• Journal of the Korean earth science society
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• v.32 no.7
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• pp.881-901
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• 2011

The science museum in the past satisfied visitors only by interacting them with simple objects and exhibition, while one in modern times was requested to meet the need of visitors in their engagement in educational programs. To meet the visitors' need, the science museum made efforts to train, educate, and assign docents so that they can interact with visitors and serve the educational purpose of visitation. In this study, we analyzed the strengths and weakness of docent training programs from science museums/science centers nationally and internationally, to make implication on how to design a docent training and professional program. Programs from four national and four international science centers/museums were selected as a sample for analysis. Their docent training programs were compared with the data of surveys and interviews and emails from docents and docent managers/evaluators. Artifacts and documents of the docent training programs were also collected and used to construct the validity in analyzing the data, resulting in the well-developed docent training program as the critical one for enriching science museum education. The results included; First, we need to recruit and train docents who interact visitors directly but they need to be differentiated from regular volunteers for promoting science museum education for the purpose of popularization of science. Additionally, Second, we need to develop and run docent training program where docents can experience 'informal learning' exhibition interpreting strategies through the real field from mentoring from the experienced/senior docents beyond 'formal learning' exhibition content. Third, we need to equip docents with skills to make scientific literacy possible at science museum-such as experiencing scientific ethics through scientific inquiry-which happens limited at school education.

• Applied Microscopy
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• v.31 no.3
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• pp.287-305
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• 2001

To investigate a role of cartilage canals in osteogenesis and growth of the vertebrae, in human fetuses ranging from 50 mm to 260 mm crown rump length were studied by electron microscopy. The initial appearance of cartilage canals of the vertebral body was observed at 60 mm fetus. In 80 mm fetus, primary ossification center in the vertebral body was first noted. The vertebral body showed calcified chondrocytes surrounded by a tone of hypertrophied chondrocytes and deep canals which terminated in calcified matrix. Most hypertrophied chondrocytes in the centrum showed in various stage of degeneration in disorderly arrangement. At the blind end of deep canal, osteogenic cells, osteoblasts and chondroclasts were observed. Resorption of unmineralized cartilage septa was undertaken by perivascular cells within cartilage canals. The ruffled border of the chondroclast was restricted to resorption site of calcified cartilagenous matrix. The periosteal bone formation was followed by the appearance of primary center of the centrum at 120 mm fetus. The osteoblasts of the perichondrium started to lay down a thin membranous bony lamella on the outer surface of the osseous trabeculae of the centrum. The processes of bone formation in the vertebral bodies were found to possess morphological similarities to that occurring at secondary center of the epiphysis of a long bone. These results indicate that the connective tissue cells within the cartilage canals proliferate and differentiate into osteoblasts at the site of endochondral ossification of the vertebrae.

• Applied Microscopy
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• v.42 no.2
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• pp.67-76
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• 2012

The biomimetic approach on the cuticular spinning nozzles of the major ampullate silk glands in the golden-web spider Nephila calvata has been attempted using various visualizing techniques of light and electron microscopes to improve the design of spinning nozzle for producing synthetic nanofibers spun from electrospinning apparatus. The major ampullate spigot which has the most effective nozzle system to produce nanofibers for dragline silk with high strength and elasticity is connected via the bullet type spigot on anterior spinneret with flexible terminal segment. The excretory duct which transports the liquid silk feedstock from ampulla to spigot is divided into 3 limbs by loops back on itself to form an S-shape morphology that is bundled in connective tissue. Final diameter of the nanofibers at nozzle was dramatically reduced by gradual narrowing of duct cuticle less than 10 times comparing to its original size of funnel region. Moreover, the funnel has a characteristic cuticular organization with porous microstructure which seems to be related to water removal from feedstock of silk precursors. High magnification electron micrographs also reveal the presence of the spiral grooves on the surface of the cuticular intima near the valve which presumed to reduce friction during rapid flow of liquid silk.

• Journal of Digital Convergence
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• v.15 no.1
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• pp.267-275
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• 2017

The purpose of this study was to evaluate the clinical availability of ankle-brachial index(ABI) according to severity of cardiovascular disease. The subjects of this study were the patients who had ABI in a general hospital. In this study, total 441 patients were enrolled for analysis. Electric medical records were reviewed to investigate the result of ABI and severity of cardiovascular disease measured vessel disease and Gensini score. Collected data were analyzed using SPSS 21.0 program. Subjects with $ABI{\leq}0.90$ and > 0.90 were classified as having abnormal and normal ABI. There were significant differences in vessel disease categorization($x^2=4.731$, p=.030) and Gensini score(t=2.351, p=.019) between two groups. Therefore, ABI is an effective and non-invasive tool for the diagnosis of cardiovascular disease with high severity. ABI is a valuable predictive index of ischemic heart disease.

• Journal of Korean Society of Archives and Records Management
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• v.14 no.3
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• pp.33-54
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• 2014

This study aims to expose the current status of the transfer of public digital records. Based on the PAIMAS transfer methodology, it identified the domains of transfer in the Korean public sector. Through the result of the interviews with experts in the field, this study examined what the records centers and the National Archive of Korea had prepared using the domains. Through the examination, the expected problems and subject to be discussed were thus presented, which are expected to provide a forum for further discussions.

