• 제목/요약/키워드: complete fields

검색결과 231건 처리시간 0.026초

GPS를 이용한 축분퇴비의 농지환원 실태조사 (GPS Application in Investigating Land Application of Animal Waste)

  • 홍성구
    • 농촌계획
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    • 제7권2호
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    • pp.3-11
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    • 2001
  • A portable GPS receiver and a navigation software were used to investigate land application practices of manure composts. The field investigation indicated that most of the land application of manure composts were observed before April. Plowing for incorporation of manure with soil were continued from the middle of April. The results also revealed that over 60% of the farms were within 1 km from livestock farms from which manure composts were transported. Most of the farms having land application were dry field rather than paddies, Some of fields located near livestock farms frequently experience over-application of manure composts. It seems to have been difficult to complete the investigation in this study without the Gps/navigation system. The GPS/navigation system will become an essential tool in field investigations such as ecological/environmental monitoring works that require repeated observation at a number of sites.

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Closed-form Green's functions for transversely isotropic bi-solids with a slipping interface

  • Yue, Zhong Qi
    • Structural Engineering and Mechanics
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    • 제4권5호
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    • pp.469-484
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    • 1996
  • Green's functions are obtained in exact closed-forms for the elastic fields in bi-material elastic solids with slipping interface and differing transversely isotropic properties induced by concentrated point and ring force vectors. For the concentrated point force vector, the Green functions are expressed in terms of elementary harmonic functions. For the concentrated ring force vector, the Green functions are expressed in terms of the complete elliptic integral. Numerical results are presented to illustrate the effect of anisotropic bi-material properties on the transmission of normal contact stress and the discontinuity of lateral displacements at the slipping interface. The closed-form Green's functions are systematically presented in matrix forms which can be easily implemented in numerical schemes such as boundary element methods to solve elastic problems in computational mechanics.

Numerical Analysis on Pressure Characteristics of the Pipe system of Train

  • 남성원;장파
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2004년도 추계학술대회 논문집
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    • pp.503-509
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    • 2004
  • With modem computational fluid dynamics method (CFD), air-charging models of the air brake pipe system and auxiliary reservoir are built. Compared with one-dimension model, no empirical formula is introduced to solve branch pipe fields for two-dimension model. A modified operator-splitting method is presented to solve the coupled equations of pressure and velocity, and numerical simulation shows that it is very stable. Compare the numerical results with empirical data of heavy haul trains in home and abroad so as to prove the correctness of the theory and algorithm presented. This paper gives theoretic reference to the experiments of braking effects of heavy haul trains, and forms a basis for development of complete freight train air brake system simulation.

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소형궤도 차량용 유도전력급전 계통 모델링 (The modeling of the IPT system used for PRT (Personal Rapid Transmit))

  • 이병송;배창한;변윤섭;한경희
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2004년도 추계학술대회 논문집
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    • pp.1413-1418
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    • 2004
  • This paper shows the analysis of the inductive power transfer system in conjunction with series resonant converter operating variable high frequency. Of particular interest is the sensitivity of the complete system to variations in operational frequency and parameters. In inductive power transfer system, electrical power is transferred from a primary winding in the form of a coil or track, to one or more isolated pick-up coils that may relative to the primary. The ability to transmit power without contact enables high reliability and easy maintenance that allows inductive power transfer system to be implemented in hostile environments. This technology has found application in many fields such as electric vehicles, PRT(Personal Rapid Transit) etc. The coupling between the primary and secondary is then presented to include the effects of parameter and operational frequency variation.

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ALMOST SURE MARCINKIEWICZ TYPE RESULT FOR THE ASYMPTOTICALLY NEGATIVELY DEPENDENT RANDOM FIELDS

  • Kim, Hyun-Chull
    • 호남수학학술지
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    • 제31권4호
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    • pp.505-513
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    • 2009
  • Let {$X_k;k{\in}N^d$} be centered and identically distributed random field which is asymptotically negative dependent in a certain case. In this note we prove that for $p{\alpha}$ > 1 and ${\alpha}$ > ${\frac{1}{2}}$ $E{\mid}X_1{\mid}^p(log^+{\mid}X_1{\mid}^{d-1})$ < ${\infty}$ if and only if ${\sum}_n{\mid}n{\mid}^{p{\alpha}-2}P$($max_{1{\leq}k{\leq}n{\mid}S_k{\mid}}$ > ${\epsilon}{\mid}n{\mid}$) < ${\infty}$ for all ${\epsilon}$ > 0, where log$^+$x = max{1,log x}.

