• Journal of Ecology and Environment
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• 제42권2호
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• pp.77-84
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• 2018

Background: For understanding and evaluating a more realistic and accurate assessment of ecosystem carbon balance related with environmental change or difference, it is necessary to analyze the various interrelationships between soil respiration and environmental factors. However, the soil temperature is mainly used for gap filling and estimation of soil respiration (Rs) under environmental change. Under the fact that changes in precipitation patterns due to climate change are expected, the effects of soil moisture content (SMC) on soil respiration have not been well studied relative to soil temperature. In this study, we attempt to analyze relationship between precipitation and soil respiration in temperate deciduous broad-leaved forest for 2 years in Gwangneung. Results: The average soil temperature (Ts) measured at a depth of 5 cm during the full study period was $12.0^{\circ}C$. The minimum value for monthly Ts was $-0.4^{\circ}C$ in February 2015 and $2.0^{\circ}C$ in January 2016. The maximum monthly Ts was $23.6^{\circ}C$ in August in both years. In 2015, annual precipitation was 823.4 mm and it was 1003.8 mm in 2016. The amount of precipitation increased by 21.9% in 2016 compared to 2015, but in 2015, it rained for 8 days more than in 2016. In 2015, the pattern of low precipitation was continuously shown, and there was a long dry period as well as a period of concentrated precipitation in 2016. 473.7 mm of precipitation, which accounted for about 51.8% of the precipitation during study period, was concentrated during summer (June to August) in 2016. The maximum values of daily Rs in both years were observed on the day when precipitation of 20 mm or more. From this, the maximum Rs value in 2015 was $784.3mg\;CO_2\;m^{-2}\;h^{-1}$ in July when 26.8 mm of daily precipitation was measured. The maximum was $913.6mg\;CO_2\;m^{-2}\;h^{-1}$ in August in 2016, when 23.8 mm of daily precipitation was measured. Rs on a rainy day was 1.5~1.6 times higher than it without precipitation. Consequently, the annual Rs in 2016 was about 12% higher than it was in 2015. It was shown a result of a 14% increase in summer precipitation from 2015. Conclusions: In this study, it was concluded that the precipitation pattern has a great effect on soil respiration. We confirmed that short-term but intense precipitation suppressed soil respiration due to a rapid increase in soil moisture, while sustained and adequate precipitation activated Rs. In especially, it is very important role on Rs in potential activating period such as summer high temperature season. Therefore, the accuracy of the calculated values by functional equation can be improved by considering the precipitation in addition to the soil temperature applied as the main factor for long-term prediction of soil respiration. In addition to this, we believe that the accuracy can be further improved by introducing an estimation equation based on seasonal temperature and soil moisture.

• 한국농공학회지
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• 제8권2호
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• pp.1193-1199
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• 1966

More stable and higher yields in rice paddy depend mainly upon an adequately balanced supply of water for higher yield. Rice paddy is supplied naturally by rainfall but inevitably requires artificial supplenental irrigation for higher yields. Even though it may be true that the water requirement of rice plants is generally higher than those of other crops, the submerged condition is not necessarily required for rice. The moisture requirements of rice vary according to its growing stages and it is possible to increse the irrigation efficiency by means of lessening the loss due to percolation and evapolation in the field. This experiment was conducted on the effect of the various amount of water supply and different irrigation periods for yield and yield components, and was carried out to find out the most suitable irrigation method and to increase the irrigation efficiency for higher yields in rice paddy. Randomized block design with 3 replications was employed where the 3 levels of the amount of irrigation water; (120% moisture contents), unirrigated (90~100%) and more un irrigated candition (80~90% moisture content), and levels of the various irrigation periods; usual, initial, intermediate and final periods, being treated. The results obtained in this experiment are as follows: 1. As for the physical and chemical and soil properfies, and other characteristics, there are no differences among the treatments enough to be effective for the growth of rice plants. 2. Culm length was measured after harvest as shown in table 2. 3. Difference of the amount of irrigation water did not change the culm length and ear length, however it also indicated more apparent increase in final treatment plots thatn that of usual. 3. No difference in the number of ears and number of ears pers per hill was founded treatments both in the difference of water supply and in the various irrigation periods. 4. There is no difference in the maturing rate and 1000 grains weight. 5. The number of panicles and grains and more increased in 80~100% moisture contents soil than those of 120%. and it shows in un irrigated plots, more irrigated plots and control plots in turn. Other wise according to the period\ulcorner of irrigation the trend is appeared in turn initial, usual, final and intermediate treatments.6. Yield as shown in table 7. 8 was more increased in unirrigated plots(90~IOO% moisture content) than the control plots (120% moisture content) by up to 8.2% and also 3. 2% in more unirrigated plots than that of control by periods is shown: usual plots final, initial, inter mediate treatment plots in turn. 7. The above resutts lead to the conclusion that no remarkable, differences in yields and soil properties are made by the unirrigation. However, it is apparent that this treatment has .some advantages in the points that one could spare the amount of water supply for irrigation with more increase in yield. In addition, a higher temperature and a brisk oxygen supply would be possible throug h this treatments. Accordingly, these treatment would be a more reasonable and economical cultivation method of rice for the better harvest.