• The Journal of the Korea institute of electronic communication sciences
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• v.6 no.5
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• pp.717-722
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• 2011

This paper presents that the electronic controller is developed for controlling the setting temperature and water in the ceramic pipe system. The heating water system is designed for controlling the temperature to supply the heat through the ceramic pipe heater to input the water, also for controlling quantity of water using the water sensor and impeller. The control method of the heating water system is applied the mathematic modeling of the ceramic pipe heater on the suppling the heat at coming water, and the test result of the electronic controller is present to smartly control the setting temperature, therefore the ceramic pipe heater is proposed to be able to apply the heating structure and the control methods as a product.

• Proceedings of the Korean Society of Computer Information Conference
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• 2021.07a
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• pp.475-476
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• 2021

일반적으로 대학생들은 연간 약 50만원이 소요되는 전공 서적 구매비용에 부담감이 있는 것으로 조사된다. 이러한 대학생들을 위해 비교적 저렴한 교재용 전자책 서비스를 전문적으로 제공해 주는 애플리케이션이 없다. 본 논문에서는 대학생들을 위한 전공 및 교양 교재를 대상으로 대여를 포함한 전자책 제공 서비스가 가능한 모바일 앱을 설계한다. 제시하는 서비스 앱은 교재용 전자책을 대상으로 온라인 서점, 출판사, 도선관 등으로부터 전자책 정보를 수집하여 사용자에게 제공하고, 이를 대상으로 대여 또는 구매가 가능한 서비스를 제공한다. 제공되는 전자책 파일은 불법 배포를 방지하기 위해 DRM 방식을 사용하여 전용 뷰어를 통해 제공되어지도록 설계한다. 개발되는 앱을 통해서 대학생이 겪는 문제 중 하나인 교재비용 경감과 더불어, 종이책 생산을 줄임으로써 지구환경 보존에 기여할 수 있다.

• Proceedings of the KIEE Conference
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• 2006.10b
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• pp.221-223
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• 2006

최근 수요가 급증한 36W 단일 캡 형광램프의 과열로 인하여 화재의 위험성이 대두되고 있다. 단일 캡 형광램프는 이중 캡에 형광램프에 비하여 길이가 작아 다루기가 쉽고, 관 지름이 작아 고효율의 형광램프로 인식되고 있다. 그러나 한쪽방향에 전극을 가지고 있어 열 분산 면에서 이중 캡에 비하여 열 축적 가능성이 크고, 수명말기에 전극필라멘트가 열에 의해 소실되었을 경우 관경이 작아 필라멘트 지지 스템(stem)의 길이가 가까워 고속스위칭의 전자식안정기를 적용한 시스템에서 완전히 개방되지 않고 임피던스의 상승만을 가져올 수 있다. 이로 인하여 캡의 열화에 의한 분리가 일어나고, 화재의 원인이 될 수 있다. 이러한 현상은 형광등의 수명 말기에 발생하는데 본 논문에서는 형광등의 수명말기 현상을 모델링하여 단일 캡 36W 형광램프의 수명 말기에 발생하는 과열에 관한 시험방법에 대하여 시험 연구 하였다.

• Journal of Korean Society of Forest Science
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• v.66 no.1
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• pp.64-67
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• 1984

The genus Salix is nowadays becoming increasingly important for both biomass energy production and the expanding paper industry. The enlarging plantations will however create some potential as well as problem. The great potential of genetical improvement as well as the prevention of pollen allergies requires knowledge about e.g, the pollen morphology of the most used Salix species. This study investigated the pollen morphology of Salix viminalis L. both on light microscope (LM) and scanning electron microscope (SEM).

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1993.10a
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• pp.136-141
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• 1993

진공챔버,위생튜브등 정밀한 내면을 필요로 하는 경우 표면거칠기를 향상시키기 위한 방법으로 전해가공 및 수작업을 하는 경우가 대부분인데 이는 가공비가 비씨고 다듬질 시간이 많이 걸리는 등 매우 비경제적이다. 더구나 길이가 긴 관이나 구부러진 관의 내면은 기계적으로 다듬질이 매우 어렵다. 그러나 최근에 개발된 전자기장을 이용한 자력 연마가공법은 기존의 기계적인 가공법과는 달리 실제 가공을 행하는 공구부와 ㅣㅇ를 구동하는 구동부 사이에 공극을 허용하기 때문에 이를 이용하여 회전이 불가능한 곡관의 내면다듬질을 가능하게 하였다. 지금까지 연구들은 단순히 전자석 및 전원으로 이루어진 수동가공 시스템으로서 가공공정 자체의 특성파악에 집중되어 왔으나 자력연마법의 장점중의 하나인 다듬질 공정의 자동화 가능성을 실현시키기 위해서는 공정의 제어가 필요하다. 본 연구에서는 이를 실현시키기 위한 기초연구로서 컴퓨터구동 회전자력연마가공 시스템을 개발하고 그 기본특성을 알아보기 위해 유한요소법을 이용하여 원형 요오크 및 여섯개의 자극에 대해 자력선의 분포를 알아보았다. 또한 이로부터 가공영역의 자속밀도를 계산하고 다듬질 가공을 가능케 하기위한 회전자화의 발생방법에 대해 고찰하였다.