• Korean Journal of Optics and Photonics
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• v.35 no.3
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• pp.95-106
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• 2024

In the 21st century, white light-emitting diodes (LEDs) are widely used as backlighting for liquid crystal displays and as a light source for general illumination. However, white LEDs used in lighting often use a single yellow phosphor on top of a blue LED chip, which lacks the ability to reproduce natural colors in objects under conventional illumination accurately. Recently, researchers have been actively working on realizing high color-rendering lighting by incorporating red quantum dots to improve the spectrum in the long-wavelength band, which is deficient in conventional white LEDs. In particular, how to develop and apply remote quantum dot components to ensure long-term reliability is currently under active research. This paper introduces recent research on remote quantum dot components and the current status of developing high color-rendering lightings with them. Especially, we focus on various factors that are important to consider in optimizing the optical structure of the quantum dot components and discuss the future directions and prospects of research for high color-rendering lighting technology.

• Journal of the Korean Institute of Landscape Architecture
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• v.36 no.6
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• pp.22-33
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• 2009

This study was undertaken to provide a basis for planning trail standards, providing rights of movement, improvement of health and the experience of nature for at-risk walkers for application to the Umyen Park site. This study researched related laws, manuals, scholastic writing and the established site, a raku-raku mountain trail in Osata, Japan. By referencing these results and similar standards, a conceptual trail plan for at-risk walkers was created. The plan suggests five points -- accessibility, convenience, social aspects, economic efficiency, and environmentally-friendliness -- and referenced an evaluation of outdoor living environments for the elderly. The planning standards are comprised of four steps that are ranked in order and are related to the selection of location, trail structure, route patterns, and equipment. Plans for trails catering to at-risk walkers in Umyen Park were then based on these standards. As a result, it was found that the mountain has both a high elevation and abundant natural resource, both of which must be taken into account during planning. This study is valuable because it is one of the first studies of trail plans for at-risk walkers made in mountainous urban parte. Subsequent research can use the standards of this study for further evaluation while future modifications must reflect changing needs and details.

• Korean Journal of Heritage: History & Science
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• v.45 no.4
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• pp.38-53
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• 2012

This paper investigated the construction year of 'Jeongnimsa(定林寺)temple in Buyeo(扶餘) through the recent archaeological records. First, the composition of land for the construction of temple was linked with Gwanbukri(官北里) sites which is estimated as palace. The composition of land for the palace was formed at late 6th century. Second, the several furnace sites was discovered under the foundation soil layers for the construction of temple. Reference to the pottery excavated from the previous surface indicates that the workshops having been operated a period of time after the transfer of the capital to Sabi(泗?). These workshops having been operated before the construction of roof-tile buildings which were followed by the large-scale composition of land for the palace at Gwanbukri sites adjacent to the north of 'Jeongnimsa. The pottery, roof-tiles and chinese porcelain which were included in the earth laid on the ground for the construction of temple also indicates that the construction year of temple do not go up to shortly after the transfer of the capital to Sabi. This is related with that wooden pagoda would have been present before stone pagoda and the foundation of the wooden pagoda would have soared into the ground. Last, the building layout of temple is familiar to Iksan(益山) Mireuksa(彌勒寺址) temple site than the temples of Buyeo such as Wangheungsa(王興寺址) temple site. This imply that Jeongnimsa temple was not constructed shortly after the transfer of the capital to Sabi like the opinion of the existing. Jeongnimsa temple was probably constructed at late 6th century when composition of the Sabi city was actively made.

• 한국지구물리탐사학회:학술대회논문집
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• 1999.08a
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• pp.48-64
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• 1999

For quantitative evaluation of geotechnical engineering properties such as rippability and diggability, clear interpretation on the subsurface velocity structures should be preceded by figuring out top soil, weathered and soft rock layers, shape of basement, fracture zones, geologic boundary and etc. from the seismic refraction data. It is very important to set up suitable field parameters, which are the configuration of profile and its length, spacings of geophones and sources and topographic conditions, for increasing field data quality Geophone spacing of 3 to 5m is recommended in the land slope area for house land development and 5 to 10m in the tunnel site. In refraction tomography technique, the number of source points should be more than a half of available channel number of instrument, which can make topographic effect ignorable. Compared with core logging data, it is shown that the velocity range of the soil is less than 700m/s, weathered rock 700${\~}$1,200m/s, soft rock 1,200${\~}$1,800m/s. And the upper limit of P-wave velocity for rippability is estimated 1,200 to 1,800m/s in land slope area of gneiss. In case of tunnel site, it is recommended in tunnel design and construction to consider that tunnel is in contact with soft rock layer where three lineaments intersecting each other are recognized from the results of the other survey.

• The Journal of Engineering Geology
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• v.11 no.2
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• pp.163-174
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• 2001

For quantitative evaluation of geotechnical engineering properties such as rippability and diggability, clear interpretation on the subsUJiace velocity structures should be preceded by figuring out top soil, weathered and soft rock layers, shape of basement, fracture zones, geologic boundary and etC. from the seismic refraction data. It is very important to set up suitable field parameters, which are the configuration of profile and its length, spacings of geophones and sources and topographic conditions, for increasing field data Quality. Geophone spacing of 3 to 5m is reconunended in the land slope area of house land development site. In refraction tomography technique, the number of source points should be more than a Cluarter of available channel number of instrument and the subsurface structure interpretation can be decreased the artifact of inversion by topographic effect. Compared with core logging data, it is shown that the velocity range of the soil is less than 700m/s, weathered rock 700~1,200m/s, soft rock 1,200~1,800m/s on the velocity tomogram section. And the upper limit of P-wave velocity for rippability is estimated 1,200 to 1,800m/s in land slope area of gneiss.

