• Proceedings of the Korean Institute of Building Construction Conference
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• 2006.05a
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• pp.63-69
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• 2006

In a traditional society, building materials were developed fulfilling the requirements of conveniences and functionalities such as safety, construction work, durability and economical efficiency. However, as the concern about environmental or users' health issues has been elevated recently, research and development about eco-friendly material are alto vigorously promoted further In addition, thanks to the steady growth of domestic industry, the amount of discharged industrial by-product is getting increasing. However, its recycling rate remain at low level as most industrial by-products are filled up in the land, which worsen the environmental pollution. Zeolite powder is cement admixture and is expected to have constraining effect of factors causing symptoms of inhabitants in a new house and alleviates the amount of discharged harmful elements emitted from hardened cement.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.52 no.8
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• pp.359-364
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• 2003

Ageing characteristics of RTV coating materials by corona discharge have been studied. The hydrophobicity recovery of RTV coating materials with 300${\mu}{\textrm}{m}$ thickness was identical with a bulk silicone materials. The RTV coating materials hydrophobicity has been almost lost when its were discharged during 40 seconds by corona discharge of 10㎸, and recovered after about 45 hours. The resistivity of RTV coating materials has not been recovered after 45 hours, though after 80 hours the initiation resistivity value has been recovered up to 95%. There was no critical change of compounds(such as Si and Al) on RTV surfaces by the corona discharge treatment until 100 seconds. In the test of arc erosion, it was seen that the coating sample with silicone rubber as a base material have more longer burn-out time than other samples with FRP or glass base.

• Journal of Radiation Protection and Research
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• v.39 no.1
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• pp.61-64
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• 2014

Radioactive materials are in use and have many applications from the generation of electricity to the purposes of research, industry and medicine such as diagnosis and therapy. In the course of their use some of radioactive substances may be discharged into the environment from facilities using the unsealed radioactive materials, which are main artificial sources occurring the public exposure. Discharges are in the form of gases, particles or liquids. This paper provides procedures to estimate the level of the public exposure based on the conservative assumptions and simple calculations in the facility using unsealed liquid sources. They consist of two processes; (1) to calculate maximum concentration of gaseous effluents discharged through the exhaust pipe and average concentration of liquid effluents discharged through the drain of the storage tank, (2) to compare each of them to numerical guidances for the discharges of radioactive gaseous and liquid effluents mentioned in the related notification. For this purpose followings are assumed properly; daily usage, form and dispersion rate of radionuclides, daily amount of radioactive liquid waste and exhaust and drainage equipment. The procedures are readily applicable to evaluate environmental effects by planned effluent discharges from facilities using the unsealed radioactive materials. In addition they may be utilized to obtain practical requirements for radiation safety control necessary for the reductions of the public exposure.

• Journal of Environmental Impact Assessment
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• v.24 no.6
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• pp.549-560
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• 2015

The priorities of siting restriction was derived from quantification of environmental hazard according to industrial classification based on 'Chemical Ranking and Scoring System(CRS)' which is handling the discharge characteristics of 31 industrial classifications regulated from locating at 'Industrial Complex in Rural Area(ICRA)'. CRS that is utilizing the data of 'Pollutant Release and Transfer Registers(PRTR)' is applied to determine human health risk and ecological risk which are calculated by discharged amount and materials $LC_{50}$ according to water, soil and air media based on industrial classification. From this process, exposure assessment and toxicity assessment for integrating the adverse environmental impact and the mitigation effect of environmental risk according to the development of environmental technologies into establishing the rational landuse management method for the 31 industrial classifications regulated from locating at ICRA was analyzed. From the assessment result of the siting restriction removal at ICRA for 31 industrial classifications, based on 2012 year reference 6 industries that includes Manufacture of Guilt Coloration Surface Processing Steel Materials, Manufacture of Biological Product, Manufacture of Smelting Refining and Alloys of Copper, Dyeing and Finishing of Fibers and Yarns, Manufacture of Other Basic Iron and Steel n.e.c., Rolling Drawing and Extruding of Non-ferrous Metals n.e.c. are calculated as having relatively lower environmental hazards, thus it is judged that the siting restriction mitigation at ICRA is possible for the 6 industrial classifications that are not discharging the specific hazardous water contaminants during manufacturing process.

