• Title/Summary/Keyword: surface moisture

Search Result 1,411, Processing Time 0.029 seconds

Monitoring of Chemical Changes in Explosively Puffed Ginsengvand the Optimization of Puffing Conditions

  • Yoon, Sung-Ran;Lee, Gee-Dong;Kim, Hyun-Ku;Kwon, Joong-Ho
    • Journal of Ginseng Research
    • /
    • v.34 no.1
    • /
    • pp.59-67
    • /
    • 2010
  • Response surface methodology was used to predict the optimum conditions of explosive puffing process for ginseng. A central composite design was used to monitor the effect of moisture content and puffing pressure on dependent variables such as functional compounds (extract yield, crude saponin, acidic polysaccharide, and total phenolic content) and sensory properties. Correlation coefficients $(R^2)$ of models for crude saponin, acidic polysaccharide, and total phenolic content were 0.9176 (p<0.05), 0.9494 (p<0.05), and 0.9878 (p<0.001), respectively. Functional compounds increased with decreasing moisture content and increasing puffing pressure. Overall palatability was high at 15-20% moisture content and 98-294 kPa of puffing pressure. On the basis of superimposed contour maps for functional compounds and overall palatability of puffed ginseng, the optimum ranges of puffing conditions were 10-17% moisture content and 294-392 kPa puffing pressure.

An experimental study on the durability evaluation of concrete applied functional nano composite inorganic activated carbon based coatings (기능성 나노복합 무기질 활성탄계 표면 처리제를 적용한 콘크리트의 내구성능 평가에 관한 실험적 연구)

  • Yang, Gi-Young;Jang, Seog-Jae;Baek, Jong-Myeong
    • Proceedings of the KSR Conference
    • /
    • 2006.11b
    • /
    • pp.1385-1390
    • /
    • 2006
  • Concrete structure can be deteriorated by ingress of moisture and aggressive agents. To maintain the sound performance of concrete structure during the service life, it needs to protect concrete from ingress of moisture and aggressive agents before arising deterioration of concrete. Protection of concrete is possible by surface treatment. In this study, durability of the functional nano composite inorganic activated carbon based coatings which can provide a barrier against the ingress of moisture or aggressive ions to concrete is discussed. For the durability evaluation of the coatings, fine void structure evaluation test, chloride penetration acceleration test, accelerated carbonation test, freezing and thawing test, and the accelerated test of chemical erosion are conducted. As the result of this study, the functional nano composite inorganic activated carbon based coatings which became one formed complex compound with adsorption and porosity on concrete surface, had an effect on the function of far infrared radiation, antimicrobial action, air cleaning, airing assurance, and the interception of moisture of deterioration factor, chloride ion, carbon dioxide, sulfate, and so on.

  • PDF

Moisture distribution in concrete subjected to rain induced wetting-drying

  • Sarkar, Kaustav;Bhattacharjee, Bishwajit
    • Computers and Concrete
    • /
    • v.14 no.6
    • /
    • pp.635-656
    • /
    • 2014
  • A rational estimation of moisture distribution in structural concrete is vital for predicting the possible extent and rate of progression of impending degradation processes. The paper proposes a numerical scheme for analysing the evolution of moisture distribution in concrete subjected to wetting-drying exposure caused by intermittent periods of rainfall. The proposed paradigm is based on the stage wise implementation of non-linear finite element (FE) analysis, with each stage representing a distinct phase of a typical wet-dry cycle. The associated boundary conditions have been constituted to realize the influence of various meteorological elements such as rain, wind, relative humidity and temperature on the exposed concrete surface. The reliability of the developed scheme has been demonstrated through its application for the simulation of experimentally recorded moisture profiles reported in published literature. A sensitivity analysis has also been carried out to study the influence of critical material properties on simulated results. The proposed scheme is vital to the service life modelling of concrete structures in tropical climates which largely remain exposed to the action of alternating rains.

