• Journal of the Korean earth science society
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• v.21 no.3
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• pp.287-301
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• 2000

In order to investigate the factors and processes affecting the vertical distributions of ozone, we analyzed the ozone profile data measured using ozonesonde from 1995 to 1997 at Pohang city, Korea. In the course of our study, we analyzed temporal and spatial distribution characteristics of ozone at four different heights: surface (100m), troposphere (10km), lower stratosphere (20km), and middle stratosphere (30km). Despite its proximity to a local, but major, industrial complex known as Pohang Iron and Steel Co. (POSCO), the concentrations of surface ozone in the study area were comparable to those typically observed from rural and/or unpolluted area. In addition, the findings of relative enhancement of ozone at this height, especially between spring and summer may be accounted for by the prevalence of photochemical reactions during that period of year. The temporal distribution patterns for both 10 and 20km heights were quite compatible despite large differences in their altitudes with such consistency as spring maxima and summer minima. Explanations for these phenomena may be sought by the mixed effects of various processes including: ozone transport across two heights, photochemical reaction, the formation of inversion layer, and so on. However, the temporal distribution pattern for the middle stratosphere (30km) was rather comparable to that of the surface. We also evaluated total ozone concentration of the study area using Brewer spectrophotometer. The total ozone concentration data were compared with those derived by combining the data representing stratospheric layers via Umkehr method. The results of correlation analysis showed that total ozone is negatively correlated with cloud cover but not with such parameter as UV-B. Based on our study, we conclude that areal characteristics of Pohang which represents a typical coastal area may be quite important in explaining the distribution patterns of ozone not only from surface but also from upper atmosphere.

• Reproductive and Developmental Biology
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• v.28 no.3
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• pp.167-172
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• 2004

This study was performed to examine the correlations among dog sperm viabilities evaluated by flow cytometry, by microscopic evaluation (ME), by carbo-xifluorescein diacetate and propidium iodide (CFDA/PI) and by hypoosmotic swelling (HOS) test. Semen were collected from 5 dogs ranging in age from 2 to 4 years. Each ejaculate was divided into 3 aliquots and different proportions of freeze-killed cells were added to each aliquot (1:0, 1:1 and 1:3). In the other experiment, semen was extended with Sweden extender containing 5% glycerol and equex STM paste, and frozen using liquid nitrogen vapor. Fresh and frozen-thawed dog sperm viability were assessed by flow cytometry using PI staining method. The accuracy of flow cytometry was evaluated by comparing with other classic assessments, microscopic evaluation, epifluorescence microscopic analysis using CFDA/PI, and HOS test. High correlations of sperm viabilities were found among flow cytometry, epifluorescence evaluation, HOS test (p<0.01) in fresh semen. Especially, sperm viability assessed by HOS test was highly correlated with viability by flow cytometry in all the ratios of live and dead spermatozoa, 1:0, 1:1 and 1:3 (p<0.01). The viability evaluated by ME were significantly correlated with that by flow cytometry in ratios of 1:0 and 1:3 (p<0.05) however, there was no significance in ratio of 1:1. The viability evaluated by C/p were highly correlated with that by flow cytometry in ratio of 1:0 and 1:1 (p<0.01) and significantly correlated in ratio of 1:3 (p<0.05). In frozen-thawed spermatozoa, the viability determined by HOS test was considerably correlated with that by flow cytometry (p<0.01). There was significant correlation between the viabilities by ME and by flow cytometry (p<0.05). But the viability evaluated by CFDA/PI was not correlated with viability by flow cytometry. The result from this study validate the use of flow cytometry as a precise method for assessing the viability of fresh and frozen-thawed dog spermatozoa.

• Clinical and Experimental Pediatrics
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• v.51 no.3
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• pp.286-292
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• 2008

Purpose : We performed EEG and PET on children with epilepsy concomitantly in order to evaluate the effects of epileptiform and non-epileptiform discharge of EEG on glucose metabolism. Methods : Seventy three children with epilepsy who had PET and EEG simultaneously were included in our study. The subjects were classified in two ways: (1) based on the frequency of epileptiform discharge and (2) the severity of non-epileptiform discharge. We evaluated the clinical aspects of their seizures, the severity of focal slow waves during the interictal period with the frequency of spikes or sharp waves in order to compare with the PET results. Results : The subjects were divided by the frequency of epileptiform discharge, with 13 in the no/rare group, 7 in the occasional group, and 53 children in the frequent group. The concordant rates with PET in each group were 0%, 42.9%, and 67.9%, respectively, showing high correlations with the frequency of epileptiform discharge (P<0.05, r=0.491). The subjects as divided by the severity of non-epileptiform discharge were 15 in the no group, 25 in the infrequent group, 17 in the intermediate group, and 16 in the continuous group. The concurrence rates with PET for each group were 13.3%, 52.0%, 64.7%, and 68.8%, respectively, also showing a high correlation with the severity of non-epileptiform discharge (P<0.05, r= 0.365). Conclusion : Epileptiform discharge and non-epileptiform discharge in EEG showed a certain association with hypometabolism in PET. We recommend EEG to reduce false lateralization and to localize lesions in cases of high frequency and severity.

