• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• v.4 no.2
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• pp.111-116
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• 2000

Transboundary air pollution has recently become an area of increasing scientific interest and political concern as countries are receiving air pollutants from their neighbors. In order to gain a better understanding of the long-range transport processes of air pollutants and the source-receptor relationships among neighboring countries, an atmospheric transport model coupled with a RAMS(Regional Atmospheric Modeling System) model was applied to the East Asia region during the entire month of January 1993. The scalar transport option of the RAMS model was used to calculate special atmospheric constituents such as trace gases or aerosols. The sulfate production in clouds and rainwater and its removal processes by dry and wet deposition were considered. The sulfate budget from source regions to receptor regions was estimated by analysing the source-receptor relationships. When a specific receptor site revealed a sulfate value higher than the sulfate concentration based on its own source origin, this was taken to indicate long-range transport from another source region. The contribution ratio from various source region was calculated. The contribution ratio of dry and wet deposition was higher on the main continent of the East region. Furthermore, the high deposition amounts were identified on the west coast of Korea and the East China Sea.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.286-286
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• 2017

We conducted to compare the characteristics of rice flours according to the different milling processes. Five rice varieties (Oryza sativa L.) with different amylose content were prepared by wet and dry milling processes. The moisture contents of wet-milled rice flours (WMR) was mostly three-time higher than those of dry-milled flours (DMR). Water absorption index (WAI), water solubility index (WSI) and swelling power (SP) increased in proportion to temperature ($50-90^{\circ}C$). WAI, WSI, SP of DMR showed higher value than those of WMR. Baeokchal (BOC) which is waxy rice cultivar was significantly high level of WSI. Pasting properties of DMR except BOC cultivar resulted in higher peak viscosity, trough viscosity, final viscosity and Setback. The levels of resistant starch in the four cultivars except Dodamssal (DDS) were under 1% irrespective of Milling processes, whereas the resistant starch contents of DMR and WMR in DDS was 9.18 and 6.27, respectively. Damaged starch content of WMR were less than those of DMR, moreover, negative correlation was observed between amylose content and damaged starch of rice cultivars. These results suggest that the properties of rice flour varied depending on the milling methods and varieties, and it could be a reference for selecting the appropriate processing purposes.

• Journal of the Korean GEO-environmental Society
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• v.11 no.5
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• pp.15-23
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• 2010

Dry sieving, wet sieving and photoscattering analyzer were tested as particle size analyzing methods for sediments from rivers and lakes of Han river, Nakdong river, Youngsan river, and Kumgang river area. Dry sieving showed a big error due to coagulating effect over drying process and this phenomena was severe for lake sediment. Wet sieving and PSA showed an accurate results though wet sieving needs more labor and complicate processes. Freeze-dry or freeze-dry after oxidation of organics with hydrogen peroxide showed improved results but gave lower portion of fine particles in comparing with wet sieving. Heavy metal contents and extractable metal contents were investigated for the sediments and high heavy metal content and extractable amount were obtained from fine particles as expected. Using of proper particle size analyzing method is important and the sediment management should be focused on the fine particles.

• Particle and aerosol research
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• v.5 no.4
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• pp.189-197
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• 2009

Wet-type particulate removal system is employed in most of ironmaking processes. These de-dusting systems require additional downstream aggregates for treatment of water and for drying of the collected slurry. Thus dried slurry can be pressed in shape of briquettes and recycled in the steelmaking process. Different from the wet-type, the dry-type particulate removal systems generate no slurry. A high-temperature, high-pressure de-dusting system with inertial inlet was developed. The target application of this system was to remove particulate matter generated from the novel ironmaking process and other steelmaking processes. In this study we conducted tests with this newly developed system to evaluate the performance of the silica-carbide (SiC) ceramic filters. In addition, for purpose of comparison, we also conducted tests with a unit which has conventional direct inlet. Fe-Particles collected from the novel ironmaking process were used in our tests as test dusts. The temperature and the pressure were kept constant at their respective values $800^{\circ}C$ and $3kg_f/cm^2$.

• Journal of computational fluids engineering
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• v.21 no.2
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• pp.54-61
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• 2016

When spent fuel assemblies from the reactor of nuclear power plants(NPPs) are transported, the assemblies are exposed to short-term operations that can affect the peak cladding temperature of spent fuel assemblies. Therefore, it needs to perform the analysis of heat transfer on spent fuel dry cask during the operation. For 3 dimensional computational fluid dynamnics(CFD) simulation, it is proposed that the short-term operation is divided into three processes: Wet, dry, and vacuum drying condition. The three processes have different heat transfer mode and medium. Metal transportation cask, which is Korea Radioactive Waste Agency(KORAD)'s developing cask, is evaluated by the methods proposed in this work. During working hours, the boiling at wet process does not occur in the cask and the peak cladding temperatures of all processes remain below $400^{\circ}C$. The maximum peak cladding temperature is $173.8^{\circ}C$ at vacuum drying process and the temperature rise of dry, and vacuum drying process occurs steeply.

