• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.18 no.2_spc
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• pp.327-336
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• 2020

The high-flux advanced neutron application reactor (HANARO) is a research reactor with thermal power of 30 MW applied in various research and development using neutrons generated from uranium fission chain reaction. A degasifier tank is installed in the ancillary facility of HANARO. This facility generates gas pollutants produced owing to internal environmental factors. The degasifier tank is designed to maintain the gas contaminants below acceptable levels and is monitored using an analyzer in the gas sampling panel. If condensate water is generated and flows into the analyzer of the gas sampling panel, corrosion occurs inside the analyzer's measurement chamber, which causes failure. Condensate water is generated because of the temperature difference between the degasifier tank and analyzer when the gas flows into the analyzer. A heating system is installed between the degasifier tank and gas sampling panel to suppress condensate water generation and effectively remove the condensate water inside the system. In this study, we investigated the efficiency of the heating system. In addition, the variations in the pipe temperature and the amount of average condensate water were modeled using a wall condensation model based on the changes in the fluid inlet temperature, outside air temperature, and heating cable-setting temperature.

• 제어로봇시스템학회:학술대회논문집
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• 1991.10b
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• pp.1649-1654
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• 1991

In 1995 the VSOP satellite, which is called MUSES-B in Japan, will be launched under the VLBI Space Observatory Programme(VSOP) promoted by ISAS(Institute of Space and Astronautical Science) of Japan. We are now developing the GPS Receiver(GPSR) and On-board Orbit Determination System. This paper describes the GPS(Global Positioning System), VSOP, GPSR(GPS Receiver system) configuration and the results of the GPS system analysis. The GPSR consists of three GPS antennas and 5 channel receiver package. In the receiver package, there are two 16 bits microprocessing units. The power consumption is 25 Watts in average and the weight is 8.5 kg. Three GPS antennas on board enable GPSR to receive GPS signals from any NAVSTARs(GPS satellites) which are visible. NAVSATR's visibility is described as follows. The VSOP satellite flies from 1, 000 km to 20, 000 km in height on the elliptical orbit around the earth. On the other hand, the orbit of NAVSTARs are nearly circular and about 20, 000 km in height. GPSR can't receive the GPS signals near the apogee, because NAVSTARs transmit the GPS signals through the NAVSTAR's narrow beam antennas directed toward the earth. However near the perigee, GPSR can receive from 12 to 15 GPS signals. More than 4 GPS signals can be received for 40 minutes, which are related to GDOP(Geometric Dillusion Of Precision of selected NAVSTARs). Because there are a lot of visible NAVSTARs, GDOP is small near the perigee. This is a favorqble condition for GPSR. Orbit determination system onboard VSOP satellite consists of a Kalman filter and a precise orbit propagator. Near the perigee, the Kalman filter can eliminate the orbit propagation error using the observed data by GPSR. Except a perigee, precise onboard orbit propagator propagates the orbit, taking into account accelerations such as gravities of the earth, the sun, the moon, and other acceleration caused by the solar pressure. But there remain some amount of calculation and integration errors. When VSOP satellite returns to the perigee, the Kalman filter eliminates the error of the orbit determined by the propagator. After the error is eliminated, VSOP satellite flies out towards an apogee again. The analysis of the orbit determination is performed by the covariance analysis method. Number of the states of the onboard filter is 8. As for a true model, we assume that it is based on the actual error dynamics that include the Selective Availability of GPS called 'SA', having 17 states. Analytical results for position and velocity are tabulated and illustrated, in the sequel. These show that the position and the velocity error are about 40 m and 0.008 m/sec at the perigee, and are about 110 m and 0.012 m/sec at the apogee, respectively.

