• Korean Journal of Food Science and Technology
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• v.38 no.3
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• pp.400-407
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• 2006

Twenty six strains of lactic acid bacteria were isolated from Jeung-pyun batter, among which Tetragenococcus halophilus 1-12 showed highest dextransucrase activity at 36.95 DSU/mg, followed by T. halophilus 5-8 (36.87 DSU/mg protein), T. halophilus 2-12 (32.66 DSU/mg protein), T. halophilus 3-3 (31.43 DSU/mg protein), T. halophilus 3-1 (30.73 DSU/mg protein), T. halophilus 5-12 (29.43 DSU/mg protein), and Leuconostoc mesenteroides subsp mesenteroides 2-9 (28.5 DSU/mg protein). L. mesenteroides subsp mesenteroides 2-9, T. halophilus 1-12, and L. mesenteroides subsp dextranicum 5-13, were selected as starters (0.1, 0.5, and 1.0%) for Jeung-pyun manufacturing. Specific volume of Jeung-pyun added with 1.0% L. mesenteroides subsp dextranicum 5-13 was highest at 2.00, and 1.0% T. halophilus 1-12-added Jeung-pyun was lowest at 033. Cross-sectional observation of Jeung-pyun showed Jeung-pyun added with 0.5% L. mesenteroides subsp mesenteroides 2-9 was uniformly formed. Number of air holes of Jeung-pyun increased with increasing amount of added T. halophilus 1-12. Increasing addition of L. mesenteroides subsp dextranicum 5-13 resulted in more uniform air holes and volumes. Hardness, gumminess, and chewiness of Jeung-pyun added with 0.5 and 2.0% L. mesenteroides subsp dextranicum 5-13 decreased significantly in compasion to control groups. Jeung-pyun added with 0.5% L. mesenteroides subsp dextranicum 5-13 showed excelIent overall sensory desirability ranking of 8.500.

• Korean Journal of Agricultural Science
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• v.16 no.2
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• pp.225-238
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• 1989

These studies were conducted to investigate the extraction, purification and characterization of oriental pear (Niitaka. Pyrus pyrifolia Nak.) protease, and the results obtained were as follows: 1. Oriental pear protease was effectively extracted by the method of homogenizing pear pulp with 0.7 volume of 0.1M-sodium phosphate buffer, pH 6.5 containing 5mM-cysteine, 40mM-2-mercaptoethanol and 2mM-EDTA at 10,000 rpm for 5 min. 2. The protease was purified by ammonium sulfate fractionation, Sephadex G-100 filtration and DEAE-Sephadex A-50 column chromatography, and the purified enzyme gave a single protein band on polyacrylamide gel electrophoresis. 3. The specific activity of purified enzyme was 29.65 unit/mg protein and the yield was 7.22%. 4. The moecular weight of the protease was estimated to be about 51,000 by SDS-polyacrylamide gel electrophoresis, and the enzyme had Km value of 54.5 mg/ml for casein. 5. The purified enzyme had a maximum activity at pH 6.0 and $50^{\circ}C$, and was stable from pH 5.5-6.5 and at temperatures below $50^{\circ}C$ 6. Casein was a better substrate for this protease compared to hemoglobin. 7. The enzyme activity was markedly inhibited by p-chloromercuribenzoic acid and heavy metal salts such as $HgCl_2$ and $MnSO_4$ also considerably inhibited the enzyme activity.

• Journal of the Korean Wood Science and Technology
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• v.8 no.1
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• pp.13-21
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• 1980

This experiment was carried out to investigate the effect of heating periods on the physical and mechanical properties of maple (Acer mono Max.) by oven heating and heating in water at 100$^{\circ}C$ for 0, 2, 4, and 6 days respectively. The results obtained are summarized as follows: 1. The green volume specific gravity due to oven heating decreased from 6 days of exposure, and that, due to heating in water decreased from 4 days of exposure. 2. The radial shrinkage due to oven heating decreased from 2 days of exposure, but that due to heating in water increased from 6 days of exposure. The tangential shrinkage due to oven heating decreased from 2 days of exposure, but that due to heating in water increased from 2 days of exposure. 3. The amount of water absorption due to oven heating decreased from 2 days of exposure, but that due to heating in water increased from 4 days of exposure. 4. The compressive strength pararelled to grain due to oven heating increased till 4 days of exposure but decreased from 6 days, and that due to heating in water decreased from 2 days of exposure. 5. The shearing strength pararelled to grain due to oven heating increased till 2 days of exposure, but decreased from 4 days of exposure, and that due to heating in water decreased from 4 days of exposure. 6. The bending strength due to oven heating increased till 4 days of exposure but decreased from 6 days, and that due to heating in water decreased from 6 days of exposure. The impact bending absorbed energy due to oven heating decreased from 4 days of exposure, and that due to hearing in water decreased from 2 days of exposure.

