• 제목/요약/키워드: Power Plane

검색결과 945건 처리시간 0.034초

Design of Power Plane for Suppressing Spurious Resonances in High Speed PCBs

  • Oh Seung-Seok;Kim Jung-Min;Yook Jong-Gwan
    • Journal of electromagnetic engineering and science
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    • 제6권1호
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    • pp.62-70
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    • 2006
  • This paper presents a new power plane design method incorporating a single geometry derived from a unit cell of photonic bandgap(PBG) structure. This method yields constantly wide suppression of parallel plate resonances from 0.9 GHz to 4.2 GHz and is very efficient to eliminate PCB resonances in a specified frequency region to provide effective suppression of simultaneous switching noise(SSN). It is shown that with only two cells the propagation of unwanted high frequency signals is effectively suppressed, while it could provide continuous return signal path. The measured results agree very well with theoretically predicted ones, and confirm that proposed method is effective for reducing EMI, with measured near-field distribution. The proposed topology is suitable for design of high speed digital system.

침-평판 전극 구조에서 발생하는 기중 코로나 방전의 해석 기법 (Analysis Techniques of Corona Discharges in Air with Needle-Plane Electrode System)

  • 강성화;박영국;권순석;정수현;류부형;임기조
    • 한국안전학회지
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    • 제11권4호
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    • pp.49-53
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    • 1996
  • Corona discharges in air insulated electric power systems cause power loss, produce interfering electromagnetic radiation, and can indicate incipient failure. An understanding of corona discharges in air gap is clearly Important. The Wavelet transformation is an extended method of fourier transformation. The fourier method is a powerful tool for signal analysis, but it can't include information for time. However the wavelet transformation analysis can include on the information of time and frequencies at the same time. In this paper we apply the wavelet transformation to the corona signals in needle-plane air gap for the purpose of analysis of developing aspects of corona discharges. We analyzed the developing aspects of corona discharges, namely, corona discharge current, repetition rates, width of Pulse distribution region, pulseless region and frequencies distribution of corona discharge pulses.

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레이저 토모그래피와 화염구조선도에 의한 연소영역의 검토 (A Discussion of Combustion Regime Based on Laser Tomography and Flame Structure Diagram)

  • 김준효
    • 동력기계공학회지
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    • 제2권1호
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    • pp.17-24
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    • 1998
  • The combustion regime was discussed using a laser tomography and flame structure diagram. It was shown first how to represent the turbulent burning velocity and flame structural parameters in the dimensionless plane referred to as the flame structure diagram. And then, turbulent flame structure from the obtained images by laser tomography was compared with combustion regime in the Re-Da plane, one of the diagrams, specified by different researchers. As the result, the $u'/S_{L0}$ ratio at the boundary between the wrinkled laminar flame regime and reactant islands flame regime was found to be about 1.5.

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An LED SAHP-based Planar Projection PTCDV-hop Location Algorithm

  • Zhang, Yuexia;Chen, Hang;Jin, Jiacheng
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제13권9호
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    • pp.4541-4554
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    • 2019
  • This paper proposes a planar projection DV-hop location algorithm (PTCDV-hop) based on the LED semi-angle at half power (SAHP, which accounts for LED SAHP characteristics in visible light communication (VLC)) and uses the DV-hop algorithm for range-free localization. Distances between source nodes and nodes positioned in three-dimensional indoor space are projected onto a two-dimensional plane to reduce complexity. Circles are structured by assigning source nodes (projected onto the horizontal plane of the assigned nodes) to be centers and the projection distances as radii. The proposed PTCDV-hop algorithm then determines the position of node location coordinates using the trilateral-weighted-centroid algorithm. Simulation results show localization errors of the proposed algorithm are on the order of magnitude of a millimeter when three sources are used. The PTCDV-hop algorithm has higher positioning accuracy and stronger dominance than the traditional DV-hop algorithm.

