• 제목/요약/키워드: water-absorption

검색결과 3,269건 처리시간 0.031초

흡수식 냉온수기의 부분부하에 따른 냉각수 변유량시 성능특성에 관한 연구 (A Study on the Performance Characteristics of an Absorption Chiller for Variable Cooling Water Flow Rate at Partial Load Conditions)

  • 박찬우;조현철;강용태
    • 설비공학논문집
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    • 제16권1호
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    • pp.26-33
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    • 2004
  • In general, an absorption chiller or heat pump is operated under the constant cooling water flow rate condition even though the system works with a partial load. The objective of this paper is to study the effect of the cooling water flow rates and the temperature of cooling water on the system performance to find the energy saving methode for the partial load operation of the double effect $H_2O$/LiBr absorption chiller. It is found that the performance of the system is sensitive to the temperature of cooling water than the cooling water flow rate, so the decrease of the performance due to reducing the cooling water flow rate can be overcome with the reduction of the cooling water temperature by 1$^{\circ}C$. The flow rate of the cooling water flow rate ranges from 50% to 100% of the flow rate at normal conditions with a partial load. It is also found that the operation cost of the cooling water pump and the cooling tower can be reduced by 23%.

해수의 광학적 성질에 관한 연구 ( 1 ) - 부산근해의 하계 및 추계변화 (Optical Properties of Sea Water 1 Variation of the Coastal Sea Water Near Busan in Summer and Autumn)

  • 양용림
    • 수산해양기술연구
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    • 제11권1호
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    • pp.8-14
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    • 1975
  • The optical properties of the sea water were studied by use of underwater lux-meters in the coastal waters of Busan from May to November 1975. The absorption coefficient of the sea water in the area ranges from O. 169 to 1. 049 and the mean absorpflOn coefficient is 0.413. Maximum monthly mean absorption coefficient (0. 56) was observed in August, while the minimum was O. 338 in September. There was a distinct discontinuity layer of the absorption coefficient in accordance with the thermocline and the halocline in summer. The mean transparency of the area was 3. 8 meters, and transparency in autumn was higher than that in summer. The relation between absorption coefficient (m) and transparency (D) was deduced, m=1. 57/ D. The rate of light penetration at 5 m-layer of sea water was 2. 5 percent when the solar altitude was six degree in July 1975.

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Contact Method에 있어서 Masking Data에 관한 연구 (A Study on the Masking Data in Contact Method for Transparent Copy)

  • 곽선엽
    • 한국인쇄학회지
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    • 제6권1호
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    • pp.67-74
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    • 1988
  • Absorption rates of oxygen in water soluble inks on the printing rollers were measured. As a results of experiments, could be obtained the data of rates of absorption of oxygen in 4 kinds of water soluble inks, and found the difference of absorption rate of oxygen on the parallel plates and rotating rolles.

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실 단면 형상과 니트 구조 인자가 흡한속건 소재의 수분이동 특성에 미치는 영향 (Effect of Yarns Cross-Sections and Structure Parameters of Its Knitted Fabrics to Moisture Transport of Perspiration Absorption and Fast Dry Fabrics)

  • 김현아
    • 한국의류산업학회지
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    • 제20권4호
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    • pp.457-463
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    • 2018
  • This study examined the water absorption and drying properties of the thirteen types of the knitted fabrics for sports wear. These physical properties were analysed with relation to the constituent fiber cross-sectional shape and structure parameters of the knitted fabrics by regression analysis. Absorption and drying properties of the knitted fabric specimens were increased with increasing the porosity of the constituent yarns, which was attributed to the capillary channels in the yarns. The water absorption and drying properties were increased and decreased with increasing tightness factor and stitch density of the knitted fabric. The absorption property of the knitted fabric for perspiration absorption and fast dry sport-wear clothing was mostly influenced mostly by fiber cross-sectional shape and its characteristics, whereas, drying property was dependent on the structural parameters of the knitted fabric such as tightness factor and stitch density. Therefore, superior perspiration absorption and fast drying knitted fabric could be obtained in the fabric structure with optimum tightness factor and stitch density, and constituent yarn structure with non-circular fiber crosssection and high porosity. GATS method and MMT method are used to measure sweating fast drying properties and it is necessary to carry out studies using these measurement methods in order to compare with the results of this study.

