• Journal of Korean Elementary Science Education
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• v.21 no.1
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• pp.1-11
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• 2002

The purpose of the study is to compare and analyze the elementary science textbooks' contents between the United States(Science Horizons) and Korea for teaching the Returnee students. The analyzed contents are the name of chapters, the number of chapters, the page amounts of chapters, the structure of chapters and the studying time of chapters. The results of this study are : 1. Korean science textbook's number is 20. 'Science Horizons' has 6. Korean science textbook's total number of chapter is 58, 'Science Horizons' is 75. Korean science textbook's total number of page is 1,60.3, 'Science Horizons' is 2,106. So 'Science Horizons' has more number of chapter and page than Korean textbooks. 2. The ratio of Korean science textbook's contents is as follows: physical area, 22.4%; chemistry area, 12 1％: biology area, 39.6%; earth science area, 25.9%. But the ratio of 'Science Horizons' science textbook's contents is as follows: physical area,21.3%; chemistry area,4.0%; biology area, 46.7%; earth science area. 28.0%. 3. In case of 'Predicting the Weather' chapter, Korean science textbook has 3 lessons, 17 themes and 11 activities, whereas' Science Horizons' has 5 lessons, 10 themes and 5 activities. 4. The themes or chapters of 'Science Horizons' to propose deeper than Korea are about animals and plants, energy and movement, weather and season. our body, and earth and outer space. In case of Korean textbook are about chemistry area, the rock and volcanic activity and electric circuit. There are some differences between Korean and the United States' elementary science curriculum and textbook's contents. And the returnee students has many troubles to adapt korean science curriculum, textbooks and educational environment,;. Therefore, teachers should know and understand that, and help them.

• The Korean Journal of Financial Management
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• v.21 no.2
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• pp.65-98
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• 2004

This paper analyzes the foreign exchange exposure and the influence of determinants on the significant exposure under various return horizons of US dollar and the Japanese yen. Also this research is extended to the existence of asymmetric exposures to foreign exchange risk. The exchange rate exposures exhibit significant time variations that are very large to represent changes in cash flow sensitivities, but the relation of the significant exposures and time variations is not monotonically increasing. The extent to which a firm is exposed to exchange rate fluctuations can be explained by the level of the growth potential, nm size and leverage. For the various return horizons, firms with a higher growth potential tend to have higher exposures. And the larger firms' exposures tend to be smaller. The influences of the level of export ratio and leverage vary with return horizons and each periods. It is found that the exposures of fins are asymmetric. The asymmetry is mainly explained by the market share hypothesis. The level of export ratio commonly influences the asymmetric exposures to the US dollar and the Japanese yen.

• Journal of Families and Better Life
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• v.26 no.5
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• pp.109-127
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• 2008

There are few studies on the characteristics of debtors in individual rehabilitation procedures, though research in this field is needed. The scarcity of research means that public policy and perception are being made with inadequate information and, to a certain extent, based on personal prejudices and misconceptions. The purpose of this study was to find out demographic, economic and psychological characteristics of debtors in individual rehabilitation procedures. For this study, an in-depth interview was used. The major findings were as follows : The focus of this study is debtors in individual rehabilitation procedures. They were all under 40 and received relatively high educations. Interestingly, they showed a high tendency to use debt and an inability to manage their money. They had short time horizons and imperfect self-control in consumption and borrowing decisions. Monthly income, expenditures, asset and debt of the debtors, and monthly payment to creditors were reported. There were a lot of reasons for their bankruptcy : business failure, job loss, the cost of raising children, and expenditures for entertainment causing them to file for individual rehabilitation procedures. One of the major conclusions of this study was the discovery that their psychological characteristics were nearly the same. The implications of the study suggest that financial education and counseling must consider psychological characteristics.

• Geophysics and Geophysical Exploration
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• v.4 no.3
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• pp.80-83
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• 2001

Four seismic reflection horizons in 3-D seismic data, coherence derived from the seismic data, and 38 well logs from the Boonsville Gas Filed in Texas were tried to be integrated and visualized in 3 dimensions. Time surface was constructed from pick times of the reflection horizons. Average velocities to each horizon at 38 well locations were calculated based on depth markers from the well logs and time picks from the 3-D seismic data. The time surface was transformed to depth surface through velocity interpolation. Coherence was calculated on the 3-D seismic data by semblance method. Spatial distribution of the coherence is captured easily in 3-D visualization. Comparing to a time-slice of seismic data, distinctive stratigraphic features could be correctly recognized on the 3-D visualization.

