• Korean Journal of Construction Engineering and Management
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• v.17 no.5
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• pp.71-77
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• 2016

Solar energy is a viable source to replace fossil fuels. However, challenges associated with site selection for solar panel installation inhibit the uptake of solar energy systems. Expressway slopes offer a potentially attractive alternative for solar panel installation for the following reasons: expressway slopes are vacant public sites, they are abundant (about 4,193km in South Korea), and they are linear in nature. Traditoinally when selecting sites for solar systems conventional surveying methods are employed. Unfortunately, these methods can be dangerous, time consuming, and labor intensive. To overcome these limitations of conventional site selection methodologies, we propose an automated approach using numerical maps. First, contour and expressway polylines are extracted separately from numeric maps. The extracted contour lines are then converted into a digital terrain model; this is used to calculate aspect and slope information. Next, the extracted expressway lines are projected onto a binary image and refined to recover the disconnections, and then applied to create a buffer zone to narrow the search space. Finally, all data sets are overlaid to identify candidate sites for solar panel systems and are visually verified through comparisons with aerial photos.

• Journal of the Korea Society of Computer and Information
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• v.13 no.7
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• pp.29-36
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• 2008

This paper proposes algorithm for the system that can search for an image of a frame unit, and we implement it. A system already inserts in images after generating the cord that mechanical decoding and identification are possible. We are independent of an external noise in a frame unit, and a system to propose at these papers can search for an image recorded by search condition to include recording date, recording time, a recording place or filming course etc. This system is composed by image insertion wealth to insert data to an image to data image code generation wealth, a frame generating data image code you apply a code generation rule to be fixed in order to express to a price to have continued like data entry wealth, GPS locator values and direction price receiving an image signal, image decoding signals and an image search signal to include search condition, and to have continuity from users each of an image. Also, image decoding we decipher about the noise that was already added from the outsides in a telerecording process, a copy process or storage processes inserted in images by real time, and searching image information by search condition. Consequently we implement decoder, and provide the early system that you use, and we easily insert data code among images. and we can search. and maximization can get precision regarding an image search and use satisfaction as we use algorithm to propose at these papers.

• Journal of Dental Rehabilitation and Applied Science
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• v.28 no.4
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• pp.385-395
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• 2012

This clinical report presents the case using overlay dentures to treat a patient with cleft lip and palate and malocclusion. This patient requires vigorous treatment such as orthodontic treatment and combined orthodontic/oral surgery procedures. Overlay denture can be used as an alternative treatment option. Intraoral and radiographic examinations were done. The vertical dimension of occlusion was evaluated for proper prosthetic procedures and the surveying in the diagnostic cast was done. Considering the tissue and teeth undercut, the alterations of teeth shape were done. Final preparation and impression was performed. After the evaluation of vertical dimension and occlusion with wax-denture, the dentures were polymerized. Clinical remounting and occlusal adjustment were done on the articulator. Overlay dentures were delivered and the patient was recalled for relining. The overlay dentures satisfied patient's esthetic and functional requirements and provided a stable occlusion. Overlay dentures in this case were a reversible and relatively inexpensive treatment for this patient, however the potential possibilities of caries and periodontal disease as a result of poor oral hygiene should be prevented with periodic recall.

• Korean Journal of Construction Engineering and Management
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• v.20 no.6
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• pp.57-65
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• 2019

If aging apartments are left unimproved through remodeling, the city will be eventually slum. As the government recognizes remodeling as an alternative to reconstruction, the law has been revised mainly to increase the housing area, increase the number of house and allow the vertical extension for making remodeling costs. However, the remodeling is still not activated yet in the market. Therefore, this study analyzes the decision factors of apartment remodeling in Seoul metropolitan area based on Heckman two-stage analysis considering sampling error. Research findings indicate that the decision for remodeling is determined by the characteristics of the household, housing, and time-lapse variables. And also the number of household members, net assets, housing satisfaction, the 11-20, 21-30, and more than 30 years of building are identified as the significant variables as a result of remodeling choice probability analysis. It is noteworthy that the significant variables from then remodeling cost analysis are net assets, area, more than 30 years of building, and unit housing price. It is also notable that the policy, which extend the housing area to cover remodeling cost, are not actually effective to activate the remodeling, and the age in the case of elderly people in Seoul and Gyeonggi-do who are expected to have high net assets and income is not significant variables. This study is expected to provide more objective and reliable implication to the policy makers, the home owner and the investors on the decision making process related to the remodeling project.

