• Journal of the Ergonomics Society of Korea
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• v.32 no.1
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• pp.107-115
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• 2013

Objective: The aim of this study is to identify the training requirements of new nuclear power plant by a comprehensive literature review. Background: The design of instrumental and control systems for New NPP is applied fully digitalized systems. For example, soft-control, large display panels(LDP), and an advanced alarm system were applied to the APR-1400 or SMART. Method: The NUREG-0711 and international guideline of training program was analyzed from the following four phases of SAT(Systemic Approach to Training): Analysis, Design, Development, Implementation and Evaluation. Results: To identify the requirement of training program, 'Feedback' phase was considered and each phase of SAT was classified. Conclusion: A more systematic requirement of training program is needed which considers the computerized system was applied to the new NPP. Application: The results of the publishing can be useful for standardization of the systematic training program for the operators of NPP.

• Korean Journal of Veterinary Service
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• v.30 no.2
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• pp.251-258
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• 2007

Bovine brucellosis has occurred for years in Gyeonggi province under the national test and slaughter scheme. The serum agglutination test (SAT) is a diagnostic tool to confirm the disease despite the argument on its specificity. We selected 8 farms where only one or two individuals were diagnosed as brucellosis through SAT at the primary regular herd check and isolated the causative organism and characterized the species by species-specific PCR. The pathogen isolation was successful in 6 farms out of 8 farms by microbiological culture, showing the successful rate of 75%. The isolation rate of the causative organism represents 70% from supra-mammary lymph node and 60% from uterine tissues. They were characterized as Brucella abortus biovar 1 after biotyping by PCR, showing the fragment of 498 bp. Five of 8 farms were diagnosed as brucellosis two to four times more over the intervals of two or three months. Here in this study we briefly showed the correlation of the sporadic outbreak of brucellosis tested by SAT and the isolation of the causative organism. Moreover one or two reactors against brucellosis among considerable size of herd may indicate that SAT failed to detect potentially infected individuals in the incubation stage or chronic phase of the disease.

• Journal of Aerospace System Engineering
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• v.8 no.3
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• pp.27-33
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• 2014

The CubeSat, which was first launched to verify new technologies and for educational purposes, is now widely used as an educational tool since it makes possible development of manpower through practical training to produce the satellite at low development costs. At present, research and development on the CubSat is rapidly expanding in domestic and foreign universities. As one of the final 3 teams selected in the 2013 CUBE SATELLITE CONTEST organized by the Ministry of Science, ICT and Future Planning, Chosun University is also currently conducting R & D of STEP Cube Lab, which is a CubeSat scheduled to be launched in 2015 and whose main task is to verify space-based technologies in orbit. The present paper tries to present an overview of the CubeSat of Chosun University whose development is being led by its undergraduate students, and further, introduce the strengths of the present development program for developing space experts, based on the educational achievements from the R & D.

• The Journal of the Korea institute of electronic communication sciences
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• v.6 no.5
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• pp.621-627
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• 2011

In this paper, we analysed performance for on-wafer GaN HEMT using load-pull in X-band, and studied optimum impedance point based on analysis result. We suggested method of optimum performance device by analysis of optimum impedance for solid state device on-wafer condition before packaging. The measured device is gate length 0.25um, and gate width is 400um, 800um. device 400um is performed $P_{sat}$=33.16dBm, PAE=67.36%, Gain=15.16dBm, and device 800um is performed $P_{sat}$=35.91dBm, PAE=69.23%, Gain=14.87dBm.

• Advances in aircraft and spacecraft science
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• v.6 no.5
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• pp.427-442
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• 2019

Small satellites represent an emerging opportunity to realize a wide range of space missions at lower cost and faster delivery, compared to traditional spacecraft. However, small platforms, such as CubeSats, shall increase their actual capabilities. Miniaturized electric propulsion systems can provide the satellite with the key capability of moving in space. The level of readiness of miniaturized electric propulsion systems is low although many concepts have been developed. The present research intends to build a flexible test platform for the assessment of selected small propulsion systems in relevant environment at laboratory level. Main goal of the research is to analyze the mechanical, electrical, magnetic, and chemical interactions of propulsion systems with the modern CubeSat-technology and to assess the performance of the integrated platform. The test platform is a 6U CubeSat hosting electric propulsion systems, providing mechanical, electrical and data interfaces, able to handle a variety of electric propulsion systems, thanks to the ability to regulate and distribute electric power, to exchange data according to several protocols, and to provide different mechanical layouts. The test platform is ready to start the first verification campaign. The paper describes the detailed design of the platform and the main results of the AIV activities.

