• 농촌계획
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• 제24권2호
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• pp.91-100
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• 2018

This study aims to identify more reasonable and efficient development plans to engage local university students in landscape improvement projects in rural areas. To survey university students, residents, administrators and experts involved in such projects on important considerations in this regard, SWOT analysis was employed to identify important factors, followed by analytic hierarchy process (AHP) to evaluate their relative importance, identify problems and suggest implications for improvement. The results are summarized as follows: the relative importance of the SWOT group was in the order of opportunity, strength, threat, and weakness. For each SWOT factor, the relative importance of strengths was in the order of students' aspiration and passion, availability of creative ideas and designs, and improved attachment to their community. The relative importance of weaknesses was in the order of the lack of spontaneous participation of residents, short preparation periods and insufficient budgets, and the lack of experience in similar projects. The relative importance of opportunities was in the order of young students' activity itself being a boost factor to the community, students' endeavors arising a consensus among residents, and students feeling a sense of duty as representatives of their school. The relative importance of threats was in the order of projects being one-shot, temporary events, immaturity, and differences in preferences between older and younger generations. To draw an overall ranking of the sub-factors evaluated, the overall relative importance of the decision-making factors was evaluated. Among the sub-factors for each SWOT group, young students' activity itself being a boost factor to the community as an opportunity factor was shown to be the most important, while the lack of experience in similar projects was shown to be the least important as administrators and experts made appropriate interventions in each stage.

• 한국자동차공학회논문집
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• 제23권4호
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• pp.388-395
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• 2015

The waste gate valve (WGV) for gasoline vehicles operate in a harsh high-temperature environment. Hence, WGVs are typically made of Inconel 713C, which is a type of Ni-based superalloy. Recently, the metal injection molding (MIM) process has attracted considerable attention for parts used under high-temperature conditions. In this study, an MIM analysis for the head and other parts of the WGV is conducted using a commercial CAE program Moldflow. Further, optimal manufacturing conditions are determined by analyzing flow characteristics at various injection times and locations. Moreover, to improve the accuracy of the analysis results, we compare the actual temperature of the mold during injection processing with that observed through the analysis. As the results, metal injection patterns of analysis are well in accord with these of short shot test. And the temperature variations of analysis is also very similar with those of feedstock when metal injection molding.

• 한국콘텐츠학회논문지
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• 제12권9호
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• pp.68-79
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• 2012

영화는 내러티브의 구현을 위해 다양한 기법들이 서로 유기적으로 상호작용하여 관객의 지각에 영향을 준다. 영화 형식을 구성하는 기법들은 형식적 체계로서 영화의 내용과 동기화되어 특정한 효과를 유발시켜 관객의 정서적 체험의 강도와 깊이를 강화시켜주는 역할을 한다. 본 연구는 시각적 내러티브의 하나인 구도미학에 관한 연구로 충격적인 실화를 재구성한 영화 <도가니 SILENCE>(2011)를 분석 대상으로 삼았다. 본 연구는 치밀한 화면구성과 기법의 활용이 극대화된 영화 <도가니>의 내러티브에 적용된 구도기법을 분석해보고, 나아가 영화형식의 의미와 중요성을 제고해 보는 것이 연구목적이다. 이러한 연구는 영화에 내재되어 있는 의미와 정서가 쇼트를 통해 어떻게 시각적으로 구현되는지, 나아가 구도가 서사화법으로서 어떻게 영화재 기능을 수행하는지 고찰해 보는 것에 그 의의가 있다고 할 수 있다.

• 한국전자통신학회논문지
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• 제13권1호
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• pp.107-112
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• 2018

근래에는 드론을 이용하여 실생활에 적용하는 사례가 늘고 있다. 드론을 이용하여 방송국에서 항공촬영을 하거나, 드론 경기등 다양한 영역에 적용하고 있다. 특히 몇 년 전부터는 드론을 활용하여 고속도로 상에서의 교통위반 차량을 단속하고 있다. 경찰당국에서는 30분 단위로 단속을 하는 '스팟 이동식' 방식을 사용하고 있으나, 적은 인력으로 넓은 지역을 단속하기에는 비효율적인 방식이다. 따라서, 다수의 드론을 무선망으로 연결하여 체계적으로 관리할 수 있는 시스템이 필요하다. 본 논문에서는 고속도로에 적합한 MANET 드론 통신망에서 다양한 라우팅 프로토콜을 적용하여 가장 효율적인 라우팅 프로토콜을 선택하고자 한다. 이를 위해 OPNET 시뮬레이터로 라우팅 프로토콜을 적용한 드론 패트롤망을 디자인하고 시뮬레이션을 하였다.

