• Title/Summary/Keyword: Moisture condition

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Characteristic Analysis for Resistivity of Concrete (콘크리트의 저항률 특성 분석)

  • Kim, Sung-Sam;Choi, Jong-Kyu;Kim, Jae-Sung;Koh, Hee-Seog
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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    • 2006.05a
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    • pp.457-459
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    • 2006
  • In this paper was analyzed and compared the resistivity characteristic of concrete between moisture condition and dry condition to measure the variation of resistivity by water after making concrete scale block. The resistivity was decreased when the moisture of concrete block was gradually increased.

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Enhanced Stability of Acetyl-L-Carnitine Tablet under Accelerated Storage Condition

  • Kwon, Min-Chang;Wang, Hun-Sik;Shim, Ji-Yeon;Park, Jun-Sang
    • Proceedings of the PSK Conference
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    • 2003.10b
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    • pp.227.1-227.1
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    • 2003
  • Acetyl-L-carnitine (ALC), an endogenous component of L-Carnitine, is the acetyl ester of carnitine that has been reported to be beneficial in depressive disorders and Alzheimer's disease.ALC is so hygroscopic that deliquescence took place when it absorbed moisture by 15%(w/w) in a week and then reached steady-state at 45%(w/w) in 40$^{\circ}C$, 75% RH storage condition. Therefore it is necessary to prevent ALC from absorbing atmospheric moisture. For this purpose, we chose hydroxypropylmethylcellulose phthalate (HPMCP) an enteric polymer, as a film former. (omitted)

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Suggestion of Method to Classify Moisture or Dryness Condition from Moisture Index Obtained by NDVI (NDVI를 이용한 습윤지표를 기준으로 습윤 및 건조상황의 분류 방법 제안)

  • Kim, Joo-Cheol;Shin, Sha-Chul;Lee, Sang-Jin;Hwang, Man-Ha
    • Journal of the Korean Association of Geographic Information Studies
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    • v.12 no.4
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    • pp.84-94
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    • 2009
  • Moisture Index time series derived from NOAA/AVHRR data have showed to be useful for humid and arid states. The humid/arid states of the Geum river basin are classified by means of the moisture index estimated from the climatic water budget model. Validations showed that the moisture index has excellent ability to detect humid/arid conditions and to measure time of its onset, intensity and duration. In this study, a simple method to classify the moisture index is proposed by statistical distribution condition. Also, the moisture index is compared with the regional actual state to detect drought area.

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Combustion Characteristics of High Moisture Indonesia Coal as a Pulverized Fuel at Thermal Power Plant (미분탄 화력발전소 연료로서 고수분 인도네시아탄의 연소특성)

  • Kim, Jae-Kwan;Lee, Hyun-Dong
    • Journal of the Korean Society of Combustion
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    • v.14 no.3
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    • pp.16-23
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    • 2009
  • It is strongly desired for coal-fired power plants to utilize not only low-rank coals with high moisture contents, but also lowering cost with diversifying fuel sources. In this study, combustion characteristics of low rank coal with high moisture, and standard pulverized coals are experimentally investigated using TGA (Thermogravimetric Analysis) and DTF (drop tube furnace). The coals tested are three kinds of coal with moisture content ranging from 8.32 to 26.82%. The results show that under the air combustion condition, the burn-out time at TGA rises as moisture content increases, and standard pulverized coal with 8.32% moisture content showed the lowest activation energy of 55.73 kJ/mol. In case of the high amount of moisture, the combustion efficiency decreases due to evaporation heat loss, and unburned carbon in ash produced at combustion process in DTF increased. Aslo, initial deformation temperature of slag attached in alumina tube of DTF decreased with lowering the crytallinity of anorthite and augite. To improve the combustion reactivity and efficiency, it is effective to upgrade through drying the high moisture coal to moisture level (less than 10%) of standard pulverized coal.

