• Proceedings of the Korean Institute of Building Construction Conference
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• 2018.11a
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• pp.31-32
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• 2018

Lately, cement mixed siliceous powder waterproofing coating has been used as a waterproofing material in the wet environment condition of an underground concrete structure. Underground is exposed to environmental influences such as pressure of ground water, pressure of soil. However, the quality standard for pressure (water pressure, earth pressure) is not specified in the specification of the cement mixed siliceous powder waterproofing coating. Therefore, in this study, the permeability test was carried out based on the assumption that the durability should be verified in consideration of the environmental aspects of the material in actual field. As a result of the test, the permeability was generated from the inorganic single type material, but it was caused by the sealing failure and the test error, and the permeability was not generated in most of the materials. The results of this study will be analyzed by reviewing the physical properties of the material, and the research direction will be resumed.

• Environmental Engineering Research
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• v.15 no.1
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• pp.35-40
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• 2010

Bung Boraphet is the largest freshwater reservoir in Thailand. This study examined the accumulation of copper (Cu) and lead (Pb) in water, sediment and tissues of Asian clams (Corbicula sp.) within Bung Boraphet to assess the possible polluting effect of soil erosion and the dissolution of water soluble salts from the Nan River. Samples were collected from 12 study sites within Bung Boraphet between February and December 2008. The physicochemical parameters of the water including temperature, pH, turbidity, ammonia nitrogen, nitrate nitrogen, orthophosphates, biochemical oxygen demand, dissolved oxygen, Cu, and Pb were measured. The water in Bung Boraphet was found to be medium clean according to the surface water quality standard of Thailand. The levels of Cu and Pb in the water were low but heavy metals were detected at higher levels in the sediment and tissues of Corbicula sp. In the near future, management practices and regulator approaches for Cu and Pb contamination will be needed to protect the water in Bung Boraphet.

• Journal of the Korean Society of Groundwater Environment
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• v.6 no.1
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• pp.8-13
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• 1999

This research was investigated to examine the status of goundwater contamination in Chung-Nam area over 2 years from 1996 May to 1998 May. The results show that the overall detection rates of VOCs (volatile organic compounds) by region were as followed: industrial region > agricultural & industrial complex region > gas station region > around industrial region > downtown region, and excess rates of those were as followed: industrial region > gas station region > agricultural & industrial region > around industrial region > downtown region. Benzene and TCE of VOCs examined in Chon-An industrial region exceeded drinking water standard. At the agricultural & industrial complex region, the observed mean concentration of TCE was 3.107 mg/L and TCE was also detected at 48.152 mg/L which is 100 times higher than drinking water standard, and other VOCs were also observed at higher concentrations as well. Based on our studies, It is concluded that appropriate remedial action should be performed to protect further groundwater contamination and to restore groundwater quality in Chung-Nam area.

• Journal of Korean Society for Atmospheric Environment
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• v.16 no.5
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• pp.453-467
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• 2000

The aim of this research is to collect and characterize fine particles (FPM:$\leq$2.5${\mu}{\textrm}{m}$) and coarse particles (CPM: 2.5~10${\mu}{\textrm}{m}$) using a low volume air sampler provided by the IAEA, at urban (Taejon) and rural area(Wonju) for a period of about two years(April 1996 to May 1998) and to promote a use of nuclear analytical techniques for air pollution studies. For the collection of airborne particulate matter (PM(sub)10), the Gent stacked filter unit sampler and polycarbonate membrane filters were employed. The concentration of trace elements in collected APM samples were determined byu instrumental Neutron Activation Analysis. For validation of the analytical data, internal quality control were implemented by using both the comparison of the analytical results of standard reference materials(NIST SRM 1648) and interlaboratory comparison for proficiency test (NAT-3). The standard uncertainty was less than 15% and Z-score of two samples were within $\pm$1. The monitoring of (PM(sub)10) mass concentration and elemental concentrations were carried out weekly. The average mass concentration of (PM(sub)10) in urban and rural areas were 59.2$\pm$36.5$\mu\textrm{g}$/㎥ and 41.4$\pm$23.7$\mu\textrm{g}$/㎥, respectively. To investigate the emission source, the enrichment factors were calculated for the fine and coarse particle fractions at two sites, respectively and these values were classified for anthropogenic and soil origin elements.

• Journal of the Korean Society for Marine Environment & Energy
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• v.13 no.4
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• pp.249-262
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• 2010

Regulatory test method for Total Petroleum Hydrocarbons (TPHs) in the marine sediment and biota has not still been established even though TPHs are one of the major pollutants in marine environment. Based on the Korean Soil Standard Method (SSM) for TPHs, we considered a new treatment method for determining TPHs in marine environmental samples by using a Gas chromatography coupled with Mass spectrometric detector. We suggested an improved recovery test for quality control procedures and introduced analytical procedures of removing sulfur, polar organic materials, water and saponification for removing neutral lipids in marine bottom sediments and biota.

