• Economic and Environmental Geology
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• v.24 no.2
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• pp.131-150
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• 1991

The Weolseong diatreme was temporally and spatially related to the intrusion of the Gadaeri granite, and was -mineralized by meteoric aqueous fluids. In the Nokdong As-Zn deposit, pyrite, aresenopyrite and sphalerite are the most abundant sulfide minerals. They are associated with minor amount of magnetite, pyrrhotite, chalcopyrite and cassiterite, and trace amounts of Pb-Sb-Bi-Ag sulphosalts. The AsZn ore probably occurred at about $350^{\circ}C$ according to fluid inclusion and compositional data estimated from the arsenic content of arsenopyrite and iron content of sphalerite intergrown with pyrrhotite + chalcopyrite + cubanite. Heating studies of fluid inclusions in quartz indicate a temperature range between 180 and $360^{\circ}C$, and freezing data indicate a salinity range from 0.8 to 4.1 eq.wt % NaCl. The coexisting assemblage pyrite + pyrrhotite + arsenopyrite suggests that $H_2S$ was the dominate reduced sulfur species, and defines fluid parameter thus: $10^{-34.5}$ < ${\alpha}_{S_2}$ < $10^{-33}$, $10^{-11}$ < $f_{S_2}$ < $10^{-8}$, -2.4 < ${\alpha}_{S_2}$ < -1.6 atm and pH= 5.2 (sericte stable) at $300^{\circ}C$. The sulfur isotope values ranged from 1.8 to 5.5% and indicate that the sulfur in the sulfides is of magmatic in origin. The carbon isotope values range from -7.8 to -11.6%, and the oxygen isotope values from the carbonates in mineralized wall rock range from 2 to 11.4%. The oxygen isotope compositions of water coexisting with calcite require an input of meteoric water. The geochemical data indicate that the ore-forming fluid probably was generated by a variety of mechanisms, including deep circulation of meteoric water driven by magmatic heat, with possible input of magniatic water and ore component.

• Journal of Sensor Science and Technology
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• v.7 no.3
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• pp.179-187
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• 1998

A neutral particle energy analyzer, which has the carbon stripping foil and the $90^{\circ}$ cylindrical electrostatic deflection plate, was designed and constructed for measuring of ion temperature in plasma. The energy calibration and energy resolution were studied in detail for a hydrogen ion at the $0.5{\sim}3.0\;keV$ energy using a duoplasmatron ion source. An energy of hydrogen ion to the deflection plate voltage at the peak ion count rate could be fitted by the expression $E_{o}(keV)$=3.83V(kV). The measured energy resolution, which was about 2 % at the energy of 3.0 keV and 9 % at the energy of 0.5keV, was better for the increased hydrogen ion energy. For the charge exchanged hydrogen atom due to the carbon stripping foil, the energy calibration, energy loss and resolution were measured to the $0.5{\sim}2.0{\mu}g/cm^{2}$ thickness of the carbon stripping foil. An energy of the charge exchanged hydrogen atom as a function of the deflection plate voltage and carbon foil thickness could be fitted by the expression $E_{o}(keV)=(0.53d+4.4){\cdot}V(kV)$. The energy loss was $0.23{\sim}0.89\;keV $ to the $0.5{\sim}2.0{\mu}g/cm^{2}$ carbon foil thickness and the $0.5{\sim}3.0\;keV$ energy of the incident neutral hydrogen atom, it could be fitted by the expression ${\Delta}E=(0.12d+0.27){\cdot}{E_{o}}^{1/2}(keV)$. The measured energy resolution for the neutral hydrogen atom, which was between 7 % and 35 % in this experiment region, was increased for the increasing neutral hydrogen atom energy and the decreasing carbon stripping foil thickness.

