• Annals of Clinical Neurophysiology
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• v.1 no.1
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• pp.26-30
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• 1999

Background : The origin of P300 was still on debate nbut thought to be in the frontal, temporal or parietal lobe. As the transcranial doppler ultrasonography(TCD) gives us and opportunity to observe hemodynamic chaged dynamically and the middle cerebral artery feeds these ares of the hemisphere, we observed the change of mean flow velocity of MCA during the event related potential test(ERP) to determine the role of these structures in P300 generation. Method : Twenty normal subjects(male : 13, age : 24-29 years) performed ERP. An auditory oddball pardigm was used to elicit the ERPs. TCD examination was performed with 2-MHz probe monitoring the left MCA(Transscan, EME). After signal identification and adjustments to maximize the Doppler signal strength, the probe was mechanically locked during the monitoring. The changes of blood flow velocity of the left middle cerebral artery(MCA) induced by cognitive demands were monitored. The measurement of the meal flow velocities(MFV) of MCA were made while the subjects were prior to, during, and after ERP. We recorded the MFVs during ERP. Statistical analysis was performed using t-tests with SPSS-PC for windows release 6.0. Results : All subjects showed a relative increase in MFV of MCA during the task. The mean rise was about 3.2-4.2%(p <0.05). Although TCD does not measure absolute values of regional cerebral blood flow(rCBF) or absolute rCBF changes, changes of flow velocity can reflect relative rCBF changes. Conclusions : The generation site of P300 still remains unclear but the neocortical, thalamic and limbic region and temporal-parietal cortex have been proposed. The MCA supplies these anatomical structures. The Changes of flow veolocity of MCA during the ERP test suggest that the some part of the brain fed y the MCA activate of the temporal lobe or parietal lobes, we can deduce that some parts of brain fed by the MCA participate in the generation of P300.

• The Journal of Engineering Geology
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• v.23 no.4
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• pp.353-361
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• 2013

To analyze the distribution of earthquake-induced strain data in rock masses, statistical analysis was performed on four-directional strain data obtained from a ground movement monitoring system installed in Korea. Strain data related to the 2011 Tohoku-oki earthquake and two aftershocks of >M7.0 in 2011 were used in x-MR control chart analysis, a type of univariate statistical analysis that can detect an abnormal distribution. The analysis revealed different dispersion times for each measurement orientation. In a more comprehensive analysis, the strain data were re-evaluated using multivariate statistical analysis (MSA) considering correlations among the various data from the different measurement orientations. $T_2$ and Q-statistics, based on principal component analysis, were used to analyze the time-series strain data in real-time. The procedures were performed with 99.9%, 99.0%, and 95.0% control limits. It is possible to use the MSA data to successfully detect an abnormal distribution caused by earthquakes because the dispersion time using the 99.9% control limit is concurrent with or earlier than that from the x-MR analysis. In addition, the dispersion using the 99.0% and 95.0% control limits detected an abnormal distribution in advance. This finding indicates the potential use of MSA for recognizing abnormal distributions of strain data.

• Journal of Korea Water Resources Association
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• v.40 no.9
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• pp.677-685
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• 2007

The objective of this study is to evaluate the applicability of multi-objective genetic algorithm(MOGA) in order to calibrate the parameters of conceptual rainfall-runoff model, Tank model. NSGA-II, one of the most imitating MOGA implementations, is combined with Tank model and four multi-objective functions such as to minimize volume error, root mean square error (RMSE), high flow RMSE, and low flow RMSE are used. When NSGA-II is employed with more than three multi-objective functions, a number of Pareto-optimal solutions usually becomes too large. Therefore, selecting several preferred Pareto-optimal solutions is essential for stakeholder, and preference-ordering approach is used in this study for the sake of getting the best preferred Pareto-optimal solutions. Sensitivity analysis is performed to examine the effect of initial genetic parameters, which are generation number and Population size, to the performance of NSGA-II for searching the proper paramters for Tank model, and the result suggests that the generation number is 900 and the population size is 1000 for this study.