• Journal of the Korean Geosynthetics Society
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• v.11 no.1
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• pp.57-63
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• 2012

Steel slag has the nature to hydrate and expand when in contact with non-reacting CaO and water, and thus can be used only in limited scope for landfill disposal as well as for recycling as civil construction aggregates. In order to use such steel slags more efficiently, the applicability of steel slag as sand mat alternative material was reviewed. In general, sand mat is used in soft ground surface reinforcement method and horizontal drain method, and is installed simultaneously with soft ground vertical drain method. Therefore in this study steel slag designing method and application standard etc were examined to recycle steel slag as sand mat alternative material, and laboratory soil test and model test were done. Test results indicated that the designing method and application standard meet various environment and quality standards, meaning that steel slag can be utilized as sand mat alternative material, and analysis of slag mat bearing capacity also indicated that use of steel slag produces double or more bearing capacity compared with existing sand mat.

• FLOWER RESEARCH JOURNAL
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• v.17 no.4
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• pp.332-335
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• 2009

A new cultivar of Rosa hybrida 'Loving Heart' was developed by crossing Gyeongkyo R-6 and 'Noblesse' at Gumi Floricultural Experiment Station in 2002. Characteristics trials were conducted three times from 2004 to 2007. This cultivar showed dark pink flower color (RHS, Red-purple group 66-B) and standard type with good flower shape. The flower diameter is 10.3cm and the number of petals per flower is 55. Vase life of 'Loving Heart' could be as long as 12.3days. The yield of 'Loving Heart' was $127stems/m^2/year$. 'Loving Heart' has good quality of cut flower and strong vigor in plant growth. This cultivar has straight stems and is easy to culture because of a few prickles on the top of stem. This cultivar is appropriate for both soil and solution(hydroponics) cultures.

• FLOWER RESEARCH JOURNAL
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• v.16 no.3
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• pp.218-221
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• 2008

A new cultivar of Rosa hybrida 'Wooami Salmon' was developed by crossing 'Silver 87' and 'Lambada' at Gumi Floricultural Experiment Station in 2001. Characteristics trials were conducted three times from 2003 to 2006. This cultivar showed pale salmon flower color (RHS, Orange group 27-B) and standard type with good flower shape. The flower diameter is 10.8cm and the number of petals per flower is 46. Vase life of 'Wooami Salmon' could be as long as 12.8 days. The yearly mean yields of 'Wooami Salmon' was $129stems/m^2$. 'Wooami Salmon' has good quality of cut flower and strong vigor in plant growth. This cultivar is appropriate for both soil and solution(hydroponics) cultures.

• Journal of the Korea Society of Computer and Information
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• v.25 no.12
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• pp.299-303
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• 2020

Currently, electric furnace oxide slag is mostly used for soil or road use due to its nature. Although electric furnace oxidation slag is an industrial byproduct, not a circulating aggregate, the shortcomings of electric furnace oxidation slag are gradually being resolved due to the development of technology, and it is said that electric furnace oxidation slag is enough to be used as aggregates in light of research and technology conditions outside of Korea. However, there are difficulties in expanding construction and application, given that the current standard for electric furnace oxid slag only defines recycling purposes and does not have specific regulations. Therefore, institutional supplementation is needed to utilize oxidation slag as electricity. In this study, the laws and system related to oxidation slag by electricity are reviewed, laws related to recycled aggregate are examined, and measures for improvement are proposed.

• Journal of the Korean Geotechnical Society
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• v.38 no.5
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• pp.5-17
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• 2022

A pile is a type of medium for constructing superstructures in weak geotechnical conditions. A pretensioned spun high-strength concrete (PHC) pile is composed of high-strength concrete with a specified strength greater than 80 MPa. Therefore, it has advantages in resistance to axial and bending moments and quality control and management since it is manufactured in a factory. However, the skin friction of a pile, which accounts for a large portion of the pile bearing capacity, is only approximated using empirical equations or standard penetration test (SPT) N-values. Particularly, there are some poor research results on the pile-soil interface under the seismic loads in Korea. Additionally, some studies do not consider geoenvironmental elements, such as groundwater pH values. This study performs sets of cyclic simple shear tests using submerged concrete specimens for 1 month to consider pH values of groundwater and clay specimens composed of kaolinite to generate a pile-soil interface. 0.2 and 0.4 MPa of normal stress conditions are considered in the case of pH values. The disturbed state concept is employed to express the dynamic behavior of the interface, and the disturbed function parameters are newly suggested. Consequently, the largest disturbance increase under basic conditions is observed, and an early approach to the failure under low normal stress conditions is presented. The disturbance function parameters are also suggested to express this disposition quantitatively.