• Title/Summary/Keyword: domestic soil

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Pine Forest Soil Characteristics and Major Soil Impact Factors for Natural Regeneration

  • Kim, Min-Suk;Kim, Yong-Suk;Min, Hyun-Gi;Kim, Jeong-Gyu;Koo, Namin
    • Korean Journal of Soil Science and Fertilizer
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    • v.50 no.3
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    • pp.179-186
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    • 2017
  • This study was conducted to identify characteristics of domestic pine forest soils and to elucidate major soil influencing factors for natural regeneration. We analyzed the physico-chemical characteristics of the soil samples collected from 23 pine forests and confirmed the similar results with the forest soil characteristics. Soil pH, organic matter content, total nitrogen, exchangeable Ca, silt content, and exchangeable Al were selected as the major soil factors among the exposed soils through 10 days of pine seedlings exposure and cultivation experiments and statistical analysis. Multiple regression analysis showed that soil pH had a positive effect on specific root length (SRL) of red pine seedlings and exchangeable Al was a significant factor affecting negative change in SRL. Taken together, the reduction of exchangeable Al by soil pH adjustment would be helpful for natural regeneration by restoring the forest and improving the fine root and root integrity of pine seedlings. Therefore, soil pH and exchangeable Al could be recommended as a major soil factor to be carefully considered in the monitoring and management of soil in pine forests that need to be renewed in the future.

Strength characteristic transformation of weathered soil caused by freezing-thawing (동결 -융해에 따른 풍화토의 강도특성 변화)

  • 김수삼;박영목;정승용;김용수
    • Proceedings of the KSR Conference
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    • 2001.10a
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    • pp.520-525
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    • 2001
  • It's strongly recommended to check upon the slope stability of soil nearby railroad, since the freezing-thawing repeat in long term may cause decrease of slope stability. The study is, therefore, focused on the strength characteristic transformation of soil, measuring it experimentally, throughout physical and mechanical tests operated by the freezing-thawing repeat tests. The sampling of weathered soil used for the embankment materials along the domestic railway lines are classified by parent-rock, and then collected after it in the first hand. It tells that Uniaxial strength and axial strain were decreased simultaneously as the frequency of freezing-thawing repeat increased and its range was reduced into 25~85 percentage off comparing to uniaxial strength of unfreezing-soils when about 100 times of freezing-thawing repeats occurred. Following the result of direct shear tests, the cohesion of freezing-soil with freezing-thawing repeats shows 11∼60 percentage less than that of unfreezing-soil but the change of internal friction angle of the soil is extremely slight, enough to ignore. As a result. it could be found that strength characteristic transformation has highly correlated with freezing-thawing repeat.

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A Basic Study for Design and Analysis of the Green Wall System (Green Wall 시스템의 설계 및 해석을 위한 기초연구)

  • Park, Si-Sam;Kim, Jong-Min;Kim, Hong-Taek
    • Proceedings of the Korean Geotechical Society Conference
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    • 2005.10a
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    • pp.681-688
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    • 2005
  • The Green Wall is the highest eco-system among a segmental retaining wall systems. Recently, the demand of high segmental retaining wall (SRW) is increased in domestic. The soil nailing system is applied in order to maintain the high SRW stability for steeper slope. However, the proper design approach that can consider the earth pressure reduction effects in soil nailing system has not been proposed. Hence, the purpose of this study was to provide the design and analysis technique of the segmental retaining wall reinforced by soil nailing. Also, in this study, various parametric studies using numerical method as shear strength reduction (SSR) technique were carried out. In the parametric study, the length ratio and the bond ratio of the soil nailing were changed to identify the earth pressure reduction effect of the retaining wall reinforced by soil nailing.

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A Study on the Apply to Soil Thermal Resistivity of Low-Voltage Underground Power Cables (저압 지중케이블의 토양 열저항률 적용에 관한 연구)

  • Lee, Joo-Chul;Kim, Ki-Hyun;Lee, Young-Chul
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.26 no.5
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    • pp.65-70
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    • 2012
  • The current-carrying capacities in IEC standards for underground refers to a soil thermal resistivity of 2.5[$K{\cdot}m/W$] where no measured data are available. But this value is considered too conservative and may not justifiable economically as to need precaution in using the value. In this paper, the standard practices on the application of soil thermal resistivity of some countries(UK, USA etc) are surveyed and proposed a reasonable representative value 1.0[$K{\cdot}m/W$] of soil thermal resistivity considering the domestic soil thermal properties with regard to the application of IEC standard.

