• 한국연소학회:학술대회논문집
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• 한국연소학회 2012년도 제45회 KOSCO SYMPOSIUM 초록집
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• pp.159-162
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• 2012

Combustion in a narrow space has been interested as a model of meso-scale combustors (or micro-combustors). Premixed flames have been used to overcome flame quenching in a narrow space and non-premixed flames have been used to improve flame stabilization. In this study, overall characteristics of premixed flame and non-premixed flame in narrow combustion spaces were reviewed. Various effects such as the flow velocity distribution, thermal interaction, enhanced mass diffusion were discussed and an eventual structure of the flame at the extinction limit was introduced.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1995년도 추계학술발표회논문집(2)
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• pp.574-579
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• 1995

Saturated boiling heat transfer experiment in a hemispherical narrow space is conducted using Freon-113 to investigate an additional heat removal capability through a hypothetical gap between lower head and degraded core. The narrow space of 1mm consists of a 124mm diameter heated stainless steel hemisphere and a glass outer vessel. Within the hemispherical narrow space large coalesced bubbles are produced and these bubbles rise in random direction, causing liquid flow in from the opposite side to fill the region. Such flow in random direction makes the flow field in the narrow space very chaotic and thus enhance heat transfer. The heat transfer coefficient is higher at lower angle and at higher heat flux. The present study shows that the liquid from upper region can effectively penetrate into the gap and augment the heat removal capability through tile gap.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회A
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• pp.1173-1178
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• 2007

The robot for narrow space is used in searching, investigating or cleaning. Up to now variety of researches on in-pipe robots have been introduced. However it is still hard to overcome vertical or curved passage. In most cases of narrow space robots are able to travel just aimed diameter which was selected when those are developed. Also, a large percentage of robots are not able to detect the configuration of pipe or circumstance. In this paper we present a robot called PAROYSⅡ for narrow space with vertical and curved passage. This proposed robot is not affected at all to variance of pipes, vertical or horizontal passages, curved pipes, projecting parts and parallel planes. In addition to that, it will perceive the internal configuration of pipe and terrain, which will be not only available to control navigating scheme by itself, but also mappable about the passage which the robot traveled. Core points in the design and structure are introduced and preliminary verification is given.

• 천문학회보
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• 제43권1호
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• pp.49.2-49.2
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• 2018

Flux calibration for narrow band photometric data gives us an opportunity to get a line flux of extended targets. We developed flux calibration processes for narrow band photometry using broad band filters as a continuum indicator. We derived parameters for color correction and zero point correction including color terms. Applying our method, we successfully subtracted continuum emissions and calibrated the emission lines from an FU Ori type object, V960 Mon.

• Journal of Power Electronics
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• 제13권4호
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• pp.647-655
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• 2013

In this paper, an approach to reduce the common-mode voltage and to eliminate narrow pulse for implemented AC-DC matrix converters is presented. An improved space vector modulation (SVM) strategy is developed by replacing the zero space vectors with suitable pairs of active ones. Further, while considering the commutation time, the probability of narrow pulse in the conventional and proposed SVM methods are derived and compared. The advantages of the proposed scheme include: a 50% reduction in the peak value of the common-mode voltage; improved input and output performances; a reduction in the switching loss by a reduced number of switching commutations and a simplified implementation via software. Experimental results are presented to demonstrate the correctness of the theoretical analysis, as well as the feasibility of the proposed strategy.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2012년도 제44회 KOSCO SYMPOSIUM 초록집
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• pp.9-12
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• 2012

In this study, opposed flow combustion was re-visited in a narrow channel. Various flame behaviors were observed. Due to the confined structure of the combustor in this study, flame structures at very narrow strain rate could be stabilized and their characteristics were investigated. This study will be helpful to understand overall flame behavior of non-premixed flame in a narrow combustion space, and will also be useful to develop small combustors.

