• 제목/요약/키워드: TOP SOIL

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현장 조건에 따른 Top-Down 공법 사례분석에 관한 연구 (Analysis of Cases Using Top-Down Construction Method Under Various Site Condition)

  • 신현정;신규철
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2011년도 춘계 학술논문 발표대회 1부
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    • pp.197-199
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    • 2011
  • To utilize the Top-Down construction method, it is required to analyse building area, floors, and soil conditions to choose the three basic elements of retaining wall, base column, and floor structure. The purpose of this research is to compare the methods of Top-Down with other construction methods. The research method is to analyse the project conditions of Top-Down project cases. The aim is to develop a method of selecting alternatives, considering construction characteristics, work schedule, supporting methods, foundation types.

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산불이 임지(林地)의 수저류(水貯留) 특성(特性)에 미치는 영향(影響) (Effects of Forest Fire on the Water Storage Characteristics of Forest Land)

  • 이헌호
    • 한국산림과학회지
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    • 제85권1호
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    • pp.66-75
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    • 1996
  • 본 연구는 산불 발생이 임지의 수저류 특성에 미치는 영향을 알아보기 위해 실시했다. 비산불 지역과 산화적지를 대상으로 산림토양의 수저류능을 토양공극, 최대수분량, 이용가능수량, 그리고 투수율을 측정하여 비교 분석하였다. 주요 인자들의 측정에 의해서 얻어진 결과는 다음과 같다. 산화적지와 대조구에서 토성이 깊어질수록 전공극(全孔隙), 조공극(組孔隙), 이용가능 수량, 투수율은 모두 감소하는 경향을 나타내고, 세공극(細孔隙)은 약간 증가하는 경향이 있었다. 대조구에 비해 산화적지에서는 투수율, 조공극량 및 이용가능수량이 낮게 나타나는 반면, 세공극량은 높게 나타났다. 그리고 산불이 발생한 직후에는 산림토양의 공극량 분포에 큰 변화가 일어나지 않지만, 시간이 경과함에 따라 산화적지의 표토 공극분포에 변화를 일으키면서 서서히 토심 20-40cm까지 영향을 미치는 것으로 나타났다. 또한 토심변화에 따른 이용가능수량의 변화는 대조구에 비해 산화적지에서 상대적으로 큰 폭으로 감소하는 경향이 있었다. 이 결과로 산림의 수저류능은 산불에 의해 크게 영향을 받는 것을 알 수 있었다.

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Comparison of Heavy Metal(loid)s Contamination of Soil between Conventional and Organic Fruit Farms

  • Lee, Hyun Ho;Kim, Keun Ki;Lee, Yong Bok;Kwak, Youn Sig;Ko, Byong Gu;Lee, Sang Beom;Shim, Chang Ki;Hong, Chang Oh
    • 한국토양비료학회지
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    • 제50권5호
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    • pp.401-408
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    • 2017
  • Organic amendments such as animal waste compost, lime-bordeaux mixture, and lime sulphur mixture contain heavy metal(loid)s which are toxic to human being, animal, and plant. The objective of this study was to compare heavy metal(loid)s contamination of soil between conventional and organic farm. Soil samples were collected from 10 conventional and 38 organic fruit farms. At each sampling point, top (0~15 cm) and sub soil (15~30 cm) were taken using hand auger. Total concentration for arsenic (As), cadmium (Cd), copper (Cu), nikel (Ni), lead (Pb), and zinc (Zn) in the collected soil were measured. The pollution index (PI) for heavy metal in organic farms indicated it was unpolluted area. However, mean value of PI for organic farms (0.143) was higher than that for conventional farms (0.122). High Geoaccumulation index (Igeo) for Cu, Pb, and Zn implied that grape farms were more polluted than others fruit farms because a lot of lime-bordeaux mixture and lime sulphur were applied in organic grape farms. Especially, top soils showed higher level of contamination than sub soil. Based on the above results, organic amendments might cause accumulation of heavy metals in soil. Therefore, particular attention should be paid for concentration of Cu, Pb, and Zn, when organic amendments are used in the organic fruit farms.

