• 제목/요약/키워드: operation principle

검색결과 896건 처리시간 0.036초

초등수학에서 직관적 원리에 의한 교육 내용 분석 (An Analysis on the Instructional Contents by Intuitive Principles in Elementary Mathematics)

  • 이대현
    • 한국초등수학교육학회지
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    • 제15권2호
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    • pp.283-300
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    • 2011
  • 이 연구는 초등학교 수학 지도에서 직관적 원리의 중요성을 인식하고, 교육과정과 그 해설서, 그리고 교과서에 제시된 직관적 원리에 의한 교육 내용을 분석하였다. 이를 위해 초등학교 교육과정과 그 해설서에 제시된 교육 내용에서 직관적 원리에 의한 내용을 추출하고, 이 내용이 교과서에 어떻게 구현되었는가를 분석하였다. 분석결과, 교육과정의 수학 교과의 성격에서는 직관적 원리에 의한 지도를 제시하고 있었으나, 목표와 학습 방법, 평가에서는 직관적 원리에 의한 지도 내용을 제시하지 않고 있었다 또한 내용영역에서는 교육과정 문서에는 직관적 원리에 의한 지도 내용을 제시하지 않았고, 교육과정 해설서에만 도형 영역 12개, 측정 영역 1개, 확률과 통계영역 2개가 제시되어 있었다. 그리고 본 연구에서 제시한 직관적 지도 원리 6가지 중에서 특정 원리에 치중되어 있었다. 이러한 결과를 바탕으로 교육과정 구안과 교과서 집필에 필요한 직관적 원리에 따른 수학 지도의 시사점을 도출하였다.

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신용장상 서류비지정조건의 취급에 관한 소고 (A Study on Non-documentary Condition in L/C Transactions)

  • 김기선;김영훈
    • 무역상무연구
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    • 제42권
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    • pp.109-132
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    • 2009
  • The purpose of the introduction of this article is as follows. It was frequent to put a condition on the letter of credit without stating corresponding document. But these attempts are very dangerous to the letter of credit operation. That is, if these types of conditions would be permitted in letter of credit, the independence principle must be collapsed. So these conditions must be disregarded in order to safeguard the independence principle. It is why UCP600 article 14(h) writes that if a Credit contains a condition without stating the document(s) to be presented in compliance therewith, banks will deem such conditions as not stated and will disregard it. But scope of this article 14 should not be limited by the conditions which do not state the document to be presented in compliance therewith. That is, the purpose of this article is to preserve the independence principle, so, if it is impossible to ascertain satisfaction with a condition, it should be disregarded as the non-documentary condition, even if the condition is included in the letter of credit together with document to be presented. Conclusively, whether or not a condition would be regarded as the non documentary condition depends on whether compliance of such condition is ascertained by presented documents stipulated in the letter of credit.

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High-accuracy quantitative principle of a new compact digital PCR equipment: Lab On An Array

  • Lee, Haeun;Lee, Cherl-Joon;Kim, Dong Hee;Cho, Chun-Sung;Shin, Wonseok;Han, Kyudong
    • Genomics & Informatics
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    • 제19권3호
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    • pp.34.1-34.6
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    • 2021
  • Digital PCR (dPCR) is the third-generation PCR that enables real-time absolute quantification without reference materials. Recently, global diagnosis companies have developed new dPCR equipment. In line with the development, the Lab On An Array (LOAA) dPCR analyzer (Optolane) was launched last year. The LOAA dPCR is a semiconductor chip-based separation PCR type equipment. The LOAA dPCR includes Micro Electro Mechanical System that can be injected by partitioning the target gene into 56 to 20,000 wells. The amount of target gene per wells is digitized to 0 or 1 as the number of well gradually increases to 20,000 wells because its principle follows Poisson distribution, which allows the LOAA dPCR to perform precise absolute quantification. LOAA determined region of interest first prior to dPCR operation. To exclude invalid wells for the quantification, the LOAA dPCR has applied various filtering methods using brightness, slope, baseline, and noise filters. As the coronavirus disease 2019 has now spread around the world, needs for diagnostic equipment of point of care testing (POCT) are increasing. The LOAA dPCR is expected to be suitable for POCT diagnosis due to its compact size and high accuracy. Here, we describe the quantitative principle of the LOAA dPCR and suggest that it can be applied to various fields.

기준전류추정형 인버어터에 의한 2 권선전동기의 2 상운전특성 (Characteristics of Two Phase Operation of Two Winding Motor Driven by Reference Current Adaptive Inverter)

  • 원종수;정의상
    • 대한전기학회논문지
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    • 제33권8호
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    • pp.289-298
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    • 1984
  • The single phase induction motor is recently requested to meet a broad speed control and smooth forward and reverse operation due to the multifarious usages. This paper deals with two phase operation of a two winding motor by reference current adaptive inverter which can supply the currents to satisfy the balanced oeration into the main and auxiliary winding through the entire operational region. According to the roposed system, the starting, forward and reverse and variable speed control of a two winding motor eliminated the capacitor from the capacitor-run motor is also possible. The formation and its principle of the reference current adaptive inverter and characteristic analysis of the motor fed by this apparatus are described in this paper. Excellent agreement with the measured results and calculated values by computer simulation is obtained.

