• Title/Summary/Keyword: Moisture Level

Search Result 1,311, Processing Time 0.033 seconds

Measurements of Mechanical Behavior of Rough Rice under Impact Loading (벼의 충격(衝擊) 특성(特性)에 관한 연구(硏究))

  • Cha, J.Y.;Koh, H.K.;Noh, S.H.;Kim, M.S.;Kim, Y.H.
    • Journal of Biosystems Engineering
    • /
    • v.14 no.3
    • /
    • pp.207-214
    • /
    • 1989
  • In this study, impact force and angular displacement of the pendulum were measured by the load cell and potentiometer. Mechanical behavior of rough rice under impact loading was able to analyze precisely and efficiently, because measured data were accumulated and handled by the automatic data acquisition system making use of microcomputer system. Impact force and angular displacement were measured with a resolutiln of 1/1500 seconds in time. Mechanical behavior such as force and energy at rupture point of Japonica type and Indica type rough rice were measured with this system. After impact loading, the damage of rough rice was examined with the microphotograph and an allowable impact force was measured. The results obtained in this study are summarized as follows. 1. Machanical behavior of rough rice under impact loading was analyzed precisely and efficiently because measured data were accumulated and handled by this data acquisition system. 2. Rupture force and rupture energy of rough rice were appeared to be the lowest value in the range of 16 to 18 % moisture content, and rupture force and rupture energy of Japonica type were higher than those of Indica type in each level of moisture content. 3. From the result of the damage examined after the impact loading, allowable impact force was the lowest in the range of 16 to 18 % moisture content, and the value of the allowable impact force of Japonica type was higher than that of Indica type in each level of moisture content.

  • PDF

Analysis of the Effects of Drainage Systems in Wetlands Based on Changes in Groundwater Level, Soil Moisture Content, and Water Quality (지하수위, 토양수분함량 및 수질변화를 활용한 습윤화 지역의 배수시설 효과 평가)

  • Kim, Chang-Hoon;Ryu, Jeong-Ah;Kim, Deog-Geun;Kim, Gyoo-Bum
    • The Journal of Engineering Geology
    • /
    • v.26 no.2
    • /
    • pp.251-260
    • /
    • 2016
  • Groundwater flow due to hydraulic gradients across a geologic barrier surrounding a dam reservoir can cause swamps or wetlands to form on the downstream side of the dam, thereby restricting land use. The difference in head between the reservoir level and the downstream groundwater level creates a hydraulic gradient, allowing water to flow through the geologic barrier. We constructed a drainage system at the Daecheong dam to study the effects on groundwater levels and soil moisture contents. The drainage system consisted of a buried screened pipe spanning a depth of 1-1.5 m below a land surface. Groundwater levels were monitored at several monitoring wells before and after the drainage system was installed. Most well sites recorded a decline in groundwater level on the order of 1 m. The high-elevated site (monitoring well W1) close to the reservoir showed a significant decline in groundwater level of more than 2 m, likely due to rapid discharge by the drainage system. Soil moisture contents were also analyzed and found to have decreased after the installation of the drainage system, even considering standard deviations in the soil moisture contents. We conclude that the drainage system effectively lowered groundwater levels on the downstream side of the dam. Furthermore, we emphasize that water seepage analyses are critical to embankment dam design and construction, especially in areas where downstream land use is of interest.

Heats of Moisture Adsorption for Sunflower Nutmeat Products (해바라기 종실제품의 수분흡착열)

  • Mok, Chul-Kyoon;Hettiarachchy, N.S.
    • Korean Journal of Food Science and Technology
    • /
    • v.23 no.6
    • /
    • pp.656-660
    • /
    • 1991
  • Heats of moisture adsorption of the sunflower nutmeat products (ground nutmeat, meal, protein concentrate and protein isolate) were determined from their isosteres at temperatures 10, 20 and $30^{\circ}C$. The changes in the heat of adsorption with moisture level were analyzed by Hunter equation. The Hunter equation was valid for representing the relationship between the heat of adsorption and the moisture content for the sunflower nutmeat products, and the accuracy-of-fit increased as protein content of the materials increased. The heat of adsorption decreased as moisture content increased, but increased as protein content increased. The heats of adsorption were 11.8-10.6 kcal/mole for the ground nutmeat at 4-12% moisture (d.b.) and 12.4-11.0 kcal/mole for the protein isolate at 6-20% moisture (d.b.).

  • PDF

Compression Behavior of Wood Stud in Light Framed Wall as Functions of Moisture, Stress and Temperature

  • Park, Joo-Saeng;Lee, Jun-Jae
    • Journal of the Korean Wood Science and Technology
    • /
    • v.34 no.5
    • /
    • pp.19-28
    • /
    • 2006
  • There has been considerable research in recent times in light-timber med structures in fires. These structures have included horizontal (floor-like) panels in bending and walls under eccentric and approximately concentric vertical loading. It has been shown that compression properties are the most dominant mechanical properties in affecting structural response of these structures in fire. Compression properties have been obtained by various means as functions of one variable only, temperature. It has always been expected that compression properties would be significantly affected by moisture and stress, as well. However, these variables have been largely ignored to simplify the complex problem of predicting the response of light-timber framed structures in fire. Full-scale experiments on both the panels and walls have demonstrated the high level of significance of moisture and stress for a limited range of conditions. Described in this paper is an overview of these conditions and experiments undertaken to obtain compression properties as a functions of moisture, stress and temperature. The experiments limited temperatures to $20{\sim}100^{\circ}C$. At higher temperatures moisture vaporizes and moisture and stress are less significant. Described also is a creep model for wood at high temperatures.

