• Title/Summary/Keyword: Moisture state

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SIMULATION OF SOIL MOISTURE VARIABILITY DUE TO CLIMATE ORANGE IN NORTHEAST POND RIVER WATERSHED, NEWFOUNDLAND, CANADA

  • A. Ghosh Bobba;Vijay P. Singh
    • Water Engineering Research
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    • v.4 no.1
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    • pp.31-43
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    • 2003
  • The impacts of climate change on soil moisture in sub - Arctic watershed simulated by using the hydrologic model. A range of arbitrary changes in temperature and precipitation are applied to the runoff model to study the sensitivity of soil moisture due to potential changes in precipitation and temperature. The sensitivity analysis indicates that changes in precipitation are always amplified in soil moisture with the amplification factor for flow. The change in precipitation has effect on the soil moisture in the catchment. The percentage change in soil moisture levels can be greater than the percentage change in precipitation. Compared to precipitation, temperature increases or decreases alone have impacts on the soil moisture. These results show the potential for climate change to bring about soil moisture that may require a significant planning response. They are also indicative of the fact that hydrological impacts affecting water supply may be important in consider-ing the cost and benefits of potential climate change.

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Composting of Organic Wastes by solid State Fermentation Reactor (Solid State Fermentation Reactor를 이용한 유기성 폐기물의 발효)

  • 홍운표;이신영
    • Microbiology and Biotechnology Letters
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    • v.27 no.4
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    • pp.311-319
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    • 1999
  • Leaves of Aloe vera Linne and bloods of domestic animal were composted in a soild state fermentation reactor (SSFR) by using microbial additive including a bulking and moisture controlling agent. From solid-culture of microbial additive, 10 species of bacteria and 10 species of fungi were isolated and, their enzyme activities including amylase, carboxy methyl cellulase CMCase, lipase and protease were detected. Optimum fermentation conditions of Aloe leaves and domestic animal bloods in SSFR were obtained from the studies of response surface analysis employing microbial additive content, initial moisture content, and fermentation temperature as the independent variables. The optimum conditions for SSFR using Aloe leaves were obtained at 9.45$\pm$73%(w/w) of microbial additives, 62.73$\pm$4.54%(w/w) of initial moisture content and 55.32$\pm$3.14$^{\circ}C$ of fermentation temperature while those for SSFR using domestic animal bloods were obtained at 10.25$\pm$2.04%, 58.68$\pm$4.97% and 57.85$\pm$5.$65^{\circ}C$, respectively. Composting process in SSFR was initially proceeded through fermentation and solid materials were decomposed within 24 hours by maintaining higher moisture level, and maturing and drying steps are followed later. After the fermentation step, the concentrations of solid phase inorganic components were increased while that of organic components were decreased. Also, concentrations of total organic carbon(TOC), peptides, amino acids, polysaccharides, and low fatty acids in water extracts were increased. As fermentation in composting process depends on initial C/N ratios in water extracts of two samples were increased because of increased water-soluble TOC. From these results, it was revealed that solid state fermentation reactor using microbial additives can be used in composting process of organic wastes with broad C/N ratio.

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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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Comparison of Equilibrium Moisture Contents for Conventional Kiln Dried- and High Temperature Dried Softwood Lumber by Moisture Content Determination (관행열기건조(慣行熱氣乾操)와 고온건조(高溫乾燥) 침엽수재(針葉樹材)의 함수율(含水率) 측정법(測定法)에 의한 평형함수율(平衡含水率) 비교(比較))

  • Jung, Hee-Suk;Smith, William B.
    • Journal of the Korean Wood Science and Technology
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    • v.22 no.4
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    • pp.37-42
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    • 1994
  • The adsorption of water vapor and equilibrium moisture content(EMC) of the specimens for four softwood species dried by conventional- and high temperature method and equilibrated to 15% of the target EMC condition at 25$^{\circ}C$ were determined by oven drying method and with moisture meters. The amount of adsorption for high temperature dried red pine was significantly higher than that of conventional kiln dried wood, while those of eastern white pine, eastern hemlock and Norway spruce were not significantly different between drying methods. EMCs of these four species determined by oven drying method and with capacitive admittance moisture meter were not significantly different between drying methods. EMC of high temperature dried red pine determined with resistance moisture meter was significantly higher than that of conventional kiln dried wood. But EMCs of other species did not show significant difference between drying methods. EMCs of conventional and high-temperature dried wood determined with electronic moisture meters, especially in the case of the capacitive-admittance moisture meter measurement, were lower than that determined by oven drying method.

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Automation of Solid-state Bioreactor for Oyster Mushroom Composting

  • Lee, Ho-Yong;Kim, Won-Rok;Min, Bong-Hee
    • Mycobiology
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    • v.30 no.4
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    • pp.228-232
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    • 2002
  • This study focused on the production of high quality compost for the growth of aero-thermophilic fungi, which has a promoting effect on the growth rate and production of oyster mushrooms. The automated solid-state bioreactor system was designed on the basis of a Three-Phase-One system, which controls the serial steps of prewetting, pasteurization and fermentation processes. High numbers of thermophilic fungi and bacteria were recovered from the mushroom composts prepared by this solid-state bioreactor. The rates of composting process were depended on physical as well as chemical factors. Among these factors, the parameters of moisture content and temperature were found to be particularly important. In our automated system, constant levels of moisture content, temperature and ventilation via mixing were provided by a centralized control apparatus including PLC, water tank and water jacket systems. These features induced higher microbiological activity of aero-thermophiles.

