• Title/Summary/Keyword: specific humidity

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Evaluation of SWAT Model for Hydrological Analysis of Hwa-Cheon Watershed (화천 지역의 수문분석을 위한 SWAT 모형의 적용성 평가)

  • Kim, Gi-Cheol;Kim, Jong-Geon;Park, Yun-Sik;Heo, Seong-Gu;Yu, Dong-Seon;Kim, Gi-Seong;Choe, Jung-Dae;Im, Gyeong-Jae
    • KCID journal
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    • v.14 no.2
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    • pp.207-213
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    • 2007
  • For sustainable development at a watershed, environment friendly site-specific management practices need to be developed and implemented. The soil and Water Assessment Tool(SWAT)model has been world-wide used to estimate stream flow, sediment, and nonpoint source pollutant loads, and effects on water quality of different management practices. In this study, the SWAT model was used to estimate the flow resources at Hwacheon areas using Digital Elevation Model(DEM),Land use, precipitation ,wind ,maximum and minimum temperature, solar radiation, humidity of watershed The R2 value and EI value for the comparison of SWAT estimated flow and measured flow were 0.87 and 0.67 respectively for calibration period, and the R2 value and E1 value for validation were 0.75 and 0.67 respectively. The comparison results show what the SWAT model is applicable to simulate hydrology behaviors at this study watershed.

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Analysis of Measurement Error for PM-10 Mass Concentration by Inter-Comparison Study (비교 측정을 통한 PM-10 질량농도의 오차 분석)

  • Jung, Chang-Hoon;Cho, Yang-Sung;Hwang, S.M.;Jung, Y.G.;Ryu, J.C.;Shin, D.S.
    • Journal of Korean Society for Atmospheric Environment
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    • v.23 no.6
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    • pp.689-698
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    • 2007
  • Particular attention is paid to the validity of PM-10 measurement using beta attenuation method. In this study, the inter-comparison studies were undertaken for PM-10 sampler with different measuring methods. The three beta attenuation monitoring instruments (BAM1020, FH C-14, and DIGS-150) and filter based gravitational method using High Volume Air Sampler were collocated and mass concentrations were compared from August to November, 2006. The results of the investigation show that beta attenuation monitoring instruments are comparable with gravitational method within 10% of measurement error. For specific conditions under high humidity and high concentrations, the inter-comparison results also showed a relatively good agreement and this can be explained as the effect of inlet heating of beta attenuation instrument. Subsequently, this study shows that beta attenuation monitoring instruments can be equivalently used with reasonable validity when compared gravimetric method.

Evaluation and Identification of Promising Bivoltine Breeds in the Silkworm Bombyx mori L.

  • Begum, Azeezur Rehman Naseema;Basavaraja, Hadikere Kallappa;Joge, Punjab Govindrai;Palit, Aditya Kumar
    • International Journal of Industrial Entomology and Biomaterials
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    • v.16 no.1
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    • pp.15-20
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    • 2008
  • Under the all India programme of evaluation of mulberry and silkworm genotypes, twelve bivoltine silkworm breeds obtained from Central Silkworm Germplasm Resource Centre, Hosur (CSGRC) were evaluated at the bivoltine silkworm breeding laboratory, Central Sericultural Research & Training Institute, Mysore (CSR&TI). These breeds were tested during September-October 2003, August-September 2004 and February-March 2005. The average temperature and humidity during September-October 2003 was $26.5^{\circ}C$ and 72.6% RH, while during August-September 2004, it was $26.5^{\circ}C$ and 75.2% RH and during February-March 2005 it was $24^{\circ}C$ and 48% RH respectively. The performance of the breeds in respect of 21 traits was studied and statistically analyzed using analysis of variance (Singh and Choudhary, 1985). Silkworm breeds were short-listed using multiple trait evaluation index method as suggested by Mano et at., (1993). Evaluation Index values were calculated for all the 11 traits of economic importance and six breeds were short-listed based on average index value 50 and above 50. Two breed viz., BV 183 (SMGS-1) have recorded average E.I. >50 in 10 traits (except in neatness) and ranked first and the breed BV 262 (SMGS9) with E.I. value >50 in nine traits except in cocoon weight and neatness ranked second, in the order of merit. These two breeds may be selected as resource material for evolving region specific silkworm breeds.

