• Nuclear Engineering and Technology
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• v.50 no.8
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• pp.1355-1363
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• 2018

Many radionuclides exist in normal environment and artificial radionuclides also can be detected. The radionuclides ($^{131}I$) are widely used for labeling compounds and radiation therapy. In Korea, the radionuclide ($^{131}I$) is produced at the Radioisotope Production Facility (RIPF) at the Korea Atomic Energy Research Institute in Daejeon. The residents around the RIPF assume that $^{131}I$ detected in environmental samples is produced from RIPF. To ensure the safety of the residents, the radioactive concentration of $^{131}I$ near the RIPF was investigated by monitoring environmental samples along the Gap River. The selected geographical places are near the nuclear installation, another possible location for $^{131}I$ detection, and downstream of the Gap River. The first selected places are the "front gate of KAERI", and the "Donghwa bridge". The second selected place is the sewage treatment plant. Therefore, the Wonchon bridge is selected for the upstream of the plant and the sewage treatment plant is selected for the downstream of the plant. The last selected places are the downstream where the two paths converged, which is Yongshin bridge (in front of the cogeneration plant). In these places, environmental samples, including sediment, fish, surface water, and aquatic plants, were collected. In this study, the radioactive iodine ($^{131}I$) detection along the Gap River will be investigated.

• Journal of Nutrition and Health
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• v.43 no.1
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• pp.5-11
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• 2010

We conducted comparative study on metabolizable energy content of extracts of angelica keiskei and its byproduct. Total six different groups consisting of five test groups treated with angelica keiskei and one control group were compared. Each of the five test groups were given 30% of one of whole plant, extracts, fermented of extracts, byproduct and extracts plus byproduct, respectively, mixed with AIN93M. After 3 days of adjustment period, all groups were subjected to 4 days of test period during which the amounts of feed intake and excretion were measured everyday. All feces were treated for the prevention of decomposition and changes before its energy content were measured using a bomb calorimeter. The amount of excretion was $4.8\;{\pm}\;0.3\;g$/rat/3 days in control group and 9.9-15.0 g/rat/3 days in the groups were added with extracts of angelica keiskei indicating that the angelica keiskei-treated groups produce 2-3 times more excretion. Metabolic energy of control diet was 4,133.3 kcal. This was found to be 15 to 20% higher compared with the metabolic energy content ranging from 3,117.0 kcal/kg (extracts of angelica keiskei) to 3,259.8 kcal/kg (extracts plus byproducts) angelica keiskei-treated groups. This is interpreted as the result of the decreased metabolic energy in the test diets were substituted with 30% of ngelica keiskei-treated ingredient which has low metabolic content itself. One notable finding is that the metabolic content of the group mixed with byproducts and extracts (1,763.0 kcal/kg) is 27% higher than that of extracts of angelica keiskei (1,286.8 kcal/kg) indicating that mechanical grinding increases the rate of digestion and absorption increasing, in turn, the energy content used in the body. The results of analysis of overall caloric absorption showed absorption rate in order of Whole plant < extracts < byproduct < extract plus byproduct < fermented of extract.

• Journal of Energy Engineering
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• v.28 no.3
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• pp.18-25
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• 2019

In this study, in order to solve the problem of the program of calculating code input by experienced users in the power generation, the wide area energy network research group developed the local heating operation analysis program EntPLAN, which can be easily used by anyone, including scalability, with domestic technology. Therefore, the Commission intended to compare the heat sources, heat demand, and the results of operation of the combined heat plant (CHP) on the energy network through simulation with the EnetPLAN and the program A on the market. The results showed that the heat and power output on the energy network of the EnetPLAN and A programs were mostly similar in pattern in the simulation results of the heat supply and the operation method of the accumulator. This enabled the application of the simulation for the various operation modes of the cogeneration facilities existing on the energy network. It is expected that EntPLAN, which was developed with domestic technology, will be easily applied in the field in the future and will present efficient operation simulation results.

• Journal of Energy Engineering
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• v.28 no.1
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• pp.22-29
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• 2019

A heat pump system using wasted heat from thermal effluent to supply the heating energy can reduce energy consumption and emissions of greenhouse gases by greenhouse facilities nearby. The Jeju National University consortium constructed a heat pump system using the thermal effluent from the Jeju thermal power plant of KOMIPO to provide with cool or hot water to greenhouse facilities located 3 km from the power station. In this paper, the system configuration of the heat pump system was summarized, and the results of operations for demonstration of a heating performance carried out during the winter season in 2018 were investigated. The preoperational tests proved that the water temperature drop through the pipeline transporting extracted heat was less than $2^{\circ}C$. The COP (coefficient of performance) of the heat pump was higher than 4.0, and hot water with the maximum temperature of $50^{\circ}C$ could be supplied to greenhouse facilities by utilizing wasted heat from thermal effluent.

