• Korean journal of food and cookery science
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• v.21 no.3 s.87
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• pp.339-345
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• 2005

This study was carried out to determine the changes of chlorophyll contents in spinach during growth stages and storage with two packaging materials. The chlorophyll contents increased to a maximum level in the spinach leaves after 35 days of planting, while the level in the roots extremely decreased and that in the stems did not change during the growth period. The total chlorophyll content was higher in the leaves than that in the stems and roots. The ratios of chlorophyll a/b in the leaves and stems were almost similar to those reported for spinach elsewhere. When stored for 1, 3, and 5 days without packaging, the remaining percentage of chlorophyll was $96.29\%,\;90.79\%\;and\;85.74\%$, respectively, at $5^{\circ}C,\;and\;82.75,\;44.63,\;33.07\%$, respectively, at $20^{\circ}C$. The chlorophyll contents of the spinach stored in polyethylene bags were significantly higher than of that those without packaging and of that packaged with newspaper during storage. From the results, it was found that spinach packaged in polyethylene bags suppressed the degradation of chlorophyll and maintained the freshness during low temperature storage and that the chlorophyll contents increased during the growth period.

• Food Science and Preservation
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• v.19 no.6
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• pp.799-806
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• 2012

This experiment was conducted to establish the optimum conditions for high $CO_2$ gas treatment in combination with a proper gas-permeable packaging film to maintain the quality of fig fruit (Ficus carica L). Among the fig fruits with different high $CO_2$ treatments, the quality change was most effectively controlled during storage in the 70%-$CO_2$-treated fig fruit. Harvested fig fruit was packaged using microperforated oriented polypropylene (MP) film to maintain the optimum gas concentrations in the headspace of packaging for the modified-atmosphere system. MP film had an oxygen transmission rate of about $10,295cm^3/m^2$/day/atm at $25^{\circ}C$. The weight loss, firmness, soluble-solid content (SSC), acidity (pH), skin color (Hunter L, a, b), and decay ratio of the fig fruits were monitored during storage at 5 and $25^{\circ}C$. The results of this study showed that the OPP film, OPP film + 70% $CO_2$, and MP film+70% $CO_2$ were highly effective in reducing the loss rate, firmness and decay occurrence rate of fig fruits that were packaged with them during storage. In the case of using treatments with packages of OPP film and OPP film+70% $CO_2$, however, adverse effects like package bursting or physiological injury of the fig may occur due to the gas pressure or long exposure to $CO_2$. Therefore, the results indicated that MP film containing 70% $CO_2$ can be used as an effective treatment to extend the freshness of fig fruits for storage at a proper low temperature.

• Journal of the Korean Society of Marine Environment & Safety
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• v.26 no.6
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• pp.751-758
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• 2020

SCR technology, which uses urea-water as a NO_x reducing agent, has been widely used to reduce NO_x in marine diesel engines. However, as an alternative NO_x reducing agent, solid-phase ammonium carbamate has several advantages, such as low-temperature NO_x reduction performance and NH₃ storage capacity. This study presents a method for evaluating the purity of ammonium carbamate using EA, FTIR, and XRD to investigate the change in the material characteristics of ammonium carbamate when it is exposed to various temperature and pressure conditions. In this study, it was found that the purity of ammonium carbamate can be effectively evaluated via EA analysis. The FTIR analysis results confirmed that the properties of ammonium carbamate did not change even after repeated heating and cooling under thermal decomposition temperature conditions, which may be applied to the SCR system of marine diesel engines. Additionally, it was found that when ammonium carbamate was exposed to the atmosphere for a long time, it transformed into ammonium carbonate.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.1 no.2
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• pp.87-96
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• 1968

As the raw material of fish paste, the experiment on shark meats was conducted from July to December 1967 at the Fisheries Research and Development Agency, Pusan, Korea. The result and the conclusion obtained by the experiment are as follows. 1. Much salt-soluble protein was found in the shark meat comparing with to the other fish. 2. Deodorization of shark meat, using less than $0.05\%$ of acetic acid was most preferable for the elasticity and flexibility of its product. 3. Keeping raw material at low temperature was necessary in maintaining its elasticity. 4. In setting shark fish paste, keeping the raw material at $35-40^{\circ}C$ for 40-70 minutes was the most desirable condition. 5. The best temperature and the duration of heating were 40-60 minutes at $89-90^{\circ}C$, Meanwhile, heating at high temperature was preferable for the storage for a long period, but the elasticity and quality has decreased a little accordingly. 6. For the increase of its palatability, adding $30\%$ of yellow corvenia meat or $20\%$ sea eel meat were more preferable. 7. Pre ervation of the product for 20 days at $20^{\circ}C$ or 50 days at $5^{\circ}C$ was possible by adding $0.2\%$ potassium sorbinate to the product as antiseptic.

