• 한국수소및신에너지학회논문집
• /
• 제34권4호
• /
• pp.327-333
• /
• 2023

The water gas shift reaction was carried out using the commercial catalyst pellet and the simulated gases expected to occur from waste plastic gasification. In the water gas shift reaction, the high temperature shift reaction and the low temperature shift reaction were continuously performed with CO:H₂O ratio of 1:2, 1:2.5, and 1:3, and the CO conversion and H₂ increase rate were evaluated. The H₂ increase rate increased in order to CO:H₂O ratio of 1:3 > CO:H₂O ratio of 1:2.5 > CO:H₂O ratio of 1:2. The CO conversion showed a high value of more than 97% at each CO:H₂O ratio. The water gas shift reaction at a CO:H₂O ratio of 1:3 showed the highest H2 increase rate and CO conversion.

• Journal of the Korean Statistical Society
• /
• 제13권2호
• /
• pp.73-80
• /
• 1984

In this paper, likelihood-ratio test has been derived for testing multisample sphericity in complex multivariate Gaussian populations. The $h^{th}$ moment of the test statistic is given and its exact distribution has been derived using inverse Mellin transform. Asymptotic distribution of the statistic is also given.

• 해양환경안전학회:학술대회논문집
• /
• 해양환경안전학회 2018년도 공동국제학술발표회
• /
• pp.190-190
• /
• 2018

• 한국환경생태학회지
• /
• 제28권1호
• /
• pp.80-89
• /
• 2014

본 연구는 학교의 옥외공간 중 학생들의 휴식 및 활동량이 가장 많고, 높은 열과 낮은 열을 가지는 운동장 및 녹지공간을 대상으로 열적 쾌적성 지표 중 UTCI, PMV, WBGT를 이용하여 학생들이 느끼는 열적 쾌적성을 비교 분석하고자 하였다. 연구대상지는 인천광역시 학교시설(3개교)을 대상으로 하였으며, 조사기간은 2013년 7 ~ 8월까지 실시하였다. 측정항목으로 열적 쾌적성 지표의 경우 UTCI, PMV, WBGT를, 녹지구조는 녹피율과 녹지용적계수를 측정하였다. 학교별 녹지용적계수는 A학교($4.71m^3/m^2$) > B학교($3.34m^3/m^2$) > C학교($0.38m^3/m^2$)의 순이었으며 학교별 열적 쾌적성 지표를 살펴보면, UTCI는 녹지공간 $32.30{\sim}35.68^{\circ}C$, 운동장 $40.66{\sim}2.94^{\circ}C$, PMV수치는 녹지공간 1.76~2.66이었으며 운동장은 모두 3으로 나타났다. WBGT는 녹지공간 $26.15{\sim}31.38^{\circ}C$, 운동장 $31.67{\sim}34.53^{\circ}C$이었다. 3개 지표 모두 녹지공간 대비 운동장에서 매우 불쾌적한 수준이었다. 열적 쾌적성 및 녹지와의 상관분석결과, 열적 쾌적성 지표인 UTCI, PMV, WBGT 모두 일사, 흑구온도와는 정의 상관관계를, 녹피율 및 녹지용적계수와는 부의 상관관계로 나타났다.

• 한국세라믹학회지
• /
• 제32권4호
• /
• pp.462-470
• /
• 1995

The characteristics of spray-dried granules are important for dry pressing operation since they have great influences on die-filling, compaction ratio, and resulting green microstructure. An attempt was made to control granule morphology and the packing structure of fine Si3N4 particles in granules by adjusting suspension property. Mercury porosimetry was used to characterize the pore structures of both granules and green compacts. Finally, the effects of particle packing structure in granules and green microstructure on sintering behavior were investigated.

• 한국농공학회지
• /
• 제42권4호
• /
• pp.59-66
• /
• 2000

This study was carried out to investigated the water requirement of twisted sweet peppers which are cultivated in a green house. The meteorological conditions during the experiment period was close to that of normal year except the temperature and relative humidity. The growth status was improved with the increased saturation ratio. The range of the variation of daily water requirement were very large. The peak consumption occurred in the early August. And the higher saturation ratio resulted in higher water requirement. The total water requirement were about 57.180g/d/plant for pot with 100% (P100) of saturation , about 38.700g/d/plant for pot with 80%(P80) of saturation , about 23,720g/d/plant for pot with 60%(P60) of saturation, and about 53, 390g/d/plant for field cultivation in the green house, respectively. The water requirement was correlated with average ambient temperature and growing status, while no significant correlation were found between water requirement and minimum relative humidity or intensity of solar radiation. And the higher correlation was shown as the saturation ratio was increased. The transpiration coefficients of twisted sweet pepper were 378.0g/g for field cultivation in the green house, 363.3g/g for P100, 338.7g for P80 which was the smallest among pot cultivation , and 472.1g/g for P60 , respectively.

