• Elastomers and Composites
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• v.44 no.2
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• pp.156-163
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• 2009

Our objective is to increase the flowability of Polypropylene(PP) compounds and achieve flow mark free surface in injection molded specimen. We have investigated flowabilities of PP compounds which were composed of PP, rubber, talc, and trace amount of additives. Flowability measurement was performed with four types PPs of which molecular weight distributions(MWD) and melt indexes(MI) were different. Rheological properties of the PP compounding materials, such as spiral flow(SF) length, MI, and shear viscosity, were evaluated. When PP with the broad MWD was used, there were remarkable cases where the spiral flow length of low MI PP compound was longer than that of higher MI PP compound. The PP compound having low MI but broad MWD PP has more flowability than the compound with only high MI.

• Child Health Nursing Research
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• v.18 no.3
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• pp.150-156
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• 2012

Purpose: The main purposes of this study were to assess maternal-fetal attachment (MFA) of the expectant mothers of a fetus with a prenatal diagnosis of congenital heart disease (CHD) and to identify factors associated with MFA. Methods: The methodology was a cross sectional survey study using a self-administered questionnaire. Thirty pregnant women carrying a fetus with a prenatal diagnosis of CHD and 30 pregnant women with a normal fetus were enrolled in this study. The MFA Scale and PPS (The Prenatal Psychosocial Profile) were used to collect data. Data were analyzed using SPSS 20.0 Window version. Descriptive statistics, $X^2$-test and t-test were used to compare the two groups. The factors associated with MFA were identified by multiple regression analysis. Results: There was no significant difference between the two groups in MFA and social support from spouse was the only variable showing a significant difference. The model from the multiple regression analysis explained 33.8% of MFA for both groups. Conclusion: MFA of expectant mothers with a prenatal diagnosis of CHD and of mothers with a normal fetus were not significantly different. It is important that health care providers encourage expectant fathers to support the expectant mothers to increase MFA.

• Proceedings of the KIEE Conference
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• 2006.07c
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• pp.1550-1551
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• 2006

An L-band linear accelerator system for e-beam sterilization is under design for bio-technology application. The klystron-modulator system as RF microwave source has an important role as major components to offer the system reliability for long time steady state operation. A PFN line type pulse generator with a peak power of 71.5-MW, $7{\mu}s$, 285 pps is required to drive a high-power klystron. The high power pulse transformer has a function of transferring pulse energy from a pulsed power source to a high power load. The pulse transformer producing a pulse with a peak voltage of 275 kV is required to produce 30-MW peak and 60 kW average RF output power at the frequency of 1.3-GHz. We have designed the high power pulse transformer with 1:13 step-up ratio. The peak and average power capability is 71.5-MW (275 kV, 260 A at load side with $7{\mu}s$ pulse width) and 130 kW, respectively. In this paper, we present a system overview and initial design results of the high power pulse transformer.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.1079-1081
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• 2007

An L-band Linear Accelerator System for E-beam sterilization is under construction for bio-technology application. The klystron-modulator system as an RF microwave source has an important role as major components to offer the system reliability for long time steady-state operations. A PFN line type pulse generator with a peak power of 71.5-MW, $7\;{\mu}s$, 285 pps is required to drive a high-power klystron. The high power pulse transformer has a function of transferring pulse energy from a pulsed power source to a high power load. The pulse transformer producing a pulse with a peak voltage of 275 kV is required to produce 30-MW peak and 60 kW average RF output power at the frequency of 1.3-GHz. We have designed the high power pulse transformer with 1:13 step-up ratio. The peak and average power capability is 71.5-MW (275 kV, 260 A at load side with $7\;{\mu}s$ pulse width) and 130 kW, respectively. In this paper, we present measurements and its analysis on the design parameters, and an initial test result as well as a design concept on the high-power pulse transformer.

• Journal of the Korean Society of School Health
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• v.22 no.1
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• pp.49-59
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• 2009

Purpose: The aim of this study was to identify the factors related with the intention of smoking abstinence among elementary students in a metropolitan city in Korea. Methods: All the elementary schools in the city were stratified by region, and then schools as a primary sampling units (PSU) were selected by probability proportional to size (PPS) sampling. One class per grade was sampled randomly from 5th and 6th grade in the sampled schools from October to December in 2004. The students completed a standardized self-administered questionnaire anonymously. A total number of 1,712 respondents who did not smoke was included in the final analysis. The dependent variable was an intention of smoking in the future, and it was dichotomized into 'absolutely confident in smoking abstinence' and 'others'. The risk of non-absolute confidence in smoking abstinence was calculated with simple and multiple logistic regression, which were conducted with STATA 9.0 by a design-based analysis considering strata variable, PSU, and sampling weight. Results: In the final model of multiple logistic regression analysis, those who were more likely to have non-absolute confidence in smoking abstinence were male students (OR=2.66, p<0.001); barely attending religious services (OR=3.32, p=0.002) or having no religion (OR=1.95, p=0.027); exposure to environmental tobacco smoke outside home 1${\sim}$2 days per week (OR=1.60, p=0.013); having friends who smoked (OR=1.93, p=0.011); non-absolute confidence in refusing to smoke (OR=5.35, p<0.001); having relatively less negative attitude (OR=2.88, p<0.001), positive attitude (OR=2.35, p<0.001), and indifference (OR=4.05, p=0.034) toward peer smoking; not good relationship with mother (OR=1.52, p=0.016). Conclusion: The factors related with non-absolute confidence in smoking abstinence were coincided with those of smoking among children. The results of this study suggest the smoking prevention education should be applied to the children more actively, especially who are not confident in smoking abstinence in the future.