• Proceedings of the Korea Water Resources Association Conference
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• 2019.05a
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• pp.56-56
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• 2019

우리나라는 최근 기후변화로 인하여 가뭄의 빈도와 강도가 점점 증가하고 있는 추세이며, 이에 따른 농업가뭄 현상은 매년 발생하고 있는 실정이다. 2000년 이후부터 무상으로 공급되고 있는 농업용수에 대해 농민 물이용 손실을 저감하고, 물부족에 대비한 선제적인 가뭄대응의 일환으로 물절약 교육 및 홍보를 통한 농민 물절약의 중요성 인식으로 2015년에 "농업농촌부문 가뭄대응 종합대책"에 농민 절수교육 및 홍보를 통한 물절약 추진 과제가 포함되었다. 농민 물절약 교육을 통한 농민의 가뭄에 대한 경각심과 물절약 실천의 중요성을 인식시키고, 농업인의 자발적인 물절약 실천을 통한 효율적 수자원 이용을 도모하는데 그 의의가 있다. 이에 따라 2016년 농민 물절약교육 모델이 개발되었으며, 2017년에는 물절약 교육 모델의 현장적용을 위한 시범교육이 실시되었다. 또한 "2018년 정부 가뭄종합대책" 중 가뭄대책 실천의 일환으로 물절약 교육 및 홍보실시 확대 추진을 위해 2018년도에는 2016년과 2017년에 실시한 농민 물절약 시범교육을 바탕으로 물절약 교육 모델의 실용화를 위한 농민 물절약 교육 전문인력 양성을 실시하였다. 본 연구에서 진행한 물절약 교육 전문인력 양성 프로그램은 농업용수의 물공급 및 관리기관인 한국농어촌공사 지사단위 유지관리 직원을 대상으로 하였으며, 전국적으로 경기 강원권, 충청권, 호남권, 경상 제주권의 4개 권역으로 나누어 상 하반기 교육을 실시하여 총 322명의 교육인력을 양성하였다. 전문인력양성 교육은 물절약 교육에 대한 전반적인 이해와 현장적용을 위해 농민 물절약 교육 이수단계별교육 내용 및 교육 방법을 이해하고, 각 단계별 교육을 직접 실습해 보는 시간으로 구성하였다. 교육 이수 후에는 교육생의 학습에 대한 이해도 및 교육 만족도를 조사하고 기타 교육에 대한 의견수렴을 위해 설문조사를 실시하였다. 그 결과, 교육생의 대부분이 농민 대상 물절약 교육의 필요성을 매우 공감하는 것으로 나타났으며, 물절약 교육의 지속적인 실천 및 전국적인 확대를 위해 별도의 예산 및 인력지원의 필요성을 강조하였다. 교육과정을 완료 후에는 수료증을 수여하였으며, 본 연구에서 개발한 물절약 교육의 현장적용을 위한 물절약 교육 강사용 교재를 배포함으로 본 교육을 이수한 전문인력의 농민 물절약 교육에 활용하도록 하였다.

• Journal of the Korea institute for structural maintenance and inspection
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• v.25 no.4
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• pp.75-82
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• 2021

The objective of this study is to examine the loss of prestressing stress in the developed prestressing reinforcing units using steel bar and pipe (SP). The main parameters were the reinforcing bar type, the magnitude of prestressed force, and prestressing method. The test results showed that the loss of prestressing stress for SP was highest in the initial prestressing step, which was higher for the compression introduction typed specimens than tension introduction typed specimens. The loss of prestressing stress of SP made with P800 was 1.6% for the compression introduction typed specimen with 0.8f_y, which was lowest than the other specimens. Meanwhile, the relaxation of SP with the respect to the time ranged between 0.4 and 1.9%, irrespective of SP material type, the magnitude of prestressed force, and prestressing method. These values were less than 2.5%, which is the maximum value for the relaxation of prestressed reinforcing steel bars in design codes. Consequently, considering the loss of stress developed in the initial prestressing step, the developed SP material type, prestressing introduction method, and magnitude are recommended to be P800, compression introduction type, and 0.8f_y.

• Journal of the Korea institute for structural maintenance and inspection
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• v.23 no.2
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• pp.116-121
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• 2019

In order to evaluating applicability of RAP (recycled aggregate powder) in mortar, in this study, physical and mechanical tests was carried out. Material characteristics of recycled aggregate and RAP were evaluated and the mechanical properties of mortar replaced with RAP were analyzed. Test result of sieve analysis showed that as the milling time increased the fineness modulus was decreased and the distribution of 0.6 mm particle size was found to increase. The fluidity of mortar mixture substituted with RAP tended to increase than Plain mixture. It was result that the increasing fluidity was affected by unreacted surplus water in the mortar as the binder was replaced with RAP. From the compressive strength result of the mortar subjected to RAP, it was found that the RAP was able to replace up to about 10% of unit binder weight although the compressive strength of mortar was decreased as the RAP replacement increased. From the above study, it can be concluded that the physical properties of RAP satisfied the quality standard of aggregate for replacement with fine aggregate. Moreover, in case of the RAP was replaced up to 10% of unit cement weight, it was able to be possible to improve fluidity and compressive strength of mortar.

