• Journal of The Korean Society of Agricultural Engineers
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• v.60 no.3
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• pp.1-13
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• 2018

Recently, the frequency and intensity of drought have been increasing due to the sudden abnormal climate in Korea. The occurrence of agricultural drought has been steadily increasing from 5 times in the 1980s to 2000s in 20 years, 6 times in the 10 years from 2000 to 2010, and 4 times in the recent period from 2011 to 2015. Therefore, this study analyzed the effect of water shortage caused by drought by improving the function of agricultural reservoir. The target area analyzed the data such as "Comprehensive Information System for Rural Water" operated by Korea Rural Community Corporation. As a result, we selected the target area as Wanju - gun, Jeollabuk - do in consideration of the rate of water storage compared with the normal 25 years, the completion year of the facility, the area of coverage per reservoir site and the low capacity. As a result of evaluating the improvement effect of agricultural facilities, it was analyzed that the irrigation area increased by about 25.7% when the water level was increased by 1m and the irrigation area increased by about 51.3% when the water level was increased by 2m. The results of the drought impact assessment after improving the function of the agricultural facilities were analyzed that it was effective to improve the function after more than 4m depth.

• Geophysics and Geophysical Exploration
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• v.8 no.2
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• pp.156-162
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• 2005

Particularly in research related to seawater intrusion the change of fluid electrical conductivity is one of major concerns, and effective monitoring can help to optimize a water pumping performance in coastal areas. Special considerations should be given to the mounting of sensors at proper depth during the monitoring design since the vertical distribution of fluid electrical conductivity is sensitive to the characteristics of seawater intrusion zone. This tells us the multi-channel electrical conductivity monitoring is of paramount consequence. It, however, is a rare event when this approach becomes routinely available in that commonly used commercial stand-alone type sensors are very expensive and inadequate for a long term monitoring of electrical conductivity or water level due to their restricted storage and difficulty of real-time control. For this reason, we have developed a real-time monitoring system that could meet these requirements. This system is user friendly, cost-effective, and easy to control measurement parameters - sampling interval, acquisition range, and others. And this devised system has been utilized for the electrical conductivity monitoring in boreholes, Yeonggwang-gun, Korea. Monitoring has been consecutively executed for 24 hours, and the responses of electrical conductivity at some channels have been regularly increased or decreased while pumping up water. It, with well logging data implemented before/after pumping water, verifies that electrical conductivity changes in the specified depths originate from fluid movements through sand layer or permeable fractured rock. Eventually, the multi-channel electrical conductivity monitoring system makes an effective key to secure groundwater resources in coastal areas.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.12
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• pp.1830-1841
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• 2012

We investigated the changes in microbial and physicochemical characteristics of the raw materials of Saengsk (brown rice, barley, carrot, potato, Angelica utilis Makino and kale) during storage after treatment with slightly acidic electrolyzed water (SAEW). To confirm the antimicrobial effects of the treatment washing solutions as well as the physicochemical changes in chromaticity, we stored the raw materials of Saengsik for 5, 10, 15, 20, 25 and 30 days at storage temperatures of 4, 10, 15, 20, 25 and $30^{\circ}C$ in a shelf-life study. The effects of microbial inhibition were higher in carrot treated with SAEW than in that treated with NaOCl, as indicated by a 1.75 log CFU/g reduction. Moreover, a 1.54 log CFU/g reduction of total coliforms was achieved in brown rice in response to SAEW treatment, which was higher than NaOCl treatment at all storage temperatures and periods. The lightness, redness and yellowness values of the raw materials of Saengsik were not significantly affected by SAEW treatments, except for Angelica utilis Makino and kale, whereas SAEW treatment resulted in decreased chromaticity values when compared to the NaOCl treatment. Overall, there was a significant difference (p<0.05) between the efficacy of the SAEW and NaOCl treatments. These results indicate that washing with SAEW is an effective method to reduce the microorganisms and enhance the shelf-life of raw materials of Saengsik; therefore, it can be effectively used to sanitize ingredients of Saengik without affecting the other properties during storage.

