• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2006.05a
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• pp.164-169
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• 2006

본 연구는 가정용 가스 보일러의 배기가스 유동특성을 전산유체역학을 이용하여 정밀 분석하고 CO 검지 장치의 최적화 설계를 결정하는 것을 목적으로, CFD 상용코드 FLUENT 6.2를 이용하였다. 배기가스 포집위치에서 가스 유속의 균일성과 CO농도 검출기에서의 속도가 주요 성능 인자이며 포집기의 위치, 포집구멍의 크기 및 배기가스의 유량을 주요 변수로 선택하였다. 포집기의 위치는 배기부의 상부와 하부인 두가지의 경우이고 두 경우의 배관 높이 차이는 10 mm이다. 포집구멍의 직경 변화는 3 mm, 4 mm 및 5 mm인 세가지 경우이다. 마지막 변수인 배기가스의 유입속도는 20,000 kcal/hr용량의 k사 가스 보일러가 공기비 1.1일 경우에 정상 연소시 0.5 m/s임을 알았고 저부하와 고부하일 경우를 고려해서 0.3 m/s, 0.5 m/s 및 0.7 m/s의 세가지 경우를 변수로 결정하여 총 18가지 형태의 대상을 전산유체 역학을 통해서 분석하였다. 궁극적인 목표였던 배기가스의 균일성은 한가지 경우를 제외 하고는 만족할만한 결과를 얻었기 때문에 CO검지 장치가 위치할 곳에서의 속도 및 포집구멍의 크기가 CO농도 검출기 유속의 주요 인자라 할 수 있다. 결론적으로 포집구멍의 크기가 5 mm인 6가지 경우 중에서 두가지 경우는 검지장치의 유효속도를 초과하였고 포집구멍의 크기가 3 mm인 경우는 검지장치의 유입 속도가 상대적으로 작으므로 포집구멍의 크기는 4 mm가 적합한 것으로 판단하였다.

• Journal of Korean Society of Forest Science
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• v.98 no.6
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• pp.799-805
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• 2009

To construct the production system of forest biomass as a small scale heating energy source, energy availability of wood-chip was examined by cost and energy balance analysis in the production process. The costs to produce wood-chip of 1 kg was calculated by yarding machines and their operational gradient conditions. As a result, 195.45~210.54 won/kg were required as production costs of wood-chip. Input energy rate (%) which is output to input energy in wood-chip production process were showed as 26.58~27.38%. Energy input rate by operational gradient was not significantly difference, and scenario B with tower yarder system appeared by more efficient than scenario A with tractor yarding system in opposition to production costs analysis.

• BMB Reports
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• v.50 no.3
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• pp.126-131
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• 2017

P48 Ebp1 is expressed in rapidly proliferating cells such as cancer cells and accelerates cell growth and survival. However, its expression pattern and role in central nervous system development have not been studied. Here, we demonstrated the spatiotemporal expression pattern of p48 Ebp1 during embryonic development and the postnatal period. During embryonic development, p48 Ebp1 was highly expressed in the brain. Expression gradually decreased after birth but was still more abundant than p42 expression after birth. Strikingly, we found that p48 Ebp1 was expressed in a cell type specific manner in neurons but not astrocytes. Moreover, p48 Ebp1 physically interacted with beta tubulin but not alpha tubulin. This fits with its accumulation in distal microtubule growth cone regions. Furthermore, in injured hippocampal slices, p48 Ebp1 introduction promoted axon regeneration. Thus, we speculate that p48 Ebp1 might contribute to microtubule dynamics acting as an MAP and promotes CNS axon regeneration.

• Composites Research
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• v.27 no.3
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• pp.90-95
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• 2014

Cure shrinkage during cure process of polymer matrix composites develope residual stress that cause some structural deformation, such as spring-in, spring-out and warpage. The carbon/epoxy prepreg used in this study is Hexply M21EV/34%/UD268NFS/IMA-12K supplied by Hexcel corp. Cure shrinkage and degree of cure measured by TMA(thermomechanical analyzer) and DSC(differential scanning calorimetry). Cure shrinkages are measured by TMA within a temperature range of $140{\sim}240^{\circ}C$ in a nitrogen atmosphere, and degree of cure determined by the heat of reaction using dynamic and isothermal DSC runs in argon atmosphere. As a result, the cure shrinkage is increased dramatically in a degree of cure range between 27~80%. the higher the cure temperature, the lower the degree of cure occurring to begin cure shrinkage.

• Journal of Korean Society for Geospatial Information Science
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• v.15 no.4
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• pp.31-39
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• 2007

As the availability of images from airborne digital camera with high resolution is expanded, a lot of concern are shown about the production of orthoimage and digital map. This study presents the method of updating digital map using orthoimage from airborne digital camera image. Images were georectified using GPS surveying data. For the generation of orthoimage, Lidar DEM was used. The absolute positional accuracy of orthoimage was evaluated using GPS surveying data. And that of the building layer of digital map was estimated using the existed digital map at the scale of 1:1,000. The absolute positional accuracy of orthoimage was as followed: RMSE in X and Y were ${\pm}0.076m$ and ${\pm}0.294m$. The RMSE of the building layer were ${\pm}0.250m$ and ${\pm}0.210m$ in X and Y directions, respectively. The RMSE of the digital map using orthoimage from Aerial Digital Camera image fell within allowable error range established by NGII. Consequently, updating digital map using orthoimage from Aerial Digital Camera image can be applied to various fields including the construction of the framework data and the GIS of local government.