Studies on Absorption and Desorption Wood - Difference of Absorption and Desorption Behavior of Wood - (목재의 흡방습에 관한 연구 - 수종에 의한 흡방습성의 차이 -)

  • Lee, Weon-Hee
    • Journal of the Korean Wood Science and Technology
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    • v.19 no.4
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    • pp.52-61
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    • 1991
  • In this paper, the difference of the property of absorption and desorption for five species in semi-steady state are studied. The species used are listed in Table 1 and the dimension of specimen was $8\times8{\times}T$(Tangential direction)cm and tested in various conditions. A change of average moisture content with time were measured in each cycles. The results obtained are summarized as follows. When the relative humidity in air was maximum or minimum, the distribution of moisture In wood of all specimens were illustrated by exponential curves of decrease or increased from lace 10 center of wood. From the consideration of coefficient of decrease(C), the amount of moisture change of spruce was larger than the others. The pheonomenon was considered no relation to the specific gravity in air dry, but the wood structures. The velocity of the absorption and desorption for species decreased in the order spruce(Picea sitchensis) neodobam(Fagus crenata), solsong(Tsuga heterophylla), meranti(Shorea sp.) and kaesoo(Cercidiphyllum japoicum). In case of constant temperature and water vapor pressure is changed. the amount of absorbed moisture was larger than that of constant water vapor pressure and temperature vaned. In this fact, it is considered that the property of sorption of wood is strongly influenced by vapor pressure gradient than temperature gradient.

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Effect of Ball-milling on Hydrogen-reduction Behavior of WO3-CuO (WO3-CuO의 수소환원거동에 미치는 볼 밀링의 영향)

  • Kim, Dae-Gun;Shim, Woo-Seok;Kim, Young-Do
    • Korean Journal of Materials Research
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    • v.13 no.9
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    • pp.631-634
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    • 2003
  • To fabricate W-Cu nanocomposite powder, $WO_3$-CuO powder mixture was high-energetically ball-milled and subsequently hydrogen-reduced. The effect of ball-milling on the hydrogen-reduction behavior of$ WO_3$-CuO was investigated with non-isothermal hygrometric analysis during hydrogen-reduction. Increasing the ball-milling time, the reduction peak temperatures of humidity curves were shifted to low temperature. It was considered that the reduction temperature should be decreased because the specific surface area of each oxide considerably increased with increasing the ball-milling time. In case of ball-milling for 0 h, $WO_3$and CuO were independently hydrogen-reduced and W particles were nucleated on the surface of Cu adjacent to W by CVT. However, in case of ball-milling for 50 h, the aggregates of about 200-300 nm were observed. W particles of size below 30-50 nm were homogeneously distributed with Cu in the aggregates.

A Study on Estimation of Cooling Load for Effective Control of Ice Thermal Storage System (빙축열 시스템의 효율적인 제어를 위한 냉방부하 예측에 관한 연구)

  • Yoo, Seong-Yeon;Han, Kyu-Hyun;Lee, Je-Myo;Han, Seung-Ho
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.20 no.2
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    • pp.128-136
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    • 2008
  • It is necessary to estimate the cooling load of the next day for effective control of ice thermal storage system. In this paper, new methodology is proposed to estimate the cooling load using design parameters of building and predicted weather data. Only six input parameters such as sensible heat coefficient and constant, latent heat coefficient and constant, maximum and minimum temperature are necessary to obtain hourly distribution of cooling load for the next day. Two benchmarking buildings(hospital and research institute) are selected to validate the performance of the proposed method, and the estimated cooling loads in hourly and daily bases are calculated and compared with the measured data for E hospital. The estimated results show fairly good agreement with the measured data for both buildings.