소형궤도차량 유도전력급전 계통 특성해석 (The Characteristic analysis of the IPT system used for PRT(Personal Rapid Transmit))

  • 이병송;김도원;한경희
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2005년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
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    • pp.218-220
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    • 2005
  • This paper shows the analysis of the inductive power transfer system in conjunction with series resonant converter operating variable high frequency. Of particular interest is the sensitivity of the complete system to variations in operational frequency and parameters. In inductive power transfer system, electrical power is transferred from a prima교 winding in the form of a coil or track, to one or more isolated pick-up coils that may relative to the primary. The ability to transmit power without contact enables high reliability and easy maintenance that allows inductive power transfer system to be implemented in hostile environments. This technology has found application in many fields such as electric vehicles, PRT(Personal Rapid Transit) etc. The coupling between the primary and secondary is then presented to include the effects of parameter and operational frequency variation.

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용융금속 미립화에 관한 기초적 연구 (A Fundamental Study on the Gas Atomization of Liquid Metal)

  • 강민성;최종윤;김희동
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2008년도 추계학술대회B
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    • pp.2777-2781
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    • 2008
  • Gas atomization of liquid metal using nozzle technology has more advantages over other methods. Previous study shows that high-velocity gas is important for effective liquid metal atomization. An important first step towards understanding the gas atomization using nozzle is complete evaluation of the flow fields. This will provide a basis for understanding how well high velocity gas is brought to bear on the liquid metal. Present work is a fundamental study of liquid metal atomization for various pressure ratio, different gas and temperature. A two-dimension, axisymmetry compressible Navier-Stokes equations are considered. Two-equation k-epsilon turbulence model is selected.

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Application of BIM on Drawing Verification of Firefighting

  • Chang, Ya-Chun;Shr, Jin-Fang;Huang, Xuan-Chao
    • International Journal of Aerospace System Engineering
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    • 제2권2호
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    • pp.15-18
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    • 2015
  • In general, most of the function and using of building is for single purpose. However, current buildings combine several functions that causes a lot of problems not on firefighting only but also on environment engineering. Because of hard integration on different fields that causes a lot of conflict. That wastes cost and time. That also threaten the safety of firefighting. This search focuses on the drawing verification and field inspection on firefighting. These two items both remain paper work. To complete the current work, it needs to bring a great amount of drawing papers in the field. By BIM, integrated data can be extracted. It makes the drawing verification and field inspection easier and increases the efficiency. That is the main point of this research.

공공데이터 개방 평가지표 개발을 통한 현황분석 및 가시화 (Service Level Evaluation Through Measurement Indicators for Public Open Data)

  • 김지혜;조상우;이경희;조완섭
    • 한국빅데이터학회지
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    • 제1권1호
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    • pp.53-60
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    • 2016
  • 공공데이터 포털에 공개된 지자체 데이터와 공공기관 데이터를 자동으로 수집한 후, 공공 데이터의 개방현황 및 다양한 영역별 데이터 제공여부, 파일 형식 등 다양한 기준으로 다차원 분석하여 서비스 수준 평가를 제공하고자 한다. 이를 위해, 해외 평가지표 사례를 바탕으로 평가지표 내용을 설정한 후 이를 기준으로 데이터웨어하우스(DW)를 구축하였으며, 다차원 분석 기법을 사용한 서비스 수준평가 결과를 지역별로, 기관별로, 분야별로 시각화한다.

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Development of Reliability Engineering in China

  • Zhang, Zengzhao;Pang, Fuli
    • 한국신뢰성학회:학술대회논문집
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    • 한국신뢰성학회 2006년도 학술발표대회 논문집
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    • pp.3-19
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    • 2006
  • The Status quo of the reliability in China is described in this paper, a reliability surge is now spreading in China, covering the fields such as hardware, software, machinery and electronics. The reliability work in China was firstly conducted by the CEPREI Lab as far as early in the 1950s, and the reliability engineering in China has developed from the reliability of electronic products to that of machinery and non-electronic products, from hardware reliability to software reliability, from the attention to the reliability statistical test to emphasis on the reliability engineering test. Concern of Chinese companies about the reliability is the complete import of reliability engineering, the reliability testing, the software reliability and the reliability of lead-free soldering. Demonstration of reliability cases is given.

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