• Journal of the Korean Society of Manufacturing Process Engineers
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• v.11 no.4
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• pp.1-6
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• 2012

This paper addresses the issue of Renewable Energy for Electricity Storage device is one of the NAS (Sodium-Sulfur) battery will be about the module. For safety reasons, not the actual battery cells using a dummy cell in the module's operating temperature setting to examine the characteristics of the insulation vacuum of the wall temperature and external temperature changes measured over time. Upper and lower boundaries of the wall vacuum insulation characteristics cotton C intervals over time, average $5^{\circ}C$, but the temperature is rising, 4C section with little temperature change did not occur. On the other hand, about $3^{\circ}C$ in section 4D, and it was confirmed that the temperature rises. Wall vacuum insulation characteristics over time to look at the experiments and measurements are described.

• Progress in Superconductivity and Cryogenics
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• v.9 no.3
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• pp.26-31
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• 2007

In recent years. YBCO coated conductor (CC) called as second generation HTS (high temperature superconducting) wire has been developed as a suitable material for resistive superconducting fault current limiter (SFCL). For designing the SFCL. the required length of superconducting wire is inverse proportional to the maximum temperature reached when a fault occurs. Since the required length strongly affects a manufacturing cost, it is the most important parameter to determine the maximum temperature reached. It is necessary to observe the repetitive over-current characteristics of HTS wire. This paper attempts to measure the variation of critical current of YBCO CC after repetitive over-current pulse. No degradation of the critical current of CC sample was observed by applying 100 times over-current pulse which makes temperature above 400 K after 100ms. This study can be useful in designing optimally resistive SFCL employing YBCO CC. The maximum permissible temperature can be set to 400K. so wire length could be reduced by 30% compared in case of 300K-criterion.

• Proceedings of the IEEK Conference
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• 2003.11c
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• pp.309-312
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• 2003

In this study, the electrical characteristic of Symmetric high voltage MOSFET (SHVMOSFET) for display driver IC were investigated. Measurement data are taken over range of temperature (300K-400K) and various extended drain length. In high temperature condition(>400K), drain current decreased over 20％, and specific on-resistance increased over 30％ in comparison with room temperature.

• Proceedings of The Korean Society of Agricultural and Forest Meteorology Conference
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• 2016.09a
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• pp.25-28
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• 2016

Recently, because of the weather forecasts through the low-resolution data has been limited, the demand of the high-resolution data is sharply increasing. Therefore, in this study, we restore the ultra-high resolution synthetic precipitation and temperature data for 2000-2014 due to small-scale topographic effect using the QPM (Quantitative Precipitation Model)/QTM (Quantitative Temperature Model). First, we reproduce the detailed precipitation and temperature data with 1km resolution using the distribution of Automatic Weather System (AWS) data and Automatic Synoptic Observation System (ASOS) data, which is about 10km resolution with irregular grid over South Korea. Also, we recover the precipitation and temperature data with 1km resolution using the MERRA reanalysis data over North Korea, because there are insufficient observation data. The precipitation and temperature from restored current climate reflect more detailed topographic effect than irregular AWS/ASOS data and MERRA reanalysis data over the Korean peninsula. Based on this analysis, more detailed prospect of regional climate is investigated.

• Journal of Korean Academy of Nursing
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• v.4 no.2
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• pp.93-106
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• 1974

