• 한국농공학회논문집
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• 제58권2호
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• pp.65-71
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• 2016

The new concept of agricultural water supply potential, which is mean annual turnover rate times unit storage capacity, was introduced for agricultural reservoirs. We investigated characteristics of mean annual turnover rate and unit storage capacity for agricultural reservoirs with storage capacity of over $1million\;m^3$. The curve of agricultural water supply potential represents change in mean annul turnover rate according to change in unit storage capacity. The mean annual turnover rate and unit storage capacity in the reservoirs with high minimum storage ratio are significantly higher than those in the reservoirs with low minimum storage ratio. Most of unstable water supply reservoirs showed low mean annual turnover rate or low unit storage capacity, indicating that mean annual turnover rate may be an index of stability degree for agricultural water use. The reservoirs with mean annual turnover rate of over 2 and unit storage capacity of over 0.8 m may be estimated as the stable water supply zone for 10 frequency dry year. The reservoirs with high agricultural water supply potential can belong to the wide range of stable water supply zone. The results suggest that relation between mean annual turnover rate and unit storage capacity may be used in evaluating stability degree for agricultural water supply in the reservoirs.

• 동아시아식생활학회지
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• 제14권3호
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• pp.265-274
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• 2004

To investigate the effect of cereal powders on the quality and storage characteristics of sausage, Aw, pH, microbial count, TBA value, VBN value, textual and sensory characteristics were examined. Water activity tended to decrease as storage time prolonged and all the samples showed higher Aw's than that of the control. During the storage period, pH values of all the samples decreased. L, a and b values had a tendency to decrease during the storage period. During the four weeks storage at 4$^{\circ}C$, TBA and VBN values of all the sample showed increasing tendency and were lower than those of the control. Total plate counts of bacteria, the number of lactic acid bacteria and coliform bacteria counts increased as the storage time prolonged. Texture characteristics of all samples increased up to 1 week storage and decreased subsequently. The sensory scores of all the samples decreased as the storage time prolonged.

• 설비공학논문집
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• 제14권1호
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• pp.31-37
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• 2002

This paper is concerned with the development of a new method for making and separating ice and saving floated ice by installing an evaporation plate at in-water within a storage tank. In a conventional harvest-type ice storage system, a tank saves ice by separating a formed ice from an installed evaporation plate, which is located above an ice storage tank as an ice storage system. A new harvest-type method shows very good heat transfer efficiency than a convectional method. It is because the evaporation panel is directly contacted with water in a storage tank. Also, at a conventional system a circulating pump, a circulating water distributor and a piping are installed, but these components are not necessary in a new method. In this study two kinds of ice storage systems are experimentally investigated to study the thermal characteristics of ice storage tanks. The results showed discharge of cold capacity of new type indicated the high values about 30~40% based on five time of drive, the temperature difference of inlet/outlet occurred the big range about $1.3^{\circ}C$. So, the new type which makes ice in water showed superiorly.

• Water Engineering Research
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• 제4권2호
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• pp.69-85
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• 2003

Previously developed empirical equations used to calculate the parameters of the transient storage model are analyzed in depth in order to evaluate their behavior in representing solute transport in the natural streams with storage zone. A comparative analysis of the existing theoretical and experimental equations used to predict parameters of the transient storage (TS) model is reported. New simplified equations for predicting 4 key parameters of the TS model using hydraulic data sets that are easily obtained in the natural streams are also developed. The weighted one-step Huber method, which is one of the nonlinear multi-regression methods, is applied to derive new parameters equation. These equations are proven to be superior in explaining mixing characteristics of natural streams with the transient storage zone more precisely than the other existing equations.

• 한국환경과학회지
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• 제29권12호
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• pp.1199-1204
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• 2020

Lentinula edodes mushrooms cultivated under different relative humidities were wrapped at 4℃ and the results of storage characteristics were investigated. Changes in water content of fruiting bodies during the storage period showed the highest water content in fruit bodies harvested from the treatment with the highest relative humidity. The luminosity of the fresh fruiting bodies showed no significant change during the storage period, and the redness was higher in the relative humidity 95% treatment than in the other treatments. According to this study, the relative humidity of the pileus was 65%, and the content of Ergosterol was 0.67 ± 15 g / L at relative humidity of 65%, 80% and 95%. In addition, amino acid analysis and Principal Component Analysis (PCA) confirmed that methionine was the main cause of changes in storage time and relative humidity.

