• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2021.10a
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• pp.277-280
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• 2021

Recently as various contents are mass produced based on high accessibility, the media contents market is more active. Users want to find content that suits their taste, and each platform is competing for personalized recommendations for content. For an efficient recommendation system, high-quality metadata is required. Existing platforms take a method in which the user directly inputs the metadata of an image. This will waste time and money processing large amounts of data. In this paper, for media hyperpersonalization recommendation, keyframes are extracted based on the YCrCb color model of the video based on movie trailers, movie genres are distinguished through supervised learning of artificial intelligence and In the future, we would like to propose a utilization plan for generating metadata.

• Journal of Energy Engineering
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• v.23 no.3
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• pp.125-131
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• 2014

In order to increase landfill gas (LFG) production with food waste leachate, this study was confirmed to be acidogenetic conditions for landfill site injection. Thereby, it was conducted for acidogenetic treatments to determine the decrease in viscosity and VFA production. After acidogenesis treatments, solubility of food waste leachate increased approximately 15%, and as a result, UASB and CSTR were similar by reactor type using the change of retention time. Based on the result of the change in viscosity by reactor type, efficiency of UASB showed approximately 11.38% of higher decrease in viscosity as $76.95{\pm}3.27%$ vs. CSTR. Also, VFA production showed the higher increase of 2.01 times (UASB) and 1.76 times (CSTR) respectively at the point of increasing retention time from 3 to 5 days. From the above results, efficiency of UASB in a reactor was relatively higher because large molecular lead to longer retention time than small molecular due to having screen effect in the fixed media.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.4 no.1
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• pp.9-15
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• 2006

For the accurate safety assessment of potential radioactive waste disposal site which is located in the crystalline rock it is important to simulate the mass transportation through engineered and natural barrier system precisely, characterized by porous and fractured media respectively. In this work the methods to construct discrete fracture network for the analysis of flow and mass transport through fractured-porous medium are described. The probability density function is adopted in generating fracture properties for the realistic representation of real fractured rock. In order to investigate the intersection between a porous and a fractured medium described by a 2 dimensional rectangular and a cuboid grid respectively, an additional imaginary fracture is adopted at the face of a porous medium intersected by a fracture. In order to construct large scale flow paths an effective method to find interconnected fractures and algorithms of swift detecting connectivities between fractures or porous medium and fractures are proposed. These methods are expected to contribute to the development of numerical program for the simulation of radioactive nuclide transport through fractured-porous medium from radioactive waste disposal site.

• Economic and Environmental Geology
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• v.29 no.1
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• pp.45-55
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• 1996

Although the Dongjin Au-Ag-Cu mine had been abandoned since about forty years ago, the results of this study on the dispersion patterns and contamination level of heavy metals in the hydrologic system flowing via the waste rump show that the environmental impacts from the mine wastes are still significant. The stream water in the vicinity of the waste rump is severely acidified (pH 3.8 to 4.4) and highly enriched in various dissolved heavy metals. The heavy metal contents of the stream water and stream sediments are systematically attenuated with increasing distance from the mine area. However, it is worth to note that continuous attenuation of heavy metal contents in both media were reenriched in downstream area more than 800 m apart from the mine because it can be acted as a secondary source of heavy metal pollution. The heavy metals, especially Cd, Cu and Zn of polluted downstream sediments mainly occur in Fe-Mn oxides and organic materials, which indicates that these elements are the main pollutants from the waste rump of the Dongjin mine. The heavy metal contents of crops, such as sesame, perilla, red Pepper and brown rice, collected from the polluted farm land in the downstream area are lower than those of land plants from stream sides, but significantly higher in Cd, Cr, Cu and Zn than those from the unpolluted farm land. Especially, almost all of the crops in polluted farm land have been severly contaminated by Cd (>0.4 ppm). On the other hand, the heavy metal contents of the crops collected from refreshed farm land by means of a soil addition method shows significantly lowered level comparing with those of polluted area, which indicates that a soil addition method was effective for the refreshment of polluted farm land by toxic metallic pollutants. Wormwoods from this area showed very high contents in a11 the heavy metals even in unpolluted area (Cd > 1 ppm, Cr > 1 ppm, Cu > 11 ppm, Pb> 4 ppm, Zn > 55 ppm), indicating that a special caution must be payed when one takes ingest them.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.2 no.3
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• pp.201-209
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• 2004

