• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.145-145
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• 2012

반도체 집적회로의 집적도가 증가함에 따라 RC delay가 증가하며, 금속 배선의 spiking, electromigration 등의 문제로 인해 기존의 알루미늄 금속을 대체하기 위하여 구리를 배선재료로 사용하게 되었다. 하지만 구리는 실리콘 및 산화물 내에서 매우 빠른 확산도를 가지고 있으므로, 구리의 확산을 막아 줄 확산방지막이 필요로 하다. 이러한 확산방지막의 증착은, 소자의 크기가 작아짐에 따라 via/contact과 같은 고단차 구조에도 적용이 가능하도록 기존의 sputtering 증착 방법에서 이를 개선한 collimated sputter, long-throw sputter, ion-metal plasma 등의 방법으로 물리적인 증착법이 지속되어 왔지만, 근본적인 증착방법을 바꾸지 않는 한 한계에 도달하게 될 것이다. 원자층 증착법(ALD)은 CVD 증착법의 하나로, 소스와 반응물질을 주입하는 시간을 분리함으로써 증착하고자 하는 표면에서의 반응을 유도하여 원자층 단위로 원하는 박막을 얻을 수 있는 증착방법이다. 이를 이용하여 물리적 증기 증착법(PVD)보다 우수한 단차피복성과 함께 정교하게 증착두께를 컨트롤을 할 수 있다. 본 연구에서는 이러한 원자층 증착법을 이용하여 구리 배선을 위한 확산방지막으로 텅스텐질화막을 형성하였다. 텅스텐 질화막을 형성하기 위하여 금속-유기물 전구체와 함께 할라이드 계열인 WF6를 텅스텐 소스로 이용하였으며, 이에 대한 원자층 증착방법으로 이루어진 박막의 물성을 비교 평가하여 분석하였다.

• Korean Journal of Food Science and Technology
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• v.16 no.1
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• pp.108-112
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• 1984

The sorption characteristics of red pepper powder stored at various relative humidity and temperature were studied. At low relative humidity below RH 57%, the sorption equilibrium was easily attained, whereas at higher relative humidity above RH 75%, the powder was browned by higher equilibrium moisture content. The moisture content of monolayer value for the powder was ranging from 11.32% to 12.13% with temperature. First order regression equation of equilibrium moisture content for relative humidity was determined.

• Korean Journal of Food Science and Technology
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• v.14 no.1
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• pp.16-20
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• 1982

The texture changes of potato of the variety ‘Namjack’ were determined as a function of temperature and boiling time by a puncture test with Universal Testing Machine. Apart from texture measurement, heat penetration test and sensory evaluation were carried out. Textural softening during cocking could be expressed by the puncture work and was followed first order kinetics. The Z-value for texture changes was $19.9^{\circ}C$. The cook value in equivalent minutes at $100^{\circ}C$ to get a boiled potatoes was 7 min. Mechanically the boiled product could be regarded as cooked when the final puncture work reduced to the equilibrium value, approximately 6/100 of the initial value.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.36 no.10B
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• pp.1240-1245
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• 2011

In this paper, channel modeling and analysis of wireless visible light communication(VLC) were studied in indoor circumstance. Photons emitted from LED straightly moved and navigated within indoor, after that a part of photons reached on PD via LOS(Line Of Sight) or NLOS(None Line Of Sight). These received signals had characteristics of delay profile and attenuation, which was multiple-path fading. In this paper, computer simulation of VLC channel was executed under the condition that two LEDs were used for transmitter and three PDs were located at different positions of the 20*8*2.3m sized indoor. BER performance simulation was excuted based on the characteristics of each VLC channel.

• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.100-100
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• 2015

자연유역은 주어진 강우에 대해 다양한 형태의 유출반응을 나타내는데, 이는 순간반응함수(Instantaneous Response Function; IRF)로 표현될 수 있다. IRF는 유역의 DEM(Digital Elevation Model)으로부터 지표수 흐름방향을 추출한 뒤 지형분석을 통하여 구한 인자를 이용해 구하는 것이 일반적인 이론이다. 여기서 DEM의 모든 셀에 대해 흐름방향을 부여할 수 있지만, 모든 셀이 하천에 해당하지는 않는다. 따라서 최상류의 셀들은 사면으로, 하류의 셀은 하천으로 구분하여 IRF모의에 적용하게 된다. 사면과 하천은 지표수이송에 전혀 다른 경향을 보이므로 전체적인 유역의 유출반응에 큰 영향을 미친다. 예를 들어 사면과 하천에서의 유속 차이는 IRF의 왜도(skewness)에 주된 영향을 미치는 것으로 알려져 있다 (Botter and Rinaldo, 2003). 하지만, DEM에서 사면과 하천을 정확하게 구분하는 것은 매우 어렵기 때문에 하천시점을 정의하는 데에는 불확실성이 내재되어 있으며, 이러한 점은 추정된 IRF의 불확실성으로 연결된다. 본 연구에서는 하천시점의 불확실성으로 인한 IRF의 불확실성을 정량화하고, 그것의 유의수준을 평가하고자 한다. 이를 위해 다양한 유원면적 기준에 대해 IRF를 계산하고, 그 결과를 심도 있게 고찰한다.

• Proceedings of the Korea Water Resources Association Conference
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• 2023.05a
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• pp.58-58
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• 2023

전 세계 홍수 피해에 노출된 인구가 20년 만에 약 25% 증가한 것으로 나타났는데, 수재해 복구에 드는 비용이 수재해 예방을 위한 비용에 6배에 달했다. 수재해는 비용적인 손실과 아울러 인명피해가 크기 때문에 이를 예방하기 위한 대책 마련이 시급하다. 특히 국내에서 근래 10년간 전체 수재해 중 약 40%가 소하천에서 발생했는데, 이를 해결하는 방안으로 행정안전부와 국립재난안전연구원은 CCTV 기반 자동유량계측기술을 제시했다. 소하천은 홍수도달시간이 매우 짧고 하상이 불규칙하며 표고차가 커 일반적인 수리모형을 이용해 실시간 홍수 예·경보를 위한 홍수량 예측이 어렵다. 또한 대부분의 소하천은 수문 계측이 이뤄지지 않고 있어 하상 특성을 충분히 반영해 홍수량을 산정하기 어려운 문제가 있다. 이에 본 연구에서는 CCTV 기반 자동유량계측기술로부터 수집된 자료들을 이용해 노모그래프를 작성하고 예측강우량만으로 홍수량을 추정해 실시간 홍수 예·경보에 적용할 수 있는 방법을 개발했다. 이때 실시간으로 계측 유량 자료를 반영해 노모그래프를 자동으로 갱신해 예측정확도를 개선할 수 있다. CCTV 기반 자동유량계측기술 검증을 위한 시범 소하천 4개소에 적용한 결과 실시간 자동보정 노모그래프를 이용하면 정확도 향상에 도움을 주는 것으로 나타나 향후 홍수 예·경보를 위한 홍수량 산정에 도움을 줘 수재해를 경감 할 수 있을 것으로 기대된다.

• Journal of Bio-Environment Control
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• v.31 no.3
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• pp.143-151
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• 2022