• Korean Journal of Psychosomatic Medicine
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• v.11 no.1
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• pp.60-68
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• 2003

Objectives: The purpose of this study was to develop a Korean version of the Levels of Emotional Awareness Scale(LEAS-K) and to examine its validity and reliability. Methods: LEAS-K was developed from translating original LEAS into Korean. The subjects were 476 Korean medical students(322 males and 154 females). The internal consistency was evaluated with the Cronbach's alpha coefficients and 40 protocols were independently scored by two raters to confirm interrater reliability. Additionally, a Korean version of 20-item Toronto Alexithymia Scale(TAS-20K), Korean versions of the Openness to Experience Inventory(OE), the Marlowe-Crowne Scale (MCS), the Bendig short form of the Taylor Manifest Anxiety Scale(TMAS) and the Emotional Expressivity Scale(EES) were rated to evaluate concurrent validity. Results: The internal consistency measured by Cronbach's alpha was 0.81 and interrater reliability was high{r(40)=0.99}. Correlation coefficients for concurrent validity were nonsignificant with TMAS and EES. LEAS-K correlated significantly with TAS-20K{r(476)=-0.10, p<0.05}, OE {r(476)=0.10, p<0.05} and MCS {r(476)=0.10, p<0.05}. Conclusion: LEAS-K was demonstrated to have high reliability and validity.

• International Commerce and Information Review
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• v.13 no.3
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• pp.203-228
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• 2011

In one global industry after another, supply chains are reaching across continents farther and deeper than they have ever been. As a result, global companies are confronting new and more formidable supply chain risks which insurance policies alone cannot overcome. This is especially true in the Korean manufacturing industry, where the integration of Supply Chain Management and Risk Management has become critical among Korean export manufactures. One of the most effective ways to manage supply chain risks is to prevent them from occurrence. First, however, supply chain managers must have the knowledge to identify potential causes of supply chain risks. This paper attempts to contribute to such knowledge by examining the relationships between Risk Management, Business Partnership, and Business Performance among Korean export manufacturers. Our study analysed 105 cases in Korean supply chain management and then developed a structural equation model. From our model we found that Supply Chain Risk Management affects both Business Performance and Business Partnerships among Korean export manufacturers. Our model also revealed that the practice of Risk Management within the Supply Chain of Korean export manufacturing industry is impeded by certain constraints and limitations.

• Food Science and Preservation
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• v.15 no.6
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• pp.810-815
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• 2008

Improving quality is a very important component of maintaining competitiveness of agricultural products. However, evaluation of 'high quality' indicates it is a very abstract concept and independent of some quality attributes, leading to differences in the perception of quality. Thus, there is a pressing need to objectively define 'high quality' and to develop basic technologies for its measurement, for application in the production, storage and distribution of competitive agricultural products. To objectively quantify apple quality, a survey was conducted on consumer preferences and awareness of quality attributes including color, taste, flavor and shape. The survey questionnaire targeted male and female adults (463 persons) ranging in age from 20 to 59 years. The questionnaire was based on purchases made at a wholesale market (50.1%) or a traditional market (18.8%). The majority of purchases were as small packets (62.0%) or as individual pieces (20.5%). Apples of moderate size (fist size, 60.5%) were preferred over small (4.3%) or large (32.6%) apples. The questionnaire provided consumer data on external quality attributes including color, shape and variety. Taste attributes were evaluated in relation to the balance between sour and sweet taste, and flavors peculiar to apples.

