• Journal of the Korean institute of surface engineering
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• v.42 no.1
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• pp.8-12
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• 2009

Electronic structures and chemical bonding of Li-intercalated $LiTiS_2$ and $LiTiO_2$ were investigated by using discrete variational $X{\alpha}$ method as a first-principles molecular-orbital method. ${\alpha}-NaFeO_2$ structure is the equilibrium structure for $LiCoO_2$, which is widely used as a commercial cathode material for lithium secondary battery. The study especially focused on the charge state of Li ions and the magnitude of covalency around Li ions. The average voltage of lithium intercalation was calculated using pseudopotential method and the average intercalation voltage of $LiTiO_2$ was higher than that of $LiTiS_2$. It can be explained by the differences in Mulliken charge of lithium and the bond overlap population between the intercalated Li ions and anions in $LiTiO_2$ as well as $LiTiS_2$. The Mulliken charge, which means the ionicity of Li atom, was approximately 0.12 in $LiTiS_2$ and the bond overlap population (BOP) indicating the covalency between Ti and S was about 0.339. One the other hands, the Mulliken charge of lithium was about 0.79, which means that Li is fully ionized. The BOP, the covalency between Ti and O, was 0.181 in $LiTiO_2$. Because of high ionicity of Li and the weak covalency between Ti and the nearest anion, $LiTiO_2$ has a higher intercalation voltage than that of $LiTiS_2$.

• Journal of the Korean association of regional geographers
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• v.5 no.1
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• pp.121-135
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• 1999

This study investigated the location conditions, spatial linkage structures, and firm specific problems of small firms of the Greater Cincinnati metropolitan area by sectors and by areal distribution. The major locational advantages were closeness to customers and suppliers followed by accessibility to inter-state highways. These results were supported by spatial linkage structures in which within-region linkages occupied a greater portions of linkage, showing the importance of small firms in the regional economy. The linkage patterns showed distance decay effect with high elasticity. While there were no significant differences of locational conditions and spatial linkage structures of small firms between core and peripheral area, a slight difference was identified among sectors. Chemical related manufacturing firms show different locational conditions and spatial linkage structure with weak within-local linkages. The main locational disadvantages were lack of qualified labor, undesirable neighborhood, heavy tax, and space shortage. Considering the biggest problems such as lack of qualified labor, difficulties in sales/marketing, low accessibility to financial resource, and technological inability, the inter-related cooperative business networks among firms and regional institutions, consulting companies, chamber of commerce, and universities are needed to stimulate regional economic development and survival of small firms.

• Economic and Environmental Geology
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• v.36 no.5
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• pp.349-356
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• 2003

As industrial activities are growing, pollutants found in the contaminated land are getting diverse. Some contaminated areas are subject to mixed wastes containing both organic and inorganic wastes such as hydrocarbon and heavy metals. This study concerns with the influence of the degradation of organic pollutants on the coexisting heavy metals, expecially for As. As mainly exists as two different oxidation state; As(III) and As(V) and the conversion between the two chemical forms may be induced by organic degradation in the soil contaminated by mixed wastes. We operated microcosm in an anaerobic chamber for 60 days, using sandy loam. The soils in the microcosm are artificially contaminated both by tetradecane and As, with different combination of As(III) and As(V); As(III):As(V) 1:1, As(III) only and As(V) only. Although not systematic, ratio of As(III)/As(Total) increase slightly at the later stage of experiment. Considering complicated geochemical reactions involving oxidation/reduction of organic materials, Mn/Fe oxides and As, the findings in the study seem to indicate the degradation of the organics is connected with the As speciation. That is to say, the As(V) can be reduced to As(III) either by direct or indirect influence induced by the organic degradation. Although Fe and Mn are good oxidising agent for the oxidation of As(III) to As(V), organic degradation may have suppressed reductive dissolution of the Fe and Mn oxides, causing the organic pollutants to retard the oxidation of As(III) to As(V) until the organic degradation ceases. The possible influence of organic degradation on the As speciation implies that the As in mixed wastes may be have elevated toxicity and mobility by partial conversion from As(V) to As(III).

• Korean Journal of Environmental Agriculture
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• v.33 no.3
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• pp.164-168
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• 2014

BACKGROUND: Increase in application of liquid pig manure(LPM) in agriculture as nutritional source has become a social issue due to its influence on water quality. Also, proper application methods have not been developed with respect to indigenous properties of LPM and soil physical properties. Therefore, we conducted this experiment to observe the infiltration characteristics and distribution of dissolved organic compounds of LPM in soils having different soil textures. METHODS AND RESULTS: To do this experiment, we collected three different soils and LPM. We analyzed the physical and chemical properties of both soils and LPM to determine the dilution ratios of LPM. The LPM diluted to 4 different ratios with distilled water was applied to the top of soil column. Infiltration rates were observed by time and depth until the amount of effluent collected from the bottom of the soil columns were stabilized while maintaining the hydraulic head 3 cm above the soil column. The results showed that infiltration rates increased with increasing dilution ratios in the order of sandy, loamy sand, and sandy loam. The time required to reach steady state was increased with decreasing sand contents clay. CONCLUSION: The size and amount of the dissolved organic compounds in LPM that can determine the efficiency as fertilizer and environmental problems as nonpoint pollution source in water quality have not been investigated with respect to behavior and transport of them in soil. Therefore, it requires further research how we can properly apply LPM as valuable fertilizer substitute for inorganic fertilizers.