• Journal of the Korean Institute of Intelligent Systems
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• v.25 no.1
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• pp.7-14
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• 2015

To implement an automatic picking system (APS) in distribution center with high precision and high dynamics, this paper presents a high gain observer-based robust speed controller design for a linear induction motor (LIM) drive. The force disturbance as well as the mechanical parameter variations such as the mass and friction coefficient gives a direct influence on the speed control performance of APS. To guarantee a robust control performance, the system uncertainty caused by the force disturbance and mechanical parameter variations is estimated through a high gain disturbance observer and compensated by a feedforward manner. While a time-varying disturbance due to the mass variation can not be effectively compensated by using the conventional disturbance observer, the proposed scheme shows a robust performance in the presence of such uncertainty. A Simulink library has been developed for the LIM model from the state equation. Through comparative simulations based on Matlab - Simulink, it is proved that the proposed scheme has a robust control nature and is most suitable for APS.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.37 no.12
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• pp.1175-1183
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• 2013

Even if some CFD software developers and its users think that a state-of-the-art CFD software can be used to reasonably solve at least single-phase nuclear reactor safety problems, there remain limitations and uncertainties in the calculation result. From a regulatory perspective, the Korea Institute of Nuclear Safety (KINS) is presently conducting the performance assessment of commercial CFD software for nuclear reactor safety problems. In this study, to examine the prediction performance of commercial CFD software with the porous model in the analysis of the scale-down APR (Advanced Power Reactor Plus) internal flow, a simulation was conducted with the on-board numerical models in ANSYS CFX R.14 and FLUENT R.14. It was concluded that depending on the CFD software, the internal flow distribution of the scale-down APR was locally somewhat different. Although there was a limitation in estimating the prediction performance of the commercial CFD software owing to the limited amount of measured data, CFX R.14 showed more reasonable prediction results in comparison with FLUENT R.14. Meanwhile, owing to the difference in discretization methodology, FLUENT R.14 required more computational memory than CFX R.14 for the same grid system. Therefore, the CFD software suitable to the available computational resource should be selected for massively parallel computations.

• Korean Journal of Human Ecology
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• v.8 no.2
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• pp.255-273
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• 1999

The purpose of this study was to examine the relationship between characteristics of personality and respondent characteristics of Kinetic Family Drawing for young children. The subjects were 170 children(110 boys and 60 girls). The personal interview contained Personality Characteristic Test for young children(In-Sub Song, 1993) and Kinetic Family Drawing Test(Burns and Kaufman, 1982). Results of the test were analyzed by t-test and ANOVA by SAS program. Results are followings. First, chileren's sex and the general tendency of personal characteristic showed significant difference in the emotional personality among 4 personality characteristics. Girls show more positive tendency than boys in moral, physical, appearance and feature which expressed personal feeling and emotion. Also, girls showed more positive tendency than boys in personal characteristic which showed physical ability. Second, Children's sex and individual characteristic in Kinetic Family Drawing respondent characteristic showed significant difference in own's arm length. Also, Using a rare of paper and chapter 1 of the power among the family showed significant difference in styles and symbols. The boys drew lengther arms compared with their height than the girls. The girls were less complicative, anxious, comparative and aggressive for their family. Third, As a result of the study about the relationship between 4 personal characteristics of children and individual's behavior in Kinetic Family Drawing respondent characteristic, the significant difference is showed in academic personality and social personality had higher completion of their father's feature and drew bigger feet. In socal personality, negative behavior than positive children. Fourth, As a result of the study about the relationship between 4 personal characteristics of children and individual's characteristic, the significant difference were found in academic personality, social personality, family personality and emotional personality. Children with negative academic personality drew longer arms than children with positive academic personality, social personality and family personality. Also, Children with negative emotional personality drew more siblings than children with positive emotional personality. Fifth, The academic personality and the social personality had significant difference in the relationship between 4 personal characteristics of children and dynamics. In social personality, normal children were more tendencious to look at the important person with their mother's direction than positive children. Sixth, In terms of the relationship between 4 personal characteristics of children and mode, academic personality and family personality showed significant difference. Children with negative academic personality used more edge of papers than children with positive academic personality and children with positive academic personality and children with negative family personality fold more papers than children with positive family personality. At last, there were no significant difference between 4 personal characteristics of children and styles as well as symbols.