• Science of Emotion and Sensibility
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• v.12 no.4
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• pp.489-500
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• 2009

This research takes a user-centered approach to define relevance, the core concept in information retrieval. The literature on relevance has identified numerous factors affecting such a judgment. We examined the model of user relevance judgment that describes the relationship between user relevance criteria and different types of relevance with information search task. We consider 7 criteria of user relevance-topicality, novelty, reliability, understandability, specificity, richness, and interest-and 3 type of user relevance-cognitive relevance, situational relevance, and affective relevance. Data were collected from a semi-controlled survey and analyzed by a structural equation modeling. As a result, topicality and reliability were found to be the essential relevance criteria in all information retrieval tasks. In the fact search task, topicality, reliability, novelty, richness, and interest were found to be significant. In the problem solving search task, topicality, reliability, understandability, and specificity were found to be significant. In the decision making search task, topicality, reliability, novelty, understandability, richness, specificity, and interest were found to be significant. In addition, the relationships between types of user relevance were determined. This research made theoretical and practical contributions to the field of information retrieval by identifying a definite model of user relevance judgment.

• Journal of the Korean Society for information Management
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• v.30 no.4
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• pp.215-239
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• 2013

Even though the overall scholarly community has recognized a dramatic growth and changes in the Information Science research in Korea over the last few decades, there are still only few studies that have identified the changes in terms of long-term and dynamic point of view. We have analyzed 1,007 IS-research articles from leading Korean journals in KCI (Korea Citation Index), published between 2000 and 2011. To discern the trendline of changes in research interests over time, we conducted a time-series analysis by developing grounded subject scheme from the article set and checking the growth rate of the number of published articles and title keywords. A comparative analysis was also conducted by constructing and comparing co-word maps over time to discover visible changes in research topics over this 12-year period of the IS-research in Korea. As a result, we identified some developments and transformations in major subject areas and knowledge structure of the IS-research in Korea over time. The major trend we discovered is that IS-studies over the 12-year period evolved from system-oriented research to library-application research. The changes are especially observed in knowledge management, Web-based system evaluation, and information retrieval areas. When compared to the results of other studies, the result of our study may serve as an evidence of the localization of Korean IS-studies in the first decade of the $21^{st}$ century.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.5
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• pp.543-548
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• 2017

This paper examines the effects of strong corporate governance for listed companies in accessing capital markets from the point of view of the weighted average cost of capital. Results found that corporate governance had a significant negative(-) relation to the weighted average cost of capital. This finding is consistent with previous research and implies that the higher shareholder ownership and foreign ownership have confidence in the financial information of the company, and therefore, risk is reduced for investors. This results in lower expected rates of return and companies will pay a lower cost of capital. Second, tax evasion had a positive effect(+) on the weighted average cost of capital. The low quality of corporate accounting information is expected to increase tax avoidance. Accordingly, this results in increased risk. If the required rate of return is high in its impact,it leads to increased capital costs. In addition, corporate governance and tax avoidance factors showed a negative affect (-) on the weighted average cost of capital. Corporate governance plays an important role in tax avoidance and the weighted average cost of capital, and strong corporate governance reducesthe impact on tax avoidance. In addition, the weighted average cost of capital in capital markets showed the reducing effect.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.38 no.2
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• pp.103-118
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• 2012

In this study, the cellular protective effect of isoquercitrin against $H_2O_2$ and rose bengal-indued HaCaT cell damage was investigated. The ethosome and elastic liposome for enhanced transdermal delivery were prepared. Particle size, loading efficiency and cumulative permeated amounts of them were evaluated. Isoquercitrin didn't show any characteristic cytotoxicity at 50 ${\mu}M$. When HaCaT cells were treated with 5 mM $H_2O_2$ and 25 ${\mu}M$ rose bengal, isoquercitrin protected the cells against the oxidative damage in a concentration dependent manner (6.25 ~ 50 ${\mu}M$). The size of 0.03 % isoquercitrin loaded ethosome was 222.85 nm and the loading efficiency was 82.26 %. The ethosome loaded with 0.03 % isoquercitrin was stable and maintained the constant particle size for 2 weeks after being prepared. The ethosome exhibited more enhanced skin permeability than general liposome and ethanol solution. The optimal ratio of lipid to surfactant of 0.1 % isoquercitrin loaded elastic liposomes was observed to be 89 : 5 through evaluating particle size (341.2 nm), deformability index (59.89), loading efficiency (54.3 %), and skin permeability (54.4 %).