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Exploration of Feedback Structures Between Surface Moisture and Aeolian Processes with a Modified Sand Slab Model (수정 모래판 모형을 이용한 지표수분 함량과 비사이동의 되먹임 구조 탐색)

  • Rhew, Hosahng
    • Journal of The Geomorphological Association of Korea
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    • v.24 no.3
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    • pp.61-81
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    • 2017
  • Traditional approaches to surface moisture problems in the context of aeolian research have focused on the initiation of sand movement, developing various models for predicting threshold velocity on a wet surface. They have been unsatisfactory, however, in explaining field observations because they have not incorporated spatiotemporal variability of surface moisture, the interactions between transported sand grains and surface, and the role of aeolian transport in controlling surface moisture. As Nield (2011) showed, a simplified numerical model can be used to investigate this issue. This research aims to explore the feedback structures between aeolian transport and surface moisture using a modified sand slab model. Key modifications are the introduction of simultaneous updating scheme for all the slabs and moisture-assigning procedures with and without aeolian transport. The major findings are as follows. Moist surface conditions suppress sand slab movement, leading to the development of smaller-scale topography. Available sands for aeolian transport are determined by the vertical patterns of moisture content with its variations from groundwater to the surface. Sand patches on a wet surface act as a localized source area. Sand movement drives immediate changes in surface moisture rather than time-lag reponses, mostly when moist conditions are dominant.

Changes of Soil Temperature and Moisture under the Agrivoltaic Systems in Fallow Paddy Field during Spring Season (봄철 영농형 태양광 시설 하부 휴경논 토양의 온도와 수분 변화)

  • Yuna Cho;Euni Cho;Jae-Hyeok Jeong;Hoejeong Jeong;Woon-Ha Hwang;Jaeil Cho
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.25 no.3
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    • pp.218-225
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    • 2023
  • An agrivoltaic system (AVS) is a combined system that generates power through photovoltaic panels (PVPs) installed above a field where a crop is cultivated. Although soil moisture is an important limiting factor for open-field crop production, particularly during spring season in Korea, it is not well considered in the utilization of AVS. Indeed, the application of water-energy-food nexus on the AVS should be necessary. In this study, the changes of soil moisture and temperature under the AVS was investigated in fallow paddy field during spring season. The AVS that has partial shading condition by PV panels was decreased soil temperature and increased soil moisture compared to open-field. Furthermore, the maximum of the change in soil moisture to the change in soil temperature had a negative correlation both on open-field and AVS under wet condition. It represents that the micro-climate under the AVS is in energy-limited condition. The open-field of relatively high soil temperature was in water-limited condition. The different behavior of soil moisture on the AVS should be considered for the sustainable agricultural system as related to water-energy-food nexus.

Assessment of Agricultural Drought Using Satellite-based TRMM/GPM Precipitation Images: At the Province of Chungcheongbuk-do (인공위성 기반 TRMM/GPM 강우 이미지를 이용한 농업 가뭄 평가: 충청북도 지역을 중심으로)

  • Lee, Taehwa;Kim, Sangwoo;Jung, Younghun;Shin, Yongchul
    • Journal of The Korean Society of Agricultural Engineers
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    • v.60 no.4
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    • pp.73-82
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    • 2018
  • In this study, we assessed meteorological and agricultural drought based on the SPI(Standardized Precipitation Index), SMP(Soil Moisture Percentile), and SMDI(Soil Moisture Deficit Index) indices using satellite-based TRMM(Tropical Rainfall Measuring Mission)/GPM(Global Precipitation Measurement) images at the province of Chungcheongbuk-do. The long-term(2000-2015) TRMM/GPM precipitation data were used to estimate the SPI values. Then, we estimated the spatially-/temporally-distributed soil moisture values based on the near-surface soil moisture data assimilation scheme using the TRMM/GPM and MODIS(MODerate resolution Imaging Spectroradiometer) images. Overall, the SPI value was significantly affected by the precipitation at the study region, while both the precipitation and land surface condition have influences on the SMP and SMDI values. But the SMP index showed the relatively extreme wet/dry conditions compared to SPI and SMDI, because SMP only calculates the percentage of current wetness condition without considering the impacts of past wetness condition. Considering that different drought indices have their own advantages and disadvantages, the SMDI index could be useful for evaluating agricultural drought and establishing efficient water management plans.