A Perspective on Radar Remote Sensing of Soil Moisture

  • Park, Sang-Eun
    • Korean Journal of Remote Sensing
    • /
    • v.27 no.6
    • /
    • pp.761-771
    • /
    • 2011
  • The sensitivity of microwave scattering to the dielectric properties and the geometric structure of soil surfaces makes radar remote sensing a challenge for a wide range of environmental issues directly related to the condition of natural surfaces. Especially, the potential for retrieving soil moisture with a high spatial and/or temporal resolution represents a significant contribution to hydrological and ecological modeling. This paper aims to review the current state of the art in SAR technology and methodological issues towards the discovery of a new potential accurate monitoring of soil moisture changes. In this paper, important parameters or constraints significantly affect the sensitivity of the measurements to soil moisture, such as roughness statistics, spatial resolution, and local topography, are discussed to improve the applicability of SAR remote sensing techniques. This study particularly intends to discuss important notes for developing smart and reliable methods capable of retrieving geophysical information.

Land Surface Soil Moisture Effect on DInSAR

  • Lee C.W.;Kim S.W.;Won J.S.
    • Proceedings of the KSRS Conference
    • /
    • 2004.10a
    • /
    • pp.174-177
    • /
    • 2004
  • Differential interferometric phases from JERS-1 L­band data sets show spatial variation of path-length ranging from a few mm to several cm. The variation may be caused by changes in soil moisture contents, i.e. variation of penetration depth and the swelling of soils. Although the amount of total effect caused by soil moisture is not measurable, it is clear that the soil moisture according to precipitation is another factor to be considered in DInSAR analysis. We also discuss DInSAR characteristics in a rice paddy according to irrigation conditions, and discrimination of hydrological features such as stream channels and watershed boundaries by applying DInSAR technique.

  • PDF

Retrieval of surface parameters in tidal flats using radar backscattering model and multi-frequency SAR data

  • Choe, Byung-Hun;Kim, Duk-Jin
    • Korean Journal of Remote Sensing
    • /
    • v.27 no.3
    • /
    • pp.225-234
    • /
    • 2011
  • This study proposes an inversion algorithm to extract the surface parameters, such as surface roughness and soil moisture contents, using multi-frequency SAR data. The study areas include the tidal flats of Jebu Island and the reclaimed lands of Hwaong district on the western coasts of the Korean peninsula. SAR data of three frequencies were accordingly calibrated to provide precise backscattering coefficients through absolute radiometric calibration. The root mean square (RMS) height and the correlation length, which can describe the surface roughness, were extracted from the backscattering coefficients using the inversion of the Integral Equation Method (IEM). The IEM model was appropriately modified to accommodate the environmental conditions of tidal flats. Volumetric soil moisture was also simultaneously extracted from the dielectric constant using the empirical model, which define the relations between volumetric soil moistures and dielectric constants. The results obtained from the proposed algorithm were verified with the in-situ measurements, and we confirmed that multi-frequency SAR observations combined with the surface scattering model for tidal flats can be used to quantitatively retrieve the geophysical surface parameters in tidal flats.

Remote Sensing of Soil Moisture Change Using a Differential Interferometry Technique (차분 간섭 기법을 이용한 지표면 수분함유량 변화 탐지)

  • Park, Sin-Myeong;Oh, Yisok
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
    • /
    • v.24 no.4
    • /
    • pp.459-465
    • /
    • 2013
  • This paper presents a differential interferometry technique for soil moisture change detection by measuring surface-height variation. COSMO-SkyMed SAR images were used to verify the DInSAR(differential interferometric SAR) technique. The soil penetration depth changes according to soil moisture, that causes phase change of the received signal. The height of soil surface and its displacement can be detected by a radar interferometry technique using phase difference of two received signals. To retrieve displacement variation, one of three SAR images is used as a reference image. Reference image and other two images are processed by the differential interferometry technique in the same area. The soil moisture was measured for the test sites to verify the DInSAR technique. The penetration depth is calculated by using the in-situ measured soil moisture data and it is compared with the displacement values acquired by the DInSAR technique.

A Study on the Heat and Moisture Transport Properties of Vapor-Permeable Waterproof Finished Fabrics for Sports Wear (스포츠웨어용 투습방수직물의 열·수분이동 특성에 관한 연구)

