• 제목/요약/키워드: arc function

검색결과 321건 처리시간 0.029초

Microstructure of the antennal sensory organs in female millipede Oxidus gracilis (Polydesmida: Paradoxomatidae)

  • Chung, Kyung-Hwun;Moon, Myung-Jin
    • Animal cells and systems
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    • 제15권1호
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    • pp.53-61
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    • 2011
  • The fine structural characteristics of the antennal sensory organs of a female millipede Oxidus gracilis (Polydesmida: Paradoxomatidae) were observed with both field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM). We could identify four apical cones and three basic types of antennal sensillae in a. gracilis as follows: chaetiform sensilla (CS), trichoid sensilla (TS) and basiconic sensilla (BS). Of these, both types of CS and TS can be observed throughout all antennal segments except the terminal 8th article, whereas the BS are observed within the cuticular depressed regions of the articles from the 5th to the 7th segment. According to their relative microstructure and location, the BS arc divided further into three subtypes: large ($BS_1$) small ($BS_2$) and spiniform ($BS_3$). The $BS_1$ can be seen on the 5th article only, while $BS_2$ can be seen on the 5th and 6th articles. The $BS_3$ is characteristically seen within the depressive region of the 7th article. Both the CS and TS of O. gracilis are similar in structure, and they are related to the function of mechanical reception; however, four large apical cones (AP) and three subtypes of BS are likely to function in gustatory and olfactory reception.

GIS를 이용한 아산시 마을습지 인벤토리 구축 및 관리 방안 연구 (A Study on Development of Village Wetlands Inventory Using GIS and Establishment of Management Methods in Asan City, Korea)

  • 박미옥;양승빈;구본학
    • 한국환경복원기술학회지
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    • 제18권6호
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    • pp.167-177
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    • 2015
  • This study was conducted to establish an inventory and propose conservation strategies for 'village wetlands' in Asan city, Korea, using GIS. As results, the village wetlands are defined as such places as 'palustrine' wetland, village embankment, agricultural reservoir or small reservoirs located in or near the village and related to everyday life or farming. Firstly 807 provisional village wetlands(draft) were identified in Asan by using Arc-GIS 10.1, then 196 wetlands(final) were defined finally as village wetlands and listed the inventory of Asan Village Wetlands after being validated through office works and field survey. The office works analyzed minimum area(greater than $625m^2$), satellite images, the Korea Land Information System, land use map and land coverage map. To evaluate the function and conservation values, the 37 wetlands were selected for detailed surveying and function assessment based on the following criteria : 1) doubled code both wetland and reservoir at digital map, 2) located less than 100m from village and 3) ecologically connected to such ecological resources as seaside mudflats, mountains and green area and ecological passages for small size wildlifes. As the result of the wetland function assessments by the RAM method, 7 wetlands were found to have 'high' wetland function (conservation) 18 wetlands were 'medium' (enhancement) and 12 wetlands were 'low' (restoration or enhancement). Enhancing biodiversity and ecosystem services through ecological management of wetlands in Asan and connecting with the Ecological Natural Degree were proposed.

세장비가 큰 타원형 컵 성형 공정의 다단계 유한요소 역해석 (Multi-stage Finite Element Inverse Analysis of Elliptic Cup Drawing Processes with the Large Aspect Ratio)

  • 김승호;김세호;허훈
    • 소성∙가공
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    • 제9권3호
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    • pp.304-312
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    • 2000
  • An inverse finite element approach is employed to efficiently design the optimum blank shape and intermediate shapes from the desired final shape in multi-stage elliptic cup drawing processes. The multi-stage deep-drawing process is difficult to design with the conventional finite element analysis since the process is very complicate with the conventional finite element analysis since the process is very complicated with intermediate shapes and the numerical analysis undergoes the convergence problem even with tremendous computing time. The elliptic cup drawing process needs much effort to design sine it requires full three-dimensional analysis. The inverse analysis is able to omit all complicated and tedious analysis procedures for the optimum process design. In this paper, the finite element inverse analysis provides the thickness strain distribution of each intermediate shape through the multi-stage analysis. The multi-stage analysis deals with the convergence among intermediate shapes and the corresponding sliding constraint surfaces that are described by the analytic function of merged-arc type surfaces.

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30AF 차단기 순시 Trip 동작 특성분석을 통한 저압차단기의 안전성 개선방안 (A Safety Improvement of Low Voltage Circuit-breakers through Analysis of Instantaneous Trip Characteristics of 30AF Circuit-Breakers)

  • 김주철;임정균;이상중
    • 조명전기설비학회논문지
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    • 제24권12호
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    • pp.78-83
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    • 2010
  • The domestic 30AFs that are currently being produced show many problems due to different instantaneous trip characteristics in case of short-circuit. The troubles may cause explosion by excessive short-circuit capacities and arc emission, which results in a wide range of blackout. The function and safety of the low voltage circuit breakers installed before the end load are very important. This paper presents an idea on the safety improvement of the low voltage circuit-breakers through the analysis of instantaneous trip characteristics of domestic 30AF circuit-breakers.