The purposes of this study are to identify the necessity of utilization of electric thermometer, to determine the difference of clinical thermometers to reach maximum or optimum temperature, and to determine the length of time necessary for temperature taking, with Fahrenheit thermometer, electric thermometer, Yu Ⅱ centigrade thermometer, and Kuk ll centigrade thermometer. The first and second comparative Experiments were' conducted from August 25 through September 30, 1973. In the first experiment, Fahrenheit thermometer, which had been accurately teated two times, and electric thermometer have been utilized. These two kinds of thermometers were inserted simultaneously under the central area of the tongue and the mouth kept closed while thermometers were in place. All temperature readings were done at one minute interval until leaching-maximum temperature. These procedures were repeated one hundred times and the data were-analyzed statistically by means of the t-test. In the second experiment, Fahrenheit thermometer, which had been accurately tested two. times, Yu Ⅱ centigrade thermometer, and Kuk Ⅱ centigrade thermometer have been utilized. These three kinds of thermometers were inserted simultaneously under the central area of the. tongue and the mouth kept closed while thermometer were in place. All temperature readings were done at one minute interval until reaching maximum temperature. These procedures were. repeated one hundred times and the data were analyzed statistically by means of the F-ratio Under the eight hypotheses designed for this study, the findings obtained are as follows: 1. There were no significant differences in the maximum temperature between Fahrenheit thermometer and electric thermometer. The mean maximum temperature for Fahrenheit thermometers was 37.06℃ and for electric thermometer was 37.09℃. 2. The placement time to reach maximum temperature taken by Fahrenheit thermometer was significantly shorter than that by electric thermometer. The mean placement time for Fahrenheit thermometers was 4.04 minutes, for electric thermometer was 5.52 minutes. In the case of Fahrenheit thermometers, 45 to 77 percent after 3 to 5 minutes, over 90 Percent after 7 minutes, and 100 percent after 10 minutes, had reached optimum temperature. When the electric thermometer was used, 23 to 54 percent after 3 to 5 minutes, over 90 percent after 9 minutes, and 100 percent after 12 minutes, had reached optimum temperature. 5. There ware no significant differences in the maximum temperature among Fahrenheit thermometer, Yu Ⅱ centigrade thermometer, and Kuk Ⅱ centigrade thermometer. The mean maximum temperature for Fahrenheit thermometers was 36.67℃, for Yu Ⅱ centigrade thermometer, was 33.73℃, and for Kuk Ⅱ centigrade thermometers was 37.76℃. 6. There were no significant differences in placement time to reach maximum temperature among Fahrenheit thermometer, Yu Ⅱ centigrade Thermometer, and Kuk Ⅱ centigrade thermometer. The mean placement time (or Fahrenheit thermometers was 7.77 minutes, for Yu Ⅱ centigrade thermometers was 7.25 minutes, and Kuk Ⅱ centigrade thermometers was 7.25 minutes. In the case of Fahrenheit thermometers, 8 to 24 percent after 3 to 5 minutes, over 90 percent after 11 minutes, and 100 percent after 13 minutes, had reached maximum temperature. When the Yu Ⅱ centigrade thermometer was used, 10 to 27 percent after 3 to 5 minutes, over 90 percent after 11 minutes, an8 103 percent after 13 minutes, had reached maximum temperature. When the Kuk Ⅱ centigrade thermometer was used, 11 to 27 Percent after 3 to 5 minutes, over 90 percent after 11 minutes, and 100 percent after 12 minutes, had reached maximum temperature. 7. There were no significant differences in the optimum temperature(the maximum temperature minus 0.1℃) among fahrenheit thermometer, Yu Ⅱcentigrade thermometer, and Kuk Ⅱ centigrade thermometer. The mean optimum temperature for Fahrenheit thermometers was 36.60℃, for Yu Ⅱ centigrade thermometers was 36.69℃, and Kuk Ⅱ centigrade thermometers was 36.69℃. 8. There were no significant differences in placement time to reach optimum temperature among Fahrenheit thermometer, Yu Ⅱ centigrade thermometer, and Kuk Ⅱ centigrade thermometer The mean placement time for Fahrenheit thermometers was 5.70 minutes, for Yu Ⅱ centigrade thermometers was 5.54 minutes, and for Kuk Ⅱ centigrade thermometers was 5.28 minutes. In the case of Fahrenheit thermometers, 21 to 49 percent after 3 to 5 minutes, over 90 percent after 9 minutes, and 100 percent after 12 minutes, had reached optimum temperature. When the Yu Ⅱ centigrade thermometer was used, 23 to 51 percent after 3 to 5 minutes over 90 percent after 10 minutes, and 100 percent after 12 minutes, had reached optimum temperature. When the Kuk Ⅱ centigrade Thermometer was used, 23 to 57 Percent after 3 to 5 minutes, over 90 percent after 9 minutes, and 100 Precent after 11 minutes, had reached optimum temperature.