• Journal of Korean Society of Forest Science
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• v.79 no.1
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• pp.56-70
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• 1990

Eighteen Korean white pine (P. koraiensis S. et Z.) families were tested in 3 different regions from age 5 to 9. Family and site were significant sources of variation for seedling survival and field growth, whereas the effects of family x site interaction ware relatively small as compared with the former sources of variation. Variance components estimated from the separate and combined sites indicated that the most variabilities were associated with individual trees within plot. Family ${\times}$ site interaction components as a percentage of family variance decreased sharply with age. Heritability estimates varied with testing site and tree age. Combined analyses, however, showed a moderate change in heritability with increasing tree ages, and demonstrated high and stable trends of estimates, particularly in family heritabilities of tree height ($h_F{^2}=0.789-0.798$). The gains estimated from combined analysis have expected maximum or near-maximum efficiencies at age 6 or 7. Given equal intensity of selection, mass selection showed the most efficient gains within and across the sites. However, for the differences between mass and combined selections are small, selection made on the combination of family and within-family would be more effective in improving genetic gains. Indirect selection method indicated that 5-and 6-years height were all good predictors of 9-year-old height with little loss of relative efficiency (less than 10%) as compared with direct family selection at age 9. Phenotypic and genetic correlations computed on the basis of family mean values of height and diameter have shown predominantly high, positive, and statistically significant (1% level) relationships between all tested pairs of traits, which indicates that family growth maintained statistically consistent trends with age. The best families are those that maintained a stable superiority overall sites and ages in growth performance, therefore, it can be suggested that early identification of superior families at age 9 is feasible at age 5 or 6 in Pinus koraiensis S. et Z.

• Journal of Soil and Groundwater Environment
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• v.12 no.5
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• pp.39-53
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• 2007

Generally, fractured medium can be described with some key parameters, such as hydraulic conductivities or random field of hydraulic conductivities (continuum model), spatial and statistical distribution of permeable fractures (discrete fracture network model). Investigating the practical applicability of the well-known conceptual models for the description of groundwater flow in fractured media, various types of hydraulic tests were applied to studies on the highly fractured media in Geumsan, Korea. Results from single-hole packer test show that the horizontal hydraulic conductivities in the permeable media are between $7.67{\times}10^{-10}{\sim}3.16{\times}10^{-6}$ m/sec, with $7.70{\times}10^{-7}$ m/sec arithmetic mean and $2.16{\times}10^{-7}$ m/sec geometric mean. Total number of test interval is 110 at 8 holes. The number of completely impermeable interval is 9, and the low permeable interval - below $1.0{\times}10^{-8}$ m/sec is 14. In other words, most of test intervals are permeable. The vertical distribution of hydraulic conductivities shows apparently the good correlation with the results of flowmeter test. But the results from the cross-hole test show some different features. The results from the cross-hole test are highly related to the connectivity and/or the binary properties of fractured media; permeable and impermeable. From the viewpoint of the connection, the application of the general stochastic approach with a single continuum model may not be appropriate even in the moderately or highly permeable fractured medium. Then, further studies on the investigation method and the analysis procedures should be required for the reasonable and practical design of the conceptual model, with which the binary properties, including permeable/impermeable features, can be described.

• Journal of Soil and Groundwater Environment
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• v.12 no.5
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• pp.19-32
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• 2007