아크고장 진단기능을 고려한 지능형 분전반의 단상 전력관리 모듈 설계에 대한 연구 (The Development of the Single-Phase Electric Power Information Management Module of the Intelligent Electrical Switchgear Panel with Arc Fault Diagnosis function)

  • 고윤석;이서한;최현철;이한찬
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2009년도 제40회 하계학술대회
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    • pp.2255_2256
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    • 2009
  • 주택용 분전반내의 과부하 차단기(MCCB)나 누전차단기(ELCB)들은 전류 RMS 크기만을 가지고 고장전류를 인식하기 때문에 아크고장전류를 차단하지 못해, 수용가들은 전기화재로 인한 심각한 인명피해나 재산상의 손실을 자주 경험할 수 있다. 따라서 본 연구에서는 이러한 문제를 해소하기 위해 아크진단 기능을 가지는 지능형 분전반을 제안하고자 한다. 특히 여기에서는 아크고장 진단 기능을 고려한 지능형 분전반의 단상 전력관리 모듈 설계연구를 주 목적으로 한다.

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안정동력학에 의한 가변수요 통행배정모형 (A Variable Demand Traffic Assignment Model Based on Stable Dynamics)

  • 박구현
    • 한국경영과학회지
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    • 제34권1호
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    • pp.61-83
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    • 2009
  • This study developed a variable demand traffic assignment model by stable dynamics. Stable dynamics, suggested by Nesterov and do Palma[19], is a new model which describes and provides a stable state of congestion in urban transportation networks. In comparison with the user equilibrium model, which is based on the arc travel time function in analyzing transportation networks, stable dynamics requires few parameters and is coincident with intuitions and observations on congestion. It is therefore expected to be a useful analysis tool for transportation planners. In this study, we generalize the stable dynamics into the model with variable demands. We suggest a three stage optimization model. In the first stage, we introduce critical travel times and dummy links and determine variable demands and link flows by applying an optimization problem to an extended network with the dummy links. Then we determine link travel times and path flows in the following stages. We present a numerical example of the application of the model to a given network.

연료전지에 의해 구동되는 용접기용 단상 컨버터 설계 (Single Phase Converter Design for Fuel Cell Based Welding Machine)

  • 민명식;박상훈;박소리;원충연
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2008년도 하계학술대회 논문집
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    • pp.624-627
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    • 2008
  • It is generally used the boost converter for the welding machine using fuel cell. But this type generates the duplicate loss between boost converter and inverter. As a result, the whole efficiency is lower than conventional inverter arc welder and the cost is expensive due to additional switching device. Therefore, we proposed the inverter rectification type DC-DC converter with boost converter function in fuel cell based TIG welder. The performance of the proposed technique is evaluated on a 1.2kW fuel cell stack based experimental prototype circuit.

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방향성 판단기능 부가된 아크 고장검출차단기의 오동작 제거 (Eliminating unwanted operation of Arc Fault Circuit Interrupter with the directivity judgement function)

  • 이희철;강창원;신봉일;김영노
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2006년도 제37회 하계학술대회 논문집 D
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    • pp.1917-1918
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    • 2006
  • 아크 고장검출차단기(Air Fault Circuit Interrupter)는 전기배선에 있어서 노화, 절연파괴등 아크를 검출하여 전기화재를 미연에 방지해준다. 반면 여러가지 아크성 신호가 혼재되어 있어 유사 아크로 인해 유해 아크만을 검출하지 못하여 오동작하게 된다. 따라서 아크전류를 검출하기 위해서는 아크전류와 혼동되는 많은 신호들을 분석할 필요가 있으며, 이러한 전기 기구에서 발생하는 노이즈와 전기 도선에서 발생한 아크 전류를 분류하여 전기 도선에서 발생하는 유해 아크 전류만을 검출하여 차단하도록 설계하였다.

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철도차량용 유리섬유직물/페놀릭 복합재의 가속노화 특성 (Aging Characteristics of Glass Fabric/Phenolic Composites in Train Carbody)

  • 윤성호;남정표;황영은;신광복
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2004년도 춘계학술대회 논문집
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    • pp.352-357
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    • 2004
  • In this study. the effects of combined environmental factors on mechanical and thermal analysis properties of graphite/epoxy composites were evaluated through a 2.5KW accelerated environmental aging tester. Environmental factors such as temperature. moisture, and ultraviolet were considered. A xenon-arc lamp was utilized for ultraviolet light. and exposure times of up to 3000 hours were applied. Several types of specimens - tensile, bending, and shear specimens those are warp direction and fill direction were used to investigate the effects of environmental factors on mechanical properties of the composites. The glass fabric $\sharp$650/AP300 was used for the fabrication of specimens. Mechanical degradations for tensile, bending and shear properties were evaluated through a UTM. Also. storage shear modulus. loss shear modulus, and tan $\delta$ were measured as a function of exposure times through a dynamic mechanical analyzer. Finally exposed surfaces of the composites were examined using II scanning electron microscope.

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GIS를 이용한 원예단지의 Database 구축 및 활용 (Establishment and Utilization of Horticulturalfield management system)

  • 신영철;안상현
    • 한국농촌계획학회:학술대회논문집
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    • 한국농촌계획학회 1998년도 정기총회 및 춘계 학술논문발표회
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    • pp.15-16
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    • 1998
  • It was studied Horticultural field by ARC/lNFO software, applicated on GIS- management information system, which dealt with graphic and attribute data together. This result obtained was summarized as follow : 1. It would be to output about position, attribute and photographic data of this horticultural farm through AML. 2. It would be easy to use with internal interface which is composed in basic function menu and application menu. 3. It would be good to plant Water melon and Tomato in this Horticultural farm. 4. The method which applicated overlay and analysis would be need to manage farming data in this horticultural farm and to develop a dynamic decision support system interfaced with GIS.

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