• Journal of Navigation and Port Research
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• v.28 no.1
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• pp.59-67
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• 2004

As the environment for international logistics varies according to the globalization in world economy, world-class seaports are struggling for the position as strongholds in their own block. As a new government begins its own era in Korea, they are positively implementing their strategies at the level of government for making the Korean Peninsula the logistics centre in North-eastern Asia, marking the most of its geographic advantage. As one of those strategies, it plans to foster a specific area as an international logistics base camp in Northeast Asia by activating its logistics industry through inducing multinational logistics enterprises. In reality, however, in order for Busan seaport, the late-comer, to induce investment from the world-class multinational companies, a considerably large volume of investment should be given from both central and local governments. Accordingly, the objective of this study is to assess its competitiveness and to suggest an activation plan for BSDFA(Busan Seaport Duty-Free Area), based upon the results of on-the-spot interviews in China and Japan. The survey for the respondent's preference by way of Conjoint Analysis indicated that Investment procedures and limitations get the highest 36.2％ preference, so the most critical strategy to be considered for attracting enterprises into DFA(Duty-Free Area) is to solve the problems related to the investment procedures and limitations. The simulation analysis results for market share showed that UAE has the highest preference and BSDFA the lowest preference among the five countries. However, when the levels of investment procedures and limitations and production costare upgraded, the competitiveness of BSDFA was elevated next to that of UAE among the 5 countries. Thus, in order for BSDFA to obtain competitiveness, it is implied that production cost level as well as investment procedures and limitations level, should be lowered so that it could meet companies' demand.

• Economic and Environmental Geology
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• v.41 no.3
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• pp.299-314
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• 2008

The NE-trending Honam shear zone is a broad, dextral strike-slip fault zone between the southern margin of the Okcheon Belt and the Precambrian Yeongnam Massif in South Korea and is parallel to the trend of Sinian deformation that is conspicuous in Far East Asia. In this paper, we report geochemical and isotopic(Sr and Nd) data of mylonitic quartz-muscovite Precambrian gneisses and surrounding foliated hornblende-biotite granitoids near the Myeongho area in the Yecheon Shear Zone, a representative segment of the Honam Shear Zone. Foliated hornblende-biotite granitoids commonly plot in the granodiorite field($SiO_2=61.9-67.1\;wt%$ and $Na_2O+K_2O=5.21-6.99\;wt%$) on $SiO_2$ vs. $Na_2O+K_2O$ discrimination diagram, whereas quartz-muscovite Precambrian orthogneisses plot in the granite field. The foliated hornblende-biotite granitoids are mostly calcic and calc-alkalic and are dominantly magnesian in a modified alkali-lime index(MALI) and Fe# [$=FeO_{total}(FeO_{total}+MgO)$] versus $SiO_2$ diagrams, which correspond with geochemical characteristics of Cordilleran Mesozoic batholiths. The foliated hornblende-biotite granitoids have molar ratios of $Al_2O_3/(CaO+Na_2O+K_2O)$ ranging from 0.89 to 1.10 and are metaluminous to weakly peraluminous, indicating I type. In contrast, Paleoproterozoic orthogneisses have peraluminous compositions, with molar ratios of $Al_2O_3/(CaO+Na_2O+K_2O)$ ranging from 1.11 to 1.22. On trace element spider diagrams normalized to the primitive mantle, the large ion lithophile element(LILE) enrichments(Rb, Ba, Th and U) and negative Ta-Nb-P-Ti anomalies of foliated hornblende-biotite granitoids and mylonitized quartz-muscovite gneisses in the Yecheon Shear Zone are features common to subduction-related granitoids and are also found in granitoids from a crustal source derived from the arc crust of active continental margin. ${\varepsilon}_{Nd}(T)$ and initial Sr-ratio ratios of foliated hornblende-biotite granitoids with suggest the involvement of upper crust-derived melts in granitoid petrogenesis. Foliated hornblende-biotite granitoids in the study area, together with the Yeongju Batholith, show not changing contents of specific elements(Ti, P, Zr, V and Y) from shear zone to the area near the shear zone. These results suggest that no volume changes and geochemical alterations in fluid-rich foliated hornblende-biotite granitoids may occur during deformation, which mass transfer by fluid flow into the shear zone is equal to the mass transfer out of the shear zone.

