• Journal of the Korean Society of Radiology
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• v.13 no.3
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• pp.433-438
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• 2019

The medical institutions use radiation generating devices and radioactive isotopes to diagnose and treat patients. The patient transporter performs work in an environment that is more likely to be exposed to radiation when compared with the general public, such as inevitably entering the radiation management area for patient transfer, or transferring the isotope-administered patient at a short distance. For this reason, we conducted a study to determine the degree of exposure of the patient transporter. The 12 patient transporters working at Incheon A General Hospital are eligible. From April 1, 2019 to April 30, 2019, the dosimeter was used in the chest for one month and the accumulated dose was measured. The dosimeter used was a Optically Stimulated Luminescence Dosimetry (OSLD) and the dose reading was OSLD Microstar Reading System. As a result of cumulative dose measurement for one month, the average of the deep dose was 0.13 mSv and the surface dose was 0.13 mSv, and the cumulative dose for one month was multiplied by 12 to estimate the cumulative dose expectation As a result, the average of the deep dose and the surface dose were 1.52 mSv and 1.51 mSv, respectively. It is necessary to classify the patient transporter as a frequent visitor in order to measure and manage the exposure dose, increase the knowledge of protection against radiation through education and training, and prevent radiation trouble through medical examination.

• Journal of Industrial Convergence
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• v.21 no.4
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• pp.165-170
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• 2023

There are cases where the mobility impaired have difficulty moving from the moment they leave the house. If guardians also do not have time to entrust their families, who are socially disadvantaged, to a shelter, the guardian has no choice but to check directly in order to know the location of the guardian. The AI home care solution was designed to relieve the anxiety and labor of caregivers and to provide convenience for protection facility officials and users. If more facilities distribute and use services free of charge to non-profit foundations and protective facilities, the concern of guardians will be reduced, and the burden of facility officials who have to manage facility users will be reduced. In this paper, we provide emergency notification services to guardians in the event of an emergency as well as location and status alarms for guardians, which are all data related to movement, in consideration of the mobility vulnerable. Furthermore, it is necessary to provide a service function that recommends the optimal route using a navigation function to ease the convenience and burden of facility officials. It is necessary to alleviate anxiety by providing necessary information to the guardian, such as the location of the shuttle used by the mobile weak and the time of getting on and off. In addition, while providing services for free, the goal is to improve the quality of service for facility managers and the quality of service for the mobility weak.

• Journal of Science Education
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• v.47 no.2
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• pp.139-153
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• 2023

This study aimed to investigate the effect of environmental education programs using action learning on elementary school students' environmental literacy and self-efficacy. To this end, an environmental education program using action learning was applied to 22 sixth graders of 'A' Elementary School in Busan. The results of this study were as follows. First, environmental education programs using action learning were effective in improving the environmental literacy of elementary school students. After implementing the environmental education program using action learning, students' environmental values, cognitive, and procedural ability changed positively. Environmental issues awareness and ecological knowledge improved, and there was a significant increase in environmental behavior and environmental function. Second, environmental education programs using action learning were effective in enhancing the self-efficacy of elementary school students. After implementing environmental education programs using action learning, students' confidence in problem solving and their ability to judge their behaviors improved. Third, elementary school students showed active participation and interest when conducting environmental education programs using action learning. Students have become open to protecting the environment when they find problems, devise solutions, and practice them. After reflection, it was confirmed that students' immersion and satisfaction in class were high as a solution was reached, leading to efforts to sell items they did not use and donate profits to environmental protection organizations.

• The Journal of the Korea institute of electronic communication sciences
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• v.18 no.3
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• pp.465-474
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• 2023

As the effective use and strong protection of an organization's information resources are recognized as a condition for the growth of an organization, they are increasing technological and policy investments in IS(information security). However, information exposure can occur from external invasions such as hacking and incidents related to misuse and abuse by insiders. This study proposes a mechanism that considers the organizational environment and individual characteristics from the viewpoint of promoting employees' IS participation activities. In other words, the study presents the complex effects of organizational environmental factors (ethical leadership, IS collaborative communication) and personal factors (person-organization fit) on organization trust and IS voice behavior. We surveyed office workers who asked for IS-related business activities and tested hypotheses using 422 samples. As a result, ethical leadership influenced organization trust through collaborative communication, and organization trust strengthened IS voice behavior by having an interaction effect with person-organization fit. This study suggests direction for establishing an organizational environment for promoting IS-related activities by office workers, so it provides practical implications for organizations with goals related to internal information exposure control.

• Korean Chemical Engineering Research
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• v.52 no.5
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• pp.592-602
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• 2014

In the Integrated Gasification Combined Cycle (IGCC), the stability of the gasifier has strong influences on the rest of the plant as it supplies the feed to the rest of the power generation system. In order to ensure a safe and stable operation of the entrained-flow gasifier and for protection of the gasifier wall from the high internal temperature, the solid slag layer thickness should be regulated tightly but its control is hampered by the lack of on-line measurement for it. In this study, a previously published dynamic simulation model of a Shell-type gasifier is reproduced and two different linear model predictive control strategies are simulated and compared for multivariable control of the entrained-flow gasifier. The first approach is to control a measured secondary variable as a surrogate to the unmeasured slag thickness. The control results of this approach depended strongly on the unmeasured disturbance type. In other words, the slag thickness could not be controlled tightly for a certain type of unmeasured disturbance. The second approach is to estimate the unmeasured slag thickness through the Kalman filter and to use the estimate to predict and control the slag thickness directly. Using the second approach, the slag thickness could be controlled well regardless of the type of unmeasured disturbances.

