• Journal of applied mathematics & informatics
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• v.12 no.1_2
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• pp.199-209
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• 2003

When a sampling theorem holds in wavelet subspaces, sampling expansions can be a good approximation to projection expansions. Even when the sampling theorem does not hold, the scaling function series with the usual coefficients replaced by sampled function values may also be a good approximation to the projection. We refer to such series as hybrid sampling series. For this series, we shall investigate the local convergence and analyze Gibbs phenomenon.

• Journal of Life Science
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• v.18 no.8
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• pp.1169-1172
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• 2008

The purpose of this study was to establish blood reference values for miniature pigs from various growth ages before pre-puberty. 12 miniature pigs from two swine farms were sampled by jugular venipuncture. Routine hematological and biochemical determinations were performed using whole blood and serum. For the variables examined in each age group the means and the standard deviations were calculated. In hematological values, there are significant changes (p<0.05) in RBC, hematocrit and platelet values in each group. In RBC and hematocrit values, 4-week group shows the lowest level, whereas in platelet values, 4-week group shows the highest level. In biochemical values, there are significant chnges (p<0.05) in glucose and GGT in each group, and in other biochemical values there are no significant changes during growing periods. The values presented here may be useful for knowing the normal values for miniature pigs and also screening the normal pigs in the early days of their life and during the developemental stages.

• Korean Journal of Optics and Photonics
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• v.15 no.5
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• pp.469-474
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• 2004

We have fabricated and designed wavelength-tunable sampled grating distributed Bragg reflector laser diodes(SGDBR-LD) by using, for the first time, planar buried heterostructures(PBH). The diodes have low threshold current values and high-performance of laser operation. Growth condition using metal organic chemical vapor deposition(MOCVD) was optimized for the formation of a good butt-coupling at the interface. A maximum output power of the fabricated device was 20 mW under 200 mA continuous wave(CW) operation at $25^{\circ}C$. Average threshold current and voltage were 12 mA and 0.8 V, approximately. This output power is higher than those of ridge waveguide(RWG) and buried ridge stripe(BRS) structures by amounts of 9 mW and 13 mW, respectively. We obtained a tuning range of 44.4nm which is well matched with the target value of our design. The side mode suppression ratio of more than 35 dB was obtained for the whole tuning range. Optical output power variation was less than 5 dB, which is 4 dB smaller than that of RWG structures.

• The Korean Journal of Applied Statistics
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• v.24 no.3
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• pp.477-484
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• 2011

When an event of target variable is rare, a widespread strategy is to build a model on the sample that disproportionally over-represents the events, that is over-sampled. Using the data over-sampled from the original data set, the predicted values would be biased; however, it can be easily corrected to represent the population. In this study, we investigate into the relationship between the proportion of rare event on a data-mart and the model performance using real world data of a Korean credit card company. Also, we use the methods for adjusting of posterior probability for over-sampled data of the offset method and the weighted method. Finally, we compare the performance of the methods using real data sets.

• Journal of Ecology and Environment
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• v.42 no.4
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• pp.163-173
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• 2018

Background: Deforestation and degradation are currently affecting the ecosystem services of forests. Among the ecosystem services affected by deforestation and degradation are the amount of soil organic carbon (SOC) and total nitrogen (TN) stored in forest soils which have greater impacts in global climate change. This study aimed at examining the amount of SOC and TN in the forest fragments which were separated from the continuous tracts of forests of Jibat and Chillimo through fragmentation processes over four decades. Methods: We have sampled soils from 15 forest fragments of Chillimo and Jibat in the central highlands of Ethiopia. The soil samples obtained in two separate soil depths (0-30 and 30-60 cm) were bulked, dried, and sieved for analysis. Results: Our results have shown that the two sites (Jibat and Chillimo forest fragments) differed in their SOC and TN contents. While the values for Jibat were found to be 29.89 Mg/ha of SOC and 2.84 Mg/ha for TN, it was 14. 06 Mg/ha of SOC and 1.40 Mg/ha for TN for Chillimo. When all forest fragment soil samples were bulked together, Jibat site had twice the value of SOC and TN than Chillimo. When disaggregated on the basis of each fragments, there existed differences in SOC (1.86 Mg/ha and 42.15 Mg/ha) and TN (0.24 Mg/ha and 4.23 Mg/ha) values. Among the forest fragments, fragment four ($F_4$) had the highest Relative Soil Improvement Index (RSII) value of 3826.82% and fragment fifteen ($F_{15}$) had the lowest RSII value (726.87%) which indicated that the former had a better quality of soil properties than the latter. Conclusion: SOC and TN differed across sampled fragments and sites. Variations in soil properties are the reflections of inherent soil parent material, aboveground vegetation, human interferences, and other physical factors. Such differences could be very important for identifying intervention measures for restoration and enhancing ecosystem services of those fragments.

