• Title/Summary/Keyword: moisture content change

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Drying Characteristics of Barley and the Effect of Moisture Content and Drying Temperature on Milling Recovery (보리의 건조특성(乾燥特性)과 건조온도(乾燥温度) 및 함수율(含水率)이 정맥수율(精麥收率)에 미치는 영향(影響))

  • Lee, Yong Kook;Kim, Sam Do;Park, Seung Je
    • Journal of Biosystems Engineering
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    • v.8 no.2
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    • pp.62-68
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    • 1983
  • This study was to examine the drying characteristics of barley and the effect of moisture content of barley on milling performance. A barley variety, Jogang, having 35.0% of initial moisture content was used for this experiment. Thermo-hydrostatic dryer which consists of blower, condensor, heater, humidifier, drying chamber and control box, etc., was used for the drying experiment. The change in the weight of a barley sample was continuously measured by means of the ring type load cell installed inside the drying chamber. Milling test runs the samples having the predetermined moisture content were taken from each drying test run. A laboratory type barley miller was used for the milling test. The results of the study are summarized as follows: 1. The drying constants (k) applied for the thin layer drying model, (M-Me)/(Mo-Me) = $Ae^{-kt}$ were 0.155, 0.259 and 0.548, respectively, at the three levels of drying temperatures, $40^{\circ}C$, $50^{\circ}C$ and $60^{\circ}C$. The drying constants complied with the Arrhenius Equation, K = Ko exp (-C/T), were determined as $Ko=1.901455{\times}10^8$ and C = 6563. 2. The laboratory milling test indicated that the highest milled and head barley recovery was resulted from the sample which was dryed at $40^{\circ}C$. In general, the increase in the drying temperature from $40^{\circ}C$ to $60^{\circ}C$ indicated a negative effect on milling yields. 3. Also, the sample having 15% M.C. presented the highest milled and head barley recovery among the five moisture content levels (12, 15, 18,21 and 24%).

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Effects of Moisture Content on Recrystallization of Rice Starch Gels (쌀전분겔의 재결정화에 미치는 수분함량의 영향)

  • Baik, Moo-Yeol;Kim, Kwang-Joong;Cheon, Ki-Cheol;Ha, Yeon-Chul;Kim, Wang-Soo
    • Korean Journal of Food Science and Technology
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    • v.29 no.5
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    • pp.939-946
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    • 1997
  • Effects of moisture content on the gelatinization and recrystallization of non-waxy and waxy rice starch gels were investigated by differential scanning calorimetry (DSC). The recrystallization rates of the starch gels containing various moisture contents $(40{\sim}70%)$ were analyzed by Avrami equation. The waxy rice starch had higher gelatinization temperature and enthalpy than non-waxy one. The highest degrees of recrystallization in both rice starch gels stored at $4^{\circ}C$ were shown at 40%, and recrystallizations above 80% moisture content were not found. The degree of recrystallization of waxy one was higher than that of non-waxy one in the range of 40 to 60% moisture content. The Avrami exponents (n) of both rice starch gels were near to 1.0 and the time constant (1/k) was increased with increasing moisture content in the range of 40 to 70% moisture content. The recrystallization rate of waxy rice starch gel was slower than that of non-waxy one. The recrystallization of rice starch gels could be explained by the change of ice melting enthalpy during storage. The Wg's, represented the maximum practical amount of plasticizing water, were about 29.9% and 28.2% for non-waxy and waxy rice starch gels, respectively.

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Changes in Compositions of Pacific Saury(Cololabis seira) Flesh during Drying for Production of Kwamaegi 1. Changes in General Composition and Lipid Components (과메기 제조시 건조조건에 따른 꽁치(Cololabis seira) 근육의 성분 변화 1. 일반성분 및 지질조성 변화)

  • 최경호;오승희;김덕진
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.27 no.3
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    • pp.386-392
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    • 1998
  • Experiments were carried out to establish an effective artificial drying method of Pacific saury (Cololabis seira) to kwamaegi. Raw fish containing 67% moisture were dried up to containing less than 40% moisture by drying for 15 days. The fish lost moisture more rapidly during first 3 days of natural drying than artificial drying. Total lipid content increased from 16.1% to 30.3 and 29.8% by 15 days of natural and artificial drying, respectively. Neutral lipid occupying 91.63% of total lipid increased to 92~94% during 15 days of drying, while content of phospholipid and glycolipid decreased slightly. The values of peroxide and thiobarbituric acid increased up to 6 days of drying and then did not change. Peroxide levels were lower in artifically dried fish than in naturally dried ones.