• Proceedings of the IEEK Conference
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• 2005.11a
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• pp.579-582
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• 2005

In this study, the electrical characteristic of asymmetric high voltage MOSFET (AHVMOSFET) for display IC was investigated. Measurement data are taken over range of temperature (300K-400K) and various extended drain length, and gate oxide thickness ($175{\AA}$, $350{\AA}$). In high temperature condition, drain current decreased over 30% and max transconductance deceased over 40%, and specific on-resistance increased over 30% in comparison with room temperature.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• v.18 no.3
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• pp.245-256
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• 2014

This work is focused on the boundary layer and heat transfer characteristics of hydromagnetic flow over a stretching sheet with variable thickness. Steady, two dimensional, nonlinear, laminar flow of an incompressible, viscous and electrically conducting fluid over a stretching sheet with variable thickness and power law velocity in the presence of variable magnetic field and variable temperature is considered. Governing equations of the problem are converted into ordinary differential equations utilizing similarity transformations. The resulting non-linear differential equations are solved numerically by utilizing Nachtsheim-Swigert shooting iterative scheme for satisfaction of asymptotic boundary conditions along with fourth order Runge-Kutta integration method. Numerical computations are carried out for various values of the physical parameters and the effects over the velocity and temperature are analyzed. Numerical values of dimensionless skin friction coefficient and non-dimensional rate of heat transfer are also obtained.

• Journal of Institute of Control, Robotics and Systems
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• v.6 no.6
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• pp.500-505
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• 2000

This paper deals with wafer temperature uniformity control essential in rapid thermal processing (RTP). One of the important control objectives of RTP is to keep the temperature over the wafer surface as uniformly as possible. For this, a discrete time state equation around the operating point is first identified by using the subspace fitting method, and a multivariable LQG(Linear Quadratic Gaussian) controller is designed based on the identified model. Simulation and experimental results show improvement in temperature uniformity over the conventional PID method.

• Atmosphere
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• v.31 no.1
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• pp.61-71
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• 2021

The relationship between the Arctic Oscillation (AO) and surface air temperature (SAT) over Korea is re-examined using the long-term observation and reanalysis datasets for the period of December 1958 to February 2020. Over the entire period, Korean SAT is positively correlated with the AO index with a statistically significant correlation coefficient, greater than 0.4, only in the boreal winter. It is found that this correlation is not static but changes on the decadal time scale. While the 15-year moving correlations are as high as 0.6 in 1980s and 1990s, they are smaller than 0.3 in the other decades. It is revealed that this decadal variation is partly due to the AO structure change over the North Pacific. In the period of 1980s-1990s, the AO-related sea level pressure fluctuation is strong and well defined over the western North Pacific and the related temperature advection effectively changes the winter SAT over Korea. In the other periods, the AO-related circulation anomaly is either weak or mostly confined within the central North Pacific. This result suggests that Korean SAT-AO index relationship, which becomes insignificant in recent decades is highly dependent on mean flow change in the North Pacific.

• Atmosphere
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• v.28 no.4
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• pp.383-392
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• 2018

This study investigates synoptic characteristics of cold surges over South Korea during winter season (December-February). A total of 63 cold events are selected by quantile regression analysis using daily mean temperature observations from 11 KMA stations for 38 years (1979/80-2016/17). Large-scale pressure pattern during the cold surges is well characterized by high over Siberia and low over Aleutian regions, which elucidates cold advection over the Korean peninsula. However, the large-scale pattern cannot successfully explain the observed sudden decrease of temperature during the cold surges. Composite analyses reveal that a synoptic-scale cyclone developing over the northern Japan is a key feature that significantly contribute to the enhancement of cold advection by increasing pressure gradient over the Korean peninsula. Enhanced sensible and latent heat fluxes are observed over the southern ocean of Korea and Japan during the cold surges due to temperature and humidity differences between the near surface and the lower atmosphere over the ocean. The evaporated water vapor transported toward the center of the surface cyclone and condenses in the lower-to-middle troposphere. The released energy likely promotes the development of the surface cyclone by inducing positive PV near the surface of the heating region.