• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1995년도 추계학술대회 논문집
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• pp.343-346
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• 1995

In this paper, the effect of alkaline oxides on the humidity sensitivity of $V_2O_{5}$(2mol%)-doped $TiO_2$(98mol%) was investigated as functions of $Li_{2}Co_{3}$, $Na_{2}Co_{3}$. III-1. Measurement of Density. When the mole% of $Li_2$O is varied 0,1,2,5mol%, the more the mole% of additives is increased, the more difference of bulk and apparent density is largely narrowed. The difference of two densities of sample containing 2mol% $Na_2O$ was large all the moat. The sample containing 1mol% $Na_2O$ was small most. III-2. Observation of porosity. The porosity and total intrusion volume according to various amounts of $Li_2O$ was reduced and those of sample containing 2mol% $Na_2O$ as 31.13%, 0.1155mL/g was the highest and 1mol% $Na_2O$ was lowed most and 5, 10mol% $Na_2O$ was more high compare with sample without alkaline oxides. III-3. Characteristic of humidity sensitivity. 1. Impedance of samples containing $Li_2O$ was high compare with sample without alkaline oxides, so we thought it showed Poor sensitivity because it have no impedance changing rapidly as function of relative humidity. 2. When the humidity was increasing from 30RH% to 90RH%, the impedance of sample containing 2mol% $Na_2O$ at 120HZ changed exponential rapidly from 6${\times}$$10^{7}$$\Omega$) to 1.25${\times}$$10^4$$\Omega$. At under 50RH% and over 50RH%, the humidity sensitivity of samples containing 2mol% $Na_2O$ was best especially in the range of the low humidity. III-4. Characteristic of TG curves. When algal me oxide $M_{2}CO_{3}$(M=Li, Na) were added into $V_{2}O_{5}$-doped $TiO_2$, the stability of humidity sensitivity of samples containing amounts of $Li_2O$ was unstable. The samples containing 1mol% $Na_2O$ was unstable.

• KIEAE Journal
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• 제7권5호
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• pp.87-92
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• 2007

As expansion of balconies at apartments has been legalized, the major function of the balconies as a thermal buffer zone is disappearing. This weakens the ability of window to insulate heat and multiplies surface condensation. Thus more and more residents require solutions to increasing surface condensation and aggravation in thermal comfort. This study intends to provide basic data by evaluating performance of triple layered Low-E windows, triple layered clear windows, double layered Low-E windows and double layered clear window used for expanded balconies and marketed within the country in terms of surface condensation and thermal environment through simulation. Results revealed that no surface condensation occurred at double layered Low-E windows and triple layered Low-E windows. Surface condensation took place at double layered clear windows and triple layered clear windows at a relative humidity of 60%. Thermal environment analysis suggested that double layered clear windows showed the most time falling into the range of comfort at $23^{\circ}C$. The figure were $22^{\circ}C$ for triple layered clear windows, $22^{\circ}C$ for double layered Low-E windows and $21^{\circ}C$ for triple layered Low-E windows.

• 한국산림과학회지
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• 제103권3호
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• pp.368-374
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• 2014

본 연구는 에틸렌 처리와 저장조건에 따른 '오텀센스' 다래의 저장성과 품질 변화를 조사하기 위하여 수행하였다. 다래의 저장 중 품질변화를 관찰한 결과, 48시간과 96시간동안 에틸렌을 처리한 모든 처리구에서 경도는 저장기간이 경과함에 따라 급격히 감소하였으나, 당도는 급격히 증가하였다. 산도는 모든 처리구에서 0.7~1.4%수준으로 나타났다. 저장기간 동안 다래의 중량감소율을 조사한 결과, 48시간동안 에틸렌을 처리하고 저장한 다래는 저장 24일 동안 $20^{\circ}C$저장구에서 30.9%로 가장 높았으며, $2^{\circ}C$에 상대습도 90%저장구에서 5.9%로 가장 낮게 나타났다. 96시간동안 에틸렌을 처리하고 저장한 다래는 저장 22일 동안 $20^{\circ}C$저장구에서 29.4%, $4^{\circ}C$저장구에서 20.7%, $2^{\circ}C$저장구에서 12.1% 그리고 $2^{\circ}C$에 상대습도 90%저장구에서 6.0% 감소하였다. 저장기간 동안 다래의 식미는 모든 처리구에서 증가하다 감소하였다. 특히 $20^{\circ}C$저장구는 저장 초기에 급격히 증가하다 감소하였고, $2^{\circ}C$에 상대습도 90%저장구는 저장 18일 후에 감소하였다. 부패율은 모든 처리구에서 저장기간 동안 증가하였으며, $20^{\circ}C$저장구는 저장 2일 후, $2^{\circ}C$에 상대습도 90%저장구는 16일부터 급격히 증가하였다. 따라서, $2^{\circ}C$에 상대습도 90%의 저장조건이 다래의 품질을 유지하는데 효과적일 것으로 판단되며, '오텀센스' 다래의 적정 저장조건과 후숙시기를 판단할 수 있을 것이라 생각된다.

