• Journal of Korean Society of Environmental Engineers
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• v.22 no.3
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• pp.485-494
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• 2000

According to the worldwide interest in controlling $CO_2$ which contributes to green house effect. new techniques of reducing $CO_2$ are under development. We have developed new technique for reducing $CO_2$. In low $CO_2$ concentration. the chemical absorption method is useful. In this study. the kinetics of the reaction between $CO_2$ and the sterically hindered amine solution with piperazine. have been investigated from measurements of the rate of absorption of $CO_2$ in the stirred vessel that has a horizontal liquid-gas interface, in the temperature range $30{\sim}70^{\circ}C$. The experiments were carried out in the range 10.130~20.260 kPa of partial pressure of $CO_2$, and in aqueous $2.0kmol/m^3$ AMP solution with $0{\sim}0.4kmol/m^3$ piperazine The experimental results are as follows: 1) The absorption rate of $CO_2$ into aqueous AMP + piperazine solution is gett ng faster than that of aqueous AMP absorbents with temperature. Because the activation energy of piperazine 57.147 kJ/mol is higher than that of AMP 41.7kJ/mol. therefore the effect of piperazine on absorption rate increases with temperature. 2) Compared with aqueous AMP solution. the absorption rate of $CO_2$ into AMP + piperazine solution increases from 6.33% at $30^{\circ}C$ to 12% at $70^{\circ}C$, so AMP + piperazine solution is thought to be a better than AMP solution, 3) The reaction rate constants of piprazine in aqueous AMP solution with $CO_2$ have been determined as 217.21, 420.46, 707.00 and $3162.167m^3/kmol{\cdot}s$ respectively at 30, 40, 50 and $70^{\circ}C$ but these results are higher than those of Xu which were 186.7. 367.32. 693.01. $2207.65m^3/kmol{\cdot}s$ at 30, 40, 55, $70^{\circ}C$in aqueous MDEA solution. So the regression analysis of the data has led to the following equation In $k_p$ =28.324-6934.7/T.

• Journal of Nutrition and Health
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• v.42 no.1
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• pp.38-47
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• 2009

The purpose of the study was to develop an eating habit checklist for screening elementary school children at risk of inadequate micronutrient intake. Eating habits, food intake, and anthropometric data were collected from 142 children (80 boys and 62 girls) in the $4^{th}$ to $6^{th}$ grades of elementary schools. Percentage of Recommended Intakes (RI) and Mean Adequacy Ratio (MAR) of six micronutrients; vitamin A, riboflavin, vitamin C, calcium, iron, zinc, and the number of nutrients the children consumed below EAR among the six nutrients were used as indices to detect the risk of inadequate micronutrient intake. Pearson correlation coefficients were calculated between eating habit scores and inadequate micronutrient intake indices in order to select questions included in the checklist. Meal frequency, enough time for breakfast, regularity of dinner, appetite, eating frequencies of Kimchi, milk, fruits and beans showed significant correlations with indices of inadequate micronutrient intake. Stepwise regression analysis was performed to give each item a different weight by prediction strength. To determine the cut-off point of the test score, sensitivity, specificity, and positive predictive values were calculated. The 8-item checklist with test results from 0 to 12 points was developed, and those with equal or higher than 6 points were diagnosed as high-risk group of inadequate micronutrient intake, and those with 4 or 5 points were diagnosed as moderate-risk group. Among our subjects 14.1% was diagnosed as high-risk group, and 30.3% as moderate-risk group. The proportions of the subjects who consumed below EAR of all micronutrients but vitamin C were highest in the high-risk group, and there were significant differences in the proportions of the subjects with intake below EAR of all micronutrients except vitamin B6 among the three groups. This checklist will provide a useful screening tool to identify children at risk of inadequate micronutrient intake.

• Journal of Distribution Science
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• v.15 no.5
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• pp.75-83
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• 2017

