• 제목/요약/키워드: Deat-time Control

검색결과 2건 처리시간 0.016초

Dead-Time 적응제어 기능과 Power Switching 기능을 갖는 DC-DC 부스트 변환기 (DC-DC Boost Converter with Dead-Time Adaptive Control and Power Switching)

  • 이주영;양민재;김두회;윤은정;유종근
    • 한국정보통신학회:학술대회논문집
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    • 한국정보통신학회 2013년도 추계학술대회
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    • pp.361-364
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    • 2013
  • 기존의 DC-DC 부스트 변환기에서 사용되는 non-overlapping gate driver는 dead-time이 고정되어 있기 때문에 body-diode conduction loss 또는 charge-sharing loss가 발생하는 문제점을 가지고 있다. 이러한 손실을 줄이기 위해 사용된 기존의 적응제어 방식의 경우는 CCM 동작 시 전력트랜지스터가 동시에 on이 되는 구간이 발생하여 시스템 효율이 감소하는 문제점이 있다. 따라서 본 논문 에서는 이러한 문제점을 해결할 dead-time 적응제어 기능과 power switching 기능을 갖는 DC-DC 부스트 변환기를 설계 하였다. CMOS 0.35um 공정을 사용하였고, 2.5V 입력으로 3.3V의 출력전압을 얻으며, 스위칭 주파수는 500kHz 이다. 부하전류 150mA일 때 가장 높은 95.3%의 효율을 얻었다. 설계된 회로의 칩 면적은 $1720um{\times}1280um$이다.

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통규탕(通竅湯)이 알레르기 비염 모델 횐 쥐에 미치는 영향 (The Effect of Tongkyu-tang on the Ovalbumin-inhalation Rat Model with Allergic Rhinitis)

  • 정진영;김윤범
    • 한방안이비인후피부과학회지
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    • 제18권2호
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    • pp.36-50
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    • 2005
  • Background and Objectives: Allergic rhinitis is an allergic reaction characterized by sneezingm itchy nose, mouth and throat, congestion and/or nasal discharge. The offending allergenes are usually pollens, molds, dust mites and animal allergen. Recently, the incidence of infectious nasal diseases tend to decrease. However, allergic rhinitis has increased and treatment in most cases has only deat with the symptom. Tongkyu-tang was composed of sixteen crude drugs. The Oriental Medical References mention therapeutic effects of Tongkyu-tang on nasal obstruction, watery nasal discharg. And Tongkyu-tang has clinically been used for the treatment of common cold, headache, sternutation, rhinitis etc. Speacially Tongkyu-tang is one of the most frequently used medical treatment for the allergic rhinitis. Experimental studies were conducted to investigate for the effect of Tongkyu-tang on the changes of neutrophil segment, lymphocyte, total IgE and nassal tissue in allergic rhinitis of ovalbumin-inhalation rat. Meterial and Methods: Fifteen Sprague-Dawley rats were divided into three group: normal group, control group, experimental group. To induce the allergic rhinitis in control group and experimental group, rats were sentitized intraperitoneally with 0.1 % ovalbumin solution 3 times at intervals of I week. Then intranasal sensitization was performed by diffusing 0.1 % ovalbumin solution 3 times at intervals of 2 days. After that time, rat in the experimental group were oral administration treated by Tongkyu-tang for 28 days. We observed changes in nasal tissue; changes in the number of white blood cell, red blood cell and total Ig E; also changes in the segment of neutrophil and lymphocyte in blood. And we observed the changes of AST, ALT of three group. We used anova test statistically. Result: The number of leucocyte remained unchanged between three group. The number of erythrocyte was increased in experimental group and control group when compared with the normal group. The segment of neutrophil, in blood was decreased in experimental group when compared with the control group but, that was not significant statistically(p<0.05). The promotion of lymphocyte in blood was significantly decreased in experimental group when compared with the Control group(p<0.05). Total IgE was decreased in experimental group when compared with the control group but, that was not significant statistically(p<0.05). The cilium be well preserved in experimental group: the nasal tissue in experimental group was similar to in the normal group. Congestion and expantion of grandular cell in nasal submucosa, hypertropy of epithelium in nasal mucosa, acid mucus in epithelium and neutral mucus in subepithelium were decreased in experimental group when compared with the control group. Effect of Tongkyu-tang on the liver function were also studies in rats. Treatment of Tongkyu-lang did not affected on AST and ALT. Conclusion: Considering the above experimental results, it is suggested that oral administration treatment using Tongkyu-lang, without worry about liver function injury, decreased response on an Animal model with Allergic Rhinitis.

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