• 한국대기환경학회지
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• 제33권6호
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• pp.616-625
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• 2017

Measurements using five real-time particle samplers were compared to measurements using three NRM (National Reference Method system) filter-based samplers(Gravimetric method) at Incheon, Korea, between May and August, 2014. The purpose of this study was to suggest the quality assurance/quality control (QA/QC) method of each instrument for use in a real-time continuous particle sampler to measure the mass of airborne particles with an aerodynamic diameter less than $2.5{\mu}m$ ($PM_{2.5}$). Five real-time particle samplers of BAM1020, FH62C_14, TEOM, PM-711 and SPM-613 were evaluated by comparing its measured 23 hr average $PM_{2.5}$ concentrations with those measured with NRM filter-based samplers simultaneously. The parameters(e.g. Inlet heating condition, Slope factor, Film response, Intercept, Background, Span value) of the real-time samplers were optimized respectively by conducting test performance evaluation during 7 days in field sampling. For example, inlet heating temperature of TEOM sampler controls $35{\sim}40^{\circ}C$ to minimize the fluctuation of the real-time measurement data and background value of BAM1020 is the key factor affecting the accuracy of $PM_{2.5}$ mass concentration. We classified the $PM_{2.5}$ concentration according to relative humidity (80%) to identify water absorbed in aerosols by measuring the ${\beta}$-ray samplers(BAM1020, FH62C_14) and TEOM. ${\beta}$-ray samplers were not strongly affected by relative humidity that the difference of the average $PM_{2.5}$ concentration was about 5%. On the other hand, The TEOM sampler overestimated $PM_{2.5}$ mass concentration about 15% at low relative humidity (<80%).

• International Union of Geodesy and Geophysics Korean Journal of Geophysical Research
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• 제25권1호
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• pp.57-81
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• 1997

Numerical prediction of nocturnal thermal high in summer of the 1995 near Taegu city located in a basin has been carried out by a non-hydrostatic numerical model over complex terrain through one-way double nesting technique in the Z following coordinate system. Under the prevailing westerly winds, vertical turbulent fluxes of momentum and heat over mountains for daytime hours are quite strong with a large magnitude of more than $120W/\textrm{m}^2$, but a small one of $5W/\textrm{m}^2$ at the surface of the basin. Convective boundary layer (CBL) is developed with a thickness of about 600m over the ground in the lee side of Mt. Hyungje, and extends to the edge of inland at the interface of land sea in the east. Sensible heat flux near the surface of the top of the mountain is $50W/\textrm{m}^2$, but its flux in the basin is almost zero. Convergence of sensible heat flux occurs from the ground surface toward the atmosphere in the lower layer, causing the layer over the mountain to be warmed up, but no convergance of the flux over the basin results from the significant mixing of air within the CBL. As horizontal transport of sensible heat flux from the top of the mountain toward over the basin results in the continuous accumulation of heat with time, enhancing air temperature at the surface of the basin, especially Taegu city to be higher than $39.3^{\circ}C$. Since latent heat fluxes are $270W/\textrm{m}^2$ near the top of the mountain and $300W/\textrm{m}^2$ along the slope of the mountain and the basin, evaporation of water vapor from the surface of the basin is much higher than one from the mountain and then, horizontal transport of latent heat flux is from the basin toward the mountain, showing relative humidity of 65 to 75% over the mountain to be much greater than 50% to 55% in the basin. At night, sensible heat fluxes have negative values of $-120W/\textrm{m}^2$ along the slope near the top of the mountain and $-50W/\textrm{m}^2$ at the surface of the basin, which indicate gain of heat from the lower atmosphere. Nighttime radiative cooling produces a shallow nocturnal surface inversion layer with a thickness of about 100m, which is much lower than common surface inversion layer, and lifts extremely heated air masses for daytime hours, namely, a warm pool of $34^{\circ}C$ to be isolated over the ground surface in the basin. As heat transfer from the warm pool in the lower atmosphere toward the ground of the basin occurs, the air near the surface of the basin does not much cool down, resulting in the persistence of high temperature at night, called nocturnal thermal high or tropical night. High relative humidity of 75% is found at the surface of the basin under the moderate wind, while slightly low relative humidity of 60% is along the eastern slope of the high mountain, due to adiabatic heating by the srong downslope wind. Air temperature near the surface of the basin with high moisture in the evening does not get lower than that during the day and the high temperature produces nocturnal warming situation.

