• Title/Summary/Keyword: Scan conversion

Search Result 83, Processing Time 0.03 seconds

We Nuclear Physicians might have used the Term 'Activity' of Pulmonary Tuberculosis differently from Clinicians Who Treat Patients with Tuberculosis (폐결핵의 활동성 판정에 $^{99m}Tc$-MIBI 스캔을 이용할 때 있어서 용어상의 오해)

  • Park, Seok-Gun;Park, Jae-Seuk
    • The Korean Journal of Nuclear Medicine
    • /
    • v.34 no.2
    • /
    • pp.129-134
    • /
    • 2000
  • Purpose: It is difficult to determine the activity of tuberculosis radiologically. Therefore there have been efforts to assess the activity using radiopharmaceuticals such as $^{67}Ga,\;^{99m}Tc-tetrofosmin,\;and\;^{99m}Tc-MIBI$. But there may be some discrepancy in defining the term 'activity' between clinicians and nuclear physicians. While negative conversion of sputum acid fast bacilli (AFB) is defined as 'disappearance of activity' by clinicians, a loss of uptake in previously positive lesion is accepted as 'disappearance of activity' by nuclear physicians. We designed a prospective study to see if the negative conversion of sputum AFB could directly match the disappearance of radioactivity of the lesion. Materials and Methods: Fifteen patients with bacteriologically confirmed active localized pulmonary tuberculosis were scanned 10 and 60 min after intravenous injection of 550 MBq $^{99m}Tc$-MIBI. In 6 patients, who showed negative conversion of sputum AFB after 3-7 months of chemotherapy, $^{99m}Tc$-MIBI scan was repeated. For the purpose of comparison, target/nontarget ratios of the lesions were determined. Results: 12/15 (80%) patients with active pulmonary tuberculosis showed increased uptake of $^{99m}Tc$-MIBI in tuberculous lesion. After negative conversion of sputum AFB, 5/6 (83%) patients still showed increased uptake, although the intensity of uptake decreased. Conclusion: Uptake of radioactivity decreased but did not disappear after negative conversion of sputum AFB. $^{99m}Tc$-MIBI scan may be useful to address the degree of inflammation of pulmonary tuberculous lesion, but the uptake did not directly match the activity defined by positivity of sputum AFB. We nuclear physicians might have used the term 'activity' somewhat differently from clinicians who treat patients with tuberculosis.

  • PDF

Material Characterization of Weld-Zone Using Poisson's Ratio Distribution

  • Park, Jin-Ha;Kim, Young-H.;Lee, Seung-S.;Kim, Young-Gil
    • Journal of the Korean Society for Nondestructive Testing
    • /
    • v.29 no.6
    • /
    • pp.586-590
    • /
    • 2009
  • Poisson's ratio, one of elastic constants of elastic solids, has not attracted attention due to its narrow range and difficult measurement. Transverse wave velocity as well as longitudinal wave velocity should be measured for nondestructive measurement of Poisson's ratio. Rigid couplants for transverse wave is one of obstacle for scanning over specimen. In the present work, a novel measurement of Poisson's ratio distribution was applied. Immersion method was employed for the scanning over the specimen. Echo signals of normal beam longitudinal wave were collected, and transverse wave modes generated by mode conversion were identified. From transit time of longitudinal and transverse waves, Poisson's ratio was determined without the information of specimen thickness. Poisson's ratio distribution of the carbon steel weldment was mapped. Heat affected zone of the weldment was clearly distinguished from base and filler metals.

3D Deinterlacing Algorithm Based on Wide Sparse Vector Correlations

  • Kim, Yeong-Taeg
    • Journal of Broadcast Engineering
    • /
    • v.1 no.1
    • /
    • pp.44-54
    • /
    • 1996
  • In this paper, we propose a new 3-D deinterlacing algorithm based on wide sparse vector correlations and a vertical edge based motion detection algorithm. which is an extension of the deinterlacing algorithm proposed in [10. llJ by the authors. The prooised algorithm is developed mainly for the format conversion problem encountered in current HDTV system, but can also be aplicable to the double scan conversion problesm frequently encountered in ths NTSC systems. By exploiting the edge oriented spatial interpolation based on the wide vector correlations, visually annoying artifiacts caused by interlacing such as a serrate line. line crawling, a line flicker, and a large area flicker can be remarkably reduced since the use of the wide vectors increases the range of the edge orientations that can be detected, and by exploiting sparse vectors correlations the HjW complexity for realizing the algorithm in applications cam be significantly simplified. Simulations are provided indicating thet the proposed algorithm results in a high performance comparable to the performance of the deinterlacing algorithm. based on the wide vector correlations.