• Journal of the Korea institute for structural maintenance and inspection
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• v.26 no.6
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• pp.139-147
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• 2022

In this study, we designed a high-strength, low-alkali type cement composite for artificial reef by mixing various binders and evaluated whether it is possible to manufacture it with an ME method 3D printer. As a result of the tests, it is found that it is important to control the water-binder ratio, the silica sand-binder ratio, and the type of silica sand in order to control the fluidity of the cement composites to enable 3D printing. The surface quality of 3D printer output can be achieved by adjusting the amount of viscosity agent added while obtaining printable fluidity. In the cement composites mixing proportion using the alpha-type hemihydrate gypsum, a setting control agent needs to be used to control the quick setting effect. It is also necessary to derive the time to maintain the fluidity, and to apply it when printing. To obtain the required strength, the mix proportion needs to be modified while satisfying the fluidity level of 3D-printable cement composites. In the present study, 3D-printable mix proportions were designed by the use of multi-component binders including alpha-type hemihydrate gypsum a for low-alkali type artificial reefs, and the printability was confirmed. A further study needs to be performed to quantitatively evaluate the alkali reduction effect.

• The korean journal of orthodontics
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• v.27 no.6 s.65
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• pp.979-995
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• 1997

The purpose of this study was to identify the preventive and the progressive inhibitory effects of enamel demineralization with fluoride releasing light-and self-cured orthodontic sealants(FluoroBond), in vitro, under the polarizing light microscope and the scanning electon microscope. The polarizing light microscopic group was subdivided into seven groups(Group A-Group G). The scanning electron microscopic group was also subdivided into seven groups(Group A'-Goup G'). For polarizing light microscopic evaluation, longitudinal sections were made longitudinally by Maruto cutter(Maruto Co., Japan) and Maruto grinding machine(Maruto Co., Japan). Sections were examined and photographed by the polarizing light microscope(Olympus Optical Co., Japan) using crossed polars and with the enamel rod longitudinal axis oriented at $45^{\circ}$ to the extinction position. For scanning electron microscopic evaluation, the specimens were coated with a highly conducting layer of gold palladium in a model Hus-4 high-vacuum evaporator and examined in an ISI-100B scanning electron microcope operated at 20kV. The results of this study were as follows : 1. The mean depths of artificial carious lesions under a polarized light microscope were $Group\;A(5.08{\mu}m),\;Group\;B(47.82{\mu}m,\;Group\;C(8.42{\mu}m),\;Group\;D(7.20{\mu}m),\;Group\;E(85.41{\mu}m),\;Group\;F(60.38{\mu}m),\;Group\;G(60.13{\mu}m)$. 2. There were statistically significant differences in Group B compared with Group A, C, and D(p<0.05), and also, in Group I compared with Group F and Group G(p<0.05). 3. Light-and self-cured orthodontic sealants had the preventive effects of enamel demineralization. 4. Light-and self-cured orthodontic sealants had the progressive inhibitory effects of enamel demineralization. 5. The time progress of demineralizing agent had no influence on the samples of light-and self-cured orthodontic sealants under the scanning electron microscope. 6. There was no difference between the specimens of light-and self-cured orthodontic sealants both in the polarized light microscopic group and in the scanning electron microscopic group.

• The Journal of the Korea Contents Association
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• v.17 no.12
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• pp.461-472
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• 2017

The purpose of this study is to analyze the current status and condition of children's playgrounds in K which parents recognize as in Gyeonggi-do and provide basic data for the qualitative environment for daily outdoor play of young Children. To do so, a survey of 269 parents living in Gyeonggi-do was conducted and reconstructed based on the advanced research related to outdoor play. Also it was evaluated and revised after consultation with 3 children education specialists. The repossessed questionaries were frequency-analyzed with SPSS 20.0 program. The result of the analysis on outdoor playgrounds is in the following. First of all, it was analyzed that parents required 1 or 2 hours for their children to play outdoors in a type of "forest playgrounds." Moreover, they said that it was really important for the children to feel "interesting and funny" during the outdoor play, and they recognized that the play would be helpful for the children's socialization. However, they felt that a risk factor of the outdoor play was "a vehicle risk in streets." Secondly, the study suggested that there were outdoor playgrounds around parents' houses, and a type of the outdoor play was "a playground installed in the apartment complex." Furthermore, most of the parents weren't satisfied with the outdoor play because the apartment neglected the management of the playgrounds, and there were no playing facilities that were good enough to derive children's curiosity and adventurous spirit. The result also showed that most of the children played outdoors with "their mothers," and they participated in indoor activities, especially playing a game or watching TV rather than outdoor activities after attending a children educational institute. Lastly, when it comes to areas of outdoor play to be improved, it was necessary to "expand playgrounds that children can use for each season," build "safe playgrounds" for a type of the outdoor play," provide "playing spaces" for a spatial type, and "control vehicles around the playgrounds and deal with dangerous things" to prevent safety accidents. The result can expand the understanding of outdoor play for Young Children and offer discussions about the relevant organizations and studies.