• Transactions on Electrical and Electronic Materials
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• 제13권6호
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• pp.273-277
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• 2012

The vacuum drying process for drying of paper in current transformers was modeled with an aim to develop an understanding of the drying mechanism involved and also to predict the water collection rates. A molecular as well as macroscopic approach was adopted for the prediction of drying rate. Ficks law of diffusion was adopted for the prediction of drying rates at macroscopic levels. A steady state and dynamic mass transfer simulation was performed. The bulk diffusion coefficient was calculated using weight loss experiments. The accuracy of the solution was a strong function of the relation developed to determine the equilibrium moisture content. The actually observed diffusion constant was also important to predict the plant water removal rate. Thermo gravimetric studies helped in calculating the diffusion constant. In addition, simulation studies revealed the formation of perpetual moisture traps (loops) inside the CT. These loops can only be broken by changing the temperature or pressure of the system. The change in temperature or pressure changes the kinetic or potential energy of the effusing vapor resulting in breaking of the loop. The cycle was developed based on this mechanism. Additionally, simulation studies also revealed that the actual mechanism of moisture diffusion in CT's is by surface jumps initiated by surface diffusion balanced against the surrounding pressure. Every subsequent step in the cycle was to break such loops. The effect of change in drying time on the electrical properties of the insulation was also assessed. The measurement of capacitance at the rated voltage and one third of the rated voltage demonstrated that the capacitance change is within the acceptance limit. Hence, the new cycle does not affect the electrical performance of the CT.

• 한방안이비인후피부과학회지
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• 제25권3호
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• pp.129-149
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• 2012

Objective : The purpose of this study is to investigate the effect of cosmetic cream containing Samwhangsejegamibang Extracts on Atopic dermatitis patients. Methods : A total of 51 patients who visited Wonkwang Oriental Medical Center from April 8th, 2011 to October 8th, 2011 were included in this study. In this study, the patients were treated with Samwhangsejegamibang (experimental group) and placebo group. We observed scorad index, IGA, moisture content of skin, oil content of skin, wrinkled skin and hematological examination for 4 weeks. Results : 1. Comparison of changes in Scorad Index, depending on the perspective, the experimental group showed a statistically significant decline than the placebo group. 2. Comparison of change in IGA, depending on the perspective, the experimental group showed a statistically significant decline than the placebo group. 3. Comparison of change in moisture content, oil content of skin and wrinkled skin, both the experimental group and the placebo group showed level elevation but there was no statistically significant change. 4. Comparison of change in IgE and Eosinophil, both the experimental group and the placebo group showed no statistical significance. Conclusions : Considering the above experiments, it is suggested that cosmetic cream containing Samwhangsejegamibang extracts have a positive effect on atopic dermatitis patients.

• 한국식품영양과학회지
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• 제30권2호
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• pp.199-203
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• 2001

Chopi, Zanthaxylum piperitum DC., has been used as natural spice traditionally in the Far East countries including Korea. This study was performed with the object of providing basic data, firstly for the decision of the appropriate harvesting time for traditional use of chopi and secondly for developing a new spice satisfying the national dietary custom from chopi as raw material. Concerning the conte수 and its change of the proximate composition, the content of moisture and crude protein decreased in all sample, while the content of fiber and ash tended to increased with the lapse of harvest time. The content of mineral elements tended to increase in every sample with the lapse of harvest time, and contents of K and P were higher than that of Ca, Na and Mg. Every sample showed the highest content of 15~16 components of total amino acids at the first period and the content decreased gradually with the lapse of harvest time. On the basis of the first period, every sample showed the highest content of aspartic acid, the lowest content of methionine and the trace of cysteine. Free amino acids increased considerably with the lapse of harvest time for peels of chopi and minchopi broth, while the amount for leaves increased on the contrary.

• 한국식품조리과학회지
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• 제25권5호
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• pp.586-592
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• 2009

Sulgidduk samples containing 2, 4, and 8% red ginseng powder and a control[ED highlight - consider specifying what the control was, if 0%, then change to Sulgidduk samples containing 0(control), 2, 4 and 8%] were examined for moisture content, color, gelatinization properties, textural characteristics, and sensory qualities to determine the optimal ratio of red ginseng powder in the formulation. The moisture contents among the samples did not differ significantly. Specifically, they ranged from 39.64 to 40.69%, and increased as the red ginseng powder content increased. Additionally, the lightness decreased and the yellowness and redness increased as the red ginseng powder content increased. Evaluation of the gelatinization properties revealed that the, peak viscosity(P), hold viscosity(H), final viscosity(F), setback, and time to peak viscosity decreased with increasing red ginseng powder content, but the breakdown and temperature to peak viscosity did not differ significantly among samples[ED highlight - please ensure my changes are correct]. The hardness and adhesiveness decreased with increasing red ginseng powder content, as did the cohesiveness, gumminess, and chewiness; however, the springiness did not differ significantly among samples. Sulgidduk containing 4% red ginseng received the highest scores for flavor, taste, texture and overallquality. Based on the above results of the sensory and texture analyses, Sulgidduk containing 4% red ginseng had the highest quality[ED highlight - please ensure my changes are correct].