Important operation parameters and performance of a high temperature ceramic candle filter system were evaluated through a series of demonstration tests at a pilot-scale vitrification plant. At the initial period of each test, due to the growth of dust cake on the surface of ceramic candles, the pressure drop across the filter media increased sharply. After that it became stable to a certain range and varied continuously proportion to the face velocity of off-gas. On the contrary, at the initial period of each test, the permeability of filter element decreased rapidly and then it became stable. Back flushing of the filter system was effective under the back flushing air pressure range of 3∼5 bar. Based on the dust concentrations measured by iso-kinetic dust sampling at the inlet and outlet point of HTF, the dust collection efficiency of HTF evaluated. The result met the designed performance value of 99.9%. During the demonstration tests including a hundred hour long test, no specific failure or problem affecting the performance of HTF system were observed.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2003.11a
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• pp.101-104
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• 2003

In this study based on the mass transfer theory, experiments for the evaporation rates depending on various conditions were carried out through the operation of the existing Natural Evaporation Facility in KAERI. Evaporation media were made of the cotton and polyester. Air circulation in the facility was forced by exhausting fans. The evaporation rate and the decontamination factor were calculated by the result of experiment. The evaporation rate increased as the flow rate of air supply, the feed rate of liquid waste, and the temperature of supplied air increased. As for the humidity of supplied air, the evaporation rate was getting higher as the humidity was getting lower. As the result of this study, operation conditions of the Natural Evaporation Facility are optimized as follows : The air temperature above $8^{\circ}C$, the air humidity below 70%, the air flow rate 1.14-1.47 m/sec, and the liquid waste feed rate $4.6{\ell}/hr\cdotm^2$. The decontamination factor and the radioactivity are $5.1{\times}10^3$and $4.7{\times}10^{-13}{\mu}Ci/\textrm{m}{\ell}$ respectively, at the above mentioned optimum operation conditions. The air factor in the Dalton's equation for evaporation was determined from results of experiment on the temperature, the humidity, and the flow rate of supplied air as following : $[\textit{Eh}=(0.018 + 0.0141\textitv) {\delta}textitH]$

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1994.10a
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• pp.201-208
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• 1994

To secure long-term structural safety of underground openings for radioactive waste disposal, the proper structural safety analyses are required. Especially, the structural analysis for underground openings should consider the effects of groundwater pressure. The objective of this study is to develop the structural analysis method for saturated rock masses. In this study, the interaction between groundwater distribution and structural behavior of rock masses are carried out to develop the structural analysis method of saturated rock masses. Then, a 3-Dimensional Multi-Phase Dynamic Analysis Program (MPDAP-3D) has been developed by modifying the existing MPDAP which is based on the concept of 2-dimensional two-phase media.

• Journal of the Korean Ceramic Society
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• v.19 no.2
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• pp.145-151
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• 1982

Many materials such as silica gel, metallic oxide, activated alumina and alkaline earth metal carbonates were employed as filter media for gaseous oxides of ruthenium volatilized during high level radioactive waste processing. The adsorption efficiency of ruthenium on these materials was evaluated. For the purpose of observing behavior of ruthenium oxides, thermogravimetric analysis of ruthenium oxide in a stream of oxygen was carried out. The rate of volatilization was proportional to the square root of oxygen partial pressure, and increased exponentially with temperature. At $650^{\circ}C$, gaseous ruthenium oxides showed a strongly marked effect of deposition. Of all the materials available, calcium oxide proved to be the best that could be used to adsorb ruthenium.

• 한국신재생에너지학회:학술대회논문집
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• 2008.05a
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• pp.626-629
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• 2008

In this study, a geothermal power generation system using the Kalina cycle was investigated by the simulation method. The Kalina cycle system can be used for the utilization of a low-temperature heat sources such as geothermal and industrial waste heat that are not hot enough to produce steam. The sea/river water can be considered as a cooling media. A steady-state simulation model was developed to analyze and optimize its performance. The model contains a turbine, a pump, an expansion valve and heat exchangers. The turbine and pump were modelled by an isentropic efficiency, while a condenser, an evaporator and a regenerative heat exchanger were modeled by UA-LMTD method with a counter-flow assumption. The effect of the ammonia fraction at the separator inlet on the cycle performance is investigated in detail.

• Journal of Wetlands Research
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• v.2 no.1
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• pp.59-67
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• 2000

The aim of this study is to identify the role of this natural treatment system, which consists of Oenanthe javanica and wasted concrete as bio-media. Therefore, it was designed to experiment water quality, BOD, SS, T-N, T-P to recognize the efficiency of treatment system with one biofilter tank using wasted concrete and vegetation bed using Oenanthe javanica. It was also designed to compare two different biofilter reactors, which are air lift and upflow methods. In the result, it was demonstrated that upflow method is more efficient system to control water quality of polluted streams. The vegetation bed using Oenanthe javanica has the treatment efficiency of 41 % (BOD), 52 % (COD), 60% (SS), 36 % (T-P), 70 % ($NH_4-N$). It was therefore proved that removal rates of nutrients are not so good except $NH_4-N$ concentration with nitrification.