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Physicochemical and Sensory Textural Properties of Rice Extrudate Depending on Extrusion Conditions

  • Chung, Kang-Hyun
    • Preventive Nutrition and Food Science
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    • v.5 no.1
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    • pp.25-31
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    • 2000
  • Extrusion conditions for production of rice extrudate were studied. The optimal production conditions of rice extrudate were determined by the relationship between dependent variables such as expansion ratio, shear strength and color change and independent variables such as moisture content of raw material, screw speed, and die tem-perature of extruder. The textural quality of rice exturdate was significantly affected by the moisture content of raw material (x1), screw speed (x2), and die temperature (x3) of extruder. The expansion ratio of rice extrudate showed the highest value at the moisture content of 18% of raw material, and the lowest at 24%, and whose regression equation was Y=34.8967 - 3.219X1 - (0.623$\times$10-2)X2 + 0.136X3 + (0.648$\times$10-1)X12 + (0.138$\times$10-3)X1X2 + (0.456$\times$10-4)X22 + (0.719$\times$10-3)X1X3 -(0.515$\times$10-3)X2X3- (0.552$\times$10-3)X32. The most desirable texture of rice extrudate determined by shear test and sensory evaluation was obtained at the following conditions : mois-ture content of 18% of raw material, screw speed of 210 rpm and die temperature of 11$0^{\circ}C$. The rice extrudate prepared under the above conditions showed the lowest shear force of 954g at which the highest sensory score was obtained.

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Suggestion and Evaluation for Prediction Method of Landslide Occurrence using SWAT Model and Climate Change Data: Case Study of Jungsan-ri Region in Mt. Jiri National Park (SWAT model과 기후변화 자료를 이용한 산사태 예측 기법 제안과 평가: 지리산 국립공원 중산리 일대 사례연구)

  • Kim, Jisu;Kim, Minseok;Cho, Youngchan;Oh, Hyunjoo;Lee, Choonoh
    • Journal of Soil and Groundwater Environment
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    • v.26 no.6
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    • pp.106-117
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    • 2021
  • The purpose of this study is prediction of landslide occurrence reflecting the subsurface flow characteristics within the soil layer in the future due to climate change in a large scale watershed. To do this, we considered the infinite slope stability theory to evaluate the landslide occurrence with predicted soil moisture content by SWAT model based on monitored data (rainfall-soil moisture-discharge). The correlation between the SWAT model and the monitoring data was performed using the coefficient of determination (R2) and the model's efficiency index (Nash and Sutcliffe model efficiency; NSE) and, an accuracy analysis of landslide prediction was performed using auROC (area under Receiver Operating Curve) analysis. In results comparing with the calculated discharge-soil moisture content by SWAT model vs. actual observation data, R2 was 0.9 and NSE was 0.91 in discharge and, R2 was 0.7 and NSE was 0.79 in soil moisture, respectively. As a result of performing infinite slope stability analysis in the area where landslides occurred in the past based on simulated data (SWAT analysis result of 0.7~0.8), AuROC showed 0.98, indicating that the suggested prediction method was resonable. Based on this, as a result of predicting the characteristics of landslide occurrence by 2050 using climate change scenario (RCP 8.5) data, it was calculated that four landslides could occur with a soil moisture content of more than 75% and rainfall over 250 mm/day during simulation. Although this study needs to be evaluated in various regions because of a case study, it was possible to determine the possibility of prediction through modeling of subsurface flow mechanism, one of the most important attributes in landslide occurrence.

Effect of Air Circulation Velocity on the Rate of Lumber Drying in a Small Compartment Wood Drying Kiln (소형 목재인공건조실에 있어서 공기순환속도가 목재건조율에 미치는 영향)

