• Journal of Korean society of Dental Hygiene
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• v.12 no.3
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• pp.543-551
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• 2012

Objectives : School-age children have mixed dentition and are sensitive to dental caries. Their dental condition is more important as it is directly related with oral health in their life, and parents' attention and education are necessary as the children can not manage their oral health voluntarily. Methods : To evaluate the effect of parents' occupational status on the oral health of children, this study conducted a questionnaire survey and analyzed the results along with the results of oral examination with 952 students and their parents of an elementary school located in Ulsan conducting school oral health projects on May, 2009. Results : As dental caries prevalence rate recorded 33.7%, 56.8% and 66.9% in non-dual income, professional dual income and non-professional dual income families, respectively, the rate of children of dual income families was significantly higher than that of non-dual income ones (p<0.05). Conclusions : For professional dual income families, although working mothers contribute to economic stability, they took less time to care or to educate their children compared to no-working mothers so that they need to pay more attention to oral health of children. In addition, more interest to and education for children of non-professional dual income families showing relatively lower socio-economic level and lack of time for children, were also necessary in school projects on oral health education and prevention.

• Journal of Korean Home Economics Education Association
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• v.18 no.3 s.41
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• pp.163-173
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• 2006

The purpose of this study was to investigate the marital satisfaction and family strengths in dual-Income teachers. The subjects of this study were 289 dual-income teachers in the Gyeongnam Area. Korea. The major findings obtained from this study are summarized as follows: 1) The degree of marital satisfaction of the dual-Income teachers was 5.22 on a scale of 0-7.0. The significant variables were sex, the educational degree, religion, the type of family. housework-helper, self-esteem and job satisfaction in dual-Income teachers. 2) The degree of family strengths of dual-Income teachers was 3.88 on a scale 0-5.0. The significant variables were economic level, self-esteem, job satisfaction, and marital satisfaction in dual-Income teachers. 3) There was a close correlation between the marital satisfaction and family strengths in dual-Income teachers.

• Journal of IKEEE
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• v.26 no.2
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• pp.271-279
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• 2022

This paper proposes an advanced dead-time compensation method for dual inverter with a floating capacitor. The dual inverter with floating capacitor is composed of double two-level inverters and a bulk electrolytic capacitor. The output voltage of the dual inverter is dropped by the conduction voltage of the power semiconductors. The voltage drop and dead-time cause the fundamental and harmonic distortions of output currents. When supplied power for OEW-load is low, the dual inverter operates as single inverter for effective operation. The dead-time compensation method for the dual inverter operated as single inverter is needed for reliability. The proposed method using band pass filter in this paper compensates dead-time, dead-time error and changed voltage drop error of power semiconductors for the dual inverter and dual inverter operated as single inverter. The effectiveness of the proposed method is verified by simulation results.

• Journal of Practical Engineering Education
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• v.15 no.1
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• pp.199-208
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• 2023

Performance analysis for work-learning dual system has been mainly conducted from the perspective of diagnosing the effectiveness of policies at the macro level. This study aims to analyze issues in organizational management of the work-learning dual system training center by conducting an analysis focusing on the organizational performance of the work-learning dual system training center's employees. As a result of the analysis, it was confirmed that the perception and attitude of employees toward the work-learning dual training center differed depending on the type of work-learning dual system and the type of employment contract. Among the types of work-learning dual system, overall, in the case of IPP, the organizational performance of employees was low, while the apprenticeship was relatively high. As for the type of employment contract, the need for institutional improvement has been derived, especially for the project contract workers.

• Journal of Families and Better Life
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• v.16 no.1
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• pp.81-94
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• 1998

The purpose of this study is to examine men's role conflicts of dual-earner family based on man's role type. Man's role type is composed of man's sex role attitude and family-role performance and categorized in four types such as traditionalism type neo-traditionalism type equalitarianism type and inconsistancy type. The test analysis can be summarized as follows; First test analysis can be summarized as follows; role performance and man's role conflict as working hours is long wife's role requirement is high family-role conflict as working hours is long wife's role requirement is high family-role is not commit man's role conflict directly affected. In addition indirect affect through family-role performance shows that man's role conflict level is low as level of income is high level of income difference between man and wife is low child is younger and intent to modern sex-role attitude. Second looking into the difference role conflict to man's role type it shows that equalita ianism type's role conflict is low and man's role conflict in traditionalism and neo-traditonalism types is high.

