• Title/Summary/Keyword: soil materials

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Characteristic of organic/inorganic composite formed grounding resistance lowering agents (유/무기 복합재료형 접지저감제의 특성)

  • Kim, Jang-Wook;Chung, Chul-Hee;Cho, Dae-Hoon
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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    • 2004.05a
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    • pp.74-80
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    • 2004
  • Among inorganic materials, it is grounding resistance lower agent of new form that use being strata style clay and makes using water soluble polymer by main material to organic substance. Water soluble polymer chains are dispertion in water because water soluble polymer reacts with water if is done and these discrete polymer chains are inserted to floor of being strata style clay with water. This material that moisture content is very excellent and rate of expansion, electrical conductivity that measure after supplies water of 300wt % as well as is excellent. Can prevent corrosion or electrolytic corrosion of grounding bar securing very environmentally, chemically and pollution of soil. When applied to general grounding rod worker $7{\sim}8$ times ground resistance reduction effect of not application.

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A Study on Conservation of the Natural Environment in Chosun-Dynasty, Korea (조선시대 자연환경보전에 관한 연구)

  • 오승봉;안동만
    • Journal of the Korean Institute of Landscape Architecture
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    • v.23 no.1
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    • pp.51-65
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    • 1995
  • Conservation of the natural environiment In chosun-Dynasty, Korea, is analysed on the basis of the of official records of the king's offices(Chosun-wangjo-sillok). In the popular ideologies of the dynasty, Seongleehak(philosophy of humanity arid natural laws) and Pungsu (geomancy) , the naturnal enviroment is defined as an entity con-sisting of Cheon (heaven) , San(mnountains) , Su (water), Geumsu (animals)and Chomok (plants) .the notion of Tacksi-Tackmul(being careful to take natural resources at the right time) was one of the Cheonmyung (eavenly decrees) . It was believed that violation of this principle resulted in natural disasters. Sasan(four mountains surrounding Hansungbu-, the capital city, now Seoul) , were strictly preserved according to geomancy practices. In areas other than the capital city, Sanlimcheontack (mountains, forests, rivers and ponds) were con-served for sustained production of building materials especially pinetrees for ship building, foods, firewoods, horses, and orter useful natural resources. Various conservation policy insturuments were adopted. Prunning trees was permitted only in October. Capturing fishes was allowed only after the spawning period. Protection areas were designated in Sasan, Seongjoesiplee (surroundings of the capital city) , Geumsan(protected mountains), Kangmujang(hunting and army training grounds), Sijang(firewood areas), Mokmajang(horse ranches) and Neungyuk(royal tombs) . Activities prohibited for conservation purposes included cutting timbers, burning, building houses or tombs, dumping wastes, farming and breaking up fresh land, grazing, hunting and trespassing. Positive actions for conservation were rituals to Heaven ennoblement of natural elements such as mountians or rivers, planting trees, Boto (supplementing soil on low ridges) , Josan (mounding) and making ponds. Boto, Josan and making ponds were to make ideal terrains for geomancy. Many government bodies and civil servants were engaged in the conservation activities. For example, Sanjik(forest keeper) was a special position with responsibility for forest management.

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Use of Arundinaria munsuensis Y. Lee as Revegetation Plant Materials of Damaged Slopes (훼손지 비탈면 녹화용 식물소재로의 문수조릿대의 적용성 연구)

  • Jang, Hyung-Tae;Park, Won-Je;Kim, Nam-Choon;Park, Jong-Min
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.15 no.1
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    • pp.133-140
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    • 2012
  • The study of Arundinaria munsuensis Y. Lee to this day was limited to the field of morphological species classification since its first discovery at Jiri mountain in the late 1990s. This native plants, one of Korean endemic species found in Jiri Mt. necessitates further studies about its use as revegetation plants or groundcover plants in urban areas. This study was launched from this need followed by summaries of results below related to its usage. This targeted species is a native Korean species which its natural distribution on the subalpine zone has merit for the wide range of climatic adaptation. Also, the coverage rate reached 78.3% in three years mostly by rhizome growth with an expectation of full coverage in four years providing less maintenance needs after planting. The net price for the construction of pot seedling methods of this plants is relatively economical than other normal revegetation construction methods. For these reasons, drilling for the plants on cut and fill soil slopes driven from pot seedling adapts Arundinaria munsuensis Y. Lee as efficient revegetation plant. Total construction cost for pot seedling work($30cm{\times}30cm$) of Arundinaria munsuensis was approximately 21,000won which is in reasonable price range when compared to other revegetation construction methods of disturbed slopes. As a native Korean plant, Arundinaria munsuensis has wide range of climatic adaptation with less maintenance requirement after planting. This study may suggest a strong possibility of Arundinaria munsuensis as a pot planting material in sloped area.

