• 제목/요약/키워드: fixing unit

검색결과 53건 처리시간 0.026초

유전자 알고리즘을 이용한 경지 구획 결정 지원 시스템 개발에 관한 연구 (A Study of Development of land use design system using GA for Agricultural area)

  • 정연철;윤성수;이정재
    • 한국농공학회:학술대회논문집
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    • 한국농공학회 2001년도 학술발표회 발표논문집
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    • pp.228-235
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    • 2001
  • For standard size of farmland in Korea is small, we have to consume huge labor for cultivation and efficiency of machine is low. We practice the project, which make size of farmland enlarge. For many factors have to consider in design process in case of large-scale farmland, there are difficulties for comparing alternatives if we design it manually. So we need to techniques for establishing various alternatives and choosing the optimum design by the computer. In this study, fixing the boundary of project using the RGIS (Rural Geographical Information System) which standard electronic map in Korea. In the boundary, we analysis the many characteristics of farm land, optimize the adjustment process of field unit of farmland. In this process, we develop automatic farmland division techniques. The results of adapting the developed system show the usefulness to enlarge the size of farmland about 200%.

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Marx 펄스발생기를 응용한 소형 고전압 급준 펄스 발생장치 (Fast Rise Time High Voltage Pulse Generator Applying The Marx Generator)

  • 박승록;정석환;김진규;문재덕
    • 대한전기학회논문지:전기물성ㆍ응용부문C
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    • 제50권2호
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    • pp.72-78
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    • 2001
  • A compact size high voltage pulse generator with nanosecond rise time has been designed and investigated experimentally. The inductance of a pulse generator can be reduced by fixing the Marx generator and pulse forming network components into a single cylindrical unit. As a result, nanosecond rise time about $8{\sim}10[ns]$ and pulse width of several hundred [ns] can be obtained from a modified Marx pulse generator. And parametric studies showed that the rise time of the output pulse was depended little on the change of the load resistance and the charging capacitance while, the pulse width of the output pulse was depended greatly upon the change of the load resistance and the charging capacitance. The theoretical showed the possibility to design the laboratory-size pulse generator very fast rising time and a proper pulse width by minimizing stray inductance and varying resistance and capacitance.

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Steering Wheel Torque Control of Electric Power Steering by PD-Control

  • Pang, Du-Yeol;Jang, Bong-Choon;Lee, Seong-Cheol
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2005년도 ICCAS
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    • pp.1366-1370
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    • 2005
  • As the development of microprocessor technology, electric power steering (EPS) system which uses an electric motor came to use a few years ago. It can solve the problems associated with hydraulic power steering. The motor only operates when steering assistance is needed, so it can save fuel and can reduce weight and cost by eliminating hydraulic pump and piping. As one of performance criteria of EPS systems, the transmissibility from road wheel load to steering wheel torque is considered in the paper. The transmissibility can be studied by fixing the steering wheel and calculating the torque needed to hold the steering wheel from road wheel load. A proportion-plus-derivative control is needed for EPS systems to generate desired static torque boost and avoid transmissibility of fluctuation. A pure proportion control can't satisfy both requirements.

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소형 나노초 입상 고전압 펄스발생장치 (Compact Size Nanosecond Rise Time Hgh Voltage Pulse Generator)

  • 박승록;문재덕
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1996년도 하계학술대회 논문집 C
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    • pp.1819-1821
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    • 1996
  • A compact size high voltage pulse generator with nanosecond rise time has been fabricated and investigated experimentally. It can be reduced the inductance of the generator by fixing the Marx generator components and pulse forming network components into a single cylindrical unit. As a result, it can be obtained nanosecond rise time about $8{\sim}10[ns]$ and pulse width of several hundred nanoseconds from the modified Marx pulse generator. And parametric studies showed that the rise time of the output pulse was depended little on the change of the load resister and the charging capacitor while the pulse width of the output pulse was depended greatly upon the change of the load resistor and the charging capacitor.