• 보존과학회지
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• 제34권5호
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• pp.387-396
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• 2018

국내 목조건축문화재는 자연환경에 그대로 노출되어 있어 생물피해와 여러 환경요인에 의해 피해가 가속화되고 있다. 이에 본 연구에서는 보은 법주사와 순천 선암사에 기상인자 모니터링을 위한 자동기상측정장비를 설치하여 기상데이터를 수집하였다. 이들 데이터에 통계 모형을 적용하여 기상인자를 예측하고 기상인자별 예측성능을 비교하였다. 그 결과, 법주사와 선암사 두 곳 모두에서 대기온도와 이슬점온도의 상관계수가 0.95 이상으로 가장 높게 나타났으며 상대습도의 상관계수는 0.65로 낮게 나타났다. 결과적으로 일반선형모형은 대기온도와 이슬점온도를 예측하기에 적합하다는 것을 확인하였다. 기상인자들 사이의 상관성을 분석한 결과, 법주사와 선암사 모두 대기온도와 이슬점온도, 일사량과 증발량 사이에 강한 양의 상관성을 보였으며, 법주사에서는 대기온도와 증발량이 약한 양의 상관성을 나타내었고 선암사에서는 풍속이 대기온도와 상대습도에 대하여 약한 음의 상관성을 나타내었다. 선암사의 풍속은 겨울에 높고 여름에 평균 이하로 낮아지는 패턴을 보이는데, 이것은 대기온도와 상대습도가 높은 여름철에 수분의 증발을 막고 정체시키는 역할을 하는 것으로 판단되며, 결과적으로 이것이 선암사의 목조건축물 피해를 가속화시키는 것으로 판단된다.

• Applied Biological Chemistry
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• 제21권3호
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• pp.144-149
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• 1978

양조(釀造)간장을 분무건조(噴霧乾燥)에 의하여 분말화(粉末化)하고 포장(包裝)하지 않은 분말(粉末)간장과 포장제품(包裝製品)의 수분흡착특성(水分吸着特性)을 $30^{\circ}C$에서 포화(飽和) 염용액(鹽溶液)을 사용(使用)하여 각상대습도(各相對濕度)에 따라 시험(試驗)하였으며 얻어진 결과(結果)를 요약(要約)하면 다음과 같다. 18.3%의 수분(水分)을 함유(含有)한 분말(粉末)간장의 평형수분함량(平衡水分含量)은 52%였으며, 포장(包裝)된 분말(粉末)간장 제품(製品)의 평형수분함량(平衡水分含量)은 낮은 상대습도(相對濕度)에서 감소(減少)되는 반면(反面)에 높은 상대습도(相對濕度)에서 급격(急激)히 증가(增加) 하였다. 분말(粉末)간장의 흡습속도정수(吸濕速度定數) K는 $311.4{\times}10^{-5}/hr$인 반면(反面)에 필름으로 포장(包裝)한 제품(製品)의 K'는 투습도(透濕度)가 높을수록 높았다. 포장제품(包裝製品)의 안전저장기간(安全貯藏期間)을 $38^{\circ}C$. 92% R. H.의 극한조건(極限條件)에서 Brown식(式)에 의(依)해 산출(算出)한 결과(結果), 필름의 투습도(透濕度)가 낮은 Al. foil/P.E.가 164일(日)로서 가장 길었고 P.V.C. 포장(包裝)은 18일(日)로서 가장 짧았다.

