• Korean Journal of Environmental Biology
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• v.38 no.3
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• pp.371-387
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• 2020

This study was conducted to investigate the flora of Mt. Unbongsan in the basalt areas of Korea. From the results of eight field surveys undertaken from March to October 2017, we identified 404 total taxa, representing 364 species, seven subspecies, and 33 varieties, which were placed in 256 genera and 91 families. The plant formation of Mt. Unbongsan is a deciduous broad-leaved and conifer mixed forest, which is common in the middle part of the Korean peninsula. Most of the mountain is covered by a young secondary forest, which is mainly composed of Quercus monglica and Pinus densiflora. Out of these 404 taxa, 193 were the first records for the region, six were endemic to Korea, three were listed on the Korean Red List of threatened species, 34 were floristic target species, and 40 were invasive alien species. The naturalized index(NI) percentage was 9.9%. Mt. Unbongsan has plant diversity, which was associated with the geomorphological landscapes. We considered that the composition and distribution of the species were affected by different environmental factors according to the presence of granite, taluses, block streams, drying ridges, valleys, puddles, wetlands, and streams.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.8
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• pp.1315-1324
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• 2018

Objective: An experiment was conducted to investigate the effects of different diet formulations: F1 (Two complicated basal diets containing different crude protein levels plus tested feedstuff) vs F2 (A simple corn soybean meal [SBM] basal diet plus tested feedstuff) combined with total collection (TC) or chromic oxide ($Cr_2O_3$) marker or acid-insoluble ash (AIA) marker method, and freeze-dry or oven-dry (OD) technique on estimation of nutrient digestibility in diets fed to growing pigs. Methods: In F1, twelve barrows were allocated to two $6{\times}4$ Youden Squares. The treatment diets included a high protein basal (HPB) diet, a low protein basal (LPB) diet, a corn diet and a wheat bran (WB) diet formulated based on the HPB diet, and a SBM diet and a rapeseed meal (RSM) diet formulated based on the LPB diet. In F2, eight barrows were allocated to two $4{\times}4$ Latin Squares. The treatment diets included a corn basal diet, a SBM basal diet formulated based on the corn diet, and a WB diet and a RSM diet formulated based on the SBM diet. Results: Concentration of digestible (DE) and metabolizable energy (ME), and the apparent total tract digestibility of gross energy, ash, neutral detergent fibre, and acid detergent fibre determined by $Cr_2O_3$ marker method were greater than those determined by TC and AIA marker methods in HPB, LPB, and RSM diets formulated by F1 and in corn diet formulated by F2 (p<0.05). The DE values in WB and both DE and ME values in SBM and RSM estimated using F1 were greater than those estimated using F2 (p<0.05). Conclusion: From the accuracy aspect, the AIA marker or TC method combined with OD technique is recommended for determining the energy concentration and nutrient digestibility of components in diets fed to growing pigs.

• Food Science and Preservation
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• v.22 no.3
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• pp.385-391
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• 2015

This study was conducted to develop a spray-dried garlic chives (Allium tuberosum) powder and to evaluate its quality characteristics depending on the treatment of steam blanching pretreatment $100^{\circ}C$, 3 min) and the addition of forming agents (dextrin (DE=10), ${\beta}$-cyclodextrin) during process. The steam blanching pretreatment showed an increase in $L^*$ value while a decrease in $-a^*$, $b^*$, $C^*$, and $h^o$ values of the powder. Moisture content and water soluble index were not affected by the treatment of steam blanching and the addition of forming agents, whereas the particle diameter was the smallest in the steam blanching treatment and dextrin addition. Chlorophyll, phenolic compound, and vitamin C content, and DPPH radical scavenging activity of non-pretreated powder were significantly higher than those of the steam blanching treated powders. However, there was no significant difference between the two forming agents. The sensory acceptability (color, smell, and overall acceptability) of powder treated with steam blanching were significantly higher than those of non-pretreated powders. Therefore, the steam blanching pretreatment of fresh garlic chives affected on the better quality characteristics of the spray-dried powders when compared with non-pretreated powder though it adversely affected the natural chemical quality of fresh garlic chives.