In Korea, there have been various methods of estimating groundwater recharge which generally can be subdivided into three types: baseflow separation method by means of groundwater recession curve, water budget analysis based on lumped conceptual model in watershed, and water table fluctuation method (WTF) by using the data from groundwater monitoring wells. However, groundwater recharge rate shows the spatial-temporal variability due to climatic condition, land use and hydrogeological heterogeneity, so these methods have various limits to deal with these characteristics. To overcome these limitations, we present a new method of estimating recharge based on water balance components from the SWAT-MODFLOW which is an integrated surface-ground water model. Groundwater levels in the interest area close to the stream have dynamics similar to stream flow, whereas levels further upslope respond to precipitation with a delay. As these behaviours are related to the physical process of recharge, it is needed to account for the time delay in aquifer recharge once the water exits the soil profile to represent these features. In SWAT, a single linear reservoir storage module with an exponential decay weighting function is used to compute the recharge from soil to aquifer on a given day. However, this module has some limitations expressing recharge variation when the delay time is too long and transient recharge trend does not match to the groundwater table time series, the multi-reservoir storage routing module which represents more realistic time delay through vadose zone is newly suggested in this study. In this module, the parameter related to the delay time should be optimized by checking the correlation between simulated recharge and observed groundwater levels. The final step of this procedure is to compare simulated groundwater table with observed one as well as to compare simulated watershed runoff with observed one. This method is applied to Mihocheon watershed in Korea for the purpose of testing the procedure of proper estimation of spatio-temporal groundwater recharge distribution. As the newly suggested method of estimating recharge has the advantages of effectiveness of watershed model as well as the accuracy of WTF method, the estimated daily recharge rate would be an advanced quantity reflecting the heterogeneity of hydrogeology, climatic condition, land use as well as physical behaviour of water in soil layers and aquifers.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.6 no.3
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• pp.532-543
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• 1999

This study was conducted to provide the basic data necessary for the improvement of the teaching method for basic nursing practice as well as the effectiveness of the practice by examining the students' competency in cleansing enema after doing the self study instead of the traditional education. To examine the competency in cleansing enema after the self study, this study is an one group pretest-posttest design that subjects did the enema practice through the self study. The subjects were 89 sophomore students at Y University. College of Nursing. In basic nursing lab practice class, cleansing enema self study module was given to the students which was developed by the researcher based on the literature review and asked them to finish doing the pre study and checking the self study evaluation criteria after reading the goal, learning activities and theoretical guideline. After watching the video tape, students practiced the process in the module by themselves. For the competency in cleansing enema. repeated autonomous practices were done during the open lab other than the regular class. Whenever the practice was done, the frequency and time were measure and documented. When the student felt confident through repeated practices, the competency was evaluated by the researcher and two assistants based on the evaluation criteria. And the process was repeated till the student could perform all the items on evaluation criteria completely. The data were collected for 42 days from Oct. 15 to Nov. 26 in 1996. Collected data were analyzed by frequency, percentage, Pearson correlation coefficient and variance analysis. The results are summarized as follows : 1. 43.2% of the students were favorable to nursing and 63.6% like lecture, but 71.6% like practice. So they were more interested in practice than in lecture. 2. 62.3% of the students scored high in written test, 97.8% scored high in practice. So the practice score was better. 3. The frequency of repeated practice to pass the test ranged from 1 to 4 and the average is 2.2. 4. The average time needed in preparation and the performance was nearly the same regardless of the frequency. It took 5 to 38 minutes for those who passed the test after practicing once and the average was 16 minutes. 5 to 60 minutes were taken for those who practiced twice to pass the test and the average was 21 minutes. Those who passed the test after three practices needed 8 to 30 minutes and the average was 15 minutes, which was similar to the time that the students who passed the test for the first trial. Only one student passed the test after 4 practices and it took 10 minutes. 5. 64% of the students agreed that the context and the content of the module were appropriate for the self study and 68.2% were satisfied. And 71.9% said that the module helped them to practice the enema self study 6. Though only 42% of the students were satisfied with the video. 50.6% said that it was helpful for the self study. 7. 52.3% of the students were satisfied with the self study method, and 86.6% obtained self-confidence when performing the enema. 8. The lower the student's practice score was, the more practices were needed for them to pass the test(r=-.213, P<.05). As a result, for performing the enema practice competently, two or more practice opportunities were needed to be given. And it is possible to obtain the less complex nursing skills through the self study, when enough learning resources and assistance such as learning guidance or video tapes are provided. Based on this study. I want to suggest that. 1. There must be college policy that can support the new method instead of the traditional learning method for the students to attain the proficiency in basic nursing skills. 2. The assistant materials should be developed as soon as possible to promote the self study of basic nursing skills.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.10 no.1
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• pp.11-19
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• 2007

