• Journal of Environmental Impact Assessment
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• v.19 no.1
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• pp.15-28
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• 2010

Because deterioration of air quality and urban heat island directly harm health of citizens, Health Impact Assessment (HIA) and Environmental Impact Assessment (EIA) for urban development projects needs to conduct analysis of their impacts objectively. This study aims to review appropriate methods for assessment of air quality used at each stage of urban development and to investigate prediction and assessment methods of urban heat island. In addition, by evaluating impacts of climate change following supposed urban construction performed in the central area of Korea on public health, it examines usefulness of HIA for urban construction. When urban heat island prediction and HIA method suggested in this study are applied to an imaginary city, they predict urban heat island properly and the impacts of climate changes on public health inside the city could be determined clearly by calculating life-climate index and bio-climate index related with thermal environment from the model.

• Korean Journal of Environmental Biology
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• v.17 no.4
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• pp.493-498
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• 1999

To verify the usefulness of enzyme activities as a index for the stability or maturity of organic refuse composting such as grape pomace, Vmax of $\beta$-glucosidase, cellobiohydrolase and alkaline phosphatase were measured. The peak values of all measured enzymes at the initial stage of composting were probably associated with easily degradable organic matter in the grape pomace and decreased gradually. But the activities of $\beta$-glucosidase and cellobiohydrolase were increased again rapidly whereas that of alkaline phosphatase remained approximately constant after 60 composting days. These results suggest that the increase of enzyme activities during the later periods of grape pomace composting process could be used as a index for their stability.

• Journal of Korean Library and Information Science Society
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• v.45 no.3
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• pp.415-440
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• 2014

This study intends to make a comprehensive inquiry into the meaning and limitations of Discovery, and to explore how to make full use of Discovery in library cataloging. To this end, first discussed is the meaning of Discovery, which has a variety definitions. For the quality evaluation, 5 criteria were developed on the basis of literature review. Then this study conducted the quality evaluation on the basis of previously developed 5 criteria and usefulness of Discovery in library catalogs is thoroughly discussed. Based on these, the final discussion includes strategies for Korean LIS scholars and library practitioners to consider when applying Discovery as an integrated search tool.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2016.05a
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• pp.284-285
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• 2016

In this paper, reflecting the index of concentration and real-time EEG measurement, implementation of the game-type content that can be centralized power of training. Implemented content, for more effective training, based on the brain wave difference in each user, by reflecting an indication of concentration, it is possible by level training. In order to evaluate the usefulness of the implemented content, to target the five subjects, is underway to improve training of concentration, through a comparative analysis of the changes in the index of ability to concentrate, to confirm the improvement of the concentration of the user it could be.

• Journal of Trauma and Injury
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• v.32 no.1
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• pp.17-25
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• 2019

Purpose: We investigated how prehospital, emergency room (ER), and delta shock indices (SI) correlate with outcomes including mortality in patients with polytrauma. Methods: We retrospectively reviewed the medical records of 1,275 patients who visited the emergency department from January 2015 to April 2018. A total of 628 patients were enrolled in the study. Patients were divided into survivor and non-survivor groups, and logistic regression analysis was used to investigate independent risk factors for death. Pearson coefficient analysis and chi-square test were used to examine the significant relationship between SI and clinical progression markers. Results: Of 628 enrolled patients, 608 survived and 27 died. Multivariate logistic regression analysis reveals "age" (p<0.001; OR, 1.068), "pre-hospital SI >0.9" (p<0.001; OR, 11.629), and "delta SI ${\geq}0.3$" (p<0.001; OR, 12.869) as independent risk factors for mortality. Prehospital and ER SIs showed a significant correlation with hospital and intensive care unit length of stay and transfusion amount. Higher prehospital and ER SIs (>0.9) were associated with poor clinical progression. Conclusions: SI and delta SI are significant predictors of mortality in patients with polytrauma. Moreover, both prehospital and ER SIs can be used as predictive markers of clinical progression in these patients.

• Spatial Information Research
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• v.17 no.1
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• pp.117-129
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• 2009

South Korea has been undergoing spring drought periodically and diverse researches using vegetation index have been carried out to monitor spring droughts. The strength of the vegetation index-based drought monitoring is that the monitoring method enables efficient spatio-temporal grasp of changes in drought events. According to the development of low resolution satellite images such as MODIS, which are characterized by outstanding temporal resolution, the use of the method is expected to increase. Drought analysis using vegetation index considered only meteorological factor as a cause that affects vitality of vegetation. But many indirect and direct factors affect vegetation stress, So many uncertainties are involved in such method of analysis. To secure objectivity of drought analysis that uses vegetation index it is therefore necessary to compare the method with most representative drought analysis tools that are used for drought management. In this study, PDSI and SPI which a meteorological drought index that quantifies drought and that is used as a basic index for drought monitoring and MODIS NDVI are compared to propose correlation among them and to show usefulness of drought assessment that uses vegetation index. This study shows changing patterns of NDVI and SPI 6-month are similar and correlation between NDVI and SPI was highest in inland vegetation cover.

