• 제목/요약/키워드: Active area

검색결과 2,708건 처리시간 0.032초

Evaluation of Humidity Control Ceramic Paint Using Gypsum Binder

  • Lee, Jong-Kyu;Kim, Tae-Yeon
    • 한국세라믹학회지
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    • 제55권1호
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    • pp.74-79
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    • 2018
  • Active clay, bentonite and zeolite were used as porous materials for humidity controlling ceramic boards. The specific area and the pore volume of active clay were higher than those of bentonite and zeolite. It was effective to add white cement as well as a retarding agent to control the setting time of the ceramic paint. As the amount of added porous materials increases, the specific surface area and total pore volume of ceramic paint increase, but the average pore diameter decreases. The addition of porous materials having a high specific area and a large pore volume improves the moisture absorptive and desorptive performance of the ceramic paint. Therefore, in this experiment, the moisture absorptive and desorptive properties were best when active clay was added. Also, as the added amount of porous materials increases, the moisture absorptive and desorptive properties improve. In this experiment, when 70 mass% of active clay was added to ceramic paint, the hygroscopicity was highest at about $80g/m^2$.

10W급 고분자 전해질 연료전지 스택의 구조적 차이에 다른 운전 특성 비교 (Effect of stack configuration on the performance of 10W PEMFC stack)

  • 임성대;김병주;손영준;윤영기;양태현;김창수;김영채
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2009년도 춘계학술대회 논문집
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    • pp.286-286
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    • 2009
  • A small PEM fuel cell has two different stack configurations such as active and passive stacks. The active stack has a distintion of high power density although it makes system complex by using alr blower and related BOPs resulting in large system volume. On the contrary, passive stack has an advantage of compact system because it doesn't need air supplying devices although it reveals relatively low stack power density. In this study we fabricated two 10W PEMFC stacks with different stack configurations, active and passive stacks, and tested their performance and stability. The active stack consists of 13cells with an active area of $5cm^2$. The passive stack has 12cells with an active area of $16cm^2$. When we compared the stack performance of those stacks, the active stack showed higher power density compared to the passive stack, particularly at high voltage regions. However, at low voltage and high current regions, the passive stack performance was comparable to the active stack. The stack stability was largely dependent on the fuel humidity, particularly for active stack. At low humidity conditions, the active stack performance was decreased continuously and the cell voltage distribution was not uniform showing seriously low cell voltage at center cells mainly due to the cell drying. The passive stack showed relatively stable behavior at low humidity and the stack performance was largely dependent on the atmospheric conditions.

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농촌 지역공동체 활성화지역 주민의 공동체특성 - 충남 홍동지역 사례연구 - (Residents' Community Characteristics of a Rural Area with Active Community - Case Study of Hongdong, Chungcheongnam-do -)

  • 정지인;박경옥
    • 한국주거학회논문집
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    • 제26권4호
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    • pp.105-118
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    • 2015
  • The purpose of this study was to give a suggestion for vitalizing rural area's community, with respect to the components of community; 'locality' and 'communality'. The survey was conducted at Hondong, Hodongseong-gun, Chungcheongnam-do, which was a representative area for active rural area community. For the survey, we interviewed an activist on the village in November $9^{th}$, 2014, and let 81 residents fill the questionnaires during March $7^{th}$ to $14^{th}$, 2015. Major findings were as follows. 1) As for the 'locality' factor, the motives of residents' immigration were influenced by the availability of facilities for agriculture education, living, and convenience in the area. Most of residents recognized that the area comprises their own community facility area and expanded area with concentrated facilities of 'li', minimal adminstration unit. It means that their usage pattern of community facilities influences their conceptions of the village. 2) As for the 'communality' factor, original residents and immigrant back-to-farm residents showed different pattern in communicating with neighbors and community facility usages. Residents communicated with neighbors by meeting up or using the concentrated facilities in Gatgol, and visited the Balmak library frequently. Residents' sense of belonging was high with mean 4.16 point of 5.0 in Likert scale.