  • Son, Bu Hun;Kim, Jin-A;Kwon, Oh Kyung
    • Fashion & Textile Research Journal
    • /
    • v.2 no.3
    • /
    • pp.220-226
    • /
    • 2000
  • This study was to determine the characteristics of vapor-permeable waterproof finished fabric by the coating method. 4 different kinds of coating fabrics (A : wet, porous, polyurethane, B : dry, no porous, polyurethane, C : shape memory polyurethane and D : dry, porous polyurethane) were used, which were developed recently With this sample, moisture transport rate ($40^{\circ}C$, 45%RH & $40^{\circ}C$, 95%RH), changes of coating side's shape by washing times, water repellency rate, contracted length, qmax, heat conductivity, heat keeping rate, heat keeping rate with cotton, heat keeping rate on humidity temperature and humidity within clothing etc. were checked. And it was done in a climate chamber under $20{\pm}2^{\circ}C$, $65{\pm}5%RH$. The results of this study were as follow; In the moisture vapor transmission of sample B and C increased on high temperature and high humidity while sample A and D decreased, on this condition. Qmax rate had high relation with ground fabric's surface properties and the order was A>C>D>B. Heat conductivity had high relation with thickness and surface properties. Heat keeping rates on sweat condition showed around half percents of heat keeping rates on normal condition, but had no relation with moisture vapor transport rate. Changes of the fabric's properties by washing times were different in accordance with the construction of fabrics and the coating resin. Sample C had tow heat keeping rate on the high temperature and humidity and high heat keeping rate on the low temperature and humidity Moisture transport rate of vapor-permeable waterproof finished fabrics had high relation with the properties of ground fabrics on low humidity condition, but on the high humidity condition, it was highly related with the properties of coating resin.

  • PDF

RNN-LSTM Based Soil Moisture Estimation Using Terra MODIS NDVI and LST (Terra MODIS NDVI 및 LST 자료와 RNN-LSTM을 활용한 토양수분 산정)

  • Jang, Wonjin;Lee, Yonggwan;Lee, Jiwan;Kim, Seongjoon
    • Journal of The Korean Society of Agricultural Engineers
    • /
    • v.61 no.6
    • /
    • pp.123-132
    • /
    • 2019
  • This study is to estimate the spatial soil moisture using Terra MODIS (Moderate Resolution Imaging Spectroradiometer) satellite data and machine learning technique. Using the 3 years (2015~2017) data of MODIS 16 days composite NDVI (Normalized Difference Vegetation Index) and daily Land Surface Temperature (LST), ground measured precipitation and sunshine hour of KMA (Korea Meteorological Administration), the RDA (Rural Development Administration) 10 cm~30 cm average TDR (Time Domain Reflectometry) measured soil moisture at 78 locations was tested. For daily analysis, the missing values of MODIS LST by clouds were interpolated by conditional merging method using KMA surface temperature observation data, and the 16 days NDVI was linearly interpolated to 1 day interval. By applying the RNN-LSTM (Recurrent Neural Network-Long Short Term Memory) artificial neural network model, 70% of the total period was trained and the rest 30% period was verified. The results showed that the coefficient of determination ($R^2$), Root Mean Square Error (RMSE), and Nash-Sutcliffe Efficiency were 0.78, 2.76%, and 0.75 respectively. In average, the clay soil moisture was estimated well comparing with the other soil types of silt, loam, and sand. This is because the clay has the intrinsic physical property for having narrow range of soil moisture variation between field capacity and wilting point.

Evaluation of Compaction Quality using High-resolution Terrain Factor and Soil Moisture (고해상 지형정보와 토양수분을 활용한 다짐도 평가)

  • Kim, Sung-Wook;Go, Daehong;Lee, Yeong-Jae;Choi, Eun-Kyeong;Kim, Jin-Young;Kim, Ji-Sun;Cho, Jin-Woo
    • Journal of Environmental Science International
    • /
    • v.31 no.10
    • /
    • pp.869-881
    • /
    • 2022
  • In this study, a field study was conducted to investigate the relationship between high-resolution remote images and the volumetric moisture, and the number of compaction. Changes in the shape of the surface and soil moisture content were observed and correlated with the number of compactions using roller equipment. As the compaction is repeated, the surface is flattened and the terrain curvature decreases and converges to zero. In particular, the tangential curvature changes as the number of compactions increase. Due to soil compaction, the vegetation index changed from a positive to a negative value, and most of the test site area was homogenized with a negative index. This suggests a decrease in porosity and an increase in volumetric water content associated with increasing soil compaction. Soil moisture, measured using a frequency domain reflectometry(FDR) sensor, tends to increase proportionately with the number of vibration compactions, but the correlation between the number of compactions and soil moisture is unclear. This study suggests that while it is necessary to consider the reproducibility of the experiments performed, the compaction quality of the soil can be evaluated using high-resolution terrain factors and soil moisture.