• Journal of Information Management
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• v.37 no.3
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• pp.61-84
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• 2006

In this paper, we proposed one of the methods for building thesaurus in Science & Technology domain and investigated its applicability as an inference service based on ontology. There exist as many building methods for thesaurus as its role and function, and actually many thesauri capable of ensuring the accuracy and efficiency in information search are being built by many experts. After examining the previous studies related to the principles of building thesaurus and relevant concept "facet", we focused on its characteristics and applied it to building thesaurus. The facet is classified into 2 categories, conceptual facet and relational facet. The latter contains 3 subcategories: category relational facet, attribute relational facet and thematic relational facet. The thesaurus for Science & Technology domain using facets can be applied as a web-based inference service. As a result, the three types of inference service, COP(Communities of Practice), Researcher Tracing and Research Map are provided by means of ontology, and can be applied for the Query Expansion.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.24 no.6
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• pp.703-709
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• 2015

In this work, a robot aimed at grapping and delivering an object by using a simple finger-pointing command from a hand- or arm-handicapped person is introduced. In this robot system, a Leap Motion sensor is utilized to obtain the finger-motion data of the user. In addition, a Kinect sensor is also used to measure the 3D (Three Dimensional)-position information of the desired object. Once the object is pointed at through the finger pointing of the handicapped user, the exact 3D information of the object is determined using an image processing technique and a coordinate transformation between the Leap Motion and Kinect sensors. It was found that the information obtained is transmitted to the robot controller, and that the robot eventually grabs the target and delivers it to the handicapped person successfully.

• Korean Journal of Veterinary Service
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• v.26 no.2
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• pp.121-128
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• 2003

This study was carried out to identify and investigate antimicrobial susceptibility for Mannheimuia haemolytical which is responsible for shipping fever. Samples were collected from nasal and lung of 100 adult healthy cattle which are slaughtered in Samsung meat corporation located in Incheon metropolitan city. lung lesion index have been investigated within 0-5 range according to Shewen and Willkie(Can J Vet Res 52:30-36, 1988). Eighty-seven of 100 cattle were under normal condition with 0-1 ranges. A total of 129 strains were collected from blood and tryptic soy agar. Among these strains, 100 strains were identified with Staphylococcus, Streptococcus and enterobacteria containing E coli. Biochemical and fermentation assay of arabinose, trehalose, xylose, mannose, mannitol, lactose and salicin were tested to identify with Mannheimia sp. for 7 strains shown haemolytic activity on blood agar. Five strains were identified with Mannheimia haemolytica and 2 strains were untyped. In seasonal survey, Mannheimia sp recovered from fall to winter(5 of 7) have been highly isolated rather than those from spring to summer(2 of 7). Mannheimiz haemolytica were susceptible to antibacterials tested in this study but more resistant to oxytetracycline and streptomycin.

• Journal of Korean Society on Water Environment
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• v.22 no.5
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• pp.784-795
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• 2006

The purpose of this study was to assess biological river water quality by using epilithic diatoms at 40 selected sites in Geum, Youngsan, and Seomjin River systems. The sampling and analyses were performed during three seasons including January, April and June in 2005. Various water quality parameters also were analyzed. We attempted to classify the water quality condition by epilithic diatom indices (DAIpo and TDI) with the results of corresponding analyses of various chemical water quality parameters. A five class system was delivered to describe the water quality condition ranged from "very good" to "very poor." We also proposed a way of classifying water quality condition by combining two diatom indices of DAIpo and TDI. Our results showed that biomass of epilithic diatoms varied not only seasonally but spatially; it was not likely that winter diatoms represent average water quality condition, due to high concentration of nutrients. Water quality status assessed by diatom indices was generally worse than that assessed by BOD, indicating that BOD standard likely underestimates the biological condition of the water body. Importantly, nutrient-based diatom index (TDI) generally overestimated organic matter-based index (DAIpo) at most study sites, indicating that diatoms in studied rivers were likely more affected by nutrients than organic matter. Thus, management strategy to improve river water quality in Korea is suggested to emphasize more on the nutrients than organic matters.

• Journal of Korean Society on Water Environment
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• v.22 no.5
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• pp.768-783
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• 2006

Biological stream environment assessment has been an essential trend of aquatic ecosystems among advanced countries, because the chemical water quality assessment has limitations that only represent temporal water environmental status. Benthic macroinvertebrates are the most popular bioindicator group useful to biological water quality assessment for a long time. In addition, a number of indices using benthic macroinvertebrates have recently been developed not only for water quality assessment but also for ecological health assessment. In this paper Korean Saprobic Index (KSI) based on Zelinka-Marvan's saprobic valency concept is developed by applying DIN 38410 in Germany. The KSI value was widely applicable to most Korean streams with the exception of sand-based large streams, for example main stream of Nakdong River. But as a result of non-linear regression analysis the correlation between KSI and $BOD_5$ concentration was high and KSI reflected water quality alteration for mid and long-term period. In spite of applicability of KSI, it should be supplemented and developed to make it strong by accumulating field data as well as to manage integrated water environment in general through continuous biomonitoring.