• Journal of Korean Society of Transportation
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• v.21 no.4
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• pp.113-132
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• 2003

Using nonradial data envelopment analysis(DEA) under assumptions of strong disposability and variable returns scale, this paper annually estimates productive. technical and allocative efficiencies of three publicly-owned rail transit properties which are different in terms of organizational type: Seoul Subway Corporation(SSC, local public corporation), the Seoul Metropolitan Electrified Railways sector (SMESRS) of Korea National Railroad(the national railway operator controlled by the Ministry of Construction and Transportation(MOCT)), and Busan Urban Transit Authority (BUTA, the national authority controlled by MOCT). Using the estimation results of Tobit regression analysis. the paper next computes their true productive, true technical and true allocative efficiencies, which reflect only the impacts of internal factors such as production activity by removing the impacts of external factors such as an organizational type and a track utilization rate. And the paper also computes an organizational efficiency and annually gross efficiencies for each property. The paper then conceptualized that the property produces a single output(car-kilometers) using four inputs(labor, electricity, car & maintenance and track) and uses unbalanced panel data consisted of annual observations on SSC, SMESRS and BUTA. The results obtained from DEA show that, on an average, SSC is the most efficient property on the productive and allocative sides, while SMESRS is the most technically-efficient one. On the other hand. BUTA is the most efficient one on the truly-productive and allocative sides, while SMESRS on the truly-technical side. Another important result is that the differences in true efficiency estimates among the three properties are considerably smaller than those in efficiency estimates. Besides. the most cost-efficient organizational type appears to be a local public corporation represented by SSC, which is also the most grossly-efficient property. These results suggest that a measure to sort out the impacts of external factors on the efficiency of rail transit properties is required to assess fairly it, and that a measure to restructure (establish) an existing(a new) rail transit property into a local public corporation(or authority) is required to improve its cost efficiency.

• Korean Journal of Weed Science
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• v.5 no.1
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• pp.73-84
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• 1985

25 tank-mixed combinations between Haloxyfop-methyl at 0, 0.05, 0.1, 0.15 and 0.2 kg ae/ha and Acifluorfen at 0, 0.082, 0.163, 0.245 and 0.326 kg ai/ha were applicated at post-emergence on the late-season cropped soybean(Glycine max) fields predominated by grasses and assessed on the weeding efficacy. A most abundant weed species on the experimented fields were found at September (25 species). The broadleaved weed species and sedges were successively and proportionately emerged by the control rate of grass species. From the mono-treatment of each herbicide, Haloxyfop-methyl was recognized as a highly selective one between grasses and soybean, and Acifluorfen between broadleaf weeds and soybean, respectively. By combined application with both herbicides a synergistic weeding efficacy was detected on total weed species, however antagonistic or additive on each weed groups. Among other traits of soybean, stem dry weight was influenced by weed competitions during October, number of pods per plant during August and seed yields during whole periods. For most effective and reasonable weeding, no less than 0.4 kg ai/ha of each herbicides should be applicated in combinations.

• Pediatric Infection and Vaccine
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• v.18 no.2
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• pp.124-134
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• 2011

Purpose : We have tried to search all concerning data on the policies of hepatitis B vaccination or surveillance of medical equipments that can transmit blood mediated diseases, including disposable syringe, in Republic of Korea, to propose references to other medical professionals. Methods : Data from domestic journals, government websites, computerized newspapers, etc. were reviewed. The data were arranged into four categories (governmental policies on hepatitis B control, hepatitis B mass immunization program in school, using process of hepatitis B vaccine, and policies on medical equipments surveillance, including disposable syringes, which is considered as source of blood mediated infection), and the periodic changes on each subjects in policies were reviewed. Results : Due to growing social concerns on hepatitis B in early 1980s, swift introduction and production of hepatitis B vaccine was made. After establishment of "5 year project for eradication of hepatitis B" in late 1983, number of vaccinated population jumped up to 6 million within 2 years (1984-85). However, since the immunization targets were mainly adult, not infant, this project was annulled in late 1985. Following this project, hepatitis B mass immunization program in school was carried out. In year 1995, hepatitis B vaccine was included in national immunization program. The use of disposable syringe was recommended from year 1980 but legislated in year 1985, finally. Conclusion : The mainstay in controlling hepatitis B in Republic of Korea was coordination of prompt introduction of vaccine, mass immunization, high vaccination coverage rate, or use of disposable syringes. However, since there is lack of official data available, it is urgent to arrange and computerize all government data related to infectious diseases.

