• Applied Microscopy
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• v.35 no.4
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• pp.91-97
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• 2005

The acinar cells and secretory granules of the parotid salivary gland were examined in the lesser white toothed shrew, Crocidura suaveolens and the big white-toothed shrew, C. lasiura. The parotid gland of both species were a serous gland having only one kind of serous acinar cells, and had conventional arrangement of acini and intercalated, granular and striated ducts. In case of C. suaveolens, serous acinar cells had well developed rER, prominent Golgi complex, several large mitochondria and abundant moderate dense secretory granules with various stages of the maturing or fusing process. Immature acinar secretory granules were only or mainly filled with fine strong dense specks and had an indistinct limiting membrane, and mature granules were filled with homogeneous pale large round center and had fine strong dense specks at the periphery of the homogeneous pale center and a distinct limiting membrane. In case of C. lasiula, serous acinar cells had well developed rER, prominent Golgi complex, several large mitochondria and abundant dense secretory granules with maturing or fusing process. Immature acinar secretory granules were only filled with pale rough specks and had an indistinct limiting membrane, and mature granules were only filled with rough dense specks and had a distinct limiting membrane. Eventually The acinar secretory granules of C. suaveolens were seen moderate at the light and ultrastuctural level, those of C. lasiura were strong dense at the light microscopic level and dense at the ultrastructural level.

• The Journal of the Korea institute of electronic communication sciences
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• v.9 no.3
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• pp.311-322
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• 2014

This study was conducted to assess the impact of work-related musculoskeletal disorders (WMSDs) on health related quality of life (QoL) in the firefighter under the recent IT environment. The data were collected by face to face interview using a structured questionnaire in the 366 respondents. WMSDs symptoms were measured by a self-assessed questionnaire on symptom table of NIOSH and health-related QoL was measured by SF-36. The prevalence of WMSDs was 38.0% in upper limbs, 35.5% in the low back, 21.6% in lower limbs, and 59.3% in two or more parts of the body. Subjects with symptoms of WMSDs had significantly lower scores in 7 dimensions of QoL except 'emotional role limitation' than those without symptoms of WMSDs at the area of upper extremities (neck, shoulder, arm/wrist, and hand/wrist/fingers). On the other hand, subjects with symptoms of WMSDs had significantly lower scores on all QoL dimensions than those without symptoms of WMSDs at the area of lower back or lower extremities. These results suggest that WMSDs had a negative effect on QoL. Therefore, prevention of WMSDs should be considered intervention strategies for improvement of QoL, especially in firefighters.

• Journal of the Korean Society for information Management
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• v.26 no.1
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• pp.371-387
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• 2009

National Institute of Korean History(NIKH) is the major collecting organization of manuscripts, records for historical research and develops a Collecting Manuscripts Management System. Manuscripts description conforms to records management system, such as provenance information and hierarchical catalog records and business process observes library management system because it is not the public records. Goal system is integrated system containing both. This study proposes development of Collecting Historical Manuscripts Management System in the NIKH and the aspects to achieve successful system operation.

• Journal of Advanced Marine Engineering and Technology
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• v.37 no.8
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• pp.849-854
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• 2013

Many researches on green ship with increasing on economics, efficiency and convenience have been carried out consistently. One of them is development of diesel engines with electronic control. While small duty one for automobiles had been adopted mainly already, disseminating heavy duty one for ships has trouble due to safety and reliability. In order to solve these problem in this study, performance of electronic control and cam type engine installed in parallel on training ship HANBADA of korea maritime university was analyzed and compared. It is certain that specific fuel oil consumption of the electronic control type is lower than cam type and excellent at lower engine load, especially. And the electronic control type shows more effective characteristic at sea trial on specific fuel oil consumption.