• Journal of Microbiology and Biotechnology
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• v.19 no.12
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• pp.1656-1664
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• 2009

Bioaugmentation of bioreactors focuses on the removal of numerous organics, with little attention typically paid to the maintenance of high and stable nitrite accumulation in partial nitrification. In this study, a bioaugmented membrane bioreactor (MBR) inoculated with enriched ammonia-oxidizing bacteria (AOB) was developed, and the effects of dissolved oxygen (DO) and temperature on the stability of partial nitrification and microbial community structure, in particular on the nitrifying community, were evaluated. The results showed that DO and temperature played the most important roles in the stability of partial nitrification in the bioaugmented MBR. The optimal operation conditions were found at 2-3 mgDO/l and $30^{\circ}C$, achieving 95% ammonia oxidization efficiency and nitrite ratio ($NO_2^-/{NO_x}^-$) of 0.95. High DO (5-6 mg/l) and low temperature ($20^{\circ}C$) had negative impacts on nitrite accumulation, leading to nitrite ratio drop to 0.6. However, the nitrite ratio achieved in the bioaugmented MBR was higher than that in most previous literatures. Denaturing gradient gel electrophoresis (DGGE) and fluorescence in situ hybridization (FISH) were used to provide an insight into the microbial community. It showed that Nitrosomonas-like species as the only detected AOB remained predominant in the bioaugmented MBR all the time, and coexisted with numerous heterotrophic bacteria. The heterotrophic bacteria responsible for mineralizing soluble microbial products (SMP) produced by nitrifiers belonged to the Cytophaga-Flavobacterium-Bacteroides (CFB) group, and $\alpha$-, $\beta$-, and $\gamma$- Proteobacteria. The fraction of AOB ranging from 77% to 54% was much higher than that of nitrite-oxidizing bacteria (0.4-0.9%), which might be the primary cause for the high and stable nitrite accumulation in the bioaugmented MBR.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.3
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• pp.673-680
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• 2017

sump pump is a system that draws in water that is stored in a dam or reservoir. They are used to pump large amounts of water for cooling systems in large power plants, such as thermal and nuclear plants. However, if the flow and sump pump ratio are small, the flow rate increases around the inlet port. This causes a turbulent vortex or swirl flows. The turbulent flow reduces the performance and can cause failure. Various methods have been devised to solve the problem, but a correct solution has not been found for low water level. The most efficient solution is to install an anti-vortex device (AVD) or increase the length of the sump inlet, which makes the flow uniform. This paper presents a computational fluid dynamics (CFD) analysis of the flow characteristics in a sump pump for different sump inlet lengths and AVD types. Modeling was performed in three stages based on the pump intake, sump, and pump. For accurate analysis, the grid was made denser in the intake part, and the grid for the sump pump and AVD were also dense. 1.2-1.5 million grid elements were generated using ANSYS ICEM-CFD 14.5 with a mixture of tetra and prism elements. The analysis was done using the SST turbulence model of ANSYS CFX14.5, a commercial CFD program. The conditions were as follows: H.W.L 6.0 m, L.W.L 3.5, Qmax 4.000 kg/s, Qavg 3.500 kg/s Qmin 2.500 kg/s. The results of analysis by the vertex angle and velocity distribution are as follows. A sump pump with an Ext E-type AVD was accepted at a high water level. However, further studies are needed for a low water level using the Ext E-type AVD as a base.

• Korea Journal of Hospital Management
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• v.5 no.1
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• pp.232-271
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• 2000

