• Journal of the Society of Cosmetic Scientists of Korea
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• v.38 no.1
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• pp.15-31
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• 2012

In our previous studies, the antioxidant, anti-aging, and antibacterial activities of Persicaria hydropipier L. extract, and the moisturizing effect of cream containing P. hydropipier extract were investigated. In this study, the cellular protective effects of P. hydropipier extract and isoquercitrin, main component from P. hydropipier in $^1O_2$-induced photohemolysis of human erythrocytes and ultraviolet B (UVB)-exposed HaCaT cells were investigated. Liposomes such as ethosome and elastic liposome for enhanced transdermal delivery were prepared. Size, loading efficiency, stability, and cumulative permeated amounts of ethosomes and elastic liposomes were evaluated. P. hydropipier extract and isoquercitrin showed more prominent cellular protective effect than (+)-${\alpha}$-tocopherol, known as lipid antioxidant at $5{\mu}g/mL$. P. hydropipier extract didn't show any characteristics of cytotoxicity at $50{\mu}g/mL$. When HaCaT cells were exposed to a single large dose ($400mJ/cm^2$) of UVB, the extract protected the cells against UVB radiation in a concentration dependent manner ($12.5{\sim}50{\mu}g/mL$). Cell viability of HaCaT cells exposed to UVB $400mJ/cm^2$ was increased by treatment with P. hydropipier extract or isoquercitrin from 36 % (cell viability of positve control groups) to 90 % (cell viability of P. hydropipier extract or isoquercitrin- treated groups). The size of 0.04 % P. hydropiper extract loaded ethosomes was 173.0 nm and the loading efficiency was 55.58 %. 0.04 % P. hydropiper extract loaded ethosomes were stable with as monodisperse particles for 1 week. The ethosome exhibited more skin permeability than general liposome and ethanol solution. The optimal ratio of lipid to surfactant ($Tego^{(R)}$ care 450) of 0.1 % P. hydropiper extract loaded elastic liposomes was observed to be 95 : 5. Vesicle size of 0.1 % P. hydropiper extract loaded elastic liposome was 176.5 nm. The deformability index of the elastic liposome was 16.4. The loading efficiency was 68.8 %. The elastic liposome containing P. hydropiper extract showed more skin permeability than liposome without surfactant ($Tego^{(R)}$ care 450).

• Proceedings of the Korea Water Resources Association Conference
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• 2008.05a
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• pp.869-877
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• 2008

The purpose of this study is to investigate the trends and patterns of variou kind of water uses in a household by metering in Korea. Water use components are classified by toilet, washbowl, bathing, laundry, kitchen, etc. Flow meters are installed in 146 household selected by sampling in all around Korea. The data are gathered by web-based data collection system from the year 2002 to 2006, considering pre-investigated data such as occupation, revenue, family members, housing types, age, floor area, water saving devices, education, etc. Reliable data are selected by upper fence method for each observed water use component and statistical characteristics are estimated for each residential type to determine liter per capita per day. Estimated domestic per capita day show an indoor water use with the range from $150{\ell}pcd$ to $169{\ell}pcd$ for each housing type as the order of high rise apartment, multi-house, and single house. As the order of consuming amount among water use components, it is investigated that toilet($38.5{\ell}pcd$) is the first, and the second is laundry water($30.8{\ell}pcd$), the third is kitchen($28.4{\ell}pcd$), the fourth is bathtub($24.7{\ell}pcd$), the next is washbowl($15.4{\ell}pcd$). The results are compared with water uses in U.K. and U.S. As life style has been changed into western style, pattern of water use in Korea is tend to be similar with the U.S. water use pattern. Compared with the surveying results by Bradley, on 1985. Thirty liter of total use increased with the advancement of economic level, and a little change of water use pattern can be found. Especially, toilet water take almost half part of total water use and laundry water shows lowest as 11% in surveying at the year of 1985. But, this study shows that 39 liter, 28% of toilet water, has been decreased by the spread of saving devices and campaign. It is supposed that the spread large sized laundry machine make by-hand laundry has been decreased and water use increased. Unit water amount of each end-use in household can be applied to design factor for water and wastewater facilities, and it play a role as information in establishing water demand forecasting and conservation policy.