• 한국연초학회지
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• 제8권1호
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• pp.69-78
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• 1986

This experiment was carried out to Investigate the environmental changes of rhizosphere, behavior of nutrient components in soul, and nutrients uptake and growth response of the tobacco plant in the condition that mulch as polyethylene film, had been removed on the ridge at the 50th day after transplanting in comparison with continuous mulching condition. The results obtained were as follows; 1. After rainfall, soil moisture content In the plow layer was greatly increased without mulch in comparison with that of the plot with mulch. As a result, leaf water potential of tobacco plant without mulch was higher than that with mulch. 2. Available nutrients such as $NH_4-N, \;NO_3-N$, and total salts in the plow layer of the plot without mulch tended to be Increased, and especially accumulated on the surface layer owing to the redistribution of soil water by rainfall during the latter growth stage after removing mulch. 3. Nutrients uptake by tobacco was much more enhanced in the plot without mulch and resulted in higher contents of total nitrogen, $NO_3-N, \;P_2O_5, \;and K_5O$ in the tobacco leaf Especially higher content of nitrogen caused the delay of maturity resulting In the increased of dry weight of top part of tobacco in the plot without mulch toned to be Increased in comparison with that in mulching condition. Content of total nitrogen, $NO_3-N$, and nicotine in flue-lured leaves was much higher in the plot without. mulch than in mulching condition, but lower content of reducing sugar in the plot without mulch resulted in lower quality of tobacco.

• 한방안이비인후피부과학회지
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• 제21권3호
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• pp.124-131
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• 2008

Objectives : The aim of this study was conducted to test dry infant skin by external application with herbs in cosmetics. Methods : A total of 25 infants who visited Daegu Hanny Oriental Medical Center from March 5th, 2008 to May 18th, 2008 were included in this study. In this study, they were treated with the cosmetic products(body wash, rotion, cream) containing herbs. For 4 weaks skin moisture content was measured by corneometer ClVI825. And satisfaction after using body wash, rotion, cream was checked. Results : There were no significant differences on sex and age. Change of skin moisture content between before treatment and after treatment (2, 4 weeks) showed significant changes(p<0.05). Satisfaction after using body wash, rotion, cream was near good. Conclusions : Considering the above results, we have concluded that cosmetics containing herbs have the remarkable effect on infant skin mosturizing.

• 임산에너지
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• 제18권2호
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• pp.84-91
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• 1999

The objective of this study was to present creep and the effects of mechano-sorptive deflection of drift pin moment resisting joint between LVL members under changing relative humidity (RH) conditions. The LVL members with steel gusset were jointed by a square pattern of eight injected drift pin. Three diameter drift pins were used to test specimens (6mm, 10mm, and 16mm). The creep test was conducted under two constant loading conditions : one at 30 kgf(840 kgf-cm) and the other at 60 kgf(1680 kgf-cm). The experiment was conducted in an open shed outside. (1)The total rotation creep model of moment resisting joing can be expressed as the sum of the creep of controlled environment (3-parameter model), dimensional change and mechano-sorptive deflection resulting from the variable environment. (2)Mechanosorptive rotation creep is recoverable as moisture content increases during adsorption. Least squares method for linear regression analysis was performed using mechano-sorptive rotation creep as the dependent variable and moisture content as the independent variable. The slope of low moment specimens are compared with those of high moment. This means that low moment condition is more easily affected by changes in humidity than high moment conditions. (3)Although creep deflection is higher for small diameter drift pin than for large diameter drift pin, the shape of creep deflection curves for all specimens is similar.

• Environmental Analysis Health and Toxicology
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• 제6권3_4호
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• pp.133-141
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• 1991

Vermistabilization is the stabilization of organic wastes using earthworms. The worms maintain aerobic conditions in the waste, accelerating and enhancing the biological decomposition of the waste. This study was carried out to find out fundamental factors affecting the performance of the process such as temperature, moisture content and pH condition of nightsoil sludge, and to evaluate the worms excreta (casting) as fertilizer. The results could be summarized as follows; the optimum range of temperature was observed 10~3$0^{\circ}C$ while survival rate of eathworm decreased rapidly at 35$^{\circ}C$ within 6 days and death occurred at 5$^{\circ}C$. Those of moisture content and pH condition were 50~70% and 5~8, respectively. Earthworms were revealed to change the composition of N in nightsoil sludge consisting of$NH_3$-N (71%), $NO_2$-N (2%) and $NO_3$-N (27%) into that $NH_3$-N (24%), $NO_2$-N (1%), $NO_3$-N (75%) in earthworm excreta, respectively The concentrations of NH$_3$and H$_2$S gas in pig manure were reduced by 59.2% and 45.2% in case of mixing pig manure with casting.