• Restorative Dentistry and Endodontics
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• v.44 no.2
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• pp.21.1-21.8
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• 2019

Objectives: The purpose of the present study was to evaluate the effect of calcium hydroxide with 2% chlorhexidine gel (HCX) or distilled water (HCA) compared to triple antibiotic paste (TAP) on push-out bond strength and the cement/dentin interface in canals sealed with White MTA Angelus (WMTA) or Biodentine (BD). Materials and Methods: A total of 70 extracted human lower premolars were endodontically prepared and randomly divided into 4 groups according to the intracanal medication, as follows: group 1, HCX; group 2, TAP; group 3, HCA; and group 4, control (without intracanal medication). After 7 days, the medications were removed and the cervical third of the specimens was sectioned into five 1-mm sections. The sections were then sealed with WMTA or BD as a reparative material. After 7 days in 100% humidity, a push-out bond strength test was performed. Elemental analysis was performed at the interface, using energy-dispersive spectroscopy. The data were statistically analyzed using analysis of variance and the Tukey test (p < 0.05). Results: BD presented a higher bond strength than WMTA (p < 0.05). BD or WMTA in canals treated with calcium hydroxide intracanal medications had the highest bond strength values, with a statistically significant difference compared to TAP in the WMTA group (p < 0.05). There were small amounts of phosphorus in samples exposed to triple antibiotic paste, regardless of the coronal sealing. Conclusions: The use of intracanal medications did not affect the bond strength of WMTA and BD, except when TAP was used with WMTA.

• Journal of the Korean School Mathematics Society
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• v.17 no.1
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• pp.123-137
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• 2014

In this paper, the format of the Korean 2011 & the Japan 2008 elementary school mathematics curriculum are compared especially centered on elements, areas, objectives, and lesson time numbers. Through this comparison, suggestions can be obtained as follows. First, grade-group system which does not meet the actual elementary mathematics education needs to be reconsidered. Second, the area name 'number and operation' needs to be reduced into the area name 'number and calculation'. Third, using the area name 'pattern' needs to be reconsidered. Fourth, using the area name 'probability' needs to be reconsidered. If 'possibility' which some event occurs is seen as ratio, it can be contained area 'quantity relationship'. Fifth, containing the nature of mathematics into the school mathematics objectives needs to be reconsidered. Sixth, it is necessary to enhance the phase of mathematics in elementary education.

• Journal of the Korean Institute of Rural Architecture
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• v.9 no.2
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• pp.29-40
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• 2007

The purpose of this study is to clarify the actual conditions of external space of middle and high schools in Gyeongnam Area. This article discuses about the characteristics of the external space and the site plan type of 49 middle and high schools in Gyeongnam Area. The result of analysis about site plan type, composition state of external space and area ratio of its composition of each middle and high school facilities are as follows: In facilities arrangement of middle and high schools, it shows diverse forms of arrangement from existing uniform straight type, however, most of schools do not being against the simple in their external space. Especially, for the area is small in the composition of external space, a playground is only under $50m{\times}80m$ and outdoor learning space or resting space is not secured sufficiently. Therefore, it requires an expansion of space size and facilities for the change of school life outside class.

• Journal of the Korean Society of School Health
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• v.4 no.1
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• pp.100-115
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• 1991