• Asian Journal of Atmospheric Environment
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• v.9 no.2
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• pp.114-127
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• 2015

In the Mexico City Metropolitan Area (MCMA), ozone ($O_3$) concentration is still higher than in other urban areas in developed countries. In order to reveal the current state of photochemical air pollution and to provide data for validation of chemical transport models, vertical profiles of meteorological parameters and ozone concentrations were measured by ozonesonde in two field campaigns: the first one, during the change of season from wet to dry-cold (November 2011) and the second during the dry-warm season (March 2012). Unlike previous similar field campaigns, ozonesonde was launched twice daily. The observation data were used to analyze the production and distribution of ozone in the convective boundary layer. The observation days covered a wide range of meteorological conditions, and various profiles were obtained. The evolution of the mixing layer (ML) height was analyzed, revealing that ML evolution was faster during daytime in March 2012 than in November 2011. On a day in November 2011, the early-morning strong wind and the resulting vertical mixing was observed to have brought the high-ozone-concentration air-mass to the ground and caused relatively high surface ozone concentration in the morning. The amount of produced ozone in the MCMA was estimated by taking the difference between the two profiles on each day. In addition to the well-known positive correlation between daily maximum temperature and ozone production, effect of the ML height and wind stagnation was identified for a day in March 2012 when the maximum ground-level ozone concentration was observed during the two field campaigns. The relatively low ventilation coefficient in the morning and the relatively high value in the afternoon on this day implied efficient accumulation of the $O_3$ precursors and rapid production of $O_3$ in the ML.

• Journal of Energy Engineering
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• v.25 no.3
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• pp.73-82
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• 2016

The energy consumption efficiency in a variety of operational test mode was considered for domestic gas boiler below 70 kW. The energy efficiency test carried out in the experimental conditions similar to the actual operation status was analyzed and compared with the current Korean efficiency test method. Four types of test modes for each boiler(Non-condensing and condensing boiler) were carried out in the condition of laboratory mode(full load, steady state) and actual operating mode. Futhermore divided into two operational status for each of these, it was applied by maximum gas consumption and consumer sales conditions. Test equipment has the function referred to gas boiler standards, such as KS or European standard EN. The equipment should be continuously measured and record the measuring factors which are the flow volume of gas and water, laboratory temperature, water flow volume for heating, return water volume after heating and quantity of the exhaust gases(CO, NO, $NO_2$). The experimental results were found that non-condensing boiler efficiency of laboratory mode is about 10% higher than that of actual mode. In case of condensing boiler, the efficiency of laboratory condition is about 20% higher than that of the actual using conditions. I suggest that the government will gradually take the efficiency test method considering the actual conditions.

• Journal of Environmental Impact Assessment
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• v.27 no.1
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• pp.56-72
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• 2018

North Korea has been in ecologically deficit state since 1966, despite of lack of energy and food resources. Trends of the Biocapacity (BC), the Ecological Footprint (EF), and the Ecological Deficit (ED) of North Korea were shown and five factors influencing on the Overshoot Rate (OSR) which is the ratio of the BC and the EF in North Korea was analyzed in this study. The five factors consist of two factors affecting to the EF and three factors affecting to the BC in North Korea. Two of the five factors are affecting to the EF those are population, the EF per capita (EFPC) which indicates the individual environmental consumption intensity, and three are affecting to the BC those are the land area, the yield factor, and the value multiplying the equivalence factor and the intertemporal yield factor. The EF has contributed more than the BC to the OSR. From 1966 to mid-1990s, the EFPC was the most contributing factor at about 60%, and after mid-1990s, population at about 40~60%. Contribution ratio of land area and the yield factor have increased after mid-1990s up to 15% and 18%, respectively. The BC of cropland which has decreased due to a decrease in productivity. In order to reduce the ED of North Korea, improvement of productivity of cropland and restoration of forest. Forest area has decreased significantly since 1990 in NK. And ways to solve the food shortage problem which influences on decrease of both productivity of cropland and forest area.

