• Journal of Biosystems Engineering
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• v.27 no.1
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• pp.39-44
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• 2002

In order to obtain the information of bio-environment control, the thermal characteristics of soil in the greenhouse heated by the heat pump and latent heat storage system were experimentally analyzed. The experimental systems were composed of the greenhouse with a heat pump and a latent heat storage system (system I), the greenhouse with a heat pump (system II), the greenhouse with a latent heat storage system (system III), and the greenhouse without auxiliary heating system (system IV). The thermal characteristics experimentally analyzed in each system were temperature of soil layers, soil heat storage and release, soil heat capacity and soil heat storage ratio. The results could be summarized as follows. 1. Time to reach the highest temperature at 20cm deep in soil layers of the crop routs in case of system I was shown to be delayed by 6 hours in comparison to the time of the highest temperature at the soil surface. 2. In the clear winter days, the stored heat capacity values fur the system I and the system II were shown to be 22.3% and 11.0% higher than the released heat capacity respectively, and the stored heat capacity values for the system III and the system IV were shown to be 6.2% and 29.6% lower than the released heat capacity respectively This confirms that the system I provided the best heat storage effect. j. The heat quantity values stored or released were shown to be highest at 5 cm depth of soil layers. And it was reduced with increasing of depth of soil layers until 20 cm and was not changed under the soil layer of 20 cm depth. 4. The heat absorption rates of soil, the ratio between supplied and stored heat energy, fur both the system I and system II were lower than 23%.

• Korean journal of food and cookery science
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• v.23 no.4 s.100
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• pp.502-510
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• 2007

This study investigated the utilization of turmeric (Curcuma aromatica Salab.) for tofu manufacture and its effects on the quality characteristics and shelf-life. Various concentration (0.000%, 0.005%, 0.010%, and 0.015%) of turmeric were used to evaluate the shelf-life during tofu storage for 12 days at $10^{\circ}C$. The pH decreased with an increasing storage period, but the 0.010% and 0.015% tofu showed lower pH value than the 0.000% tofu, the acidity decreased with an increasing storage period. The water content of the turmeric tofu decreased with an increasing storage period. The turbidity gradually increased until 6 days of storage, and then rapidly increased at 12 days of storage. The microbial count of the 0.015% tofu was lowest during the storage period. In measuring the turmeric tofu color, the L- and a--values decreased during the storage period, while the b--value increased. In the texture analysis, hardness, gumminess, and brittleness of the turmeric tofu decreased 12 days of storage. Cohesiveness and springiness increased with an increasing storage period. In the sensory evaluation, Smoothness, after taste, and overall taste were highest for the 0.010% tofu. For the overall acceptability, the 0.010% tofu (with 0.45% mixed coagulant) attained the highest score.

• Journal of Korean Society of Forest Science
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• v.85 no.1
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• pp.66-75
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• 1996

This study was carried out to examine the forest fire effect on water storage characteristics in the forests. Water storage capacity of the burned area was analyzed by several major factors, such as soil pore, maximum water content, effective water storage, and percolation rate. The results obtained from the analysis of major factors are as follows; The deeper soil depth, the less total pore, coarse pore, effective water storage, and percolation rate. However, fine pore increased slightly in both burned area and control plot. As compared with control plot, burned area showed lower percolation rate, coarse pore, and effective water storage, but higher values of fine pore. Directly after forest fire, the soil pore is little affected. But as the time passes, top soil structure changes and soil pore also is affected even in a deep soil. Estimated effective water storage was lower at top soil of Namcheon and at deep soil of Namha in all the burned areas, but slowly decreased in deep soil compared to control plots. Therefore it was concluded that forest water storage capacity was greatly affected by the forest fire.

• Food Science and Preservation
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• v.30 no.3
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• pp.369-382
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• 2023

We examined the changes in the physicochemical quality characteristics and antioxidant activity of fresh-cut Fuji apples (Malus pumila) during processing and storage after treatment with browning inhibitors. The primary aim was to elucidate processing suitability and storability. We observed that in the processing stage of slicing fresh Fuji apples, there were no significant differences in 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azinobis (3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radical scavenging ability and ferric-reducing antioxidant power (FRAP). However, after NaClO treatment, total flavonoid and total polyphenol contents decreased. When freshcut Fuji apples were treated with browning inhibitors and stored at 4℃, the L value and hardness decreased; however, the weight loss rate increased based on the storage period of all fruit groups treated with Citrus unshiu Markovich (CuM), calcium ascorbate (CA), and ascorbic acid (AA). The pH increased after 2 days of storage in 1% CuM and after 6 days of storage in 1% CA; however, no changes in pH were observed during the storage period in 1% AA. The DPPH radical scavenging activity was generally good under storage conditions of 1% AA at 4℃ and 1% CA at 20℃. Furthermore, FRAP remained relatively constant under storage conditions of 1% CA. The quality characteristics and antioxidant activity of fresh-cut fruits during processing and storage can be used as basic data for industries. Furthermore, we can gain confidence in quality improvements by improving the production and distribution environment of fresh-cut agricultural products.

