• Journal of the Korean Wood Science and Technology
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• v.46 no.1
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• pp.48-59
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• 2018

This study was conducted to suggest the effective management and recycling processes of coffee waste, which can be easily obtained from coffee shops and coffee-related products industries. Prior to the fabrication of pellets, the potential of coffee waste as a raw material of pellet was investigated through the examination of its chemical compositions and fuel characteristics. Major gradient included in coffee waste was holocellulose, followed by fat/oil and protein. Coffee waste contained a small quantity of ash (0.7%), such as calcium, sodium, potassium and magnesium. Interestingly, coffee waste was easily dried probably due to its porous structure. Pellets fabricated with coffee waste and larch sawdust showed good fuel characteristics, such as moisture content, ash content, density and durability. The pellets exceed greatly the minimum requirements of $1^{st}$-grade wood pellet standard designated by National Institute of Forest Science (NIFOS). Particularly, the high calorific value of coffee waste showed the potential as a raw material of pellet. However, owing to high nitrogen and sulfur contents, coffee waste is like to be used as a raw material of wood pellet for combined heat and power plants equipped with a reduction system of $NO_x$ and $SO_x$ gases. On the other hand, 91 wt% larch sawdust and 9 wt% coffee waste are required to fabricate the $1^{st}$-grade wood pellets designated by NIFOS. Pellets fabricated with the conditions are estimated to have nitrogen content of 0.298% and sulfur content of 0.03%. Lastly, if amounts of coffee waste and sawdust in the production of wood pellets are adequately adjusted according to its purchasing price, the manufacturing cost of pellet can effectively be reduced. In addition, it is expected tp prepare the effective recycling process of waste and to relieve the environmental burden with the reduction of waste from the commercialization of coffee waste/larch pellets.

• Journal of the Korean Association of Geographic Information Studies
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• v.22 no.4
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• pp.116-130
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• 2019

In South Korea, forest fire occurrences are increasing in size and duration due to various factors such as the increase in fuel materials and frequent drying conditions in forests. Therefore, it is necessary to minimize the damage caused by forest fires by appropriately providing the probability of forest fire risk. The purpose of this study is to improve the Daily Weather Index(DWI) provided by the current forest fire forecasting system in South Korea. A new Fire Risk Index(FRI) is proposed in this study, which is provided in a 5km grid through the synergistic use of numerical weather forecast data, satellite-based drought indices, and forest fire-prone areas. The FRI is calculated based on the product of the Fine Fuel Moisture Code(FFMC) optimized for Korea, an integrated drought index, and spatio-temporal weighting approaches. In order to improve the temporal accuracy of forest fire risk, monthly weights were applied based on the forest fire occurrences by month. Similarly, spatial weights were applied using the forest fire density information to improve the spatial accuracy of forest fire risk. In the time series analysis of the number of monthly forest fires and the FRI, the relationship between the two were well simulated. In addition, it was possible to provide more spatially detailed information on forest fire risk when using FRI in the 5km grid than DWI based on administrative units. The research findings from this study can help make appropriate decisions before and after forest fire occurrences.

• Korean Journal of Agricultural Science
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• v.2 no.2
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• pp.433-444
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• 1975

This study was conducted to investigate the strength of lime soil mixtures for varied' curing temperatures(20, 30, 40, 50, $60^{\circ}C$) and lime content (3, 6, 9, 12%) in four lime-stabilized soils(KY : Sand, MH : Sand, SS: Sandy loam. JJ : Loam). The experimental results obtained from unconfined compressive strength tests are as follows; 1. The optimum moisture content increased and maximum dry density decreased with the increase of the lime content. 2. The lime content for the maximum strength of SS and JJ soils showed at the 9 percent lime content, but KY and MH soils didn't show the tendency of increase and decrease by the lime content and curing period. The rate of decrease of the soaked unconfined compressive strength showed the lower value in accordance with lime content. 3. According to increase in curing temperatures in curing temperatures at 30, 40, 50, $60^{\circ}C$, the unconfined compressive strength of lime soil mixtures increased, the rate of increase initially increased at a rapid rate, and showed that around 120 hours were sufficient curing time to complete hardening. 4. The average maximum temperature of Korea being around $30^{\circ}C$ from July to August, thus these months are ideal construction periods to increase the strehgth of lime soil mixtures. 5. Accelerated curing times equivalent to 28-day normal curing decreased in accordance with the increase of curing temperature, and showed shorter in lime soil mixtures than soil cement. 6. Accelerated curing times versus normal curing times are formed as a linear, its slope decreased in accordance with the increase of curing temperature, it may be expressed as follows: (1). $30^{\circ}C$ : t=2.63d-1.4(r=0.99) (2). $40^{\circ}C$ : t= 1.76d-0.8(r=0.97) (3). $50^{\circ}C$ : t=1.35d-3.2(r=0.94) (4). $60^{\circ}C$ : t=0.49d+1.8(r=0.91) in which t ; Accelerated curing time d ; Normal curing time.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.10
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• pp.1294-1300
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• 2008

