• KSBB Journal
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• v.10 no.4
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• pp.455-460
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• 1995

Specific growth rate was controlled for the repression of acetic acid formation in the fed-batch fermentation of recombinant Escherichia coli. With controlled specific growth rate, we studied the effect of the specific growth rate on cell growth, glucose consumption, acetic acid formation, and the expression of recombinant protein (${\beta}$-lactamase). High specific growth rate caused the accumulation of glucose and acetic acid, and lowered the production of recombinant protein. However, the addition of methionine recovered the gene expression by alleviating the negative effect of acetic acid at high specific growth rate.

• Journal of Environmental Health Sciences
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• v.3 no.1
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• pp.22-26
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• 1976

Korea Parasite Eradication Association alleged in its seasonal spring report in 1975 that 36.8 percent of primary, middle and high school students in Seoul area are infected with parasites. Such a high rate of infection is a result of having used raw excrement for manure. Soil is, therefore, to a large extent infected with parasite eggs. In order to present helpful reference materials for preventing parasite infection in the area where human feces have been used for manure, soil in Seoul area and the suburban districts is sampled at random and then the rate of infection in various areas and the variation of infection rate in the same area are studied. The results are as follows 1) The parasite infection rates the according to districts are, Sootaik-ri 39.9%, Chamsil-dong14.2%, Songpa-dong 13.2%, Sageun-dong 12.8% Chayang-dong 11.4%, Sungsoo-dong 8.5%. The above figures show that the rate becomes higher as the area is farther from the urban and residential districts and nearer to the rural area. 2) The rates of detected parasites according to their kinds are as follows Ascaridae 55.9%, Ancylostomatidae 19.9%, Trichocephalus 13.5%, Trichostrongylus 5.7%, Tenia 3.9%, Enterobius 1.1% 3) The monthly variation of infection rate in the same districts, in the case of Sageun-dong, is, August 25.7%, July 18.9%, June 16.2%, September 15.3% April 12.6%, May 11.3%. The above shows that the infection rate of soil is comparatively higher in the summer season.

• Asian Journal of Turfgrass Science
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• v.9 no.3
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• pp.173-185
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• 1995

Hydroseeding technique is a very popular method of revegetating slope areas through the control of soil erosion and stability by seeding grasses. This study was conducted to select turfgrass species and cultivars for hydroseeding. Experiment plots were established on various soil types and environmental conditions at Singar-Ansan high-way construction site. The investigation was designed in three cutting, one back-filling and other three spare sites with various seed mixtures. Results indicated that combinations of seed mixtures influenced seed germination and rates of surface cover. In a view of long term, vegetation shifts should be influenced by characters of slopes and micro-climate conditions. Hydroseeding did not show good results on rocky slope areas. Revegetation was only going on where there had soil. The combination of seed mixture with a higher rate of perennial ryegrass had relatively good revegetation with faster germination and seedling growth. Improved turf-type tall fescue Arid ⓡ and Falcon ⓡ seemed to have good environ-mental adaptation and drought tolerance. Wild or old type cultivars showed relatively slow green-up in spring and growth rates at the next year of seeding. For the harmonious landscaping with surrounding area, the combination of native grass mixture with cool-season grasses had good results. Slow and low revegetation rate at hack-filling site seemed to be caused by the poor development of capillary tubes in sub-soil. It was shown that a high correlation between seed germination and revegetation rate, and between three-month later coverage rate and final rate. The evaluation of coverage rate after three month seems to he acceptable to decide the accomplishment of hydroseeding results on rode side slopes.

• Journal of Animal Science and Technology
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• v.65 no.1
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• pp.32-56
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• 2023

This review explores the factors that improve meat protein digestibility and applies the findings to the development of home meal replacements with improved protein digestion rates in older adults. Various methods improve the digestion rate of proteins, such as heat, ultrasound, high pressure, or pulse electric field. In addition, probiotics aid in protein digestion by improving the function of digestive organs and secreting enzymes. Plant-derived proteases, such as papain, bromelain, ficin, actinidin, or zingibain, can also improve the protein digestion rate; however, the digestion rate is dependent on the plant enzyme used and protein characteristics. Sous vide processing improves the rate and extent of protein digestibility, but the protein digestion rate decreases with increasing temperature and heating time. Ultrasound, high pressure, or pulsed electric field treatments degrade the protein structure and increase the proteolytic enzyme contact area to improve the protein digestion rate.