제주도(濟州道) 토양(土壤)의 화학적(化學的) 특성(特性) 조사(調査) 연구(硏究) -III. 감귤원(柑橘園) 토양(土壤)에서의 알루미늄 특성(特性) (Chemical Characteristics of Soils in Cheju Island -III. Aluminum Composition of the Citrus Orchard Soils)

  • 유순호;송관철
    • 한국토양비료학회지
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    • 제17권2호
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    • pp.167-172
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    • 1984
  • 제주도(濟州道) 화산회토(火山灰土)에서 감귤원(紺橘園)의 경작년대(耕作年代)에 따른 Al 함량(含量) 변화(變化)를 검토(檢討)하고, Al 함량(含量) 변화(變化)에 영향을 끼치는 요인(要因)들에 관하여 고찰(考察)한 결과(結果)는 다음과 같다. 1. 활성(活性) Al 함량(含量)이 매우 높았는데, 심토(深土)에서 특(特)히 높았다. 그러나 치환성(置換性) Al 함량(含量)은 비교적(比較的) 낮아 활성(活性) Al 함량(含量)의 1/10 정도에 불과(不過)하였다. 2. 감귤원(柑橘園)의 경작년대(耕作年代)가 오래될수록 pH가 증가(增加)함에 따라 치환성(置換性) Al 함량(含量)이 감소(減少)되었다. 3. 감귤원(柑橘園)의 경작년대(耕作年代)가 오래될수록 활성(活性) Al 함량(含量)도 현저하게 감소(減少)되고 있는데, 이는 주(主)로 인산비료(燐酸肥料)의 다량(多量) 시용(施用)에 의(依)해 Al 활성(活性)이 감소(減少)되었기 때문이다. 4. 유효인산(有效燐酸) 함량(含量)이 극(極)히 낮은 심토(深土)에서는 활성(活性) Al이 유기물(有機物) 함량(含量) 및 pH(NaF)와 고도(高度)로 유의(有意)한 상관을 보였으나, 유효인산(有效燐酸) 함량(含量)이 높은 표토(表土)에서는 상관이 낮았다. 이에서 수산화물(水酸化物)의 형태(形態)로 존재(存在)하고 있는 Al이 활성(活性) Al으로 침출(浸出)되고, 인산비료(燐酸肥料)를 시용(施用)하였 때 활성(活性) Al이 시용(施用) 인산(燐酸)과 반응(反應)하여 불용화(不溶化)됨을 알 수 있다.

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토양 질산태질소 함량에 따른 시설 잎들깨 질소 웃거름시비량 추천 (Recommendation of the Amount of Nitrogen Top Dressing based on Soil Nitrate Nitrogen Content for Leaf Perilla (Perilla frutescens) under the Plastic Film House)

  • 강성수;이주영;성좌경;공효영;정형진;박장환;윤여욱;김명숙;김유학
    • 한국토양비료학회지
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    • 제44권6호
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    • pp.1112-1117
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    • 2011
  • 재배기간이 긴 잎들깨 시설 촉성재배 조건에서 질소시비 수준별 시험을 통하여 토양의 질산태질소 함량에 따른 질소 웃거름시비량 결정기준을 설정하였다. 잎들깨 주산단지인 금산과 밀양 두 지역에서 각각 1개의 시설하우스에서 질소시비량 5수준과 관행구를 난괴법 3반복과 4반복으로 각각 실시하였다. 생육시기별로 매달 건물중과 질소흡수량, 마디생장량을 조사하였고, 토양질산태질소를 분석하였다. 금산포장의 마디당 질소 요구량은 $2.2kg\;10a^{-1}$, 밀양포장은 $3.5kg\;10a^{-1}$로 조사되었다. 토양질산태질소의 하한기준은 금산포장과 밀양포장 모두 $NO_3$-N $10mg\;kg^{-1}$로 설정하였다. 상한기준 설정은 토심 15 cm, 용적밀도 $1.2Mg\;m^{-3}$, 토양 중 질산태질소의 이용율 70%를 적용하여 잎들깨 1마디에 필요한 질소요구량을 충족하는 수준으로 결정하여 금산포장과 밀양포장 각각 $30mg\;kg^{-1}$$40mg\;kg^{-1}$로 설정하였다. 따라서 금산지역은 Y=-0.157X + 4.71에 의해, 밀양지역은 식 Y=-0.1667X + 6.6667에 의해 잎들깨 1마디 생육에 필요한 질소 웃거름 시비량을 결정할 수 있었다.