Purpose - With the rise of the fourth industrial revolution, it has converged with the existing industrial revolution to give shape to increased accessibility of knowledge and information. As a result, it has become easier for scholars to actively persue and compile research in various fields. This current study aims to focus and assess the current standing of KODISA: the Journal of Distribution Science (JDS), International Journal of Industrial Distribution & Business(IJIDB), the East Asian Journal of Business Management (EAJBM), the Journal of Asian Finance, Economics and Business (JAFEB) in a rapidly evolving era. Novel strategies for creating the future vision of KODISA 2020 will also be examined. Research design, data, and methodology - The current research will analyze published journals of KODISA in order to offer a vision for the KODISA 2020 future. In part 1, this paper will observe the current address of the KODISA journal and its overview of past achievements. Next, part 2 will discuss the activities that will be needed for journals of KODISA, JDS, IJIDB, EAJBM, JAFEB to branch out internationally and significant journals will be statistically analyzed in part 3. The last part 4 will offer strategies for the continued growth of KODISA and visions for KODISA 2020. Results - Among the KODISA publications, IJIDB was second, JDS was 23rd (in economic publications of 54 journals), and EAJBM was 22nd (out of 79 publications in management field journals). This shows the high quality of the KODISA publication journals. According to 2016 publication analysis, JDS, IJIDB, etc. each had 157 publications, 15 publications, 16 publications, and 28 publications. In the case of JDS, it showed an increase of 14% compared to last year. Additionally, JAFEB showed a significant increase of 68%. This shows that compared to other journals, it had a higher rate of paper submission. IJIDB and EAJBM did not show any significant increases. In JDS, it showed many studies related to the distribution, management of distribution, and consumer behavior. In order to increase the status of the KODISA journal to a SCI status, many more international conferences will open to increase its international recognition levels. Second, the systematic functions of the journal will be developed further to increase its stability. Third, future graduate schools will open to foster future potential leaders in this field and build a platform for innovators and leaders. Conclusions - In KODISA, JDS was first published in 1999, and has been registered in SCOPUS February 2017. Other sister publications within the KODISA are preparing for SCOPUS registration as well. KODISA journals will prepare to be an innovative journal for 2020 and the future beyond.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.3
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• pp.303-309
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• 1999

Mass mortality of the Manila clam, Ruditapes philippinarum has been reported all along the west and south coast of Korea for the past several years. As a pathogenic agent, Perkinsus sp., an endoparasitic protozoan has been identified in this study and believed to be responsible for the mass mortalities. Prevalence and infection intensity of Perkinsus sp. was investigated from a Manila clam population inhabiting at Komsoe Bay in the west coast where mass mortality of the clam has been reported. A total of 142 Manila clam, 50 oyster, Crassostrea gigas, 10 ark shell, Scapharca broughtonii, and 5 predatory gastropada, Rapana venosa were examined for the presence and the quantity of Perkinsus sp. Ray's fluid thioglycollate medium method (FTM method) with modified Mackin's infection intensity scale and Choi's quantitative method were used in detecting and quantifying the parasite. All individuals of R. philippinarum examined in this study were infected with Perkinsus sp., indicating $100\%$ prevalence while none of the oysters and the gastropods exhibited the parasite. Six to ten individual hypnospores of Perkinsus sp. were counted from the ark shells. The number of hypnospores in the clam tissues varied from 16,667 to 4,091,667, with a mean number of 1,077,628. Average infection intensity according to Mackin's was 2.87, indicating a moderate infection. A negative correlation was observed between the number of Perkinsus sp. in the tissue and the condition index, a ratio tissue wet weight to shell cavity volume. The clam size and the infection intensity in terms of total number of parasites were positively correlated; the bigger clam, the heavier infection. Such high number of Perkinsus sp. counted in the clams could be enough to cause physiological disturbance of clams, such as retarded growth and reproduction. It is also believed that such a high infection leads mortality of the clam via continuous draining of the energy by metabolic activities and reproduction of the parasites. Correlation between the condition index and the infection intensity observed in this study supports this hypothesis.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.3
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• pp.265-272
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• 2002

Spatial distribution of Phytoplankton Pigment Concentration (PPC) and Sea Surface Temperature (SST) around the East Korean Warm Current (EKWC) was described, using both Coastal Zone Color Scanner (CZCS) images and Advanced Very High Resolution Radiometer (AVHRR) images in May, 1980. Water mass in this region can be classified into five categories in the horizontal profile of PPC and SST, nLw (normalized water-leaving radiance) images: (1) coastal cold water region associated with concentrations of dissolved organic material or yellow colored substances and suspended sediments, (2) cold water region of thermal frontal occurred by a combination of phytoplankton absorption and suspended materials, (3) warm water overlay region by the phytoplankton absorption than the suspended materials; (4) warm water region occurred by the low phytoplankton absorption, and (5) offshore region occurred by the high phytoplankton absorption. In particular, the highest PPC (>2.0 mg/m^3) area appeared in the CZCS and AVHRR images with a band shaped distribution of the thermal front and ocean color front region, which is located the coastal cold waters alonB western thermal front of the warm streamer of the EKWC. In this region, the highest PPC occurred by a combination of the high absorption of the phytoplankton (443 nm) and highest reflectance of suspended materials (550 nm). Another high PPC ($\simeq$$6\;mg/m^3$) appeared in the warm water overlay region inside warm streamer. High phytoplankton pigment concentration of this region was corresponding to the short wavelength of 443 nm, which represented phytoplankton absorption of the CZCS image.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.5
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• pp.485-492
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• 1986