• Environmental Engineering Research
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• v.12 no.5
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• pp.197-200
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• 2007

Advanced control is getting increasingly demanded in water and wastewater treatment systems. Various case studies have shown significant savings in operating costs, including energy costs, and remarkably short payback times. It has been demonstrated that instrumentation, control and automation (ICA) may increase the capacity of biological nutrient removing wastewater treatment plants by 10-30% today. With further understanding and exploitation of the mechanisms involved in biological nutrient removal the improvements due to ICA may reach another 20-50% of the total system investments within the next 10-20 years. Disturbances are the reason for control of any system. In a wastewater treatment system they are mostly related to the load variations, but many disturbances are created also within the plant. In water supply systems some of the major disturbances are related the customer demand as well as to leakages or bursts in the pipelines or the distribution networks. Hardly any system operates in steady state but is more or less in a transient state all the time. Water and energy are closely related. The role of energy in water and wastewater operations is discussed. With increasing energy costs and the threatening climate changes this issue will grow in importance.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.1571-1574
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• 2003

A shared compliant control scheme based on IMC is proposed for the position-force force reflecting control system. The controller of the slave manipulator is designed by IMC method for the open loop unstable plant. The compliant control is implemented by first order low pass filter. In the proposed scheme, the slave manipulator well tracks the position of the master manipulator in free space and the compliance of the slave manipulator is autonomously controlled in contact condition. The simulation results show that the excellence of the proposed controller.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.29 no.1
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• pp.70-79
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• 2015

In this paper, enhanced stand-alone operation and development of Matlab/Simulink model of emergency diesel based hybrid energy system is presented. Simulations based on the remote community or islands were performed for PV-diesel-battery hybrid system. Modeling of PV-diesel-battery integrated system is done to perform under the solar radiation and load conditions on Matlab/Simulink platform. The models of diesel generator unit, battery energy storage system, PV and frequency-power control are developed and simulation studies have been carried out under various conditions using Matlab/Simulink and SimPowerSystem. It is demonstrated that the proposed system can provide reliable and good quality power to the customers in diesel synchronous generator-based hybrid energy systems.

• Journal of Environmental Science International
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• v.12 no.6
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• pp.643-650
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• 2003

We analyzed the amount of environmental loads, and the amount of energy consumption through life cycle assessment from a discharge stage to the ultimate disposal to municipal solid waste in Seoul. We carried out inventory analysis of the amount of environmental loads that made the object range collection, intermediate treatment, and the final treatment, and took into consideration each stage exceptions CO$_2$ and NOx , the amount of SOx discharge, and energy consumption. We applied the data of an object model, and acquisition processed the scale of an object model suitably and applied to it to difficult data using the data of the Yokohama City incineration plant in Japan. The amount of environmental loads per Iton of municipal waste were analyzed CO$_2$ 0.4C-ton, SOx 0.4kg and NOx 0.8kg. Moreover, the amount of energy consumption which is 2.4Gcal was computed.

• Journal of Radiation Protection and Research
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• v.28 no.3
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• pp.239-245
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• 2003

Every nuclear power plant measured concentrations of tritium in groundwater and surface water around the plants periodically. It was not easy to predict the tritium concentration only with these measurement data in case of various release scenarios. KAERI developed a new approach to find the relationship between the tritium release rate and tritium concentration in the environment. The approach was based upon a dynamic compartment model. In this paper the dynamic compartment model was modified to predict the tritium behavior more accurately. The mechanisms considered for the transfer of tritium between the compartments were evaporation, groundwater flow, infiltration, runoff, and hydrodynamic dispersion. Time dependent source terms of the compartment model were introduced to refine the release scenarios. Also, transfer coefficients between the compartments were obtained using realistic geographical data. In order to illustrate the model various release scenarios were developed, and the change of tritium concentration in groundwater and surface water around the nuclear power plants was estimated.

• Proceedings of the Korean Nuclear Society Conference
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• 1997.05a
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• pp.611-616
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• 1997

The Level 1 probabilistic safety assessment(PSA) for Wolsong(WS) 2/3/4 nuclear power plant(NPPs) in design stage is performed using the methodologies being equivalent to PWR PSA. Accident sequence evaluation program(ASEP) human reliability analysis(HRA) procedure and technique for human error rate prediction(THERP) are used in HRA of WS 2/3/4 NPPs PSA. The purpose of this paper is to introduce the procedure and methodology of HRA in WS 2/3/4 NPPs PSA. Also, this paper describes the interim results of importance analysis for human actions modeled in WS 2/3/4 PSA and the findings and recommendations of administrative control of secondary control area from the view of human factors.