  • PDF

DNC Application of Car Fuel Tank Die Working (자동차 연료탱크 금형가공을 위한 DNC 활용)

  • 이종선
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
    • /
    • 1999.10a
    • /
    • pp.269-274
    • /
    • 1999
  • This paper aims to DNC application of car fuel tank die working. DNC system is consist of CAD, CAM software and CNC milling machine. CAM software is purpose to G-code generation for CNC programming. Then CAM software and CNC milling machine are connect to RS-232-C cable for networking.

  • PDF

Doses of Coronary Study in 64 Channel Multi-Detector Computed Tomography : Reduced Radiation Dose According to Varity of Examnination Protocols (64 채널 Multi-Detector Computed Tomography를 이용한 관상동맥검사의 선량 : 검사 프로토콜 다변화에 따른 환자선량 감소)

  • Kim, Moon-Chan
    • Journal of radiological science and technology
    • /
    • v.32 no.3
    • /
    • pp.299-306
    • /
    • 2009
  • Purpose : To compare radiation dose for coronary CT angiography (CTA) obtained with 6 examination protocols such as a retrospectively ECG gated helical scan, a prospectively ECG gated sequential scan, low kVp technique, and cardiac dose modulation technique. Materials and Methods : Coronary CTA was performed by using 6 current clinical protocols to evaluate effective dose and organ dose in primary beam area with anthropomorphic female phantom and glass dosimetric system in 64 channel multi-detector CT. After acquiring topograms of frontal and lateral projection with 80 kVp and 10 mA, main coronary scan was done with 0.35 sec tube rotation time, 40 mm collimation ($0.625\;mm{\times}64\;ea$), small scan field of view (32 cm diameter), 105 mm scan length. Heart beat rate of phantom was maintained 60 bpm in ECG gating. In constant mAs technique 120 kVp, 600 mA was used, and 100 kVp for low kVp technique. In a retrospectively ECG gated helical CT technique 0.22 pitch was used, peak mA (600 mA) was adopted in range of $40{\sim}80%$ of R-R interval and 120mA(80% reduction) in others with cardiac dose modulation. And 210 mAs was used without cardiac dose modulation. In a prospectively ECG gated sequential CT technique data were acquired at 75% R-R interval (middle diastolic phase in cardiac cycle), and 120 msec additional padding of the tube-on time was used. For effective dose calculation region specific conversion factor of dose length product in thorax was used, which was recommended by EUR 16262. Results : The mean effective dose for conventional coronary CTA without cardiac dose modulation in a retrospectively ECG gated helical scan was 17.8 mSv, and mean organ dose of heart was 103.8 mGy. With low kVp and cardiac dose modulation the mean effective dose showed 54.5% reduction, and heart dose showed 52.3% reduction, compared with that of conventional coronary CTA. And at the sequential scan(SnapShot pulse mode) under prospective ECG gating the mean effective dose was 4.9 mSv, this represents an 72.5% reduction compared with that of conventional coronary CTA. And heart dose was 33.8 mGy, this represents 67.4% reduction. In the sequential scan technique under prospective ECG gating with low kVp the mean effective dose was 3.0 mSv, this represents an 83.2% reduction compared with that of conventional coronary CTA. And heart dose was 17.7 mGy, this represents an 82.9% reduction. Conclusion : In coronary CTA at retrospectively ECG gated helical scan, cardiac dose modulation technique using low kVp reduced dose to 50% above compared with the conventional helical scan. And the prospectively ECG gated sequential scan offers substantially reduced dose compared with the traditional retrospectively ECG gated helical scan.

  • PDF

An Efficient Deinterlacing Algorithm Using New Edge-Directed Interpolation (새로운 에지 방향 보간법을 이용한 효율적인 디인터레이싱 알고리듬)

  • Kim, Min-Ki;Jeong, Je-Chang
    • Journal of Broadcast Engineering
    • /
    • v.12 no.2
    • /
    • pp.185-192
    • /
    • 2007
  • The interpolation is used in many image processing applications such as image enhancement, de-interlacing/scan-rate conversion, wavelet transforms based on the lifting scheme, and so on. Among these, de-interlacing and scan-rate conversion are proposed for the digital TV applications. The de-interlacing algorithm can be classified into two categories. The first one uses only one field, called intra-field de-interlacing, and the other uses multiple field, called inter-field de-interlacing. In this paper, an efficient de-interlacing algorithm using spatial domain information is proposed far the interpolation of interlaced images. By efficiently estimating the directional correlations, improved interpolation accuracy has been achieved. In addition, the proposed method is simply structured and is easy to implement. Extensive simulations conducted for various images and video sequences have shown the efficacy of the proposed method with significant improvement over the previous intra-field do-interlacing methods in terms of the objective image quality as well as the subjective image quality.