Effects of Soil Moisture on Survival of Larger Black Chafer (Holotrichia morosa Waterhouse) Eggs and Larvae (토양 수분함량이 큰검정풍뎅이의 난 및 유충의 생존에 미치는 영향)

  • 김기황
    • Korean journal of applied entomology
    • /
    • v.30 no.1
    • /
    • pp.37-41
    • /
    • 1991
  • Laboratory experiments were conducted to examine the effects of soil moisture on the survival of the larger black chafer(Holotrichia morosa Waterhouse) eggs and larvae. Survival rates of eggs and 1st, 2nd, and 3rd instar larvae were all above 79% at soil moisture of 15% and 25% in sandy loam and clay loam soil, but decreased considerably at 5% and 35%. At these extreme moistures there seem to be differences in survival rates of eggs and larvae between soil textures. Egg development was delayed as soil moisture approached to the lower limit for survival. Older eggs were tolerant to the high moisture stress(33-36 % , clay loam soil), and duration of the stress affected egg development. Feeding of 3rd instar larvae was obviously suppressed at the higher level of soil moisture.

  • PDF

Factors Influencing the Development of Pressure Ulcers in Surgical Patients (수술환자의 욕창발생 예측요인에 관한 연구)

  • Park, Hyoung-Sook;Park, Kyung-Yeon;Yu, Sung-Mi
    • Journal of Korean Academy of Nursing
    • /
    • v.35 no.1
    • /
    • pp.125-134
    • /
    • 2005
  • Purpose: The purpose of this study was to identify the influencing factors on the development of pressure ulcers in patients undergoing surgery which lasted more than two hours. Method: One hundred nineteen surgical adult patients were included in the study. Data was measured on each participant from December 2003 to February 2004. It was collected using a structured researcher-administered sheet and analyzed by descriptive statistics, t-test, chi-square test and logistic regression analysis. Result: The prevalence of a perioperative pressure ulcer was 26.1%. The level of moisture, friction and shear, length of surgery, and perioperative irrigation were significantly higher in the pressure ulcer group than those in the non-pressure ulcer group. The level of activity and level of consciousness were significantly lower in the pressure ulcer group than those in the non-pressure ulcer group. Significant influencing factors on the development of pressure ulcer were 'moisture' and 'irrigation' and those variables explained 23.1% of varience in the development of a pressure ulcer during surgery. Conclusion: It is necessary to develop a strategy to prevent pressure ulcer by taking 'moisture' and 'irrigation' into account during the preoperative, perioperative and postoperative period.

Improvement of Quality Stability of Red Ginseng by Gamma Irradiation (홍삼의 품질안정성 향상을 위한 감마선의 이용)

  • 권중호;변명우;장석도;이광승
    • Food Science and Preservation
    • /
    • v.6 no.1
    • /
    • pp.23-28
    • /
    • 1999
  • Commercial red ginseng, which was manufactured for the past 6 years, showed a microbial level of 2.0${\times}$10\ulcorner to 7.2${\times}$10\ulcorner CFU/g of total aerobic bacteria and molds. The moisture content of commercial products was ranged from 13.54 to 17.26%, which were higher than that of the product standard, 14%. Irradiation of red ginseng at 2.5 kGy resulted in the reduction of microorganisms contaminated to below the detectable level. Irradiation prevented mold growth on red ginseng during storage at RH 90% and 25$^{\circ}C$; molds were found at the 72nd day after storage in 2.5 kGy-irradiated sample, while 41st day in the nonirradiated control. At this point of time, irradiated samples showed an increased level of moisture content required for mold growth, 22.2% in 2.5 kGy group and 21.5% in control group. Based on the above results, microbiological qualities of red ginseng could be effectively improved by the optimum dose of irradiation, which was expected to secure the quality stability of red ginseng during distribution under the high-moistured conditions.

  • PDF

Design and Application of Subsurface Drainage Devices for Multipurpose Farmland

  • Jeon, Jong Gil;Choi, Yong Hun;Kim, Min Young;Kim, Young Gjin
    • Journal of Biosystems Engineering
    • /
    • v.42 no.4
    • /
    • pp.265-275
    • /
    • 2017
  • Purpose: This study aims to identify the most stable boring shape among the circle, square, and inverted-triangle types in order to be applied to the development of a tractor-pulled underdrain boring device. Methods: The underdrain boring devices designed with the circle, inverted triangle, and square types were analyzed by numerical analysis, and they were evaluated by soil moisture and underground water level in the test field. Results: The results of the numerical analysis indicated that the increases in displacement, and strain when a uniform load is placed on the surface soil with soil weight were in the order of the inverted-triangle type, square type, and circle type. The soil moisture content and the underground water level after rainfall showed the largest difference in the order of the circle type, square type, and inverted-triangle type, indicating that the circle type had the largest drainage effects after rainfall. Conclusions: The overall findings of this study show that the circle type is the most stable among the circle, square, and inverted-triangle types.