• Tribology and Lubricants
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• v.33 no.3
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• pp.85-91
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• 2017

This work studies the flow behaviors in the gap between the friction pad and separator in wet-clutch systems. The fluid volume of the lubricant is modeled using the entire system of wet-clutch pack of a dual clutch transmission that has larger outer radius of odd gear shifts and smaller inner radius of even gear shifts. Flow behaviors in the gap of the clutch pad are computed using the gear shift modes that consider the real relative velocities between the friction pad and separator. Flow behaviors in the gap of the disengaged clutch pad are mainly investigated for the wet-clutch system, whereas the engaged clutch pad is modeled with no fluid rate through the contacting surfaces. The developed hydrodynamic fluid pressures and velocity fields in the clutch pad gap are computed to obtain the relevant information for managing flow rates in wet-clutch packs under dual operating conditions during gear shifts. These hydrodynamic pressures and velocity fields are compared on the basis of each gear level and gap location, which is necessary to determine the effects of groove patterns on the friction pad. Shear stresses in the gap locations are also computed on the basis of the gear level for the inner and outer clutch pads. The computed results are compared and used for the design of cooling capacity against frictional heat generation in wet-clutch pack systems.

• Journal of Pharmaceutical Investigation
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• v.38 no.3
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• pp.177-182
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• 2008

The purposes of this study were to prepare dual-layered coated compact pellets containing three nutrients Glucose, Chromium picolinate, Vitamin C) for rumen bypass. The core compact pellets were prepared by an extrusionspheronization method and then double layered coated with pH independent EC (ethyl cellulose) and pH-dependent polymers ($Eudragit^{(R)}$ E100) using a fluid-bed spray coater. Depending on the coating levels of EC and $Eudragit^{(R)}$ E100, release profiles were variable in simulated rumen (pH 6.8) and abomasums (pH 2.0) fluid using USP apparatus I (basket method). When compact pellets were coated with EC (about 10% level in inner layer) and then $Eudragit^{(R)}$ E100 (20% level in outer layer) in a dual-layered manner, rumen-bypass delivery resisting rumen fluid followed by release in abomasums fluid could possible. The friability was also satisfactory based on chewing behavior of ruminants. The dual-layered coated compact pellets showed smooth surface and distinct inner/outer layers using scanning electron microscopy (SEM). The current rumen bypass delivery system can be also applicable to deliver other nutrients in ruminants.

• Journal of Family Resource Management and Policy Review
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• v.20 no.4
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• pp.49-68
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• 2016

Fathers are increasingly expected to participate in parenting due to the higher participation of women in economic activities, the growing awareness of gender equality, and the greater emphasis on the role of fathers. The purpose of this study was to examine the effects of paid work time and jobs' family-friendly policies on parenting participation in dual-earner families. Questionnaires were distributed to 577 fathers of dual earner families through a child care center in the Gyeongsangbukdo Province, and the results were analyzed using SPSS 18.0 for Windows. The statistical methods employed included mean, standard deviation, the Pearson correlation analysis, and a multiple regression analysis. The main results are as follows. First, the fathers of dual-earner families showed an above average level of participation in parenting (3.26). By category, they were less involved (2.89) in household chores, and more active in daily guidance and leisure activities (3.48). Second, the most significant variable affecting fathers' parenting participation was having a regular office-closing time. Fathers who were younger, had a higher level of education, had a regular office-closing time, had more vacation leave, and whose companies implemented family-friendly policies were more likely to participate more actively in parenting. Third, the key factors influencing fathers' parenting participation by sub-category were found to be having a regular office-closing time and jobs with family-friendly policies. Fathers with a greater awareness of gender equality were more inclined to participate in household chores, while those who were younger and more educated actively participated in daily guidance and leisure activities.

• Nuclear Engineering and Technology
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• v.49 no.7
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• pp.1563-1570
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• 2017

In order to perform dry interim storage and transportation of the spent-fuel assemblies of the Bushehr Nuclear Power Plant, dual-purpose casks can be utilized. The effectiveness of different neutron-shield materials for the dual-purpose cask was analyzed through a set of calculations carried out using the Monte Carlo N-Particle (MCNP) code. The dose rate for the dual-purpose cask utilizing the recently developed materials of $epoxy/clay/B_4C$ and $epoxy/clay/B_4C/carbon$ fiber was less than the allowable radiation level of 2 mSv/h at any point and 0.1 mSv/h at 2 m from the external surface of the cask. By utilization of $epoxy/clay/B_4C$ instead of an ethylene glycol/water mixture, the dose rates on the side surface of the cask due to neutron sources and consequent secondary gamma rays will be reduced by 17.5% and 10%, respectively. The overall dose rate in this case will be reduced by 11%.

• Journal of the Korea Safety Management & Science
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• v.11 no.4
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• pp.161-168
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• 2009

Ubiquitous application is in need of high-level technology to meet various requests for ubiquitous service. In order to adopt ubiquitous technology in not only pilot projects but also regional services, many projects like u-City are implemented in and outside the country. RFID has been known as one of the important technology to provide with core benefits of Ubiquitous services. Because each band of RFID technology has merits and demerits concurrently, single-band RFID system has limitations for various RFID services. Thus, we developed dual-band RFID system enable to provide with 13.56MHz and 2.45GHz RFID service at the same time to compensate the shortage of single-band RFID system. Also we have considered the way that the firmware would control signals without collision, studied battery life and range for tag, and made hardware for dual-band RFID service.