• 제목/요약/키워드: Scan method

검색결과 1,528건 처리시간 0.029초

표시기간 중첩 프라이밍 구동기술에 의한 플라즈마 디스플레이 패널의 고속구동특성 (High-Speed Characteristics of Plasma Display Panel using Priming Overlapping with Display Drive Method)

  • 염정덕
    • 전기학회논문지
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    • 제56권11호
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    • pp.2004-2009
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    • 2007
  • A new high-speed drive method for the plasma display panel is proposed. In this method, the address period is inserted for the rest period of the sustain pulses and the priming pulse is applied on the entire panel at the same time overlapping with the sustain period. The ramp shaped priming pulse can be made with a simple drive circuit in this technology and the stable sustain discharge can be induced even by a narrow scan pulse in help of the space charge generated from the address discharge. From the experiments, it is ascertained that the priming pulse hardly influences the sustain discharge. Moreover, the voltage margin of the sustain discharge is almost constant though that of the address discharge broadens with narrowing the scan pulse width. And, if the time interval between the scan pulse and the sustain pulse is within $6{\mu}s$, the voltage margin of the address and the sustain discharges are unaffected though the applied position of the scan pulse is changed. High-speed driving with the address pulse of $0.7{\mu}s$ width was achieved and the address voltage margin of 20V and the sustain voltage margin of 10V were obtained.

Test-per-clock 스캔 방식을 위한 효율적인 테스트 데이터 압축 기법에 관한 연구 (A Study on Efficient Test Data Compression Method for Test-per-clock Scan)

  • 박재흥;양선웅;장훈
    • 대한전자공학회논문지SD
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    • 제39권9호
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    • pp.45-54
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    • 2002
  • P45 본 논문에서는 SOC의 내장된 코어를 테스트하기 위한 새로운 DFT 방법인 순차적 테스트 데이터 압축 방법을 제안한다. 순차적 테스트 데이터 압축 방법은 테스트 데이터양을 줄이기 위하여 공유 비트 압축과 고장 무검출 패턴 압축 방법을 이용하였다. 그리고 순차적 테스트 데이터 압축 방법을 이용하는 회로는 스캔 DFT 방법을 기반으로 하고 있으며, test-per-clock 방법을 적용하여 매 클럭마다 테스트 할 수 있는 구조를 가지고 있다. 제안된 압축 방법의 실험을 위하여 벤치마크 회로인 ISCASS85와 ISCASS89 완전 스캔 버전을 이용하였으며, ATPG와 고장 시뮬레이션을 위하여 ATALANTA를 사용하였다. 실험 결과 순차적 테스트 데이터 압축 방법의 테스트 데이터의 양이 스캔 DFT를 적용한 회로에 비해 최대 98% 까지 줄어듦을 확인하였다.

악성 골 및 연부조직 종양에서 Tl-201 SCAN의 진단적 효능 - Tc-99m-MIBI 및 Tc-99m-MDP scan과의 비교 - (Thallium-201 Scan in Bone and Softtissue Sarcoma - Comparison with Tc-99m-MIBI and Tc-99m-MDP Scan -)

  • 신덕섭;조인호;안종철;안면환;이상호
    • 대한골관절종양학회지
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    • 제2권1호
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    • pp.1-7
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    • 1996
  • PURPOSE : The purpose of this study is to know the ability of detecting malignant tumor tissue by Tl-201 scan, and to compare with that of Tc-99m-MIBI and Tc-99m-MDP scan. MATERIAL AND METHODS : Between February 1994 and December 1995,38 unselected patients with various bone pathologies were studied prospectively. Eighteen had malignant bone and soft tissue pathologies, while twenty had benign. All patients were studied with Tl-201, Tc-99mMIBI and Tc-99m-MDP scan prior to surgical biopsy. PICKER Prism 2000 gamma camera with high resolution parallel hole collimator was used for scanning. To avoid the interaction of isotope, the early(30min.) and delayed phase(3hrs.) of Tl-20l scan was performed first and Tc-99m-MIBI scan was performed after 30 minutes, and then Tc-99m-MDP scan 48 hours later. The scan images were visually evaluated by a blinded nuclear medicine physician. We could find true positive, true negative, false positive and false negative by the comparison of results with those of biopsy. We calculated positive and negative predictive value(%), sensitivity(%), specificity(%) and diagnostic accuracy(%) of each scan. RESULT : The results of each scan were 85.7, 100, 100, 85, 92.1% in Tl-201, 81, 94.1, 94.4, 80, 86.8% in Tc-99m-MIBI and 50, 66.7, 88.9, 20, 52.6% in Tc-99m-MDP scan. As a conclusion, Tl-201 scan was the most specific and accurate method for detecting malignant tumor tissue. Tc-99m-MIBI scan was also good for malignant tumor searching. CONCLUSION : With our results, we can use Tl-201 scan to differentiate benign from malignant tumor, and to evaluate the response of preoperative chemotherapy or radiotherapy, and to determine the residual tumor or local recurrence. For the better result, we need to have a more detail information about false positive cases and a more objective and quantitative reading technique.

