• Title/Summary/Keyword: Soil components

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Effect of particle size and scanning cup type for near infrared reflection on the soil property measurement

  • Ryu, Kwan-Shig;Cho, Rae-Kwang;Park, Woo-Churl;Kim, Bok-Jin
    • Near Infrared Analysis
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    • v.1 no.2
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    • pp.35-39
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    • 2000
  • The purpose of this research was to find out suitable soil sample preparation and sample holding tools for NIR reflection radiation for estimating soil components. NIR reflectance was scanned at 2nm intervals from 1,100 to 2,500nm with an InfraAlyzer 500(Bran+Luebbe Co.). Coarse(2.0mm) and fine(0.5mm) soil sample and various sample holding tools were used to obtain mean diffuse reflection of the soil for the calibration and validation of the calibration set in estimating moisture, organic matter and total nitrogen of the soils. Multiple linear regression was used to obtain the best correlation of NIR spectroscopy method. Correlation of NIR spectroscopy method. Correlation of NIR spectra for finely and coarsely sized soil did not show much difference. The standard errors of prediction(SE) using different types of sample holding tools for organic matter, total nitrogen and soil moisture were better than 0.765, 0.041 and 0.63% respectively. From the results it can be concluded that NIR spectroscopy with flow type cell could be used as a fast routine testing method in quantitative determination of organic matter, total nitrogen and soil moisture.

Response of Soil Plug to Seaquake Induced by the Vertical Seismic Excitation (수직 지진 진동에 의해 유발된 해진에 대한 관내토의 거동)

  • 최용규
    • Proceedings of the Earthquake Engineering Society of Korea Conference
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    • 1998.04a
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    • pp.81-88
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    • 1998
  • During an earthquake, there are three main components of excitation : horizontal excitation of the ground, vertical excitation of the pile due to superstructure feedback produced by vertical excitation of the ground, and the seawater excitation induced by the vertical ground shaking, that is, "the seaquake." These excitations could have effects on the soil plugs in open-ended pipe piles installed at offshore sites. In this study, seaquake excitation induced by the vertical ground shaking was simulated by pulsing the water pressure at the seabed. During a seaquake, due to induced excess porewater pressure and pressure gradients in the soil, the capacity of open-ended pipe piles installed in a simulated sea depth of greater than 220 m was reduced serevely and the soil plugging resistance was degraded by more than 80%. The soil plug was failed because of the upward seepage forces that developed in the soil plug due to excess pore water pressure produced in the bottom of the soil plug during the seaquake. The compressive capacity of an open-ended pile in a simulated sea depth of less than 220m was reduced only by about 10%, and the soil plug resistance was degraded by less than 5%.s than 5%.

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Effect of raft and pile stiffness on seismic response of soil-piled raft-structure system

  • Saha, Rajib;Dutta, Sekhar C.;Haldar, Sumanta
    • Structural Engineering and Mechanics
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    • v.55 no.1
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    • pp.161-189
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    • 2015
  • Soil-pile raft-structure interaction is recognized as a significant phenomenon which influences the seismic behaviour of structures. Soil structure interaction (SSI) has been extensively used to analyze the response of superstructure and piled raft through various modelling and analysis techniques. Major drawback of previous study is that overall interaction among entire soil-pile raft-superstructure system considering highlighting the change in design forces of various components in structure has not been explicitly addressed. A recent study addressed this issue in a broad sense, exhibiting the possibility of increase in pile shear due to SSI. However, in this context, relative stiffness of raft and that of pile with respect to soil and length of pile plays an important role in regulating this effect. In this paper, effect of relative stiffness of piled raft and soil along with other parameters is studied using a simplified model incorporating pile-soil raft and superstructure interaction in very soft, soft and moderately stiff soil. It is observed that pile head shear may significantly increase if the relative stiffness of raft and pile increases and furthermore stiffer pile group has a stronger effect. Outcome of this study may provide insight towards the rational seismic design of piles.