Moisturizing and Dryness Reduction Effect of Face Cream Containing Persicaria Perfoliata (L.) Extract (며느리배꼽추출물을 함유하는 페이스 크림의 보습 및 건조함 감소 효과)

  • Kim, Seong-Yun;Yoon, Hyun-Seo;Hyun, Sook-Kyung;Park, Chung-Mu
    • Journal of The Korean Society of Integrative Medicine
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    • v.10 no.3
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    • pp.27-36
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    • 2022
  • Purpose : This study was aimed to analyze the effects of cosmetics containing Persicaria perfoliata water extract (PPWE) on the skin moisturizing and improvement of skin condition in clinical trials. Methods : Clinical trial was conducted for five weeks after IRB approval at Dong-Eui University. Out of a total of 64 people, 15 people each were assigned to four groups as follows; control group A, B, C and the experimental group A that using cosmetic containing PPWE. Skin condition was measured two times, before and after clinical trial, by a professional skin analyzer, SDM (skin diagnosis system). Moisture and oil value of participants was analyzed twice, each morning and evening, using a portable device on their cheeks. In addition, the survey was investigated subjective satisfaction on change in skin condition and the satisfaction on the use of cosmetics. Result : The experimental group exhibited subjectively significant changes before and after clinical trials on skin its dryness (p=.039), blush (p=.017), and redness (p<.001). In addition, subjective evaluation was also the highest satisfaction in aspects of number of application (p=.003), amount of application (p=.002), moisture maintenance, and skin scratching frequency. The satisfaction on the use of cosmetics was the highest in the intention to repurchase (p=.045), recommendation willingness to others (p=.020), and intention to use various products (p=.001). Skin moisture of the clinical trial participants using the SDM, moisture level and elasticity of the experimental group increased by 12.94 and 10.28. Moisture level, which was measured by a portable device, was the most potently increased in the experimental group. Conclusion : Consequently, PPWE containg cosmetics exhibited the effects of moisturization and attenuated skin dryness in clinical trials, which might be utilized as a fundamental data to develop numerous lines of cosmetics.

Effects of Relative Humidity and Fiber Properties on the Moisture Permeability of Multilayer Fabric Systems (환경 및 섬유 특성이 멀티레이어 직물시스템의 투습성에 미치는 영향)

  • Suhyun Lee;Sohyun Park
    • Fashion & Textile Research Journal
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    • v.25 no.1
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    • pp.119-126
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    • 2023
  • This study aimed to determine the effects of relative humidity and fiber properties on the moisture permeability of multilayer systems by measuring water vapor transmission in the overlapping condition of various fabrics. The results confirmed that the property of the fabric in contact with the humid environment affects the moisture permeability. If the layer facing the humid environment is hydrophobic and the layer facing the dry environment is superhydrophobic, water vapor transmission increases by up to 17.8% compared to the opposite conditions. Comparing the correction values of the water vapor transmission reflecting the thickness of the specimen under the multilayer condition showed that permeability was higher when the hydrophilic or hydrophobic layer was facing the humid environment. The opposite was true from the "push-pull" effect of absorption mechanism. In the case of moisture permeability, the more hydrophilic the surface facing the humid environment, the more permeable that water vapor diffuses and passes through. It was concluded that the "pull-push" effect, in which water vapor diffuses widely through the hydrophilic facing a humid environment and then passes through the hydrophobic layer, contributes to the improvement of permeability. Permeability differed according to the multilayer overlapping condition. When the relative humidity was high, the "pull-push" effect was insignificant. This is caused by water droplets absorption after the partial migration of water due to condensation. These results suggest that the overlapping conditions and properties of fabrics should vary depending on heavy sweating or not.

Liquid Moisture Management and Surface Properties of the Fabric in Transient Condition (작업복 소재 직물의 액상 수분 전달 특성 및 표면특성 연구)

  • 유신정
    • Journal of the Korean Society of Clothing and Textiles
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    • v.25 no.1
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    • pp.61-70
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    • 2001
  • As important factors determining human sensorial comfort, liquid moisture management and surface properties of heat resistant workwear materials were examined. To figure out liquid moisture management properties of the test materials, absorption capacity, rate of absorption, and evaporation properties were assessed. A modified GATS(Gravimetric Absorbency Testing System) was used to measure the liquid moisture accumulation associated with the wicking of liquid moisture from sweating skin. The GATS procedure measures demand wettability of materials to take up liquid in a direction perpendicular to the fabric surface and it was modified to incorporate a special test cell and cover to assess absorption behavior in the presence of evaporation. Fabric stiffness, smoothness, number and the length of surface fibers, and an estimate of the contact area between the skin and fabric surface were measured to characterize the mechanical and surface properties of the test materials. Also an estimate of the force with which a fabric clings to moist skin was made using as wet-cling index.

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