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회귀방법에 의한 초음파 진단기의 측면해상도 개선에 관한 연구 (A recursive scheme for improvement of the lateral resolution in B-scan ultrasonography)

  • 김선일;민병구;고명삼
    • 전기의세계
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    • 제31권3호
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    • pp.204-208
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    • 1982
  • The objective of this paper is to present a digital method for improving the lateral resolution of the B-scan images in the medical applications of ultrasound. The method is based upon a mathematical model of the lateral blurring caused by the finite beam width of the transducers. This model provides a simple method of applying a recursive scheme for image restoration with fast computation time. The point spread function (P.S.F.) can be measured by the reflective signals after scanning the small pins located along the depth of interest. From the measured P.S.F., one can compute the coefficient matrices of the inverse discrete-time dynamic state variable equation of the blurring process. Then, a recursive scheme for deblurring is applied to the recorded B-scan to improve the lateral resolution. One major advantage of the present recursive scheme over the transform method is in its applicability for the space-variant imaging, such as in the case of the rotational movement of transducer.

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스캔라인 영상분할기법에 의한 정밀도 측정에 관한 연구 (Precision Measurement using Scan-line image Segmentation Method)

  • 박정수;윤재웅;정원
    • 한국산업정보학회논문지
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    • 제7권4호
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    • pp.29-36
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    • 2002
  • 본 연구에서는 영상분할기법을 이용한 스캔라인기법에 기초하여 영역 이미지의 새로운 에지 결합방식을 제시한다. 본 논문에서 제시한 기존 알고리즘은 3차원 영상을 2차원 영상으로 적용하는 과정에서 깊이의 정보, 조명등의 영향으로 심한 잡음이 발생하여 이로 인해 정밀측정에 많은 어려움이 있었다. 기존의 스캔라인기법은 광원에 의해 직선추출의 형상인식에서만 활용하였으나 이를 원호에 적용 정밀측정 하였다. 본 연구로 인한 오프라인(Off-line)의 검사방식을 온라인(On-line) 방식에서도 정밀측정이 가능함을 입증하였다.

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3D 스캔 데이터를 활용한 밀착 패턴원형 개발 (Development of 2D Tight-fitting Pattern from 3D Scan Data)

  • 정연희;홍경희
    • 한국의류학회지
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    • 제30권1호
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    • pp.157-166
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    • 2006
  • The human body, which is composed of concave and convex curvatures, makes it difficult to transfer into 2D patterns directly from 3D data. In previous studies. Jeong, et al.(2004) suggested the block method was fester and easier when dealing with the triangular patches of male's upper dress form. Although the block method is useful to make a pattern, the information(area, length, etc.) from a 2D pattern would be different depending on the direction of the block method. As a result horizontal and diagonal block methods were suggested as optimal methods for 2D tight-fitting patterns. These block methods were closer to the original area of the 3D scan data than the vertical block method. The total area of the 2D pattern obtained by the horizontal and diagonal block methods showed little differences. In case of the horizontal and diagonal block methods, the total error of the 2D pattern area ranged from $0.01\%\~0.25\%$. In comparing the length of the 2D pattern with that of the 3D scan data, the obtained 2D pattern was $0.1\~0.2cm$ shorter than the 3D scan data, which was within the acceptable range of errors in making clothes. 3D space distribution images between the body surface and the experimental clothing were also measured and $3\%$ enlargement of the original pattern was verified as the adequate adjustment.