• Food Science of Animal Resources
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• v.44 no.1
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• pp.189-203
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• 2024

This study investigated the antioxidant activity of radish seed oil (RSO) and its effects on the quality and storage characteristics of pork patties. To assess the antioxidant capacity of RSO, this study analyzed fatty acid composition, peroxide value (PV), and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity. Pork patties were manufactured with the addition of RSO-0.4%, 0.8%, 1.6%, and 2.4%-and measured in terms of proximate composition, pH, water holding capacity (WHC), cooking loss (CL), color, texture profile analysis, and a sensory evaluation. Total microbial count (TMC), volatile basic nitrogen (VBN), thiobarbituric acid reactive substances (TBARS), and PV were measured at 1, 3, and 7 days of refrigerated storage. The DPPH radical scavenging activity of RSO was found to be 75.46%. In the cases of WHC and CL, there was no significant differences observed between RSO0.4%, RSO0.8%, and positive control (PC; p>0.05). Meanwhile, RSO2.4% showed significantly lower hardness, springiness, gumminess, and chewiness than PC (p<0.05), and these values tended to decrease with the addition of increasing RSO. In terms of storage characteristics, with an increase in the amount of RSO added, TMC, VBN, TBARS, and PV all decreased; among the treatment groups, RSO2.4% showed the lowest values. In conclusion, RSO exhibits antioxidant activity, but when added in large amounts, it negatively affects the quality characteristics of patties while positively impacting their storage properties, thus necessitating a balanced consideration of both outcomes. Therefore, adding 1.6% RSO is considered to be the most appropriate level for formulations to be used in practice.

• Journal of Biosystems Engineering
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• v.30 no.3 s.110
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• pp.155-160
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• 2005

The objective of this research was to establish a domestically available cooling storage technique by cold-air in winter, using winter cool air ventilation fur determining rough rice cooling method in the storage and dry bin. The rough rice storage characteristics of two test conditions, winter cool-air ventilation storage and ambient temperature storage, were evaluated from January to July 2001, using a storage and dry bin of 300-ton capacity. Results of this research are as follows: Grain temperature was from $-5.1\~-8.5^{\circ}C$ after winter cool-air ventilation, and grain initial temperature for ambient temperature bin storage was $0.3\~1.9^{\circ}C$. Moisture content of rough rice decreased from $0.28\;to\;0.93\%$ and from $1.53\;to\;1.92\%$ to compare with original moisture contents for winter cool-air ventilation, and for ambient temperature bin storage, respectively. Broken ratio of brown rice from winter cool-air ventilation bin increased from $0.16\;to\; 0.92\%$, and brown rice broken ratio was from $2.24\;to\;2.86\%$ for ambient temperature bin storage to compare with initial broken ratio. Hardness of stored rice increased along storage period increase in alt storage methods, and cooling bin storage increased rice hardness of 0.271kgf: this increasing was lower then the other methods from 0.059 to 2.239kgf. Germination rates were decreased approximately 9.03, 3.14 and $3.20\%$ for upper, middle, and bottom of ventilating winter air bin, respectively, and germination rates of 2.70, 3.47 and $4.14\%$ were approximately decreased for upper, middle, and bottom parts of ambient temperature bin storage, respectively.

• The Korean Journal of Food And Nutrition
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• v.22 no.4
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• pp.587-597
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• 2009

Peeled chestnuts were stored at different temperatures($-10^{\circ}C$ and $-20^{\circ}C$) and after blanching at $90^{\circ}C$ for different lengths of time(0, 10, and 20 min) for 6 months. After the storage period, the texture, color, DSC and sensory characteristics were analyzed. Hardness, fracturability and chewiness increased with storage time, whereas springiness and cohesiveness decreased. Additionally, the L* decreased and a* and b* increased with storage time. Analysis of the DSC revealed that the peak of the retro gradation was approximately $46{\sim}60^{\circ}C$ and enthalpy for the peak increased with storage time. Additionally, the increment of enthalpy for samples stored at $-20^{\circ}C$ and blanched was lower than that of samples stored at $-10^{\circ}C$ and non-blanched samples. The sensory evaluation scores were also higher for samples stored at $-20^{\circ}C$ and blanched samples than for those stored at $10^{\circ}C$ and non-blanched samples.

• Water Engineering Research
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• v.4 no.2
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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.

• Solar Energy
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• v.20 no.3
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• pp.1-9
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• 2000

In these days the hot water circulating Ondol using the fossil fuel boiler is the heating system for the most of the Korean residents. Then it is installed without the heat storage medium in the Ondol heating layer, but the Korean traditional Ondol had been composed with the heat storage medium. The Ondol room without heat storage medium could not be comfortable because the room air temperature is not only changed unstably but also it has a defect too much fuel consumption. Therefore in this study the heat pump-latent heat storage Ondol as the new type of Ondol system was developed to solve these problems mentioned above, and the COP of the heat pump (Coefficient Of Performance), the latent heat storage characteristics in the new type of Ondol system and the temperature variation in the Ondol room with the ambient temperature were analyzed.

• Journal of the Korean Society for Precision Engineering
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• v.16 no.9
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• pp.149-158
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• 1999

The modern trends of optical storage devices can be characterized by high density in information recording, and high bandwidth in data input/output processing rate. These make servo engineers to face with a new barrier on control system design in much more difficult way. The first step to attack this barrier will be through a systematic modeling for the dynamic characteristics of optical storage drive. in this paper, an analytical dynamic model for an optical storage drive based on FEM is drived, and compared with experimental results. Through this comparison, a practical dynamic model on the focusing and tracking motion of optical storage drive is proposed for the initiation of real control system design problem.