A Study on Estimation of Cooling Load Using Forecasted Weather Data (집단 건물 면적을 이용한 시간별 냉방부하 파라미터 설정 및 예측에 관한 연구)

  • Han, Kyu-Hyun;Yoo, Seong-Yeon;Lee, Je-Myo;Song, Yang-Sup
    • Proceedings of the SAREK Conference
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    • 2008.11a
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    • pp.440-445
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    • 2008
  • In this paper, new methodology is proposed to estimate the cooling load using areas of building group and predicted weather data. Only three parameters such as maximum, minimum temperature and building area are necessary to obtain hourly distribution of cooling load for the next day. The maximum and minimum temperature that are used for input parameters can be obtained from forecasted weather data. The areas of building group are used for setting several parameters that are used for estimate cooling loads. Benchmarking building(research building) is selected to validate the performance of the proposed method, and the estimated cooling loads in hourly bases are calculated and compared with the measured data for benchmarking building. The estimated results show fairly good agreement with the measured data for benchmarking building.

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Analysis on the Drying Performance with the Flow Rate of Circulation Air in a Heat Pump Dryer (순환 공기 유량의 변화를 고려한 열펌프 건조기의 성능 해석)

  • Lee, Kong-Hoon;Kim, Oak-Joong;Lee, Sang-Ryoul
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.21 no.1
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    • pp.1-8
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    • 2009
  • The simulation of a heat pump dryer has been carried out to figure out the effect of air flow rate on the drying performance represented by MER, SMER, and so on. The simulation includes the analyses of one-stage heat pump cycle and simple drying process using the drying efficiency. The heat pump cycle with Refrigerant 134a has been considered. In the dryer, some of drying air from the drying chamber flows through the heat pump system, the rest of air bypasses the heat pump system. The two air flows joins before the drying chamber inlet. The performance parameters considered in the present study are MER, SMER, the temperature and humidity of drying air. Those parameters are compared for different total air flow rate or bypass air flow rate.

Graphene nanosheets encapsulated poorly soluble drugs with an enhanced dissolution rate

  • Shen, Shou-Cang;Ng, Wai Kiong;Letchmanan, Kumaran;Lim, Ron Tau Yee;Tan, Reginald Beng Hee
    • Carbon letters
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    • v.27
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    • pp.18-25
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    • 2018
  • In this study, graphene oxide(GO) was used as drug carriers to amorphize poorly watersoluble drugs via a co-spray drying process. Two poorly water-soluble drugs, fenofibrate and ibuprofen, were investigated. It was found that the drug molecules could be in the graphene nanosheets in amorphous or nano crystalline forms and thus have a significantly enhanced dissolution rate compared with the counterpart crystalline form. In addition, the dissolution of the amorphous drug enwrapped with the graphene oxide was higher than that of the amorphous drug in activated carbon (AC) even though the AC possessed a larger specific surface area than that of the graphene oxide. The amorphous formulations also remained stable under accelerated storage conditions ($40^{\circ}C$ and 75% relative humidity) for a study period of 14 months. Therefore, graphene oxide could be a potential drug carrier and amorphization agent for poorly water-soluble drugs to enhance their bioavailability.

Changes in Physical and Mechanical Properties of Freon-Adsorbed and Heat - Treated Leaf Tobacco (Freon Gas흡착 및 열처리에 의한 담배조직의 물리적, 역학적 특성변화연구)

  • Kim, Ki-Hwan;Yoo, Kwang-Kun;Joo, Young-Serg
    • Journal of the Korean Society of Tobacco Science
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    • v.6 no.1
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    • pp.39-49
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    • 1984
  • In the tobacco industry, it is important to study the change of mechanical property occurring the expansion process. The purpose of this study is to attain basic data for development of a tobacco expansion method. 1 . Freon gas was adsorbed to tobacco under various conditions of temperature, relative humidity and pressure, and then the amount of freon gas adsorbed was analyzed by GC. Freon adsorption rate of Burley 21 was more than that of By104 at the same condition and about 17 $\pm$ 1% moisture content produced better adsorption rate. 2. Freon adsorbed sample were heated to about $150^{circ}C\;to\;230^{\circ}C$ in a drying oven and recycle duct form about 2 to 30 seconds, and then the change of mechanical property were measured. Heated leaf was damaged when the tissue was pressed by the force of above $0.5x10^8dyn/cm^2$. The optimum condition of no damage of the sample was below the temperature of 15$0^{\circ}C$ and heating time of 10 seconds. It was more economically advantages to treated sample in a recycle duct than to be in a drying oven. By this process, the specific volume of the heated sample was increased from 80 to 110 percent in comparison to that of untreated sample.

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