonia (pooled OR, 3.00; 95% CI, 1.362-6.606), and ADL dependence (pooled OR, 6.296; 95% CI, 1.795-22.088) were significantly related to mortality (receiver operating characteristic area under the curve, 82.1%; p<0.001). Conclusion: ADL dependence, aging, and pneumonia are three main predictors for COVID-19 mortality in an elderly population.

• Communications for Statistical Applications and Methods
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• 제17권4호
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• pp.493-505
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• 2010

Developing a test for independence of random variables X and Y against the alternative has an important role in statistical inference. Kochar and Gupta (1987) proposed a class of tests in view of Block and Basu (1974) model and compared the powers for sample sizes n = 8, 12. In this paper, we evaluate Kochar and Gupta (1987) class of tests for testing independence against quadrant dependence in absolutely continuous bivariate Farlie-Gambel-Morgenstern distribution, via a simulation study for sample sizes n = 6, 8, 10, 12, 16 and 20. Furthermore, we compare the power of the tests with that proposed by G$\ddot{u}$uven and Kotz (2008) based on the asymptotic distribution of the test statistics.

• Journal of the Optical Society of Korea
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• 제4권2호
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• pp.94-99
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• 2000

Optical monitoring using the chromatic aberration of focusing optics is applied to auto-focus control in laser welding. The spectral transmittance of thermal radiation from a weld pool through an aperture depends on the wavelength of the spectral band and on the distance of the weld pool from the focusing optics. Its dependence has been used to monitor the focus shift in laser welding by measuring the spectral band signals filtered by the aperture. The difference between pulsed and continuous laser welding is analyzed. Furthermore, the dependence of the focus shift monitoring on the weld pool size variation is optimized to monitor the focus shift independently from the laser power change at the weld pool. The performance of the auto-focus control with chromatic filtering is presented for pulsed laser welding.

• 대한간호학회지
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• 제37권7호
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• pp.1139-1148
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• 2007

Purpose: The purpose of this study was to investigate the effects of a community-based group smoking cessation program among adult smokers in a rural community. Method: The study design was quasi-experimental with a pre and posttest. A total of 55 adult smokers participated in the study. They were evaluated 1, 3, and 6 months after the program to identify the long-term effectiveness of the program. The program consisted of a total of 5 sessions provided twice a week. To test the effectiveness of the program, urine creatinine, expired air carbon monoxide, nicotine dependence, and smoking-related knowledge were used as dependent variables. Data was analyzed with the SPSS 10.0 program with a t-test, paired t-test, and Scheffe test. Result: Urine creatinine, expired air carbon monoxide, and nicotine dependence were significantly decreased after the program. Also, the rates of continuous abstinence were 81.8% at posttest, 65.5% at 1 month, 54.5% at 3 months, and 54.5% at 6 months follow-up. Conclusion: This community-based group smoking cessation program implemented by a nurse and smoking cessation counselors was effective for quitting smoking and decreasing urine creatinine and nicotine dependence. Therefore, this smoking cessation program could be recommended to induce smoking cessation as health promotion management in the rural community.

• 대한수학회지
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• 제33권4호
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• pp.1039-1046
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• 1996

In the theory of partial differential equations with given initial values and boundary values one usually investigates to examine the well-posedness, that is, the unique existence of the solution as well as its continuous dependence on the data. This theory is strong enough for us to determine the situation anywhere and anytime provided that the initial data are actually given. However, in many cases the data are not completely known for us. Then in those situations arise the new problem to determine the unknown initial data by taking other conditions for the solutions.

• 대한수학회지
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• 제48권4호
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• pp.867-885
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• 2011

We study a class of quasilinear wave equations with strong and nonlinear viscosity. By using the perturbation method for semilinear parabolic equations, we have established the fundamental results on existence, uniqueness and continuous dependence on data of weak solutions.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1998년도 하계종합학술대회논문집
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• pp.395-397
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• 1998

NH$_{3}$ gas sensitive ZnO:Al, In thin films were prepared by the heat treatment following continuous deposition of very thin In layer and ZnO:Al layer to obtain the modified surface morphology for good sensitivity. Dependence of the structural electrical and optical properties of them on heat treatment temperature was investigated by x-ray diffraction, SEM, 4-point probe method and spectrophotometer.