• 제목/요약/키워드: By-pass

검색결과 3,551건 처리시간 0.034초

다기능성 나노자성복합소재 기술동향 (Technical Trend of Multi-function for Nano-magnetic Material)

  • 김유상
    • 한국표면공학회지
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    • 제45권1호
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    • pp.43-52
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    • 2012
  • Recently, it has been developed for Eco-environment, Super light, Multi-functional nano materials. As needed mobile parts in Smart phone or TV, computer, information communication for high pass signal, multi-function, Magnetic thin film materials have been developed. As last, magnetic powder, sintered and sputtering parts were thick and low purity than electroplating layer, low pass signal and noise were resulted, vibrated TV screen. Because chemical complex temperature was high and ununiform surface layer, it has been very difficult for data pass in High Frequency (GHz) area. Large capacity data pass is used to GHz. Above GHz, signal pass velocity is dependent on Skin Effect of surface layer. If surface layer is thick or ununiform, attachment is poor, low pass signal and cross talk, noise are produced and leaked. It has been reported technical trend of Electrochemically plating and Surface treatment of Metal, Polymer, Ceramic etc. by dispersion/complex for Multi functional nano-magnetic material in this paper.

Compact Low-Pass Filter with Sharp Skirt Characteristics and Broad Stopband

  • Li, Rui;Kim, Dong-Il;Choi, Chang-Mook
    • 한국항해항만학회지
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    • 제30권7호
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    • pp.607-610
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    • 2006
  • A new compact microstrip low-pass filter and its equivalent-circuit model are developed. The philosophy of the structure behind this novel microstrip low-pass filter is simple as it is composed of a pair of symmetrical parallel coupled-line and an open-stub. With this configuration, a finite attenuation pole near the stopband cutoff frequency is available and adjustable by simply tuning the circuit parameters. Furthermore, the rejection bandwidth of this type of low-pass filter can be extended. In order to validate the feasibility of the proposed design method, a low-pass filter based on a microstrip structure is designed, fabricated, and measured. Experimental results agree very well with the simulation and analytical results.

Adaptive Histogram Projection And Detail Enhancement for the Visualization of High Dynamic Range Infrared Images

  • Lee, Dong-Seok;Yang, Hyun-Jin
    • 한국컴퓨터정보학회논문지
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    • 제21권11호
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    • pp.23-30
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    • 2016
  • In this paper, we propose an adaptive histogram projection technique for dynamic range compression and an efficient detail enhancement method which is enhancing strong edge while reducing noise. First, The high dynamic range image is divided into low-pass component and high-pass component by applying 'guided image filtering'. After applying 'guided filter' to high dynamic range image, second, the low-pass component of the image is compressed into 8-bit with the adaptive histogram projection technique which is using global standard deviation value of whole image. Third, the high-pass component of the image adaptively reduces noise and intensifies the strong edges using standard deviation value in local path of the guided filter. Lastly, the monitor display image is summed up with the compressed low-pass component and the edge-intensified high-pass component. At the end of this paper, the experimental result show that the suggested technique can be applied properly to the IR images of various scenes.

A Novel Design of Compact Low-Pass Filter and Its Equivalent Circuit Model

  • Li, Rui;Kim, Dong-Il;Choi, Chang-Mook;Song, Young-Man
    • 한국항해항만학회:학술대회논문집
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    • 한국항해항만학회 2006년도 Asia Navigation Conference
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    • pp.79-84
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    • 2006
  • A novel design of compact low-pass filter based on microstrip structure and its equivalent-circuit model are developed. The philosophy of the structure behind this novel microstrip low-pass filter is simple as it is composed of a pair of symmetrical parallel coupled-line and an open-stub. With this configuration, a finite attenuation pole near the stopband cutoff frequency is available and adjustable by simply tuning the circuit parameters. Furthermore, the rejection bandwidth of this type of low-pass filter can be extended. In order to validate the feasibility of the proposed design method, a low-pass filter based on a microstrip structure is designed, fabricated, and measured. Experimental results agree very well with the simulation and analytical results.

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A Realization of Biquadratic Voltage Transfer Functions Using Three CCIIs

  • Higashimura, Masami;Fukui, Yutaka
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2000년도 ITC-CSCC -1
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    • pp.151-154
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    • 2000
  • This paper proposes a novel circuit configuration realizing biquadratic voltage transfer functions using three CCIIs and six passive elements. The circuits realize high-pass, band-pass, low-pass, band-stop and all-pass functions by selecting input voltages. The circuit has low passive sensitivities and permits orthogonal adjustment of quality factor Q and cutoff angular frequency $\omega$$\sub$o/. The effects of non-ideal CCIIs on biquadratic transfer functions are also given.