Purpose: Henoch-Sch$\"{o}$nlein purpura (HSP) is a systemic vasculitis involving the skin, joints, gastrointestinal tract, and kidney. Although the pathogenesis of HSP is still unclear, tumor necrosis factor (TNF-${\alpha}$) is regarded as an important cytokine contributing to the disease. The goal of this study was to determine the role of TNF-${\alpha}$ in the pathogenesis of HSP, and to evaluate the TNF-${\alpha}$ polymorphism for genetic susceptibility to HSP. Methods: From March 2004 to November 2005, 40 children with HSP and 32 healthy controls were included. Serum TNF-${\alpha}$ levels were measured using the ELISA method during the acute and convalescent phase of HSP. The genotypic and allelic frequencies of the TNF-${\alpha}$ gene polymorphisms at positions -308 and -238 were evaluated in patients and controls. Results: Serum TNF-${\alpha}$ levels were $23.17{\pm}11.31$ pg/mL in the acute phase of children with HSP and $10.56{\pm}5.59$ pg/mL in the convalescent phase (p=0.000). There was no significant correlation between the serum TNF-${\alpha}$ levels and the clinical scores of HSP (r=0.310, p=0.070). The genotypic frequency of the TNF-${\alpha}$ -308 polymorphism in children with HSP was not significantly different compared to healthy controls (GG 80%, GA 20% vs. GG 93.8%, GA 6.2%; p=0.094). The genotypic frequency of the TNF-${\alpha}$ -238 polymorphism in children with HSP was not significantly different (GG 97.5%, GA 2.5% vs. GG 93.8%, GA 6.3%; p=0.429). Conclusion: TNF-${\alpha}$ is assumed to be the main cytokine associated with the pathogenesis of HSP during the acute phase. However, the presence of TNF-${\alpha}$ gene polymorphisms at positions -308 and -238 did not distinguish children with HSP from normal controls.

• Journal of the Korean Institute of Landscape Architecture
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• v.43 no.4
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• pp.87-97
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• 2015

There's a trend towards vitalization of nightscape planning businesses nationally and locally as well for city image making and activation of regional economy, but there is still no systematic nightscape planning going on for lack of relevant researches and objective evaluations. This study aims to suggest the guideline for nightscape planning by conducting an eye tracking experiment and survey for recognizing the characteristics of a nightscape. Furthermore, the authors intended to verify the eye-tracking method as a tool for landscape evaluation. The research site was restricted in the campus of Virginia Tech, VA, and those were selected by experts' survey among various types of nightscape images. The variables for analyzing the characteristics of nightscape images selected were 'preference', 'safety(fear)' and 'clearness'. 'Fixation duration', 'saccade duration', 'scan path length', and 'pupil size' were selected as the eye movement measurements. The results of this study are as follows: The first outcome found was that there were significant differences among the characteristics(preference, safety and clearness) of a nightscape by MANOVA, and these variables were correlated positively by Pearson's correlation. Secondly, there were differences on fixation duration, saccade duration and scan path depending on the nightscape setting statistically. Also, the eye tracking measurement in an open setting was recorded lower than enclosed settings. In the result of a heat map, we found the meaning of the fixated areas on both viewing without intention and viewing intentionally. It turned out that the fixated areas were consistent with the areas the subjects felt preferred and clarity in all of the nightscape images, which means people usually focus on what they prefer and see clearly in a certain nightscape. Based on this result and previous studies, the authors could make a conclusion that eye tracking method can apply to evaluate nightscape settings in terms of analyzing the whole characteristics and finding specific points for the detailed analysis as well. Therefore, these results can contribute by suggesting nightscape planning, implication of the landscape evaluation, and implication of the eye tracking study.

• Journal of Korean Home Economics Education Association
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• v.20 no.3
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• pp.1-16
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• 2008

The purpose of this study is to investigate the perception of middle schooler's lesson of 9th grade "Housing Education" Questionnaire survey was conducted with 394 middle school students in Gyeongnam in 2006 and the dada analyzed by the descriptive statistics, t-test, One-way ANOVA, Duncan's multiple range test, Pearson correlation and multiple regression analysis by using SPSS 14. program. The result of this study were as follows. The unit 'Use of dwelling space' was perceived useful in real life, interesting in explanation & visual materials of the text, taught easily to understand the students and ranked highest in class satisfaction compared with the rest two units. The unit 'Indoor environment & equipment' was least interesting, most difficult and ranked lowest in class satisfaction. The unit 'House management & repair' was relatively interesting and easy, but not useful in real life, not much interesting in explanation & visual materials in text, taught difficult by teachers. The class satisfaction ranked second of the units. Female students perceived that the unit 'Use of dwelling space' was easy, but male students perceived that all the units were interesting in the explanation & visual materials in textbook, various teaching-learning methods, interesting experiment & practice, and was satisfied with the unit 'House management & repair'. As their academic achievement of "Technology & Home Economics" was lower, they perceived that the education contents and various experiment & practice were more difficult. The class satisfaction of middle schoolers about the unit "Housing Education" were affected by how easily the teacher taught the subject, making it more understandable, the level of difficulty of the contents and the level of interest of explanation & visual materials of text.