• Journal of Satellite, Information and Communications
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• v.9 no.3
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• pp.1-4
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• 2014

A radio communication system has interference caused by other radio transmitters operated in co-channel or adjacent channels. Therefore technical specifications are made by considering and investigating the effects of interference between the new system and present systems when the new system will be started to serve in the near future. FTS is used for preventing an abnormal mission and guaranteeing public protection. Recently the next generation FTS's are researched to reinforce the security and to increase the operating capability of simultaneous use. EFTS known as one of the next generation FTS's is suitable for such purposes. In this paper the effects of interference signals on the performance of EFTS are investigated. Noncoherent DPSK and noncoherent CPFSK are considered for the modulation method of EFTS and a FMCW and a pulse RADAR considered as a interferer. The power of FMCW is 20.3dB lower than the power of EFTS and the power of pulse RADAR is 19.1dB lower than that of EFTS. Simulation results show that FMCW interferer reduce $E_b/N_o$ of about 1dB and $E_b/N_o$ of EFTS deteriorates about 0.5dB due to interference signals generated from pulse RADAR.

• Journal of the Society of Disaster Information
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• v.14 no.2
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• pp.130-140
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• 2018

Purpose: In this paper, we propose a design technique for the safety characterization grounding in the construction of the photovoltaic power generation complex which can be useful and useful as an alternative power energy source in our society. In other words, we will introduce the application of safety grounding for each application, which can improve and optimize the reliability of the internal grid from the cell module to the electric room in the photovoltaic power generation complex. Method: We analyze the earth resistivity of the soil in the solar power plant and use the computer program (CDEGS) to analyze the contact voltage and stratospheric voltage causing the electric shock, and propose the calculation and calculation method of the safety ground. In addition, we will discuss the importance of semi-permanent ground electrode selection in consideration of soil environment. Results: We could obtain the maximum and minimum value of ground resistivity for each of the three areas of the data measured by the Wenner 4 - electrode method. The measured data was substituted into the basic equation and calculated with a MATLAB computer program. That is, it can be determined that the thickness of the minimum resistance value is the most favorable soil environment for installing the ground electrode. Conclusion: Through this study, we propose a grounding system design method that can suppress the potential rise on the ground surface in the inner grid of solar power plant according to each case. However, the development of smart devices capable of accumulating big data and a monitoring system capable of real-time monitoring of seismic changes in earth resistances and grounding systems should be further studied.

• Journal of Life Science
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• v.27 no.8
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• pp.945-950
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• 2017

To some extent, the growth of solvent-tolerant Pseudomonas sp. BCNU 106 is limited by toxic solvents. Therefore, various strategies to overcome this limitation need to be investigated. One such strategy is to use exogenous trehalose. The highest intracellular trehalose content of 181.88 mM was measured at 12 hr. The extracellular trehalose content decreased rapidly within 12 to 16 hr in the presence of cyclohexane. Moreover, the number of Pseudomonas sp. BCNU 106 cells grown in Luria-Bertani (LB) broth supplemented with 0.1 M trehalose in the presence of 1%(v/v) cyclohexane, hexane, propylbenzene, and m-xylene increased 89.94-, 89.72-, 91.25-, and 118.9-fold, respectively, in comparison to the control level. High survival rates of 80% and 90% were observed in the presence of cyclohexane and hexane by the addition of 0.05 M trehalose for up to 4 hr, respectively. Exogenously-added trehalose was transported into the cells, and it conferred protection against cyclohexane, hexane, propylbenzene, and m-xylene. Adding exogenous trehalose to the growth medium improved the tolerance of Pseudomonas sp. BCNU 106; thus, it is a potential biocatalyst for biotransformation and biodegradation.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.10
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• pp.3911-3916
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• 2010

In this paper we describe contents and results on running test for ATP on-board equipment, which has propelled as one of the research projects, so called, "Reliability assessment and operation technology development for Korean-type tilting trains" in order to ensure the safety and operation efficiency of tilting trains. We developed tilting trains for the speed-up of conventional lines and for the passenger service improvement where the KTX is not available. And we made progress the operation trial test in the 120,000 km distance with the use of ATS equipment, used in existing lines, for the purpose of the reliability assessment of the developed tilting trains. We decided to accelerate the speed for more than 200km/h with respect to the 6 existing lines including Jungang-line and Chungbuk-line where KTX has not operated. According to this decision, Train control system is to be changed from ATS to ATP. We should have installed an ATP on-board unit in tilting trains and verified the operational suitability, therefore we installed the same ATP on-board unit on tilting trains as that used in the ATP construction project on Gyeongbu-line and Honam-line, and verified that the function and performance of the installed ATP on-board unit conformed to the tilting trains operation.

• Journal of Navigation and Port Research
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• v.43 no.6
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• pp.475-482
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• 2019

The increase in human use and activity in the oceans is leading to marine pollution and habitat destruction. As a result, in particular, marine animals with a long life cycle and small population are threatened with extinction. Thus, the Korean government designated 11 artificial habitats, such as aquariums and marine museums, as Ex-situ conservation institutions to preserve endangered marine life in 2010. However, studies on the significance and economic value of Ex-situ conservation institutions providing marine life conservation services have not been conducted. Thus, the purpose of this study was to estimate the public's quantitative support for the operation policy of Ex-situ conservation institutions, which is a management method for the protection and propagation of marine animals in Korea. To achieve this, the economic value of the marine animal conservation role of the National Maritime Museum was estimated, operated as an Ex-situ conservation institution for the preservation of green turtles in Korea. By using the representative non-market valuation method for public goods known as the contingent valuation method (CVM), the economic value of the Ex-situ conservation institution (National Maritime Museum) was estimated at approximately 41.8 billion won to a maximum of 78.1 billion won. The results of this study can be applied as basic data for marine animal management policymakers in establishing efficient management plans for endangered marine animals in Korea's coastal waters.