• International Journal of Advanced Culture Technology
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• v.8 no.1
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• pp.19-25
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• 2020

This article describes the automated incubator designs for white mushrooms growing. Mongolia has a very long and cold winter, so the process of growing mushrooms is short. Therefore, we aim to design an automated incubator system that has created a favorable artificial environment for mushroom growing by examining the necessary conditions for mushroom growing. This system was designed to be able to hold for some time the required levels of soil moisture, air humidity, soil temperature, air temperature, and CO2 levels. This article presents the results of a system-based experiment that allows you to grow mushrooms for 30 days without human interference.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.11a
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• pp.319-320
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• 2005

This paper describes the principles and structures of an expert system for arrester diagnosis. The expert system analyzes and decides the arrester condition by total leakage current, its harmonic component, and temperature because the deterioration of arresters appeared in an increase of leakage current and surface temperature of it. Additionally, influence of system voltage harmonics and ambient temperatures on leakage current changes were considered in the design. The expert system is consisted of a data acquisition module and a computer for monitoring. The acquired analog data are digitalized and transmitted to the computer by an optical link which is free from interference.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.11a
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• pp.268-271
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• 2002

The goal of the research is to study and describe a new stressed state of High Temperature Superconducting (High-Tc) YBCO Films, to create of SQUIDs (Superconducting Quantum Interference Device) on the bases of these Films with maximal sensitivity. The experimental investigation of the stressed films grown by laser ablation method and its properties, the fabrication of the dc-SQUIDs with maximal sensitivity on the bases of the stressed YBCO films were carried out. The stressed film having the value of the critical current density $J_{c}=3{\cdot}10^{5}A/cm^{2}$ was the more stable than others.

• Journal of Institute of Control, Robotics and Systems
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• v.9 no.8
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• pp.647-650
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• 2003

PLC (Power Line Communication) is the communication method using the existing power line installed in houses and offices to convert and transmit high frequency communication signal from tens of KHz to tens of MHz, and receive the filtered signal using high frequency filter The advantage of PLC is that PLC uses the existing power line installed in houses and offices so it does not require separate power line. Easy and convenient access using electric outlets is another advantage of PLC. However, PLC has some disadvantages such as limited transmission power, high load interference and noise, variable signal attenuation, characteristic of impedance, and selective possibility of frequency property. We designed the boiler temperature control system unit by using the PLC modem. We can avoid unnecessary heating of separate temperature control unit, and save the cost accordingly control stability of the proposed system is proven through the experiment.

• Journal of Magnetics
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• v.22 no.1
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• pp.1-6
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• 2017

Magnetic properties of CoPt nanoparticles (average size = 2.1 nm) encapsulated in synthesized protein shell have been investigated with SQUID (Superconducting Quantum Interference Device) magnetometer and analyzed by the recently developed non-equilibrium magnetization calculation by our group [T. H. Lee et al., Phys. Rev. B 90, 184411 (2014)]. Field dependence of magnetization measured at 2 K was successfully analyzed with modified Langevin function. In addition, small hysteresis loops having the coercive field of 890 Oe were observed at 2 K. Temperature dependence of magnetization has been measured with zero field cooled (ZFC) and field cooled (FC) protocol with slightly modified sequence in accordance with non-equilibrium magnetization calculation. The analysis on the M vs. T data revealed that the anisotropy energy barrier distribution is found to be very different from the log-normal distribution found in a size distribution. Zero temperature coercive field and Bloch coefficient have also been extracted from the analysis and the validity of those values is checked.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09a
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• pp.191-192
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• 2006

The deformation under radial pressure of rectangular dies for metal powder compaction has been investigated by FEM. The explored variables have been: aspect ratio of die profile, ratio between diagonal of the profile and die height, insert and ring thickness, radius at die corners, interference, different insert materials, i. e. conventional HSS, HSS from powders, cemented carbide (10% Co). The analyses have ascertained the unwanted appearance of tensile normal stress on brittle materials, also "at rest", and even some dramatic changes of stress patterns as the die height increases with respect to the rectangular profile dimensions. Different materials behave differently, mainly due to difference of thermal expansion coefficients. Profile changes occur when the dies are heated up to the temperature required for warm compaction. The deformation patterns depend on compaction temperature and thermal expansion coefficients.