• Journal of the Korea Convergence Society
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• v.9 no.11
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• pp.307-313
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• 2018

In this study, analyzed the effect of the introduction and operation of internal control system of a company on accounting information usefulness in a rapidly changing business environment. In order to conduct this study, we studied a comprehensive analysis on the usefulness of internal control and accounting information, and applied the research model to the purpose of this study. In this study, we analyzed the degree of the relationship between variables based on the discretionary accruals of the modified Jones model using the internal control evaluation index based on the components of the internal control system for China. In the empirical analysis, analyzed that the operation of internal control has a negative influence on discretionary accruals, which is a substitute for usability of accounting information. In addition, the risk management factors of the internal control system have a negative correlation with the usefulness of accounting information. The results of this study suggest that it is possible to present the positive function of internal control system to many firms where the introduction and operation of internal control is important, and to provide useful guidance in the study of the relationship between the operation of internal control and discretionary accruals for foreign company.

• Journal of Intelligence and Information Systems
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• v.17 no.3
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• pp.187-201
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• 2011

KOSPI200 index is the Korean stock price index consisting of actively traded 200 stocks in the Korean stock market. Its base value of 100 was set on January 3, 1990. The Korea Exchange (KRX) developed derivatives markets on the KOSPI200 index. KOSPI200 index futures market, introduced in 1996, has become one of the most actively traded indexes markets in the world. Traders can make profit by entering a long position on the KOSPI200 index futures contract if the KOSPI200 index will rise in the future. Likewise, they can make profit by entering a short position if the KOSPI200 index will decline in the future. Basically, KOSPI200 index futures trading is a short-term zero-sum game and therefore most futures traders are using technical indicators. Advanced traders make stable profits by using system trading technique, also known as algorithm trading. Algorithm trading uses computer programs for receiving real-time stock market data, analyzing stock price movements with various technical indicators and automatically entering trading orders such as timing, price or quantity of the order without any human intervention. Recent studies have shown the usefulness of artificial intelligent systems in forecasting stock prices or investment risk. KOSPI200 index data is numerical time-series data which is a sequence of data points measured at successive uniform time intervals such as minute, day, week or month. KOSPI200 index futures traders use technical analysis to find out some patterns on the time-series chart. Although there are many technical indicators, their results indicate the market states among bull, bear and flat. Most strategies based on technical analysis are divided into trend following strategy and non-trend following strategy. Both strategies decide the market states based on the patterns of the KOSPI200 index time-series data. This goes well with Markov model (MM). Everybody knows that the next price is upper or lower than the last price or similar to the last price, and knows that the next price is influenced by the last price. However, nobody knows the exact status of the next price whether it goes up or down or flat. So, hidden Markov model (HMM) is better fitted than MM. HMM is divided into discrete HMM (DHMM) and continuous HMM (CHMM). The only difference between DHMM and CHMM is in their representation of state probabilities. DHMM uses discrete probability density function and CHMM uses continuous probability density function such as Gaussian Mixture Model. KOSPI200 index values are real number and these follow a continuous probability density function, so CHMM is proper than DHMM for the KOSPI200 index. In this paper, we present an artificial intelligent trading system based on CHMM for the KOSPI200 index futures system traders. Traders have experienced on technical trading for the KOSPI200 index futures market ever since the introduction of the KOSPI200 index futures market. They have applied many strategies to make profit in trading the KOSPI200 index futures. Some strategies are based on technical indicators such as moving averages or stochastics, and others are based on candlestick patterns such as three outside up, three outside down, harami or doji star. We show a trading system of moving average cross strategy based on CHMM, and we compare it to a traditional algorithmic trading system. We set the parameter values of moving averages at common values used by market practitioners. Empirical results are presented to compare the simulation performance with the traditional algorithmic trading system using long-term daily KOSPI200 index data of more than 20 years. Our suggested trading system shows higher trading performance than naive system trading.

• Spatial Information Research
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• v.20 no.4
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• pp.47-55
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• 2012

Normalized Difference Vegetation Index (NDVI) has been used to measure and monitor plant growth, vegetation cover, and biomass from multispectral satellite data. It is also a valuable index in forest applications, providing forest resource information. In this research, an approach for monitoring forest change using MODIS NDVI time series data is explored. NDVI difference-based approaches for a specific point in time have possible accuracy problems and are lacking in monitoring long-term forest cover change. It means that a multi-time NDVI pattern change needs to be considered. In this study, an efficient methodology to consider long-term NDVI pattern is suggested using a harmonic model. The suggested method reconstructs MODIS NDVI time series data through application of the harmonic model, which corrects missing and erroneous data. Then NDVI pattern is analyzed based on estimated values of the harmonic model. The suggested method was applied to 49 NDVI time series data from Aug. 21, 2009 to Sep. 6, 2011 and its usefulness was shown through an experiment.

• Journal of The Korean Dental Society of Anesthesiology
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• v.14 no.1
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• pp.11-15
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• 2014

Background: It is imperative that adequate sedation level should be maintained for safe and effective dental sedation. Cerebral state index (CSI) is a empirically derived parameter calculated from the processed electroencephalography (EEG). We investigated whether CSI can be used as a sedation depth indicator. Methods: We continuously recorded CSI and bispectral index (BIS) values from 10 healthy children aged 3.6 yr undergoing dental sedation. We also evaluated sedation level using the Modified Observer's Assessment of Alertness/Sedation (MOAA/S). The correlation between CSI and BIS, or CSI and sedation score were sought a regression analysis. Results: There were good linearity between CSI values and sedation score. (r = 0.916, P < 0.001) The paired CSI and BIS values showed a significant correlation between the two values. (r = 0.895, P < 0.001) The difference between CSI and BIS values was not statistically significant at deep and conscious sedative levels. Conclusions: The CSI monitor can be easy to monitor sedation depth during dental sedation for children.