• Journal of Korea Society of Industrial Information Systems
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• v.14 no.4
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• pp.116-127
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• 2009

This research aims to improve the efficiency of production by selecting production configuration with high yield rate and lower error rate based on production history of steel pipe. To achieve this, we identify the properties of various types of MTO(make-to-order) steel pipe products and determine properties affecting yield rate and error rate using decision tree technique. From experimental results, we find out that specification is critical to determine yield rate and error rate of ERW steel pipes with mostly small and medium caliber, and an external diameter range in case of roll benders or spiral steel pipes with mostly large caliber. This research classified and embodied the patterns of yield rate and error rate mathematically by product properties.

• Korean Chemical Engineering Research
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• v.44 no.6
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• pp.650-658
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• 2006

The recycling of TDA from solid waste of TDI plant(TDI-R) by near-critical hydrolysis reaction had been studied by means of a statistical design of experiment. The main and interaction effects of process variables had been defined from the experiments in a batch reactor and the correlation equation with process variables for TDA yield had been obtained from the experiments in a continuous pilot plant. It was confirmed that the effects of reaction temperature, catalyst type and concentration, and the weight ratio of water to TDI-R(WR) on TDA yield were significant. TDA yield decreased with increases in reaction temperature and catalyst concentration, and increased with an increase in WR. As a catalyst, NaOH was more effective than $Na_2CO_3$ for TDA yield. The interaction effects between catalyst concentration and temperature, WR and temperature, catalyst type and reaction time on TDA yield had been defined as significant. Although the effect of catalyst concentration on TDA yield at $300^{\circ}C$ as subcritical water was insignificant, the TDA yield decreased with increasing catalyst concentration at $400^{\circ}C$ as supercritical water. On the other hand, the yield increased with an increase in WR at $300^{\circ}C$ but showed negligible effect with WR at $400^{\circ}C$. The optimization of process variables for TDA yield has been explored with a pilot plant for scale-up. The catalyst concentration and WR were selected as process variables with respect to economic feasibility and efficiency. The effects of process variables on TDA yield had been explored by means of central composite design. The TDA yield increased with an increase in catalyst concentration. It showed maximum value at below 2.5 of WR and then decreased with an increase in WR. However, the ratio at which the TDA yield showed a maximum value increased with increasing catalyst concentration. The correlation equation of a quadratic model with catalyst concentration and WR had been obtained by the regression analysis of experimental results in a pilot plant.

• Journal of agriculture & life science
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• v.53 no.4
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• pp.77-92
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• 2019

The purpose of this study was to investigate the carcass characteristics and the primal cut yields from carcasses according to the sex of Hanwoo. Experimental animals comprised of 80 cows, 29 bulls, and 71 steers. After slaughtering, they were evaluated to estimate the productivity of carcass components by market weight, and to predict the beef carcass yield. The average of fasting weight of cow, bull and steer were 634.75 kg, 721.86 kg, and 754.10 kg respectively. Market weight of Hanwoo at cold carcass weight, primal lean cut weight, sub-primal lean cut weight, bone weight and fat weight were 381.01~467.60 kg, 240.79~310.36 kg, 208.27~276.47 kg, 57.23~76.28 kg and 89.19~138.97 kg respectively. Body measurement traits had side length, hindquarter length, cervical vertebrae length, lumbar vertebrae length, sacral vertebrae length, 6th lumbar vertebrae~heel length, 5~6th thoracic vertebrae breadth, 4~5th lumbar vertebrae breadth, 5th sacral vertebrae breadth, 7~8th thoracic vertebrae girth and 7~8th thoracic vertebrae thick were highest length in steer. Carcass weight (CW) were significantly (p<0.05) affected by sex and live weight. The lean meat percentage, fat percentage and bone percentage based on the weight of cold carcasses were significantly different (p<0.05) between sex groups. The primal cuts rate for deungsim, moksim, abdari, udun, suldo, yangjee and satae were higher in bulls than those of the caws and steers. The carcass by-product weight rate in steer had lower oxtail and rib cartilage than cow and bull, while cow showed lower beef leg bones and jappyeo than bull steer (p<0.05). Body measurement traits was always important for primal cut weight estimates.