• Horticultural Science & Technology
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• v.33 no.5
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• pp.638-646
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• 2015

To increase the utility of seeds in plant resources, seeds of 6 Aster species(A. incisus, A. hayatae, A. koraiensis, A. scaber, A. spathulifolius, and A. yomena) were subjected to experiments to develop adequate methods for sprout production. To study optimum germination conditions, germination rates of the seeds were analyzed at different temperature (15, 20, 25, and $30^{\circ}C$) and light conditions. A longitudinal growth experiment was performed in dark conditions for 10 days. Seedlings, with optimum germination rate and longitudinal growth, were placed in the light for 0-3 days to seek the adequate greening periods. Sprouts grown under optimum environmental conditions were placed in vessels with or without ventilation, and stored under $4^{\circ}C$ and $10^{\circ}C$ to examine storage environment and period. As a result of this analysis, seeds were selected that germinated over 50% within 12 days. Longitudinal growth was promoted at $20-25^{\circ}C$, and optimum growth was obtained with 7-9 days. As greening days increased longitudinal growth was retarded, but orbital growth of radicles and cotyledons was promoted. Considering all these factors, greening treatment of 2 days showed the best results. In a storage ability experiment, the best result was achieved by storage in vessels without ventilation under $4^{\circ}C$. Ventilation prevented rotting of sprouts, but reduced moisture contents of sprouts. Most sprouts were fresh at $4^{\circ}C$ for 3-6 days. In particular, sprouts of A. hayatae and A. yomena had high keeping quality, and remained fresh over 3 days even at $10^{\circ}C$.

• Food Science of Animal Resources
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• v.30 no.3
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• pp.449-457
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• 2010

This study investigated the effects of three kinds of water extract mixtures each with different ratios of A. capillaris, C. sinensis, S. chinensis, and V. coloratum on laying performance, egg quality, blood characteristics, and egg storage stability in laying hens. One hundred and sixty 35-wk-old laying hens (Hy-line brown) were divided into four groups of 10 birds each replicated times four. The treatments involved a basal diet (C, control) or diets containing three kinds of water extract mixtures at 200 ppm (T1, water extract mixture A; T2, water extract mixture B; T3, water extract mixture C). The egg production rate, egg mass, and feed conversion ratio were significantly improved in all treatments compared to those of control (p<0.05). Haugh unit and egg yolk color in all treated groups were significantly improved in comparison with control (p<0.05), but no significant differences were observed for egg shell quality. The content of total cholesterol in blood serum was significantly decreased in all treatments compared to that of control (p<0.05). The blood biochemical parameters of liver and kidney damage were significantly decreased in all treatments compared to those of control (p<0.05). Total antioxidant activity in the blood serum of all treated groups was increased as well. The Haugh unit and malondialdehyde content in the egg yolk during storage were significantly decreased in all treated groups compared to control (p<0.05). Consequently, the dietary supplementation of water extract mixtures of A. capillaris, C. sinensis, S. chinensis, and V. coloratum improved laying performance and egg quality but decreased egg quality deterioration with increased storage. These results suggest that medicinal plant extracts could be used as a feed additive in feed for laying hens.

• Korean Journal of Food Science and Technology
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• v.32 no.6
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• pp.1278-1284
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• 2000

The study was performed to elucidate the effects of ethylene-absorbent on the quality of 'Fuyu' persimmon fruits in the MA package. Five persimmons were packed in a MA package film (low density polyethylene, 0.055 mm film thickness), and stored at $-0.5^{\circ}C$ for 60 days. Two persimmons were repacked in a MA package with or without ethylene absorbent $(1\;M\;KMnO_4+zeolite)$ and stored at $-0.5^{\circ}C$. Ten days later, these packages was moved to $2^{\circ}C$ or $25^{\circ}C$ storage room to examine the effect of the ethylene-absorbent on the quality of the fruits. Ethylene removal by enclosed ethylene absorbent in MA packaging reduced the rate of fruit respiration at $25^{\circ}C$, so that $O_2$ and $CO_2$ concentration in packing were maintained higher and lower, respectively, compared to control. These effects were not observed, however, in $2^{\circ}C$ post-storage. Fruit firmness and sugar composition were also influenced by ethylene absorbent, showing more delayed flesh softening and higher sucrose concentration in ethylene absorbent treated fruits than control. But ethylene-absorbent treatment lowered glucose and fructose concentration. That shows that ethylene could influence on sugar composition by inhibiting sucrose inversion to glucose and fructose. The production of ethanol and acetaldehyde was reduced by ethylene removal, but the effect was not so high as other quality indices.

• Journal of Korean Society of Forest Science
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• v.90 no.1
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• pp.83-89
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• 2001

This study was conducted to test the Cd accumulation and Cd-tolerance of Pisotithus tinctorius(Pt). Pt was isolated from Pinus thunbergii forest in Muan, Chonnam Province in 1997. Pt was cultured on MMN medium supplemented with $CdSO_4{\cdot}5H_2O$ at the final concentration of 0, 0.2, 0.5, 2, and $10{\mu}g/m{\ell}$ for 40 days. Growth rate and tolerance index of the fungus were measured every week, while Cd concentration, superoxide dismutase(SOD), and glutathione reductase(GR) of the fungus were analyzed at the end of the culturing, Pt showed growth reduction in vitro at $2{\mu}g/m{\ell}$ Cd in the medium and almost stopped growth at $10{\mu}g/m{\ell}$ Cd. Tolerance index of Pt decreased with increasing Cd concentration. Cd concentration of Pt was the highest at $10{\mu}g/m{\ell}$ Cd. Activities of SOD did not show significant difference between Cd concentrations, but GR of Pt increased at $0.5{\mu}g/m{\ell}$ Cd, and decreased at $2{\mu}g/m{\ell}$ Cd. Consequently Pt could be called Cd accumulator with a tolerance mechanism to Cd. Their tolerance to Cd were expressed through the higher production of antioxidants such as GR. Pt may be used for revegetation and decontamination of soil polluted by heavy metals.