견갑면에서의 견관절 외전정도에 따른 등속성회전운동의 근력 평가 (An Evaluation for Isokinetic Strength During Shoulder Rotation Movement in the Scapular Plane with Various Abduction)

  • 최재원;김수민;김현애;김경;황보각;배성수
    • The Journal of Korean Physical Therapy
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    • 제12권2호
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    • pp.95-105
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    • 2000
  • Glenohumeral internal and external rotation with shoulder abducted in the frontal plane often causes impingement of the supraspinatus tendon. whereas similar activity in scapular plane does not cause impingement. The Purpose of this study was to determine if assessment among the three positions as 30 degrees, 60 degrees, 90 degrees abduction in the sitting position of the scapular plane could be affected the comparison between intemal and external peak torque, total work, average power. In this study, Isokinetic shoulder rotational strength was evaluated in twenty healthy male university students, using the Cybex NORMTM System (CYBEX Division of LUMEX, Inc., Ronkonkoma, New York). Test data was gathered in the plane of the scapular, 30 degrees of horizontal flexion anterior to coronal plane, and the subjects performed the test with the arm 30, 60, and 90degrees abducted in the sitting position. also, test speed was set at deg/sec. Statistical analysis was performed using SPSS 7.5 for Windows software and mean and standard deviations were calculated. ANOVA was used to analyze the difference of the values in the three test positions. A paired t-test was used of examining the difference in the means peak torque between external and internal rotation. Not any significant difference was found among three abduction positions in scapular plane, even though there was a consistent pattern of greater strength in the abducted position of 60 degrees. Internal relation strength peak torque and total work were greater than those of external rotation in every test positions.

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한국과 미국 임대아파트 평면의 특징비교 - 양천구 SH공사 아파트와 Saint Paul PHA 아파트를 중심으로 - (A Study on the Types of Unit Plans in Rental Housing - Focused on Rental Housing in SH Corporation and Public Housing in PHA -)

  • 신경주;문학조
    • 한국실내디자인학회논문집
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    • 제16권6호
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    • pp.86-95
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    • 2007
  • The objective of this research is to provide basic materials for future development of unit household plane of lease apartment house by comparing and analyzing the unit household plane of SH Corporation lease apartment house in Korea and PHA apartment house in the state of Minnesota, USA. For this purpose, the researcher chose 8 SH Corporation lease apartment houses in Yangcheon-gu Korea and 16 PHA apartment houses in St. Paul, Minnesota, USA. Drawing of 8 complexes of Korea SH Corporation, literary materials collected by Korea House Corporation and SH Corporation and the plane of USA were analyzed and the unit household plane of Korea and USA were processed by CAD to ensure exact analysis. Based on the drawing for CAD, the materialization work was implemented. The total size of materialized drawing and size of each room was drawn by using 'CAD POWER 2005' program. The result of this research is as follows. The plane of SH Corporation lease apartment house shows the difference in the plane composition from 12 pyung. Since LIVING ROOM is described in the drawing, the living room and bedroom seen in the existing size less than 12 pyung become independent as they are separate. While SH Corporation is composed in the form of kitchen that functions as dining room, living room functions as dining room in PHA. While SH Corporation shows 5 types, PHA shows different pattern in each complex. This is probably because PHA has diverse complexes. All planes of SH Corporation have entrance, which reflect the own character of Korea as it is. In PHA, the portion of receipt and storage space is very high.

패치와 접지면 사이에 삽입된 핀 배열을 가지는 안테나의 방사특성에 핀 반경이 미치는 효과 (Effect of the Pin Radius on the Radiation Characteristics of a Patch Antenna with an Array of Pins Interconnecting the Patch and the Ground)

  • 이우람;김태영;김부균;신종덕
    • 대한전자공학회논문지TC
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    • 제45권10호
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    • pp.80-89
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    • 2008
  • 패치와 접지면 사이에 삽입된 핀 배열을 가지는 패치안테나 (핀 배열 패치안테나)를 제작하고 특성을 측정하였다. 핀 배열 패치안테나가 일반적인 패치 안테나와 비교하여 E-평면의 수평방향으로 방사는 약 10 dB 이상 억제되고 H-평면의 수평방향으로 방사도 약 4 dB 이상 억제됨을 볼 수 있었다. 또한 전방으로의 방사는 증가하고 후방으로의 방사는 감소하여 안테나의 지향성이 향상됨을 볼 수 있었다. Half-power beamwidth가 E-평면 과 H-평면 모두에서 대폭 작아져 방사패턴 특성이 향상됨을 볼 수 있었다. 핀 배열 패치안테나에 삽입하는 핀 반경을 증가시키면 공진 주파수가 증가함을 볼 수 있었다. 또한 기판의 특성에 따라 수평방향으로의 방사억제 효과가 최대가 되는 최적 핀 반경 값이 존재함을 볼 수 있었다.