• Journal of Hydrogen and New Energy
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• v.35 no.1
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• pp.66-74
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• 2024

This study addresses the escalating issue of worldwide hydrogen gas accidents, which has seen a significant increase in occurrences. To comprehensively evaluate the risks associated with hydrogen, a two approach was employed in this study. Firstly, a qualitative risk assessment was conducted using the bow-tie method. Secondly, a quantitative consequence analysis was carried out utilizing the areal locations of hazardous atmospheres (ALOHA) model. The study applied this method to two incidents, the hydrogen explosion accident occurred at the Muskingum River power plant in Ohio, USA, 2007 and the hydrogen storage tank explosion accident occurred at the K Technopark water electrolysis system in Korea, 2019. The results of the risk assessments revealed critical issues such as deterioration of gas pipe, human errors in incident response and the omission of important gas cleaning facility. By analyzing the cause of accidents and assessing risks quantitatively, the effective accident response plans are proposed and the effectiveness is evaluated by comparing the effective distance obtained by ALOHA simulation. Notably, the implementation of these measures led to a significant 54.5% reduction in the risk degree of potential explosions compared to the existing risk levels.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.1
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• pp.28-34
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• 2020

A reservoir is defined as an artificial facility that stores and controls water during floods and droughts. Korea has constructed and managed reservoirs all over the country to benefit farming communities. The importance of reservoirs has decreased gradually due to urbanization and the spread of tap water, but the importance of water is increasing because of the recent shortage of water and the resulting rise in the price of water resources. Therefore, this study suggests countermeasures through an analysis of the used threshold for agricultural reservoirs. To this end, the forecast of rainfall up to 2100 was first analyzed using flood estimates and RCP scenarios through rainwater data collection. The increase in the RCP 8.5 scenario, the largest increase in the probability rainfall, was calculated by adding it to the current probability rainfall, and it was predicted that the marginal height of Odong Dam would reach its limit in 2028. Therefore, as a countermeasure against this, the measures to secure effective water storage were suggested through measures, such as lowering the height of Yeosu and installing movable beams. Overall, it is expected that effective management of the reservoirs used for agriculture will be possible in the future.

• Korean Journal of Weed Science
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• v.14 no.4
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• pp.252-257
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• 1994

The sprouting characteristics of Scirpus planiculmis and storage methods of corm for the herbicide screening were investigated under both laboratory and greenhouse conditions. Sprouting and elongation of S. planiculmis corms were continued during storage at low temperature ($5^{\circ}C$) and wet condition. However, sprouting of corm was failed when the surface water was removed from the corm, and elongation was reduced by the treatment of 0.5-1.0% sodium chloride(NaCl) solution. Alternate temperature was more effective on the sprouting of S. planiculmis corm than constant temperature. Optimum temperature for the sprouting of S. planiculmis corm was alternation between $25^{\circ}C$ to $35^{\circ}C$. Storage at $-20^{\circ}C$ for 10 min. or 14.7% dehydration made the corm of S. planiculmis to fail for sprouting. S. planiculmis corm was more tolerant to sodium chloride than Echinochloa crus-galli or Oryza sativa(Donginbyeo) seeds. Sprouting rate was decreased by cutting of the corm. Sprouting percent by vertical cuttings, horizontal cuttings, and vertical plus horizontal cuttings were 72, 56, and 28%, respectively.

• Food Science of Animal Resources
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• v.31 no.1
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• pp.122-128
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• 2011