• Journal of Environmental Science International
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• v.7 no.4
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• pp.565-572
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• 1998

This study estimate the degree of contamination in the streamwater around the Sudokwon landfill site. It was sampled at 10 sites in Jan., Apr., Jul. and Oct., 1996. There were analyzed five kinds of toxic chemical material-CN, AES, PCB, As, Org-p, and four kinds of heavy metal-Pb, Hg, Cd, $C^{+6}$ The result are 1)The COD was generally increased to compare before landfall, 2) The Org-P and PCB were not detected at all points, 3) The concentrations of Pb, $C^{+6}$ and As were lower than the environmental criteria values, 4) The CN, Hg and Cd were over envirommental criteria values. and so emergent regulation is needed, 5) The effects of the streamwater contamination were not only the leachate of the landfall, but also the small factories and agricultural land around the landfill.

• Speech Sciences
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• v.12 no.2
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• pp.121-128
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• 2005

This study was an attempt to determine acoustic characteristics in myna bird's notes. Two myna birds' sounds imitating a normal male voice in his late 20's were sampled and analyzed. The analyses included the mean values of F1, F2, F3 and pitch contours. The results were as follows; First, there was a significan difference in the mean values of F1, F2, and F3 in isolatd vowel /a/ and /i/ between the myna birds' sounds and the human voice. However, there was no apparent difference in pitch contour of their formants. Second, there was a difference in pitch contour of their formants in their sentence ('hn-nyung-ha-se-yo?' meaning 'How are you?') production. Namely, the myna birds' pitch contour was located higher than that of the human's.

• Journal of Industrial Technology
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• v.29 no.B
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• pp.81-88
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• 2009

The main purpose of this work is to determine characteristics of undrained shear strength of remolded marine clay at Incheon. Laboratory vane tests with remolded marine clay sampled from west coast at Incheon were performed to investigate the undrained shear strength of them being dumped for reclamation after dredging from the sea bottom. Test results were compared with the predicted values of undrained shear strength proposed by many researchers. It was found that measured results about undrained shear strength with water content was in good agreements with values proposed by Mikasa and Modified Mikasa's empirical formula.

• Journal of Industrial Technology
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• v.30 no.A
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• pp.103-109
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• 2010

This research is to determine characteristics of undrained shear strength of remolded marine clay at Incheon and Busan, representing typical marine clays in Korea. Laboratory vane tests with remolded marine clays sampled from coasts at Incheon and Busan were performed to investigate the undrained shear strength of them. Test results were compared with the predicted values of undrained shear strength proposed by many researchers. It was found that measured results about undrained shear strength with water content was in good agreements with values proposed by Terzaghi empirical formula.

• Journal of IKEEE
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• v.23 no.3
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• pp.817-825
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• 2019

Difference equation is useful for control algorithm in the microprocessor. To approximate a derivative values from sampled data, it is used the methods of forward, backward and central differences. The key of computing discrete derivative values is the finite difference coefficient. The focus of this paper is a new approach method of finite difference formula. And we apply the proposed method to the recursive least squares(RLS) algorithm.