• Asia pacific journal of information systems
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• v.24 no.3
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• pp.255-279
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• 2014

It is not too much to say that smartphones have become an essential part of our lives due to their versatility. Nevertheless, they still have less overall capabilities than their desktop counterparts. Specifically, they have small screens and low resolutions, which make their applications difficult to have a usable interface. To account for these limitations, the interface of smartphone applications should be designed carefully and properly. Good interface design to any application is critical. However, a comprehensive information systems (IS) literature review found that there has been little research on the user interface design of smartphone applications. More specifically, there has been little empirical evidence and understanding about how metaphors, an imaginative way of describing objects and concepts, in the user interface of smartphone applications affect users' intention to use the applications. Thereby, the research goals of this study are to examine 1) the effects of the metaphors in the user interface of smartphone applications on the interaction between users and applications and 2) the effects of mediating variables including the interaction between users and applications, users' beliefs and attitudes, on users' intention to use the applications. A survey was conducted to collect data. University students and practitioners participated in the survey. A 24-item questionnaire was developed on a 5-point Likert-type scale. The measurement items were mostly adapted from the previous studies in the IS literature and modified to fit the context of this study. First, a principal component factor analysis was performed to explore the inter-relationships among a set of variables. The analysis showed that most of the items loaded quite strongly on the six components. The analysis also revealed the six components with eigenvalues exceeding 1, explaining a total of 70.7 per cent of the variance. The reliabilities of the items were also checked. Most Cronbach alpha values were above 0.8, so the scales were considered reliable. In sum, the results of the analysis support the decision to retain the six factors for further investigation. Next, the structural model was analyzed with AMOS structural equation modeling. The values of GFI, AGFI, NFI, TLI, CFI, and RMSEA were checked. The values showed that the research model considerably have a good fit in general. Next, the convergent and discriminant validities of all constructs were examined. The values for the standardized regression weights and critical ration (CR) indicated sufficient convergent validity for all constructs. In addition, the square root of the average variance extracted (AVE) of each construct was compared with its correlations with all other constructs. The results supported discriminant validity for all constructs. In sum, the results of analysis demonstrated adequate convergent and discriminant validities for all constructs. Finally, path coefficients between the variables were examined. Methphor was found to have an impact on interaction (${\beta}$ = .457, p = .000). There were also significant effects of the interaction on perceived usefulness (${\beta}$ = .273, p = .000) and ease of use (${\beta}$ = .405, p = .000). User attitude was significantly influenced by these two beliefs, perceived usefulness (${\beta}$ = .386, p = .000) and ease of use (${\beta}$ = .347, p = .000) respectively. Further, the results of analysis found that users' intention to use smartphone applications was significantly influenced by user attitude (${\beta}$ = .567, p = .000). Based upon the analyses, all hypotheses were supported. This study found that the metaphors used in the interface of smartphone applications affect not only the interaction between users and applications, but also users' intention to use the applications through the mediating variables, perceived usefulness and ease of use. These findings imply that if the metaphors used in the user interface of application are easy enough to understand for smartphone users, then the application can be perceived useful and easy to use, which in turn make users to have an intention to use the application. In conclusion, this study contributed not only to validate and extend Technology Acceptance Model (TAM) partially, but also to develop the construct of metaphor in smartphone settings. However, since a single empirical study cannot be enough to validate the findings, some limitations should be considered.

• Journal of Food Hygiene and Safety
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• v.26 no.2
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• pp.142-149
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• 2011

An isocratic high performance liquid chromatography (HPLC) method for routine analysis of deoxynivalenol in noodles was validated and estimated the measurement uncertainty. Noodles (dried noodle and ramyeon) were analyzed by HPLC-ultraviolet detection using immunoaffinity column for clean-up. The limits of detection (LOD) and quantification (LOQ) were 7.5 ${\mu}g$/kg and 18.8 ${\mu}g$/kg, respectively. The calibration curve showed a good linearity, with correlation coefficients $r^2$ of 0.9999 in the concentration range from 20 to 500 ${\mu}g$/kg. Recoveries and Repeatabilities expressed as coefficients of variation (CV) spiked with 200 and 500 ${\mu}g$/kg were $82{\pm}2.7%$ and $87{\pm}1.3%$% in dried noodle, and $97{\pm}1.6%$ and $91{\pm}12.0%$ in ramyeon, respectively. The uncertainty sources in measurement process were identified as sample weight, final volume, and sample concentration in extraction volume as well as components such as standard stock solution, working standard solution, 5 standard solutions, calibration curve, matrix, and instrument. Deoxynivalenol concentration and expanded uncertainty in two matrixes spiked with 200 ${\mu}g$/kg and 500 ${\mu}g$/kg were estimated to be $163.8{\pm}52.1$ and $435.2{\pm}91.6\;{\mu}g$/kg for dried noodle, and $194.3{\pm}33.0$ and $453.2{\pm}91.1\;{\mu}g$/kg for ramyeon using a coverage factor of two which gives a level of statistical confidence with approximately 95%. The most influential component among uncertainty sources was the recovery of matrix, followed by calibration curve.