Interpretation of Contaminated Soil by Complex Oil (토양 내 복합유종에 의한 오염 해석 연구)

  • Lim, Young-Kwan;Kim, Jeong-Min;Kim, Jong-Ryeol;Ha, Jong-Han
    • Journal of Soil and Groundwater Environment
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    • v.22 no.1
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    • pp.13-17
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    • 2017
  • Over 30% of domestic soil contamination has occurred via petroleum products and complex oil. Moreover, contamination by complex oil is more intense than it is by a single petroleum product species. In this study, we analyzed sectional TPH (total petroleum hydrocarbon) pattern and sectional ratio of current domestically distributed petroleum products, such as kerosene, diesel, bunker C, and lubricant and complex oils, to determine pollution characteristics of the soil. In the TPH pattern, kerosene, which is a light distillate, had an early retention time, and lubricant oil, which is a heavy distillate, had a late retention time in the gas chromatogram. In addition, we obtained a complexly contaminated soil via diesel and lubricant oil from the Navy and inspected it for its ratio of complex oil species. The inspection results showed that this soil was contaminated with 85% diesel and 15% lubricant oil. The method developed in this study could be used to determine complex petroleum sources and ratios at sites with accidentally contaminated soil.

Evaluation of Soil Properties using Pressuremeter Test (공내재하시험을 이용한 지반정수 평가)

  • 한상연;장서만;전성곤;이종규
    • Proceedings of the Korean Geotechical Society Conference
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    • 2001.03a
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    • pp.175-182
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    • 2001
  • The PMT test results are compared with other in situ test such as Standard Penetration Test (SPT), Cone Penetration Test (CPT), Field Vane Test (FVT) and the laboratory test in order to investigate the correlationships for the strength parameters obtained from Busan and Incheon areas. Many proposed correlation formulas also make a comparative study and new correlation formulas for domestic soils are introduced. Limit pressure ( $P_1$) could be determined by P-log($\Delta$V/V) and Relative volume Method. PMT for the granular soils showed relatively high correlation with SPT, while CPT has good correlation with PMT for cohesive soil. The predicted undrained shear test ( $S_{u}$) by the PMT test results for Incheon and Busan samples showed low correlativity with proposed equations, therefore, new correlation formulas are proposed for domestic soils.s.

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The Current Problems of Chemical Fertilizer Supply and Consumption in Korea (비료수급정책(肥料需給政策)의 현황(現況)과 대책)

  • Kim, Dong-Hi
    • Korean Journal of Soil Science and Fertilizer
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    • v.15 no.1
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    • pp.16-33
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    • 1982
  • The major problems of chemical fertilizer supply and consumption involved in price policies since the end of World War II in Korea and their solutions were extensively discussed. The period was divided into three sub-periods: 1946-1960, 1961-1967 and 1968 to present. Since 1968 when the operations of three large-scaled fertilizer plants: Yongnam Chemical Co., Chinhae Chemical Co. and Hankuk Fertilizer Co. were begun in full scale, the domestic supply of nitrogen and phosphate fertilizers were almost enough for the domestic demand. However, since 1976, when Namhae Chemical Co. was added to the production capacity, the fertilizer industry has been faced with the overproduction problem of nitrogen, and the high production cost due to high petroleum price, which gave financial difficulties. Several policy directions and alternative measures for solving the current problems were also suggested in this presentation.

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Development of Lighting Compressed by Injection Yellow Ocher Soil

  • Kwak, Woo-Seob
    • Journal of the Korea Furniture Society
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    • v.19 no.6
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    • pp.452-459
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    • 2008
  • The compressed injection yellow ocher soil is the process-technology by drying the product through sunshine, not by firing like pottery and ceramic ware. It is the technology of development being able to achieve the far infrared ray and humidity adjustment by adding recycling paper, Korean paper and bamboo salt, and it corresponds with the construction enforcement ordinance 2007 as an interior-finishing product which is fire-resistant. In case that the yellow ocher soil would be used as lighting device and interior-finishing material and decoration, it could contribute to an improvement of National Health by avoiding the sick house syndrome and adding humidity adjustment, and it has more efficient economic effect due to using recycle-available additives. Through such developments of the yellow ocher soil products the domestic market of lighting device and construction material can be advanced and the replacement effect of imported goods & also export effect can be expected accordingly.

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Characterization of Humic and Fulvic Acids Extracted at the Soils of Korea and Its DB Establishment (국내 토양 휴믹물질의 특성 규명 및 DB 구축에 대한 연구)

  • 이창훈;유지호;신현상;정근호;이창우
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2003.04a
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    • pp.397-400
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    • 2003
  • In this study, humic and fulvic acids in soils at the vicinity of domestic atomic power plants(NPPs), located in Yungkwang(YK), Uljin(UJ), Kori(KR), Koseong(KS), Wolseong(WS) area, and in volcanic ash soils of the Cheju island(Mt. Hanla(HL), Manjanggul(MJ)) were isolated, and characterized using chemical(elemental analysis, proton exchange capacity, molecular size distribution) and spectroscopic(UV/Vis., IR, FL, $^{13}$ C NMR spectra) methods. The results were compared with one another and compiled for their DB establishments. The humic substances distribution (humic acid, fulvic acid, Humin) in the soils were also determined by IHSS standard method. Main purpose of this study was to provide a basic data needed to evaluate the effect of humic substances on the migrational behaviour of radioactive elements in contaminated surface soil.

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