Technique for Soil Solution Sampling Using Porous Ceramic Cups

  • Chung, Jong-Bae
    • Applied Biological Chemistry
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    • 제41권8호
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    • pp.583-586
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    • 1998
  • Porous ceramic cups are used for monitoring ion concentration in soil solutions in various time course and depth. A soil solution sampler was constructed in laboratory by inserting pliable perfluoroalkoxy(PFA) tubings into porous cup through holes in PVC rod segment which plugged top opening of the porous cup. The system was installed in drip irrigated soil in a vertical position, and nitrogen movement below the drip basin was monitored. To collect soil solution, vacuum in the cup was applied with a hand vacuum pump. The samples obtained were sufficient enough to run quantitative analyses for a number of chemicals. Nitrogen transformation and movement could be well defined, and the system seemed to be relevant to the other soil solution samplers in monitoring chemical movement in soil. Although this system has general deficiencies found in the other samplers using ceramic cup, it could be easily constructed at a low cost. Since the tubing was pliable, the cups could be installed in horizontal position, and this allows installations of the cups at more precise depth increments and also more precise samplings of soil solution at each depth.

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Soil-structure interaction and axial force effect in structural vibration

  • Gao, H.;Kwok, K.C.S.;Samali, B.
    • Structural Engineering and Mechanics
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    • 제5권1호
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    • pp.1-19
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    • 1997
  • A numerical procedure for dynamic analysis of structures including lateral-torsional coupling, axial force effect and soil-structure interaction is presented in this study. A simple soil-structure system model has been designed for microcomputer applications capable of reflecting both kinematic and inertial soil-foundation interaction as well as the effect of this interaction on the superstructure response. A parametric study focusing on inertial soil-structure interaction is carried out through a simplified nine-degree of freedom building model with different foundation conditions. The inertial soil-structure interaction and axial force effects on a 20-storey building excited by an Australian earthquake is analysed through its top floor displacement time history and envelope values of structural maximum displacement and shear force.

Comparison of NERICA and Asian rice among traits relevant to drought resistance in the field and the effects of compost

  • Fujii, Michihiko
    • 한국작물학회:학술대회논문집
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    • 한국작물학회 2017년도 9th Asian Crop Science Association conference
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    • pp.335-335
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    • 2017
  • Recently NERICA (New Rice for Africa) was developed by a crossing of African rice (Oryza glaberrima Steud.) and Asian rice (Oryza sativa L.) in West Africa, and is considered to be drought resistant, but drought resistance of NERICA and differences between Asian rice are not clarified enough. In this research, NERICA (four cultivars and two lines), Asian rice (three cultivars and sativa parent of NERICA) and African rice (glaberrima parent of NERICA) were cultivated in the field in Shizuoka University under drought and traits of each cultivar and line relevant to drought resistance, stomatal conductance by porometer, soil water content of individual depths by TDR method, SPAD values by SPAD meter and leaf thickness by micrometer, were measured and compared with dry matter production and yield. Effects of compost were also compared among sativa parent, one NERICA cultivar and two NERICA lines. Glaberrima parent showed highest top dry weight. One NERICA line, one drought resistant Asian rice cultivar and sativa parent, showed higher top dry weight and yield (ear weight) than other Asian rice cultivars and NERICA cultivars and line tested. Compost tended to increase top dry weight and yield in one of NERICA line and sativa parent. But in one NERICA cultivar and line, top dry weight and yield were not increased. In one of Asian rice, one of NERICA line and sativa parent that showed high top dry weight and yield, stomatal conductance was high. On the contrary the glaberrima parent and in other NERICA cultivars and line it was low. In sativa parent compost increased stomatal conductance but in NERICA cultivar and lines it was not. Among cultivars and lines that showed high top dry weight and yield sativa parent and one of NERICA line SPAD value and leaf thickness were high but in one of Asian rice and glaberrima parent they were low. Cultivar and line differences in yield and top dry weight among Asian rice and NERICA were significantly correlated with those in stomatal conductance ($r=0.778^{**}$ and $r=0.654^*$, respectively) and those in leaf thickness ($r=0.600^*$ and $r=0.640^*$, respectively). In Asian rice cultivars average soil water content was significantly correlated with yield ($r=0.886^*$) but in NERICA cultivars and lines it was not significant correlated (r= -0.256). Cultivar and line differences in leaf thickness were significantly correlated with SPAD value ($r=0.773^{**}$). In Asian rice cultivars it was significantly correlated ($r=0.962^{**}$), but in NERICA cultivars and lines it was not significantly correlated (r=0.559). Asian rice cultivars tended to consume soil water to increase yield but in NERICA cultivars and lines the tendency was not clear. Correlation between SPAD value and leaf thickness was different between Asian rice and NERICA cultivars and lines, and in Asian rice cultivars it was significantly correlated but in NERICA cultivars and lines it was not significant. Importance of maintaining high stomatal conductance by high leaf thickness was clarified.