• Journal of the Korean Geophysical Society
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• v.6 no.4
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• pp.261-268
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• 2003

Lots of various utilities are buried under the surface. The effective management of underground utilities is becoming the very important subject for the harmonious administration of the city. Ground Penetrating Radar(GPR) survey including other various underground survey methods, is mainly used to detect the position and depth of buried underground utilities. However, GPR is not applicable, under the circumstances of shallow depth and places, where subsurface materials are inhomogeneous and are composed of clay, salt and gravels. The aim of this study is to overcome these limitations of GPR and other underground surveys. High-frequency electromagnetic (HFEM) method is developed for the non-destructive precise deep surveying of underground utilities. The method is applied in the site where current underground surveys are useless to detect the underground big pipes, because of poor geotechnical environment. As a result, HFEM survey was very successful in detecting the buried shallow and deep underground pipes and in obtaining the geotechnical information, although other underground surveys including GPR were not applicable. Therefore this method is a promising new technique in the lots of fields, such as underground surveying and archaeology.

• The Magazine for Energy Service Companies
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• s.67
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• pp.24-27
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• 2010

'2010 대한민국 녹색에너지대전'이 지식경제부 주최, 에너지관리공단 주관으로 지난 10월 13일부터 16일까지 4일간 서울 삼성동 코엑스홀에서 개최되었다. 올해로 30번째를 맞이한 대한민국 녹색에너지대전은 그 어느 해보다 의미가 크다고 할 수 있다. 30년이라는 긴 역사에 걸맞게 LG전자 현대중공업 삼성중공업 OCI 효성 등 대한민국을 대표하는 에너지 관련 기업들이 대거 참여하였고, 정부가 2010년까지 온실가스 배출전망량(BAU) 대비 30% 감축하겠다는 목표를 제시함은 물론 그에 맞춰 에너지온실가스 목표관리제가 도입돼 에너지 절약에 대한 관심이 그 어느 때보다 높기 때문이다. 더욱이 올해 처음 개최되는 신재생에너지대전이 함께 열리면서 참가기업이 251개, 총 1,008개 부스로 확대되었고, 에너지 효율 향상에 관한 대표적 프로젝트로 성장하고 있는 ESCO 산업 특별 테마관이 마련되기도 하였다. ESCO 산업 특별 테마관은 국내 ESCO 업체인 삼성에버랜드 LIG엔설팅 금호이엔지 에너지솔루션즈 지멘스 테크윈 등이 직접 참여하여 최신 기술과 정보를 전달하고 관련 상담을 진행하였다. 또한 최근 각광을 받고 있는 LED 고효율 조명관을 특별 조성해 국가 경제의 차세대 성장동력인 친환경 조명기술을 선보이기도 했다.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2018.06a
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• pp.98.1-98.1
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• 2018

소듐냉각 고속로 (SFR)는 원자력 발전의 가장 시급한 문제점으로 부각되고 있는 사용 후 핵연료를 재활용 하여 가동하는 원자로 이다. Generation IV로 명명되는 차세대 원자로 중에 하나로 국제 공동연구와 자체 연구를 통해 우리나라 고유의 기술이 축적되고 개발되고 있다. 현재 소듐냉각 고속로의 가장 큰 문제점 중의 하나는 금속핵연료와 피복관의 상호반응이다. 상호반응이 일어나면 공융현상을 일으켜 피복관의 녹는점이 낮아지고 피복관의 두께가 얇아져 원자로의 안전에 치명적인 위협이 된다. 이러한 문제를 해결하기 위해 전해도금 (electro-plating)을 활용하여 HT9 피복관 내면에 크롬을 도금하여 금속핵연료와 피복관의 상호반응을 억제하는 연구가 본 연구팀에서 진행되고 있다. 크롬과 전해도금을 코팅 물질과 코팅 방법으로 선정한 이유는 튜브 내면에 적용하기 용이하고 경제적인 코팅 방법이기 때문이다. 본 연구에서는 여러 가지 전해도금 인자 중 온도와 pulse 전류의 파형이 상호반응 방지 효과에 미치는 영향에 대하여 고찰하였다. 도금액의 온도를 $50{\sim}80^{\circ}C$, 전류 파형 중 on/off time을 1:1, 10:1, 1:10으로 하여 여러 HT9 시편을 도금하였고 모의 금속 핵연료 합금인 Ce-Nd와 확산 반응 실험을 수행하여 상호반응 방지 효과를 분석하였다. 광학현미경과 전자현미경을 이용한 미세구조 분석 결과 도금액의 온도가 $65^{\circ}C$ 이하인 시편에서는 미세균열이 심하게 발생하였고 그 균열을 통해서 물질이 확산하고 상호반응을 한다는 것이 관찰되었다. $65^{\circ}C$보다 높은 도금액의 온도에서 형성된 크롬막은 균열이 없고 상호반응 방지 효과가 좋은 것이 확인되었다. 특히 전류 파형의 on/off time이 1:1일 때 상호반응 방지 효과가 가장 좋은 것을 확인하였다. 이러한 결과는 크롬 전해도금의 코팅 조건이 상호반응 방지 효과에 매우 중요한 요인으로 작용한다는 것을 말해주고 있다.

