• 전력전자학회논문지
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• 제7권2호
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• pp.121-128
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• 2002

새로운 에너지 회수 방식을 채용한 고효율 PDP 구동회로가 제안된다. 제안된 에너지 회수 회로는 PDP의 등가캐패시터에 저장된 에너지를 회수하기 위해서 종래의 에너지 회수 회로에서 부가되었던 별도의 보조 회로 없이 2개의 인덕터 만을 사용하므로 그 구조가 매우 간단하고 시스템 부피가 작으며 적은 수의 전력 소자만으로도 구현이 가능하므로 제작단가 절감효과를 얻을 수 있으며 높은 효율 등의 장점을 가지고 있다. 뿐만 아니라 PDP 화면에서 방사되는 광의 파형이 균일하고 안정적이므로 고화질을 보장하기도 한다. 제안된 회로의 유효성 검증을 위해 전 구간회로를 모두 갖춘 42인치 PDP를 스위칭 주파수 200kHz로 구동한 실험 결과를 제시하며, 본 논문에서 제안된 회로는 차세대 벽걸이형 컬러 TV에 매우 적합하게 적용될 수 있다.

• 한국건축시공학회지
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• 제13권5호
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• pp.457-464
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• 2013

Traditionally, the material used for the form in reinforced concrete construction has been wood or steel. But recently, aluminum forms have been widely used in wall structures such as apartment buildings. Aluminum is light, easy to handle, and economically advantageous, but the hydrogen gas created due to its reaction with the alkali component in concrete gives rise to air pockets on the concrete's surface, and deteriorates the surface's finishability. In this research, to determine the influence of aluminum material on concrete, the cement paste W/C and its chemical reactivity in alkali and acid solution were analyzed. As a prevention plan, the influence of the number of applications of calcium hydroxide and various surface coating materials was analyzed. Through the analysis, it was found that the surface voids on the aluminum form are the result of the reaction of hydrogen gas with an alkali such as $Ca(OH)_2$. This can be prevented by the surface treatment of $Ca(OH)_2$, separating material and coating material. However, poor surface form and damages to the form are expected to cause quality degradation because of the aluminum-concrete interaction. Therefore, thorough surface treatment, rather than the type of separating material or coating material, is considered the most important target of management.

• 한국실내디자인학회논문집
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• 제21권1호
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• pp.148-158
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• 2012

The objective of this study is to find a possible application of small space utilization of GangSo Housing, so called compact-but-effective housing, through analyzing that of Japanese small housing. We analyze openness of view and flexibility of spaces divided by the physical and architectural aspects as first component and the psychological and interior space aspects as second component. The results showed that Japanese small houses have various unit plan compared to uniformity of Korean houses. Openness of view in Japanese small housing is accomplished by letting in light from the outside using position and shape of the window, looking more spacious using courtyard, void spaces, or sliding door hanging from the ceiling, and creating deception of view using floor-wall plan and appropriate materials. Flexibility of spaces is achieved by combination of first and second components, multipurpose of space and furniture, and variety of storage methods. It is necessary to improve spatial efficiency with consideration of volume-metric planing rather than flat-plane and develop various unit plans to meet residents' needs and demands on compact-but-effective houses.

• 생명과학회지
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• 제13권1호
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• pp.42-46
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• 2003

광전용적맥파는 인체의 말초 부위에서 맥파를 검출하는데 널리 이용되고 있으며 심박동수 측정 및 혈액산소포화도 측정에 이용되고 있다. 본 연구는 940 nm의 적외선을 이용한 광전용적맥파를 이용하여 손목에서 요골동맥의 맥파를 기록하였으며 센서의 측정 위치에 따라 맥파의 모양이 다르게 나타나는 것을 관찰하였다. 요골동맥 바로 위의 피부부위에서 기록되는 광전용적파는 손가락 끝에서 기록되는 맥파에 비하여 반전되어있는 특성을 보였다. 반전된 맥파의 발생기전은 센서의 발광부에서 나오는 940 nm의 적외선이 조직에 입사하여 반사되어 나오는 경로의 용적 변화가 심장주기에 따라 일어나지만 손가락 끝부분에 비하여 반대 작용이 있음을 나타낸다. 요골동맥의 바로 위 피하 조직은 심장주기에 따라 동맥의 확장 또는 수축이 발생하면 동맥외벽과 피부 사이 조직에 혈류량의 변화가 일어나며 동맥의 확장 시에는 혈류량이 감소하고 이완시에는 증가되는 특성으로 인하여 반전맥파를 형성하는 것으로 추측된다. 이러한 결과는 요골동맥의 벽에서 적외선 반사가 있음을 시사한다.