Comparison of Surface Fuel and Soil Layer Moisture after Rainfall in Broad-Leaved Forest at Young Dong Region (영동지역 활엽수림에서의 강우 후 지표연료의 습도변화 분석)

  • Kwon, Chun-Geun;Lee, Si-Young;Lee, Hae-Pyeong
    • Fire Science and Engineering
    • /
    • v.26 no.1
    • /
    • pp.49-60
    • /
    • 2012
  • The change in fuel moisture in accordance with the number of days after rainfall is an important factor in predicting forest fire dangers and supporting forest fire rangers. Therefore, in order to clear up these forest fire occurrence conditions, forest fire danger levels for surface fuel 0.6 cm or lower, 0.6~3.0 cm, 3.0~6.0 cm, and 6.0 cm or above by fallen leaves layer, humus layer, soil layer, and diameter after rainfall of 5.0 mm and higher in accordance with tree density in 2008, 2009 Spring/Autumn Young Dong region have been analyzed. Research showed an approximate 17 % fuel moisture which is a dangerous forest fire occurrence level after 5 days from rainfall in medium-density areas and 3 days after rainfall in loose-density areas of Spring time in the fallen leaves layer. On the other hand, the humus layer showed a 40 % or higher fuel humidity even after 6 days from rainfall regardless of the season, while the upper and lower parts of the soil layer had a little change. In loose-density areas with 0.6 cm or less surface fuel per diameter in Spring time, the fuel humidity displayed a dangerous level in fire forest occurrence after 3 days, and 4days in medium-density areas, and for loose-density areas with 0.6~3.0 cm surface fuel per diameter in Autumn time it showed a dangerous level in forest fire occurrence after 3 days, and for medium-density areas, 5 days. In the case of 3.0~6.0 cm of fuel moisture per diameter in both Spring and Autumn times, even after 6 days, low and medium-density areas showed that they maintain fuel moisture and therefore the dangers of forest fires were very low, and in the case of 6.0 cm or higher, it showed 25 % or higher fuel moisture even after 6 days from rainfall regardless of the season.

Modeling the effects of excess water on soybean growth in converted paddy field in Japan 1. Predicting groundwater level and soil moisture condition - The case of Biwa lake reclamation area

  • Kato, Chihiro;Nakano, Satoshi;Endo, Akira;Sasaki, Choichi;Shiraiwa, Tatsuhiko
    • Proceedings of the Korean Society of Crop Science Conference
    • /
    • 2017.06a
    • /
    • pp.315-315
    • /
    • 2017
  • In Japan, more than 80 % of soybean growing area is converted fields and excess water is one of the major problems in soybean production. For example, recent study (Yoshifuji et al., 2016) suggested that in the fields of shallow groundwater level (GWL) (< 1m depth), rising GWL even in a short period (e.g. 1 day) causes inhibition of soybean growth. Thus it becomes more and more important to predict GWL and soil moisture in detail. In addition to conventional surface drainage and underdrain, FOEAS (Farm Oriented Enhancing Aquatic System), which is expected to control GWL in fields adequately, has been developed recently. In this study we attempted to predict GWL and soil moisture condition at the converted field with FOEAS in Biwa lake reclamation area, Shiga prefecture, near the center of the main island of Japan. Two dimensional HYDRUS model (Simuinek et al., 1999) based on common Richards' equation, was used for the calculation of soil water movement. The calculation domain was considered to be 10 and 5 meter in horizontal and vertical direction, respectively, with two layers, i.e. 20cm-thick of plowed layer and underlying subsoil layer. The center of main underdrain (10 cm in diameter) was assumed to be 5 meter from the both ends of the domain and 10-60cm depth from the surface in accordance with the field experiment. The hydraulic parameters of the soil was estimated with the digital soil map in "Soil information web viewer" and Agricultural soil-profile physical properties database, Japan (SolphyJ) (Kato and Nishimura, 2016). Hourly rainfall depth and daily potential evapo-transpiration rate data were given as the upper boundary condition (B.C.). For the bottom B.C., constant upward flux, which meant the inflow flux to the field from outside, was given. Seepage face condition was employed for the surrounding of the underdrain. Initial condition was employed as GWL=60cm. Then we compared the simulated and observed results of volumetric water content at depth of 15cm and GWL. While the model described the variation of GWL well, it tended to overestimate the soil moisture through the growing period. Judging from the field condition, and observed data of soil moisture and GWL, consideration of soil structure (e.g. cracks and clods) in determination of soil hydraulic parameters at the plowed layer may improve the simulation results of soil moisture.

  • PDF