• 제목/요약/키워드: SAW-Less

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

  • Park, Jong-Hu;Kim, C.G.;Cho, B.H.
    • Proceedings of the KIEE Conference
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    • 2002.07b
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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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    • v.14 no.4
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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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    • v.4 no.1
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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.

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

  • Kang Kyung hwa;Baek Geun Gi;Km Kyung Chul;Lee Yong Tae
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.17 no.2
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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.

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

  • Jeong, Byeoung-Koo;Lee, Dae-Hong;Joo, Tae-Hwan
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.29 no.7
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    • pp.500-507
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    • 2018
  • A three-channel radio frequency (RF) monopulse receiver using a data signal with a maximum transmission rate of 274 Mbps was designed. A monopulse receiver using a broadband communication signal was designed to operate in the Ku band, and it consists of a down-conversion module and a signal-processing module. To satisfy the performance of the proposed RF monopulse receiver, a signal-processing function less than the reception sensitivity for each transmission rate according to the adaptive transmission rate is required. To minimize signal reception and mutual frequency interference of various bandwidths, two RF filters were applied. To verify the satisfaction of system requirements, an AWR Corp. simulation tool was used.

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

  • Kim, Taigi
    • Journal of Labour Economics
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    • v.26 no.1
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    • pp.53-73
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    • 2003
  • This paper investigates the success factors of labor mediation using the Survey on the Problems and Improvements of Mediation Service by the Labor Relation Commission which was conducted by the Ministry of Labor in 2000. When the parties of labor and management which took mediation service belong to the manufacturing industry and the Minju-nochong, they are found to have less chance to change their negotiation attitude favorably toward agreement in mediation process and to adopt an agreement proposal made by the mediator. Those who took mediation service more frequently in the past tend to have lower chance to make use of mediation service successfully. Those who saw the mediators of their dispute to be qualified with fairness and expertise tend to have higher chance. As the time of mediation meeting lengthens, it is more likely for them to reach an agreement with assistance by the mediators.

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

  • Kang, Sung-Won;Kim, Myung-Hyun;Shin, Yong-Taek;Lee, Hae-Woo
    • Journal of the Society of Naval Architects of Korea
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    • v.41 no.6
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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.

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

  • 윤형도;한상필;김성구;임영민;윤대원
    • Journal of the Korean Institute of Telematics and Electronics D
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    • v.34D no.11
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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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Apparel Shopping Orientations and Importance of Store Attributes Related to Cognitive Age of the Elderly Consumers (노년층 소비자의 인지연령에 따른 쇼핑성향과 의류점포속성 중요도)

  • 장철진;박제옥
    • Journal of the Korean Society of Clothing and Textiles
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    • v.20 no.1
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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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The Study of Nano-texturing Process for Crystalline Silicon Solar Cell Using Ag Catalyst Layer (결정질 실리콘 태양전지의 Ag 촉매층을 이용한 나노 텍스쳐링 공정에 관한 연구)

  • Oh, Byoung-Jin;Yeo, In-Hwan;Kim, Min-Young;Lim, Dong-Gun
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.25 no.1
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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.