Nelumbo nucifera G. tea white breads were prepared by the addition of 0.01, 0.02, 0.03, and 0.04% hemicellulase to flour of the basic formulation. The experiments and control were then compared in terms of quality characteristics, including pH, total titratable acidity, fermentation power of dough expansion, specific volume, baking loss, moisture content, color, textural characteristics, external and internal surface appearances, and sensory qualities in order to determine the optimal ratio of hemicellulase in the formulation. There were no significant differences in pH and total titratable acidity of dough among the experiments. Fermentation power of dough expansion were increased as incubation time increased. Baking loss was the highest at the 0.04% addition level, while the lowest at the 0.01% level. As hemicellulase content increased, pH, hardness, and fracturability of bread decreased, while total titratable acidity, specific volume, and resilience increased. Water content and lightness were the highest in the control bread samples, and yellowness was maximal in the 0.01% group. Bread made by the addition of hemicellulase had significantly higher greenness and flavor than the control group. Color, consistency, and springiness of crumb, density and uniformity of crumb pore, softness, chewiness, overall acceptability, lotus leaf flavor, delicious taste, astringency, bitterness, and off-flavor were not significantly different among the samples. The results indicate that adding 0.02$\sim$ 0.03% hemicellulase in N elumbo nucifera G. tea white bread is optimal for quality and provides a product with reasonably high overall acceptability.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.23 no.3
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• pp.143-150
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• 2017

Effects of packaging methods for maintaining the shelf-life and postharvest quality of Korean chive (Allium tuberosum Rotter) usually called buchu in Korea was studied during fall season. Buchu, which has high moisture content and active metabolism after harvest, is characterized by the greater changes in quality during storage and distribution. It is usually packaged in paper box during distribution in domestic channel in Korea where the marketability ends within few days of harvest. In order to maintain the commercial quality of buchu, we tried to use inner film with or without absorbent paper in commercial paper box packaging. The 'Greenbelt' cultivar of buchu was harvested in october and packaged in corrugated paper box (A), in corrugated paper box with micro-perforated high density polyethylene (HDPE) film as inner material (B), a layer of absorbent paper both at the bottom and top of buchu in corrugated paper box (C) and a combination of HDPE film as inner material along with a layer of absorbent paper both at the bottom and top of buchu in corrugated paper box (D), and stored at $5^{\circ}C$ for up to 21 days. Several quality parameters such as fresh weight loss, respiration rate, color, chlorophyll content and sensory qualities were monitored during storage. When buchu was packaged only in paper box, the appearance and quality deteriorated rapidly through decay development thereby sample became unmarketable within 12 days. On the other hand, buchu packaged with inner HDPE film maintained its quality, good visual appearance and exhibited a longer period of marketable life compared to the samples stored in other treatments. However, the use of absorbent paper did not have any significant effect in maintaining quality of buchu. The uses of inner HDPE film was effective in reducing weight loss that resulted better visual appearance of buchu. Results suggest that the use of inner HDPE film in bulk type corrugated paper box packaging and storing at $5^{\circ}C$ could be the optimum condition for commercial storage of buchu. Further investigation on other quality parameters and packaging methods would be useful in maintaining the quality aspects of buchu at postharvest stages.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.62 no.3
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• pp.233-240
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• 2017

This experiment was conducted to establish a cultivation system for sorghum in reclaimed soils. Pot experiments were used to test the effects on seedling establishment of sowing depth, soil water content, and soil salinity using seeds of Nampungchal-susu and Hwanggeumchal-susu in reclaimed soil. Field experiments were also conducted to examine differences in growth characteristics and yield production, by sowing time, and planting distance. The result of the pot experiment, examining seedling establishment at various sowing depths revealed that, it was the highest 76.7% when the seeds were sown at a depth of 3 cm. Seedling establishment did not differ with soil water content between 10~30 kpa and at 51~70 kpa. No effects of seed moisture absorption before sowing were observed. Seedling establishment showed no differences with soil salinity below $3.2\;dS\;m^{-1}$, but decreased with Salinity above $4.8\;dS\;m^{-1}$. In field experiments to assess the effects on seedling establishment ratio of sowing time, Nampungchal-susu was revealed to have a high seedling establishment ratio following sowing on June 15. Hwanggeumchal-susu did not exhibits effects of sowing time, on seedling establishment ratio but exhibited higher seedling establishment when in low soil salinity conditions than when sown in high soil salinity conditions. With respect to yield, the yield of the seeds sown on June 15 was higher by 13% for Nampungchal-susu and by 29% for the Hwanggeumchal-susu than that those sown on June 25. With respect to soil salinity, the yield at a soil salinity of $3.2dS\;m^{-1}$ was lower by 23% than that at $1.6dS\;m^{-1}$ or lower for Nampungchal-susu, and was lower by 30% Hwanggeumchal-susu. With respect to planting density, both breeds showed the highest yield at $60{\times}10cm$. These results suggest that a sowing time of June 15 and a seeding distance of $60{\times}10cm$ are appropriate for sorghum in reclaimed land.

