• 제목/요약/키워드: Level number

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단상 Multi-Level AC-DC 컨버터 (Single Phase Multi-Level AC-DC Converter)

  • 안일매;전중함;이영호;박성우;서기영;이현우
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 1999년도 전력전자학술대회 논문집
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    • pp.354-357
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    • 1999
  • This paper is proposed Single phase Multi-Level AC-DC Converter. This is consist of diode bridge and switches. The number of the supply current levels depends on the number of the individual converter's current level. In this converter circuit the number of the levels is equal to 2(M+1) -1, where M is the number of Switching-Leg's number. In this paper is introduced converter with 31 current Level. If the number of current level is increased, smoother sinusoidal waveform can be obtained. The feasibility of the circuit is verified by computer simulation using PSIM

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a- Si:H TFT Level Shifter with Reduced Number of Power

  • Jeong, Nam-Hyun;Chun, Young-Tea;Kim, Jung-Woo;Bae, Byung-Seong
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2008년도 International Meeting on Information Display
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    • pp.20-23
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    • 2008
  • We proposed a-Si:H TFT (hydrogenated amorphous silicon thin film transistor) level shifter which reduced number of power sources. To reduce the number of power sources from four to two, modified bootstrapped inverter was used for the level shifter. The shift register was verified by PSPICE circuit simulation and fabricated. The fabricated level shifter successfully shifted low input (0 to 5 V) to high level output (-7 to 23 V).

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한국유아의 수단어 획득에 관한 연구 (The Acquisition of Korean Number-Word Systems of Young Children)

  • 홍혜경
    • 아동학회지
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    • 제11권2호
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    • pp.5-23
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    • 1990
  • The purpose of this study was to investigate the acquisition of number-word systems of young children. Specifically, the acquisition of Korean Number-Words(KNW) was compared with the acquisition of Chinese-derived Number-Words(CNW). The subjects included 120 children aged 2:5 to 5:11. The subjects oral counting using the two number word systems were audiotaped. Two coders transcribed the tapes. The data were analyzed by content analysis with descriptive statistics. The findings of this study showed that the acquisition of KNW began from around age two and the acquisition of CNW from around age three. From then, the acquisition of the two number-word systems was parallel. The acquisition of number-words began from the age of 2 years, increased slowly to the age of 4. and then increased rapidly after the age of 5. Although KNW were acquired earlier than CNW, at around the age of 5 years the acquisition of CNW surpassed the acquisition of KNW. The acquisition of number words consists of four developmental levels: Level I: beginning of acquisition of traditional KNW only Level II: beginning of acquisition of CNW with extension of KNW Level III: parallel extension of the two number-word systems Level IV: superior acquisition of CNW. The major error through all stages in the sequence of number words was the omission of one number-word. Younger children produced errors of omission of one, two or three number-words, whereas older children produced errors of nonstandard number-words and repetition.

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Multi-Level Skip-Lot Sampling Plan

  • Cho, Gyo-Young;Ahn, Young-Sun
    • Communications for Statistical Applications and Methods
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    • 제8권2호
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    • pp.383-394
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    • 2001
  • This paper is a generalization of single and two-level skip-lot sampling plans to n-level. On every skipping inspection of the n-level skip-lot sampling plan, not only the number of consecutive lots to be accepted but also the fraction of lots to be inspected can be freely choosed. The general formulas of the operating characteristic function, average fraction inspected, average sample number and average outgoing quality in n-level skip-lot sampling plan are derived. The operating characteristic curves, average sample number and average outgoing quality of a reference plan, two-level and five-level skip-lot sampling plans are compared.

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단상 다중 조합제어 Multi-Level 컨버터의 해석과 시뮬레이션 (Analysis and Simulation of Multi-Level Converter by means of Multiple Single Phase Combination Control)

  • 안일매;전중함;이영호;서기영;이현우
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1999년도 추계학술대회 논문집 학회본부 A
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    • pp.355-357
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    • 1999
  • Single-Phase multi-level AC-DC converter that is composed of diode bridge and switch is proposed. The number of the supply current level is depending on the individual current level of the converter. A converter circuit, the number of the level is equal to $2^{M+1}-1$, where M is the number of Switching Converter. The proposed circuit has converter with 31 current levels. When the number of current level is increased, smoother sinusoidal waveform can be obtained directly and it is possible to control the supply current almost continuously from zero to maximum without generating high voltage step changes as pulse with modulation technology. The technique illustrates its validity and effectiveness through the PSIM.

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부산물 비료의 시비량이 잎들깨의 엽 특성.채엽수 및 연작에 미치는 효과 (Effect of Fertilizer Level of Organic Compost on Leaf Characteristics, Leaf Number and Replanting in Perilla frutescens)

  • 하상영;정대수;박선일;여수진
    • 생명과학회지
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    • 제9권5호
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    • pp.628-637
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    • 1999
  • This study was conducted to elucidate the leaf characteristics, leaf number and fertilizing level in perilla, Perilla frutescens, which was cultivated using five types organic compost with three level. Number of the harvested leaves was effective in Heulgnara with 800 kg/10 and Poongjag with 1200 kg/10 at 70 days and organic compost were the highest in Sarang followed by Heulgnara and Poongjag in order. Number of leaf harvested during the fifth times was the highest Poongjag followed by Heulgnara and Sarang in order. Leaf length and leaf width were the highest in Poongjag with 1200 kg/10 a at 70 days. Simple method for calculation of fertilizer level was N 6.09 kg and slaked lime 36.56 kg in Heulgnara 100 kg per 10 a. Recommendation level of chemical fertilizer in Heulgnara due to fertilizer method was N 275.10 kg, P 4.3 kg and K 10 kg per 10 a.

