• Journal of the Korean Recycled Construction Resources Institute
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• v.3 no.4
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• pp.328-334
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• 2015

Building insulation materials use for the purpose of energy saving. Insulation materials can be classified inorganic and organic insulation materials. Inorganic insulation is used for fire resistive performance parts and organic insulation is used for thermal performance parts. Meanwhile, organic insulation is due to toxic gas emission in fire. Inorganic insulation is too heavy and low thermal performance than organic materials. This study is focused on evaluation of the physical properties of inorganic foam material using industrial by-products such as waste glass powder and fly ash. From the test result, inorganic foam materials for the applicability of fire-resistance and insulation light-weight materials.

• Journal of the Korea institute for structural maintenance and inspection
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• v.19 no.5
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• pp.22-29
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• 2015

Modern structures is the tendency of being increasingly taller and larger. The concrete with large weight has the disadvantage of increasing the weight on the structure. therefore, the method of carrying out the weight saving of the concrete is required. one of such method is to use a lightweight aggregate. However, studies on structural lightweight concrete, lacking for the recognition of the lightweight concrete, so also is lacking. therefore it is necessary to study on the physical characteristic value of the lightweight concrete. In this study, in order to investigate the tensile properties of lightweight concrete, Crack mouth opening displacement (CMOD) experiments were carried out. the fracture energy of the lightweight concrete subjected to inverse analysis were derived from the CMOD experimental results.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.55 no.1
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• pp.70-75
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• 2010

In Korea, standard N application level was amended from 110 to 90kg per ha for high quality rice production in 2005. So far, N application method, however, has not been considered for yield and quality based on changed standard N application level. Therefore, this experiment was conducted to find out more efficient N application method for improving rice quality or labor saving under the amended standard N application level with several varieties at three site (Suwon, Iksan, and Milyang) for two years from 2005 to 2006. Top dressing of N at 15 days before heading compared to the standard (25 days before heading) showed improved rice qualities such as 1000 grain weight and head rice ratio without changing rice yield and protein content of brown rice. In addition, there were no significant differences in yield and quality between different N split application of 70-0-30% and 50-30-20%, indicating that the former would be useful for labor saving without yield decrease and quality deterioration.

• Journal of Bio-Environment Control
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• v.25 no.3
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• pp.139-145
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• 2016

The objective of this study was to compare the growth and light use efficiency of red leaf lettuce grown under three types of combined light-emitting diodes (LEDs) and fluorescent lamps (FL) in a closed-type plant production system. The eighteen days-old lettuce seedlings of red leaf lettuce (Lactuca sativa L., 'Jeokchima') were transplanted to the close-type plant production system equipped with three types of combined LEDs with red (R, 655 nm), blue (B, 456 nm), green (G, 515 nm), and white (W, 456 nm + 558 nm) (R:B=8:2, R:W:B=8:1:1, R:G:B=8:1:1) and FL. The seedlings were grown under normal growth conditions ($20^{\circ}C$, $181{\pm}4{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$, 12 h photoperiod) for four weeks. Lettuce plants grown under FL had significantly higher leaf shape index than those under all LED treatments. Although growth of shoots and roots was not show any significant difference among LED treatments, all of the LED treatments induced about 34% higher shoot fresh weight than that of the FL. On the other hands, the total power consumption of FL was 145 kW for 4 weeks, while the mean value of LED treatments was 54 kW, which was about 3 times lower value than that of the FL. The light use efficiency based on dry matter in LED treatments was about 34 mg/W and this was about 3.5 times higher energy saving value than the FL. In conclusion, this study showed that irradiation of optimal combined LEDs in closed-type plant production systems can improve the lettuce growth as well as maximize in light use efficiency through energy saving than the FL.