• 한국주거학회:학술대회논문집
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• 한국주거학회 2009년도 추계학술발표대회 논문집
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• pp.213-216
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• 2009

The purpose of this study is analyzing temporal flow about 20 detailed performance items in the "Housing Performance Grading Indication System". This study try to figure out situations according grade in detailed performance item and to analyze change item about 112 cases(2 cases in 2006, 15 cases in 2007, 46 cases in 2008, 49 cases in 2009), from January 9, 2006 which system is undertaken, to October, 2009. This system consists of 5 main performance section, 14 performance categories and 20 detailed performance items. 5 main performance parts are Noise and Acoustics(Light-weight impact sound control, heavy-weight impact sound control, sound control of toilet, sound control of party wall), Long-life(flexibility, remodeling & maintenance, durability), Landscape & Indoor Environment(landscape, formaldehyde control & ventilation, daylighting, thermal environment), Welfare & Barrier-free(playground and community center, welfare space, barrier-free design), Fire Safety(fire safety, safe place, fire-resisting quality). Total efficiency about housing can understand systematically of 20 perfomance items though this research.

• 한국해안해양공학회지
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• 제15권4호
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• pp.197-206
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• 2003

최근 특별한 연약지반 처리공법을 적용하지 않고 자중을 감소시키고 구조적인 특성을 이용하여 연약지반 위에 설치하는 방파제가 제안ㆍ개발되고 있다. 본 연구는 이러한 연약지반 방파제의 설계를 위하여 현재 사용하고 있는 중력식 방파제의 설계에서 사용하고 있는 활동, 전도 및 지지력에 대한 안전율 평가 방법을 수정 제안하기 위하여, 다양한 조건의 방파제 형상과 지반조건에 대하여 제안된 방법으로 계산된 안전율과 유한요소해석 결과 얻어진 최대 횡방향 변위를 이용하여 안전율 산정방법의 타당성을 검증하였다. 해석 및 검증 결과, 제안된 안전율 산정방법은 타당한 것으로 나타났다.

• 한국실내디자인학회논문집
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• 제27권3호
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• pp.90-99
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• 2018

The purpose of this study is to study how F.L. Wright reflected the climatic properties and materials of the region into creative ways of designing his architecture. The research method examined the design methods and use of materials by Wright in existing research literature and compares the space plans of housing works in Arizona. The research results will be summarized as follows : 1) For two-story houses, pilotis was used to avoid the hot air and the walls on the ground floor were often planned as thick wall. 2) In the fifties, F.L. Wright's design method changed in a circle from the vertical and horizontal lines. 3) F.L.Wright's Architectural form concepts and design concepts were extracted from local symbolic forms and natural forms. 4) F.L.Wright avoided Arizona's direct light but Indirect sunlight enters into the interior space. 5)External space was expressed as a closed space, while internal space was expressed as an open space. It's like an organic space. 6) Most of the housing materials used are stone and cement from rough deserts, and wood with low heat conductivity and thick concrete blocks to prevent the sunlight from rising above.

• 터널과지하공간
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• 제20권3호
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• pp.183-193
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• 2010

이 논문은 석회석 광산의 발파 중에 일어나는 파쇄도 관련 문제들에 대하여 고찰한 것이다. 먼저 실 규모 발파 시에 발파 결과를 크게 달리 할 수 있는 중요 발파설계변수를 추출하였다. 또 현장에서 간편하게 적용할 수 있는 발파 성과 평가 방법을 제시하였다. 이는 저자들이 시멘트 제조를 위한 석회석 광산에서 다양한 규모로 설계, 시공, 평가 한 경험에 근거한 것이다.

• 대한기계학회논문집B
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• 제23권11호
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• pp.1473-1480
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• 1999

In the case of Impingement of plane moving shock wave over concave or convex double wedges (pseudo-stationary flow) and cylindrical walls (truly non-stationary flow), it Is expected that there are transitions from regular reflection to Mach reflection or vice versa In shock wave reflections. In these connections, it is necessary to verify the various of reflection process and transition angle for the reflection problems In double wedges, and to verify the transition angle, effects of curvature radius and initial wall angle on it for the reflection problems In cylindrical walls. Especially, we focused our attention to confirm the existence of hysteresis phenomenon induced by the different transition processes, and Neumann paradox, which is a small discrepancy between theoretical and experimental transition angles. Experiments were carried out by using the shock tube of $6{\times}6cm^2$, and high speed photographic technique consisted of delay unit, triggering system, light source of Xe lamp and so on was used for flow visualization.

• 한국정밀공학회지
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• 제21권4호
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• pp.57-63
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• 2004

This paper describes a method for digitizing the compound surfaces which are comprised of several unknown feature shapes such as base surface, and draft wall. From the reverse engineering's point of view, the main step is to digitize or gather three-dimensional points on an object rapidly and precisely. As well known, the non-contact digitizing apparatus using a laser or structured light can rapidly obtain a great bulk of digitized points, while the touch or scanning probe gives higher accuracy by directly contacting its stylus onto the part surface. By combining those two methods, unknown features can be digitized efficiently. The paper proposes a digitizing methodology using the approximated surface model obtained from laser-scanned data, followed by the use of a scanning probe. Each surface boundary curve and the confining area is investigated to select the most suitable digitizing path topology, which is similar to generating NC tool-paths. The methodology was tested with a simple physical model whose shape is comprised of a base surface, draft walls and cavity volumes.