• Title/Summary/Keyword: Field capacity

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The Measurement of Soil Conditioning Effects of Organic Materials (유기물의 토양 개량 효과 측정)

  • 주영규
    • Asian Journal of Turfgrass Science
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    • v.7 no.1
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    • pp.13-18
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    • 1993
  • Much attention has been given recently to solve the environmental contamination in golf courses Changing to culture practice rather than chemical practice that depends on pesticides and fertilizers is a hot issue in golf courses or grasslands. Organic soil conditioners improve soil-plant envirormental conditions rich in physical properties. In this study, measuring systems to evaluate soil conditioning effects were set up for on-site purpose. After establishing the methodology for evaluating soil conditioner effects, 2 kinds of organic conditioners were rested for examination. The systems for the methodology included a set of simulating equipment for field capacity, an impact type soil column compactor, and an infiltration-percolation system. Test results using the systems showed bulk density and infiltration rate of mixed soil were decreased at highter rates of conditioner, but total porocities were increased. Increased porocities were most capillary pore space which has a positive effect on soil water potential. The systems and methodology in this study seem to have an efficiency to measure the effects of soil conditioner on site purpose.

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Comparison of Bearing Capacity Equations for Rock Socketed Drilled Shalt Based on the Results of Static Pile Load Test (정재하시험을 통해 산출되는 현장타설말뚝의 지지력이론식 비교연구)

  • 천병식;황성식;이승범
    • Proceedings of the Korean Geotechical Society Conference
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    • 2003.03a
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    • pp.333-340
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    • 2003
  • In Korea, drilled shaft are generally socketed into rock. Driven pile has environmental problems such as vibration and noise. Therefore, applications of the drilled shaft are increasing in Korea. In this paper, static load test data of the rock socketed drilled shaft at Gwangandaero and Suyeong 3hogyo are analyzed. The bearing capacities from field test data and theoretical formula are compared and analyzed. From this study, design approaches for drilled shafts in Korea are examined and several suggestions are proposed.

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Evaluation of Analysis Methodologies for Freeway Ramp Areas (고속도로 연결로 분석기법에 대한 평가)

  • 이정수;윤치환;김은연
    • Journal of Korean Society of Transportation
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    • v.10 no.1
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    • pp.5-20
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    • 1992
  • Even though the types of ramp facilities in Korea are not various like other countries operations in these sections are very important because ramp merging and /or diverging flow affects freeway overall sections. In this study existing methodologies especially the gap acceptance model and the regression model in USHCM are evaluated with our field data. By gap acceptance model the merging capacity is founded 2.360 pcph which is increased by 7% than the capacity of freeway basic section. And in comparison of actual lane 1 volume to the estimation volume by HCM model the model slightly overestimates the actual volue.

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Time-division hybrid WDM photonic switch architecture (시분할 하이브리드 WDM 광스위치 구조)

  • 김기태;엄진섭;김우찬;신서용;정홍식
    • Journal of the Korean Institute of Telematics and Electronics D
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    • v.34D no.5
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    • pp.52-60
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    • 1997
  • Photonic switching systems with throughput above Tbit/s are reuried to transport vast amounts of information for the coming B-ISDN. In this paper, we proposed a new time-division hybrid WDM photonic swithc architecture, the proposed basic switch module has simple configuratin consisted of frequency routers for wavelength division and cell coders and star couplers for time division. Through the comparison with other sysems in field of switching capacity, hardware complexity and cost effect of implemetnation, we proved that the proposed system is suitable for large-capacity photonic switching system.

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The Analysis of Optimum Locations of Rice Processing Complex (미곡종합처리장(米穀綜合處理場)의 적정입지분석(適正立地分析))

  • Chang, H.H.;Chang, D.I.;Kim, D.C.
    • Journal of Biosystems Engineering
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    • v.18 no.4
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    • pp.390-401
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    • 1993
  • This study was conducted to analyze the optimum capacity of Rice Processing Complex (RPC) and to select the optimum location of RPC based on the analysis of rice production and its commercializing rate for each county of major area of paddy field nationally. The study results showed that 500 of RPC having a drying capacity of 3,000 tons of rice would be needed nationally based on the selection analysis.