• The Korean Journal of Mycology
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• v.23 no.2 s.73
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• pp.121-128
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• 1995

The characteristics of protein-bound polysaccharides (PBP) which were isolated and purified from the sawdust mycelia of Agrocybe cylindracea were investigated. The yield of crude protein-bound polysaccharides (Fr.CB) extracted with boiling water and precipitated with 95% ethanol, was 0.74% based on the original sawdust mycelia. The Fr.CB was purified by the membrane filtration, ion exchange chromatography and gel filtration. The Fr.B fraction of which the molecular weight is over 300 KDa, was isolated from the Fr.CB using membrane filtration, and the yield was 38.6% based on the Fr.CB. This result indicates that high molecular protein-bound polysaccharides are the dominent components of the Fr.CB. Two fractions (Fr.B-1, Fr.B-2) were also isolated from the Fr.B using ion exchange chromatography, and the yields were 17.3% (Fr.B-1) and 10.3% (Fr. B-2), respectively. The Fr.B-1 was concentrated and gel-filtrated, and the single peak, thought to be nearly pure protein-bound polysaccharides, was obtained. The yield of final fraction $(Fr.B-1-{\beta})$ was 42.5% based on the Fr.B-1. The molecular weight of $Fr.B-1-{\beta}$ was nearly 710 KDa. The monosaccharides' composition of $Fr.B-1-{\beta}$ was analized by HPLC, and glucose was the dominent component, and fucose and galactose were also detected. The result of amino acid analysis was that glutamic acid and analysis were detected to a significant level, and cysteine was not detected.

• Korean Journal of Agricultural Science
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• v.14 no.1
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• pp.1-15
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• 1987

This experiment was conducted to investigate the effect of nitrogen top-dressing and Jangyeopkong was planted under two different seeding time (single cropping-May 15, after barley cropping-June 18), four levels of nitrogen top-dressing (0, 3, 6, 9 kg/10a) and two times of nitrogen top-dressing (Hilling time, Flowering Time). The results obtained are summarized as follow: 1. The days to flowering and maturity were delayed a day longer in hilling times than flowering times of nitrogen top-dressing. 2. The number of nodes of main stem and length of internodes didn't show significance among treatments. But, the number of nodes of branches was much higher when the soybean was planted on May 15, and were higher hilling time than flowering time as the amount of nitrogen top-dressing increased. Especially, the number of nodes of branches was high when 6kg of nitrogen was applied during hilling time. 3. The fresh and dry weight of stem and leaves at 10, 25 and 40 days after flowering were increased by increasing the amount of nitrogen top-dressing. More apparent effect of nitrogen was attained high significant when nitrogen was applied at the time of hilling rather than flowering time. 4. The number and fresh weight of nodule, and dry weight were apparently decreased after barley and were decreased according to the increasing the amount of nitrogen top dressing. The degrees of decreasing was more apparent in the hilling time than in the flowering time. 5. The number of pods per plant, and number and weight of grain per plant were higher when the soybean was planted on May 15, the amount of top dressing increased and hilling time rather than flowering time. Especially, yield component were highest when 6kg of nitrogen was applied during hilling time. Also, the grain yield per 10a showed high significance among treatment, and were high when 6kg of nitrogen was applied during hilling time.

• Journal of Radiation Protection and Research
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• v.10 no.2
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• pp.96-108
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• 1985

A study for the assessment of natural environmental radiation exposure at a flat and open field of about $10,000m^2$ in area in CNU Daeduk campus has been carried out by means of gamma-ray scintillation spectrometry and thermoluminescence dosimetry for one year period of time from October 1984. The detectors used were 3'${\phi}{\times}$3' NaI(T1) and two different types of LiF TLD, namely, chip sealed in plastic sheet which tightly pressed on two open holes of a metal plate and Teflon disk. Three 24-hour cycles of in-situ spectrometry, and two 3-month and one 1-month cycles of field TL dosimetry were performed. All the spectra measured were converted into exposure rate by means of G(E) opertaion, and therefrom exposure rate due to terrestrial component of environmental radiation was figured out. Exposure rate determined by the spectrometry was, on average, $(10.54{\pm}2.96){\mu}R/hr$, and the rates of $(12.0{\pm}3.4){\mu}R/hr$ and $(11.0{\pm}3.6){\mu}R/hr$ were obtained from chip and disk TLD, respectively. Fluctuations in diurnal variation of the exposure rate measured by the spectrometry were noticeable sometime even in a single cycle of 24 hours. It is concluded that appropriately combined use of TLD with iu-sitn gamma-ray spectrometry system can give more accurate and precise measure of environmental radiation exposure, and further study for more adequate and sensitive TLD for environmental dosimetry, including improvement and elevation of accuracy in data assessment through inter-laboratory or international intercomparison is necessary.