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단층치료기를 이용한 방사선 치료의 환자별 정도관리 평가를 위한 감마인덱스의 정량화 방법 (A Method to Calculate a Pass Rate of the ${\gamma}$-index Analysis in Tomotherapy Delivery Quality Assurance (DQA))

  • 박달;김용호;김원택;김동원;김동현;전호상;남지호;임상욱
    • 한국의학물리학회지:의학물리
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    • 제21권4호
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    • pp.340-347
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    • 2010
  • 단층치료기(TomoTherapy$^{(R)}$)를 이용한 방사선 치료에서 환자별 정도관리인 DQA (delivery quality assurance)는 보통 이온 전리함과 필름을 이용한다. DQA의 결과는 치료계획장비인 TomoPS (Tomo Planning Station)를 이용하여 분석하게 되는데 필름을 이용한 2차원 선량분포의 비교는 감마인덱스 분석을 사용한다. 감마인덱스를 이용한 비교는 3%/3 mm와 같은 기준을 사용하여 이 기준을 통과한 비율(pass rate)이 허용 값보다 크게 되는지 확인한다. TomoPS는 pass rate 값을 정량적으로 계산해주는 기능이 없다. 본 논문에서는 TomoPS 감마인덱스 분석의 pass rate를 정량적으로 계산하는 방법을 제시하고 이를 계산해주는 프로그램인 PassRT를 개발하였다. PassRT의 검증을 위해 I'mRT MatriXX (IBA Dosimetry, Germany)를 사용하여 측정한 세기조절방사선 치료를 받은 환자의 환자별 정도관리 자료와 필름을 사용한 DQA 자료를 사용하였다. 두 가지 종류의 자료에 대해 PassRT로 계산한 pass rate를 OmniPro I'mRT (IBA Dosimetry, Germany)프로그램으로 계산한 pass rate와 비교하였다. MatriXX를 이용하여 측정한 자료의 비교결과 평균오차 0.00%, 표준편차 0.01%, 최대오차 0.04%였고, 필름의 결과는 평균오차 0.00%, 표준편차 0.02%, 최대오차 0.02%였다. 관심영역이 $24.3{\times}16.6cm^2$ 보다 작은 경우 본 논문에서 제시한 방법으로 감마인덱스 분석의 pass rate를 소수점 첫째자리 까지 정확하게 계산할 수 있어서 보다 정확한 단층치료기의 DQA에 도움이 될 것으로 생각된다.

도로교통 소음원에 의한 저주파 소음실태 (Low Frequency Pass-by Noise for Road Vehicle)

  • 정성수;서상준;조문재;김용태
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2003년도 추계학술대회논문집
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    • pp.533-536
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    • 2003
  • The Low frequency(1-200 Hz) noise levels radiated by road traffic were investigated. The results showed that the peak pass-by noise of truck with speed of 60km/h was about 75㏈. For the infra-sound frequency range, the noise was about 65㏈ and it was less value than expected. But the noise level will be increase as increasing the speed. The pass-by noise for train was also measured for comparison. The peak train noise was about 95㏈ and it will be enough noise level for a human body to give nuisance.

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동일 전열면적을 갖는 용접식 판형열교환기와 관류형 열교환기의 성능 비교 (Performance Comparison of a Welded Plate Heat Exchanger and Shell and Tube Heat Exchanger with Same Heat Transfer Area)

  • 함정균;김민준;안성국;조홍현
    • 한국지열·수열에너지학회논문집
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    • 제15권4호
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    • pp.46-54
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    • 2019
  • In this study, the performance of a shell and tube heat exchanger (STHE) and welded plate heat exchanger (WPHE) was measured experimentally. The pass numbers of the STHE was changed by 1, 2 and 4. As a result, the WPHE showed 2.1 times higher heat exchange capacity than that of the STHE. In case of pressure drop, the STHE with 1 and 2 pass number has a lower pressure drop than the WPHE, while the STHE with 4 pass presented higher pressure drop than the WPHE. The performance index considering the heat exchange capacity and pump consumption power, showed in oder of STHEPass1 > STHEPass2 > W PHE > STHEPass4 under the same flow rate. Therefore, when the WPHE was designed optimally under same operating condition with STHE, the maintenance fee and space can be reduced effectively by using the WPHE.

Simulated Indoor Pass-by 시스템에서의 최적 Microphone Array 형태와 검증

  • 유윤선
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2009년도 추계학술대회 논문집
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    • pp.225-228
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    • 2009
  • The simulated indoor pass-by noise measurement system is the tool to measure and evaluate the pass-by noise at the test laboratory, without doing measurement at the field. This measurement system can realize the precision measurement under the specific condition and overcome the limitations of the field measurement, i.e. weather conditions, repeatability, .. This measurement system is done in time domain process using the array techniques, which synchronizes the time signals. The reliability of the obtained result depends on the array shapes, which can generate the moving source effect. In this paper, the validations are checked focusing the time domain synchronization of the signals with the optimum microphone array shape.

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Harmonic Suppression and Broadening Bandwidth of Band Pass Filter Using Aperture and Photonic Band Gap Structure

  • Seo, Chul-Hun
    • Journal of electromagnetic engineering and science
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    • 제5권4호
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    • pp.208-212
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    • 2005
  • In this paper, we introduced a band-pass filter employed the PBG structure and the aperture on the ground together. The harmonics of band pass filter have been suppressed by employing the PBG structure and the bandwidth of it has been broadened by using the aperture on the ground. The designed PBG cells have three different sizes. The largest cells, the middle cells, and the smallest cells have suppressed the multiple of second harmonics, the multiple of third harmonics, and the multiple of fifth harmonics, respectively. The center frequency has been 2.18 GHz. The bandwidth has been increased from 230 MHz up to 310 MHz(80 MHz, about $35\%$) by the aperture and the ripple characteristics in passband have been improved and the harmonic frequencies have been suppressed about 30 dB by the PBG.