영역평균 기반의 지오데식 동적 윤곽선 모델에 의한 뇌실 분할 (Segmentation of Brain Ventricle Using Geodesic Active Contour Model Based on Region Mean)

  • 원철호;김동훈;이정현;우상효;조진호
    • 한국멀티미디어학회논문지
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    • 제9권9호
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    • pp.1150-1159
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    • 2006
  • 본 논문에서는 지오데식 동적 윤곽선 모델을 이용하여 뇌실 영역을 검출하기 위하여 기존의 에지지시함수를 대신한 영역 기반의 곡선진행억제 함수를 제안하였다. 제안한 곡선 진행 억제 함수는 뇌실 영역의 검출에 매우 효과적이었으며, 이 함수는 MRI 영상에서 밝게 나타나는 뇌실 영역의 평균 밝기를 기반으로 한다. 본 논문에서는 제안한 방법이 기존의 방법보다 뇌실 영역을 잘 검출할 수 있음을 다양한 척도를 이용하여 수치적으로 비교하였다. 실제 정상과 뇌종양에 의한 뇌질환 영상에 적용시켜 뇌실 검출 과정을 시각적으로 비교하여 우수성을 검증하였다.

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Parametric Active Contour를 이용한 Vehicle Tracking (Vehicle Tracking using Parametric Active Contour)

  • 나상일;이웅희;조익환;정동석
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2003년도 하계종합학술대회 논문집 Ⅲ
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    • pp.1411-1414
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    • 2003
  • In this paper, vehicle tracking is implemented using parametric active contour. Extract objects from the background area is the essential step in vehicle tracking. We focus our algorithm on the situations such that the camera is fixed. However, if a simple and ordinary algorithm is adapted to achieve real-time processing, it produces much noise and the vehicle tracking results is poor. For this reason, in this paper, we propose a parametric active contour model algorithm to achieve better vehicle tracking. Experimental results show that the performance of the proposed algorithm is satisfactory.

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도시쓰레기를 이용한 활성탄의 제조 (Manufacturing of active carbon used city waste)

  • 상희선;타몬 하지메
    • 한국산업융합학회 논문집
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    • 제9권1호
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    • pp.87-91
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    • 2006
  • This research exposes the process of carbonization of solid waste from the city and the method of activated, as well as the process of meso-porous under several test conditions. In addition, it is expected that the active carbon obtained through this process can be used as filter for air and sewage treatment, and can absorb dioxin(as almost 60-80% of meso-porous and porous properties area) unlike the existing active carbon.

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동적 교전 시나리오에서 지상 추적 레이다에 대한 이탈방사체의 효과적 재밍/기만 영역 분석 (Evaluation of Effective Jamming/Deception Area of Active Decoy against Ground Tracking Radars on Dynamic Combat Scenarios)

  • 임재원;이상엽;고일석;백청;이승수
    • 한국전자파학회논문지
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    • 제28권4호
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    • pp.269-278
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    • 2017
  • 플랫폼과 이탈방사체가 동적인 상태에 있는 교전 시나리오에서 지상 추적 레이다에 대한 이탈방사체의 재밍/기만 효과를 분석한다. 플랫폼의 운동과 주변 간섭 유동장에 따른 이탈방사체의 궤적을 6자 유도 운동 방정식을 이용하여 해석한다. 실제적인 교전 시나리오에서 플랫폼과 이탈방사체의 운동 변화 및 이탈방사체의 RF 성능 변화에 따른 지상 추적 레이다에 대한 재밍 성능을 분석하며, 효과적인 지상 추적 레이다 기만을 위한 이탈방사체의 재밍 영역을 도출한다.