• 한국재난정보학회 논문집
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• 제12권4호
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• pp.342-349
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• 2016

본 연구에서는 협소거주공간에 대해 이해하고 대표적인 협소 거주공간인 고시원, 노래방 등에 대한 설문 및 실태조사와 과거 관련 사고사례 조사 및 분석을 통해 협소 거주공간의 화재 위험 특성을 분석하였다. 고시원과 노래방은 업종 특성상 구획된 실의 밀폐되고 복잡한 통로 구조를 가지고 있다. 또한 노래방의 경우 지하층에 위치하여 있어 화재 발생 시 환기 및 배연이 잘 이루어지지 않고 피난로가 복잡하여 제한적인 구조를 가지고 있다. 특히 고시원은 독립적이고 폐쇄적인 공간적 특성을 가지고 있어 화재 진압에 큰 어려움을 가지고 있다. 그러므로 협소 거주공간의 구조물 특성에 적합한 소방설비의 설치와 특수한 구조적 형태 및 환경에 적합한 특수 장비(화원 탐지, 요구조자 구조 등) 및 화재 진압 전술에 대한 연구개발이 요구된다.

• 한국정보전자통신기술학회논문지
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• 제10권3호
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• pp.242-248
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• 2017

최근 급속한 경제성장에 따른 인구의 도시 집중화 현상이 발생하고 있으며 이로 인해 도시 건물의 밀집화, 고층화, 용도의 다변화에 따라서 화재 및 사고 범죄의 위험이 상당히 증가하는 추세이다. 이런 협소거주공간은 무창층의 특성을 가지고 있어 화재 발생시 급격한 연기확산 속도에 따른 거주자의 피해가 큰 게 현실이며 소방작전에 사용되는 무선통신의 전파 투과율 및 송달거리 또한 건축자재 및 건축물의 형태에 따라 통신 성능의 차이가 발생한다. 따라서 효율적인 소방작전을 위해 본 논문에서는 협소거주 공간의 건물 자재(철근콘크리트벽체, 샌드위치 패널 벽체, 경량칸막이 석고보드 벽체, 유리 출입문, 방화철문) 및 구조 특성을 분석하고 이에 따른 무선 통신의 전파(주파수 대역 424MHz, 2.4GHz) 투과율 및 송달거리 측정실험을 통해 최적의 소방작전을 위한 협소거주 공간의 통신 환경 솔루션을 도출하였다.

• 한국환경복원기술학회지
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• 제18권2호
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• pp.33-44
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• 2015

This study was performed to propose the site selection plan for the restoration of the target Narrow-mouth Frog(Kaloula borealis) habitat, and has developed the AHP model to select the optimal site for narrow-mouth frog habitat restoration on the basis of the narrow-mouth frog Habitat Suitability Index (HSI) items (factors and variables). The assessment areas were established by the narrow-mouth frog HSI factors such as space, feed, cover, water(breeding), threatening factors and others, and the sub-assessment items by each assessment area were established based on the narrow-mouth frog HSI variables. The weighting values of the assessment areas and items were calculated by the developed AHP method. The weighting values of the 5 assessment areas were arranged in order as cover(0.283), water(breeding)(0.276), feed(0.230), space(0.147), and threatening factor(0.064). The final weighting values of the 14 assessment items were arranged in order of height as low-rise grassland(0.190), soil quality(0.178), and stones and between the stones(0.105). The scoring criteria according to the assessment items and factors were marked and applied by equal intervals considering the criteria by HSI items of the narrow-mouth frog and finally the scoring criteria diagram has been proposed for the optimal site selection of the narrow-mouth frog habitat restoration.

• 한국실내디자인학회논문집
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• 제21권5호
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• pp.23-33
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• 2012

This study evaluated two educational spaces, one middle school and one high school in point of universal design. The survey method with an observation and measuring method was used. The subject were 238 students of a middle and a high school. They evaluated their schools according to 53 universal design related items which consisted of 5 principles. Findings were as follows ; 1) The width of passage between desk and desk was very narrow and there is the threshold at the door of classroom. The students evaluated them negatively, too. Also, they indicated that the size of individual locker was small and the corner of furniture was sharp. 2) The width of door and passage was narrow and the floor was not flat in restroom. The design quality such as color and finishes was not good. Also, the students evaluated all these items negatively. 3) The dining space was too big. That is, so many students takes meals in one big space. The dining tables were arranged in a long rows and the width between them was also so narrow to pass through. 4) The student of high school evaluated their educational environments more negatively than ones of middle high school. This means that the high school students were more dissatisfied with their school environment. The educational environment should be designed on the base of their students' needs.