• 한국주조공학회지
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• 제31권5호
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• pp.274-283
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• 2011

The vacuum die casting is a promising candidate of the stamping process for fabrication of fuel cell bipolar plate due to its advantages, such as precision casting, mass production and short production time. This study proposes vacuum die casting process to fabricate bipolar plates in fuel cell. Bipolar plates were fabricated under various injection conditions such as molten metal temperature and injection velocity. Also, according to injection velocity conditions, simulation results of MAGMA soft were compared to the experimental results. In case of melt temperature $650^{\circ}C$, misrun occurred. When the melt temperature was $730^{\circ}C$, mechanical properties were low due to dendrite microstructure. Injection velocity has to set at more than 2.0 m/s to fabricate the sound sample. When melt temperature, injection velocity (Fast shot), and vacuum pressure are $700^{\circ}C$, 2.5 m/s and 30 kPa respectively, sample had good formability and few casting defects. Simulation results are mostly in agreement with experimental results.

• 대한전자공학회논문지SP
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• 제45권5호
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• pp.95-102
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• 2008

이 논문은 고강도매질 CR(Computed Radiography) 영상의 잡음을 모델링하는 적절한 접근법을 제시한다. 잡음 유형의 통계적이고 비선형적 특성이 구체적으로 고안되었다. CR영상은 컴퓨터 처리에 의해 코드화되기 이전 이미 훼손된다. 다양한 형태의 잡음은 비록 디지털화된 상태로 검출된다 하더라도 통상 방사선 영상을 오염시킨다. 양자 방출시의 포아송 분포는 CR 영상판에서의 광자 분포에서 포아송 잡음 분포를 항상 유지하지 않는다. 그 통계적 특성은 재질 특성에 의해 상대적이며 경우의존적이다. 통계적 잡음모델링 과정에서 통상적인 포아송, 이항 내지는 가우스 통계분포의 가정이 고려되었으며 아울러 비선형 효과 또한 포함시켰다. 이는 잡음 영역의 고저 전 방사선량에 걸쳐 추정하는 해석적 모델을 구현한다. 그리고 이 분석적 접근은 고강도 강판튜브 스텝웨지의 방사선측정실험을 통해 관측한 CR 영상데이터에서 구현되었다. 그 결과는 매질의 두께변화에 따른 잡음의 일관성, 잡음분포특성, SNR 및 비선형 보간을 측정하는 상호비교의 파라미터연구에 유용하다.

• Journal of Ecology and Environment
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• 제43권4호
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• pp.400-420
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• 2019

The aims of the study were to analyze (1) the effects of Prosopis juliflora (Prosopis) on the spatial distribution and soil seed banks (SSB) diversity and density, (2) the effects of environmental factors on SSB diversity and density (number of seeds in the soil per unit area), and (3) the effects of animal fecal droppings on SSB diversity, density, and dispersal. Aboveground vegetation data were collected from different Prosopis-infested habitats from quadrats (20 × 20 m) in Prosopis thickets, Prosopis + native species stand, non-invaded woodlands, and open grazing lands. In each Prosopis-infested habitats, soil samples were collected from the litter layer and three successive soil layer, i.e., 0-3 cm, 3-6 cm, and 6-9 cm. Seeds from soil samples and animal fecal matter were separated in the green house using the seedling emergence technique. Invasion of Prosopis had significant effects on the soil seed bank diversity. Results revealed that the mean value of the Shannon diversity of non-invaded woodlands was being higher by 19.2%, 18.5%, and 11.0% than Prosopis thickets; Prosopis + native species stand and open grazing lands, respectively. The seed diversity and richness, recovered from 6-9-cm-deep layer were the highest. On the other hand, the density of Prosopis seeds was the highest in the litter layer. About 156 of seeds/kg (92.9%) of seeds were germinated from cattle fecal matter. However, in a small proportion of seedlings, 12 of seeds/kg (7.1%) were germinated from shot fecal matter. Thus, as the seeds in the soil were low in the study areas, in situ and ex situ conservation of original plants and reseeding of persistent grass species such as Cynodon dactylon, Cenchrus ciliaris, Chrysopogon plumulosus, and Brachiaria ramosa are recommended.