• Journal of Distribution Science
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• v.22 no.9
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• pp.27-38
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• 2024

Purpose: Sustainable economic growth is a top priority for any country, and inflation is crucial in determining future economic circumstances. Few research exists regarding the impacts of risk management practices on performance outcomes in the supply chain with the mediating role of inflation rate. Hence, this study investigates the important role of risk management practices in the context of high inflation rate. Research design, data and methodology: The PLS-SEM model is applied to identify the effects of risk management practices on operational performance and supply chain performance. The author distributed online and offline surveys to administrators at various businesses. After applying the filtration criteria, 309 responses were retained for further data analysis. Results: This research demonstrates that risk management practice is critical and adds to supply chain performance success. Managers should enhance all risk management procedures to regulate and manage hazards in the supply chain. This allows managers to anticipate and identify potential threats with ease, particularly in high inflation rate situation. Conclusions: The outcomes of this study demonstrate how fully implemented risk management practices can improve operational performance and supply chain performance, as well as control the impact of inflation rate.

• Korean Journal of Agricultural Science
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• v.36 no.1
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• pp.87-98
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• 2009

The objective of this study is to evaluate the effect of increasing instream flow at Gapcheon stream of Daejeon city by considering two virtual reservoirs upstream, respectively; Geum-gok reservoir and Koe-gok reservoir upstream, respectively. The paralleled and cascaded reservoir operations were performed including the existing Jang-an and Bang-dong reservoirs. The results are summarized as follows. Firstly, from the Bang-dong and Geum-gok cascaded reservoir's water balance analysis, instream flow of $6.83Mm^3$ was able to be supplied to downstream, and water supply indexes of Geum-gok reservoir were analyzed to have the rate of water supply divided by watershed area of 403.4 mm, the rate of water supply divided by rainfall of 33.0 %, the rate of water supply divided by inflow of 96.4 %, the rate of water supply divided by storage capacity of 81.9 %, and the rate of inflow divided by storage capacity of 112.3 %. Secondly, from the Jang-an and Geum-gok paralleled reservoir's water balance analysis, flow durations at Gapcheon station were analyzed to have Q95 (the 95th high flow) of $4.806m^3/s$, Q185 (the 185th high flow) of $2.217m^3/s$, Q275 (the 275th high flow) of $1.140m^3/s$, and Q355 (the 355th high flow) of $0.887m^3/s$. Thirdly, inflow to Koe-gok reservoir was simulated including the Jang-an and Bang-dong paralleled reservoir's water balance analysis, instream flow of $49.60Mm^3$ was able to be supplied from Koe-gok reservoir to downstream, and water supply indexes of Koe-gok reservoir were analyzed to have the rate of water supply divided by watershed area of 246.5 mm, the rate of water supply divided by rainfall of 19.4 %, the rate of water supply divided by inflow of 40.8 %, the rate of water supply divided by storage capacity of 412.1 %, and the rate of inflow divided by storage capacity of 1,189.8 %. Fourthly, daily streamflows at Gapcheon stream were simulated including outflows from Koe-gok reservoir, flow durations at Gapcheon station were analyzed to have Q95 (the 95th high flow) of $4.501m^3/s$, Q185 (the 185th high flow) of $2.277m^3/s$, Q275 (the 275th high flow) of $1.743m^3/s$, and Q355 (the 355th high flow) of $1.564m^3/s$. The conclusion appeared that the effect of increasing instream flow at Gapcheon stream from Koe-gok reservoir was more higher than that from Geum-gok reservoir.

• Journal of Environmental Health Sciences
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• v.17 no.2
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• pp.54-66
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• 1991