Fick's second law 를 이용한 수냉식 발전기 고정자 권선의 건전성 예지 (Health prognostics of stator Windings in Water-Cooled Generator using Fick's second law)

  • 윤병동;장범찬;김희수;배용채
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2014년도 추계학술대회 논문집
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    • pp.533-538
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    • 2014
  • Power generator is one of the most important component of electricity generation system to convert mechanical energy to electrical energy. I t designed robustly to maintain high system reliability during operation time. But unexpected failure of the power generator could happen and it cause huge amount of economic and social loss. To keep it from unexpected failure, health prognostics should be carried out In this research, We developed a health prognostic method of stator windings in power generator with statistical data analysis and degradation modeling against water absorption. We divided whole 42 windings into two groups, absorption suspected group and normal group. We built a degradation model of absorption suspected winding using Fick's second law to predict upcoming absorption data. Through the analysis of data of normal group, we could figure out the distribution of data of normal windings. After that, we can properly predict absorption data of normal windings. With data prediction of two groups, we derived upcoming Directional Mahalanobis Distance (DMD) of absorption suspected winding and time vs DMD curve. Finally we drew the probability distribution of Remaining Useful Life of absorption suspected windings.

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굳지않은 콘크리트의 단위수량 추정에 미치는 골재요인의 영향 (Influence of Aggregate Factor on the Estimation of Water Content in Fresh Concrete)

  • 김영득;황인성;전충근;한천구;김광서
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2002년도 가을 학술발표회 논문집
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    • pp.223-226
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    • 2002
  • This study is performed to investigate the influence of aggregate factor on the estimation of water content in fresh concrete. According to the results, water content is estimated higher in the case of basalt and granite aggregate than in the case of limestone because absorption water ratio of basalt and granite is large. As the replacement ratio of recycled aggregate increases, water content is estimated higher. But, after correcting absorption water ratio of aggregate, estimated water content is similar to mixture water content. Therefore, it is important to know the absorption water ratio of aggregates accurately, to estimate water content.

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다시마와 미역의 섭취가 발암물질에 의한 DNA 손상과 칼슘 및 철 흡수에 미치는 영향 (Effect of Seatangle and Seamustard Intakes on Carcinogen Induced DNA Adduct Formation and the Absorption of Calcium and Iron)

  • 성미경
    • Journal of Nutrition and Health
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    • 제33권7호
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    • pp.717-724
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    • 2000
  • A number of epidemiological studies has indicated lifestyles including dietary habits are closely related to the development of certain forms of cancer. These findings have led several investigators to identify the ways in which these factors mdulate the risk of cancer. Seaweeds are rich sources of non-digestible polysaccharides which possibly posses physiological functions. In vitro studies showed several components in seaweeds inhibit tumor cell growth and mutagenicity of known food mutagens. On the other hand non-digestible polysaccharides of different food sources negatively affect mineral nutrition by decreasing mineral absorption. The objectives of this study was to investigate the effect of major seaweed intake on azoxymethane(AOM) - induced DNA damage a known cancer initiation step and on apparent absorption of calcium and iron. To accomplish these objectives twenty five ICR mice were divided into five groups and fed one of the following diets for 10 days : control diet d, diet containing 10% water-soluble fraction of seamustard or seatangle diet containing 10% water-insoluble fraction of seamustard or seatangle. AOM was injected 6 hours before sacrifice and N7-methylated guanines from the colonic DNA were quantified using a gas chromatography -mass spectroscopy. Fecal samples were collected on days 4 and 8. Caclium and iron contents of the diets and feces were analyzed using an atomic absorption spectrophotometry to determine the apparent absorption of these minerals. Results are as follows. AOM-induced guanine methylation of colon was decreased in animals fed diets containing water-soluble fractions of seamustard or seatangle compared to those in animals fed control diet although only the seatnagle fed group showed statistically significant effect. Apparent calcium absorption was significantly reduced in animals fed diets containing water-insoluble fractions of seaweeds. Iron absorption was significantly decreased and negatively balanced in animals fed diets containing water-insoluble fractions of both seaweeds, and water-soluble fraction of seatangle. In conclusion, seamustard and seatangle intakes may effectively prevent colon tumorigenesis by reducing a carcinogen-induced DNA damages, and more mechanistic studies on possible role of seaweeds on carcinogenesis are required. Also, adverse effects of seaweed diets cintaming a large amount of polysaccharides on mineral nutrition should be carefully monitored.