• 생물환경조절학회지
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• 제30권1호
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• pp.72-76
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• 2021

풍속에 따른 증발산량(수분흡수량)은 노랑조팝, 송악, 수호초 모두 같은 경향을 나타내었다. 세 식물 모두 4m·s-1의 강풍에서 가장 높은 수분흡수양상을 보였으며 풍속이 낮아질수록 수분흡수량도 함께 감소하는 경향을 보였다. 풍속처리없이 플라스틱 하우스 내의 기본 환경에 노출되어 있던 대조구는 바람에 노출되어 있던처리구에 비해 수분흡수량이 가장 작은 것을 확인하였다. 하지만 풍속에 따른 식물의 생육을 조사한 결과 송악, 수호초 그리고 노랑조팝 모두 2m·s-1와 1m·s-1의 풍속을 처리했을 때 식물의 초장과 엽수의 증가에 가장 효과적이었다. 식물체의 수분흡수 양상을 수분흡수 기간 중의 평균기온 및 상대습도와의 관계를 비교해보면 평균기온 18.7℃로 가장 낮은 기온과 평균상대습도 62%로 가장 낮았던 5월 20일부터 26일까지의 모든 식물들의 수분흡수량이 낮은 경향을 나타내었다. 본 연구의 결과는 도심의 열섬화 현상을 경감시키기 위한 기초자료로 활용 가능할 것이며 바람이 많이 부는 도서지역의 녹지공간조성시에 풍속에 따른 식물생육과 활착 안정화에 효과적인 수종검토에 도움이 되고 공간이 협소한 도심지역 녹화에 효과적인 저면관수형 벽면녹화 수종선택에 큰 도움을 줄 수 있을 것으로 기대된다.

• 한국농공학회논문집
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• 제64권6호
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• pp.65-75
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• 2022

Livestock industry in Korea has been growing rapidly and has reached 23 trillion Korean won in 2021. This study focuses on broiler, which is one of the largest sectors in livestock industry. As the effects of climate change get more serious, primary industry such as livestock industry is fragile to climate change since it directly interacts with nature. Therefore, maintaining suitable rearing environment is important. One of the most frequently used ventilation type for controlling the rearing environment of broiler house, tunnel ventilation, causes frequent air velocity fluctuation which makes maintaining the rearing environment important. By measuring the air temperature, relative humidity and air velocity in various points inside the broiler house, the internal thermal environment uniformity was analyzed according to length, width and zone. The experimental house was found to have dead zone with high air temperature, relative humidity and low air velocity near the end of the inlet and at the end of the broiler house. By using heat stress index to analyze quantitatively, zone with highest heat stress index was found to increase by 7.55% compared to the lowest zone. As a result, to maintain uniform rearing environment inside the broiler house, different factors must be measured and analyzed and used to operate the environmental control facilities.

• 전기학회논문지
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• 제62권7호
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• pp.974-979
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• 2013

$TiO_2$ thin films are fabricated using R.F.sputtering method. $TiO_2$ thin films are coated on $Al_2O_3$ substrate printed IDE(interdigitated electrode). Impedance of thin films decreases according to increase relative humidity and it increases according to decrease measuring frequency. When substrate temperature is room temperature, impedance of thin films is from 45.68[MHz] to 37.76[MHz] within the limits from 30[%RH] to 75[%RH] at 1[kHz]. Whereas when substrate temperature is 100[$^{\circ}C$], impedance of thin films is from 692[kHz] to 539[kHz] within the limits from 30[%RH] to 75[%RH] at 1[kHz]. Impedance variation of thin films is bigger in low frequency regions than in high frequency regions. When substrate temperature is 100[$^{\circ}C$], impedance of thin films is lower than that of room temperature.