A simple practical method for determination of moisture transfer coefficient of mature concrete using a combined experimental-numerical approach

  • Chari, Mehdi Nemati;Shekarchi, Mohammad;Ghods, Pouria;Moradian, Masoud
    • Computers and Concrete
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    • v.18 no.3
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    • pp.367-388
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    • 2016
  • In this paper, a simple practical method is introduced in which a simple weight measurement of concrete and finite element numerical analysis are used to determine the moisture transfer coefficient of concrete with a satisfactory accuracy. Six concrete mixtures with different water-to-cementitious material (w/cm) ratios and two pozzolanic materials including silica fume and zeolite were examined to validate the proposed method. The comparison between the distribution of the moisture content obtained from the model and the one from the experimental data during both the wetting and drying process properly validated the performance of the method.With the proposed method, it was also shown that the concrete moisture transfer coefficient considerably depends on the pore water saturation degree. The use of pozzolanic materials and also lowering w/cm ratio increased the moisture transfer coefficient during the initial sorption, and then, it significantly decreased with an increase in the water saturation degree.

Critical Moisture and Pore Structure of Clay Based Consolidated Body (점토계 고형화소지의 임계함수율과 기공구조)

  • 이기강;박천주;김유택;김석범;김정환
    • Journal of the Korean Ceramic Society
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    • v.34 no.5
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    • pp.528-534
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    • 1997
  • There have been many studies on the preparation of slip, forming and drying in the slip casting process. However, is has not been yet on the rheological properties of consolidated body which largely affect on the workability. It was investugated that the rheological properties of the consolidated bodies formed by slip casting in the form of cakes from well dispersed(slip C) and weakly agglomerated slip(slip B) in the clay and clay-fly ash systems. The state of dispersion of slip was found to affected the critical moisture content which was largely affected by the pore and moisture distribution of the consolidated body. The cake C show lower critical moisture content than cake B in the clay system. However, the cake B gives lower critical moisture content than cake C in the clay-fly ash system.

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Comparative Analysis of Dynamic Moisture Movement Testers

  • Lee, Duck-Weon;Shim, Woo-Sub;Lim, Ho-Sun
    • Journal of Fashion Business
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    • v.15 no.6
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    • pp.40-55
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    • 2011
  • The purpose of this research is to review testing principle, testing design and experimental results of the four dynamic moisture movement testers. The research analyzes Moisture Manager Tester (MMT), Alambeta Instrument, Dynamic Surface Moisture Movement Tester, and Gravimetric Absorbent Testing Method based on American Society for Testing and Material (ASTM) E 96 which is an international standard testing method. Although many of researches use ASTM E 96 to measure moisture movement on a fabric, it has several weaknesses, such as long experimental time and a physical change of sample by a holder of the frame. Hence, lots of researchers have studied and developed the new measurement systems measuring moisture management on a fabric or garment and ultimately mimic heat energy and perspiration created by the human body. These moisture management systems use a variety of parameters, such as electricity, color, and sensor to measure their movement in the fabric. Through comparison with the existing tester (ASTM E 96), the research recognizes the strength and weakness in the dynamic moisture movement testers.

Monitoring of bridge overlay using shrinkage-modified high performance concrete based on strain and moisture evolution

  • Yifeng Ling;Gilson Lomboy;Zhi Ge;Kejin Wang
    • Structural Monitoring and Maintenance
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    • v.10 no.2
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    • pp.155-174
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    • 2023
  • High performance concrete (HPC) has been extensively used in thin overlay for repair purpose due to its excellent strength and durability. This paper presents an experiment, where the sensor-instrumented HPC overlays have been followed by dynamic strain and moisture content monitoring for 1 year, under normal traffic. The vibrating wire and soil moisture sensors were embedded in overlay before construction. Four given HPC mixes (2 original mixes and their shrinkage-modified mixes) were used for overlays to contrast the strain and moisture results. A calibration method to accurately measure the moisture content for a given concrete mixture using soil moisture sensor was established. The monitoring results indicated that the modified mixes performed much better than the original mixes in shrinkage cracking control. Weather condition and concrete maturity at early age greatly affected the strain in concrete. The strain in HPC overlay was primarily in longitudinal direction, leading to transverse cracks. Additionally, the most moisture loss in concrete occurred at early age. Its rate was very dependent on weather. After one year, cracking survey was carried out by vision to verify the strain direction and no cracks observed in shrinkage modified mixes.

Characterizing the Spatial-temporal Distribution of Soil Moisture for Sulmachun Watershed Through a Continuous Monitoring (설마천 유역의 토양수분 장기 모니터링을 통한 토양수분 시공간 변화양상의 특성화)

  • Lee, Ga Young;Kim, Ki Hoon;Kim, Sang Hyun
    • Proceedings of the Korea Water Resources Association Conference
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    • 2004.05b
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    • pp.209-214
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    • 2004
  • Time Domain Reflectometry with multiplex system has been installed to configure the spatial and temporal characteristics of soil moisture in a mountainous hillslope. An intensive surveying was performed to build a refined digital elevation model and flow determination algorithms with inverse surveying have been applied to establish an efficient soil monitoring system. Steady state wetness index, quasi-dynamic wetness index and fully dynamic wetness index have been calculated. Continuous monitoring of soil moisture data were analyized with wetness indices. Limitations and hydrological interpretations of this approach have beer discussed.

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