• The KIPS Transactions:PartB
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• v.10B no.4
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• pp.381-388
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• 2003

This paper presents a method of giving weights to garbage class clustering and Filler model to improve performance of keyword spotting system and a time-saving method of dialogue speech processing system for keyword spotting by calculating keyword transition probability through speech analysis of task domain users. The point of the method is grouping phonemes with phonetic similarities, which is effective in sensing similar phoneme groups rather than individual phonemes, and the paper aims to suggest five groups of phonemes obtained from the analysis of speech sentences in use in Korean morphology and in stock-trading speech processing system. Besides, task-subject Filler model weights are added to the phoneme groups, and keyword transition probability included in consecutive speech sentences is calculated and applied to the system in order to save time for system processing. To evaluate performance of the suggested system, corpus of 4,970 sentences was built to be used in task domains and a test was conducted with subjects of five people in their twenties and thirties. As a result, FOM with the weights on proposed five phoneme groups accounts for 85%, which has better performance than seven phoneme groups of Yapanel [1] with 88.5% and a little bit poorer performance than LVCSR with 89.8%. Even in calculation time, FOM reaches 0.70 seconds than 0.72 of seven phoneme groups. Lastly, it is also confirmed in a time-saving test that time is saved by 0.04 to 0.07 seconds when keyword transition probability is applied.

• Korean Journal of Medicinal Crop Science
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• v.5 no.1
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• pp.67-71
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• 1997

Bupleurum falcatum is one of the oldest medicinal crop spontaneously generated as well as cultivated by man and successfully grown during the summer season in Korea. This study was conducted to examine the effect of planting density in the row spacing and hill spacing system using machine seeder on major agronomic traits, yield and labor saving. In 1993 and 1994, a spilt plot design was used with row spacing as the main plot and hill spacing as subplot. Labor saving efficency of the machine seeder reduced 96% than the hand seeding in sowing time required. Number of seeding stand increased, but stem height and number of nodes did not affect with different density in each row and hill spacing. There were reduced with narrow hill spacing on stem diameter, number of branches, shoot weight and root traits. There was no significant interaction between row and hill spacing for any major traits studied except shoot weight. Yield was more increase at 20cm than at 30cm row spacing. For these studies the optiomum density appears to be between drilling or 5cm hill spacing with 20cm row spacing. A highly significant positive correlation was appeared between number of seedling stand and root yield.

• Korean Journal of Agricultural and Forest Meteorology
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• v.3 no.4
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• pp.177-184
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• 2001

This study was conducted to identify the optimum nitrogen (N) fertilization at panicle initiation stage on ridge direct seeding on dry paddy of rice. During 1999~2000, a series of experiments was carried out at field (Chonbuk series) of the National Honam Agricultural Experiment Station, RDA using Dongjinbyeo. Plants were taller, and leaf area index and top dry weight increased with more N fertilization at panicle initiation stage. Photosynthetic rate of heading stage was higher at higher amounts of N fertilization at panicle initiation stage, especially in 6 kg/10a compared with 10 kg/10a seeding rate. Lodging index and its related traits did not significantly differ under different rates of N fertilization at panicle initiation stage. N uptake of the rice plant increased as more N fertilization at panicle initiation stage. N use efficiency was highest under the standard topdressing rate at 6 kg/10a seeding rate. Panicle number per m$^2$ increased with more topdressed N, but ripened grain rate and 1,000-grain weight of brown rice did not differ with an increase in topdressed N. Milled rice yield was 6% higher in the 6 kg/10a seeding rate and 13% higher in the 10 kg/10a seeding rate at 50% more topdressed N compared with 4.8 kg/10a N fertilization at panicle initiation stage of 6 kg/10a seeding rate.

• Horticultural Science & Technology
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• v.16 no.2
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• pp.247-250
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• 1998

This study was carried out to investigate the effects of changes of ionic strength according to growth stage on growth and flowering of Dendranthema grandiflorum (Ramat.) Kitamura 'Seiun' grown hydroponically in perlite. The stage I, II, and III covered early vegetative growth (27-40 days after planting), latter vegetative growth (41-54 days), and reproductive growth (55-80 days), respectively. The 2 strength (1S and 2S) of nutrient solution were treated in stage I, whereas 3 strengths (1S, 1-2S, and 2S) were treated in stage II. Then, total 9 treatments in stage III were designated by 3 treatments (tap water, 1S, and 2S) for each 3 strengths in stage II. Each nutrient solution was applied 8 times per day. At vegetative growth stage (54 days after planting), stem length was highest when irrigated 8 times a day with 1S nutrient solution. Both photosynthesis and transpiration rate were higher in 1S than those in other treatments (1-2S, 2S), whereas leaf chlorophyll content was highest in 2S treatment. Ion content of plant treated with 2S was higher than other treatments. Growth (plant height, leaf area, stem length), fresh weight, and dry weight of each plant organ after flower bud formation were better in tap water treatment (1-1-0) than other 1S treatments (1-1-1, 1-1-2). Regarding the number of days to flowering, tap water treatment was the most effective. Thus, after flower bud formation supplying tap water or lower concentration of nutrient solution than those used during the vegetative growth stage was economical in saving chemical fertilizers, shortening the number of days to flowering, reducing salt accumulation in media, saving efforts of leaching, and reducing ground water contamination.