This study was designed to compare the inhibitory effects of algae components such as alginic acid and chlorella extract with the red ginseng saponin and garlic components such as alliin and scordinin on obesity. These components supplemented to basic diet were fed ad libitum to Sprague Dawley rats for 4 weeks, and the inhibitory effects on obesity were evaluated by measuring body weight gain and feed efficiency, the contents of glucose and cholesterol in serum, lipase activity in serum, lipid contents in liver and adipose tissue around epididymis and ovarium, and Lee index, etc. Among the inhibitory effects of these components on obesity, Na-alginate($71\%$) was the most effective (p<0.01), and the others were effective (p<0.001) in the order of scordinin ($76\%$) = chlorella ($76\%$)> alliin ($86\%$) for body weight gain, but Na-alginate ($68\%$) was the most effective, followed by alliin ($79\%$) for feed efficiency (p<0.001). In the inhibitory effects on lipid accumultion in liver and adipose tissue, Na-alginate ($84\%$) among these components was the most effective (p<0.001) in liver, but Na-alginate ($54\%$) was the most effective (p<0.001), followed by alliin ($64\%$), and followed by scordinin ($66\%$) in adipose tissues around epididymis and ovarium (p<0.001). The inhibitory effect on obesity evaluated by Lee index was observed in Na-alginate ($91\%$) only (0.001). The decreasing effects of lipid content in liver by these components were effective in the order of alliin ($40\%$)> saponin ($58\%$)> Na-alginate($62\%$)> chlorella ($64\%$)> scordinin ($74\%$) (p<0.001). G lucose contents in serum were significantly decreased in cases of Na-alginate ($67\%$), saponin ($73\%$), scordinin ($74\%$) and alliin ($83\%$), and cholesterol contents in serum were significantly decreased in cases of Na-alginate ($82\%$), chlorella ($86\%$) and saponin ($89\%$) (p<0.001). The increasing effect of lipase activity in serum was effective in cases of Na-alginate ($109\%$) and saponin ($104\%$), while garlic components such as alliin and scordinin, and chlorella were decreased. It is proved that the inhibitory effect of alginic acid which is the major component of brown algae on obesity was more effective than those of ginseng and garlic components such as saponin, alliin and scordinin.

• Journal of the Korean Institute of Landscape Architecture
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• v.41 no.5
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• pp.78-90
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• 2013

The purpose of this study was to analyze the types and characteristics of public complaints caused by the landscape architecture projects in the case of apartment complex. Furthermore, its purpose was also to propose as the basis data for the minimization of complaints in the course of future landscape architecture projects. To analyze and categorize the apartment complex civil complaints, we collected basic and case study data from LH Corporation, SH Corporation and GICO from 2009 to 2012. We also categorized 672 landscape complaints to 73 categories and conducted a survey from residents and landscape architecture. This Survey is to use IPA can collect character(public-private), handling of civil affair(easy-hard) and analyze typical characters and difference of civil complaint awareness between landscape architecture and residents. First, we were categorized 73 civil complaints by type in 5 categories such as park, green space and street trees, pedestrian road, facilities, and others. Second, the most common landscape complaints appear in green spaces, street trees, facilities, pedestrian roads and park orders. Third, results of the analysis conducted for each item which are publicity and measures the ease. 'Facilities', 'landscape and greenery', 'pedestrian road' and others were commonly appears from residents and professional awareness of the complaints. However, complaints of park appear different awareness between landscape architecture and residents. Fourth, 35 from 73 civil complaints(47.9%) are having high publicity and easy to measure, 25 civil complaints(34.2%) has analyzed to individual and difficult to measure so about the these complaints need to check from the design step so that it is necessary to minimize the problem of additional expense by civil complaints burden and decrease the confidence of residence problem were considered.

