• Nuclear Engineering and Technology
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• v.52 no.10
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• pp.2221-2229
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• 2020

After the Fukushima Daiichi nuclear power plant (NPP) accident, level 3 probabilistic safety assessment (PSA) has emerged as an important task in order to assess the risk level of the multi-unit NPPs in a single nuclear site. Accurate calculation of the radionuclide concentrations and exposure doses to the public is required if a nuclear site has multi-unit NPPs and large number of people live near NPPs. So, there has been a great need to develop a new method or procedure for the fast and accurate offsite consequence calculation for the multi-unit NPP accident analysis. Since the multi-unit level 3 PSA is being currently performed assuming that all the NPPs are located at the same position such as a center of mass (COM) or base NPP position, radionuclide concentrations or exposure doses near NPPs can be drastically distorted depending on the locations, multi-unit NPP alignment, and the wind direction. In order to overcome this disadvantage of the COM method, the idea of a new multiple location (ML) method was proposed and implemented into a new tool MURCC (multi-unit radiological consequence calculator). Furthermore, the MURCC code was further improved for the multi-unit level 3 PSA that has the arbitrary number of multi-unit NPPs. The objectives of this study are to (1) qualitatively and quantitatively compare COM and ML methods, and (2) demonstrate the strength and efficiency of the ML method. The strength of the ML method was demonstrated by the applications to the multi-unit long-term station blackout (LTSBO) accidents at the four-unit Vogtle NPPs. Thus, it is strongly recommended that this ML method be employed for the offsite consequence analysis of the multi-unit NPP accidents.

• Journal of the Korea Institute of Building Construction
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• v.17 no.3
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• pp.295-303
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• 2017

Over the past 7 years, the number of victims of construction disasters has been gradually increasing. Compared with projects in other industries, construction projects are highly exposed to safety risks. For this reason, the research methods of predicting and managing the risk of construction disasters are urgently needed that can be applied to a construction site. This study aims to propose a prediction model for a construction disaster using the decision tree technique. The developed the model is reviewed the applicability by evaluating its accuracy based on disaster data. The top three of the prediction values obtained from the proposed model were enumerated, and then the cumulative accuracy were also calculated. The prediction accuracy was 40 percent for the first value, but the cumulative accuracy was 80 percent. Thus, as more disaster data was accumulated, the cumulative accuracy appeared to be higher. If utilized in construction sites, the model proposed in this study would contribute to a reduction in the rate of construction disasters.

• Journal of Applied Biological Chemistry
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• v.59 no.2
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• pp.125-128
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• 2016

The chemical compositions of the essential oil extracted from Albizziae julibrissin barks were analyzed by Gas chromatography-Mass spectrometry spectrometry. Fourteen components were identified, representing 89.23 % of the total oil composition. The analysis of the essential oil revealed that the essential oil contains 14 compounds, accounting for 89.23 % of the total oil. Hexanoic acid was the principal component (41.43 %) of the essential oil, followed by 4,4,6-trimethyl-cyclohex-2-en-1-ol (11.16 %), palmitic acid (9.00 %), 2-pentylfuran (5.66 %), 2-butyl-2-octenal (4.12 %), linoleic acid (3.10%), amyl hexanoate (3.01%), (E,E)-2,4-decadienal (2.49 %), 2-hexylthiophene (2.47 %), caprylic acid (2.13 %), ${\delta}-undecalactone$ (1.52 %), heptanoic acid (1.27 %), 3,5-octadien-2-ol (0.99 %), and 2-octenal (0.88 %). The acaricidal activity of the A. julibrissin oil was tested against Dermatophagoides farina, D. pteronyssinus and Tyrophagus putrescentiae by the fumigant bioassay. Based on the $LD_{50}$ values, the essential oil exhibited strong acaricidal activities against D. farinae ($LD_{50}$, $4.88{\mu}g/cm^3$), D. pteronyssinus ($2.44{\mu}g/cm^3$), and T. putrescentiae ($1.22{\mu}g/cm^3$). These results indicate that A. julibrissin oil could be a source of acaricidal agents for mite control.