Thermodynamic Analysis of the Low- to Physiological-Temperature Nondenaturational Conformational Change of Bovine Carbonic Anhydrase

  • Hollowell, Heather N.;Younvanich, Saronya S.;McNevin, Stacey L.;Britt, B. Mark
    • BMB Reports
    • /
    • v.40 no.2
    • /
    • pp.205-211
    • /
    • 2007
  • The stability curve - a plot of the Gibbs free energy of unfolding versus temperature - is calculated for bovine erythrocyte carbonic anhydrase in 150 mM sodium phosphate (pH = 7.0) from a combination of reversible differential scanning calorimetry measurements and isothermal guanidine hydrochloride titrations. The enzyme possesses two stable folded conformers with the conformational transition occurring at ~30$^{\circ}C$. The methodology yields a stability curve for the complete unfolding of the enzyme below this temperature but only the partial unfolding, to the molten globule state, above it. The transition state thermodynamics for the low- to physiological-temperature conformational change are calculated from slow-scan-rate differential scanning calorimetry measurements where it is found that the free energy barrier for the conversion is 90 kJ/mole and the transition state possesses a substantial unfolding quality. The data therefore suggest that the x-ray structure may differ considerably from the physiological structure and that the two conformers are not readily interconverted.

Unit-Rectangle Exposure Method for Advanced Through-put in Electron-Beam Direct Writing Lithography (전자선 직접묘사에서 Through-put이 향상된 단위 矩形묘사방법)

  • Park, Sun-Woo;Kim, Chul-Ju
    • Journal of the Korean Institute of Telematics and Electronics
    • /
    • v.26 no.2
    • /
    • pp.112-117
    • /
    • 1989
  • This paper describes to the unit rectangle EB direct writing lithography method using SEM. This method has the constant exposure time to any rectangle pattern. In order to change the EB current according to various rectangle size for the constant exposure time, the supply current of condenser lens in controlled by BITMAP-IV CAD system. By this method, the resizing procedure of density pattern area is not needed to pattern data conversion, and the through-put ofr exposure is increased about 172 times compared with the unit scan exposure method.

  • PDF

2D Lower Body Flat Pattern of the Women in Their Twenties Using 3D Scan Data (3차원 인체 형상을 이용한 20대 여성의 하반신 전개패턴에 관한 연구)

  • Yoon, Mi-Kyung;Nam, Yun-Ja;Choi, Kyeng-Mi
    • Journal of the Korean Society of Clothing and Textiles
    • /
    • v.31 no.5 s.164
    • /
    • pp.692-704
    • /
    • 2007
  • Recently, Basic patterns with excellent body fitness and automation availability are required to be developed in order to automate the patterns of women's clothes. In this study, this reference points, reference lines and segments were fixed onto 3D scan data for the lower body the women in their twenties, they were directly spread out to be 2D flat pattern to facilitate development into the design of slacks adhered closely to the human body such as special and highly-functional clothes, and then slacks 2D pattern was developed for the purpose of seeking scientific approach to the development into basic form slacks and 3d emotional pattern. For conversion of 3D pattern into 2D flat pattern, reference points and segments were created by using Rapid Form of 3D shape analysis software, and triangle mesh of the body surface of the created shape was developed with Auto CAD 2005. The correspondence between slacks and human body was examined by the fixation of major reference lines. Specially, the wearing characteristics of slacks were considered by the fixation of side lines in consideration of posture. As a result of using the way of development to constantly maintain the length while 3D triangle mesh is converted into 2D flat mesh, the shape was shown to be excellently reproduced, and the area of flat pattern was increased compared to the shape of parting plane. Also, the sunk-in curve like the brief line of front crotch length needed a cutting line when it was closely adhered, when mesh was overlapped, and the pattern area was smaller compared to the actual shape.

System Strategies for Time-Domain Emission Measurements above 1 GHz

  • Hoffmann, Christian;Slim, Hassan Hani;Russer, Peter
    • Journal of electromagnetic engineering and science
    • /
    • v.11 no.4
    • /
    • pp.304-310
    • /
    • 2011
  • The application of time-domain methods in emission measurement instruments allows for a reduction in scan time by several orders of magnitude and for new evaluation methods to be realized such as the real-time spectrogram to characterize transient emissions. In this paper two novel systems for time-domain EMI measurements above 1 GHz are presented. The first system combines ultra-fast analog-to-digital-conversion and real-time digital signal processing on a field-programmable-gate-array (FPGA) with ultra-broadband multi-stage down-conversion to enable measurements in the range from 10 Hz to 26 GHz with high sensitivity and full-compliance with the requirements of CISPR 16-1-1. The required IF bandwidths were added to allow for measurements according to MIL-461F and DO-160F. The second system realizes a system of time-interleaved analog-to-digital converters (ADCs) and has an upper bandwidth limit of 4 GHz. With the implementation of an automatic mismatch calibration, the system fulfills CISPR 16-1-1 dynamic range requirements. Measurements of the radiated emissions of electronic consumer devices and household appliances like the non-stationary emissions of a microwave oven are presented. A measurement of a personal computer's conducted emissions on a power supply line according to DO-160F is given.