  • Chung, Byung-Jae
    • Journal of the Korean Wood Science and Technology
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    • v.2 no.2
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    • pp.5-7
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    • 1974
  • 1. This study indicates that above the fiber saturation point the drying rate can be increased with increasing the velocity of the air circutation, i.e., the drying rate of sample boards is proportional to the air velocity, but below the fiber saturation point, the effect of the velocity of air circulation is very low as shown in Figs. 1 and 2. 2. Under the controlled temperature and humidity in the kiln, the more the sample boards have moisture, the higher drying rate of it can be obtained. In other words, this means that even though in the case of drying various moisture content of wood, at the final drying stage, approximately the same percentage of moisture content of wood can be secured by employing the higher velocity of air circulation. 3. This study shows that the rate of drying in kiln changes distinctly at the fiber saturation point, i, e., above the fiber saturation point, the drying curve shows concave aginst the X axsis, but below the fiber saturation point, in the range from 30 percent of moisture content to 20 percent of moisture content, the curve shows convex as shown in Fig. 3. As the drying progresses, however, the drying curve shows concave again below 20 percent of moisture content. This means that inflection point of drying curve may be located clearly at the fiber saturation point, i.e., 30 percent of moisture content. As mentioned above, the 30 percent of moisture content of wood at which the inflectional point appears can be recognized as a critical point, i. e., the fiber saturation point at which all free water was removed from wood. The existence of inflectional point indicates that the evaporation of hygroscopic water in a cell wall is more difficult than the evaporation of free water in a cell cavity and the minor space of cell wall. The convex curve in the range of moisture content from 30 percent to 20 percent means that the evaporation of capillary condensed water has a tendency of the same rates of drying approximately, but as approaching to the 20 percent of moisture, the transfusion of moisture from wood becomes difficult because of having less moisture in cell wall. Below 20 percent of moisture content, the drying curve shows concave again, which means that it is difficult to remove the moisture located nearer to the surface of cellulose molecules and the surface bound water. These relations were revealed in Fig. 4. In comparison AC curve which does not have the two inflection points with BD curve which has two inflection points, i.e., Band D, they are mentioned already, by existence of the inflection points, the curve BD shows that the change of drying rate in the interval from 20 percent of moisture content to 30 percent of moisture content is not greater than in the case of the curve AC in the same interval. At the inflection point of 30 percent of moisture content, it can be noticed that the changing of the drying rate is very conspicuous. This phenomenon also can be recognized, as it is noticed by the Fig. 3, the drying rate from green to 30 percent of moisture content is very great. But the inclination of the curve is very slow from 30 percent of moisture content to 20 percent of moisture content, i.e., the inclination of the curve becomes almost horizontal lines. Acknowledgments Gratitude is expressed to Fred E. Dickinson, Professor of 'Wood Technology, School of Natural Resources, University of Michigan, USA for his suggestion to carry out this study.

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Modeling and mapping fuel moisture content using equilibrium moisture content computed from weather data of the automatic mountain meteorology observation system (AMOS) (산악기상자료와 목재평형함수율에 기반한 산림연료습도 추정식 개발)

  • Lee, HoonTaek;WON, Myoung-Soo;YOON, Suk-Hee;JANG, Keun-Chang
    • Journal of the Korean Association of Geographic Information Studies
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    • v.22 no.3
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    • pp.21-36
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    • 2019
  • Dead fuel moisture content is a key variable in fire danger rating as it affects fire ignition and behavior. This study evaluates simple regression models estimating the moisture content of standardized 10-h fuel stick (10-h FMC) at three sites with different characteristics(urban and outside/inside the forest). Equilibrium moisture content (EMC) was used as an independent variable, and in-situ measured 10-h FMC was used as a dependent variable and validation data. 10-h FMC spatial distribution maps were created for dates with the most frequent fire occurrence during 2013-2018. Also, 10-h FMC values of the dates were analyzed to investigate under which 10-h FMC condition forest fire is likely to occur. As the results, fitted equations could explain considerable part of the variance in 10-h FMC (62~78%). Compared to the validation data, the models performed well with R2 ranged from 0.53 to 0.68, root mean squared error (RMSE) ranged from 2.52% to 3.43%, and bias ranged from -0.41% to 1.10%. When the 10-h FMC model fitted for one site was applied to the other sites, $R^2$ was maintained as the same while RMSE and bias increased up to 5.13% and 3.68%, respectively. The major deficiency of the 10-h FMC model was that it poorly caught the difference in the drying process after rainfall between 10-h FMC and EMC. From the analysis of 10-h FMC during the dates fire occurred, more than 70% of the fires occurred under a 10-h FMC condition of less than 10.5%. Overall, the present study suggested a simple model estimating 10-h FMC with acceptable performance. Applying the 10-h FMC model to the automatic mountain weather observation system was successfully tested to produce a national-scale 10-h FMC spatial distribution map. This data will be fundamental information for forest fire research, and will support the policy maker.

On the Population Dynamics and Interspecific Competition of Disporum smilacinum and D. viridescens (Liliaceae) in Mt. Nam Park (남산공원 내 애기나리와 큰애기나리 군락의 동태 및 종간 경쟁의 추정)

