• Journal of the Korean Institute of Gas
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• v.25 no.3
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• pp.27-38
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• 2021

We devised the system to automatically shutdown the boiler and to fundamentally block the harmful gases, including carbon monoxide, into the indoor when the exhaust system swerves: (1) The discharge pressure of the exhaust gas decreases when the exhaust pipe is disconnected. The monitoring system of the exhaust pipe is implemented by measuring the output voltage of APS(Air Pressure Sensor) installed to control the amount of combustion air. (2) The operating software was modified so that when the system recognizes the fault condition of a flue pipe, the boiler control unit displays the fault status on the indoor regulator while shutting down the boiler. In accordance with the ventilation facility standards in the "Rules for Building Equipment Standards" by the Ministry of Land, Infrastructure and Transport, experiments were conducted to ventilate indoor air. When carbon monoxide leaked in worst-case scenario, it was possible to prevent poisoning accidents. However, since 2013, the number of indoor air exchange times has been mitigated from 0.7 to 0.5 times per hour. We observed the concentration exceeding TWA 30 ppm occasionally and thus recommend to reinforce this criterion. In conclusion, if the flue pipe fault detection and the indoor air ventilation system are introduced, carbon monoxide poisoning accidents are expected to decrease significantly. Also when the manufacturing and inspection steps, the correct installation and repair are supplemented with the user's attention in missing flue, it will be served to prevent human casualties from carbon monoxide poisoning.

• Food Engineering Progress
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• v.13 no.1
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• pp.56-63
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• 2009

The aim of this study was to control the outbreak of food pathogen through quantitative microbial risk assessment (QMRA). We used Monte Calro Simulation (MCS) to predict contamination levels of Staphylococcus aureus on the raw materials, equipments and cook in Japanese restaurant located in Seoul. The result of sensitivity analysis showed that the most significant factor for the outbreak of food pathogen was consumption temperature and storage time. In shrimp and octopus sushi, 'consumption temperature' was the highest sensitivity value of 0.419 followed by 'storage time' of 0.374. To increase safety of sushi, consumers should have sushi as soon as possible after cooking. In sushi 'storage time after cooking' was determined as Critical Control Point (CCP). To determine Control Limit (CL), Scenario Analysis (SA) was carried out. In sushi, SA was carried out using storage time as a unit condition. Safety level of S. aureus was set lower than 5 log CFU/g. After 2 hr 'storage time' the number of S. aureus increased to 3.908 log CFU/g. Therefore, 'storage time' of sushi was set as CL in case of room temperature storage.

• Korean Journal of Breeding Science
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• v.42 no.6
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• pp.707-710
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• 2010

A new perilla cultivar, 'Bomnaeyeop 1 ho' was developed by, Kangwon National University in 2008. Its characteristics were investigated three times from 2006 to 2008 under optimal condition of cultivation. 'Bomnaeyeop 1 ho' can be characterized by dark green leaf color and tall plant height. This cultivar has more number of flower cluster and ear per cluster compare to 'Saeyeupsil' control. From result of GC/MS analysis, main compounds consist of perilla ketone, beta-caryophyllene and myristicin in 'Bomnaeyeop 1 ho' cultivar.

• Korean Journal of Breeding Science
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• v.42 no.1
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• pp.56-60
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• 2010

This study was carried out to develop of macro-protocol and the biosafety guide Golden Rice, modified vitamin A at large scale GMO field. Commercialization of genetically modified (GM) plants will be required the assessment of risks associated with the release of GM plants that should include a detailed risk assessment of their impacts in the environment and human health. Prior to GM plant release, applicants should provide the information on GM crops for approval. A total of $4,700m^2$ GM field, each of Golden Rice and 'Nakdong' were used for further analysis on agronomic traits and pathogenesis. Generally plant growth and panicle number in the transgenic lines were lower than in the wild type under field condition. The major agronomic traits such as plant growth, grain quality in Golden Rice were similar than in 'Nakdong'. The yield difference was due to reduced ripened rate and the 1,000 grain weight. The grain shape was similar donor plant, however, color of brown rice was different from segregation. Also the difference of pathogenesis reaction was not significant in the leaf blast and sheath blight between Golden Rice and 'Nakdong'. These results provided the agronomic data and pathogenesis for risk assessment analysis of Golden Rice and suggested that the macro-protocol could be useful to detect GM plants.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.4
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• pp.224-231
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• 2019