• Journal of Food Hygiene and Safety
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• v.30 no.2
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• pp.159-165
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• 2015

The aim of this study was to investigate microbiological contamination levels in the manufacturing company of ginseng products (white and red ginseng). Firstly, the contamination level for ginseng and each stage ginseng were 1.8~4.9 log CFU/g (total bacteria), 1.2~3.0 log CFU/g (coliform), 0.8~4.1 log CFU/g (fungi). However, only Bacillus cereus among pathogenic bacteria was detected from a few sample. The contamination of total bacteria tended to decrease as ginseng was being processing. Therefore, that of finished products (white and red ginseng) showed the lowest contamination level among each stage ginseng sample. That of fungi decreased steadily, although the contamination of fungi has tended to increase right after ginseng was steamed. Secondly, the contamination level for working tools and facilities were $1.7{\sim}4.7log\;CFU/cm^2$ (total bacteria), $0.4{\sim}4.0log\;CFU/cm^2$ (coliform), $0.9{\sim}4.2log\;CFU/cm^2$ (fungi). Especially, washing and peeling machines were higher contamination level. Finally, the contamination level of worker who washed and steamed ginseng was higher than worker who shaped, sorted and stored ginseng. Also, Staphylococus aureus was detected at 0.2~0.7 log CFU/hand on some wokers' hands. These results showed proper heating condition (temperature and time) and tidy manufacturing facility are the most important to avoid developing any microbiological problem of Ginseng Products.

• Horticultural Science & Technology
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• v.32 no.3
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• pp.346-352
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• 2014

This research was carried out to investigate the effect of supplemental lighting on stable productivity of paprika (Capsicum annuum L.) during low radiation period of winter season. The supplemental lighting sources used in this research were high pressure sodium (HPS) and lighting emitting plasma (LEP). Photosynthetic photon flux density (PPFD) emitted from both lamps decreased as vertical distance from lamp increased. The PPFD of LEP lamps were twice more than that of the HPS lamp per unit distance, but the rate of decreased PPFD of t he LEP per unit distance was higher than that of HPS lamp. And different degrees of PPFD between HPS and LEP lamps by horizontal distance had a smaller degree of difference than by vertical distance at the 100 cm away point. As daily average PPFD measured at the top of the plant under the supplemental lighting during January, the supplemental lighting significantly increased radiation. Radiation of HPS and LEP lighting was 137% and 315% higher than control (without supplemental lighting = sunlight). Air temperature in the top of the plant was not significant different among treatments. HPS and LEP lighting had no effect on increase of flower settings. Leaf length and width with LEP lighting was the longest, photosynthetic was higher than those of other treatments. Supplemental lighting treatments significant increased fruit length and diameter. Especially LEP lighting treatment had a greater effect on fruit length and diameter. In conclusion, LEP lighting treatment during low radiation period greatly affected growth and production of paprika. Further research will be required for the suitable application of LEP lighting in paprika production.

• Korean Journal of Ecology and Environment
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• v.49 no.1
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• pp.31-41
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• 2016

Deutzia paniculata is an endemic species to the Korean Peninsula. Despite of importance for conservation, the population structure and habitat characteristics of D. paniculata have not been determined yet. We analyzed the ecological characteristics of the species based on the literature review and field survey. Field survey was conducted on May to October 2014 during which 11 quadrats of size $15{\times}15m$ were studied in six regions. Each of the quadrats were further divided into $5{\times}5m$ small quadrats and population characteristics were recorded. The population and habitat characteristics were analyzed, including species abundance (density and coverage), demographic attributes (flowering rates and fruiting plants), vegetation (structure, species composition), light availability (transmitted light and canopy openness) and soil characteristics (temperature and humidity). We found that D. paniculata mainly distributed in Gyeongsangdo (including Taebaek in Gangwondo) along a broad elevational range of 290~959 m (mean: 493 m) above sea level. In preferred habitat the species grows within the slope range of $7^{\circ}$ and $35^{\circ}$ with the average of $16^{\circ}$. D. paniculata was generally distributed on talus deposits and low adjacent slopes. The average number of individual plants per small quadrat was 12.5 with the mean density $0.5stems\;m^{-2}$. The vegetative reproduction was frequent in D. paniculata and mean flowering rate was as low as 15%. Altogether 138 taxa were found in whole observation area with the dominant tree species mainly spring ephemerals, such as Cornus controversa (importance value: 25.5%) and Fraxinus rhynchophylla (importance value: 15.8%). Although, C. controversa usually grows on steep slopes and F. rhynchophylla mostly distributed at high-altitudes, however, both species distributed in disturbed environments and among talus deposits. Thus based on our results, we concluded that D. paniculata is a disturbance-prone species, primarily existing in habitats subjected to natural disturbances, such as floods. The species occurs less at anthropogenically disturbed sites, thus there is no apparent threat to the populations and habitat of D. paniculata.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.37 no.6
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• pp.487-498
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• 1992