Effect of Litter on the Soil Condition(II) Varieties of Soil Fertility due to the Decomposition of Litters on the Soil. (토양조건에 미치는 낙엽의 영향(제2보) 낙엽부패에 의한 토양성분 변화)

  • 차종환
    • Journal of Plant Biology
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    • v.12 no.1
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    • pp.15-21
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    • 1969
  • In this experiment, the litters of each five species of neadle-leaf trees and broad-leaf trees were laid on each pot soils, which had same soil conditions, is the green house and the sil fertility of each pots were determined after four years. Chemical properties among each pot soils under litters of needle-laef trees showed remarkable different values in the pH, base exchange capacity, total exchangeable base, base saturation, organic matter, available phosphorus, exchangeable potassium and calcium, and that of broad-leaf trees showed respectively significant difference. The content of chemical components, such as total exchangeable base, organic matter, total nitrogen, available phosphorus and exchanbeable potassium, between pot soils under litters of the needle-leaf trees and the broad-leaf trees were significant at the 0.01 and 0.05 levels of the statistical probability. The fertility of soil under the influence of decayed fallen leaves is the highest value in the posts of broad-leaves and next to the pots of needle-leaves and the control pots the lowest. The pH value of the soil with various kinds of fallen leaves showed little difference among themselves, but it especially approached in the broad leaves plots gradually to neutral and hte non-treated plot showed acidity. Lespedeza bicolar and Castanea crenata are supposed to contribute to the fertility of soil. Pinus rigida showed excellent exchanged properties of soi. The leaves of Robinia pseudoacacia and Pinus koraiensis did not contribute much to the promotion of fertility of soil.

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Response and transcriptional regulation of rice SUMOylation system during development and stress conditions

  • Chaikam, Vijay;Karlson, Dale T.
    • BMB Reports
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    • v.43 no.2
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    • pp.103-109
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    • 2010
  • Modification of proteins by the reversible covalent addition of the small ubiquitin like modifier (SUMO) protein has important consequences affecting target protein stability, sub-cellular localization, and protein-protein interactions. SUMOylation involves a cascade of enzymatic reactions, which resembles the process of ubiquitination. In this study, we characterized the SUMOylation system from an important crop plant, rice, and show that it responds to cold, salt and ABA stress conditions on a protein level via the accumulation of SUMOylated proteins. We also characterized the transcriptional regulation of individual SUMOylation cascade components during stress and development. During stress conditions, majority of the SUMO cascade components are transcriptionally down regulated. SUMO conjugate proteins and SUMO cascade component transcripts accumulated differentially in various tissues during plant development with highest levels in reproductive tissues. Taken together, these data suggest a role for SUMOylation in rice development and stress responses.

[ PM10 ] Concentration and Chemical Composition in a Western Region of Susan during the Spring 2003 (2003년 봄철 부산 서부지역의 PM10 농도 특성과 화학적 조성)

  • Jeon Byung-Il;Hwang Yong-Sik
    • Journal of Environmental Science International
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    • v.14 no.5
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    • pp.463-471
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    • 2005
  • This study is designed to investigate the characteristics of $PM_{10}$ concentration and the chemical composition of heavy metallic components in the $PM_{10}$ sampled in western Busan from March to May, 2003. $PM_{10}$measurement was done during springtime of 2003, totaling 29 days: 9 days in March, 10 days in April and 10 days in May. With a sampling time of 24 hours, it started 9:00 AM on that day and ended 9:00 AM the next day. The mean contribution ratio of soil during springtime was $10.3\%$. Al had a significant correlation with Ca, Fe, Mg and Si and little correlation with Na, Ni and Zn.