• Bulletin of the Korean Chemical Society
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• v.9 no.2
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• pp.106-108
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• 1988

The effects of surfactants, CTAB, SDS, and TX-100, on the fluorescence emission intensity of Be-morin complex was studied in terms of pH, temperature, added electrolyte, and concentration of surfactants. The ionic surfactants decreased the fluorescence intensity of the complex. However, the addition of TX-100 caused a substantial increase in the fluorescence intensity without spectral shift, by which means the detection limit of Be was obtained to be 0.3 ppb. Optimum pH for Be determination was near 9.6 and the fluorescence intensity showed a continuous decline with the increase of temperature. Nitrate ion lowered the fluorescence intensity considerably. Mechanism of the interference remains to be elucidated.

• Korean Journal of Optics and Photonics
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• v.23 no.4
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• pp.159-166
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• 2012

We have developed a daytime measuring rotational Raman LIDAR system for temperature measurement. To decrease the background signal from sunlight, we have designed and installed narrow band (0.5 nm) and high rejection ($10^{-6}$) rate band pass filter system using a grating and an interference filter. We calibrated our system by comparing our horizontal temperature profile and KMA (Korea Meteorological Administration) data. We have found that our temperature profile has a good correlation with KMA data within our theoretically expected variance. And we have used these calibration values in obtaining a vertical temperature distribution. To check our system, we also have compared our vertical temperature data with US standard atmospheric temperature profile. We also have compared our temperature profile with sonde data.

• Current Optics and Photonics
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• v.2 no.1
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• pp.15-22
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• 2018

To measure atmospheric temperature, water vapor, and aerosol simultaneously, an efficient multi-function Raman lidar using an ultraviolet-wavelength laser has been developed. A high-performance spectroscopic box that utilizes multicavity interference filters, mounted sequentially at small angles of incidence, is used to separate the lidar return signals at different wavelengths, and to extract the signals with high efficiency. The external experiments are carried out for simultaneous detection of atmospheric temperature, water vapor, and aerosol extinction coefficient in Beijing, under clear and hazy weather conditions. The vertical profiles of temperature, water vapor, and aerosol extinction coefficient are analyzed. The results show that for an integration time of 5 min and laser energy of 200 mJ, the mean deviation between measurements obtained by lidar and radiosonde is small, and the overall trend is similar. The statistical temperature error for nighttime is below 1 K up to a height of 6.2 km under clear weather conditions, and up to a height of 2.5 km under slightly hazy weather conditions, with 5 min of observation time. An effective range for simultaneous detection of temperature and water vapor of up to 10 km is achieved. The temperature-inversion layer is found in the low troposphere. Continuous observations verify the reliability of Raman lidar to achieve real-time measurement of atmospheric parameters in the troposphere.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.3
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• pp.1263-1269
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• 2012

This paper is the research on the heated CWDM optical transmitter for the wavelength compensation at the low temperature. In general, the wavelength deviation of DFB laser is around 0.1 nm/C. The wavelength of DFB laser shifts to longer(shorter) wavelength according to the temperature increase(decrease). Typical CWDM optical communication network has 20 nm channel spacing from reference center wavelength per each channel. There is some limitation problem in the range of operating temperature due to the channel interference. For solving the limited temperature range problem, especially at the low temperature, we use the heater on the DFB laser. As a result, we could realize the CWDM optical transmitter to meet +/-6.5 nm from reference center wavelength in the range of temperature at $-40{\sim}+85^{\circ}C$, which is applicable to the industrial field.