• Transactions on Electrical and Electronic Materials
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• v.14 no.6
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• pp.304-307
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• 2013

Reverse engineering of semiconductor devices utilizes delayering processes, in order to identify how the interconnection lines are stacked over transistor gates. Cu metal has been used in recent fabrication technologies, and de-processes becomes more difficult with the shrinking device dimensions. In this article, reverse engineering technologies to reveal the Cu interconnection lines and Cu via-plugs embedded in dielectric layers are investigated. Stacked dielectric layers are removed by $CF_4$ plasma etching, then the exposed planar Cu metal lines and via-plugs are selectively delineated by wet chemical solution, instead of the commonly used plasma-based dry etch. As a result, we have been successful in extracting the layouts of multiple layers within a system IC, and this technique can be applicable to other logic IC, analog IC, and CMOS IC, etc.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.24 no.2
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• pp.256-262
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• 2015

This study has an innovative improvement of the ocher tiles production system that aims to resolve social issue of industrial waste and to meet the customer needs for environmental-friendly building materials. By changing a wet type cutting method to a dry type of ocher tiles production system, the three processes such as cleaning, dehydration, and drying can be removed in existing overall process of 17 steps. Accordingly, the application of the wet type cutting method, which is proposed in this study, makes an increase in ocher tiles production from 1,500 to 1,850 pieces per hour. In particular, industrial wastewater that was emerging as the biggest problem in environmental pollutants in the wet cutting method has been removed. In addition, the most serious problems of noise and dust from the operator side, while developing a device for the dry cutting method, are eliminated through the development of additional equipment.

• Journal of the Korean Society of Hazard Mitigation
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• v.3 no.2 s.9
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• pp.89-97
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• 2003

Indirect tensile strength(IDT) test and resilient modulus(Mr) test were performed to evaluate experimental performance characteristics for the conventional and crumb rubber-modified(CRM) asphalt concrete using dry and wet processes asphalt. The IDT test was conducted under three temperatures(5, 10, 20$^{\circ}C$). According to the test results, it was shown that indirect tensile strength of CRM asphalt concrete was lower than that of the conventional one. However, toughness and maximum vortical strain of the CRM asphalt concrete were higher than those of the conventional one. The results of Mr test were presented that Mr of CRM asphalt concrete was higher than that of the conventional one. In addition, it was revealed that the overall laboratory performance characteristics of the wet-processed CRM asphalt concrete was better than those of the dry-processed one.

• Nuclear Engineering and Technology
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• v.55 no.2
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• pp.696-706
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• 2023

Consequences of an anticipated Beyond Design Basis Accident (BDBA) Long-Term Station Blackout (LTSBO) event with complete loss of grid power in the VVER-1200 reactor of Rooppur Nuclear Power Plant (NPP) of Unit-1 are assessed using the RASCAL 4.3 code. This study estimated the released radionuclides, received public radiological dose, and ground surface concentration considering 3 accident scenarios of International Nuclear and Radiological Event Scale (INES) level 7 and two meteorological conditions. Atmospheric transport, dispersion, and deposition processes of released radionuclides are simulated using a straight-line trajectory Gaussian plume model for short distances and a Gaussian puff model for long distances. Total Effective Dose Equivalent (TEDE) to the public within 40 km and radionuclides contribution for three-dose pathways of inhalation, cloudshine, and groundshine owing to airborne releases are evaluated considering with and without passive safety Emergency Core Cooling System (ECCS) in dry (winter) and wet (monsoon) seasons. Source term and their release rates are varied with the functional duration of passive safety ECCS. In three accident scenarios, the TEDE of 10 mSv and above are confined to 8 km and 2 km for the wet and dry seasons, respectively in the downwind direction. The groundshine dose is the most dominating in the wet season while the inhalation dose is in the dry season. Total received doses and surface concentration in the wet season near the plant are higher than those in the dry season due to the deposition effect of rain on the radioactive substances.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09a
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• pp.491-492
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• 2006

The horizontal high energy rotor ball mill ($Simoloyer^{(R)}$) is used to break and activate dry solids. It is used for dry-milling and in the vertical mount for wet-milling in leaching processes. Technical electric arc furnace (EAF) dust with high contents of zinc oxide, zinc ferrite and magnetite is efficiently separated by ambient temperature leaching. The process shows promise for industrial application