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Identification and Characterization of Bdellovibrio bacteriovorus, a Predator of Burkholderia glumae

  • Song, Wan-Yeob
    • Journal of Microbiology and Biotechnology
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    • 제14권1호
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    • pp.48-55
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    • 2004
  • Six strains of an obligate predatory bdellovibrio isolate that preys on Burkholderia glumae in rice paddy field water and rhizosphere soil, were identified and characterized. The numbers of Bdellovibrio cells varied from $3.2{\times}10^3$ to $9.2{\times}10^3$ plaque-forming unit/g after enrichment in cells of B. glumae. Prey range tests with six Bdellovibrio strains and 17 prey strains of rice-pathogenic, antibiosis-related, or nitrogen-fixing bacteria resulted in unique predation patterns in related prey cells. Strain BG282 had the widest prey range on 7 plant pathogenic bacteria among the 17 prey strains tested. However, no predation occurred with strains of Azospirillum brasilense, Paenibacillus polymyxa, Pseudomonas fluorescens, P. putida, and Serratia marcescens that are associated with antibiosis or nitrogen fixation in the rice ecosystem. Identification was confirmed by the presence of typical bdelloplast in the prey cells of B. glumae and by a PCR assay using B. bacteriovorus-specific primers. Furthermore, 16S rDNA sequencing of the six bdellovibrio strains showed a homology range of 97.2% to 99.2% to the type strain of B. bacteriovorus.

프로축구 승부조작 사건에 대한 프로축구연맹의 위기단계별 위기대응 커뮤니케이션 전략 분석 (Content Analysis of Crisis Response Communication Strategies along Crisis Stages for Match-fixing Case in K-League)

  • 방신웅;황선환
    • 한국콘텐츠학회논문지
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    • 제14권5호
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    • pp.390-402
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    • 2014
  • 본 연구는 Sturges의 위기단계 모델을 바탕으로 K리그 승부조작 사건에 대한 기사보도 빈도, 정보원 그리고 프로축구연맹의 위기대응 커뮤니케이션 전략을 분석하였다. 언론에 보도된 118개의 K리그 승부조작 관련 기사를 대상으로 빈도분석, 내용분석을 실시하였다. 위기단계별 위기대응 커뮤니케이션 전략의 분석단위는 문장단위로 분석하였다. 분석결과 위기단계별 언론보도의 빈도는 위기발생단계에서 가장 높게 나타났다. 보도내용에 대한 정보원은 프로축구연맹, 대한축구협회, 구단, 감독, 선수, 문화체육관광부, 검찰, 전직선수 및 감독, 축구전문가 등 다양한 정보원이 활용되었으며, 이들 중 프로축구연맹이 모든 위기단계에 걸쳐 가장 높은 인용빈도를 보였다. 프로축구연맹의 위기대응 커뮤니케이션 전략은 전체적으로 재발방지를 위한 조치를 취하는 개선행위 전략을 가장 많이 구사한 것으로 나타났다. 구체적으로 위기발생단계에서는 팬들에게 사과하고 재발방지를 약속하는 개선행위 전략을 구사하였으나 변명, 책임전가 등, 대응전략의 일관성을 해치는 전략이 동시에 사용되기도 하였다. 반면에 만성적위기단계와 위기종결단계에서는 재발방지대책과 사건에 연루된 선수들에 대한 징계조치를 취하는 개선행위전략이 일관성 있게 나타났다. 한편, 구단과 선수의 위기대응 커뮤니케이션 전략은 프로축구연맹의 위기대응 커뮤니케이션 전략과 일관성이 없는 것으로 나타났다. 이러한 연구결과에 대한 시사점과 향후연구 방향을 제시하였다.

개방적 가설검증 학습모형을 적용한 과학 탐구학습의 효과:화학 I ‘금속과 그 이용’ 단원을 중심으로 (The Effects of Science Inquiry Learning Applying Open- Ended Hypothesis-Testing Learning Model: On the ‘Metals and Their Applications’ Unit in Chemistry)

  • 정대홍;방정아;최취임;최원호
    • 대한화학회지
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    • 제50권5호
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    • pp.385-393
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    • 2006
  • 연구에서는 고등학교 화학 수업에서 개방적 가설검증 학습모형을 적용한 과학 탐구학습을 실시하고, 학생들의 인지 수준에 따른 과학 탐구능력, 과학 수업에 대한 태도에 미치는 효과와 수업에 대한 인식을 알아보았다. 서울에 소재한 남자 고등학교 2학년 4개 학급의 학생들(92명)을 대상으로 개방적 가설검증 학습모형을 적용한 과학 탐구학습을 실시한 처치집단과 실험과정이 모두 제시된 실험 수업을 실시한 통제집단으로 배치한 후, 화학의 ‘금속과 그 이용' 단원에 대해서 수업을 실시하였다. 연구 결과에 의하면, 개방적 가설검증 학습모형을 적용한 과학 탐구학습은 과학 탐구능력 향상에 관해서 실험설계, 자료 변환 및 해석, 가설검증의 영역에서 유의미한 효과가 있었으며 문제 파악 및 정의, 가설설정의 영역에서는 효과가 없었다. 한편, 개방적 과학 탐구학습에서 학생들의 역할 및 수행할 과제의 증가로 인해 과학 수업에 대한 태도는 처치집단에 부정적인 효과가 나타났다.