• Journal of Korean Society of Archives and Records Management
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• v.6 no.1
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• pp.113-136
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• 2006

This study aims for the above mentioned. After all, through the analysis of Electronic Question/Answering Function to understand a user's demand under online circumstances, groping for the method to provide an appropriate Archival Information Service is the most important thing. For this, in this study, it researched the users interviews and the research related to users as a precedence study, and the studies having examined the state of demanding information by users through analyzing the e-mail actually. Additionally, by looking over the study of Library and Information Science that is activated in a field of Electronic Question/Answering Function rather than Archival Science, as a matter of fact, the study has come up with the standard for analyzing Electronic Question/Answering Function. And based on the precedence study, the instances for the National Archives from USA, England, Australia and Canada were analyzed, and the chance of activating Archival Information Service were tried to grope for in the study. This study might be one of methodologies in examining the users study that is not activated yet in Archival Science. Therefore, the users study can be carried out in various methods as well as Electronic Archives/Answering Service. This study might be the important information in providing far better Archival Information Services. It is desirable that based on this opportunity, the study related to the various users by examining not only Electronic Archives/Answering Function but also Question/Answering of the users and the Archivists in the filed to the larger extend will be activated for Archival Science.

• Journal of the Korean Magnetics Society
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• v.25 no.2
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• pp.52-57
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• 2015

The focal spot of electron beam depending on the anode angle in the structure and major parts of the X-ray tube was investigated by the OPERA-3D/SCALAR simulation program. The simulation worked on four spaces with with two spaces, including anode and cathode of X-ray tube, by applying the finite element method analysis. The analytical model and dimension for the emission orbit of thermal electrons made from one filament of the focused X-ray cathode is affected to the penumbra of detector for the X-ray depending on any real focal spot size. The model shape of focusing cap and focusing tube with an anode target angle and a cathode filament is analyzed by the current density distribution of thermal electrons. The focusing width of thermal electrons for the X-ray tube depended on the anode angle (${\theta}$). The focusing value of electron beams at a region of anode angle having $10^{\circ}{\sim}17^{\circ}$ maintained to below value of $70{\mu}m$. The minimum focal size of the electron beam was $40{\mu}m$ at an anode angle of $15^{\circ}$. The focused X-ray tube of many variables depended on the thermionic emission of hot electrons from the target trajectory. The focusing tube will contribute to the real design of X-ray for the development of future diagnosis medical device.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.08a
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• pp.349-349
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• 2011

탄소나노튜브의 전자방출 특성을 활용하면 저전압으로 냉전자를 빠른 스위칭 속도로 전자를 용이하게 제어가 가능하다. 이로 인한 고성능 엑스선 소스를 이용하여 의료영상진단과 보안검색 분야에서 많이 사용될 것으로 예상이 된다. 본 연구에서는 고성능 탄소나노튜브 기반 엑스선의 미소초점 형성을 위한 전자 방출 시뮬레이션을 실시하였다. 3극관(애노드, 게이트, 캐소드)에서 2개의 포커싱 전극을 추가한 5극선관의 전자방출 궤적에 대한 시뮬레이션을 진행하였다. 3극관을 구성하여 애노드와 게이트에 일정 전압을 정해준 후, 2개의 포커싱 전극의 전압, 포커싱 전극간의 거리, 그리고 포커싱 전극의 내부직경을 조절함으로써 애노드 상에서의 전자의 초점이 작아지는 것을 알 수 있었다. 마이크로 포커스 엑스레이 소스는 의료영상진단에 있어서 고해상도 의료기기로의 응용이 가능하다.