• Food Science of Animal Resources
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• v.35 no.5
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• pp.622-629
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• 2015

The objective of this study was to investigate the effects of replacing sucrose with sugar alcohols (sorbitol, glycerol and xylitol) on the quality properties of semi-dried jerky. Total 7 treatments of jerkies were prepared as follows: control with sucrose, and treatments with 2.5 and 5.0% of sucrose replaced by each sugar alcohol, respectively. Drying yield, pH, water activity, moisture content, shear force, myofibrillar fragmentation index (MFI), 2-thiobarbituric acid reactive substance (TBARS) value, sugar content, and sensory evaluation were evaluated. Xylitol slightly decreased the pH when compared to the other sugar alcohols (p>0.05). The water activity of the semi-dried jerky was significantly reduced by treatment with glycerol and xylitol (p<0.05). The moisture content of semi-dried jerky containing various sugar alcohols was significantly higher than that of the control (p<0.05), while replacing sucrose with glycerol yielded the highest moisture content. The shear force of semi-dried jerky containing sugar alcohols was not significantly different for the sorbitol and glycerol treatments, but that replacing sucrose with 5.0% xylitol demonstrated the lowest shear force (p<0.05). The TBARS values of semi-dried jerkies with sugar alcohols were lower than the control (p<0.05). The sugar content of the semi-dried jerkies containing sorbitol and glycerol were lower than the control and xylitol treatment (p<0.05). In comparison with the control, the 5.0% xylitol treatment was found to be significantly different in the sensory evaluation (p<0.05). In conclusion, semi-dried jerky made by replacement with sugar alcohols improved the quality characteristics, while xylitol has applicability in manufacturing meat products.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.3
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• pp.342-347
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• 2008

This study was to develop processed food with the addition of onion powder by investigating the quality characteristics of cookies with various levels (0, 1, 3, 5 and 10%) of hot-air dried yellow and red onion powder. Moisture (11.59%), crude protein (4.56%), and crude ash contents (3.83%) of yellow onion powder showed higher value than red onion powder. Hot-air dried yellow onion powder showed a higher L and b value as compared with red onion powder because of the unique color of the onion. Browning index was lower in red onion powder than red onion powder. Phenolic contents of yellow onion powder appeared to be higher than that of red onion powder. Total sugar contents were higher in red onion powder than yellow onion powder. The pH of the dough significantly decreased with increase of added onion powder contents. Dough density of control had a significantly higher value than the other samples. Hardness measurement showed significantly higher value with increasing additions of onion powder contents; added red onion powder samples were the most highest when compared to added yellow onion powder samples. Results of sensory characteristics showed significantly higher smell, taste, texture and overall acceptability with 3% added red onion sample. Quality characteristics of 5% added yellow onion powder sample and 3% added red onion powder sample indicated possibilities for developments of onion cookies.

• Journal of Ginseng Research
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• v.31 no.4
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• pp.222-229
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• 2007

Changes on physicochemical properties of fresh Korean ginseng during repeated 9 times steaming processes, steaming $90{\sim}95^{\circ}C$ for $1{\sim}3\;hr$ followed by hot air-drying at $50^{\circ}C$ for $36{\sim}48\;hr$, were investigated. The water contents decreased from 73.4% of fresh ginseng to 13.7% finally. The final yields in bases of total weights and dry matter were 21.0% and 79.0%, respectively. As the times of steaming processes increased, lightness (L value) decreased and redness (a value) increased in color of ginseng powder. Browning index also rapidly increased after 3 times of steaming process in particular. Total water soluble sugar contents decreased from 55.4% in fresh to 38.6% in final processed ginseng, but acidic polysaccharide contents increased by about 50% with increasing times of steaming process. Total phenolic compound contents significantly increased with repeated steaming processes especially after 5 times of steaming processes and crude saponin contents also increased in some degree. In the case of major ginsenosides, the contents of $Rb_1$, $Rb_2$, $Rg_1$, Re (representative ginsenosides in fresh ginseng) decreased, but those of $Rg_2$, $Rh_1$, $Rg_3$ (unique ginsenosides in red ginseng) increased after especially 5 times of steaming processes.

• Journal of Korea Water Resources Association
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• v.54 no.11
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• pp.999-1009
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• 2021

As the frequency and intensity of extreme weather events due to climate change are increasing in recent years, it is very important to evaluate and analyze climate conditions to manage and respond to the negative effects of climate change in advance. In this study, the trends and characteristics of regional climate change were analyzed by calculating the climate indices for the Chungcheong Province. Annual and monthly UNEP-MP, UNEP-PM and MDM indices were calculated using daily data from 1973-2020 collected from 10 synoptic meteorological stations operated by the Korea Meteorological Administration. The normality of climate data was analyzed through the KS test, and the climate change trend was analyzed by applying the Spearman and Pearson methods. The Chungcheongnam-do region had a relatively humid climate than the Chungcheongbuk-do region, and the annual climate indices showed a dry climate trend in Cheongju and Chungju, while the climate of Seosan and Buyeo was becoming humid. Based on the monthly trend change analysis, a humid climate trend was observed in summer and autumn, while a dry climate trend was observed in spring and winter. Comparison of climate indices during the past (2001-2010) and the recent (2011-2020) years showed a higher decrease in the average climate indices during the last 10 years and a gradually drying climate change trend was recorded.