• The Journal of Pediatrics of Korean Medicine
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• v.27 no.2
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• pp.1-10
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• 2013

Objectives The aim of this study was to explore the effect of parental attitude on the behavioral problems in children who visited the traditional Korean pediatrics clinic. Methods The subjects were consist of 190 outpatients ($56.6{\pm}12.9$ months) and their mother. The Behavior problems of children were measured with Korean version of Child Behavior Checklist for Ages 1.5-5 (K-CBCL1.5-5) while parental perception of child vulnerability, parent overprotection, parenting stress were measured by Child Vulnerability Scale (CVS), Parent Protection Scale (PPS), Korean-Parenting Stress Index-Short Form scale (K-PSI-SF), respectively. Correlation and multiple regression were conducted for the analysis. Results Significant correlations between child total problems score and child vulnerability (r=.272, p<.001), parent overprotection (r=.243, p=.001), and parenting stress (r=.597, p<.001) were reported. Multiple regression analysis revealed that the parenting stress (${\beta}$=.548, p<.001) was a major predictor for the child behavior problems rather than child vulnerability and parent overprotection. Conclusions It was shown that the parenting stress has a significant influence on the emotional and behavioral development of children. These results can be useful for improving clinical diagnosis and treatment in traditional Korean pediatrics.

• Journal of Technology Innovation
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• v.29 no.3
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• pp.91-119
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• 2021

The importance of industrial policy and innovation policy perspectives on public procurement has recently been highlighted. In particular, there have been discussions and studies on whether public procurement directly affects the growth and innovation of SMEs. As an extension of this study, this study analyzes whether the age of a firm moderating the effect of public procurement on growth among the characteristics of firms participating in public procurement. The analysis data was constructed by matching the financial data of about 1,247 firms designated as excellent products by the Public Procurement Service(PPS) from 2006 to 2017 and the public procurement sales. As a result of analysis through the panel regression model, firms with a greater degree of public procurement showed a higher growth rate, and this relationship was stronger with younger firms. This result not only contributes to the existing academic discussion on the effectiveness of public procurement, but also has significance in the establishment of public procurement policy.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.13 no.4
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• pp.13-28
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• 2003

The Protection Profile(PP) is a common security function and detailed statement of assurance requirements in a specific class of Information Technology security products such as firewall and smart card. The parts of TOE security environment in the PP have to be described about assumption, treat and security policy through analyzing purpose of TOE. In this paper, we present a new security policy derivation among TOE security environment parts in the PP. Our survey guides the organizational security policy statements in CC scheme through collected and analyzed hundred of real policy statements from certified and published real PPs and CC Toolbox/PKB that is included security policy statements for DoD. From the result of the survey, we present a new generic organizational policy statements list and propose a organizational security policy derivation method by using the list.

• Korean Journal of Clinical Pharmacy
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• v.30 no.4
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• pp.264-269
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• 2020

Background: Inflammatory diseases can increase the prevalence of anemia. Recent studies confirmed that the prevalence of anemia is increased by atopic dermatitis (AD), a chronic inflammatory disease. Therefore, we aimed to elucidate the correlation between AD severity and prevalence of anemia. Methods: We used data of pediatric patients from the Health Insurance Review and Assessment Service (HIRA-PPS-2016). We included pediatric patients (<18 years) with AD diagnosis who were prescribed medications for AD. We applied a propensity score method with inverse probability of treatment weighting (IPTW) adjusting for differences in prevalence of confounders and performed IPTW logistic regression to evaluate associations between the anemia and severity of AD. Results: In total, 91,501 patients (mild AD: 47,054 patients; moderate-to-severe AD: 44,447 patients) <18 years who were prescribed drugs for AD were analyzed. Analysis of the probability of patients with mild AD and prevalence of anemia as a reference revealed an odds ratio (OR) of 1.159 (95% CI, 1.109-1.212; p<0.001) in moderate-to-severe AD patients, indicating a correlation between anemia prevalence and AD severity. Subgroup analysis according to gender, age group, and type of health insurance revealed there was an association between AD severity and anemia except in patients equal or older than 7 years. Conclusion: The prevalence of anemia increased with AD severity despite adjusting for confounding factors. Our results support the hypothesis that AD can cause anemia, and anemia prevalence could be increased in severe AD patients. Further studies are needed to establish a pathological basis.

• The Journal of Pediatrics of Korean Medicine
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• v.36 no.2
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• pp.1-12
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• 2022

Objectives We analyzed visiting patterns to medical institutions and cost per visit according to the common cold patients aged 0-19 years. We analyzed Korean medical treatment for common cold. Methods Using the Pediatric Patient Sample data of the Health Insurance Review and Assessment Service (HIRA-PPS), we analyzed the data on health insurance claims of approximately 1 million people from 2017 to 2019. The data included the number of patients who visited the hospital due to common cold for the first and second time, the ratio of second visits by type of medical institution, and the status of prescriptions in Korean medical institutions. Results The number of patients visiting healthcare providers for common cold was higher in Western medical institutions than in Korean medical institutions. However, the number of second visits was higher in Korean medical institutions. Acupuncture is the most commonly used medical treatment in Korean medical institutions for common cold. Herbal medicine for common cold was usually prescribed for 2-3 days for children and adolescents. Conclusions Although the average medical cost of Korean medical institutions was higher than that of Western medical institutions, the rate of second visits to Korean medical institutions was higher because of the demand for Korean medical treatment