• Title/Summary/Keyword: Active Period

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Single Current Sensor Technique considering a Snubber Current and a Modified SVPWM Inverter for AC Motor Drives (스누버 전류를 고려한 개선된 SVPWM 인버터를 이용한 상전류센서없는 전동기 구동)

  • 주형길;신휘범;안희욱;윤명중
    • Proceedings of the KIPE Conference
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    • 1999.07a
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    • pp.399-402
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    • 1999
  • The single sensor technique reconstructing phase currents from the dc-link current without phase current sensors in proposed. When the duration of active vector is too short for the snubber current to reduce, the dc-link current including the snubber current gives large detection error. The solution is presented by analyzing the snubber current and modifying the switching sequences. This scheme is simple, requires only one sampling a period and has good results for detecting the phase currents.

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Single Sensor Current Control for Three-Phase Voltage-Source PWM Converters Using a Predictive State Observer (예측 상태 관측기를 이용한 3상 전압 원 PWM 컨버터의 단일 센서 전류 제어)

  • 이우철;현동석;이택기
    • Proceedings of the KIPE Conference
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    • 1999.07a
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    • pp.489-492
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    • 1999
  • This paper proposes a control method for three-phase voltage-source PWM converters using only a single current sensor in the DC link. A predictive current controller for the voltage-source PWM converter is used so that all phase currents can be reconstructed in a switching period although one or two of active vectors are applied only for a short time. Compensation of the 2 step delays is also included. In this paper single sensor current control using predictive state observer will be discussed, and investigated experimentally.

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Dual Mode AMOLED Pixel Circuit

  • Bae, Byung-Seong;Son, Yong-Duck;Jang, Jin;Lee, Ki-Yong;Chung, Ho-Kyoon
    • 한국정보디스플레이학회:학술대회논문집
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    • 2006.08a
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    • pp.1082-1085
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    • 2006
  • We proposed dual mode pixel circuit in AMOLED (active matrix organic light emitting device). After light emitting period of OLED, we used it as a photo sensor. We measured photo current of OLED and simulated the proposed pixel circuit to verify it's function of dual mode, that is lighting and sensing.

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Identification of Dynamic Load Model Parameters Using Particle Swarm Optimization

  • Kim, Young-Gon;Song, Hwa-Chang;Lee, Byong-Jun
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • v.10 no.2
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    • pp.128-133
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    • 2010
  • This paper presents a method for estimating the parameters of dynamic models for induction motor dominating loads. Using particle swarm optimization, the method finds the adequate set of parameters that best fit the sampling data from the measurement for a period of time, minimizing the error of the outputs, active and reactive power demands and satisfying the steady-state error criterion.

Mechanism of Action of and Resistance to Aminoglycoside Antibiotics

  • Tanaka, Nobuo
    • Archives of Pharmacal Research
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    • v.6 no.1
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    • pp.93-102
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    • 1983
  • Waksman's group discovered SM in 1944, and opened a new field of antibiotcs: i. e. AGs. A large group of antibiotics containing aminosugar and/or aminocyclitol is called the AGs. A majority of AGs are produced by actinomycetes. In the first period, AGs effective against tuberculosis were chiefly examined. Following the studies on NM and KM, AGs active against staphyllococci and gram-negative robs were investigated. The discovery of GM and synthesis of DKB and AMK led to the studies on the third generation AGs, which show a broad antimicrobial spectrum including Pseudomonas aeruginosa and drug-resistant bacteria. Since opportunistic infection caused by drug-resistant bacteria are increasing, the third generation AGs are extensively investigated at present.

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Design and Performance Analysis of a Traffic-based Power Saving Mode Decision Algorithm for Energy-efficient Home Networks (에너지 효율적인 홈 네트워크를 위한 트래픽 기반 전력 절감 모드 결정 알고리즘의 설계 및 성능 분석)

  • Kong, In-Yeup;Hwang, Won-Joo
    • Journal of Korea Multimedia Society
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    • v.11 no.10
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    • pp.1392-1402
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    • 2008
  • Home gateway is always full-powered for ubiquitous home services, and consumes much energy yearly. Power-saving algorithm to conserve this energy must reduce the energy consumption and preserve always-on services. Our algorithm predicts current idle period using the history of the past idle period when the idle period starts, and then determines whether the power mode is changed to the saving mode or not. On the power saving mode, it processes the simple protocol data for network control using proxying with no wakeup. And it changes the power mode to active mode when user's traffic exists. As the results of the simulation using real traffic, our algorithm saves the energy consumption from 14% to 49% as compared with existing method.