CareDose 4D 사용 시 동일한 스캔조건에서 조직기반설정을 다르게 적용함에 따른 선량 비교: 성인과 소아팬텀 연구 (Radiation Dose Comparison according to Different Organ Characteristics at Same Scan Parameters Using CareDose 4D: An Adult and Pediatric Phantom Evaluation)

  • 공효금;이기백
    • 대한방사선기술학회지:방사선기술과학
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    • 제42권4호
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    • pp.271-277
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    • 2019
  • CareDose 4D which is the Siemens's Automatic Exposure Control (AEC) can adjust the level of radiation dose distribution which is based on organ characteristic unlike other manufacturer's AEC. Currently, a wide scan range containing different organs is sometimes examined at once (defined as one scan). The purpose of this study was to figure out which organ characteristic option is suitable when one scan method is utilized. Two types of anthropomorphic phantoms were scanned in the same range which were from frontal bone to carina level according to three different organ characteristics such as Thorax, Abdomen, and Neck. All scans and image reconstruction parameters were equally applied and radiation dose were compared. Radiation dose with Thorax organ characteristic was lower than that with Neck. Also, that with Abdomen oran characteristic was lower than Thorax. There were significant differences in radiation dose according to different organ characteristics at the same parameters (P<0.05). Usage of Neck organ characteristic had a result of the highest radiation dose to all phantom. On the other hand, utilization of Abdomen organ characteristic showed the lowest radiation dose. As a result, it is desirable to set appropriate organ characteristic according to examined body part when you checkup patients. Also, when you implement one scan method, selection of Abdomen-based organ characteristic has reduced more radiation dose compared with two different organ characteristic.

고속 라인 스캔 방식을 이용한 CFRP 가공 홀 표면 및 내부 결함 검사 (Measurements of Defects after Machining CFRP Holes Using High Speed Line Scan)

  • 김택겸;경대수;손운철;박선영
    • 한국정밀공학회지
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    • 제33권6호
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    • pp.459-467
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    • 2016
  • Using a line scan camera and a Galvano mirror, we constructed a high-speed line-scanning microscope that can generate 2D images ($8000{\times}8000pixels$) without any moving parts. The line scanner consists of a Galvano mirror and a cylindrical lens, which creates a line focus that sweeps over the sample. The measured resolutions in the x (perpendicular to line focus) and y (parallel to line focus) directions are both $2{\mu}m$, with a 2X scan lens and a 3X relay lens. This optical system is useful for measuring defects, such as spalling, chipping, delamination, etc., on the surface of carbon fiber reinforced plastic (CFRP) holes after machining in conjunction with adjustments in the angle of LED lighting. Defects on the inner wall of holes are measured by line confocal laser scanning. This confocal method will be useful for analyzing defects after CFRP machining and for fast 3D image reconstruction.

흉곽부위 골절에 대한 골스캔의 유용성 고찰 (Availability of Bone Scan in Chest Trauma Patients)

    • Journal of Chest Surgery
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    • 제31권11호
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    • pp.1085-1088
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    • 1998
  • 연구배경 : 많은 외상 환자에서 흉곽골이 손상에 노출되지만 흉곽골 외상 환자에서 단순 흉부 사진으로 흉곽부위 손상정도를 최종진단 하기는 어려운 경우가 많다. 특별히 흉곽골의 경미한 손상의 경우는 골주사 검사를 사용하여 명확한 진단을 할 수 있겠는데 감수성은 매우 높은 결과를 나타내었다. 재료 및 방법 : 680명의 흉곽 외상환자 중 골스캔을 환자를 대상으로 조사하였다. 결과 : 680례에서 감수성은 97.4%이고 위음성은 2.6%였다. 감수성에 있어서 검사 실시 시기가 가장 중요한 요소로 생각되며 손상 부위별로 늑골이나 흉골 골절의 경우는 1주 이후, 늑연골 접합부골절의 경우와 상기 부위골절들이 동반된 경우는 3일 이후면 언제나 우수한 결과를 보였다. 결론 : 흉부외상환자에서 골절에 대한 정확한 진단을 위하여는 적절한 시기의 골스캔이 필요하다.

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