• 제목/요약/키워드: SAW-Less

검색결과 92건 처리시간 0.025초

디지털 PWM 입력 D급 음향 증폭기를 위한 새로운 제어기법 (A novel controller for switching audio power amplifier with digital input)

  • 박종후;김창균;조보형
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2002년도 하계학술대회 논문집 B
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    • pp.976-979
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    • 2002
  • A new controller for switching audio power amplifier with digital PWM input is proposed- Bi-directional Saw-tooth Error Correction (BSEC). This control method for high quality switching amplifier is based on a pulsed edge correction approach using PWM audio signal input as a reference of power switching digital to analog converter. The proposed controller has excellent features such as wide error correction range and no limitation on the modulation index. The controller is implemented in the half-bridge class D amplifier and the performance is verified through hardware experiments. It delivers 100W into 4${\Omega}$ load with less than 0.2% of total harmonic distortion (THD) all over operating range and an maximum efficiency of 82%.

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Testing the Transtheoretical Model in Predicting Smoking Relapse among Malaysian Adult Smokers Receiving Assistance in Quitting

  • Yasin, Siti Munira;Retneswari, Masilamani;Moy, Foong Ming;Taib, Khairul Mizan;Isahak, Marzuki;Koh, David
    • Asian Pacific Journal of Cancer Prevention
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    • 제14권4호
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    • pp.2317-2323
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    • 2013
  • The role of The Transtheoretical Model (TTM) in predicting relapse is limited. We aimed to assess whether this model can be utilised to predict relapse during the action stage. The participants included 120 smokers who had abstained from smoking for at least 24 hours following two Malaysian universities' smoking cessation programme. The smokers who relapsed perceived significantly greater advantages related to smoking and increasing doubt in their ability to quit. In contrast, former smokers with greater self-liberation and determination to abstain were less likely to relapse. The findings suggest that TTM can be used to predict relapse among quitting smokers.

Acceleration of Mounting in Self Mounting Method and Its Effect on Cocooning, Cocoon Characters and Reeling Parameters in Silkworm Bombyx mori L.

  • Himantharaj, M.T.;Das, Kakali;Kumari, K.M.Vijaya;Rajan, R.K.
    • International Journal of Industrial Entomology and Biomaterials
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    • 제4권1호
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    • pp.19-22
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    • 2002
  • Rotary mountages are the best mountages among all the mountages that are used in sericultural areas. But to use this mountage more space, separate mounting hall & requires more labour to pickup the matured worms. to over come these problems, self mounting method is adopted to save the time Er labour, But the mounting rate is generally less. To accelerate the mounting rate different repellents viz; saw dust, phytoecdysone, 1% cresol with paddy husk, lime, kaolin, gormalin chaff were used in the present study. The results indicated that highest number of larvae climbed the mountage in 1% cresol with paddy husk, followed by phytoecdysone and lime. It is observed that the use of repellents at wandering stage accilerates mounting rate and did not affect the quality of the cocoons and reeling characters.

지산선생이 주창한 담 방광 용어에 대한 연구 (Study on the terms, ′Dam′ and ′Bangwang′)

  • 강경화;백근기;김경철;이용태
    • 동의생리병리학회지
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    • 제17권2호
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    • pp.275-292
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    • 2003
  • In terms of Yin and Yang theory, Dam represents excessive Yang and deficient Yin, and Bangkwang means excessive Yin and deficient Yang. In terms of Ki and Hyung, Dam is vigorous Ki and flabby Hyung, and Bangwang is strong Hyung and weak Ki. In terms of the balance of Ki and Blood, Dam is more Ki and less Blood and Bangkwang is the opposite. In terms of meridians concerned, Dam belongs to Joksoyangdam meridian(足少陽膽經) and Bangkwang belongs to Joktayangbangwang meridian(足太膀胱經), Mr. Jeesan saw that the person having vigorous Ki and flabby Hyung tends to be dynamic and the person having strong Hyung and weak Ki tends to be static and designated both as Dam and Bangkwang, respectively, Meridians are the route of Ki and Blood in the body and since their titles are thought to imply basic oriental medical theories, they are better choices to be comprehensive and systematic than other terms. In the 12 meridians, the 6 foot meridians are more important than the other hand meridians because human beings adapt themselves to the earth. Among the 6 foot meridians, the 3 Yang foot meridians are more representative of the body since they cover more of the body. Joksoyangdam meridian(足少陽膽經) is related to more Ki and less Blood and thus is a relevant term to describe Dam. Likewise Joktaeyangbangkwang meridian(足太膀胱經) is related to more Blood and less Ki and thus can correspond to the term 'Bangkwang'. In addition, the Dam organ and Dam meridians meet the condition of excessive Yang and deficient Yin, vigorous Ki and flabby Hyung, more Ki and less Blood, on the other hand, the BangKwang organ and Bangkwang meridians meet the condition of excessive Yin and deficient Yang, strong Hyung and weak Ki, more Blood and less Ki. Thus the terms of Dam and Bangkwang satisfy the basic concepts Mr. Jeesan established.