• Korean Journal of Soil Science and Fertilizer
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• v.48 no.3
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• pp.194-204
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• 2015

Six study sites in Gumi, Goryeong in Gyeongbuk province and Naju in Jeonnam province were selected to investigate soil properties of poorly drained horizons in paddy soils. The horizons were re-established layers which were parent material layers originated from fluvial deposits. Topsoil layers were differentiated from piled parent materials while soil structure of the topsoil layer was massive with striated microstructure. Compaction at soil re-establishment and a lack of structure and aggregate development in these soils may cause the limitation of vertical water movement and result in poorly drained horizons. Soil samples were taken from paddy fields with top soils of sandy loam, silt loam and silty clay loam and re-established soils of coarse and fine texture. The samples were taken from each horizon for the analyses of soil chemical and mineral properties. Soils with re-established soils of coarse texture had greater amounts of sands from top soil texture distributions, while soils with fine texture had greater amounts of silts. Chemical properties of top soils were analyzed from rice cultivated soils at the time of re-establishments and one year after the re-establishments. The coarse texture of the re-established horizons decreased in EC values from 0.23 to $0.11(dS\;m^{-1})$, available phosphate values from 112 to $54(mg\;kg^{-1})$, and exchangeable Ca values from 6.6 to $4.9(cmol_c\;kg^{-1})$. On the other hand, soils with fine texture showed decrease only in pH and exchangeable Ca values. Especially, organic matter and available phosphate contents showed heterogeneous distributions from each horizon. This result may be caused by mixture of plough layer and subsurface layer during and consolidation. Hydraulic conductivity values were low at the boundaries of top soil and parent material layers except SL/coarse soil. Soil microstructure was massive structure without soil clods or pores and showed striated structure. Therefore, re-established paddy fields with fluvial deposits as parent material layers showed limited vertical movements of soil water because of occurrence of compacted layers and less-development of soil clods and aggregates.

• International Journal of Advanced Culture Technology
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• v.11 no.4
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• pp.393-405
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• 2023

Accurate prediction of wind speed and power is vital for enhancing the efficiency of wind energy systems. Numerous solutions have been implemented to date, demonstrating their potential to improve forecasting. Among these, deep learning is perceived as a revolutionary approach in the field. However, despite their effectiveness, the noise present in the collected data remains a significant challenge. This noise has the potential to diminish the performance of these algorithms, leading to inaccurate predictions. In response to this, this study explores a novel feature engineering approach. This approach involves altering the data input shape in both Convolutional Neural Network-Long Short-Term Memory (CNN-LSTM) and Autoregressive models for various forecasting horizons. The results reveal substantial enhancements in model resilience against noise resulting from step increases in data. The approach could achieve an impressive 83% accuracy in predicting unseen data up to the 24th steps. Furthermore, this method consistently provides high accuracy for short, mid, and long-term forecasts, outperforming the performance of individual models. These findings pave the way for further research on noise reduction strategies at different forecasting horizons through shape-wise feature engineering.

• Journal of the Korean Operations Research and Management Science Society
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• v.27 no.2
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• pp.1-13
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• 2002

In this paper, we compares the business failure prediction accuracy among Linear Programming Discriminant Analysis(LPDA) model, Multivariate Discriminant Analysis (MDA) model and logit analysis model. The Data for 417 companies analyzed were gathered from KIS-FAS Published by Korea Information Service in 1999. The result of comparison for four time horizons shows that LPDA Is advantageous in prediction accuracy over the other two models when over all tilt ratio and business failure accuracy are considered simultaneously.

• Bulletin of the Korean Mathematical Society
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• v.50 no.2
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• pp.611-626
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• 2013

In the paper we study the finite-time ruin probability in a general risk model with constant interest force, in which the claim sizes are pairwise quasi-asymptotically independent and arrive according to an arbitrary counting process, and the premium process is a general stochastic process. For the case that the claim-size distribution belongs to the consistent variation class, we obtain an asymptotic formula for the finite-time ruin probability, which holds uniformly for all time horizons varying in a relevant infinite interval. The obtained result also includes an asymptotic formula for the infinite-time ruin probability.

• KDI Journal of Economic Policy
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• v.37 no.4
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• pp.1-20
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• 2015

We examine the validity of popular exchange rate models such as the purchasing power parity (PPP) hypothesis and the monetary model for Korean won/US dollar exchange rate. Various specification tests demonstrate that Korean data are more favorable for both models based on time-varying cointegration coefficients as compared to those based on constant cointegration coefficients. When the abilities to predict future exchange rates between those models based on time-varying cointegration coefficients are compared, an in-sample analysis shows that the time-varying PPP (monetary model) has better predictive power over horizons shorter (longer) than one year. Results from an out-of-sample analysis indicate that the time-varying PPP outperforms models based on constant cointegration coefficients when predicting future exchange rate changes in the long run.

• Communications for Statistical Applications and Methods
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• v.18 no.1
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• pp.13-21
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• 2011

This paper studies the analysis of multivariate nonstationary time series with seasonality. Three types of multivariate time series models are considered: seasonal cointegration model, nonseasonal cointegration model with seasonal dummies, and vector autoregressive model in seasonal differences that are compared for forecasting performances using Korean macro-economic time series data. The cointegration models produce smaller forecast errors in short horizons; however, when longer forecasting periods are considered the vector autoregressive model appears preferable.