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연속효소반응장치의 최적반응조작설계 (Optimal Operation Design of Continuous Enzymatic Reactor System)

  • Namkoong, Shik
    • 한국미생물·생명공학회지
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    • 제2권2호
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    • pp.63-77
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    • 1974
  • 가장 복잡한 반응기구를 갖은 효소반응의 예로서, 생성물에 의한 비길항 및 길항 2중조해를 입는 효소반응의 경우에 대하여 연속효소반응장치의 반응 조작을 Pontryagin의 연속형최대원리에 의하여 연구하여 얻은 최적설계법을 보고하였다. 설계예로서 유두영 등의 보문에 발표된 반응속도에 관한 data를 사용하여 합성 Penicilline의 중간체인 6-APA 합성반응공정의 경우를 다루었다.

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비대칭 고장전류 저감을 위한 재폐로 차단기 제어 방안 (A Control Scheme of Recloser for Asymmetrical Fault Current Reduction)

  • 이상봉;김철환;서훈철;고윤태;김규호;김재철;현옥배
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2009년도 제40회 하계학술대회
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    • pp.215_216
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    • 2009
  • This paper presents a asymmetry fault current reduction scheme with recloser operation during transient period. The principle of asymmetry current nature is reviewed and asymmetry components reduction with recloser operation is explained. Throughout the simulation, results verifies the proposed scheme for recloser operation and its effectiveness.

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비대칭 고장전류에 따른 초전도 한류기 동작 분석 (An Analysis of Superconducting Fault Current Limiter Operation According to Asymmetry Fault Current)

  • 이상봉;김철환;김규호;김재철;현옥배
    • 전기학회논문지
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    • 제58권3호
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    • pp.450-454
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    • 2009
  • This paper analyzes a asymmetry current with SFCL (Superconducting Fault Current Limiter) operation during transient period, when a fault occurs in power systems. The principle of asymmetry current nature is reviewed and asymmetry components reduction with SFCL operation is explained. To verify the performance of SFCL, a EMTP/ATPDraw model of SFCLs using MODELS language developed and simulated. Throughout the simulation, results presents the main factors for reducing the asymmetry component of fault current are not a quenching time, but a limiting resistance of SFCL and fault initiated angle.

전기기구의 운전에 의하여 발생되는 자계의 측정 (Measurement of Magnetic Field Generated by the Operations of Electric Appliance)

  • 이복희;길경석;박형기
    • 대한전기학회논문지
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    • 제43권6호
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    • pp.1001-1009
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    • 1994
  • The present paper deals with a new developed sensor for measuring the time-varying magnetic fields and describes the experimental results of trasient magnetic field that takes place during the operations of electric appliance. The operation principle of the self-integrating magnetic field sensor by using coaxial cable is analyzed and a calibration investigation is carried out. The frequency bandwidth of the magnetic field measurement system is from 40 Hz to about 300 kHz. The magnetic field induced by the starting and/or operation of electric appliance mainly includes the odd harmonics such as the third, the fifth and the seventh harmonics. The magnetic field intensity caused during the operation of ultrasonic washer is inversely proportional to distance, this correspodns to induction component. As a result, it was known that the odd harmonics of magnetic field in the desing of electromagnetic shield employed for protecting electronic circuit and control devices have to be considered.

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배전계통에 있어서 열병합 분산형전원의 최적 도입계획에 관한 기초적 연구 (Optimal Planning for Dispersed Generating Sources in Distribution Systems)

  • 심헌;노대석;최재석
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2000년도 하계학술대회 논문집 A
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    • pp.513-515
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    • 2000
  • This paper deals with a method for determining an optimal operation strategy of dispersed generating sources considering thermal merits. The optimal operation of these sources can be determined by the principle of equal incremental fuel cost. This paper presents an optimal operation strategy using the Kuhn-Tucker's optimal conditions and also an priority method to decide the optimal location of those sources in power systems. The validity of the proposed algorithms are demonstrated using a model system.

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에너지 저장 시스템을 위한 비절연 양방향 ZVT DC-DC 컨버터 (Nonisolated Bidirectional ZVT DC-DC Converter for an Energy Storage System)

  • 한기태;임창순;김래영;현동석
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2012년도 추계학술대회 논문집
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    • pp.50-51
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    • 2012
  • The paper presents a non-isolated bidirectional DC-DC converter for use in renewable power generation, battery, electric vehicles (EV) and small scale DC-UPS systems. In the propose design, the conventional interleaved operation of two-inductor boost structure is modified to accommodate bidirectional operation, and zero-voltage-transition (ZVT) is applied, where both the switch and the rectifier diode achieve soft condition without increasing their voltage and current stresses. The proposed converter has the merits of simple circuitry, reduced size, low cost and high efficiency. The operation principle of the converter is analyzed and verified. Also, simulation results of the proposed bidirectional dc-dc converter is shown.

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