• Food Science of Animal Resources
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• v.24 no.2
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• pp.156-163
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• 2004

This study was carried out to investigate the improvement of stretchability in Mozzarella cheese based on the influence of various factors such as starter type, fat content, salt content and stretching temperature. To do this study, stretchability, meltability, fat leakage and the change of soluble nitrogen compound were measured during storage of the Mozzarella cheese at 4$^{\circ}C$ for 10 weeks. When L bulgaricus starter was added, stretchability of the cheese was excellent and cheese manufactured with starter of L bulgaricus and L. bulgaricus : Str. thermophilus = 1:2 improved meltability because of high soluble nitrogen compound. When salt content of cheese was 0.5％, this resulted in extreme deterioration of quality in regard to stretchability, meltability and fat leakage at five weeks and when salt content of cheese was 0.5, 1.0 and 1.5％, soluble nitrogen compound was 4.49, 4.45 and 2.61 ％ at one week and 19.71, 19.44％ and 17.07％ at eight weeks, respectively. Stretchability was good at high stretching temperature, and cheese with stretching at 60'C showed poor meltability at the first stage, but this cheese had good meltability in process of time because increase in soluble nitrogen compound was high at low stretching temperature.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.13 no.3
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• pp.623-628
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• 2009

The emergence of compact and low-power wireless communication sensors and actuators in the technology supporting the ongoing miniaturization of processing and storage allows for entirely the new kinds of embedded systems. These systems are distributed and deployed in environments where they may have been designed into a particular control method, and are often very dynamic. Collection of devices can communicate to achieve a higher level of coordinated behavior. Wireless sensor nodes deposited in various places provide light, temperature, and activity measurements. Wireless sensor nodes attached to circuits or appliances sense the current or control the usage. Together they form a dynamic and multi-hop routing network connecting each node to more powerful networks and processing resources. Wireless sensor networks are a specific-application and therefore they have to involve both software and hardware. They also use protocols that relate to both applications and the wireless network. Wireless sensor networks are consumer devices supporting multimedia applications such as personal digital assistants, network computers, and mobile communication devices. Wireless sensor networks are becoming an important part of industrial and military applications. The characteristics of modem embedded systems are the capable of communicating adapting the different operating environments. In this paper, We designed and implemented sensor network system which shows through host PC sensing temperature and humidity data transmitted for wireless sensor nodes composed wireless temperature and humidity sensor and designs sensor nodes using embedded system with the intention of studying USN.

• Journal of Conservation Science
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• v.37 no.1
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• pp.63-76
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• 2021

The purpose of this study is to scientifically analyze physicochemical characteristics of the roof tiles used for palaces in the Joseon Dynasty which stored in Changdeokgung material storage and Seooreung Jaesil and the modern handmade ones which made by N company to understand the differences between their manufacturing techniques. Through chromaticity, cross-sectional observation, component analysis, and crystal structure analysis, it was possible to confirm the physicochemical properties and fired properties of the roof tile. Roof tiles from the Joseon Dynasty have a wider colorimetric range and higher apparent porosity and water absorption, on average, than the modern roof tiles. The cross section of the Joseon Dynasty roof tiles shows that most clay minerals have not been vitrified, remaining in the form of atypical particles, while the modern roof tiles have denser clay materials. X-ray diffraction analysis identified low-temperature minerals such as micas in Joseon roof tiles but no peak of these minerals was observed in the modern roof tiles, implying that the modern ones are fired at higher temperature than the Joseon ones. Therefore, the modern roof tiles are fired at higher temperature and have higher density than the Joseon ones due to the use of pugmills. The general content of main ingredients was similar between the two. Additionally, the principal component analysis of trace elements in the Joseon roof tiles showed that most samples were from similar areas. It seems that the Joseon roof tiles were manufactured using soils supplied from a specific region at the same timeframe and their consistency in the content of principal components implies that they also have similar mix proportions of clay.