The purpose of this study is to provide the necessary data for the effective performance of school nurse's work by comparing with the recognition and expectation on school nurse's work by the students and their teachers in school settings. The sample of this study was consisted of the 441 students and 535 teachers in Suwon. The data were collected by means of a structured questionnaire from 24th, Sept, to 29th, Sept. 1990. The collected data were analyzed utilizing SAS/PC program for percentage, frequency, mean, standard deviation and chisquare test. The major findings of this study were as follows: 1. The result of analysis in recognition on school nurse's work. There is no statistically significant difference 'depending on teachers' school level, sex, age and career with school nurse(P>0.05). The students show significant difference on their school level and sex(P>0.05). Also, in the areas of school nurse's work, school clinic management has the highest recognition and school environment management has the lowest recognition. 2. The result of analysis in expectation on school nurse's work. There is statistically significant difference depending on teachers' and students' school level: the order of expectation is elementary, middle, and high school(P<0.05). In the result of comparison with students' and teachers' expectation in the same school level, there is significant difference only in elementary school(P<0.05). However, there is no statistically significant difference depending on teachers' sex, age, career with school nurse and students' sex(P>0.05). Also, in the areas of school nurse's work, school clinic management has the highest expectation and school environment management has the lowest expectation. Synthesizing the result of the study, we can have the conclusion like following. First, students' recognition on school nurse's work is lower than teachers' because most of school nurse's work is performed through their homeroom teachers or other teachers. That can be the limitation for students to recognize school nurse's work. So, there must be a chance of regular meeting between school nurse and students to perform school nurse's work effectively. For this. we must change our educational system and make school nurse charge regular lesson. Second, in each area of school nurse's work, both students' and teachers' recognition and expectation about the area of school environment management has much lower score than the other areas. This indirectly shows the school nurse don't do the work of the area actively. So, school nurses must make an effort to do the work of the area actively. And we must enforce the education of this area in education for new school nurses or re-education for school nurses.

• Journal of the Korean Institute of Landscape Architecture International Edition
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• no.1
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• pp.67-74
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• 2001

Now that importance of landscape planning unique to each area is emphasized, it is necessary to conduct landscape planning by taking advantage of natural environments unique to each ares, because its natural environments are regarded as one of the assets the area possesses. This study targets at Kawachinagano City, Osaka, one of the residential areas that I not only rich in natural and historical elements, but also has been rapidly growing. The purposes of this study are to evaluate change in landscape structure over time by analyzing relation between landform and pattern of expanding the built-up area at three time points of 1932, 1967, and 1994 with GIS (ARC/INFO 7.0.3, ARC/View 3.0 (ESRI)), as well as to make some suggestions for planning landscape unique to the area. Data on main ridges, sub ridges, main rivers, and other landform were read from the elevation map, and data on woodland, and parks and open spaces (having more than 3 ha area) were read from the existing land use map. The data were used to understand the natural structure of the city from topographic viewpoint. Next, the existing land use map prepared with data on the built-up area and urban axes consisting of roads and streets were overlaid on the elevation map in order to understand relation between pattern of expanding the built-up area and the natural structure.

• Journal of Korean Dental Science
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• v.3 no.2
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• pp.4-11
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• 2010

Purpose: This study aimed at examining the thickness of lateral cortical bone in the mandibular posterior body and the location of the inferior alveolar nerve canal as well as investigating the clinically viable bone grafting site(s) and proper thickness of the bone grafts. Subjects and Methods: The study enrolled a total of 49 patients who visited the Department of Oral and Maxillofacial Surgery at Kyung Hee University Dental Hospital to have their lower third molar extracted and received cone beam computed tomography (CBCT) examinations. Their CBCT data were used for the study. The thickness of lateral cortical bone and the location of inferior alveolar nerve canal were each measured from the buccal midpoint of the patients' lower first molar to the mandibular ramus area in the occlusal plane of the molar area. Results: Except in the external oblique ridge and alveolar ridge, all measured areas exhibited the greatest cortical bone thickness near the lower second molar area and the smallest cortical bone thickness in the retromolar area. The inferior alveolar nerve canal was found to be located in the innermost site near the lower second molar area compared to other areas. In addition, the greatest thickness of the trabecular bone was found between the inferior alveolar nerve canal and the lateral cortical bone. Conclusions: In actual clinical settings involving bone harvesting in the posterior mandibular body, clinicians are advised to avoid locating the osteotomy line in the retromolar area to help protect the inferior alveolar nerve canal from damage. Harvesting the bone near the lower second molar area is judged to be the proper way of securing cortical bone with the greatest thickness.