The introduction of a team system to any organization is usually to improve that organizations dynamics, by increasing the proper adaptation to rapidly changing environments, by reducing approval procedures, and by promoting power authorization. In this regard, this study was carried out in an attempt to determine (1) whether or not the introduction of a team system can be as effective in hospital organizations as it has been in business organizations, and (2) what behavior factors influence such effectiveness. For the current study, questionnaires were distributed to the employees of a university hospital in Pusan. Four hundred eighty three of them(94.7%) were retrieved and analyzed through statistical processes. The three types of variables that were found to influence team effectiveness were: (1) independent variables of team organization characteristics, such as communication, organizational atmosphere, leadership and team knowledge, (2) intervening variables of team organization characteristics. such as job autonomy, technological variety, task subjectivity, task feedback and task importance, and(3) the dependent variables of team level effectiveness, such as job satisfaction and commitment to team organization. The gathered data were processed by using the 6.12 version of the statistical program SAS(Statistical Analysis System), and the reliance coefficient of those measured variables was then evaluated as an average of 0.78. The influence of team level effectiveness was analyzed by using multiple regression analysis. These differences in effectiveness were then analyzed on the basis of related mean values, while the differences among demo-sociological characteristics were analyzed by using the dispersion analysis(ANOVA) and the t-test. The results of the study can be summarized by the following. First, regarding the relationship between team organization characteristics and team level effectiveness, all of the factors including communication, organizational atmosphere, leadership and team knowledge were found to have a significant influence on effectiveness. Second, the factors of team job characteristics, such as technological variety, task importance and job autonomy, had significant effects on job satisfaction and organizational commitment among the teams members. Team level effectiveness was generally high, while team job satisfaction was higher the teams organizational commitment. Third, regarding the demo-sociological characteristics, team level effectiveness was found to be higher among those who were older, who had more job experience, and who had a higher position. Comparing the differences among job types, the effectiveness was relatively higher in the fields of nursing and administration/management then in other fields. Further study should be done towards the setting of variables for characteristics of hospital organization, developing suitable methods of measurement, and researching individual level effectiveness.

• Journal of the Korean Society of Radiology
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• v.10 no.1
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• pp.53-58
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• 2016

March 11, 2011 Fukushima nuclear power plant accident has occurred, the last four years, his is the current state of anxiety remains on the consumer. Therefore, 2015 the current progress continues to have continued research for the purpose of resolving the insecurity of fishery in the country. We measured the radiation of the origin of fishery products, by 2015, research was carried out through a number of references to get additional data or studies that influence this to some degree. Create a consumer and one for the seller for the survey to find out the thoughts of both consumers and sellers on fisheries was to create the statistics by direct survey in 2014 year survey meter using PM1405 equipment dynamics of several species of aquatic origin in accordance with the (Taiwan, China, Russia), mackerel, pomfret, hairtail, saury, shrimp, squid measurements of radiation were investigated. The measurement in 2014 was $0.043{\sim}0.073{\mu}Sv/h$. The seller influenced the survey (90%) on fishery products sales, consumer safety, without this fishery (90%), radioactive contamination very high (28%) and the polarization was not as nearly 72%. The study of the stability of the radiation determined by the radiation levels of the aquatic marine products in a comparison the radiation levels result was determined in ICRP below the standard value (1 mSv/y).

• Korean Journal of Applied Biomechanics
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• v.21 no.1
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• pp.31-38
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• 2011

This study aimed to determine the effects of the blockage of visual feedback on joint dynamics of the lower extremity. Fifteen healthy male subjects(age: $24.1{\pm}2.3\;yr$, height: $178.7{\pm}5.2\;cm$, weight: $73.6{\pm}6.6\;kg$) participated in this study. Each subject performed single-legged landing from a 45 cm-platform with the eyes open or closed. During the landing performance, three-dimensional kinematics of the lower extremity and ground reaction force(GRF) were recorded using a 8 infrared camera motion analysis system (Vicon MX-F20, Oxford Metric Ltd, Oxford, UK) with a force platform(ORG-6, AMTI, Watertown, MA). The results showed that at 50 ms prior to foot contact and at the time of foot contact, ankle plantar-flexion angle was smaller(p<.05) but the knee joint valgus and the hip flexion angles were greater with the eyes closed as compared to with the eyes open(p<.05). An increase in anterior GRF was observed during single-legged landing with the eyes closed as compared to with the eyes open(p<.05). Time to peak GRF in the medial, vertical and posterior directions occurred significantly earlier when the eyes were closed as compared to when the eyes were open(p<.05). Landing with the eyes closed resulted in a higher peak vertical loading rate(p<.05). In addition, the shock-absorbing power decreased at the ankle joint(p<.05) but increased at the hip joints when landing with the eyes closed(p<.05). When the eyes were closed, landing could be characterized by a less plantarflexed ankle joint and more flexed hip joint, with a faster time to peak GRF. These results imply that subjects are able to adapt the control of landing to different feedback conditions. Therefore, we suggest that training programs be introduced to reduce these injury risk factors.