As a result of measuring illumination and making up a question at home visit directly by investigator who trained over twenty days period from October 4 to 24, 1990, in order to render help which illumination problem against house, society against eyes or framing of health instruction potgram by seizing natural lighting actual conditions of house and actual conditions of wearing spectacles and by investigating interrelationship, I can summarize as follows. 1) In property of investigation subject, woman 66.9%, In an age, the twenties was largest of 27.4%, the forties was 20.2%, the fifties was 18.6%, the thirties was 17.4%. In academic career, those of upper secondary school grauates was largest of 28.6%, those who possess university career was 25.9%, those who middle school career was 20.9%, decoding of Korean alphabet was 2%. 2) By a residence area, a big city was 43.3%, farming and fishing villages were 20.3%, the rest was a small town and the administrative office of town, township. In positon of house, the middle area was 43.6%, resident of suburb area was 38.0%. In form of house, a Korean-style house was 40.8%, a western-style house was 34.8%, an apartment house was 11.0%. In the a standard of living, the middle classes 77.2%, the lower classes were 15.3%. In residential house unit of area, from 21 to 30 unit of area was largest of 31.5%, from 10 to 20 unit of area was 19.9%, from 31 to 40 was 18.7%. 3) The wearing spectacles rate of study user was 44.1%. By the area, those who wearing spectacles was more than a half of 50.8% in the resident of big city area. As passing from the farm area to the city, that is being resident of big city was high wearing spectacles rate. In position of house, as being residence in central street showed high wearing spectacles rate. (central street was 51.5%, the middle area was 44.5% and the suburb area was 40.1%.) It seemed similarity difference a variable by position of house from wearing spectacles in standard of 1%. By form of house, wearing spectacles rate those who resident in apartment house was 49.5%, that rate those who resident in a western-style house was high of 49.0%, that rate those who resident in a Korean-style house was the lowest 39.0%. By social position of resident in room, in students case who study showed very high, as university students were very high of 62.3% idn wearing spectacles rate, middle and high school students 'were 50.0%, members of society were 47.6%, workers 20.3%. It seemed similarity difference from academic career in standard of 1%. By an age, the thirties was high of 54.1% in wearing spectacles rate, the twenties was 43.2%, the teenage was the lowest of 11.8%. 4) In illumination of study, over 200Lux was high of 40.1%. but below 99Lux which inappropriate illumination to see the books was 32.4%. Average by area, below 99Lux was 22.7% and over 400Lux was 50.0% in case of wooden floor. As examine by area, below 99Lux was high of 27.0% a case of wooden floor in the big city area, it was not good in illumination passing from the farm area(15.0%) to the city(19.0%). Average illlumination by area of the main living room below 99Lux was high of 37.5%, less than 200Lux was 58.5% of whole. In general, illumination of the main livingroom was inappropriate. By area, the big city was 32.5% below 99Lux, the middle and small city area were 33.8%, town and township area were 45.0%, farming and fishing area were 42.8%. By area, in the big city, illumination of study was 52.5% over 200Lux and 28.9% below 99Lux. In case of the middle and small city, study user of below 99Lux was 38.8% and over 200Lux was 46.9%. In case of the seat of town township, below 99Lux was 34.1% and over 200Lux was 39.7%. In case of farming and fishing area, illumination of study was 33.4% below 99Lux and 48.4% over 200Lux. It tends to high rate of inappropriate illumination. 5) By position of house, in case of wooden floor, less than 100Lux was 24.5% in central street. It was bad illumination than others position of house. In case of the main livingroom, less than 100Lux was 40.4% in the suburb area. It was bad iliumnation than others position of house. In case of study, less than 100Lux was 35.4% in the middle area, it was worse in illumination. In case of the main living room, is seemed similarity difference in standard of 1%. 6) By form of house, in case of wooden floor, illumination of less than 100Lux was 23.8% in a western-style house, it was bad illumination than others form of house. In case of the main livingroom, illumination of less than 100Lux was 47.4% in a Korean-style house, it was remarkably bad illumination than others form of house. In case of study, a Korean-style house was 38.8%, it was very bad illumination than others form of house. In case of the main livingroom and study, it seemed similatrity difference each as P < 0.01 and P < 0.05 in standard of 1%. 7) The wearing spectacles rate of those who use room of illumination over 400Lux was 40.7%, and that of those who use room of illumination less than 100Lux was 28.1%. It seemed similarity differecce in standard of 1%. 8) In period of wearing spectacles, 21.3% of total investigator-highest-was from before five years, 8.6% was from before three years. Among those who use of illumintion less than 99Lux, 34.0% began to wear spectacles from before two years 31.7% was from before five years, 30.3% was from before four years. It seemed similarity difference from period of wearing spectacles by illumination in standard of 1 %. 9) Among cause which sight grow worse, the first was that it was each 33.2% and 27.4% in response rate because watch TV nearly to wearing spectacles person and non-wearing person. The second was that a lot of seeing books was 25.3% in wearing spectacles person and response rate for dark illumination was 7.4% in nonwearing spectacles person. It seemed similarity difference in standard of 1%. (P < 0.01). 10) In experience which take medicine good for eyes, it was 50.1% in wearing spectacles person and 8.5% in non-wearing spectacles person. It seemed similarity difference in standard of 1%(P < 0.01). As we have seen above, inappropriate illumination can be a cause of wearing spectacles. Nevertheless, actually, is realities to indifferent against illumination of house. So it must learn knowledge about health obstacle of illumination through society instruction and school eduction against students as well as general residents. In case that natural lighting is inappropriate structural of house, we must be able to maintain appropriate illumination through artificial illumination. And so eyes which is core of human life have to be protected, related the authorities, related group, and all health medical personnel will organically cooperate with and make efforts.

