• Journal of Korean Society for Quality Management
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• v.39 no.2
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• pp.320-328
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• 2011

This research proposes comprehensive models for analyzing common cause failures (CCF) due to cumulative shocks and to assess system reliability under the CCF. The proposed cumulative shock models are based on the binomial failure rate (BFR) model. Six kinds of models are proposed so as to explain diverse cumulative shock phenomena. The models are composed of the initial failure probability, shape parameter, and the total shock number. Some parameters of the proposed models can not be explicitly estimated, so we adopt the Expectation-maximization (EM) algorithm in order to obtain the maximum likelihood estimator (MLE) for the parameters. By estimating the parameters for the cumulative shock models, the system reliability with CCF can be assessed sequentially according to the number of cumulative shocks. The result can be utilizes in dynamic probabilistic safety assessment (PSA), aging studies, or risk management for nuclear power plants. Replacement or maintenance policies can also be developed based on the proposed model.

• International Journal of Railway
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• v.7 no.3
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• pp.80-84
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• 2014

The purpose of this paper was to review Intelligent Compaction (IC) techniques, which is regarded relatively new to the railroad roadbed construction activity. Most of civil structures are built on roadbed that supposed to provide adequate load bearing support to the upper structure through the qualified compaction process. However, it is not uncommon for structure failure attributed to inadequate compaction control take place in field sites. Unlike traditional compaction control method to check field density at several locations, IC techniques continuously measure various compaction quality indices that represent compaction uniformity. In this paper, a series of literature review relevant to IC techniques was conducted to provide concise summary on the following categories: 1) background of IC technique; 2) Summary of IC vendors and basic principles; 3) modeling of IC behavior, and 4) case study along with correlation between IC with other measurements. In summary, IC technologies seem to be promising in future railroad construction to achieve better compaction quality control so that the serviceability of railroad can be ensured with minimizing rehabilitation and maintenance activities.

• International conference on construction engineering and project management
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• 2015.10a
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• pp.604-605
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• 2015

To secure quality of dam construction needs appropriate construction duration. Tight construction schedule may have negative influence on infrastructure quality, work safety and maintenance cost. It is necessary to reflect proper construction duration in the planning phase. There have been standards for estimating construction duration of building and industrial complex development but dam construction have not. In order to estimate construction duration of CFRD, feasible study reports and design reports were analyzed to acquire available information. After that, considering on construction duration methods such as comparison with similar cases, approximate estimating formula, approximate quantity assumption were adapted to Critical Path items. Hence, this study present framework for construction duration estimating of CFRD in the planning phase. This framework can be applied other types of dam along the same line.

• Journal of Wetlands Research
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• v.17 no.2
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• pp.184-192
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• 2015

This study is a basic research for low maintenance constructed wetlands which can prevent water quality deterioration due to wetland soils. The purpose of this study is to analyze water quality control mechanisms of constructed wetland on the artificial ground which installed the modular revetment structure(MRS), a device that separates water and soil. This study was then conducted with two different wetland mesocosms (a treatment plot and a control). These mesocosms were monitored to analyze effects of water quality control of the MRS. A treatment plot was built, and separated into soil and water, by filling the MRS with the decomposed granite soil in the mesocosm made of rubber material. A control plot was built where the decomposed granite soils were exposed to water by leaving the soil on the bottom of the mesocosm made of rubber material. Water quality was then analyzed by using Kolmogorov-Smirnov Z examination which then showed that pH, BOD, SS, Chl-a, T-P, T-N had statistically valid difference between a container with the MRS and one without it. According to the analysis of the water quality, the temperature and the EC level came out similarly and both mesocosm showed same level on pH and DO. A treatment plot had higher levels of BOD, SS Chl-a, and T-P. A control plot's T-N value was little lower than that of the treatment plot. This study suggests method of constructed wetlands using the MRS prevents problems occurring in wetland soils: aridity of wetlands by soil erosion, eutrophication, and algal blooms due to nutrients released from wetland soil. These functions of constructed wetland with the MRS increase aesthetic, ecologic, social, and economic value of the wetland. Outcomes of this research will later enable more proficient way of stabilizing water quality and provide data for planning low maintenance constructed wetlands.