전면의 conic 계수 변화가 착락원 크기에 미치는 영향 (The Influence of the Variation of Conic Coefficient of the Front Surface on RMS Spot Diameter)

  • 박성종;주석희;심상현
    • 한국안광학회지
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    • 제8권2호
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    • pp.77-83
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    • 2003
  • 본 연구에서는 안경렌즈 전면의 conic 계수 변화에 따른 상측정점초점면에서의 착락원 직경 변화를 조사하기 위해 Code V와 LOSA 2.9 프로그램을 사용하였다. 이때 상측정점굴절력은 -4.00D이고 직경은 70mm인 근시교정용 안경렌즈를 고려하였으며, 전면 굴절력은 2.00D, 4.00D, 6.00D, 그리고 8.00D인 경우를, 굴절률은 $n_d$=1.498, 1.523, 1.586, 그리고 1.660인 경우를 각각 고려하였다. 최적 conic 계수를 사용한 비구면 렌즈의 경우에 상측정점초점면에서의 착락원 크기가 구면렌즈의 경우 보다 작아졌으며, 가장자리의 두께는 감소하였다. 또한 전면굴절력이 작을수록 상측정점초점면에서의 착락원의 크기가 감소하였다. 이러한 결과들로부터 상측점검초점면에서의 착락원 직격을 최소화하여 광학적 결상능력을 향상시킬 수 있는 최적 conic 계수를 결정하였다.

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접지된 유전체 평면위의 스트립 양끝에서 0 저항율을 갖는 저항띠 격자구조에 의한 H-분극 산란 (H-Polarized Scattering by a Resistive Strip Grating with Zero Resistivity at Strip-Edges Over a Grounded Dielectric Plane)

  • 윤의중
    • 한국항행학회논문지
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    • 제15권3호
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    • pp.349-354
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    • 2011
  • 본 논문에서는 스트립 폭과 격자주기, 유전체 층의 비유전율과 두께, 그리고 transverse electric (TE) 평면파의 입사각에 따른 접지된 유전체 평면위의 스트립 양끝에서 0 저항율을 갖는 저항띠 격자구조에 의한 H-분극산란 문제를 Fourier-Galerkin Moment Method (FGMM)를 이용하여 해석하였다. 저항띠의 변하는 저항율은 저항띠의 양끝에서 0으로 변하는 경우를 취급하였고, 이때 저항띠 위에서 유도되는 전류밀도는 직교다항식의 일종인 2종 Chebyshev 다항식의 급수로 전개하였다. 반사전력의 급변점들은 공진효과에 기인한 것으로 과거에 wood's anomallies라고 불리워지며, 반사전력에 대한 수치결과들은 기존 논문의 균일 저항율의 수치 결과들과 비교하였다.

상호 결합을 이용한 광대역 E-면 H 섹터 혼 위상 배열 안테나 설계 (The Design of a Broadband E-plane H Sectoral Horn Phased Array Antenna Using Mutual Coupling)

  • 이철수;백정기
    • 한국전자파학회논문지
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    • 제18권6호
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    • pp.620-628
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    • 2007
  • H 섹터 혼 안테나는 일정한 빔 커버리지를 가지면서 빔 조향을 하는 광대역 위상 배열 송신기의 복사 소자로 유용하다. 본 논문에서는 상호 결합을 이용하여 3:1 주파수 대역과 ${\pm}60^{\circ}$의 빔 조향 범위를 갖는 광대역 E-면 H 섹터 혼 위상 배열 안테나를 설계하였다. 주자계면에서 반전력 빔 폭이 $30{\sim}50^{\circ}$을 갖는 H 섹터 혼 안테나를 설계하였다. 도파관 시뮬레이터를 이용하여 상호 결합을 포함하는 능동 반사 계수를 계산하였고, 광대역 주파수 범위에서 상호 결합에 의하여 능동 반사 특성이 개선되었다. 이러한 결과를 이용하여 $8{\times}1$ H 섹터 혼 위상 배열안테나를 제작하였다. 주자계면에서의 반전력 빔 폭과 능동 반사 계수의 측정 결과는 시뮬레이션 결과와 잘 일치하였다. 빔 조향된 복사 빔들의 첨두치 패턴은 능동 소자 패턴과 잘 일치하였다. 3:1 주파수 대역과 빔 조향 범위에서 능동 반사 계수는 대부분 0.3 이하로 측정되었다.