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The Modernization of the Korean Housing Under the Japanese Colonial Rule

  • Sohn, Sei-Kwan;Jun, Nam-Il;Hong, Hyung-Ock;Yang, Se-Hwa
    • International Journal of Human Ecology
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    • v.7 no.1
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    • pp.1-12
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    • 2006
  • The numerous changes made during the Japanese colonial rule became the basis of the current housing in Korea. Therefore, in order to understand the modern Korean housing, it is essential to understand what the Korean traditional life styles admitted or changed, and how the foreign culture of that time influenced the Korean housing under the Japanese colonial rule. Content analysis through literature review was utilized for the study, and specific sources were research papers, books, magazines, newspapers, and novels. The period during the Japanese invasion was the most active era of modernization in the Korean history. For the housing culture, especially, it can be considered as the most significant period that accepted new housing cultures that replaced the old traditional housing. The Japanese and the Western styles of housing were introduced, new materials and collective production methods were used, and the symbol of the current urban housing in Korea, multi-family dwelling, was constructed. In conclusion, the Koreans did not directly use the Japanese and western housing culture, which were constructed during the Japanese colonial period. They were adapted and altered into Korean style, and eventually, produced various eclectic housing styles.

ORBITAL PERIOD VARIATION AND MORPHOLOGICAL LIGHT CURVE STUDIES FOR THE W UMa BINARY BB PEGASI

  • Hanna, Magdy A.;Awadalla, Nabil S.
    • Journal of The Korean Astronomical Society
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    • v.44 no.3
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    • pp.97-108
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    • 2011
  • The photometric light curves of the W-type W UMa eclipsing contact binary system BB Pegasi have been found to be extremely asymmetric over all the observed 63 years in all wavelengths UBVR. The light curves have been characterized by occultation primary minima. Hence, the morphology of these light curves has been studied in view of these different asymmetric degrees. The system shows a distinct O'Connell effect, as well as depth variation. A 22.96 years of stellar dark spots cycle has been determined for the system. Almost the same cycle (22.78 yr) has been found for the depth variation of MinI and MinII. We also present an analysis of mid-eclipse time measurements of BB Peg. The analysis indicates a period decrement of $5.62{\times}10^{-8}$ day/yr, which can be interpreted in terms of mass transfer at a rate of $-4.38{\times}10^{-8}M_{\odot}$/yr, from the more to the less massive component. The O - C diagram shows a damping sine wave covering two different cycles of 17.0 yr and 12.87 yr with amplitudes equal to 0.0071 and 0.0013 day, respectively. These unequal durations show a non-periodicity which may be explained as a result of magnetic activity cycling variations due to star spots. The obtained characteristics are consistent with similar chromospherically active stars, when applying the Applegate's (1992) mechanism.

A Study on the Fashion Illustration Applied Visual Image of the Traditional Korean Mask (한국의 탈이 지닌 시학적 이미지를 적용한 Fashion Illustration 연구)

  • 주성희
    • The Research Journal of the Costume Culture
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    • v.2 no.2
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    • pp.265-282
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    • 1994
  • The mask used in drama has been reappreciated, and it needs profound and systematic studies in order to form the mask to effective use. In research, the aesthestic values in the masks of he latter period of Chosun(the mideighteenth century-the early nineteenth century) was examined through the analysis of traditional drama in accordance with the historical social background. In the later period of Chosun, the active performance of the mask in company with the occurrence of a popular movement caused by people's self-awakening showed a close relationship between the development of the mask and its historical background the moulding characteristic of the mask was analysed before and after the eighteenth century, and regionally in the south and in the middle and the north. The mask express the quality of art before he eighteenth century. It showed, on the other hand, a strong social nature and a touch of satires on society in the south and a religional interest in he middle and the north. This study shows from the viewpoint of a aesthetics that traditional Korean mask during Chosun period had comfortable and voluminous forms with beauty curved lines and colors and rhythm. The aesthetic values in mask as expressed through the aesthetic characteristics have been classified the beauty of nature the beauty of personality, the beauty of traditions. Visual image with these beauty in masks were expressed into fashion illustration of suits and dresses.

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The Role of Vitamins and Minerals in the Production of High Quality Pork - Review -

  • Mahan, D.C.;Kim, Y.Y.
    • Asian-Australasian Journal of Animal Sciences
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    • v.12 no.2
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    • pp.287-294
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    • 1999
  • Vitamin and mineral deletion from swine diets can result in reduced growth if done during the period wher muscle and bone development is occurring. Several of the vitamins and minerals decline in the serum during the starter period, suggesting a higher dietary inclusion may be necessary postweaning. Vitamin research with grower-finisher pigs is limited, but results suggest that rapidly growing lean pigs may have a higher dietary requirement for the B vitamins. Several studies have suggested that early weaning and pigs of a lean genotype may have a dietary requirement for vitamin C, CI and Cr. High dietary vitamin E levels are fortified in the diet and seems to be effective in preventing mulberry heart problems in weanling and grower pigs. Organic Se is more effectively retained in muscle tissue than inorganic Se, approximately 20% less is excreted, but the bioavailability of organic Se for glutathione peroxidase activity is only 80 to 90% to that of sodium selenite. The active form of thyroxine (T4) is dependent upon a Se containing enzyme. Withdrawal of vitamins and minerals during the latter part of the finisher period has not affected pig performance responses, but studies with poultry suggest that the vitamin content of the meat may be reduced if the vitamins are withdrawn prior to marketing. High levels of vitamin E have been shown to improve pork quality, by reducing drip loss. Studies with vitamin C and Se have suggested that they may also be involved in pork quality.