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말뚝기초의 연적 방향 극한하중

  • 김명모
    • Proceedings of the Korean Geotechical Society Conference
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    • 2002.11a
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    • pp.209-236
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    • 2002
  • Ultimate pile capacity - Point resistance - Frictional resistance - Determination of point and frictional resistances from field tests - Summary of recommendations from design Group effects Settlement analysis.

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The Four Power Plants Field Demonstration Research on Combustion Characteristic of the Bio Oil for Fuel Switching (국내 4개 중유발전소 실증실험을 통한 발전연료 대체용 바이오중유의 연소특성 연구)

  • Baek, Sehyun;Kim, Hyunhee;Park, Hoyoung;Kim, Young Joo;Kim, Tae Hyung;Ko, Sung Ho
    • Journal of the Korean Society of Combustion
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    • v.20 no.1
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    • pp.15-23
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    • 2015
  • This paper presents the results of field demonstration for fuel switching to bio-fuel oil in 4 commercial heavy oil fired power plants. The 100% fuel switching field demonstration was successfully carried out in two tangential-firing boilers at a capacity of 75 and 100 MWe respectively without major equipment retrofit, and also 25% bio-fuel oil blending for two opposite firing boilers at a capacity of 350 and 400 MWe respectively. Despite the low density and heating value, the bio fuel was successfully replaced heavy fuel oil at the full load by only adjusting operational parameters. Incase of bio fuel oil combustion, heat absorption of radiative heat transfer section was reduced while convection section has opposite trend. In pollutants emission, a major reductionin SOx as well as 10-20% reduction in NOx were achieved by the fuels witching. On the other hand, boiler efficiency was slightly underestimated.

Verification Studies for Field Peformance of Micropiling (성능검증을 위한 마이크로파일 현장 시험시공 및 재하시험)

  • Goo, Jeong-Min;Lee, Ki-Hwan;Cho, Young-Jun;Choi, Chang-Ho
    • Proceedings of the Korean Geotechical Society Conference
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    • 2009.03a
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    • pp.368-375
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    • 2009
  • This paper describes field installation and load test results performed for three types of micropiles in the process of developing a new micropiling method. Field tests were performed for two conventional types(i.e., micropile reinforced with steel bar and gravity grouting, micropile reinforced with steel bar and steel casing and gravity grouting) and a proposed type(i.e., micropile reinforced with hollow steel pipe wrapped with geotextile-pack and pressurized grouting). The load test results subjected to axial compression and tension and lateral loading conditions are described in this paper. The micropiles were exposed in the air in order to verify the installation quality and curing condition of grouting material via ground excavation. Axial compression and tension test results indicate that the new micropile type provide at least 40% higher bearing capacity than that of conventional types. Based on the examination of exposed piles, it is induced that the proposed method, packed micropile, provides better interlocking between grouts and surrounding soils and increases higher frictional resistance comparing to conventional types.

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Pullout Resistance Characteristics of the Wedge-shaped Soil Nail (쐐기형 쏘일 네일의 인발 거동 특성)

  • Kim, Bum-Joo;Lee, Yong-Jun;Yoon, Yong-Soo;Chung, Min-Kyu;Yoon, Ji-Nam
    • Proceedings of the Korean Geotechical Society Conference
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    • 2009.09a
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    • pp.1079-1083
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    • 2009
  • In this study, the pullout resistance characteristic of a wedge-shaped soil nail, made by attaching small steel sticks to the tip of a nail in a wedge shape, was investigated. It was developed to improve the overall pullout resistance capacity of the existing soil nail system, composed of nail and grout, by making the wedge provide additional pullout resistance. In order to evaluate the pullout resistance of the wedge shape-soil nail, field pullout tests were conducted, and the results were compared with those for the existing soil nail without the wedge. The field test results showed that the pullout resistance capacity of the wedge-shaped soil nail was 50% larger than that of the existing soil nail without the wedge.

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