• The Journal of the Korea Contents Association
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• v.13 no.6
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• pp.370-379
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• 2013

In an effort to resolve the burden of patients hiring patient sitters, this study sought to review the Ministry-of-Health-and-Welfare-initiated pilot program of running hospitals without patient-sitter to identify its background, operation method, performance results, and limitations. Based on the review, the study derived the necessity of introducing a hospital system without patient-sitter as well as its operation and systemization methods. The ministry-initiated pilot programs were conducted twice: in 2007, and in 2010. A review of the 2007 pilot program revealed that the patients and families' satisfaction score with nursing services was 9.1 points (on a 10-point scale), their intention to reuse the service was 97.8%, and their intention to recommend the service was 98.0%, all high scores. Appropriate nursing manpower, derived from the 2007 pilot project, indicated 2.3 patients per nurse and 4.0 patients per nurse aid. The 2010 pilot project results indicated that the patients and families' satisfaction was high at 8.0-9.1 points (on a 10-point scale), and that the intention to reuse and recommend the service was also high. Compared with the 2007 pilot project, however, the types of medical institutions and the nurse to patient ratios were diverse, offering limitations. In conclusion, to systemize hospitals without patient-sitter, it is necessary to develop policies designed to establish criteria for the appropriate nurse to patient ratio and skill-mix, to standardize the work, to prepare finances for securing nursing staff, to evaluate the nursing demands, and to monitor the quality management.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• v.9 no.1
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• pp.1141-1144
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• 2005

In this paper, we propose an automatic displacement system for testing stability of structure. Photogrammetry is a method which can measure accurate 3D data from 2D images taken from different locations and which is suitable for analyzing and measuring the displacement of structure. This paper consists of camera calibration, feature extraction using coded target & retro-reflective circle, 3D reconstruction and analyzing accuracy. Multi-view camera which is used for measuring displacement of structure is placed with different location respectively. Camera calibration calculates trifocal tensor from corresponding points in images, from which Euclidean camera is calculated. Especially, in a step of feature extraction, we utilize sub-pixel method and pattern recognition in order to measure the accurate 3D locations. Scale bar is used as reference to measure. the accurate value of world coordinate..

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.17 no.1
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• pp.21-32
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• 1999

Mapping and precise point determination by photogrammetry have been shown to be an economic solution. But control points are necessary to determine the exterior orientation parameters. Although the number of required control points has been reduced based on extended bundle adjustment and reinforced cross-strip, the ground survey is a significant factor of whole expenses in photogrammetry. The status of GPS-photogrammetry with kinematic DGPS-positioning to overcome this disadvantages, is now steadly progressive since the first possibility has been proved. The completed satellite configuration, powerful receiver function and upgraded software for kinematic DGPS-positioning have extensively improved the accuracy of combined bundle adjustment. So the research for the operational use of GPS-photogrammetry is absolutely necessary. The presented test field was designed for identification of subsidences in a coal mining area, flown with 60％ sidelap and cross strips. Just with 6 control points and combined block adjustment instead of the traditionally used 21 horizontal and 81 vertical control points the same ground accuracy has been reached. The accuracy of kinematic GPS-positioning and combined block adjustment was independent upon the distance of the ground reference station. It also has been showed that the special model for the systematic error correction in the combined block adjustment.

• Journal of Institute of Control, Robotics and Systems
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• v.5 no.1
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• pp.16-24
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• 1999

본 논문은 불확정 시스템의 견실한 이상검출기법의 적용을 위한 실시간 이상검출기법에 대하여 다루며 대상 시스템은 산업용보일러 시스템이다. 본 논문에서 기술된 이상검출기법은 Kwon (1994) 등에 의하여 이미 제시된바 있는 견실한 이상검출기법의 오프라인 배치 처리 알고리즘을 실시간 적용을 위해 확장된 것이며 모델링 오차에 의한 불확실성, 비선형 시스템을 특정 동작점에서 선형화 하는 과정에서 발생하는 선형화 오차, 잡음 등을 고려하였고, 보일러 시스템을 대상으로 한 모의 실험을 통해 본 알고리즘의 우수성을 보였다.

• 한국신재생에너지학회:학술대회논문집
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• 2009.06a
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• pp.53-56
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• 2009

반사와 굴절이 합쳐진 새로운 형태의 하이브리드 태양광 집광 장치로 기존 집광 장치에 비해 초점 거리가 짧게 설계되었다. 프레넬 렌즈 형태의 굴절부와 프레넬형의 다수의 포물선 반사경이 공통으로 후면 초점(rear focus)을 가지도록 배치하여 기존 프레넬 렌즈만으로 구성된 것보다 선형 집광의 경우는 3배, 점 집광의 경우는 10배 이상 집광비를 높일 수 있다.아울려 이를 이용한 선형 집광형 발전 시스템과 점형 집광 장치는 나름대로 장점을 가진다.