The Effects of the Seed Inoculation, Pelleting, and Liming on the Nodulation and Growth of Lucerne(Medicago sativa L.) (황갈색 고원 토양에 있어 근류균 접종, pellleting 및 석회시용이 Lucerne(Medicago sativa L.)의 근류형성 및 생육에 미치는 영향)

  • 임병기
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.10
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    • pp.79-83
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    • 1971
  • To investigate the effects of seed treatments and liming on nodulation and growth of lucerne(Medicago sativa L.) in an upland yellow-brown earth in N.Z. the five levels of seed treatments(Uninoculated, Inoculated, Inoculated plus lime pelleted, Inoculated plus 50/50 phosphate/dolmite pelleted, Inoculated plus ta1c pelleted), and 2 levels of lime applications (0, 25kg/10a) were compared and their interactions were observed, and then the following results were obtained. 1. In oder to obtain the effective nodulation of lucerne on acid soil it is usually necessary to apply lime and inoculate the seed. 2. The coating of inoculated lucerne seed with adequate materials will promote the nodulation. 3. The pelleting of lucerne seed may be a of reducing the need for the heavy liming. 4. The finely grounded lime was the best to use origin upland yellow-brown earth. 5. When the seed were not inoculated or pelleted with inferior material, liming is very effective for the nodulation and growth of lucerne. 6. The pelleting seed will reduce the laborious work and expenditure.

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Improvement of Herbicide Use in Crop Production w. Growth Responses of Soybean (Glycine max) Cultivars to Application Time of Metribuzin Herbicide (제초제의 사용법 개발에 관한 연구 제4보 Metribuzin 사용시간에 따른 대두품종의 생육반응)

  • 구자옥;정순주;이종영
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.26 no.2
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    • pp.179-184
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    • 1981
  • The study was conducted to know the differential growth responses of soybean cultivars as affected by various application stages of Metribuzin herbicide, at the University experimental farm of Chonnam Nat'l. Univ, Kwangjoo, 1980. Experimented soybean materials were six cultivars, as Kwanggyo, Dongbuktae, Bongui, Yukwoo 3, Suweon 85, and Suweon 86., . and Laid-out application stages were five as pre-sowing, Pre-emergence, Early Post-emergence, and Late Post-emergence treatment comparing with Control. Results obtained from the study were as follows: Among experimented soybean cultivars, no significantly tolerant cultivar was shown. Highly significant differences in phytotoxicities by Metribuzin treatments were detected among various application stages, and crop tolerances were recognized bigger in order as E. Post-emg. < L. Post-emg. $\ll$ Pre-emg. < Pre-sowing $\leq$ Control. The phytotoxic symptoms of all soybean cuitivars were severely recorded in order of Leaf No. /Plant < Plant height $\ll$ Branch No. /Plant. For the cultivation of most soybean cuitivars, the use of Metribuzin in Pre-sowing or Pre-emergence were recommended, and especially it is expected to follow of more detailed study on soil-incorporation method in Pre-sowing treatment, and rather the tank-mixture system of Metribuzin with others than the mono-application system for the safe-use and enlargement of weeding-spectrum.

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Logging for a Stone Column Using Crosshole Seismic Testing (크로스홀 탄성파 시험을 이용한 쇄석말뚝의 검측)

  • Kim, Hak-Sung;Mok, Young-Jin
    • International Journal of Highway Engineering
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    • v.12 no.4
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    • pp.139-145
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    • 2010
  • An integrity testing for stone columns was attempted using crosshole S-wave logging. The method is conceptionally quite similar to the crosshole sonic logging (CSL) for drilled piers. The critical difference in the logging is the use of S-wave rather than P-wave, which is used in CSL, because swave is the only wave sensing the stiffness of slower unbounded materials than water. An electro-mechanical source, which can generate reversed Swave signals, was utilized in the logging. The stone column was delineated using the S-wave travel times across the stone column, the S-wave velocity profile of the crushed stone($V_{cs}$-profile) and that of surrounding soil($V_s$-profile). In the calculation of $V_{cs}$-profile of the crushed stone, its friction angle and Ko (coefficient of lateral earth pressure at rest) are recommended to be used. The calculation of the column diameter is not much affected by the values of friction angle and Ko.