  • 민병미
    • The Korean Journal of Ecology
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    • v.21 no.5_3
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    • pp.649-663
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    • 1998
  • The clarify the ecological properties, and to predict change of understory vegetation of mt. Nam Park, population dynamics and interspecific competition of D. smilacinum and D. viridescens, which grow in understory of deciduous broad-leaved forest and pseudo-annuals, were studied from May 20 to May 30 1998. The depth of litter layer, soil moisture content, soil organic matter and soil texture were surveyed in 18 populations (15 D. smilacinum populations and 3 D. viridescens populations). Mean litter layer of d. smilacimum population was thinner than that of D. viridescens populations). Mean litter layer of D. smilacnum population was thinner than that of D. viridescens population. The contents of soil moisture and organic matter of D. smilacinum population were lower than that of D. viridescens population. The D. smilacinum growed in broad range of soil texture but D. viridescens in loamy soil. Because D. smilacinum could tolerate more broad range of soil moisture and soil texture than D. viridescens, the former covered the herb layer in earlier stage and the latter introduced in later stage when rhizome could grow easily. The numbers of individual in two marginal parts were smaller than that in center in same D. smilacinum patch. And the total numbers of individuals grown in (10 ${\times}$ 10)cm were from 0 to 12. The rhizome (subterranean runner) weight, rhizome length, root weight, shoot weight, lea weight and leaf number per subquadrat (cell) increased along the number of individual, that is, increased from marginal part to center. But rhizome weight and rhizome length per individual were vice versa. Therefore, the individuals in marginal part reproduced longer and stronger asexual propagules than that in center. The distribution pattern of D. smilacinum was contageous and that of D. viridescens was random or regular. Therefore, population growth of former was independent on density and that of latter was dependent on density. The distributions of size-class showed normal curves in two population, but the curves based on data of total dry weight showed positive skewness and those of leaf number showed negative skewness The correlation coefficient (CC) values between the properties of each organ were high in two population and significant at 0.1% level. The CC values of D. viridescens were higher of the two. Therefore, the former allocated the energy to each organ stable. The rhizome depth of d. viridescens was 2 times deeper than that of D. smilacinum. And rhizome length and weight of D. viridescens were longer (2 times) or heavier (4 times) than those of D. smilacinum. The patch size of D. viridescens increased 60 cm per year and that of D. smilacinum 30 cm. On this results, the intrinsic increase velocity of d. viridescens patch was 2 times faster than that of d. smilacinum, therefore, on the competition, the former had an advantage over D. smilacinum. The reason why d. viridescens defeated D. smilacinum resulted from that the leaf area of former was 4 times broader than that of latter. in Mt. Nam Park, it was thought that two disporum Population would change with the 3 thpes of environmental change as followings. First, no human impact and increase of soil moisture content resulted in increase of D. viridescens population. Second, mild human impact and similar condition of soil moisture content resulted in slow increase or no changes of D. smilacinum and d. viridescens population. Third, severe human impact and dry condition resulted in decrease or vanishment of two disporum populations.

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Effect of Herbal CP Soap on Facial Moisture (한약저온숙성비누가 얼굴수분에 미치는 영향)

  • CHoi, Sang Rak;Kim, Yun Young;Seo, Bu Il;Koo, Jin Suk
    • The Journal of Korean Medicine
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    • v.40 no.1
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    • pp.34-45
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    • 2019
  • Objectives : To maintain a healthy skin condition, the role of moisture in the stratum corneum is important. We use soap in our daily life, so we wanted to observe the changes of the skin moisture using herbal CP soap. Four kinds of herbal CP soaps were prepared and their effects on skin moisture were compared. Methods: We surveyed 39 students at A University to determine their subjective skin condition, lifestyle and washing habits. Then, a facial analysis test was performed. We made herbal CP soaps using Kyungohkgo, Hwangryunhaedoktang, Seosiokyongsan and Baeksoooh and distributed them to experiment participants. Prior to the experiment, their skin condition was checked and skin condition was assessed using Facial Diagnosis System three times in total. After the experiment, the change of skin was measured and analyzed. Results: As a result of examining the skin moisture according to the using of the herbal CP soap by the participants, the skin moisture was gradually increased compared with before use. The moisture content increased after 6 weeks of use compared to before using Seosiokyongsan, Hwangryunhaedoktang, Kyungohkgo CP soap compared to before use. But there was no significant difference between 3 weeks and 6 weeks of use compared to before use. As a result of using Baeksoo-oh CP soap, the skin moisture of the experimental participants was continuously increased. Conclusion: Natural CP soaps are believed to have a beneficial effect in increasing the moisture content of facial skin.

Control of Grade Change Operations in Paper Plants Using Model Predictive Control Method (모델예측제어 기법을 이용한 제지공정에서의 지종교체 제어)

  • Kim, Do-Hun;Yeo, Yeong-Gu;Park, Si-Han;Gang, Hong
    • Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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    • 2003.11a
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    • pp.230-248
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    • 2003
  • In this work an integrated model for paper plants combining wet-end and dry section is developed and a model predictive control scheme based on the plant model is proposed. Closed-loop process identification method is employed to produce a state-space model. Thick stock, filler flow, machine speed and steam pressure are selected as Input variables and basis weight, ash content and moisture content are considered as output variables. The desired output trajectory is constructed in the form of 1st-order dynamics. Results of simulations for control of grade change operations are compared with plant operation data collected during the grade change operations under the same conditions as in simulations. From the comparison, we can see that the proposed model predictive control scheme reduces the grade change time and achieves stable steady-state.

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