• Asia pacific journal of information systems
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• v.30 no.3
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• pp.457-496
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• 2020

This study aims to extensively analyze the performance of various Machine Learning (ML) techniques for predicting version to version change-proneness of source code Java files. 17 object-oriented metrics have been utilized in this work for predicting change-prone files using 31 ML techniques and the framework proposed has been implemented on various consecutive releases of two Java-based software projects available as plug-ins. 10-fold and inter-release validation methods have been employed to validate the models and statistical tests provide supplementary information regarding the reliability and significance of the results. The results of experiments conducted in this article indicate that the ML techniques perform differently under the different validation settings. The results also confirm the proficiency of the selected ML techniques in lieu of developing change-proneness prediction models which could aid the software engineers in the initial stages of software development for classifying change-prone Java files of a software, in turn aiding in the trend estimation of change-proneness over future versions.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 1998.10a
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• pp.521-526
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• 1998

This study was initiated to build runoff plots, install soil and water quality monitoring systems and collect background data from the plots and soils to assess runoff the nonpoint source pollution and soil physical change in mountainous soils. Eleven 3 $\times$ 15 m runoff plots and monitoring systems were installed at a field of National Alpine Agricultural Experiment Station to monitor soil physical change, and discharge of nonpoint source pollutant. Corn and potato were cultivated under different fertilizer, tillage and residue cover treatments. The soil has a single-layered cluster structure that has a relatively good hydrologic properties and can adsorb a large amount of nutrient. 11 runoff plots were treated and monitored with respect to physical property of the soil, runoff and sediment discharge.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.24 no.11
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• pp.1-8
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• 2010

This study analyzes whether a person's visual perception differs according to the kinds of light source. Evaluations of the effects of space, color-tone and texture perception revealed that different kinds of light sources change the perception of finishing material. The perception from directly attached lamps was compared to an environment with both directly attached lamps and supplemental lighting. We found the perception changed with changes in the types of supplemental light source We compared the mean value of each perception and found that perceptions change most when incandescent lights were followed by halogen. Thus, one should account for the changes in perception that occur as a result of these changes.

• Journal of Preventive Medicine and Public Health
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• v.31 no.4 s.63
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• pp.814-827
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• 1998

In this study we analyzed the insurance claims data to investigate the medical care utilization pattern of tuberculosis patients in private sector. We selected the claims of principal or secondary diagnosis with tuberculosis from claims database of National federation of Medical Insurance, from December 1995 to November 1996. Both spell-based analysis and person-based analysis were carried out. In spell-based analysis, type and location of treatment facilities, distribution of diagnoses, number of outpatient/inpatient treatments were analyzed. Additionally in person-based analysis, number of tuberculosis patients, demographic characteristics, number of treatments per person, frequency and pattern of change in source of care were analyzed. The results were as follows 1. The number of treatments with tuberculosis was 863,641 from 1 December 1995 to 30 November 1996. The number of patients was 313.964. 2. Most of tuberculosis patients in private sector were treated in general hospital (45.8%) and clinics(42.2%) 3. About 77.7% of tuberculosis patients who were treated more than two times did not change the source of care. 18,9% of tuberculosis patients changed source of care only once. Even when we limited tuberculosis patient to those who were treated more than five times and whose treatment period were longer than six months, 94.7% of patients did not change source of care at all, or changed treatment facility only once. 4. The probability of change in source of rare was higher in pulmonary tuberculosis, in twenties, and in rural area respectively than other tuberculosis. In conclusion, healer shopping of tuberculosis patients was not serious as expected. However special attention is needed to pulmonary tuberculosis in twenties and rural area.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2010.05a
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• pp.163-164
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• 2010

• Geosystem Engineering
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• v.21 no.6
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• pp.309-317
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• 2018

We employ a three-dimensional indirect boundary element method (BEM) to simulate temperature change around an underground liquefied natural gas storage cavern. The indirect BEM (IBEM) uses fictitious heat source strength on boundary elements as basic variables which are solved from equations of boundary conditions and then used to compute the temperature change at other points in the considered problem domain. The IBEM requires evaluation of singular integration for temperature change due to heat conduction from a constant heat source on a planar (triangular) region. The singularity can be eliminated by a semi-analytical integration scheme. However, it is found that the semi-analytical integration scheme yields sharp temperature gradient for points close to vertices of triangle. This affects the accuracy of heat flux, if they are evaluated by finite difference method at these points. This difficulty can be overcome by a combination of using a direct numerical integration for these points and the semi-analytical scheme for other points distance away from the vertices. The IBEM and the hybrid integration scheme have been verified with an analytic solution and then used to the application of the underground storage.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.3
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• pp.453-457
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• 2008

We studied on the dependency of parameters which those were used to design a ballast of ICP light source. These parameters were derived from Barkhausen criterion equation about the oscillating condition of ballast. Comparing with a change of turns, we can suggest that a change of l is suitable to control a $I_p$ of an ICP light source. According to the Z-l equation, we can find an optimum rating power of ICP light sources corresponding to l.

• Microbiology and Biotechnology Letters
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• v.22 no.6
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• pp.565-570
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• 1994

The pullulan production and morphological change of Aureobasidium pullulans ATCC 9348 were investigated both in batch fermentation and in continuous fermentation. The best carbon source for pullulan production was sucrose among seven different carbon sources. The pullulan production of A. pullulans was increased with increasing the carbon to nitrogen ratio of the medium using sucrose as a carbon source. In batch fermentation, production of pullullan occurred following exhaustion of the nitrogen source from the medium. The continuous fermentation showed that the pullulan production was closely parallelled with cell growth and was most effective at a dilution rate of 0.06~0.07 hr$^{-1}$-. The ratio of yeast-like cells(blastospores) of A. pullulans increased with the increase of growth rate, and reached 100% over the growth rate of 0.07 hr$^{-1}$. The growth rate, within a certain range, affected not only on the cell morphology, but on the specific pullulan productivity of A. pullulans.

• 전기의세계
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• v.14 no.5
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• pp.20-27
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• 1965

There are several methods of speed control in induction motors. One of which is to change the frequency of source but was not used frequently because of the difficulty of frequency-change. Then, the development of frequency changer using semiconductor enables the method useful. In this paper the speed characteristics of mechanical output, secondary input torque and secondary power factor are described when the frequency of source and voltage which is proportional to the frequency of source in order to make the flux in the air gap in constant, are changed. The above characteristics are searched on the basis of the rated characteristics of the motor. Because the ratio of these is proportional to that of the secondary current or the square value of it. To get the ratio of the secondary current, a current circle diagram is introduced, and the magnitude of the ratio from this diagram is accurate and simple. Experimental results are in good agreement with theoretical predictions.

• Journal of Korea Water Resources Association
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• v.51 no.7
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• pp.585-597
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• 2018

This study aims to investigate the variation of water quality and discharge under the condition of climate change and Best Management Practices (BMPs), which is one of the reduction methods for non-point source pollution. Soil and Water Assessment Tool (SWAT) model is applied to case in Cheongmicheon watershed. The coefficients required for SWAT model were calibrated using SWAT Calibration and Uncertainty Program. Climate change is considered by using Representative Concentration Pathway (RCP) scenarios, RCP 4.5 and RCP 8.5. It is known from simulation results that the non-point source pollutant increases under the climate change scenario assuming worse condition. It is also found in this study that an appropriate application of BMPs is able to reduce the quantity and temporal variation of non-point source pollutant effectively.