• Korean Journal of Organic Agriculture
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• v.21 no.4
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• pp.539-554
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• 2013

This study analyses the factors that affect the satisfaction of school meals program. To obtain the data, 54 elementary, middle and high schools in Jeonbuk area were chosen for survey. A ordered probit model analysis is conducted to identify the key explanatory variables that affect the satisfaction of school meals about elementary, middle and high school's students. Also, a ordered probit model is used to calculate marginal effects of several key variables. The study finds that key factors that affect to increase the satisfaction of school meals are rural area schools, elementary school's students, and education for school meals or food nutrition. The satisfaction of school meals in urban and rural school's students are significantly different. Also, the satisfaction of school meals about elementary, middle and high school's students are significantly different. To do this, importance of school meals is to build up the safe agricultural supply system. For safe agricultural supply system, local agricultural products provided in school meals should be supplied based on GAP, HACCP certificated companies such as US FTS(Farm to School) program.

• Journal of the korean academy of Pediatric Dentistry
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• v.38 no.2
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• pp.109-118
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• 2011

The aims of this study were analyze the amount of stress condition when the traction force was applied to the condyle head from the chin area of mandible and amount of distortion condition when intended 0.5 mm distraction distance from surface or one point of dissected midline of mandible. For this study, 3D finite element analysis were performed. The following results were obtained : 1. When traction force of 500 g was applied to the condyle head from the chin area, condylar neck area showed the greatest amount of stress and coronoid process was the least amount of stress area. For the amount of distortion condition, infra dental area showed the greatest. 2. When 0.5 mm of intended surface distortion was applied after dissection of mid-mandible area, base anterior area showed the greatest amount of stress but the least stress area was coronoid process. For the amount of distortion, infra dental, menton area showed the greatest amount. 3. One point distortion was applied after dissection of mid-mandible area, ramus posterior area showed the greatest amount of stress and menton area were the least stress condition. For the amount of distortion, menton area showed the greatest amount of distortion condition.

• Journal of the East Asian Society of Dietary Life
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• v.17 no.4
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• pp.597-606
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• 2007

The purpose of this study was to investigate the satisfaction with school foodservice programs by foodservice operation type in middle school and high school students in the Geumsan-Gun area. A total of 530 subjects(250 middle school and 280 high school students) from the Geumsan-Gun area participated from March 15 to March 23, 2004. Questionnaires were used to study dietary habits, activity levels, and current health conditions. The results of the study are summarized as follows. Based on the body mass index(BMI) scores of the students, the high school male BMI scores were significantly different(5%), and they were underweight for their height. The students were primarily dissatisfied with times for meals for school foodservice under direct management and with the quantity of meal for school foodservice under contract. Compared to the middle school female students, the male high school students were dissatisfied with the time for meals and quantity of food. Generally, the students were satisfied with dessert items the most. The food most often wasted was soup. The middle and high school students preferred food services to those under contract.

• Steel and Composite Structures
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• v.48 no.1
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• pp.27-41
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• 2023

Under the long-term effect of corrosive environment, many cold-formed steel (CFS) structures have serious corrosion problems. Corrosion leads to the change of surface morphology and the loss of section thickness, which results in the change of instability mode and failure mechanism of CFS structure. This paper mainly investigates the elastic local buckling behavior of corroded CFS columns. The surface morphology scanning test was carried out for eight CFS columns accelerated corrosion by the outdoor periodic spray test. The thin shell finite element (FE) eigen-buckling analysis was also carried out to reveal the influence of corrosion surface characteristics, corrosion depth, corrosion location and corrosion area on the elastic local buckling behaviour of the plates with four simply supported edges. The accuracy of the proposed formulas for calculating the elastic local buckling stress of the corroded plates and columns was assessed through extensive parameter studies. The results indicated that for the plates considering corrosion surface characteristics, the maximum deformation area of local buckling was located at the plates with the minimum average section area. For the plates with localized corrosion, the main buckling shape of the plates changed from one half-wave to two half-wave with the increase in corrosion area length. The elastic local buckling stress decreased gradually with the increase in corrosion area width and length. In addition, the elastic local buckling stress decreased slowly when corrosion area thickness was relatively large, and then tends to accelerate with the reduction in corrosion area thickness. The distance from the corrosion area to the transverse and longitudinal centerline of the plate had little effect on the elastic local buckling stress. Finally, the calculation formula of the elastic local buckling stress of the corroded plates and CFS columns was proposed.