• Journal of Korean Society of Forest Science
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• v.89 no.3
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• pp.323-334
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• 2000

This study was carried out to investigate the effects of geological and topographical features on landslide and land-creep at the twenty four surveyed sites of Kyungpook province. According to the results obtained, it was concluded that continuous heavy rainfall was one of the primary factors to occur landslide and land-creep. Most of the landslides occurred in the past were concentrated in the granite and granitic gneiss zones, while land-creeps were mainly occurred in the mud-stone zones. Therefore, it was thought that the physical properties such as soil texture, solid phase, moisture contents, density, hardness and porosity rate of weathered granite and granitic gneiss could affect the occurrence of landslide and land-creep. Due to the holding of sand contents in the upper soil layers of weathered granite and granitic gneiss, rainfall could infiltrate into the soil easily. While lower soil layers contained much quantity of clay and silt contents, those soils saturated with rainfall cause to lose viscosity and shear strength. Therefore, it was seemed that landslide was occurred more easily and the saturation of those soils was made much easily by bed rocks under those soils. Landslide and land-creep are slided into lower place by gravitation and slope degree factors. Therefore, prediction of landslide occurrence is very difficult because landslide is occurred abruptly, and physical properties of the soil have to be understood and checking the existence of bed rocks under the soils is not easy, on the other hand, land-creep is progressed very slowly. Therefore, it was suggested that in a degree creeping could be protected by removing of several causing factors.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.9
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• pp.1439-1445
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• 2013

The aim of this study was to investigate the quality characteristics of rice cookies specifically prepared with rice flour following enzyme treatment. In this study, three types of specific enzyme treatments, that is, ${\alpha}$-amylase, ${\beta}$-amylase, and cellulose+${\beta}$-glucanase were applied on the effect of rice flour with respect to desired quality characteristics of the rice cookies. Based on our study results, we have found that the density of dough in the rice cookies was not significantly different between that of the non-enzyme treated (control) and the enzyme treated group. However, we found that the spread factor of rice cookies, prepared with rice flour treated with ${\beta}$-amylase, was higher than that of the control. It was also found that the moisture content of rice cookies (with added enzyme-treated rice flour) was 3.20 to 3.90%; however, this range is much lower than that observed in the control. Further, we observed that Hunter color's L-values were significantly higher for the control than those of the enzyme-treated cookies. We also found that hardness of enzyme-treated cookies was comparatively better than that of the control. In addition, the sensory acceptability scores of the enzyme-treated cookies were found to be significantly higher than the control in decisive parameters such as aroma, appearance, flavor, taste, texture, and overall acceptability. Based on our findings, we suggest that ${\alpha}$-amylase treated rice flour is an effective ingredient for improving the overall quality of rice cookies.

• Korean journal of food and cookery science
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• v.29 no.1
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• pp.11-18
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• 2013

In this study, rice wine cakes (Jubak) was produced using with Astragali memvranaceus with excellent antioxidant and antidiabetic effects and produced. This Jubak was applied to improve the cookies of modern taste and well-being products. The cookies according to the different ratio (added 0-1.0%) of Astragali memvranaceus and investigated the physicochemical characteristics, sensory evaluation, DPPH free radical scavenging activities, polyphenol and flavonoid contents. There were little changes in pH and density. The hardness of all treated cookies increased with Astragali memvranaceus Jubak(AJ) containing of different moisture contents. In color, L and a values of most cases increased in most of the treatments, but b value was reduced. In the sensory evaluation, the flavor and total scores showed the highest in 0.5% AJ cookies. But the higher proportion of AJ cookies that had unique flavors and tastes, so the total acceptance score decreased. The polyphenol and flavonoid contents increased in the higher proportion of AJ. In DPPH free radical scavenging activities, the control (no Jubak added) was 44%, and containing of 1% AJ cookies showed 82%. In conclusion, our study suggests that 0.5% in addition of AJ increased positive attributes and functional to cookies.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.6
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• pp.912-920
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• 2015

The study was designed to investigate the effects of die temperature and $CO_2$ injection on the physical and antioxidant properties of extruded rice with tomato flour. Moisture content and screw speed were fixed at 25% and 150 rpm, respectively. Die temperatures and $CO_2$ injection were adjusted to 80, 110, and $140^{\circ}C$ and 0, and 300 mL/min, respectively. Specific mechanical energy input decreased as die temperature increased from 80 to $140^{\circ}C$. The expansion index increased, while bulk density decreased with $CO_2$ injection. All extrudates showed increased water soluble index (WSI) and water absorption index through the extrusion process. WSI increased as die temperature increased. 1,1-Diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activity and total phenolic compounds increased as die temperature increased from 80 to $140^{\circ}C$. Total carotenoid and lycopene contents decreased through the extrusion process. Total carotenoid and lycopene contents upon 0 mL/min $CO_2$ injection and $140^{\circ}C$ die temperature were highest at $6.65{\mu}g/g$ and 2.69 mg/kg, respectively. In conclusion, $CO_2$ injection affects expansion properties while an increased die temperature leads to increased DPPH radical scavenging activity and total phenols.