• Journal of Astronomy and Space Sciences
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• 제31권4호
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• pp.317-323
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• 2014

Odyssey, one of the NASA's Mars exploration program and SELENE (Kaguya), a Japanese lunar orbiting spacecraft have a payload of Gamma-Ray Spectrometer (GRS) for analyzing radioactive chemical elements of the atmosphere and the surface. In these days, gamma-ray spectroscopy with a High-Purity Germanium (HPGe) detector has been widely used for the activity measurements of natural radionuclides contained in the soil of the Earth. The energy spectra obtained by the HPGe detectors have been generally analyzed by means of the Window Analysis (WA) method. In this method, activity concentrations are determined by using the net counts of energy window around individual peaks. Meanwhile, an alternative method, the so-called Full Spectrum Analysis (FSA) method uses count numbers not only from full-absorption peaks but from the contributions of Compton scattering due to gamma-rays. Consequently, while it takes a substantial time to obtain a statistically significant result in the WA method, the FSA method requires a much shorter time to reach the same level of the statistical significance. This study shows the validation results of FSA method. We have compared the concentration of radioactivity of $^{40}K$, $^{232}Th$ and $^{238}U$ in the soil measured by the WA method and the FSA method, respectively. The gamma-ray spectrum of reference materials (RGU and RGTh, KCl) and soil samples were measured by the 120% HPGe detector with cosmic muon veto detector. According to the comparison result of activity concentrations between the FSA and the WA, we could conclude that FSA method is validated against the WA method. This study implies that the FSA method can be used in a harsh measurement environment, such as the gamma-ray measurement in the Moon, in which the level of statistical significance is usually required in a much shorter data acquisition time than the WA method.

• 농촌계획
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• 제21권4호
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• pp.1-12
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• 2015

Various types of parks such as ecological park, dragonfly park, etc. are tried to design in order to resolve different environmental issues in urban areas. Parks are considered organism habitats that not only improve the biodiversity but also give people a chance to observe living organisms in urban area. This study was conducted to select basic materials for planning a butterfly garden through reference reviews. The following 21 species of butterflies belonged to 1 order, 4 families, and 16 genera were selected: Phengaris teleius, Pseudozizeeria maha, Thecla betulae, Argynnis hyperbius, Dichorragia nesimachus, Hestina assimilis, Polygonia caureum, Sasakia charonda, Vanessa cardui, Vanessa indica, Boloria selene, Byasa alcinous, Papilio machaon, Papilio macilentus, Papilio protenor, Papilio xuthus, Papilio bianor, Sericinus montela, Colias erate, Eurema hecabe, and Pieris rapae. 85 species belonged to 22 families, 59 genera, 74 species, 10 varieties, and 1 subspecies were selected for host and nectar plants for butterflies selected above. These results would be expected to useful in butterfly gardening. After that, we think it is necessary to be applied these study results in field. This study requires a test in the butterfly garden. The test results will be make the butterfly-plant matrix.

• 대한치과교정학회지
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• 제52권1호
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• pp.29-41
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• 2022

Objective: Condylar resorption (CR) is one of the major post-surgical complications of orthognathic surgery. This systematic review (SR) aimed to evaluate epidemiological data, risk factors, and therapeutical management of CR. Methods: Six databases were screened by two investigators until September 2020 to obtain all SRs. After reading the titles and abstracts, eligible SRs were determined and data extraction was performed. Using the latest version of A Measurement Tool to Assess Systematic Reviews, the methodological quality of the included SRs was determined. Results: Ten SRs with low or critically-low methodological quality were included in this review. Mandibular hypoplasia on the sagittal plane and hyperdivergent growth pattern on the vertical plane were the most common skeletal alterations in which CR could occur after orthognathic surgery. Post-operative condylar changes were analyzed both on two-dimensional and three-dimensional (3D) radiographic examinations. The incidence of CR was not related to the fixation method. Based on the severity of the pathological conditions, management of CR can include conservative or surgical therapy. Conclusions: Despite the limited evidence in literature, CR is considered a consequence of orthognathic surgery. However, an accurate diagnosis of CR and a better orthognathic surgical planning must include 3D radiographic examinations to improve pre- and post-surgical comparison. Well-designed studies with long-term follow-up and 3D data are needed to clarify the findings of this analysis..

• 항공우주산업기술동향
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• 제6권1호
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• pp.3-13
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• 2008

우주분야에서의 2007년은 역사적으로 기념할 만한 해였다. 구소련의 스푸트니크가 1957년 10월 4일 발사되어 50주년을 맞이하였고, UN이 우주의 평화적 이용을 선언한지 40주년이 되는 해이기도 하다. 그리고 2007년과 2008년 초에는 일본과 중국의 달 탐사위성 발사 성공, 유럽과 일본의 국제우주정거장 실험모듈 조립성공, 중국의 위성요격시험 시도, 그리고 한국 최초의 우주인 배출사업 성공 등 다양한 변화들이 돋보인 한 해였다. 2007년 주요국 정부의 우주개발 예산은 총 783억불로 전년 대비 36% 증가하였으며, 탐사분야에서는 세계 탐사 전략과 협력 프레임워크가 발표되면서 달탐사에 대한 전 세계 14개국의 국제협력 방향이 마련되었다. 우주산업 매출은 2006년 1,061억불 규모로 전년 대비 20% 증가하였으며, 2007년 매출은 1,739억불로 예상되고 있다. 본 논문에서는 특히 지구관측위성 연구개발과 제도, 이로 인해 파생되는 영상데이터 및 서비스 시장의 동향과 전망을 자세히 분석하였다. 우리나라의 2008년 우주개발 예산은 3,164억원이며, 2007년 우주산업 생산규모는 1억불이다. 다목적실용위성 3, 3A, 5호, 통신해양기상위성의 개발과 소형위성발사체 개발 등의 연구사업이 진행 중이며, 올 해 완공되는 나로 우주센터에서 과학기술위성2호가 탑재된 소형위성발사체를 연내 발사할 예정이다.