The current paper was conducted to unravel the influence of affect induction as a background emotion in the process of cognitive task to judge the degree of sequence in groups with or without anxiety symptoms. Four types of affect induction and two sequential task types were used as within-subject variables, and two types of college students groups classified under the Beck Anxiety Inventory (BAI) as a between-subject variable were selected to determine reaction times involving sequential judgment among the lexical relevance information. DmDx5 was used to present a series of stimuli and elicit a response from subjects. Repeated measured ANOVA analyses revealed that reaction times and error rates were significantly larger with anxiety participants compared to the normal group regardless of affect and task types. Within-subject variable effects found that specific affect type (sorrow condition) and number-related task type showed a more rapid response compared to other affect types and magnitude-related task type, respectively. In sum, these findings confirmed the difference in tendency with reaction time and error rates that varied as a function of accompanying affect types as well as anxiety level and task types suggesting the that underlying background affect plays a major role in processing affect-cognitive association tasks.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.64 no.1
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• pp.48-54
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• 2019

This research was carried out to investigate the plant growth, inorganic ion and amino acid content characteristics in a halophyte, Suaeda glauca, under different NaCl concentrations for cultivating in the reclaimed land. S. glauca was hydroponically cultivated under 0, 50, 100, 200, 300 and 400 mM NaCl concentrations with Hogland's nutrient solution. To evaluate growth response under different NaCl concentrations, plant height and number of branches, dry weight, Fv/Fm value, and photosynthetic efficiency were investigated. To find out physiological characteristic, inorganic ion contents and amino acids in the plant were evaluated. The optimum concentration of NaCl for plant growth were 50 mM. The plant growth were gradually decreased in the concentration ranged from 100 to 400 mM. As increasing of NaCl concentration, Na ion was increased, but K, Ca, Mg ions were decreased in the plant. The amino acid contents were varied due to NaCl concentrations, but most of amino acids content in total plant was the lowest at 50 mM. Conversely, proline was exceptionally high at 50 mM of NaCl concentration. The Fv/Fm value was the highest at 50 mM of NaCl concentration. From these results, the optimum salt concentration for the growth of S. glauca was 50 mM, but the plant seems to adapt in a variety of salt environments in view of the change of ions and amino acids depending on salt concentration and the maintenance of photosynthetic efficiency even under high salt condition.

• Clean Technology
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• v.25 no.2
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• pp.153-160
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• 2019

As air pollution becomes more serious due to the increased number of diesel vessel operations, ship regulations on harmful emissions strengthen. Therefore, the development of a diesel exhaust after-treatment system for ships is required, and the higher the flow uniformity of the exhaust treatment system, the higher the treatment efficiency. With the computer software ANSYS Fluent, pressure drop and flow uniformity were used in this study to simulate flow rate with and without a baffle in both a Diesel Oxidation Catalyst (DOC) and Diesel Particulate Filter (DPF) system. The system pressure drop was found to be 38 to 40 mbar in the existing system condition, and the flow uniformity was approximately 84 to 92% at the inlet and outlet of the DOC. When the baffle was installed inside the system, the pressure increased and the flow uniformity was lowered due to an increase in flow rate. When the exhaust gas flow was reduced by 50% from $7,548kg\;h^{-1}$ to $3,772kg\;h^{-1}$, the flow uniformity at the inlet and outlet of the DOC increased by approximately 1 to 3% due to the low flow rate. In the case of DPF, the flow uniformity of exhaust gas was 98 to 99% because the uneven flow proceeded after uniformly flowing from the DOC.