• 한국환경과학회지
• /
• 제24권5호
• /
• pp.647-655
• /
• 2015

In this study, to targeting Songpa of Seoul, were analyzed the effect on the noise mitigation in roadside buffer green spaces. Noise of Songpa Street buffer green space was determined to be higher during the day than at night. In addition, it was most of 60 db or more. However, the noise reduction function of the buffer green was not greatly affected by time. In the case of noise reduction rate, during the day time it was the order of the mounding type (18.14%)> plain type (5.73%)> slope type (4.08%), And, in the case of night time, it was the order of the mounding type (11.29%)> slope type (10.22%)> plain type (4.42%). Noise reduction rate, all of the daytime, was the highest in the mounding type. As a result of the factors on the amount of reduction of noise, More physical structure is mounding type, green structure is the stratification of green space, and the number of individuals is large, the higher the tree planting density, it is determined that the noise reduction effect is high. Also, factors affecting the noise reduction effect of the day and night were different.

• Nutritional Sciences
• /
• 제8권3호
• /
• pp.175-180
• /
• 2005

Green tea, which has high polyphenols amount, is thought to have hypocholesterolemic effects. The present study was performed to further examine the hypocholesterolemic action of green tea, especially (-) epigallocatechin gallate (EGCG) for its effect on diet-induced hypercholesterolemia in rats. Male Sprague-Dawley rats (n=15) were fed a green tea-free diet (control), $1.0\%$ green tea catechin (catechin) or $0.5\%$ green tea catechin EGCG for seven weeks. Hypercholesterolemia was induced by adding $1\%$ cholesterol and $0.5\%$ cholic acid to all diets. There was no difference in food intake and body weight gain among the groups. The green tea EGCG treatment led to a significant improvement in plasma levels of total cholesterol, low density lipoprotein (LDL)-cholesterol and high density lipoprotein (HDL)/LDL ratio (p<0.05). There was no significant effect on the plasma HDL-cholesterol level. The catechin treatment led to a 4.19-fold increase in the LDL-receptor mRNA level compared to the control, but the EGCG treatment did not affect the hepatic LDL-receptor mRNA level. Our results suggest that when blood cholesterol level is down-regulated by green tea EGCG, the LDL receptor gene-independent pathway may dominate the hypocholesterolemic action of EGCG.

• 한국작물학회지
• /
• 제53권4호
• /
• pp.413-416
• /
• 2008

The cultivation of green manure crop is considered as a good management practice by increasing soil organic matter and fertility levels. This experiment was conducted to improve the soil environment under rice-based cropping system at paddy soil (fine loamy, mixed, nonacid, mesic, family of Aeric Fluventic Haplaquepts) in National Institute of Crop Science (NICS), Korea in 2006 to 2007. The variation of soil temperature in green manure plots was lower than without green manure (control) during spring season (April to May). The temperature variation of no tillage plot (broadcast before rice harvest) was the lowest among treatments. After green manure cropping, the soil bulk density and porosity ratio were improved at the top soil. The production of green manure was the highest athairy vetch and barley mixture plot by partial tillage. However, mixture treatment had no improvement on soil organic matter. After rice cropping with green manure application, soil quality was improved such as soil physical properties except mixture treatment. Therefore, we suggest that soil quality should be improved by green manure cultivation under rice-based cropping system.

• 한국자원식물학회지
• /
• 제9권3호
• /
• pp.279-284
• /
• 1996

청양재래와 유성 2호 2품종을 공시하여 원줄기를 10cm로 고정시키고, 구기순 채취길이를 20cm, 30cm, 40cm로 달리 하였을 때 구기자나무의 생육적 특성 및 구기순의 수량을 알아봄으로써 구기순 재배에 필요한 기초 자료를 얻고자 수행한 시험 결과를 요약하면 다음과 같다. 1. 유성2호가 청양재래에 비해 구기순 수, 구기순당 엽수, 주당 총엽수, 수확횟수는 많았고 구기순의 굵기는 굵었으나 엽장, 엽폭은 작았다. 2. 청양재래의 구기순 채취횟수는 4.5회이었으나 유성2호는 5.5회로서 청양재래보다 1회 더 채취할 수 있었다. 3. 구기순의 건물중은 $1.01{\sim}1.03g$이었고, 줄기 : 엽비율은 46 : 54로 엽비율이 8% 높았다. 4. 구기순의 수량은 청양재래가 $108{\sim}204kg/10a$이고 유성 2호는 $215{\sim}383kg/10a$ 이었으며, 유성 2호는 년차간의 수량 증감폭이 적어 재식 당년의 수량을 기대할 수 있었다. 5. 청양재래의 구기순 수를 제외한 공시품종의 각 생육형질은 수량과 고도의 정(正)의 상관적이었으며, 유성 2호의 구기순 수는 주당 총엽수를 제외한 각 생육형질 및 수량과 부(負)의 상관이 있었다.