• Title/Summary/Keyword: the field

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Factors Influencing on the Field Education Outcome on Time-registration Student (시간제 등록 학생의 사회복지현장 실습성과에 영향을 미치는 요인)

  • Lee, Hyoung-Ha
    • The Journal of the Korea Contents Association
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    • v.9 no.9
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    • pp.226-234
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    • 2009
  • This study aims to research the influencing factors of field education outcome. This study is to help the social welfare subject find out the field education orientation. Following is the result brought out from the research. First, it was found that the evaluation of field manager, field agency and field education outcome working in social welfare agencies had no meaningful statistical difference. Second, the results of regression analysis showed that the evaluation of field manager and field agency had influenced on field education outcome. Along with major of the study, implications for expanding opportunities of continuing educations for managers in non-profit organization are discussed.

An Experimental Study on the Effect of Electric Field the Ornithine Decarboxylase Activity Change of Myeloid Cells According to Ionizing Radiation Exposure (이온화방사선 피폭에 의한 골수세포의 Ornithine Decarboxylase 활성도의 변화에 대한 전계장의 영향에 관한 실험적 연구)

  • 정문호
    • Journal of Environmental Health Sciences
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    • v.21 no.1
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    • pp.78-85
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    • 1995
  • Ornithine decarboxylase(ODC) is an indicate enzyme in carcinogenesis. We divided Sprague Dawley rats into six groups: control, electric field exposure, X-ray only irradiation, X-ray irradiation with electric field exposure group, Sr-90 injected group and Sr-90 and electric field complex exposure group. The ODC activity was measured in rat's bone marrow cell every week. The results were summarized as follows: The ODC activitied was increased in X-ray irradiated, Sr-90 injected and Sr-90 and electric field complex exposed group as compared with that of control(p<0.05). The ODC activity was increased comparing that of control neither in X-ray and electric field complex exposed group nor electric field only exposed group. This result suggests that the electric field doesn't have myeloid carcinogenicity and myeloid cancer incidence caused by ionized radiation is suppressed by electric field exposure.

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Thermo-Field emission in silicon nanomembrane ion detector for mass spectrometry (실리콘 나노 박막의 열-전계 방출효과를 이용한 분자 질량분석)

  • Park, Jong-Hoo
    • Journal of the Korean Applied Science and Technology
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    • v.30 no.4
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    • pp.586-591
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    • 2013
  • This paper describes the characteristics of thermo-field emission in a freestanding silicon nanomembrane under ion bombardment with various thermal and field conditions. The thermal effect and field effect in thermo-field emission in silicon nanomembrane are investigated by varying kinetic energy of ions and electric field applied to the silicon nanomembrane surface, respectively. We found that thermo-field emission increases linearly as the electric field increases, when the electric field intensity is lower than the threshold. The thermo-field emission (schottky effect) increases proportionally to the power of temperature, which agree well with the predictions of a thermo-field emission model.

A Method and System to Compensate Vertical Component of 3-Dimensional Magnetic Field Sensor Using The Earth's Field (지구자계를 이용한 3축 자계센서의 수직성분자계 보정방법 및 장치)

  • Jung Young-Yoon;Lim Dae-Young;Ryoo Young-Jae
    • Journal of the Korean Institute of Intelligent Systems
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    • v.16 no.3
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    • pp.297-302
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    • 2006
  • In this paper, a method and system to compensate vertical component of 3-dimensional magnetic field sensor using the earth's field was described. Output of magnetic field sensor have a output offset that is generated setting angle error of magnetic sensor and gain error. Thus, to using the magnetic field sensor, it must be compensated. The compensation of magnetic field sensor is required at shield space. However, using the earth's field, output offset of the sensor can be simply compensated. And, we designed system for compensation of the sensor. The proposed method and system are verified usefulness through experimental.

Optimal Design of Field Ring for Power Devices (고 내압 전력 소자 설계를 위한 필드 링 최적화에 관한 연구)

  • Kang, Ey-Goo
    • Journal of IKEEE
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    • v.14 no.3
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    • pp.199-204
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    • 2010
  • In this paper, we proposed trench field ring for breakdown voltage of power devices. The proposed trench field ring was improved 10% efficiency comparing with conventional field ring. we analyzed five parameters of trench field ring for design of trench field ring and carried out 2-D devices simulation and process simulations. That is, we analyzed number of field ring, juction depth, distance of field rings, trench width, doping profield. The proposed trench field ring was better to more 1000V.