적응형 전송속도를 갖는 Ku-대역 모노펄스 수신기 설계 (Monopulse Receiver Design with Adaptive Transmission Speed on Ku-Band)

  • 정병구;이대홍;주태환
    • 한국전자파학회논문지
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    • 제29권7호
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    • pp.500-507
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    • 2018
  • 본 논문에서는 유 무인항공기 추적 등에 사용이 가능하며, 전송속도가 최대 274 Mbps에서도 추적이 가능한 3채널 RF 모노펄스 수신기에 대해 설계하였다. 통신용 신호를 이용한 모노펄스 수신기는 Ku-대역으로 설계되었으며, 하향 변환모듈, 신호 처리 모듈로 구성된다. 제안된 RF 모노펄스 수신기의 성능을 만족시키기 위해 전송속도에 따른 전송속도별 수신감도의 신호처리 기능이 구현되었고, 이를 위해 다양한 대역폭의 신호 수신 및 상호 주파수 간섭을 최소화하기 위하여 2종의 RF 필터로 구성된 수신기 구조를 적용하였다. 시스템 요구사항의 만족 여부를 확인하기 위해 AWR 시뮬레이션 툴을 이용하였다.

조정의 성공요인 : 노사분쟁의 경우 (Success Factors of Mediation: Labor Disputes)

  • 김태기
    • 노동경제논집
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    • 제26권1호
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    • pp.53-73
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    • 2003
  • 본 연구는 노동부가 2000년에 실시한 노동위원회 조정서비스의 문제점 및 개선방향에 대한 설문조사 결과를 활용하여 분쟁조정의 성공을 좌우하는 요인이 무엇인지를 분석한다. 분석 결과를 보면 업종이 제조업이거나 노동조합이 민주노총에 소속되어 있는 경우 조정의 성공 가능성이 떨어지는 것으로 나타났다. 조정을 받았던 경험이 많은 사업체일수록 노사 당사자들의 자세가 조정 과정에서 합의에 우호적인 방향으로 바뀔 가능성은 낮고 조정안을 수락하지 않을 가능성은 높은 것으로 나타났다. 노사 당사자들이 조정위원이 공정하고 전문성을 갖추고 있다고 인식할수록 조정회의 시간이 길어질수록 조정이 성공할 가능성이 올라간다.

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해양구조용강재의 SA용접부에서 입열량이 파괴인성에 미치는 영향에 관한 실험적 연구 (The Effect of Heat Input on Fracture Toughness(CTOD) in Submerged Arc Offshore Steel Weldments)

  • 강성원;김명현;신용택;이해우
    • 대한조선학회논문집
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    • 제41권6호
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    • pp.40-47
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    • 2004
  • The influence of heat input on fracture toughness was investigated in SAW weldments, which were prepared at two different welding conditions in API 2W Gr.50 and EN10225 5420. By examining the fracture initiation point, refined areas(ICHAZ and SCHAZ) in weld metal was identified as local brittle zone, in which M-A constituents and coarsed grain size were observed. Impact values showed the most significant difference at root portion, and CTOD transition temperature was related with impact values obtained at root portion. Hardness values in refined area were less than columnar microstructure about 20 HV5.