• 한국태양에너지학회:학술대회논문집
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• 2008.11a
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• pp.112-119
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• 2008

In order to ensure building energy management at an appropriate level continuously, it is necessary to define clearly service work of energy management and to suggest evaluation index whether energy management in buildings is fit and improvement is needed or not. But, evaluation index of energy management level in buildings is not suggested yet in Korea. So, the purpose of this paper is to suggest evaluation index of energy management level in buildings, investigate the present state of Korean buildings and evaluate energy management levels. As a result of surveys of evaluation index of energy management, it is found that portion of level 1, which is the best level, is higher than any other level, level 2, level 3. And, throughout analysis, it is found that as total floor area is larger, evaluation index of energy management level is better, and, in order to increase energy management level, first of all, there is necessary for building's users to change understanding about energy saving and make a reform of national policy of energy management in buildings. Because there is rich relationship between items among evaluation index of this stuff and result value of evaluation index, evaluation index of energy management suggested in this study is available to evaluate energy management level in buildings.

• The Journal of Pediatrics of Korean Medicine
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• v.27 no.3
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• pp.65-73
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• 2013

The subjects were composed of 308 children who visited the department of pediatrics, ${\bigcirc}{\bigcirc}$ korean medicine hospital from January 2010 to May 2013. Results 1. Among 308 patients, there were 188 boys and 120 girls; their ratio was 1.57:1. The age distribution showed that 38.3% were in the age less than 1 years, 38.0% in 1 years, 7.8% in 2 years, 5.2% in 3 years, 3.3% in 4~5 years, 4.5% in 6~10 years, 2.9% in 19~21 years. 2. It was found that 36.7% of the sleep disorder was caused without motivation, 17.2% caused by negligent accidents, 13.9% by traffic accidents, 10.4% by the unfamiliar environment, 8.1% by separation from parents, 7.5% after suffering disease, and 6.2% by irritating sound. 3. The sleep onset insomnia accounts for 17.2% of sleep disorder, sleep maintenance insomnia for 67.5%, poor sleep quality 24.4%, and daytime sleep disorder takes 19.8%. The ratio of sleep onset insomnia in adolescence comprises larger proportion (44.4%) than it of any other age groups. 4. The symptoms complicated with sleep disorder are the respiratory infection which takes 25.3%, being easily startled 18.2%, anorexia 14.6%, soft stools frequency 13.0%, greenish stools 10.7%, and skin rash 10.7%. Conclusions The causes of sleep disorders, changes of sleeping patterns, and complicated diseases show diversity in children and adolescence. Further study of sleep disorders in children and adolescence should be progressed as well.

• Korean Journal of Childcare and Education
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• v.10 no.4
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• pp.5-28
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• 2014

South Korea has strengthened the eligibility criteria for childcare teachers while amending the Infant Care Act in January 2005 in order to improve the quality of childcare services. Since then, there was a change in the legal basis related to childcare staff such as introduction of national certification of childcare center directors, name change, strengthened qualification standards for directors and teachers, training system maintenance and repair, strengthened credit standards of teachers' care related qualification courses, and maintenance provisions of continuing education nursery teacher qualifications. And that is because childcare staff are closely related to the quality of childcare, and a very important variable who has direct influence on infants. This study, through literature research and analysis, describes the status and development direction of childcare staff. This study covers three main aspects. First, the relevant historical flow was reviewed and the concepts of the role, expertise, and legal status of childcare staff were investigated. Second, staff training institutions, emissions certification, employment, and the status of treatment were investigated. Third, development direction for the training system, eligibility criteria, continuing education and its training system, and treatment improvement were proposed.