• 한국태양에너지학회 논문집
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• 제33권5호
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• pp.82-88
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• 2013

There are the stirring test and drain test in the daily performance test to determine the thermal performance of a domestic solar hot water system. The drain test is a test that measures the discharge heating rate while drain the hot water from the top of the storage tank and supply the city water to the bottom of the tank. From the perspective of the user, this drain test is more effective than the stirring test. In this study, the thermal performance were compared through the drain test for a passive type and an active type domestic solar hot water systems consisting of the same storage tank and collectors. At this point, a passive type was used the horizontal storage tanks, and an active type was used vertical storage tank. In the drain test, when the hot water drained up to the reference hot water temperature, an active type which have vertical storage tank represents excellent daily performance than a passive type which have horizontal storage tank regardless of weather conditions. The reason for this is because the vertical storage tank is advantageous to thermal stratification in the tank. After the drain test, the residual heat for the horizontal storage tank was much more than the vertical storage tank, but in the next day the amount of discharged heat were less than the those of vertical storage tank neither. Thus, the solar water heating system which have horizontal storage tank should be adopted preheating control method rather than separate using control method when connected with auxiliary heat source device.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집D
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• pp.298-303
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• 2001

A fundamental study on the under water harvest-type ice storage system and its temperature characteristics in ice storage system was performed experimentally. The experiments were conducted by changing the inlet refrigerant temperature of an evaporator to analyzing the thermal fluid motion inside the ice storage tank. From the experimental results, the cold storage characteristics were investigated by measuring the axial and radial temperature variations inside the ice storage tank with respect to the inlet and outlet refrigerant temperatures of an evaporator. In case of the under water harvest-type ice storage system, thermal fluid. motion inside the ice storage tank was shown differently in comparison with that of other ice storage systems. During the cooling storage process, there was no supercooling phenomenon in the ice storage tank. These results show the characteristic of this system and the possibility of application to other fields.

• 동아시아식생활학회지
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• 제12권3호
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• pp.249-257
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• 2002

This study was conducted to investigate the effects of medicinal plants with additives on storage characteristics of sausage. The water activity of the sausage with the additives tended to decrease with the storage time: the highest value was shown in the Angelica added sausage samples, in both cases added with dried powder as well as with extracted powder. The Paeonia extract powder added sausage had the lowest pH value. The herbal plant added sausages showed the lowest cooking and storage losses among all. The values of TBA (thiobarbituric acid value) and VBN (volatile basic nitrogen) increased with storage time, but the values of the sample with the extract powder additive were lower than those of the freeze-dry powder additive. Total plate counts of bacteria increased with storage time fur all samples, but those for the samples with Pueraria, Platycodon, Angelica, Bupleurum and Paeonia additives exhibited lower values than the control. From the above results, the sausages with medicinal plant additives showed the superior storage safety and quality characteristics.

• 한국식품조리과학회지
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• 제24권3호
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• pp.282-293
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• 2008

The purpose of this study was to acquire basic data on Jeolpyun added with Baekbokryung powder to aid the product's commercial production. Initially a sensory test was performed with consumers to the identify preferred amount of Baekbokryung powder to add according to age. The results revealed that those in their 20's to 40's preferred the 3% treatment, while those 50 and older preferred the 5% treatment. Next, the optimum water content of Jeolpyun was chosen by examining select quality characteristics in samples containing 20, 25, 30, 35 and 40% water while the amounts of added Baekbokryung powder were fixed at 3% and 5%, respectively, as based on the sensory panel results. For the color characteristics of the samples, lightness(L), redness(a) and yellowness(b) values increased in proportion to the added amount of water regardless of the Baekbokryung level. However, the ${\Delta}E$ values of the samples increased with storage time along with the darkening of their surfaces. The samples with high moisture contents, such as the 35 and 40% treatments, maintained a relatively softer texture during 24 hr of storage as compared to the other samples. Also noted was an initial slow increase in hardness up to 12 hr of storage, and then accelerated hardening until 24 hours of storage. Throughout the storage period, th 30% treatment received low scores: the 40% treatment was especially disliked in terms of mashing of the product due to the excess water. Overall, for a soft and moderately chewy product, the optimum Baekbokryung powder and moisture level for Jeolpyuns were suggested as 3 to 5% ranges and 35% respectively. Ultimately, the results of this research will contribute to the possible commercialization of a Jeolpyuns product that contains added Baekbokryung.

• 한국태양에너지학회 논문집
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• 제21권1호
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• pp.71-82
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• 2001

The heat transfer experiment in a latent heat storage tank as a solar energy storage system for the hot water supply was carried out. The latent heat storage tank was consisted of triple - tube type ; Outer shell for hot water from solar collector, PCM storage vessel in the middle of the tank and inside tube for hot water recovery. The heat storage tank has the dimension of 60 cm long and 34 cm outside diameter. Paraffin wax(m.p = 55.4C) and sodium acetate trihydrate(m.p = 58 C) were employed as the PCM this study. Experimental variables were inlet temperature and flow rate of the hot water for heat storage stage and cold water for heat recovery stage. Temperature profiles, heat transfer coefficient and the efficiency of heat storage$(Q/Q_{max})$ and heat recovery $(Q/Q_{max})$ were determined for the paraffin wax and inorganic salt respectively.