• Journal of Astronomy and Space Sciences
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• v.37 no.4
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• pp.219-228
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• 2020

A CubeSat platform has become a popular choice due to inexpensive commercial off-the-shelf (COTS) components and low launch cost. However, it requires more power-efficient and higher-data rate downlink capability for space applications related to remote sensing. In addition, the platform is limited by the size, weight and power (SWaP) constraints as well as the regulatory issue of licensing the radio frequency (RF) spectrum. The requirements and limitations have put optical communications on promising alternatives to RF communications for a CubeSat platform, owing to the power efficiency and high data rate as well as the license free spectrum. In this study, we analyzed the performance of optical downlink communications compatible with CubeSat platforms in terms of data rate, bit error rate (BER) and outage probability. Mathematical models of BER and outage probability were derived based on not only the log-normal model of atmospheric turbulence but also a transmitter with a finite extinction ratio. Given the fixed slot width, the optimal guard time and modulation orders were chosen to achieve the target data rate. And the two performance metrics, BER and outage data rate, were analyzed and discussed with respect to beam divergence angle, scintillation index and zenith angle.

• 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.

• Journal of the Korean Geographical Society
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• v.50 no.1
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• pp.91-103
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• 2015

The purpose of this study is to investigate if there is any regional distribution difference in the frequency of geographical location's name mentioned on the SAT Korean geography test. The reviewed items were used for geography subject test in Korean SAT exam in between 2005 and 2015. Researchers analyzed how often a location had been mentioned in the form of maps, captions, and graphs in the national college entrance exam for 11 years. The result indicated that 42% out of the 220 items were using map and about 33% of them represented a specific region. Especially, items related with climate, industries, and local area section contained a specific area information more frequently than others. Moreover, there were 76 cities mentioned in geography subject test on Korean SAT exam during 11 years and 25 places among them were referred to more than three times. The most frequently appeared city was Seoul followed by Incheon, Daegu, Busan, Gangneung, and Jeju and this result shows that there were some regional bias in geography test on the SAT Korean exam.

• Journal of rehabilitation welfare engineering & assistive technology
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• v.11 no.3
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• pp.239-245
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• 2017

In the current study, the relationships between abdominal adipose tissue depots and skinfold thickness, body circumference and composition, and blood lipids and pressure were investigated in adolescent obese man. Total abdominal adipose tissue (TAT) and subcutaneous adipose tissue (SAT) were correlated with skinfold thickness. Especially subscapular skinfold was highly correlated with TAT and SAT, and it was found that chest skinfold was the only predictor for estimating visceral adipose tissue (VAT). Body circumference and body composition were associated with TAT and SAT, not VAT, and correlation coefficient of waist circumference was highest. On the other hand, body fat mass was highly correlated with TAT and SAT than %body fat and fat free mass. It was also shown that blood triglyceride concentration and systolic blood pressure were the only predictor for estimating VAT and SAT respectively.

• The Bulletin of The Korean Astronomical Society
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• v.39 no.1
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• pp.50.1-50.1
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• 2014

The Multi-purpose InfraRed Imaging System (MIRIS) is the main payload of Science and Technology Satellite 3 (STSAT-3), which was launched onboard Dnepr rocket from Russian Yasny Launch Base in November 2013. The MIRIS is an infrared (IR) camera, and the telescope has to be cooled down to below 200K in order to reduce thermal background noise. For the effective cooling and low-power consumption, we applied passive cooling method to the thermal design of the MIRIS. We also conducted thermal analysis and tested for the passive cooling before the launch of STSAT-3. After the launch, we have received State-of-Health (SOH) data from the satellite on orbit, including temperature monitoring results. It is important that the temperature of the telescope was shown to be cooled down to below 200K. In this paper, we present both the temperature data of the MIRIS on orbit and the thermal analysis results in the laboratory. We also compare these results and discuss the verification of the passive cooling.