• Journal of the Korean Society of Clothing and Textiles
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• v.32 no.8
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• pp.1179-1189
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• 2008

The purpose of this study is to investigate the satisfaction of the adolescents' school backpack bag and the important criteria when purchasing for developing comfort and functional backpack. The questionnaire was composed and surveyed with 245 middle school students and the data were analyzed through SPSS 13.0. Purchasing criteria were grouped into 5: practical, shop environment, comfort, aesthetic and maintenance. Satisfaction factors were function/comfort, fashion/aesthetic and durability/A.S. 50.2% of students recognized the inappropriate wearing backpack might cause the deformation of body shape. And the wrong habit of wearing bag was found to affect the body posture of students. Main symptoms caused by wearing it for long time are ‘sweating around shoulder and back' and ‘feeling stiff in shoulders and waist'. Needs arise to develop the bag which could prevent them and to educate students how to wear bags. According to the result from MDS of purchasing criteria, one axis is product vs. environment, and other is functional vs. psychological aspects. According to the result from MDS of bag satisfaction, one axis is function/durability vs. fashion/appearance, and other is gestalt quality vs. part quality. They wanted the improvement in the aspects of shape/design, material, maintenance, comfort and usability of the bags. Specially it is required that we research the adolescent customer-oriented way and develop the new materials or shapes pursuing both shoulder comfort and characteristics.

• Journal of the Korea institute for structural maintenance and inspection
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• v.18 no.3
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• pp.167-177
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• 2014

New technologies for water purification are continuously emerging to address global water quality problems, and one such technology involves advanced hermetic water purification facilities made by concrete that utilize ozone treatment processes. Better knowledge about surface deterioration of epoxy coating exposed to ozone treatment is needed as a foundation for development of improved methods and materials in the future. This study utilized atomic force microscopy (AFM), nanoindentation methods, and existing indirect methods such as visual observation, changes in mass, surface observation and chrominance analysis, to evaluate epoxy water-resistance and anti-corrosiveness. This study considered six different epoxy formulations to assess typical degradation characteristics of epoxy surfaces with regard to water-resistance/anti-corrosiveness. AFM and nanoindentation techniques emerged as promising direct methods with potential to provide quantitative measures of surface quality that are improvements upon existing indirect methods. The experiments also confirmed that some of the epoxy-coatings were severely iMPacted by ozone exposure, and thus the results demonstrate that concern about such deterioration is justified.

• Child Health Nursing Research
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• v.8 no.3
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• pp.344-356
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• 2002

This study was conducted to analyse the current clinical education of pediatric nursing in baccalaurate nursing program, then to give basic data for enhancing the quality of future clinical education of pediatric nursing. Data were collected through self-reported questionnaire by mail from December 2001 to February 2002. The subjects were 29 schools of 50 baccalaurate nursing education programs. The data were analysed by double raters, researcher and assistant researcher. The results were summarized as follows: 1. Twenty-eight schools had the objectives of the clinical education of pediatric nursing, and 28 schools in pediatric ward, 23 schools in nursery, 22 schools in neonatal intensive care unit(NICU), 15 schools in objectives related to profession by clinical site. 2. Credits on clinical education of pediatric nursing were most 15 schools of 3 credits. 3. The clinical sites were mainly the hospital that sick children were admitted in. 4. The clinical teacher were 9 types including pediatric professor and field nurse. 5. On teacher's role, the professor instructed the case study and conference, and field nurse instructed the patient assignment and nursing procedures. 6. All of schools used explanation and conference as a method of clinical education, 1 or 2 schools used PBL or role play or field study. 7. On clinical education content, most of school included Apgar scoring system, physical examination in newborn assessment, respira- tion maintenance, temperature maintenance, infection prevention, nutrition, and bath in newborn care. 8. On clinical education content, most of school included care of incubator, phototheraty, infusion, gavage feeding and how to use the instruments in NICU. Eighteen schools included attachment promotion, and 20 schools case study. 9. On clinical education content, most of school included a checklist of nursing procedures, case study, assessment of growth and development in pediatric ward and other sites. 10.There were various evaluation types in scores, measuring items. In conclusion, the results of this study revealed that there were some discrepancy in the objectives and contents, clinical sites on hospital focused, teacher's role, and diversity of measurement items and ratings in clinical education of pediatric nursing. There is a need for a standardization of content, clinical site, and evaluation tool to improve a quality of clinical education of pediatric nursing based on this study.