• 한국게임학회 논문지
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• 제6권4호
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• pp.3-16
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• 2006

스토리보드는 대본에서 구상한 장면들을 스케치를 통해 구현하는 과정으로서 말풍선만 없지 만화책과 비슷하다고 말할 수 있다. 스토리보드는 영화나, 애니메이션 및 게임 오프닝 동영상을 구상하는데 도움을 주는데 그렇다면 스토리보드를 제작하기 위해서는 미술가처럼 그림을 잘 그려야 하나? 하고 생각할 수 있겠지만, 히치콕이나 스필버그의 스토리보드를 본다면 그들의 그림 실력이 형편없다는 것을 알 수 있듯이 스토리보드에 있어서 중요한 것은 배우의 움직임(動線)이라 할 수 있다. 그래서 스토리보드를 빠르고 쉽게 만들 수 있는 방법으로 시뮬레이션을 지원하는 디지틸 스토리 보드를 개발해보았다. 디지털 스토리보드를 활용하게 되면 업무의 생산력을 더욱 높일 수 있고 아이디어를 창조하거나 장면(Shot)을 생성하는데 있어서 작업자의 시간을 더욱 소중하게 해줄 수 있다. 또한 인터넷에서 스토리보드를 볼 수 있도록 html문서로 출력 또는 생성할 수 있기 때문에 작업 동료나 고객과 함께 스토리보드를 공유할 수도 있다.

• 한국세라믹학회지
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• 제44권9호
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• pp.529-535
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• 2007

Calcium oxide has been used as a demolition agent in fracturing rocks and old concrete structures, etc. With the agent, demolition work can be done in safety without a noise, vibration and any other pollution, since high expansive pressure is obtained gradually by only mixing the agents with water and pouring the slurry into boreholes. But application of the non-explosive demolition agent is a time-consuming job, especially in winter. Essentially, this problem is related to the reaction rate of calcium oxide with water. This study examines the influence of additives such as cement and anhydrite on expansion pressure of calcium oxide at different curing temperatures. The expansion pressure of calcium oxide began to increase steadily with the rise of the curing temperature. When mixing calcium oxide alone with water, blown-out shot occurred. But as additives were added to calcium oxide, the reaction of calcium oxide delayed and the expansion pressure showed gradual increment. Especially, anhydrite showed a superior delaying effect than cement on the reaction of calcium oxide.

• 한국군사과학기술학회지
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• 제12권1호
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• pp.123-132
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• 2009

Civil petitions and law suits against the military rifle shooting noise have been increased because many military shooting ranges are located near civilian residential area. In order to solve the noise problems, military have devised various methods. In this study, propagation properties of rifle shot through atmosphere were investigated. The military rifle shooting noise level at 5m from muzzle was between $l14{\sim}120dB$ in all directions. The noise level loom both backward and sideward away from system firing range consisting lines of 8 shooting locations were 90dB, when shots were all fired within 10 seconds. At present some of military bases established sound barriers, muzzle enclosures, silencers, and indoor shooting ranges to reduce noises and these prevention methods can reduce noise by $5{\sim}20dB,\;5{\sim}9dB,\;5{\sim}13dB,\;40{\sim}50dB$, respectively. Even though indoor shooting range has the best performance, it requires very expensive construction cost and has short length between target and shooter. In comparison, muzzle enclosure is cheap, but because it is installed in fixed position it can only be used in one shooting position. Therefore a commander should select appropriate methods to reduce military rifle shooting noise considering distance from residential area to the range, mission of military training, budget, etc.