• Microbiology and Biotechnology Letters
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• v.48 no.3
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• pp.344-357
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• 2020

Strain improvement and bioprocess development were undertaken to enhance hyaluronic acid(HA) production by Streptococcus zooepidemicus cells. Using a high-yielding mutant strain, statistical medium optimization was carried out in shake flask cultures, resulting in 52% increase in HA production (5.38 g/l) at the optimal medium composition relative to the parallel control cultures. For sufficient supply of dissolved oxygen (DO), which turned out to be crucial for enhanced production of HA, agitation system and speed were intensively investigated in 5 L bioreactor cultures. Increase in oxygen mass transfer coefficient (k_La) through increment of agitation speed (rpm) and 35% expansion of diameter of the newly-designed impellers showed significantly positive effects on HA production. By installing an expanded Rushton-turbine impeller for efficient break-down of sparged air, and an extended marine impeller above the Rushton-turbine impeller for efficient mixing of the air-born viscous fermentation broth, maximum amount of HA (9.79 g/l) was obtained at 450 rpm, 1.8 times higher level than that of the corresponding flask culture. Subsequently, the possibility of bioprocess scale-up to a 50 L bioreactor was investigated. Despite almost identical maximum HA production (9.11 vs 9.25 g/l), the average HA volumetric productivity (r_p) of the 50 L culture turned out only 74% compared to the corresponding 5 L culture during the exponential phase, possibly caused by shear damages imposed on the producing cells at the high stirring in the 50 L culture. The scale-up process could be successfully achieved if a scale-up criterion of constant oxygen mass transfer coefficient (k_La) is applied to the 50 L pilot-scale bioreactor system.

• The Korean Journal of Physiology
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• v.22 no.2
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• pp.189-206
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• 1988

The effects of ouabain on the contractile and electrical activities were investigated in the isolated preparations of guinea-pig taenia coli, and compared with those of vanadate. Spontaneous contractions were recorded with force transducer, and electrical activites were measured by use of suction electrode, or single sucrose-gap technique. The contractions were induced by the electrical stimulation for 5 seconds every 1 minute with alternating current (60 Hz, 3.0 V/cm) through the platinum electrodes located in parallel with the long axis of the preparation. All experiments were performed in tris-buffered Tyrode solution which was aerated with $100%{\;}O_2$ and kept at $35^{\circ}C$. The results obtained were as follows: 1) Responses of spontaneous contractions to ouabain were concentration-dependent; $10^{-7}M$ ouabain caused a rise of basal tone. Above the concentration of $10^{-6}M$ ouabain, an initial increase followed by a decrease in tension was observed. 2) A continuous spike discharge was induced by the administration of $10^{-7}M$ ouabain. Above $10^{-6}M$ ouabain, a transient initial increase followed by a decrease in spike frequency and amplitude was produced, and finally membrane potential was sustained at a certain level without a spike discharge. 3) The characteristic response to $10^{-7}M$ ouabain was not blocked by the pretreatment with $10^{-7}M$ atropine. 4) The electrically induced contractions were completely suppressed at the concentration of $2{\times}10^{-7}M$ ouabain. These contractions were blocked more rapidly in paralled with the increase in ouabain concentration. 5) Effects of vanadate on the spontaneous activities were quite different from those of ouabain; $10^{-6}M$ vanadate increased the amplitude of contractions and $10^{-5}M$ vanadate increased slightly both amplitude and frequency of spontaneous contractions. $10^{-4}M$ vanadate showed irregular phasic contractions superimposed on the increased basal tone. 6) $10^{-5}M$ vanadate depolarized the membrane potential and shortened the interval between the bursts of spike discharge, whereas $10^{-4}M$ vanadate induced continuous spike discharge with membrane depolarization. 7) Vanadate caused a characteristic inhibitory response to the contractions induced by electrical stimulation; An initial rapid inhibition of tension development and then gradual recovery to a certain level. From the above results, the following conclusions could be made: 1) The rise of basal tone at $10^{-7}M$ ouabain is due to continuous spike discharge without a silent period. The continuous spike discharge is likely to be associated with a slight membrane depolarization caused by the blockage of Na pump. 2) The biphasic response induced by above $10^{-6}M$ ouabain seems to occur by the different mechanisms. The initial increase in tension is associated with depolarization along with an increase in spike frquency, whereas the subsequent relaxation occurs through a non-electrical mechanism. 3) The characteristic response to $10^{-7}M$ ouabain is resulted not from the action on intrinsic nerve terminal, but from its direct action on the membrane of smooth muscle cells. 4) The phasic contractions superimposed on the increased basal tone at the concentration of $10^{-4}M$ vanadate is resulted from the continuous spike discharge with membrane depolarization, of which mechanism remains unknown. 5) The inhibitory action of ouabain on the electrically induced contractions suggests that the increasein intracellular Na in some way inhibits the electrically induced $Ca^{2+}$ influx. The mechanism of vanadate action on the induced contractions remains unknown.