This study was conducted to investigate the antioxidant effects, total plate count (TPC), and residual nitrite content of emulsified sausage with added mugwort during cold storage. The sausages were of five types: nothing added (control), mugwort powder added (T1), mugwort juice added (T2), mugwort ethanol extract added (T3), and mugwort hot water extract added (T4). Each sausage type was tested in triplicate and assigned to one of five storage periods: 0, 1, 2, 3, or 4 wk. As storage time increased, the presence of mugwort resulted in decreased pH, residual nitrite content, and meat color (CIE $L^*$ and $b^*$) and increased thiobarbituric acid reactive substance (TBARS) and TPC values. Values for pH, TBARS, residual nitrite, and TPC decreased significantly after adding mugwort compared with the control (p<0.05). Among all treatments, T3 was significantly (p<0.05) more effective in delaying lipid oxidation and microbial activity. The CIE $L^*$ and $b^*$ decreased significantly with the addition of mugwort relative to the control. In conclusion, the results demonstrate that adding an ethanol extract of mugwort (T3) to emulsified sausages tended to improve antioxidant and antimicrobial effects and residual nitrite content during storage compared to the other treatment groups.

• Food Science and Preservation
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• v.11 no.2
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• pp.170-174
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• 2004

Whole muskmelon was blanched at 50$^{\circ}C$ water for inhibition decline of fresh-cut melon quality from direct heat treatment. The muskmelon, after storage at 5$^{\circ}C$ for 24 hours, was processed to melon cylinders with 2 cm diameter. The changes of color, texture and the quality characteristics such as gas composition. soluble solid content, pH during storage at 5$^{\circ}C$ were measured. Degree of oxygen contents decreased and that of carbon dioxide in melon cylinder increased during storage. Especially, changes of gas composition inside packages appeared high level cor in blanched melon cylinders than non-treatment melons. Blanching with whole fruits at 50$^{\circ}C$ had effects on hardness in melon cylinder. Blanched melon, without regard on branching time, appeared higher hardness value than that of non-blanched melon at 6 days storage. There were slight difference between treatment on melon cylinder color. Degrees of change in soluble solid contents and pH on melon cylinder blanched at 50$^{\circ}C$ for 20minuets were lower than that of other treatments. In consequence, blanching with whole fruit at 50$^{\circ}C$ for 20minuets, before minimal processing, was effective in preserving of texture and quality of melon cylinder during storage.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.16 no.2
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• pp.243-260
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• 2018

A literature review on the effects of high temperature and radiation on radiation shielding concrete in Spent Fuel Dry Storage is presented in this study with a focus on concrete degradation. The general threshold is $95^{\circ}C$ for preventing long-term degradation from high temperature, and it is suggested that the temperature gradient should be less than $60^{\circ}C$ to avoid crack generation in concrete structures. The amount of damage depends on the characteristics of the concrete mixture, and increases with the temperature and exposure time. The tensile strength of concrete is more susceptible than the compressive strength to degradation due to high temperature. Nuclear heating from radiation can be neglected under an incident energy flux density of $10^{10}MeV{\cdot}cm^{-2}{\cdot}s^{-1}$. Neutron radiation of >$10^{19}n{\cdot}cm^{-2}$ or an integrated dose of gamma radiation exceeding $10^{10}$ rads can cause a reduction in the compressive and tensile strengths and the elastic moduli. When concrete is highly irradiated, changes in the mechanical properties are primarily caused by variation in water content resulting from high temperature, volume expansion, and crack generation. It is necessary to fully utilize previous research for effective technology development and licensing of a Korean dry storage system. This study can serve as important baseline data for developing domestic technology with regard to concrete casks of an SF (Spent Fuel) dry storage system.

• Analytical Science and Technology
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• v.36 no.3
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• pp.113-120
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• 2023

Physical developer (PD) is an effective technique that can develop fingerprints even on wet or very old paper. However, it has not been known which substance reacts with PD. Also, the timing of optimization according to the storage period of the PD working solution has not been known. The present research has done a spot test with 7 eccrine components and 5 sebaceous components that known as fingerprint components and figured out the mixture of palmitic acid and lysine gave the strongest positive reaction. Also, paper treated with PD was treated in 1,2-indanedione/zinc (1,2-IND/Zn) working solution and showed lysine was not dissolved in water. To find out the timing of optimization according to the storage period of the TWEEN^® 20 based PD working solution, the mixture of palmitic acid and lysine was used for the target of reagent reliability test. As the result, working solution of 14 days storage period showed better result than other working solutions.