이온성 및 양성 계면 활성제가 변압기유의 화학적 특성 및 유동대전에 미치는 영향 (Influence of Interface Active substances(Ionic and Amphoteric) on Chemical property and Streaming Electrification of Transformer Oil)

  • 김용운;이덕출
    • E2M - 전기 전자와 첨단 소재
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    • 제10권7호
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    • pp.719-726
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    • 1997
  • This research was conducted to analyze the change of surface tension, viscosity, streaming current and conductivity of transformer oil when it were injected with the interface active substances.(anionic:S-111, cationic:S-121, amphoteric:S-131) The changes properties of the surface tension and viscosity of the oil which were injected with the interface active substances were divided into the changes area and the minimum reduction area. The surface tension and viscosity of the oil which were injected with three different kinds of interface active substances showed remarkable change at the point where the concentration of the substance in anionic, in cationic and in amphoteric were 100[ppm], 10[ppm] and 1[ppm] respectively. The streaming current and conductivity of the same sample oil were also changed at the same densities of the surface tension and viscosity. For this factor, it was possibile for us to interpret the mechanism of the streaming current and conductivity. Therefore the interface active substances of the three kinds were injected into the oil within the limit of optimal volume, prevention effects of electrification were showed more excellence than unmixed insulating oil.

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지역별 치위생(학)과 학생 및 활동 치과위생사 분포의 추세 분석 (Analysis of distribution trend among students of dental hygiene departments and active hygienists by region)

  • 김영석;정윤숙;김은경
    • 한국치위생학회지
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    • 제23권4호
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    • pp.235-243
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    • 2023
  • Objectives: This study compared the number of graduates in each region for the past 6 years and the number of dental hygienists working in dental clinics by region to evaluate the trend of dental hygienists moving to work areas after graduation. Methods: Health care big data open system_medical manpower statistics, resident population and household status data by year, and education statistics service were used to calculate the number of dentists and dental hygienists, admission status by region, number of dental hygienists per 100,000 population, number of dental hygienists per number of dentists, and distribution of dental hygienists by region. Results: Although the number of active dental hygienists increased in the metropolitan area, the ratio of dental hygienists to dentists did not improve significantly. In addition, the number of students enrolled in provincial universities decreased, and there were fewer active dental hygienists than graduates in provincial areas. Conclusions: Although the number of active dental hygienists increased due to increase in the number of dental hygiene departments, it was found that rural areas did not have a significant impact on the availability of dental hygienists as the graduates moved to the metropolitan area.

Fabrication of Flexible Surface-enhanced Raman-Active Nanostructured Substrates Using Soft-Lithography

  • 박지윤;장석진;여종석
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2012년도 제43회 하계 정기 학술대회 초록집
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    • pp.411-411
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    • 2012
  • Over the recent years, surface enhanced Raman spectroscopy (SERS) has dramatically grown as a label-free detecting technique with the high level of selectivity and sensitivity. Conventional SERS-active nanostructured layers have been deposited or patterned on rigid substrates such as silicon wafers and glass slides. Such devices fabricated on a flexible platform may offer additional functionalities and potential applications. For example, flexible SERS-active substrates can be integrated into microfluidic diagnostic devices with round-shaped micro-channel, which has large surface area compared to the area of flat SERS-active substrates so that we may anticipate high sensitivity in a conformable device form. We demonstrate fabrication of flexible SERS-active nanostructured substrates based on soft-lithography for simple, low-cost processing. The SERS-active nanostructured substrates are fabricated using conventional Si fabrication process and inkjet printing methods. A Si mold is patterned by photolithography with an average height of 700 nm and an average pitch of 200 nm. Polydimethylsiloxane (PDMS), a mixture of Sylgard 184 elastomer and curing agnet (wt/wt = 10:1), is poured onto the mold that is coated with trichlorosilane for separating the PDMS easily from the mold. Then, the nano-pattern is transferred to the thin PDMS substrates. The soft lithographic methods enable the SERS-active nanostructured substrates to be repeatedly replicated. Silver layer is physically deposited on the PDMS. Then, gold nanoparticle (AuNP) inks are applied on the nanostructured PDMS using inkjet printer (Dimatix DMP 2831) to deposit AuNPs on the substrates. The characteristics of SERS-active substrates are measured; topology is provided by atomic force microscope (AFM, Park Systems XE-100) and Raman spectra are collected by Raman spectroscopy (Horiba LabRAM ARAMIS Spectrometer). We anticipate that the results may open up various possibilities of applying flexible platform to highly sensitive Raman detection.

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