• Proceedings of the Materials Research Society of Korea Conference
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• 2011.05a
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• pp.5-5
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• 2011

The research and development of hybrid electric vehicle (HEV), plug-in hybrid electric vehicle (PHEV) and electric vehicle (EV) are intensified due to the energy crisis and environmental concerns. In order to meet the challenging requirements of powering HEV, PHEV and EV, the current lithium battery technology needs to be significantly improved in terms of the cost, safety, power and energy density, as well as the calendar and cycle life. One new technology being developed is the utilization of composite cathode by mixing two different types of insertion compounds [e.g., spinel $LiMn_2O_4$ and layered $LiMO_2$ (M=Ni, Co, and Mn)]. Recently, some studies on mixing two different types of cathode materials to make a composite cathode have been reported, which were aimed at reducing cost and improving self-discharge. Numata et al. reported that when stored in a sealed can together with electrolyte at $80^{\circ}C$ for 10 days, the concentrations of both HF and $Mn^{2+}$ were lower in the can containing $LiMn_2O_4$ blended with $LiNi_{0.8}Co_{0.2}O_2$ than that containing $LiMn_2O_4$ only. That reports clearly showed that this blending technique can prevent the decline in capacity caused by cycling or storage at elevated temperatures. However, not much work has been reported on the charge-discharge characteristics and related structural phase transitions for these composite cathodes. In this presentation, we will report our in situ x-ray diffraction studies on this mixed composite cathode material during charge-discharge cycling. The mixed cathodes were incorporated into in situ XRD cells with a Li foil anode, a Celgard separator, and a 1M $LiPF_6$ electrolyte in a 1 : 1 EC : DMC solvent (LP 30 from EM Industries, Inc.). For in situ XRD cell, Mylar windows were used as has been described in detail elsewhere. All of these in situ XRD spectra were collected on beam line X18A at National Synchrotron Light Source (NSLS) at Brookhaven National Laboratory using two different detectors. One is a conventional scintillation detector with data collection at 0.02 degree in two theta angle for each step. The other is a wide angle position sensitive detector (PSD). The wavelengths used were 1.1950 ${\AA}$ for the scintillation detector and 0.9999 A for the PSD. The newly installed PSD at beam line X18A of NSLS can collect XRD patterns as short as a few minutes covering $90^{\circ}$ of two theta angles simultaneously with good signal to noise ratio. It significantly reduced the data collection time for each scan, giving us a great advantage in studying the phase transition in real time. The two theta angles of all the XRD spectra presented in this paper have been recalculated and converted to corresponding angles for ${\lambda}=1.54\;{\AA}$, which is the wavelength of conventional x-ray tube source with Cu-$k{\alpha}$ radiation, for easy comparison with data in other literatures. The structural changes of the composite cathode made by mixing spinel $LiMn_2O_4$ and layered $Li-Ni_{1/3}Co_{1/3}Mn_{1/3}O_2$ in 1 : 1 wt% in both Li-half and Li-ion cells during charge/discharge are studied by in situ XRD. During the first charge up to ~5.2 V vs. $Li/Li^+$, the in situ XRD spectra for the composite cathode in the Li-half cell track the structural changes of each component. At the early stage of charge, the lithium extraction takes place in the $LiNi_{1/3}Co_{1/3}Mn_{1/3}O_2$ component only. When the cell voltage reaches at ~4.0 V vs. $Li/Li^+$, lithium extraction from the spinel $LiMn_2O_4$ component starts and becomes the major contributor for the cell capacity due to the higher rate capability of $LiMn_2O_4$. When the voltage passed 4.3 V, the major structural changes are from the $LiNi_{1/3}Co_{1/3}Mn_{1/3}O_2$ component, while the $LiMn_2O_4$ component is almost unchanged. In the Li-ion cell using a MCMB anode and a composite cathode cycled between 2.5 V and 4.2 V, the structural changes are dominated by the spinel $LiMn_2O_4$ component, with much less changes in the layered $LiNi_{1/3}Co_{1/3}Mn_{1/3}O_2$ component, comparing with the Li-half cell results. These results give us valuable information about the structural changes relating to the contributions of each individual component to the cell capacity at certain charge/discharge state, which are helpful in designing and optimizing the composite cathode using spinel- and layered-type materials for Li-ion battery research. More detailed discussion will be presented at the meeting.