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금정광산 주변 토양의 중금속 오염현황 및 그 처리 방안

  • 이기철;이승길;한인호;최광호;정덕영
    • 한국지하수토양환경학회:학술대회논문집
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    • 한국지하수토양환경학회 1998년도 공동 심포지엄 및 추계학술발표회
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    • pp.189-194
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    • 1998
  • Geochemical study was carried out to find out the distribution of metals and cyanide in soil in the vicinity of the abandoned Keum-Jung mine. Chemical analysis showed that content of As in soil around tailings exceeded 15mg/kg, Korean standard of soil contamination in the farm land. That means the contamination of soil by As is due to input of tailings. According to total decomposition of tailings, As was highly concentrated in tailings. However the water in tailings impoundment was changed to acidic and contaminated by metal and sulfate because the tailings in the top of the tailings impoundment had been oxidized. Acid mine drainage contaminated the water course in the vicinity of the paddy soils. The proper measures are required to prevent contamination of the soil and water in the vicinity of the Keum-Jung mine.

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Evaluation of the Amount of Nitrogen Top Dressing Based on Ground-based Remote Sensing for Leaf Perilla (Perilla frutescens) under the Polytunnel House

  • Kang, Seong-Soo;Sung, Jwa-Kyung;Gong, Hyo-Young;Jung, Hyung-Jin;Kim, Yoo-Hak;Hong, Soon-Dal
    • 한국토양비료학회지
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    • 제49권5호
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    • pp.598-607
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    • 2016
  • This study was conducted to evaluate the amount of nitrogen (N) top dressing based on the normalized difference vegetation indices (NDVI) by ground based sensors for leaf perilla under the polyethylene house. Experimental design was the randomized complete block design for five N fertilization levels and conventional fertilization with 3 and 4 replications in Gumsan-gun and Milyang-si field, respectively. Dry weight (DW), concentration of N, and amount of N uptake by leaf perilla as well as NDVIs from sensors were measured monthly. Difference of growth characteristics among treatments in Gumsan field was wider than Milyang. SPAD-502 chlorophyll meter reading explained 43.4% of the variability in N content of leaves in Gumsan field at $150^{th}$ day after seedling (DAS) and 45.9% in Milyang at $239^{th}$ DAS. Indexes of red sensor (RNDVI) and amber sensor (ANDVI) at $172^{th}$ day after seedling (DAS) in Gumsan explained 50% and 57% of the variability in N content of leaves. RNDVI and ANDVI at $31^{th}$ DAS in Milyang explained 60% and 65% of the variability in DW of leaves. Based on the relationship between ANDVI and N application rate, ANDVI at $172^{th}$ DAS in Gumsan explained 57% of the variability in N application rate but non significant relationship in Milyang field. Average sufficiency index (SI) calculated from ratio of each measurement index per maximum index of ANDVI at $172^{th}$ DAS in Gumsan explained 73% of the variability in N application rate. Although the relationship between NDVIs and growth characteristics was various upon growing season, SI by NDVIs of ground based remote sensors at top dressing season was thought to be useful index for recommendation of N top dressing rate of leaf perilla.