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반응표면실험을 위한 3-수준 구형(球形) 실험설계: 구형 실험지역의 반경이 요인 수에 따라 변화하도록 구축된 설계 (Some 3-Level Spherical Designs for Response Surface Experiments: Designs Constructed for the Radius of the Spherical Experimental Region to Vary with the Number of Factors)

  • 이우선;임성수
    • 품질경영학회지
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    • 제29권1호
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    • pp.24-40
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    • 2001
  • Response surface designs can be classified, according to the shape of the experimental region, into spherical designs and cuboidal designs. Among the central composite design(CCD)s and the Box-Behnken design(BBD)s that are popular in practice, when the number of factors is k, spherical designs are tile CCDs with the axial value being $\sqrt{\textit{k}}$ and the BBDs, and cuboidal designs are the CCDs with the axial value being 1. With the CCDs having $\sqrt{\textit{k}}$ as the axial value, the radius of the experimental region varies with number of factors, but these designs are the 5-level designs. With the BBDs that are 3-level designs, the radius of the experimental region does not vary with the number of factors. In this article, we propose tile 3-level spherical designs which are constructed so that tile radius of the experimental region varies with the number of factors.

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노년층의 담화 산출 특성: 노화, 성별, 교육정도에 따른 차이 (Discourse Characteristics in Healthy Elderly: Effects of Aging, Gender and Educational Level)

  • 최현주
    • 말소리와 음성과학
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    • 제4권2호
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    • pp.135-143
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    • 2012
  • Discourse is regarded as an important component of communication assessment, but studies about the discourse characteristics of the elderly are scant. The purpose of this study was to confirm the effects of aging, gender, and educational level on discourse in elderly people with normal cognitive function. Forty normal elderly and forty young people participated in this study. A picture description task (Boston Cookie-Theft picture) was used to examine discourse function. The description task was analyzed for both productivity (total number of sentences, total number of syllables, and syllables per sentence) and semantics (CIU ratio). The results were as follows: 1) Only CIU ratio differed significantly according to age. 2) In the total number of syllables and syllables per sentence, females demonstrate a higher number than males. 3) The CIU ratio differed significantly according to educational level. These results suggest that impairment of communicative function is an aspect of cognitive impairment that can be related to aging. Also, discourse performance in the elderly is associated with their gender and educational level.

PRECEDE 모형을 이용한 구강건강의 영향요인에 대한 진단적 연구 (Influencing factors of oral health by PRECEDE model)

  • 조민정
    • 한국치위생학회지
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    • 제13권3호
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    • pp.525-534
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    • 2013
  • Objectives : This study aimed to improve school health program by investigation of several variables through educational diagnostic factors which influence the level of subjective oral health perception and DMFT of students on the basis of PRECEDE model. Methods : A total of 286 high school students in Busan completed the self-reported questionnaire from September 3 to 28 in 2012. Results : 1. Social and epidemiologic diagnosis suggested that the level of subjective oral health perception of male students was not better than that of female students and DMFT number of the male was more than that of the female(p<0.001)(p<0.001). 2. Oral health diagnosis indicated that once a day tooth brushing group showed lower level of oral health perception(p<0.001) and high DMFT number(p<0.001). 3. Predisposing factor of educational diagnosis implied that more than 4 times a day snack intake group and sweet diet and soda friendly group showed lower level of oral health perception and high DMFT number(p<0.001). 4. Tooth brushing of the reinforcing factors had the most important effect on the level of oral health perception and the number of dental caries. Daily snack intake was the most important effect on DMFT number. Conclusions : The informed consent from each family was the important factor in implementing PRECEDE model. School health program improved oral health care. Oral health program can correct the risk oral health behavior in children and adolescents.

대용량 21 레벨 단상 AC/DC 컨버터 (High power 31 level Single Phase AC/DC Converter)

  • 전중함
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2000년도 전력전자학술대회 논문집
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    • pp.309-312
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    • 2000
  • Single-phase multi-level AC-DC converter is proposed that is composed of diode bridge and switch. The number of the supply current level is depending on the individual current level of the converter. A converter circuit the number of the level is equal to $\textrm{2}^{M+1}$-1 The proposed circuit has converter with 31 current levels. When the number of current level is increased smoother sinusoidal waveform can be obtained directly and it is possible to control the supply current almost continuously from zero to maximum without step changes of generating high voltage as pulse width modulation switching loss is decreased it has an advantage in large capacity. it is illustrated technique are confirmed the validity and effectiveness through the simulation & experiments

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