• Korean Journal of Environmental Agriculture
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• v.6 no.2
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• pp.53-65
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• 1987

The study was performed to investigate the effect of gaseous emissions of sulfur dioxide and hydrogen fluoride on the growth of rice plants under stressed field conditions consisting of 88 industrial plants operating with 285 smoke stacks emitting pollutants. As for the relationship between yields and yield components it is believed that the panicles per hill is the single most important component affecting the rate of yield of the rice plant. Based on the standard partial regression coefficient analysis, panicles per hill has the largest contribution to yield and the average contribution of 54%. Other components such as spikelets per panicle, percent fertility and 1000 grain weight are also contributing factors to yield, although far less so. Fluorine content in the leaf appear to have more negative effect on panicles per hill, percent fertility and subsequent overall yield than does sulfur content in the leaf. It is constantly observed and interesting to note that fluorine and sulfur content in the leaf appears to have no effect on spikelets per panicle and 1000 grain weight. Reduction in yield seems to be affected mainly by panicles per hill which are, in turn, affected more by fluorine content in the leaf as demonstrated by the standard partial coefficient analysis. Regarding the prediction sum of the square of the regression equation, the lowest value was found when nine variables were used for the analysis. The variables taken into consideration were the monthly sulfur and fluorine content in the leaf as well as the monthly percent of leaf damage during the months of June, July and August. A significant correlation is found between the actual and predicted yields by the regression equations selected as a result of a prediction sum of the square analysis.

• Applied Biological Chemistry
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• v.16 no.1
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• pp.1-11
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• 1973

In order to obtain the basic informations on the production of single cell protein from ethanol, 145 yeast strains utilizing ethanol as a sole carbon source were isolated from 32 soil samples in Korea. A yeast strain showing the highest cell yield among the isolated strains was selected and identified. The optimum culture condition, utilization of other carbon sources and the cultural characteristics for the selected yeast, and the chemical analysis of the yeast cell composition, and utilization of ethanol by the selected yeast were investigated. All the culture was carried out in the shaking flasks. The results obtained were as follows: 1. The selected yeast strain was identified as Debaryomyces nicotianae-SNU 72. 2. The optimum composition of the medium for the selected yeast is : Ethanol 40 ml, Urea 0.5 g, Potassium phosphate (dibasic) 0.5 g, Ammoium phosphate (monobasic) 0.15 g, Magnesium sulfate 0.05 g, Calcium chloride 0.01g, Yeast extract 0.005 g, Tap water 1000 ml. 3. The optimum pH was 5.0-5.5, the optimum temperature $30-33^{\circ}C$ and the aerobic state was unimportant. 4. Utilization of methanol, n-propanol, iso-propanol, n-butanol, iso-butanol, tert-amyl alcohol and acetic acid by the selected yeast was very weak. So substitution of the subtrate was thought to be impossible. 5. Studies on the propagation of the yeast cells showed that the lag phase of the yeast cells lasted 16 hours, and the logarithmic growth phase extended 16 to 28 hours. The specific growth rate was about $0.19\;hr^{-1}$ and the doubling time was 3.6 hours during the logarithmic growth phase. 6. As the result of the chemical analysis of the dry yeast cells, the content rate of the crude protein was 55.19 %, the content of others was similar to the average content of the yeast component. 7. After 34 hours cultivation, under the optimum culture condition investigated, the dry cell yield against the amount of the added ethanol was 53.4 % (W/V%), the dry cell yield against the amount of the utilized ethanol was 73.6 % (W/V%), the evaporation rate of ethanol was about 19.1 %.

• Journal of Preventive Medicine and Public Health
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• v.26 no.2 s.42
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• pp.222-230
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• 1993

Industrial glues, known as 'Bonds' in Korea, contain many kinds of organic solvents, and glue sniffing of youths became one of the social problems in Korea. Mixed exposures to solvents by glue sniffing may induce chronic toxicities different from those by exposures to solvents of single component. To test effects of the glue sniffing on weight gain or central nervous system, two groups of 20 male Sprague-Dawley rats were exposed to air(control group) or vapors of the glues to narcotic status(exposed group), and weight check, tail flick test, hot plate test, rotarod treadmill test were done on the 14th,24th, 36th, 45th, 53rd, 86th, 102nd, 117th, 134th and 151st days after the first exposure. On the 188th day, their brains were excised and examined by a pathologist. Weight gain, controlled against time change, showed significant difference between the groups, but response times in tail flick test, hot plate tests, and rotarod treadmill test didn't. In pathological examination with blind method, no macroscopic or microscopic differences were found between the two groups. These results suggests that organic lesion in central nervous system may not ensue glue sniffing, but, before firm conclusion, more studies in various exposure conditions should be followed.