FIELD MAPPING FOR PADDY RICE

  • Lee, C-K.;M. Umeda;M. Iida;J. Yanai;T. Kosaki
    • Proceedings of the Korean Society for Agricultural Machinery Conference
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    • 2000.11b
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    • pp.254-261
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    • 2000
  • Soil chemical properties, relief of field surface, SPAD values and grain yield were investigated in a 0.5ha paddy field in 1999 to obtain basic field information for precision agriculture. Descriptive statistics of field information showed that the coefficient of variation ranged from 1.63% to 38.7%. Field information showed a high spatial dependence for within paddy field. The ranges of spatial dependence were from 15m to 60m, respectively. Kriged maps enable the visualization and comparison the spatial variability of field information. The causes of spatial variability of the field information could be explained rationally by a field management map. Grain yield was negatively correlated with pH, relief values, whereas, was positively correlated with total C, total N, C/N ratio, mineralizable N, available P and exchangeable K, Ca at the significant level of 1 %.

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A study on Field-Weakening Control for Permanent Magnet Synchronous Motor (영구자석형 동기전동기의 약계자제어에 관한 연구)

  • Lee, Cheol-Gyun;Won, Jong-Soo
    • Proceedings of the KIEE Conference
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    • 1990.11a
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    • pp.5-9
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    • 1990
  • A permanent magnet synchronous motor(PMSM) differs from an ordinary synchronous motor in that the former has no field winding and the field flux can not be controlled by field current. A field-weakening control of PMSM utilizing the demagnetization due to d-axis armature reaction is equivalent to reducing the field current. In this paper, the armature resistance is considered for the optimum field-weakening control.

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Study on The Preventive Structure of field Lead Connector's V-Notch on Synchronic (동기발전기 회전자 계자접속부의 예각변형 방지구조에 관한 연구)

  • Cho, Ji-Won;Cho, Chang-Joo
    • Proceedings of the KIEE Conference
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    • 2000.07b
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    • pp.937-939
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    • 2000
  • The preventive structure of field lead connector's V-notch on synchronous generator has been developed. The preventive structure of field lead, installed in the generator, prevent from V notch of field lead connector in rotor on daily start and stop (on-line). This development of study was performed at the Seoinchon combined cycle power plant on gas turbine generator. This preventive structure of field lead will be prevent from V-notch of field lead on synchronous generator's field.

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Properties of Field Emission Electrons for CVD-grown Carbon Nanotubes (CVD법으로 제조한 탄소 나노튜브의 전계 전자 방출 특성)

  • Lee, Rhim-Youl
    • Korean Journal of Materials Research
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    • v.13 no.7
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    • pp.424-428
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    • 2003
  • The microstructure and field emission properties of carbon nanotubes(CNT) grown by Ni-catalytic chemical vapor deposition(CVD) were investigated. CVD-grown CNT had a high density of curved shape with randomly oriented. It was found that an increase in electric field caused an increase in field emission current and field emission sites of CNT. The maximum field emission current density was measured to be 3.6 ㎃/$\textrm{cm}^2$ at 2.5 V/$\mu\textrm{m}$, while the brightness of 56 cd/$\textrm{cm}^2$ was observed for the CNT-grown area of 0.8 $\textrm{cm}^2$ from a phosphor screen. Field emission current at constant electric field gradually decreased initially and then stabilized with time.

A removal characteristics of NOx at the cylinderical plasma reactor with magnetic field (자계가 인가된 원통형 플라즈마 반응기에서 질소산화물(NOx)의 제거특성)

  • Lee, Dong-Hoon;Lee, Tae-Geun;Oh, Jung-Min;Lee, Doo-Hee
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2004.05b
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    • pp.104-108
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    • 2004
  • The effect of magnetic field was measured on NOx removal for cylinder-wire plasma reactor with magnetic field applied to electric field vertically. Power was supplied to plasma reactor using rotating spark gap switch. Consumption power increased with increasing discharge voltage. When magnetic field was applied to electric field vertically, consumption power was less than that without magnetic field because of lorenz's force. NOx removal rate of plasma reactor with magnetic field were higher, 10-15%, than that of plsama reactor without magnetic field. And NOx removal rate decreased with increasing gas flow rate.

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