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파우더 베이스 메이크업 제품의 지속성 평가 방법 연구 (A Study of Cosmetic Sustainability Evaluation of Powder Base Make-up Products)

  • 이상길;김기중;김영호;표형배;이동규
    • 대한화장품학회지
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    • 제41권3호
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    • pp.209-218
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    • 2015
  • 파우더 베이스 메이크업 제품은 피부에 도포되어 8 ~ 12시간 동안 부착되며 피부에서 분비되는 땀이나 피지 등의 분비물에 의해 화장막이 변화된다. 따라서 메이크업 화장의 지속성은 중요한 품질 요소 중 하나이며 평가도 중요하다. 본 연구는 파우더 제품에서 지속성 평가를 위해 여러 가지 방법으로 파우더 반제품의 흡수, 흡유, 발수, 발유 등의 특성을 측정해보고 객관적인 평가 방법과 비교하여 연관성을 확인하여 지속성 평가 시 중요한 파우더의 특성을 살펴보았다. 또한 평가조건(땀과 피지 분비량 차이, 기온 및 습도 등)에 크게 영향을 받지 않으면서 지속성을 예측할 수 있는 간단한 방법을 검토해보았다. 타정 흡유도와 모세관법 및 침지법 등으로 반제품의 흡수, 흡유, 발수, 발유 특성을 측정해본 후 색차계와 ROBO skin analyzer 데이터와 비교하였다. 그 결과 흡수, 발유 특성보다는 흡유와 발수 특성이 지속성과의 연관성이 크다는 것을 확인할 수 있었고 흡유, 발수 특성을 확인하는 것으로 빠르고 손쉽게 지속성에 대한 예측이 가능하리라 생각되었다. 그 중 흡유 특성은 타정 흡유도와 모세관법이, 발수 특성은 침지법이 지속성에 대한 상대평가 방법으로 유용할 것이라고 판단되었다.

Spectral Distribution and Spectral Absorption of Suspended particulates in Waters of Sanya Bay

  • Yang, Dingtian;Cao, Wenxi
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume I
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    • pp.495-498
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    • 2006
  • Optical profile and spectral absorption of suspended solids in waters of Sanya bay was measured on August 8-14, 2003. Optical profile was taken by using MicroPro optical profile. Apparent optical indexes, vertical diffuse attenuation coefficient ($K_d$) and water leaving radiance (Lw), were calculated. $K_d$ at the blue end of the spectrum was greater than that at the red end of the spectrum in waters near Sanya River mouth, however, in waters near open sea, $K_d$ at the blue end of the spectrum was smaller than that at the red end of the spectrum. Distribution of water leaving radiance was relatively higher in waters near Sanya River mouth, but relatively weaker in near open sea water. Spectral absorption of suspended particulates was also measured. Results showed that the spectral absorption of chlorophyll a was greater in waters near Sanya river mouth, but relatively weaker in waters near open sea, which indicated higher concentration of phytoplankton in waters near Sanya river mouth. Except for water at the 5th sampling station, the ratio of spectral absorption of chlorophyll a to total suspended particulates in surface waters was greater than that in bottom waters at all stations.

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수생식물을 이용한 수질정화에 관한 연구 (Aquatic Plants for Wastewater Treatment)

  • 나규환;권성환;이장훈
    • 한국환경보건학회지
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    • 제22권3호
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    • pp.49-55
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    • 1996
  • Water parsley(Oenanthe javanica(Blume) DC) was raised with varying population density(S) in the laboratory aquarium unit to determine the growth equation. The population density was measure after 7 days. The resultant growth curve was well fit to the equation 1/S = A+B (1/S0) with a high correlation coefficient ($R^2$ = 0.999). The maximum specific absorption rate was $9.011 \times 10^{-5}$ kg $NO_x-N/kg$ water parsley$\cdot$day and $1.31 \times 10^{-5}$ kg $PO_4-P/kg$ water parsley$\cdot$day when the average population density was $2.62 kg/m^2$. The relationship between population density and nutrient absorption rate, the absorption rate of $NO_x-N$ was 5.04~5.24 mg/l$\cdot$day when the population density was $7.51~10.0 $mg/m^2\cdot day$ and the absorption rate of $PO_4-P$ was 0.56~0.78 mg/l$\cdot$day when the population density was 5.02~10.0 $kg/m^2\cdot day$. Taking into account the nutrient absorption rate and growth rate, the population density between $7.0 kg/m^2\cdot day$ and $8.0 kg/m^2 \cdot day$ was selected. The removal rate of nutrient was investigated after 7 days culture. Removal rate of $NO_x-N$ was 95.6~99.95% with initial concentration of 35 mg $NO_x-N/l$, and the removal rate of $PO_4-P$ was also high, indicating 80.24~98.9% with initial concentration of 5.95 mg $PO_x-P/l$.

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