To study the effects of different nursing methods and transplanting on the growth of rice plant (Oriza sativa L.) in southern region of Korea, Kumo-byeo, Palgong-byeo and Dongjinbyeo were transplanted from April 20 to July 20 at an interval of 15 days with 8 days old seedling (infant seedling) and 25 days old box-seedling for machine transplanting, and 45 days old conventional seedling. Threshold transplanting date in southern region of Korea were June 26 for 8 days old seedling, July 1 for 25 days old seedling and] July 11 for 45 days old seedling for Kumo-byeo, and June 21, June 30, July 10 for Palgong-byeo, June 10, June 24, July 5 for Dongjin-byeo, respectively. Yield has no uniform tendency according to the transplanting date. However, yield were greater in the order of 8 days old seedling >25 days old seedling> 45 days old seedling in Kuma-byeo and 25 days old seedling (equation omitted)8 days old seedling (equation omitted)45 days old seedling in Palgong-byeo, 45 days old seedling(equation omitted)25 days old seedling(equation omitted) 8 days old seedling in Dongjin-byeo. The optimum accumulated air temperature during yield productive stage around heading (40 days from 10 days before heading to 30 days after heading) for high yield were 1,003$^{\circ}C$ for 8 days old seedling, 1,014$^{\circ}C$ for 25 days old seedling and 1,027$^{\circ}C$ for 45 days old seedling in Kumo-byeo. And they were 1,018$^{\circ}C$, 1,015$^{\circ}C$, 1,086$^{\circ}C$ in Palgong-byeo and 998$^{\circ}C$, 984$^{\circ}C$, 949$^{\circ}C$ in Dongjin-byeo, respectively. Earlier transplanting with 8 days old seedling showed higher ratio of broken rice and green kerneled rice in Kuma-byeo, and late transplanting after July 5 showed significant high rate of green kerneled rice. Palgong-byeo and Dongjin-byeo also showed high rate of green kerneled rice at transplanting after July 5.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.62 no.3
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• pp.184-192
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• 2017

Rice flours from five rice (Oryza sativa L.) varieties with different amylose content were prepared by both wet and dry milling processes. The moisture content of wet-milled rice flours (WMR) was approximately three-times higher than that of dry-milled rice flours (DMR). Water absorption index (WAI), water solubility index (WSI), and swelling power (SP) increased in proportion to temperature. The WAI, WSI and SP values of DMR were higher than those of WMR. Baeokchal (BOC), which is a waxy rice cultivar, had a significantly high WSI value. Pasting properties of DMR, except for the BOC cultivar, resulted in an increase in peak, trough, final, and setback viscosities. The levels of resistant starch in four cultivars, except for Dodamssal (DDS), were under 1%, irrespective of the milling process, whereas the resistant starch contents of DMR and WMR in DDS were 9.18% and 6.27%, respectively. In vitro digestibility of WMR was higher than that of DMR, and the estimated glycemic index of the rice flour varieties ranged from 57.6 to 81.3. Damaged starch content of WMR was less than that of DMR; in addition, a negative correlation was observed between the amylose and damaged starch contents of WMR. These results suggest that the properties of rice flour vary depending on the milling method and flour variety, and could be a reference for selecting the appropriate processing method.

• Journal of Animal Science and Technology
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• v.45 no.5
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• pp.825-834
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• 2003

Chicken thigh from a retail market were used as experimental samples. Some chicken samples of raw state were packaged with PVDC at an aerobic and vacuum condition. The other samples were cooked until core temperature arrived at 70$^{\circ}C$ and then packaged immediately in the same way of raw samples. After samples were irradiated by electron beam at 6 kGy, they were stored in a refrigerator. Identification and quantity of cholesterol oxides were made at 0 and 7 days of storage, respectively. During the early stage of storage, 7$\beta$-hydroxycholesterol, $\alpha$,$\beta$-epoxide, cholestanetriol and 7-ketocholesterol were produced from the raw meat samples, and the production of these chemicals were significantly higher(P〈0.05) from the samples with aerobic packaging than those with vacuum packaging. With storage time, 7$\alpha$-hydroxycholesterol, 6-ketocholesterol and some other chemicals, which were not found during the early stage of storage, were found. Also, the formation of these chemicals were significantly increased(P〈0.05) with storage time. Cholesterol and lipid oxidation products of cooked meat after irradiation and irradiated meat after cooking were significantly increased(P〈0.05) with storage time for all treatments, and vacuum packaging results in showed significantly lower value(P〈0.05) than aerobic packaging. Summarizing the aforementioned results, it was found that the formation of cholesterol and lipid oxides and lipid oxidation was more easily affected by packaging condition than irradiation.