• Journal of the Korean Society of Safety
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• v.38 no.4
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• pp.39-46
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• 2023

Pine trees, which account for 23% of the forested area of the Republic of Korea, are highly vulnerable to fire in comparison to broad-leaved trees due to the presence of consistent water tube sections throughout the year and resin that is composed of approximately 20% oil. In addition, the pattern of forest fires is determined by weather, topographic conditions, and fluctuation in moisture content. Therefore, when fire breaks out in pine tree forests during the dry season (January to March), it is difficult to extinguish, and it quickly spreads. In this study, the combustion characteristics of pine needles, pine cones, and pine branches in the water tube sections of living pine trees were compared and analyzed in accordance with the moisture content as per the ISO 5660-1. The monthly moisture content was analyzed from January to March, and it was found to be the lowest in March, with 53.6% for pine needles, 51.9% for pine branches, and 10.9% for pine cones. In particular, pine cones were more vulnerable to fire as compared to pine needles and pine branches because their moisture content was more than five times lower than that of pine needles and branches. The ignition time, which affects the speed of flame propagation, was the most rapid in March, and the fastest ignition time was for pine cones, at 19 seconds, followed by 34 seconds for pine needles, and 256 seconds for pine branches. The pine branches were the last to be ignited due to the effect of density, according to the thickness and specific gravity of the specimen. The peak heat release rate, which is a measurable index of fire intensity, was analyzed for pine cones and found to be 184.28 kW/m² , while the mean effective heat of combustion was 19.79 MJ/kg, and the total heat release rate was 39.7 MJ/m² , and these values were higher than those of pine branches and pine needles. Thus, we determined that the flame propagation speed and fire intensity according to the moisture content can be used to evaluate the risk of fire to the water tube section of pine trees. It is suggested that because of the combustion characteristics of the pine cone in March, that is when the forest is most vulnerable to fires.

• Clean Technology
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• v.16 no.3
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• pp.172-181
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• 2010

Hydrofluoroethers (HFEs) with fluoride molecules in their structure which are evaluated as the third generation replacement alternatives to chlorofluorocarbons (CFCs) are known to be excellent for removal of nanoparticles and fluoride-type soils due to their low surface tension and high wetting index. In addition, HFEs have good physical properties with no flash point and excellent drying characteristics. But, HFEs also have shortcomings in that they are not effective for removal of organic soils due to their poor solubility in soil. In this study, $C_5$ HFE-based cleaning agents were formulated through addition of solvents such as isopropyl alcohol (IPA), ethyleneglycol monoether (EG), propyleneglycol monoethylether (PM) to HFE-7100 [$CF_3CF_2CF_2CF_2OCH_3$] or HFE-mec-f [$CF_3CHF=CF_2OCH_2CF_3$] with its maximum amount, respectively, in order to have no flash point for the safety in the working environment. These solvents are known to be excellent for dissolving organics in soil. Their physical properties and cleaning abilities for fluxes, water-insoluble cutting oils, and fluoride-type oils were evaluated and compared with those of other cleaning agents with single components. The experimental results show that the HFE-based formulated cleaning agents have various good physical properties which are almost similar to those of a single type of HFE cleaner. They show excellent cleaning ability for fluxes, water-insoluble cutting oils, and fluoride-type oils. These results indicate that the HFE-based formulated cleaning agents can be applicable to various industrial cleaning fields because of their good physical properties and cleaning abilities for various soils.

• Food Science and Preservation
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• v.30 no.6
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• pp.983-990
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• 2023

This study was conducted to develop a preservation technology that can induce changes in physicochemical properties to effectively utilize of persimmon leaves. The application effects of steaming or freezing technique were investigated. Astringent persimmon leaves were steam-blanched (100℃, 30 sec) or frozen (-20℃, 15 d), followed by hot-air drying (50℃). The physicochemical properties of the extract obtained by hot-water leaching from the dried leaves were compared. The extract of leaves dried without pretreatment was used as a control. L* value was higher in steamed than in control and frozen. a* value was highest in the control. The browning index was higher in the frozen and lower in the steamed than in the control. Soluble solids were the highest in the steamed and the lowest in the frozen. Sucrose content was relatively high in the steamed, and the glucose and fructose contents were relatively high in the frozen. Total polyphenol content and DPPH radical scavenging activity were higher in steamed and lower in frozen than in control. Thus, it was confirmed that steam or freeze pretreatment after harvesting persimmon leaves affects the extraction yield, color, antioxidant capacity and component changes of dried persimmon leaves. Unlike steaming, freezing pretreatment showed the effect of promoting decomposition and browning reactions, and it is considered useful when such an effect is needed.