• Journal of Applied Biological Chemistry
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• v.59 no.2
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• pp.129-132
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• 2016

This study was conducted to evaluate the attraction effects of Sitophilus zeamais and Tribolium castaneum to light emitting diode (LED) trap in granary and compared with the black light bulb (BLB) trap, which is typical used in commercial trap. The red LED trap showed more attractive to S. zeamais and T. castaneum than that of the BLB. Moreover, the external condition of granary was about 1.5 times more attractive to S. zeamais and T. castaneum than the internal condition of granary. These results suggested that red LED trap could be useful to control S. zeamais and T. castaneum in granary.

• Journal of Information Science Theory and Practice
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• v.7 no.4
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• pp.56-64
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• 2019

Planting intercropping in rubber plantations is another alternative for generating more income for farmers. However, farmers still lack the knowledge of choosing plants. In addition, information for decision making comes from many sources and is knowledge accumulated by the expert. Therefore, this research aims to create a decision support system for growing rubber trees for individual farmers. It aims to get the highest income and the lowest cost by using semantic web technology so that farmers can access knowledge at all times and reduce the risk of growing crops, and also support the decision supporting system (DSS) to be more intelligent. The integrated intercropping ontology and rule are a part of the decision-making process for selecting plants that is suitable for individual rubber plots. A list of suitable plants is important for decision variables in the allocation of planting areas for each type of plant for multiple purposes. This article presents designing and developing the intercropping ontology for DSS which defines a class based on the principle of intercropping in rubber plantations. It is grouped according to the characteristics and condition of the area of the farmer as a concept of the rubber plantation. It consists of the age of rubber tree, spacing between rows of rubber trees, and water sources for use in agriculture and soil group, including slope, drainage, depth of soil, etc. The use of ontology for recommended plants suitable for individual farmers makes a contribution to the knowledge management field. Besides being useful in DSS by offering options with accuracy, it also reduces the complexity of the problem by reducing decision variables and condition variables in the multi-objective optimization model of DSS.

• Korean Journal of Soil Science and Fertilizer
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• v.46 no.2
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• pp.73-80
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• 2013

Due to the fact that possible risk associated with soil-crop-food chain transfer, metal contamination in croplands has become a major topic of wide concern. Accumulation of toxic metals in edible parts of crops grown in contaminated soils has been reported from number of crops including rice, soybean, wheat, maize, and vegetables. Therefore, in order to ensure food safety, measures are needed to be taken in mitigating metal pollution and subsequent uptake by crop plants. Present paper critically reviewed some of the cost effective remediation techniques used in minimizing metal uptake by crops grown in contaminated soils. Liming with different materials such as limestone ($CaCO_3$), burnt lime (CaO), slaked lime [$Ca(OH)_2$], dolomite [$CaMg(CO_3)_2$], and slag ($CaSiO_3$) has been widely used because they could elevate soil pH rendering metals less-bioavailable for plant uptake. Zn fertilization, use of organic amendments, crop rotation and water management are among the other techniques successfully employed in reducing metal uptake by crop plants. However, irrespectively the mitigating measure used, heterogeneous accumulation of metals in different crop species is often reported. The inconsistency might be attributed to the genetic makeup of the crops for selective uptake, their morphological characteristics, position of edible parts on the plants in respect of their distance from roots, crop management practices, the season and to the soil characteristics. However, a sound conclusion in this regard can only be made when more scientific evidence is available on case-specific researches, in particular from long-term field trials which included risks and benefits analysis also for various remediation practices.

