• Structural Engineering and Mechanics
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• v.77 no.1
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• pp.1-17
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• 2021

The influence of prestress force on the fundamental frequency and static deflection shape of uncracked Prestressed Concrete (PC) beams with a parabolic bonded tendon was examined in this paper. Due to the conflicts among existing theories, the analytical solutions for properly considering the dynamic and static behavior of these members is not straightforward. A series of experiments were conducted for a total period of approximately 2.5 months on a PC beam made with high strength concrete, subsequently and closely to the 28 days of age of concrete. Specifically, the simply supported PC member was short term subjected to free transverse vibration and three-point bending tests during its early-age. Subsequently, the experimental data were compared with a model that describes the dynamic behavior of PC girders as a combination of two substructures interconnected, i.e., a compressed Euler-Bernoulli beam and a tensioned parabolic cable. It was established that the fundamental frequency of uncracked PC beams with a parabolic bonded tendon is sensitive to the variation of the initial elastic modulus of concrete in the early-age curing. Furthermore, the small variation in experimental frequency with time makes doubtful its use in inverse problem identifications. Conversely, the relationship between prestress force and static deflection shape is well described by the magnification factor formula of the "compression-softening" theory by assuming the variation of the chord elastic modulus of concrete with time.

• Korean Journal of Human Ecology
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• v.20 no.3
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• pp.505-519
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• 2011

The purpose of this study was to analyze the relationship between organizational commitment, organizational loyalty, and working satisfaction of 162 teachers in daycare centers in Gyung-gi province. Three questionnaires about the organizational commitment which Allen and Mayer(1990) developed and Son Sobin(2002) revised, organizational loyalty behavior which Jo Bumsang(2004) revised, and working satisfaction which Kim Sunja(2005) developed, and the researcher revised were used for this study. For this study, the data was analyzed using descriptive statistics, independent t-test, and Pearson correlation. The results were as follows: first, the early childhood teacher's organizational commitment was average, and there was a significant difference according to the teacher's academic background. Second, the early childhood teacher's organizational loyalty was also average, and there were significant differences according to the teacher's age and academic background. Third, the early childhood teacher's working satisfaction was below average level, and there was a significant difference according to the teacher's working hours. Last, the early childhood teacher's organizational commitment, organizational loyalty behavior, and working satisfaction showed the positive relationship. In conclusion, the government and the director of daycare centers should support for the teacher's psychological satisfaction because the early childhood teacher's psychological state is highly related to successful organization of daycare centers.

• Women's Health Nursing
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• v.11 no.1
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• pp.46-51
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• 2005

Purpose: The aim of this study was to identify risk factors for breast cancer and early screening behavior in women in the community. Method: The participants were 125 women residing in W city. Data was collected using an instrument developed by the researchers. Analysis was done using descriptive statistics, and the $x^2$ test. Result: For risk based on the Gail Model, age (above 50 years) had a distribution of 24.8%, first degree family history, 4.9%, age at first full term pregnancy, 13.8%, and benign breast cancer history, 4.9%. For risk based on other common risk factors, menopause had a distribution of 20.7%, did not breast feed, 15.4%, history of HRT, 7.3%, meat preference, 35.0%, and history of smoking or drinking, 2.4% and 43.5%, respectively. There was a significant difference in BSE and mammography screening behavior ($x^2=22.5$, p<.00), but no difference in distribution of risk factors and screening behavior. Conclusion: For effective prevention of breast cancer, it is necessary to develop an instrument for risk assessment and, through assessment, select women at high risk. It is also necessary to provide education and appropriate recommendations on screening behavior.

• Women's Health Nursing
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• v.16 no.2
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• pp.126-136
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• 2010

Purpose: This study was done to evaluate factors affecting active early detection behaviors of breast cancer and performance rate of breast self examination (BSE), physical examination and mammography. Methods: The participants were 264 women from an outpatient breast clinic of a university hospital and materials were collected from March 2007 to February 2008 using a structured questionnaire. The data were analyzed using $x^2$ test, logistic analysis. Results: The rate for BSE was 58.3%, for physical examination, 55.3% and for mammography experience, 63.4%. Women with all of these active early detection behaviors accounted for 31.8% of the participants. Various factors such as age, income, marital status, and menopause showed increased significant performance rate. The explanation power of logistic model was 48.5%, and was significant for age, income and health belief. Factors related to high performance rate were being over 40 years of age, high income and high health belief score. Conclusion: Active early detection behaviors were not high in spite of marked increases in breast cancer incidence. Encouragement for women practicing early detection behavior is important, but there is also a need to develop interest and support for the low performance group. More sustained education and public relations are needed to further improve active early detection behavior.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.6
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• pp.2501-2505
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• 2015