• Archives of Plastic Surgery
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• v.32 no.1
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• pp.85-92
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• 2005

Botulinum toxin type A is widely used for anti-wrinkling therapy, and correction of the square face. The toxin ultimately prevent the release of membrane-bound acetylcholine at the neuromuscular junction of striated muscles and thus produce chemical denervation and paralysis of the muscles. Our purpose of study is to know if application of botulinum toxin type A on calf reduction is effective, how much dosage is effective, and what are the possible complications. We reviewed data of 30 consecutive patients subjected to calf reduction in Dong-A University Hospital from February 2003 to April 2003. We injected normal saline 2cc on both calves region in 15 control group patients, and the other patients was divided 3 group. Group 1, Group 2, Group 3 was injected 50U, 100U, 150U botulinum toxin A on each calf region and followed up for 6 month. Maximal circumference of calf was not changed in the control group but an average of 0.7 cm reduction was noted in group 1, average 1.34 cm(right calf) and 1.26cm(left calf) in group 2, average 1.44cm(right calf) and 1.58cm(left calf) in group 3. Maximal area of calf was not changed in the control group but average reduction of 12.5%(right calf) and 12.7%(left calf) was obtained in group 1, average 19.4% (right calf) and 19.9%(left calf) in group 2, average 24.8%(right calf) and 21.07%(left calf) in group 3, as measured on CAT scan. Total fat amount and fat amount in the lower extremity was no change in all the groups, but lean body mass was decreased average 1.27%(right calf) and 1.15%(left calf) in group 1, average 3.47%(right calf) and 2.98%(left calf) in group 2, average 3.58%(right calf) and 3.95%(left calf) in group 3. Photography of the preoperative and postoperative 6 month state revealed higher satisfaction in Group 2, 3 compared to Group 1. Use of botulinum toxin type A in calf reduction is a very simple, safe, non-invasive method and effective in terms of calf contouring rather than reduction of calf circumference.

• Korean journal of food and cookery science
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• v.28 no.6
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• pp.789-796
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• 2012

This study attempted to investigate the characteristics of Superjami, which had a high C3G (cyandin-3-glucoside) content by comparing it with common rice (Ilpum) and black rice (Heougjinju, Suwon 415) for their components and physio-chemical characteristics. There were no significant differences in the water content, however there were significant differences in crude protein and crude fat in the order of Ilpum < Superjami < Heougjinju. As for the morphological characteristics of grains, it had been learned that Superjami was heavier and longer than the common rice, moreover Superjami had bigger seeds. As for the hardness of grains, the longer the time of steeping, the more decreased their hardness was at large. In the case of color, they showed significant differences in all the L, a, and b values of grains and flours. As a result of the experiment of pigment elution after steeping of the rice flours at $20^{\circ}C$ and $40^{\circ}C$, the longer the time steeping, the more increased the pigment elution became. The values are bigger with Heougjinju and Superjami than with Ilpum. As for the elution pH after rice steeping, the longer the time of steeping, the lower pH all the assays tended to have. As a result of the analysis of the total polyphenol contents of Ilpum, Heougjinju, and Superjami, it had turned out that the total polyphenol contents of Heougjinju and Superjami are 1.2 times as high as Ilpum, a common rice, and that Superjami is significantly higher than Heougjinju. As a result of the experiment of DPPH radical scavenging ability, there are significant differences among the assays in the order of Superjami > Heougjinju > Ilpum. Futher, it has turned out that Superjami has a higher DPPH radical scavenging ability than Heougjinju. Consequently, it can be stated that Superjami has a strong anti-oxidative ability. Thus, we should more precisely grasp the cooking characteristics of Superjami, which is in the state of brown rice, via comparing it with a common brown rice, and also provide opportunities to apply Superjamii to more foods by studying its starch characteristics in addition to its grain and flour properties.

• Fire Science and Engineering
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• v.26 no.3
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• pp.21-28
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• 2012

The objective of this study is to evaluate the prediction accuracy of FDS(Fire Dynamic Simulator) for the thermal and chemical characteristics of under-ventilated fire with unsteady fire growth in a semi-closed compartment. To this end, a standard doorway width of the full-scale ISO 9705 room was modified to 0.1 m and the flow rate of heptane fuel was increased linearly with time (until maximum 2.0 MW based on ideal heat release rate) using a spray nozzle located at the center of enclosure. To verify the capability of FDS, the predicted results were compared with a previous experimental data under the identical fire conditions. It was observed that with an appropriate grid system, the numerically predicted temperature and heat flux inside the compartment showed reasonable agreement with the experimental data. On the other hand, there were considerable limitations to predict accurately the unsteady behaviors of CO and $CO_2$ concentration under the condition of continuous fire growth. These results leaded to a discrepancy between the present evaluation of FDS and the previous evaluation conducted for steady-state under-ventilated fires. It was important to note that the prediction of transient CO production characteristics using FDS was approached carefully for the under-ventilated fire in a semi-closed compartment.