• Journal of the Korean Society for Marine Environment & Energy
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• v.17 no.4
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• pp.268-273
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• 2014

Experiments on carbonization were conducted using fish offal generated from fish market for the purpose of resource recycling. Elemental composition of fish offal and effect of carbonation temperature on the overall yield were investigated. Carbon and hydrogen contents of fish offal were 51.1% and 7.6%, respectively in view of elemental composition. Particularly, nitrogen and sulfur contents were as high as 9.8% and 1.0%, respectively. These values suggests that odor problem of fish offal can be serious. Comparing elemental composition of fish offal with other waste materials, it is thought that carbon and hydrogen contents are considerably high. These implies that thermal disposal will be the best option for final disposal method of fish offal. As a results of carbonization experiments on Mackerel, Hairtail, Croaker and mixed sample of Mackerel, Hairtail and Croaker, carbonization patterns were quite similar irrespective of fish species. Carbonization yield was varied significantly depending on carbonization temperature at the carbonization time of 5 minutes and 10 minutes. When the carbonization time was maintained longer than 30 minutes, yield variation depending on time variation at each temperature was insignificant. Thus, it can be concluded that effect of carbonization time on overall yield was minor when the carbonization time was maintained longer than 30 minutes. Primary vaporization in carbonization conducted at the temperature of $400^{\circ}C$ was minor. Thus, difference of yield between temperature of $500^{\circ}C$ and $400^{\circ}C$ was appeared greatly. It can be concluded that yield difference depending on carbonization temperature can be neglected if the carbonizing temperature exceed $600^{\circ}C$ and carbonizing time exceed 10 minutes at the same time.

• Journal of the Korean Wood Science and Technology
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• v.10 no.3
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• pp.109-117
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• 1982

In order to investigate the annual mean equilibrium moisture content (EMC), the equilibrium moisture content investigated were the desorbed - and adsorbed equilibrium moisture content with two end-matched samples for red pine (Pinus densiflora S. et Z.), Douglas fir (Pseadotsuga menziesii Franco), oak (Quercus mongolica Fischer) and red lauan (Shorea spp.) in instrument screen at forest experiment station located in Seoul, Chuncheon, Daejeon, Kyungju, Jinju and Gwangju area for four years (1970. 1 - 1973. 12). The results summarized were as follows. 1. The annual mean desorbed equilibrium moisture content of red pine, Douglar fir, oak and red lauan were 14.8, 13.7, 14.0 and 14.2 percent respectively and higher than the annual mean adsorbed equilibrium moisture content of those species. 2. The annual mean desorbed - and adsorbed equilibrium moisture content in central areas (Seoul, Chuncheon, Daejeon) were higher than those in southern areas (Kyungju, Jinju, Gwangju). 3. On the whole, the monthly mean desorbed - and adsorbed equilibrium moisture content were lowest in April and highest in August though difference of month in areas. 4. Average and range of annual national equilibrium moisture content was 12.3 ~ 14.2 ~ 15.7 percent for desorbed equilibrium moisture content and 11.3 ~ 13.2 ~ 14.7 percent for adsorbed equilibrium moisture content and 12.0 ~ 14.1 ~ 16.4 percent for calculated equilibrium moisture content based on tempera.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.9
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• pp.1351-1357
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• 2016

Green tea (Camellia sinensis) seed extract (GTSE) was prepared under various pretreatment conditions and used to investigate its extraction yield and anti-yeast activity. Anti-yeast activity of GTSE from seeds with or without the coats was the same, whereas the extraction yield was slightly higher in extract from seeds without the coat. Anti-yeast activity of GTSE from seeds with different water contents or particle sizes was the same, whereas the extraction yield was highest in extract from seeds with 7.3% moisture or a smaller particle size. Anti-yeast activity of defatted green tea seed extract (DGTSE) was the same as that of GTSE. Extraction yield was higher in DGTSE from defatted seeds by the oil press machine compared to hexane extraction. Defatted green tea seed (DGTS), a by-product from the oil extraction process, is a good natural source of anti-yeast preservative. The extraction yield and anti-yeast activity of DGTSE were investigated using various extraction solvents, temperatures, and times. The results show that water was an economic extraction solvent, and anti-yeast activity of DGTSE was unstable at $90^{\circ}C$. These results suggest that water, extraction temperature of $50^{\circ}C$, and extraction time of 4 h were the most efficient for extraction of anti-yeast compounds from DGTS.