• Journal of the Korean Recycled Construction Resources Institute
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• v.9 no.4
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• pp.642-649
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• 2021

Energy saving standard for buildings are strengthened, the application of exterior insulation finishing system and thickness of insulation materials are increasing. Most buildings with exterior insulation finishing system is applied organic insulating material. Organic insulating material have workability, economic feasibility, reduction in construction cost, and excellent thermal insulation performance. However, Organic insulating material is very vulnerable to heat, so when a fire occurs, rapid fire spread and toxic gas are generated, causing many casualties. Inorganic insulating material can be non-combustible performance, but it is heavy and has low thermal insulation performance. Mineral wool has higher thermal insulation performance than other types of inorganic insulating material, but mineral wool is disadvantageous to workability and vulnerable to moisture. Glass bubble are highly resistant to water and chemically stable substances. In addition, the density of the glass bubble is very low and the particles are spherical, fluidity is improved by the ball bearing effect. Glass bubbles can be used with cement-based ino rganic insulating material to impro ve the weight and thermal insulatio n perfo rmance o f cement-based inorganic insulation. This study produced a inorganic insulating materials were manufactured using cement-based materials and glass bubble. In order to evaluate the insulation performance and flame retardant performance of cement-based super light-weight inorganic insulating materials using with glass bubble, insulation performance or flame retardant and non-combustible performance were evaluated after manufacturing insulating materials using micro cement and two types of glass bubbles. From the test result, Increasing the mixing ratio of glass bubbles improved the insulation performance of cement-based super light-weight inorganic insulating materials, and when the mixing ratio of glass bubbles was 10%, it sho wed sufficient flame retardant and no n-co mbustible perfo rmance.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.34 no.4
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• pp.51-60
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• 2002

This study was carried out to develop the biochemical pulping method to enhance energy saving and decrease the capital cost through the soda pulping under atmospheric pressure (100%). Nonwood substrates, rice straw, were pretreated by white-rot fungi, Ganoderma Iucidum. It has acquired several basic data that can be applied in bio-soda pulping. The results of this study were as follow. Without any nutrients or with glucose, N and glucose+N the weight losses of rice straws inoculated by Canoderma Iucidum were 8.5~29.8%, 9.3~32% 11.8~30.1% and 11.8~24.4% respectively for 5, 10, 15, 20, 25 and 30 days incubation. The more extending incubation periods, the more increasing weight losses. The yield of untreated rice saw was 54.8% after pulping. When any nutrients was not added or glucose, N and glucose+N were added for the pretreatment, the total yields were ranged 50.6~38.5%, 48.6~34.4%, 47.2~38.4% and 49.5~42.6% respectively for 5, 10, 15, 20, 25 and 30 days incubation. The yields were gradually decreased based on extending of incubation. The physical properties of rice straw soda pulps without fungal treatment, the density, breaking length, burst index, tear index and folding endurance were 0.24 g/$\textrm{cm}^3$, 2.32 km, 0.91 kPa $m^2$/g, 56.7 mN.$m^2$/g and 35 times, respectively. After pretreatment without any nutrients or with glucose, N and glucose+N as nutrients the density was 0.27~0.30 g/$\textrm{cm}^3$, the breaking length 3.14~5.25 km, burst index 1.42~2.78 kPa.$\textrm{m}^2$/g, tear index45.8~64.5 mN.$\textrm{m}^2$/g and folding endurance 47~288 times at all incubating periods when pulping was done. The physical properties were increased with the increasing incubation periods. However, when glucose+N was added, the physical properties were shown superior results each incubating duration.