Fall Performance of Korean Lawngrass (Zoysia japonica Steud.)as affected by Bio -fertilizer Application (발효계분비료시용이 들잔디(Zoysia japonica Steud.)의 추계생장양상에 미치는 영향)

  • 심재성;정원일
    • Asian Journal of Turfgrass Science
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    • v.4 no.2
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    • pp.77-83
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    • 1990
  • The effect of bio-fertilizer, which was manufactured poultry manure, on the fall performance of Korean lawngrass was determined on a clay loam soil. Plant length was characterized by increasing the amount of bio-fertilizer applied. This trend was also true in dry matter yield of tops during the experimental period from August 31 through October 30. Both tiller numbers and stolon length steadily increased with increasing amount of bio-fertilizer applied, and 40m/t application of bio-fertilizer was found to be most effective on both components. performance shown on November 5 was prominent for both green leaf and root weights when the increased amount of bio-fertilizer was applied. Korean lawngrass had three times as much green leaf weight with 40m/t application of bio-fertilizer as with other treatments. Several functions of increment of above- ground part components caused by increasing root weight, which is greatly affected by bio-fertilizer application, was discussed. Turf quality was much improved by applying bio-fertilizer, indicating that this fertilizer might play an improtant role in respect of soil structure, water retention etc.

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Cuboidal Infinite Elements for Soil-Structure-Interaction Analysis in Multi-Layered Half-Space (3차원 지반-구조물 상호작용해석을 위한 입방형 무한요소)

  • Seo, Choon-Gyo;Yun, Chung-Bang;Kim, Jae-Min
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.20 no.1
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    • pp.39-50
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    • 2007
  • This paper presents 3D infinite elements for the elastodynamic problem with multi-layered half-space. Five different types of infinite elements are formulated by using approximate expressions of multiple wave components for the wave function in multi-layered soil media. They are horizontal, horizontal-corner, vortical, vertical-corner and vertical-horizontal-comer infinite elements. The elements can effectively be used for simulating wane radiation problems with multiple wave components. Numerical example analyses are presented for rigid disk, square footings and embedded footing on homogeneous and layered half-space. The numerical results show the effectiveness of the proposed infinite elements.

Feasibility Study of Agronomic Application of Treated Sewage for Paddy Rice Culture

  • Woo, Sun-Ho;Yoon, Chun-Gyeong
    • Korean Journal of Environmental Agriculture
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    • v.19 no.5
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    • pp.433-441
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    • 2000
  • A feasibility study was performed to examine the agronomic application of treated sewage on paddy rice culture by field experiment for two consecutive years. The domestic sewage was treated by the constructed wetland system which was in subsurface flow type and consisted of sand and macrophyte. The effluent of the wetland system was used for irrigation water. The effluent was diluted to maintain the total nitrogen concentration below $26mg{\cdot}L^{-1}$ in the first year and used without dilution in the second year experiment. Growth components and yields were compared against the CONTROL plot where conventional method was applied. And also, soil characteristics of the plots before and after reclaimed sewage irrigation were analyzed. Generally, addition of the treated sewage to the irrigation water showed no adverse effects on paddy rice culture, and even enhancement was noticed in both growth and yield. Irrigation of treated sewage after concentration adjusted with conventional fertilization showed the better result, and the yield exceeded that of CONTROL case where clean water was irrigated. Soil characteristics changed after irrigation, and significant EC increasing was observed for the reclaimed sewage irrigation plots. From this study, it appears that reuse of treated sewage, as supplemental irrigation water could be a feasible and practical alternative. For full-scale application, further study is recommended on the specific guideline of major water quality components in treated sewage for irrigation and public health.

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Analysis of Ecohydrologic Characteristics based on Development of Riparian Zone (수변 식생대 조성에 따른 생태수문학적 특성 분석)

  • Kim, Nam Won;Kim, Jitae;Chung, Il Moon;Lee, Jeongwoo
    • Journal of Korean Society on Water Environment
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    • v.25 no.6
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    • pp.910-915
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    • 2009
  • The ecohydrologic characteristics according to planting in riparian zone for the riparian restoration are analyzed in this research. The ecohydrologic components due to land use change in riparian zone from existing land cover to planted area such as pasture and wildrye are simulated in the test basin with the integrated SWAT-MODFLOW model. After analysis of change of the hydrologic properties such as surface flow, lateral flow, transpiration and soil water in riparian zone, it is revealed that soil water is one of the key factors and planting of wildrye can increase soil water in riparian zone. The simulation performance of the SWAT-MODFLOW model is validated in this study and it is expected that this model can be used to evaluate various riparian restoration scenarios.