Purpose: The present study was carried out to measure knowledge level and behavior of family health personnel (FHP) in Izmir on early diagnosis of breast and cervical cancers. Materials and Methods: The study population of this cross-sectional study was not selected. A questionnaire was applied to all FHP to measure knowledge level and behavior about cancer. The participation rate was 88%. Breast examination, mammography analysis, Papanicolaou smear applications were determined as dependent variables, and knowledge level about breast and cervical cancer, age, professional time as FHP as independent variables. Data were evaluated using definitive statistics, chi-square and logistic regression tests in SPSS software package for Windows 15.0. Results: A total of 970 family health personnel participated in the research. The age range was 20-45 years (82.4%). Mean age was $37.9{\pm}7.4$. Response rate was 87.3%. Of the participants, 88.4% performed breast self-examination. Rate of performing mammography at least once was 24.1%. Rate of performing Pap-smear examination at least once was 61.0%. In logistic regression analyses, it was determined that people with knowledge on breast and cervical cancer were those performing breast self-examination, mammography and Pap-smear examinations (p<0.05. Conclusions: It is essential that the knowledge, behavior and manners of health providers on early diagnosis for cancer increases awareness in the general population and provides information on execution ofthe most effective methods for generating a healthy society.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.22 no.1
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• pp.41-49
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• 2019

Recent studies on pediatric inflammatory bowel disease (IBD) have revealed that early-onset IBD has distinct phenotypic differences compared with adult-onset IBD. In particular, very early-onset IBD (VEO-IBD) differs in many aspects, including the disease type, location of the lesions, disease behavior, and genetically attributable risks. Several genetic defects that disturb intestinal epithelial barrier function or affect immune function have been noted in these patients from the young age groups. In incidence of pediatric IBD in Korea has been increasing since the early 2000s. Neonatal or infantile-onset IBD develops in less than 1% of pediatric patients. Children with "neonatal IBD" or "infantile-onset IBD" have higher rates of affected first-degree relatives, severe disease course, and a high rate of resistance to immunosuppressive treatment. The suspicion of a monogenic cause of VEO-IBD was first confirmed by the discovery of mutations in the genes encoding the interleukin 10 (IL-10) receptors that cause impaired IL-10 signaling. Patients with such mutations typically presented with perianal fistulae, shows a poor response to medical management, and require early surgical interventions in the first year of life. To date, 60 monogenic defects have been identified in children with IBD-like phenotypes. The majority of monogenic defects presents before 6 years of age, and many present before 1 year of age. Next generation sequencing could become an important diagnostic tool in children with suspected genetic defects especially in children with VEO-IBD with severe disease phenotypes. VEO-IBD is a phenotypically and genetically distinct disease entity from adult-onset or older pediatric IBD.

• Proceedings of the Korea Concrete Institute Conference
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• 1999.04a
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• pp.361-366
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• 1999

The purpose of this study is to evaluate the structural performance of Reinforced steel fiber concrete structures using early age concrete. Reinforced concrete structures using early age concrete are result in the degradation of structural performance due to crack, overload, unexpected vibration and impact load. Specimens, designed by the over 0.75% of steel fiber incorporated, were showed the ductile behavior and failed slowly with flexure and flexure-shear. Increasing the percent of steel fiber incorporated(0.25~2.0%), the ultimate shear stress of each specimen were increased 12~40% than that of specimen SSS.

• Proceedings of the Korea Concrete Institute Conference
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• 2009.05a
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• pp.89-90
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• 2009

FBG temperature sensor and strain sensor has been used to monitoring shrinkage and temperature of concrete retaining wall in construction site in its casting early age. The test results indicate that this monitoring method is a practical method for monitoring concrete at very early age. The monitoring technique used in this research could be extended to monitor shrinkage and temperature for mass concrete structure.

• Proceedings of the Korea Concrete Institute Conference
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• 2003.05a
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• pp.427-432
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• 2003

An analytical method to predict the flexural behavior of composite girder is presented in which the early-age properties of concrete are specified including maturing of elastic modulus, creep and shrinkage. The time dependent constitutive relation accounting for the early-age concrete properties is derived in an incremental format by expanding the total form of stress-strain relation by the first order Taylor series with respect to the reference time. The sectional analysis calculates the axial and curvature strains based on the force and moment equilibriums. The deflection curve of the box girder approximated by the quadratic polynomial function is calculated by applying to the proper boundary conditions in the consecutive segments. Numerical applications are made for the 3-span double composite steel box girders which is a composite bridge girder filled with concrete at the bottom of the steel box in the negative moment region. The one dimensional finite element analysis results are compared with those of the three dimensional finite element analysis and the analytical method based on the sectional analysis. Close agreement is observed among the three methods.

• International Journal of Highway Engineering
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• v.6 no.2 s.20
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• pp.47-59
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• 2004

The temperature variation of concrete pavement at early-age significantly affects the initiation and propagation of its early-age cracks. This implies that the measurement and analysis of early age temperature trend are necessary to examine the causes of early age cracks in the concrete pavement. In this study, it is investigated how the early age temperature trend in concrete pavement affects the random crack initiation and behaviors of saw-cut joints using the actual construction site which is located at the KHC test road. During 72 hours after placing the concrete pavement, the ambient air temperature and temperatures at the top, middle, and bottom in concrete pavement were measured and the random crack initiation in concrete slabs and early age behaviors in the joints were surveyed. The investigation results indicate that the first random crack was initiated at one of the slabs placed in the early morning which have higher temperature changes during early 72 hours. The movement of slab was influenced by the early-age crack in the joint. It suggested that the different occurrence time of the cracks in the joint had an influence on the behavior of the cracks. Besides, the slab constructed In the morning had higher possibility of crack initiation than that in the afternoon. The rarely occurred cracks had bigger gap than other cracks.