• Applied Chemistry for Engineering
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• v.30 no.5
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• pp.569-579
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• 2019

In this study, the effect anti-oxidant, anti-inflammatory, and liver protective activity was investigated via quick ultrasonic disintegration of pine pollen using a probe sonicator (PS) followed by the extraction with water, 70% ethanol, and 100% ethanol. The anti-inflammatory effect was studied by measuring the production of nitric oxide (NO) and cytokine in RAW264.7 cells induced with lipopolysaccharides (LPS). The cell toxicity was also checked with an 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, and the experiment was conducted using non-toxic $100{\mu}g/mL$. The NO inhibition rate was highest in the 70% ethanol PS group at $85.99{\pm}0.12%$. Also an excellent efficiency was obtained from the results of interlukin-1 beta ($IL-1{\beta}$) and tumor necrosis factor alpha ($TNF-{\alpha}$), which is related to inflammation-related cytokine, with the respective inhibition rates of 63 and 22%. To examine liver protective activity, HepG2 cells were treated with Taclin, and the generation of glutamic oxaloacetic transaminase (GOT) and lactate dehydrogenase (LDH) was measured in the culture solution. From GOT and LDH generation results, the inhibition rates in the 70% ethanol PS group were 28% and 13%, respectively, which was higher compared to that of using negative control group. Our results suggest that pine pollen extracted in 70% ethanol using PS may be used to develop food products that have anti-aging, anti-inflammatory, and liver protective effects.

• The Journal of the Petrological Society of Korea
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• v.23 no.3
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• pp.239-247
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• 2014

The (U-Th)/He dating utilizes the production of alpha particles ($^4He$ atoms) during natural radioactive decays of $^{238}U$, $^{235}U$ and $^{232}Th$. (U-Th)/He age can be determined from the abundances of the parent nuclides $^{238}U$, $^{235}U$ and $^{232}Th$ and the radiogenic $^4He$. Because helium is one of the noble gases (non-reactive) with a relatively small radius, it diffuses rapidly in many geological materials, even at low temperatures. Therefore, ingrowth of $^4He$ during radioactive decay competes with diffusive loss at elevated temperatures during the geologic time scale, determining the amount of $^4He$ existing today in natural samples. For example, He diffusion in apatite is known to be very rapid compared to that in most other minerals, causing a significant diffusive loss at ${\sim}80^{\circ}C$ or higher. At ${\sim}40^{\circ}C$, He diffusion in apatite becomes slow enough to preserve most $^4He$ in the sample. Thus, an apatite's (U-Th)/He age represents the timing when the sample passed through the temperature range of $80-40^{\circ}C$. The crustal depth corresponding to this temperature range is called a "partial retention zone." Normal closure temperatures for a typical grain size and cooling rate are ${\sim}60-70^{\circ}C$ for apatite and ${\sim}200^{\circ}C$ for zircon and titanite. Because the apatite He closure temperature is lower than that of most other thermochronometers, it can provide critical constraints on relatively recent or shallow-crustal exhumation histories.

• Food Science and Preservation
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• v.15 no.5
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• pp.635-641
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• 2008

This study was conducted to investigate the optimal sub-zero temperature for storage of two garlic cultivars, the northern ecotype 'Jaerae' and the southern ecotype 'Daeseo'. These cultivars of garlic bulbs were stored at different temperature (room temperature, $0^{\circ}C$, and $-4^{\circ}C$) conditions after predrying. Southern ecotype garlic showed higher weight loss than northern ecotype garlic. Northern ecotype garlic at $-4^{\circ}C$ exhibited less than 5% of weight loss during 10 month storage. Sprouting rate was higher in southern than in northern ecotype at room temperature storage. The value of injury by disease and insect was similar between southern ecotype and northern ecotype for 5 month storage, and then northern ecotype showed higher value of injury by disease and insect than southern ecotype. Hunter 'b' value of northern ecotype garlic was the lowest at $-4^{\circ}C$ storage. Northern ecotype garlic showed no cold injury at freezing point temperature storage. However, southern ecotype garlic had $0{\sim}5.3%$ cold injury occurrence at $-4^{\circ}C$ storage. Respiration and ethylene production exhibited the highest at room temperature storage, those had the slight increase at $0^{\circ}C$ and $-4^{\circ}C$ storages. Northern ecotype showed higher enzymatic pyruvic acid and fructan contents than those of southern ecotype. Enzymatic pyruvic acid content increased and fructan contents decreased during storage time.