This study was carried out to investigate quantitative characteristics of the cooling effect in a single-span arch greenhouse with roll-up side vents depending on operation of circulation and exhaust fans during ventilation, in order to suggest a practical strategy regarding installation or operation of forced ventilation systems. The examination was conducted under 3 different ventilation conditions (side vents only, side vents + circulation fans, and side vents + circulation fans + exhaust fans). In each condition, variations of internal and external air temperatures and exogenous environmental factors were recorded during ventilation, and the cooling effects were investigated by comparing the normalized temperature difference (NTD) of each ventilation condition. In the morning time (11:00-12:00), a temporary peak in the temperature difference was observed at the beginning of ventilation regardless of ventilation methods. The time taken to the maximum NTD was decreased from 340 s to 110s, and the NTD was dropped from 1.158 to 1.037 as the more forced ventilation systems were operated. The more operations caused the passing time over specific NTD values reduced by 60% as the time was reduced from 1,030 s to 550 s at NTD = 0.8, 1,610 s to 915 s at NTD = 0.6, and 2,315 s to 1,360 s at NTD = 0.4. The temporary peak in NTD was not observed in the afternoon time (14:00-15:00) but it was dropped as quickly as the ventilation started. Also the more operations resulted in the passing time over specific NTD values reduced by 70% as the time was reduced from 560 s to 345 s at NTD = 0.8, from 825 s to 540 s at NTD = 0.6, and from 1,145 s to 810 s at NTD = 0.4. Conclusively, the intervention of the forced ventilation system is recommended in the morning time or in high thermal conditions to achieve more effective and economical ventilation.

• Korean Journal of Poultry Science
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• v.20 no.2
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• pp.65-72
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• 1993

The experiment was conducted to estasblish the large scale production of anti-serum against chicken IgG and to profile the developmental changes of serum IgG levels during all the feeding period(from hatching to 7 weeks of age) in broiler chicks. Blood sample were taken from Hubbard chicken hi-daily or /and weekly during the experimental period. The pure IgG was isolated from ammonium sulfate treated chicken serum by ion exchange chromatography. The quantitative assay of serum IgG were carried by RID method. It was observed that IgG concentrations were showed the highest at hatching(4.25 $m\ell$/$m\ell$), after that dicreased rapidly, lowest at 2 weeks of age(0.81 $m\ell$/$m\ell$), and gradually increased to 7 weeks of age (2.48 $m\ell$/$m\ell$) There was no differences of IgG level between sex, but the IgG levels of male chicks dicreased more rapidly and increased earlier thereafter than those of females during the first two weeks of agg.

• Journal of IKEEE
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• v.18 no.3
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• pp.409-419
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• 2014

This paper proposes a new temperature control algorithm and system configuration of the pTMS(personal Thermal Massage System). By controlling the pulse width of the PWM(Pulse Width Modulation), the temparature of the heating lamp can be controlled stably, which is indispensable to the massage function. This technology is also adapted to the 'thermal massage', 'thermal acupressure', 'thermal moxibustion' functions of medical equipments. The temperature could be set at between $40^{\circ}C{\sim}70^{\circ}C$ by increments of $5^{\circ}C$, the control could be made in real time by increments of $1^{\circ}C$, and the temperature is displayed on the monitor by triggering every 2 seconds. when the present temperature is equal to the preset temperature, the PWM signal is minimized, and when the present temperature is higher than the preset temperature, overheating is prevented by interrupting the PWM output signal. When the difference of temperature exceeds $4^{\circ}C$, the PWM control is maximized in order for the system to reach the target temperature within a short period of time.

• Food Science and Preservation
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• v.13 no.3
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• pp.337-343
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• 2006

This study was conducted to develop naengmyon added with persimmon leaf powder. To find out the proper mixing ratio, physicochemical properties were investigated. There was a little difference in water binding capacity between control and naengmyon added with persimmon leaf powder. Amylogram showed that initial pasting temperature and peak point value were increased as increment of adding amount of persimmon leaf powder. After cooking, the weight of a naengmyon was increased but cooking loss and turbidity were decreased with increment of persimmon leaf powder. At a glance of color difference values, there was a distinctive boundary near at 6%. But similar at over 6% as increasing adding amount of persimon leaf powder texture characteristics such as hardness, adhesiveness, cohesiveness, springness and gumminess were declined. From overall experimental result, the proper mixing ratio of persimmon leaf powder for naengmyon was 4%.