• Journal of Bio-Environment Control
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• v.19 no.4
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• pp.203-209
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• 2010

This study was performed to investigate photosynthetic responses of 4 foliage plants in relation to light intensity, carbon dioxide concentration, and media, and to select efficient plants for the indoor environment control based on the results. Four foliage plants used in this study included Syngonium podophyllum, Schefflera arboricola cv. Hong Kong, Dieffenbachia amoena, and Dracaena deremensis cv. Warneckii Compacta. The plants cultivated in two different growth media, peatmoss and hydroball, and subjected to various light intensities (0, 30, 50, 80, 100, 200, 400, and $600\;{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ PPFD) and $CO_2$ levels (0, 50, 100, 200, 400, 700, 1000, and $1500\;{\mu}mol{CO_2}{\cdot}mol^{-1}$). As a result of the photosynthetic rate of foliage plants according to change of light intensity and $CO_2$ levels, Schefflera arboricola and Dieffenbachia amoena showed high apparent quantum yield, which stands for the photosynthetic rate under low light intensity, and both plants also recorded higher photosynthetic rate under high $CO_2$ concentration compared to the other two indoor plants. Dracaena deremensis showed the lowest photosynthetic rate under the low light intensity or high $CO_2$ concentration. There were inconsistent results in photosynthetic rate of foliage plants grown in peatmoss or hydroball. Higher photosynthetic rate was observed in Schefflera arboricola with peatmoss rather than hydroball as light and $CO_2$ concentration increased. However, hydroball had a positive effect on Dieffenbachia amoena in terms of photosynthetic rate. In case of Syngonium podophyllum, peatmoss induced higher photosynthetic rate according to increased light intensity, but there was no effect of media on the rate under various $CO_2$ treatements. In contrast, media did not affect to photosynthetic efficiency of Dracaena deremensis subjected to various light intensities and the rate of Dracaena deremensis with peatmoss was a little high when $CO_2$ concentration increased. In conclusion, potential plants for the indoor air pulification and environmental control were Schefflera arboricola and Dieffenbachia amoena because they showed high photosynthetic rate under typical indoor conditions, low light intensity and high $CO_2$ concentration.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2016.11a
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• pp.3-32
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• 2016

High power impulse magnetron sputtering (HiPIMS) technique has been developed for more than 15 years. It is characterized by its ultra-high peak current and peak power density to obtain unique thin film properties, such as high hardness, good adhesion and tribological performance. However, its low deposition rate makes it hard to be applied in industries. In this work, the development of HiPIMS system and integration of radio frequency (RF) or mid-frequency (MF) power supplies were introduced. Effects of duty cycle and repetition frequency on the microstructure, mechanical property, optical and electrical properties of some binary, ternary and quarternary nitride coatings and oxide thin films were discussed. It can be observed that the deposition rate was effectively increased by the superimposed HiPIMS with RF or MF power. High hardness, good adhesion and sufficient wear resistance can be obtained through a proper adjustment of processing parameters of HiPIMS power system.

• Journal of the Korean Society of Combustion
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• v.9 no.4
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• pp.22-27
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• 2004

Lean premix combustion is a best method in low $NO_x$ gas turbine combustor and we must know the characteristics of NO emission in high temperature and pressure condition in premix flame. Numerical analysis was performed to investigate the NO emission characteristics by adopting a counterflow as a model problem using detailed chemical kinetics. Methane $(CH_4)$ was used as a test fuel which is the main fuel of natural gas. The tested parameters were stretch rate, equivalence ratio, initial temperature, and pressure in premix flame. Results showed that NO emission was high in low stretch rate, near stoichiometric equivalence ratio, high initial temperature, and high pressure. Also, the pressure effect was sensitive in high temperature condition.