Retrieval of Key Hydrological Parameters in the Yellow River Basin Using Remote Sensing Technique

  • Dong, Jiang;Jianhua, Wang;Xiaohuan, Yang;Naibin, Wang
    • Proceedings of the KSRS Conference
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    • 2002.10a
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    • pp.721-727
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    • 2002
  • Precipitation evapotranspiration and runoff are three key parameters of regional water balance. Problems exist in the traditional methods for calculating such factors , such as explaining of the geographic rationality of spatial interpolating methods and lacking of enough observation stations in many important area for bad natural conditions. With the development of modern spatial info-techniques, new efficient shifts arose for traditional studies. Guided by theories on energy flow and materials exchange within Soil-Atmosphere-Plant Continuant (SPAC), retrieval models of key hydrological parameters were established in the Yellow River basin using CMS-5 and FengYun-2 meteorological satellite data. Precipitation and evapotranspiration were then estimated: (1) Estimating tile amount of solar energy that is absorbed by the ground with surface reflectivity, which is measured in the visible wavelength band (VIS): (2) Assessing the partitioning of the absorbed energy between sensible and latent heat with the surface temperature, which was measured in the thermal infrared band (TIR), the latent heat representing the evapotranspiration of water; (3) Clouds are identified and cloud top levels are classified using both VIS and TIR data. Hereafter precipitation will be calculated pixel by pixel with retrieval model. Daily results are first obtained, which are then processed to decade, monthly and yearly products. Precipitation model has been has been and tested with ground truth data; meanwhile, the evapotranspiration result has been verified with Large Aperture Scintillometry (LAS) presented by Wageningen University of the Netherlands. Further studies may concentrate on the application of models, i.e., establish a hydrological model of the Yellow river basin to make the accurate estimation of river volume and even monitor the whole hydrological progress.

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A Study of Dewatering and Filtration on Woven Geotextile Tube (직포 지오텍스타일 튜브의 여과와 탈수에 대한 연구)

  • Kim, Tae-Hyung;Jung, Soo-Jung
    • Journal of the Korean Geosynthetics Society
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    • v.5 no.2
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    • pp.31-37
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    • 2006
  • The purposes of this paper are to study the use possibility of geotextile tubes for dewatering of high water content sludges and sediments and to evaluate affecting factors on dewatering. To do this, pressure filtration tests are conducted on four high water content materials with two geotextiles under two filtration pressures. Based on the test results, although woven geotextile tubes are not satisfied the soil retention criteria used in filter design commonly, a great portion of fines are retained by filter cake formation on geotextile tube's upstream side, but also after formation of filter cake, the permeability drops sharply. Higher filtration pressure tends to increase dewatering rate, but has very little effect on filtration efficiency. Dewatering capacity is affected by several factors which are related to the geotextile, but the property of sludge appears to be the dominant control factor for dewatering efficiency.

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Electrokinetic Extraction of Pollutants from the Vicinity of Unregulated Landfill Site (동전기적 추출에 의한 비위생매립지 주변 오염지반의 정화)

  • Lee, MyungHo;Chung, Ha-Ik
    • Journal of the Korean Geosynthetics Society
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    • v.5 no.2
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    • pp.17-22
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    • 2006
  • This paper presents preliminary field investigations on the electrokinetic (EK) remediation coupled with permeable reactive barrier (PRB) system. unregulated and old-fashioned landfills are one of the primary contributors to various contaminated soil problems. In-situ EK remediation technology has been successfully applied to the environs of unregulated landfill site, located in Kyeong-Ki province, Korea. Atomizing slag was adopted as a PRB reactive material for the remediation of groundwater contaminated with inorganic and/or organic substances. From the preliminary investigations, the coupled technology of EK with PRB system would be effecitve to remeidate contaminated grounds without the extraction of pollutants from subsurface due to the reactions between the reactive materials and contaminants.

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Effect of Organic Fertilizer and Mulch Sources on Growth and CO2 Assimilation in MM.106 Apple Trees (유기질 비료와 멀칭자재가 MM.106 사과 대목의 생장과 광합성에 미치는 영향*)

  • Choi, Hyun-Sug;Rom, Curt;Kim, Wol-Soo;Choi, Kyeong-Ju;Lee, Youn
    • Korean Journal of Organic Agriculture
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    • v.18 no.2
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    • pp.245-255
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    • 2010
  • The study was conducted to investigate the effects of organic fertilizers and mulches on the growth and $CO_2$ assimilation in MM.106 apple trees. Growth and $CO_2$ assimilation of MM.106 apple trees grown in a greenhouse were affected by the nutrient concentrations and carbon (C) and nitrogen (N) ratio in the raw materials of organic fertilizers and mulches. The optimum C:N ratios, which makes microorganism convert the organic N into the inorganic N, were obtained in the organic fertilizer, poultry litter, green compost, and grass clippings, resulting in increasing single shoot height, SPAD, and $CO_2$ assimilation. The SPAD and $CO_2$ assimilation were affected by the treatments 5 weeks after the treatments, and then the tree growth was affected by the treatments 6 weeks later. The most efficient tree growth and development were observed in the 10 to $15\;mg{\cdot}kg^{-1}$ of the inorganic N in a soil, and the N was strongly related to the tree growth and development.