• Journal of Animal Science and Technology
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• v.51 no.4
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• pp.337-342
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• 2009

The feasibility of reutilization of magnesium ammonium phosphate (MAP) or struvite slurry recovered from the process through microwave irradiation was studied in this experiment. For this purpose, 4 different operations were performed with or without Mg source addition and different levels of MAP recycled in a batch reactor. Dissolution rate of MAP, ${NH_4}^+$ elimination pattern and physicochemical changes of MAP during microwave irradiation were also studied. The result showed that only 33% orthophosphate ($PO_4-P$) and 27% $NH_4-N$ removal occurred without adding any external Mg source (run A), whereas 87% $PO_4-P$ and 40% $NH_4-N$ removed when 1.0 M ratio of $MgCl_2$ (run B) was added based on $PO_4-P$ in influent. Although the addition of 1.0 molar ratio of microwave irradiated MAP (Run C) removed lower $PO_4-P$ and $NH_4-N$ than 1.0 M $MgCl_2$ (run B), $PO_4-P$ removal was double when compared with no Mg addition (run A). Addition of half MAP and half $MgCl_2$ (run D) showed the similar removal efficiency (88% $PO_4-P$ and 35% $NH_4-N$) with sole $MgCl_2$ addition (run B). Based on these results, the reutilization of MAP irradiated by microwave would be a feasible way to enhance the removal efficiencies of N and P, as well as curtail the Mg chemical usage. Track study showed that $NH_4-N$ gradually increased at initial stage of microwave irradiation of MAP, and then started eliminating from liquor as temperature increased over $45^{\circ}C$. Dissolution rate of ${PO_4}^{-3}$ during microwave irradiation was proportional to the initial MAP concentration, having $0.0091x^{0.6373}$ mg/sec. It was found from the scanning electron microscope (SEM) study that physical structure of MAP crystal started breaking down into small cube granules within very short time by electromagnetic vibration force during microwave irradiation and then gradually melted down into solution.

• Journal of Bio-Environment Control
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• v.9 no.3
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• pp.161-165
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• 2000

Spectroradiometric light transmittance from 300 to 1,100nm in the greenhouse covered with the CEM BIO polyethylene film was greater than that in the greenhouse covered with polyethylene film (control). As a whole, solar radiation transmittance into greenhouse was a half level, due to shades caused by double layer covering, frame and equipment. Net radiation energy emitted throughout surface of the greenhouse covered with CEM BIO polyethylene film was 5,424.5W.m$^{-2}$ , which was lower by 2.9% as compared to that of the greenhouse covered with polyethylene film. Photosynthetically active radiation from 400 to 700nm of the greenhouse covered with CEM BIO polyethylene film was 3,861.2W.m$^{-2}$ , which was higher by 3.8% as compared to hat of the greenhouse covered with polyethylene film. Accumulated minimum air temperature from Oct. 7, 1997 to Oct. 16, 1997 of the greenhouse covered with CEM BIO polyethylene film was 100.5$^{\circ}C$, which was higher by 2.5$^{\circ}C$ as compared to that of the greenhouse covered with polyethylene film. As results, height, stem diameter, leaf count, leaf area, fresh weight and dry weight of green pepper plants and canopy production structure measured at 30 days after transplanting were enhanced. Mean fruit weight n the greenhouse covered with CEM BIO polyethylene film was 11.28 g and 1.25 g greater as compared to that in the greenhouse covered with polyethylene film, due to increased fruit diameter and flesh thickness. Percent marketable fruits produced in the greenhouse covered with CEM BIO polyethylene film were 96.1%, and was greater by 2.7% thant that of the greenhouse covered with polyethylnee film due to decreased infection, sterility, severe curve and twisted fruits. The green pepper yield of the greenhouse covered with CEM BIO polyethylene film from Nov. 19, 1997 to Feb. 3, 1998 was greater by 974 kg per hectare than that of the greenhouse covered with polyethylene film, but the total fruit had no difference.