• Clean Technology
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• v.3 no.2
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• pp.13-24
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• 1997

The present paper aims to give basic information to establish zero emission material cycle including the minimization of emissions from industrial production processes and the area in regional scale. Strategies and methodologies to analyze emissions from the production processes and our human activities and to reduce those emissions by refining and/or replacing the unit process with the alternatives are introduced as well. Quantitative evaluation and management systems of any raw materials and the production process are from vie points of treatment are essential. Estabiishment of a process networking for the recycle of discharged non-products materials by the intra-process, trans-process and the trans-industries are proposed. Procedures and priorities to formulate industrial and regional zero emission system are proposed as well.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.06a
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• pp.397-398
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• 2009

In oder to investigate of partial discharge of nano-composites materials, we have studied partial discharge appling voltage from 5 to 30 [kV] to make an artificial defect with the epoxy adding to 0, 0.4, 0.8, and 1.6 [wt%], respectively. The experimental result, we have found that $SiO_2$ of 0.4 (wt%] was superior to others also, it is found that the effect of isolate diagnosis to get the slope for the discharged electric charge distribution.

• Bulletin of the Korean Chemical Society
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• v.31 no.9
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• pp.2479-2482
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• 2010

Using a pinhole-type glass nozzle equipped for a corona-excited supersonic expansion (CESE), precursor 2,6-dichlorotoluene seeded in a large amount of inert carrier gas helium was discharged to produce jet-cooled but electronically excited benzyl-type radicals. The visible vibronic emission spectrum was recorded with a long-path monochromator to observe vibronic bands in the $D_1{\rightarrow}D_0$ electronic transition of benzyl-type radicals. The spectral analysis revealed the generation of not only the 2,6-dichlorobenzyl radical as a typical product, but also the o-chlorobenzyl radical as an unexpected species, which indicates the possible molecular rearrangement in eliminating a chlorine atom from the benzene ring. A possible mechanism is proposed for the formation of the o-chlorobenzyl radical from the precurs or in the gas phase.

• Journal of the Semiconductor & Display Technology
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• v.20 no.2
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• pp.87-91
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• 2021

Various Cu ions are discharged into water from various industries, which results in a severe trouble for groundwater, soil, air, and eventually animals and humans. In this work, graphene oxide (GO) is introduced as a Cu removal absorber and the real-time monitoring method is demonstrated. The results show that GO is a very effective material to absorb Cu ions in the solution. In addition, the residual Cu ions in the solution is monitored via optical transmittance method, which well match with Inductively Coupled Plasma Mass Spectrometer (ICP-MS) analysis.

• Restorative Dentistry and Endodontics
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• v.47 no.4
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• pp.45.1-45.10
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• 2022

Objectives: This study evaluated the relationship between the battery charge level and irradiance of light-emitting diode (LED) light-curing units (LCUs) and how these variables influence the Vickers hardness number (VHN) of a bulk-fill resin. Materials and Methods: Four LCUs were evaluated: Radii Plus (SDI), Radii-cal (SDI), Elipar Deep Cure (Filtek Bulk Fill, 3M Oral Care), and Poly Wireless (Kavo Kerr). Irradiance was measured using a radiometer every ten 20-second activations until the battery was discharged. Disks (4 mm thick) of a bulk-fill resin (Filtek Bulk Fill, 3M Oral Care) were prepared, and the VHN was determined on the top and bottom surfaces when light-cured with the LCUs with battery levels at 100%, 50% and 10%. Data were analyzed by 2-way analysis of variance, the Tukey's test, and Pearson correlations (α = 5%). Results: Elipar Deep Cure and Poly Wireless showed significant differences between the irradiance when the battery was fully charged versus discharged (10% battery level). Significant differences in irradiance were detected among all LCUs, within each battery condition tested. Hardness ratios below 80% were obtained for Radii-cal (10% battery level) and for Poly Wireless (50% and 10% battery levels). The battery level showed moderate and strong, but non-significant, positive correlations with the VHN and irradiance. Conclusions: Although the irradiance was different among LCUs, it decreased in half of the devices along with a reduction in battery level. In addition, the composite resin effectiveness of curing, measured by the hardness ratio, was reduced when the LCUs' battery was discharged.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 1999.10c
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• pp.739-746
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• 1999

Discharge characteristics of organic materials and nutrients were estimated in the catchment area of relaimed area-Saemankeum-. Discharge load of BOD5 was high in the domestic system, while nitrogen and phosphorous were discharged mainly from the livestock system and the land . Load was so dependent on the precipitation that it increased in the rainy season, particulary in nitrogen and phosphorus. Loads from nonpoint sources in this area were higher compared with others.