• Korean journal of food and cookery science
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• v.14 no.4
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• pp.394-399
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• 1998

The juice of garlic (Euichun variety) was extracted and concentrated by heating at 90$^{\circ}C$, by using a rotary vacuum evaporator at 45$^{\circ}C$, or by freezing at -50$^{\circ}C$ until the volume was reduced to 70% of the original's. The concentrated garlic juice was packed into 15 ml test tubes wrapped with aluminum foil and kept at 4$^{\circ}C$ or 25$^{\circ}C$ for 60 days. Changes of browning, microbiological and sensory characteristics of the concentrated garlic juices were monitored every 10 days. The specific gravity and viscosity of the prepared juices decreased in the juices concentrated at 90$^{\circ}C$, 45$^{\circ}C$ and -50$^{\circ}C$ in order. Browning of the concentrated garlic juices was slower during the storage at 4$^{\circ}C$ than at 25$^{\circ}C$. Browning occurred rapidly in the juice concentrated at 45$^{\circ}C$ during the storage, especially at 25$^{\circ}C$. The numbers of mesophilic and psychrotrophic bacteria in the juices did not increase significantly during the storage, which means the garlic juices had good shelf-life. The CFUs/ml of garlic juice concentrated at 90$^{\circ}C$ were lower about 1 to 2 log cycles than those in other concentrated juices. The juice concentrated at 90$^{\circ}C$ showed the weakest garlic odor and the strongest cooked odor among the juices. The juice concentrated at -50$^{\circ}C$ had the freshest odor, especially stored at 4$^{\circ}C$, but the juice concentrated at 90$^{\circ}C$ had lowest score in fresh odor. Brown color was dark in the juice concentrated at 45$^{\circ}C$ and green color of all the juices did not change significantly during the storage.

• Journal of Animal Science and Technology
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• v.50 no.4
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• pp.561-572
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• 2008

Responses of real-time control parameters, such as ORP, DO and pH, to the conditions of biological animal wastewater treatment process were examined to evaluate the stability of real-time control using each parameter. Also an optimum index for supplemental carbon source addition based on NOx-N level was determined under a consideration of denitrification rate by endogenous respiration of microorganism and residual organic matter in liquor. Experiment was performed with lab-scale sequencing batch reactor(SBR) and working volume of the process was 45L. The distinctive nitrogen break point(NBP) on ORP-and DO-time profiles, which mean the termination of nitrification, started disappearing with the maintenance of low NH4-N loading rate. Also the NBP on ORP-and DO-time profiles was no longer observed when high NOx-N was loaded into the reactor, and the sensitivity of ORP became dull with the increase of NOx-N level. However, the distinctive NBP was constantly occurred on pH(mV)-time profile, maintaining unique profile patterns. This stable occurrence of NBP on pH(mV)-time profile was lasted even at very high NOx-N:NH4-N ratio(over 80:1) in reactor, and the specific point could be easily detected by tracking moving slope change(MSC) of the curve. Revelation of NBP on pH(mV)-time profile and recognition of the realtime control point using MSC were stable at a condition of over 300mg/L NOx-N level in reactor. The occurrence of distinctive NBP was persistent on pH(mV)-time profile even at a level of 10,000mg/L STOC(soluble total organic carbon) and the recognition of NBP was feasible by tracing MSC, but that point on ORP and DO-time profiles began to disappear with the increase of STOC level in reactor. The denitrfication rate by endogenous respiration and residual organic matter was about 0.4mg/L.hr., and it was found that 0.83 would be accepted as an index for supplemental carbon source addition when 0.1 of safety factor was applied.

• Journal of Science and Technology Studies
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• v.8 no.1
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• pp.97-129
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• 2008