중학교 기술 가정.교과서의 의복구성 분야 내용 분석 (The Content Analysis of Clothing Construction field in the middle-school Textbook of Technology and Home Economics)

  • 박은희;조현주
    • 패션비즈니스
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    • 제17권1호
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    • pp.131-144
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    • 2013
  • The purpose of this study was to analyse the structure and contents of clothing construction field in the middle-school textbook of technology and home economics with curriculum revised in 2007. 10 kinds of textbooks certified by Ministry of Education, Science and Technology in 2010 were selected and home economics field in them was the subject of this study with the external characteristics such as textbook system, instruction area and contents included. This study was content analysis-oriented and descriptive with data calculated by frequency and percentage. The findings are as follows. In 'Reality of Home-Life', food life area showed highest as 34.4% followed by clothing life(28.7%) and dwelling life(28.7%). The portion of present teachers in writing staffs was highest while there was no textbook where professors of each field were included in writing staffs. The contents of costume society, clothes material, clothes management from section 'Choice and Management of Clothes' in the chapter 'Family Life' and clothing construction from the section 'Making and Modifying Clothes' of the chapter 'Reality of Home-Life' were analysed in this study. Clothing construction-related fields were suggested separately by method of measurement, construction theory, drafting theory, drafting an original form, fabric trimming, utilization of the original form, length measure, cloth cutting, hand stitching, how to use a sewing machine, basting and correction, needlework process, completion, and evaluation. The contents of the unit 'Making Shorts' were about clothing construction theory, human body measurement, drafting an original form, process of making shorts and activity/research/experience. The contents of the unit 'Wearing Clothes after Fixing' in clothing construction-related field were about how to fix and recycling.

대형선박의 액체 탱크용 수위 모니터링 센서 시스템 연구 (A Study on the Tank Liquid-Level Monitoring Sensor Systems for Large Scaled Vessels)

  • 손경락;김진욱;조석제;심준환
    • Journal of Advanced Marine Engineering and Technology
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    • 제33권2호
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    • pp.330-335
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    • 2009
  • A fiber-optic liquid level sensor based on bending cantilever beam has been proposed. A fiber Bragg grating(FBG) embedded in the cantilever beam is used to sensing elements. The basic concept is elongation and constriction of the FBG corresponding to the liquid level variation. The best FBG position on the cantilever for obtaining the high sensitivity was 4 cm from the fixing point. When the liquid level moves up and down vertically, the Bragg wavelength is linearly shifted. But, the wavelength sensitivity of the FBG installed on the upper side of cantilever was four times better than that of the FBG equipped in the lateral side due to the difference of unit strain applied to the FBG. Intensity demodulation using the low-cost edge filter is used to interrogate the Bragg wavelength through converting the wavelength signals into the optical intensity ones. Experiment results show that the electrical output is exponentially proportional to the liquid level. But, it should be overcome for applying to the ships.

사출성형 특성을 고려한 2인치 휴대폰용 도광판 금형제작에 관한 연구 (Effects on the process factors of blow molding affects to the PET bottle)

  • 황철진;도영수;김종선;민인기;김종덕;윤경환
    • Design & Manufacturing
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    • 제2권6호
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    • pp.1-6
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    • 2008
  • Recently, many researches have been done to improve optical performance of LCD-BLU(Back Light Unit). One of the most important parts in LCD-BLU is LGP(Light Guiding Plate). Micro-patterned LGP is known to have different optical characteristics depending on their shape, pattern density and size, etc. In the present study, a micro-optical patterned LGP mold was fabricated using LiGA process. The difference in the optical characteristics between positive and negative patterned LGP's was investigated by fixing the density, location and size of each pattern. It was found that the negative patterned LGP showed better optical characteristics than positive one.

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