• Journal of Korea Society of Industrial Information Systems
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• v.25 no.5
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• pp.31-39
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• 2020

According to lessons learned from an accident of Fukushima Daiichi nuclear power plant, it is advisable to make a comprehensive radiation survey by the accident phase for efficient response and risk management using diverse survey platforms. This study focuses on the technical status of environmental radiation monitoring using a UAV (Unmanned aerial vehicle) and the performance test of developed aerial survey system based on two detectors with an high energy resolution through the field application to contaminated areas. Finally, the performance of aerial survey at diverse flight heights was successfully achieved by introducing the correction factor to represent the results into ambient dose rate at 1m above the ground.

• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.220-220
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• 2015

Water, energy, and food security already became a risk that threatens people around the world. Increasing of resources demand, rapid urbanization, decreasing of natural resources and climate change are four major problems inducing resources' scarcity. Indeed, water, energy, and food are interconnected each other thus cannot be analyzed separately. That is, for simple example, energy needs water as source for hydropower plant, water needs energy for distribution, and food needs water and energy for production, which is defined as W-E-F nexus. Due to their complicated linkage, it needs a computer model to simulate and analyze the nexus. Development of a computer simulation model using system dynamics approach makes this linkage possible to be visualized and quantified. System dynamics can be defined as an approach to learn the feedback connections of all elements in a complex system, which mean, every element's interaction is simulated simultaneously. Present W-E-F nexus models do not calculate and simulate the element's interaction simultaneously. Existing models only calculate the amount of water and energy resources that needed to provide food, water, or energy without any interaction from the product to resources. The new proposed model tries to cope these lacks by adding the interactions, climate change effect, and government policy to optimize the best options to maintain the resources sustainability. On this first phase of development, the model is developed only to learn and analyze the interaction between elements based on scenario of fulfilling the increasing of resources demand, due to population growth. The model is developed using the Vensim, well-known system dynamics model software. The results are amount of total water, energy, and food demand and production for a certain time period and it is evaluated to determine the sustainability of resources.

• Korean Journal of Environmental Agriculture
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• v.40 no.2
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• pp.92-98
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• 2021

BACKGROUND: Unintentional residual pesticide in soil derived from preceding crops and the transfer to succeeding crops was considered a critical barrier for positive list system (PLS). Thus, an uncertain risk is predicted for ethoprophos applied at cultivation of preceding crop (Korean cabbage) to succeeding crop (spinach). METHODS AND RESULTS: Ethoprophos was treated on soil following the recommended dose and 5 times dose according to the safe use guidelines for Korean cabbage after seeding. On the 4 days after harvesting of preceding crop, spinach was sowed. The initial residual amounts of ethoprophos on soil (7.081-19.493 mg/kg) were decreased to 3.832-7.218 mg/kg until the harvest of Korean cabbage, and then finally decreased to 0.011-0.079 mg/kg after spinach cultivation. The uptake rates of ethoprophos from soil by Korean cabbage were 0.01-0.03% and distributed to root (0.150-0.903 mg/kg) and shoot (0.021-0.151 mg/kg), respectively. The residual amounts of uptake and translocation from preceding crop cultivated soil to spinach edible part were found to be below LOQ. CONCLUSION: The plant back internal (PBI) for ethoprophos is not recommended during sequential cultivation of leafy vegetables, since the residual amounts of ethoprophos in spinach were less than MRL (0.02 mg/kg).

• The Journal of the Convergence on Culture Technology
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• v.4 no.4
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• pp.167-171
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• 2018

Alstroemeria (Alstroemeriaceae) is one of the most important cut flowers in international market. But, its characteristics such as low multiplication rates, time consuming process and high risk of carrying viral disease, in vitro propagation techniques based on rhizome meristems culture have been developed. In this study, we conducted this experiment to investigate the effect of hormones and gelling agents on the growth for Alstroemeria in vitro tissue culture. The highest number of shoot and root formation were obtained from the growth medium contains BA 1.0 mg/L and NAA 0.1 mg/L. When 0.25% of gelrite was added up to 50% shoots and roots length were observed compared to other gelling agents. Using these results, it is expected to contribute to the establishment of mass production systems in Alstroemeria.