We are living in the time of high probability of technological risk due to increased rate of technology development and diffusion of new technologies. Resolving uncertainties, the basic attribution of risk, by accumulating knowledge over the risk factors of certain technology is critical to management of technological risk. In many cases of technological risks, high uncertainty of knowledge is commonly mentioned reason for public controversies on risk management. However, the type of technological risk with low social agreement and low uncertainty of knowledge, the main reason for public controversy is absence of social agreement. Public debates on the risks of mobile phones electromagnetic fields(EMF) to human health comes under this category. The knowledge uncertainty on human health effect of mobile phones EMF has been lowered increasingly by accumulating enormous volume of knowledge though scientists have not reached a final conclusion whether it pose a risk to the physical and mental health of the general population or not. In contrast with civil organizations calling for precautionary approach based regulation, the mobile phone industry is cling to the position of no-regulation-needed by arguing no clear evidence to prove health risks of mobile phone EMF has found. In Korea, government set exposure standards based on a measurement called the 'specific absorption rate'(SAR) and require the mobile phone industry to open SAR information to the public by their own decision. From the view of pro-regulation side based on precautionary approach, technology risk managament of mobile phones EMF in Korea is highly limited and formalized one with limited measuring of SAR on head part only and problematic self-regulated opening of information about SAR to the public. As far as the government keeps having priority on protecting interest of mobile phone industry over precautionary regulation of mobile phones EMF, the disagreement between civil organizations and the government will not resolved. The risk of mobile phones EMF to human health have high probability of being underestimated in the rate and damage of risk than objectively estimated ones due to familiarity of mobile phone technology. And this can be the cause of destructive social dispute or devastating disaster. To prevent such disastrous results, technology risk management, which integrating the goals of safety with economic growth in public policy and designing and promoting risk communication, is required.

• Clean Technology
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• v.26 no.2
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• pp.102-108
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• 2020

In recent years, packed column has been widely used in separation processes, such as absorption, desorption, distillation, and extraction, in the petrochemical, fine chemistry, and environmental industries. Packed column is used as a contacting facility for gas-liquid and liquid-liquid systems filled with random packed materials in the column. Packed column has various advantages such as low pressure drop, economical efficiency, thermally sensitive liquids, easy repairing restoration, and noxious gas treatment. The performance of a packed column is highly dependent on the maintenance of good gas and liquid distribution throughout a packed bed; thus, this is an important consideration in a design of packed column. In this study, hydraulic pressure drop, hold-up as a function of liquid load, and mass transfer in the air, air/water, and air-NH₃/water systems were studied to find the geometrical characteristic for raschig super-ring experiment dry pressure drop. Based on the results, design factors and operating conditions to handle noxious gases were obtained. The dry pressure drop of the random packing raschig super-ring was linearly increased as a function of gas capacity factor with various liquid loads in the Air/Water system. This result is lower than that of 35 mm Pall-ring, which is most commonly used in the industrial field. Also, it can be found that the hydraulic pressure drop of raschig super-ring is consistently increased by gas capacity factor with various liquid loads. When gas capacity factor with various liquid loads is increased from 1.855 to 2.323 kg^-1/2 m^-1/2 S^-1, hydraulic pressure drop increases around 17%. Finally, the liquid hold-up related to packing volume, which is a parameter of specific liquid load depending on gas capacity factor, shows consistent increase by around 3.84 kg^-1/2 m^-1/2 S^-1 of the gas capacity factor. However, liquid hold-up significantly increases above it.

• The Journal of Korean Society for Radiation Therapy
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• v.26 no.1
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• pp.59-67
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• 2014

Purpose : This study aims to evaluate 3D dosimetric impact for MIP image and each phase image in stereotactic body radiotherapy (SBRT) for lung cancer using volumetric modulated arc therapy (VMAT). Materials and Methods : For each of 5 patients with non-small-cell pulmonary tumors, a respiration-correlated four-dimensional computed tomography (4DCT) study was performed. We obtain ten 3D CT images corresponding to phases of a breathing cycle. Treatment plans were generated using MIP CT image and each phases 3D CT. We performed the dose verification of the TPS with use of the Ion chamber and COMPASS. The dose distribution that were 3D reconstructed using MIP CT image compared with dose distribution on the corresponding phase of the 4D CT data. Results : Gamma evaluation was performed to evaluate the accuracy of dose delivery for MIP CT data and 4D CT data of 5 patients. The average percentage of points passing the gamma criteria of 2 mm/2% about 99%. The average Homogeneity Index difference between MIP and each 3D data of patient dose was 0.03~0.04. The average difference between PTV maximum dose was 3.30 cGy, The average different Spinal Coad dose was 3.30 cGy, The average of difference with $V_{20}$, $V_{10}$, $V_5$ of Lung was -0.04%~2.32%. The average Homogeneity Index difference between MIP and each phase 3d data of all patient was -0.03~0.03. The average PTV maximum dose difference was minimum for 10% phase and maximum for 70% phase. The average Spain cord maximum dose difference was minimum for 0% phase and maximum for 50% phase. The average difference of $V_{20}$, $V_{10}$, $V_5$ of Lung show bo certain trend. Conclusion : There is no tendency of dose difference between MIP with 3D CT data of each phase. But there are appreciable difference for specific phase. It is need to study about patient group which has similar tumor location and breathing motion. Then we compare with dose distribution for each phase 3D image data or MIP image data. we will determine appropriate image data for treatment plan.