• Journal of Korea Water Resources Association
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• v.52 no.6
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• pp.381-395
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• 2019

The purpose of this study is to predict agricultural reservoir storage rate (RSR) in a month. This algorithm was developed by multiple linear regression model (MLRM) which included the past 3 months RSRs data and the future climate change scenarios. In order to improve use of predicted RSR, this study need the severe criteria in terms of drought. So, the predicted RSR was indexed as the 3 months reservoir drought index (RDI3) and then it was disaggregated into drought duration, severity, and intensity. For the future RSR estimation by climate change scenarios, the 6 RCP 8.5 scenarios of HadGEM2-ES, CESM1-BGC, MPI-ESM-MR, INM-CM4, FGOALS-s2, and HadGEM3-RA were used in three future evaluation periods (S1: 2011~2040, S2: 2041~2070, S3: 2071~2099). The future S3 period of HadGEM2-ES scenario which has the biggest increase in precipitation and temperature showed the largest decrease to 60.2% among the 6 scenarios compared to the historical RSR (1976~2005) 77.3%. In contrast, INM-CM4 scenario which has smallest changes in precipitation and temperature in S3 period showed the smallest decrease to 72.8%. For the CESM1-BGC and MPI-ESM-MR, FGOALS-s2, and HadGEM3-RA, the S3 period RSR showed 72.6%, 72.6%, 67.4%, and 64.5% decrease respectively. The future severe drought condition of RDI3 below -0.25 showed the increase trend for the number and severity up to -2.0 during S3 period.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.6
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• pp.278-287
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• 2019

This study was conducted to identify the predictors influencing fear of falling in community-dewelling elderly. A secondary data analysis was performed using data of 65 years or older elderly who participating in the 2014 Korean Elderly Survey(Jun. 11th ~ Sep. 4th 2014). Multivariated logistic regression analysis was used to identify the risk factors of fear of falling. 81.5% of the elderly had fear of falling. There were significant factors, sex(OR=2.87, p<.001), education(OR=1.73, p<.001), presence of cohabiting spouse(OR=1.19, p<.001), experience of falling(OR=6.35, p<.001), arthritis(OR=1.83, p<.001), depression(OR=2.25, p<.001), cognitive deficit (OR=1.24, p<.001), instrumental activities of daily living (OR=1.98, p<.001), exercise(OR=1.29, p<.001) and the number of chronic diseases(over 3: OR=2.53, p<.001, 1~2: OR=1.73, p<.001), predicting fear of falling in community-dwelling elderly. Fear of falling was associated with multifactorial condition, and arthritis was an important factor in chronic disease. This study will provide fundamental information on programming and a policy proposal related to fear of falling.

• Journal of the Korean Society of Food Culture
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• v.34 no.2
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• pp.217-223
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• 2019

This study aimed to evaluate the characteristic differential between whole cabbage kimchi (pogi kimchi) and sliced cabbage kimchi (mat kimchi) during kimchi fermentation at $6^{\circ}C$. The difference of microbial and physicochemical properties was investigated until 6 weeks. For the changes in the microbial flora, both kimchi samples exhibited a continuous increase in total aerobic bacteria and lactic acid bacteria (LAB) population size up to 2 weeks followed by a stationary phase until 5 weeks. Interestingly, the number of LAB of mat kimchi was overall higher than that of pogi kimchi during kimchi fermentation. We speculate that mat kimchi has in a more advantageous growth condition than pogi kimchi for microbial growth because small kimchi cabbage size appropriately derives nutritional supply in order to increase the LAB growth. During lactic fermentation at $6^{\circ}C$, physicochemical changes in the pH, salinity, and titratable acidity was observed to be no significant differences between two types of kimchi. Furthermore the contents of organic acids such as oxalic acid, citric acid, malic acid, lactic acid, fumaric acid, and acetic acid was not significantly different (p>0.05) between both kimchi samples as well as the contents of total free amino acid.