• Korean Journal of Food Science and Technology
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• v.21 no.4
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• pp.583-589
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• 1989

In order to improve the quality and yields of barley tea(water extracts), enzymatic hydrolysis was carried out with using three kinds of mired enzymes of ${\alpha}-amylase,\;{\beta}-amylase$ and protease. The barley treated with enzymes were the crushed , soaked and slightly roasted(light brown) Youngsanbori(hulless) and the physical, chemical and sensory characteristics were investigated. The results showed that enzymatic hydrolysis caused a signigicant increase in solid yields (80%) of barley tea, particularly with the mixed enzyme 5,000 which has higher activity of ${\alpha}-amylase$ than the other enzymes. The intrinsic viscosity of barley tea was reduced by enzymatic hydrolysis as the value of dextrose equivalent increased The Hunter L, a, b values was lower for the enzyme treated barley tea but showed not significant difference with reaction time. The organoleptic evaluation clearly showed that both intensity and acceptability of odor and taste was markedly Increased. The roasted nutty, and sweety odor and taste were particular in increase by mixed enzyme 5,000.

• KSBB Journal
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• v.9 no.4
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• pp.365-371
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• 1994

The effects of ratios of initial concentration of carbon source to the initial concentration of nitrogen source in the fermentation media on both the yields of PHB fermentation variables and the accumulation of poly-${\beta}$-hydroxybutyric acid(PHB) were investigated. The fermentation media were composed of the combination of varing glucose concentrations, 10, 20, 25, 30, 40, $50g/\ell$ and the NH4Cl concentrations 0.33, 0.4, 0.5, 1.5, 3, $5g/\ell$. The yield of biomass on glucos, Yx/s, decreased very slowly according to the increase of the ratio of C to N. And the yield became constant at 0.35(g biomass/g glucose) with the ratio higher than 70. The yield of residual biomass, Yx/s, also decreased with the ratio of C to N and finally showed a constant value of 0.065(g residual biomass/g glucose) when the ratio was higher than 65. In accordance with the augmentation of the ratio, the yield of PHB, YPHB/S, however, increased and showed the maximum value of 0.35 (g PHB/g glucose) between 40 and 60 of the ratio. The maximum yield of PHB to the change of biomass, YPHB/S, was 0.87(g PHB/g biomass), and the yie1d YPHB/RX, was 4.2(g PHB/g residual biomass). The maximum accumulation percent of PHB to the final biomass was 81% when the ratio was higher than 67.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.38A no.4
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• pp.360-370
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• 2013

When best-effort traffic users are supported in a downlink small-cell network, conventional schemes assign the channels experiencing low co-channel interference at each base station and provide a better downlink performance to the user near its serving base station, so that conventional schemes are not suitable to fairly support all users. In this paper, we propose a decentralized frequency reuse scheme for a small-cell network, where each basestation chooses a set of channels to fairly support the best-effort traffic users regardless of the distances to their serving basestation. After performing the conventional scheme that each basestation selects the channels which are not used in its adjacent basestations, it updates assigned channels improving the performance of low throughput users in a fully distributed manner with mitigating the overall throughput performance loss. The computer simulation demonstrates that the average throughput performance of the 10th percentile throughput users is improved up to 15% in some case compared to that of the conventional scheme, while allowing the overall throughput loss around 3%.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.5
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• pp.899-904
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• 2004

The objectives of the experiment were to examine the effects of extrusion process variables on the yield of extruded ginseng extract and to determine the effect of ratio of extruded ginseng extract and microcrystalline cellulose on characteristics of spheronized granules by cold extrusion-spheronization process. Extrusion process variables observed were feed moisture (15, 22, 29%), die temperature (90 110 13$0^{\circ}C$) and screw speed (150 200, 250 rpm). The results showed that moisture content of dried ginseng significantly affected extraction yield (P<0.05). The less moisture content of the feed resulted in the higher yield of the extract. Moisture content of 15%, screw speed of 250 rpm and die temperature of 13$0^{\circ}C$ gave the highest yield of ginseng extract. Mean extraction yield of extruded ginseng using hot water extraction was greatly improved by extrusion process The extract yield of extruded ginseng was 43.5% which was higher than that of red ginseng (38.3%) and white ginseng (29.0%) produced by traditional process. It was possible to make from the mixture of microcrystalline cellulose (200 g) mixed with different concentration of 200 mL solution (0, 5, 20, 30 40 50 60% of ginseng extract with 59.2% dry solid) by using cold extrusion spheronization. When the concentration of ginseng extract Increased, the granulation yield was improved but friability and compression index were reduced. Ginseng extract such as saponin was completely released from spheronized granules in distilled water within 10 min. It can be concluded that spheroniged granule with ginseng extract could be packed in gelatin capsule since granules Possessed proper physical properties and quick release of saponin.