AOTF용 광도파로 및 IDT 전극제작 (The characteristics of optical waveguides and IDT electrodes fabriacted for acousto-optic tunable filters)

  • 윤형도;한상필;김성구;임영민;윤대원
    • 전자공학회논문지D
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    • 제34D권11호
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    • pp.76-82
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    • 1997
  • The characteristics of optical waeguides and IDT electrodes fabricated for acousto-optic tunable filters (AOTE) used for optical communications were analyzed. A $Ti:LiNbO_3$ in-diffusion method was employed for the formation of the optical waveguide with a dimension of width $8\mu\textrm{m}$, length $30000\mu\textrm{m}$, and thickness $1150{\AA}$. The diffusion was carried at $1050^{\circ}C$ for 8 houss to pattern the optical waveguide with Ti. The resulted waveguide exhibited a single mode at a 1550nm wavelength range and its propagation loss was less than 0.5dB/cm. The width of IDT, with 10 SAW periods, was $5000\mu\textrm{m}$, S11 reflection characteristics and impedances of th eelectrodes deposited with Au were analyzed using a network analyzer; $48.1\Omega$ at th ecenter frquency of 193MHz for Au deposition thickness of $1500{\AA}$ and $50.7\Omega$ at the center frequency of 192MHz for au deposition thickness of $1600{\AA}$.

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노년층 소비자의 인지연령에 따른 쇼핑성향과 의류점포속성 중요도 (Apparel Shopping Orientations and Importance of Store Attributes Related to Cognitive Age of the Elderly Consumers)

  • 장철진;박제옥
    • 한국의류학회지
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    • 제20권1호
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    • pp.28-42
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    • 1996
  • The purposes of this sturfy were 1) to examine the difference between cognitive and actual age, 2) to understand apparel shopping orientations and the importance of store attributes related to cognitive age and 3) to identify relationship.; between apparel shopping orientations and importance of store attribute, ; in cognitively younger and older groups For the study, questionnaires were administered to 450 elderly women over 55 years of age. The questionnaires were designed to mea, ;ore apparel shopping orientations (hedonic, store loyal and brand conscious, careful and planned, confidented and independent, and economic shopping), importance of store attributes, cognitive age and demographics. Using a base of 204 women, data was analyzed by using descriptive statistics, t-test and correlation coeffictents. The results of this study weve summarized as follows. 1. The older women saw themselves on average 6. 6 years younger than they really were 77.6% of the respondents blieved themselves to be cognitively younger 2 Cognitively younger women were more hedonic and less carefull and planned than cognitively older women in apparel Shopping. 3. Cognitively older women thought that proximity and private dressing rooms in apparel stores were mote important attributes than cognitively younger women. In terms of apparel store attributes, older consumers placed importances on product quality, fit and size, design suited to their age, attractive price, and the availability to return unsatisfactory products, in orders.

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결정질 실리콘 태양전지의 Ag 촉매층을 이용한 나노 텍스쳐링 공정에 관한 연구 (The Study of Nano-texturing Process for Crystalline Silicon Solar Cell Using Ag Catalyst Layer)

  • 오병진;여인환;김민영;임동건
    • 한국전기전자재료학회논문지
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    • 제25권1호
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    • pp.58-61
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    • 2012
  • In our report a relatively simple process for fast nano-texturing of p-type(100) CZ- silicon surface using silver catalyzed wet chemical etching in aqueous hydrofluoric acid (HF) and hydrogen peroxide solution($H_2O_2$) at room temperature. The wafers were saw-damaged by NaOH(6 wt%) at $60^{\circ}C$ for 150s. To obtain a nano-structured black surface, a thin layer of silver with thickness of 1 - 10 nm was deposited on the surfaces by evaporation system. After this process the samples were etched in HF : $H_2O_2$ : $H_2O$ = 1:5:10 at room temperature for 80s - 220s. Due to the local catalytic of the Ag clusters, this treatment results in the nano-scale texturing on the surface. This resulted in average reflectance values less than 9% after the silver on the surface of the wafers were removed.