• Korean Journal of Breeding Science
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• v.41 no.4
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• pp.496-501
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• 2009

In order to promote the efficiency of strawberry breeding programs, pollen viability of strawberry, 'Seolhyang' was investigated using the fluorochromatic reaction test and seed set under controlled environment. Pistil receptivity was also assessed by hand pollination. Four varieties including 'Maehyang' were used for the test of pistil receptivity with 'Seolhyang' as a pollen parent. Pollen viability remained high for several days under dry conditions as below 33% relative humidity while the greatest loss of viability occurred at 76% relative humidity. The viability was rapidly decreased at high humidity and almost all grains were unviable in 7 days after storage. Pollen viability does not appear to be drastically reduced if the relative humidity is low. Therefore, humidity is more important factor than temperature for the pollen viability in Fragaria${\times}$ananassa. The rate of seed set by hand pollination lasted higher than the average of 77.2% from 2 to 8 days after emasculation when the daily average temperature was around $15^{\circ}C$ in plastic house. It began to decline gradually from 10 days and had decreased dramatically after 12 days except several cultivars. Based on the daily mean accumulated temperature, it is recommended to have an artificial pollination between the range of $45{\sim}140^{\circ}C$ after the emasculation to increase the rate of seed set in strawberry.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.3
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• pp.269-277
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• 1995

This experiment was conducted to study on forage utility of native grasses in polderland for salt tolerance plant selection and good feed with collection and evaluation. As the result of investgate, it was carried out feed evaluation, germination physiology and early growth at the different salt content of Puccinellia coreesis Honda and P. nipponica Ohwi from May 1993 to June 1994. Germination physiology of the grasses was light and low temperature favored optimum germination temperature was 1$0^{\circ}C$, germination period was 30 days. Dormancy awakening was needed wet and high temperature condition with 1~3 days storage. Germination rate increased 18.0% of P. coreensis and 39.0% of P. nipponica than those of non treatments. Early growth condition of different salt content was good also at in 1.00% and 0.50% levels of P. coreensis and P. nipponica. Crude protein content was 8.4% at P. coreensis, 7.1% at P. nipponica and 10.3% of Italian ryegrass, and NFE content was arrangement in order of P. coreensis, Italian ryegrass and P. nipponica. TDN content was not different between P. coreensis, P. nipponica and Italian ryegrass. Also P. coreensis and P. nipponica have a good taste for cattle as same as other crops.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.24 no.2
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• pp.85-89
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• 2018

The effects of distribution temperature due to season all changes on quality and storability of baby leaf beet (Beta vulgaris L.) was examined in modified atmosphere (MA) packages. The beet leaf had been harvested at the 10 cm leaf length stage and packaged with an oxygen transmission rate (OTR) film of $1,300cc{\cdot}m^{-2}{\cdot}day^{-1}{\cdot}atm^{-1}$ and then held at 4 different distribution temperatures which were $-2^{\circ}C$, $4^{\circ}C$, $20^{\circ}C$, or $30^{\circ}C$ for 5 hrs and then stored for 18 days at $8^{\circ}C$. The loss of fresh weight of packged baby leaf beet was lowest at the $4^{\circ}C$ treatment, and below 0.6% in all distribution temperature treatments. The atmosphere composition in packages did not show any significant differences among treatments. The oxygen conc. was the highest at 18.0% after the $4^{\circ}C$ treatment, carbon dioxide conc. showed the maximum value of 4% at the $30^{\circ}C$ and $-2^{\circ}C$ treatments, and ethylene conc. was highest at the $10^{\circ}C$ treatment after 10 days in storage. The hardness was the highest at the $4^{\circ}C$ treatment on the final storage day. The $4^{\circ}C$ treatment showed the highest visual quality and the lowest off-odor and aerobic plate count. Therefore, it is necessary to establish a low-temperature distribution system which is controlled under $4^{\circ}C$, because the baby leaf beet's storability and microbial growth are effected even during a short time of 5 hrs during the distribution process.