• 제목/요약/키워드: diagnostic test

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X선관의 실효초점 측정에 관한 고찰 (Measurement of Focal Spot Size of Heavy Loaded X-ray Tubes)

  • 장광현;임오수;김형기;송창욱;정경모;정환
    • 대한방사선기술학회지:방사선기술과학
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    • 제16권1호
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    • pp.101-106
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    • 1993
  • In order to assure safety of both patient and operator, and to provide uniform quality radiographs, it is necessary to perform periodic calibration of diagnostic X-ray equipment. A basic parameter of diagnostic equipment's and its image sharpness is the size(and shape the energy distribution) of the focal spot as viewed along the central X-ray beam. This size determines the resolution possible with the equipment and also determines the heat characteristics of an anode. A fine focus tube gives high resolution but causes high local heating of target. In past, the pin-hole and star pattern image measurement for evaluation of resolution have been widely used, but it produced blurring and inaccuracy of image. So newly inverted Ug-meter has advantage in more convenient measurement method and less out-put bias than other image measurement. The authors intended to compare measured focal size between Ug-meter and focal spot test tool, changed state from setting to now of units.

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모바일 환경에서 의료 진단 정보 시스템의 구현 및 의료 영상의 적합성 평가 (Implementation of Medical Diagnostic Information System and Conformance Test of Medical Image in Mobile Environment)

  • 조정호;김광현
    • 한국전자통신학회논문지
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    • 제10권6호
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    • pp.713-720
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    • 2015
  • 모바일 환경이 널리 확산되면서 최근 의료진단시스템은 기존 시스템의 지역적 한계를 넘어 시공간의 제약을 받지 않고 제공되고 있다. 또한 무선 인터넷 기술과 모바일 이동 통신 기술이 의료 기술과 융합하며 빠르게 보급되어 발전하고 있다. 의료 서비스 이용자는 다양한 종류의 무선 단말기를 이용하여 이동 중 무선망을 통해 의료 서비스를 제공 받을 수 있다. 본 논문에서는 병원 의료영상 진단 정보를 병원내의 시공간을 벗어나 전송, 검색 및 갱신할 수 있는 의료 진단 정보 시스템을 구현하고 평가하였다. DICOM CT영상과 JPEG 2000 CT압축영상의 비교를 통하여 임상적으로 적합한 영상인지를 t-test를 실시하여 통계적으로 평가한 결과 DICOM CT영상의 경우 평균 평가 값이 비교적 임상적 진단에 적합한 영상임을 확인하였다.

Clinicopathological Significance and Diagnostic Accuracy of c-MET Expression by Immunohistochemistry in Gastric Cancer: A Meta-Analysis

  • Pyo, Jung-Soo;Kang, Guhyun;Cho, Hyunjin
    • Journal of Gastric Cancer
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    • 제16권3호
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    • pp.141-151
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    • 2016
  • Purpose: The aim of the present study was to elucidate the clinicopathological significance and diagnostic accuracy of immunohistochemistry (IHC) for determining the mesenchymal epidermal transition (c-MET) expression in patients with gastric cancer (GC). Materials and Methods: The present meta-analysis investigated the correlation between c-MET expression as determined by IHC and the clinicopathological parameters in 8,395 GC patients from 37 studies that satisfied the eligibility criteria. In addition, a concordance analysis was performed between c-MET expression as determined by IHC and c-MET amplification, and the diagnostic test accuracy was reviewed. Results: The estimated rate of c-MET overexpression was 0.403 (95% confidence interval [CI], 0.327~0.484) and it was significantly correlated with male patients, poor differentiation, lymph node metastasis, higher TNM stage, and human epidermal growth factor receptor 2 (HER2) positivity in IHC analysis. There was a significant correlation between c-MET expression and worse overall survival rate (hazard ratio, 1.588; 95% CI, 1.266~1.992). The concordance rates between c-MET expression and c-MET amplification were 0.967 (95% CI, 0.916~0.987) and 0.270 (95% CI, 0.173~0.395) for cases with non-overexpressed and overexpressed c-MET, respectively. In the diagnostic test accuracy review, the pooled sensitivity and specificity were 0.56 (95% CI, 0.50~0.63) and 0.79 (95% CI, 0.77~0.81), respectively. Conclusions: The c-MET overexpression as determined by IHC was significantly correlated with aggressive tumor behavior and positive IHC status for HER2 in patients with GC. In addition, the c-MET expression status could be useful in the screening of c-MET amplification in patients with GC.

Development and Validation of Generalized Linear Regression Models to Predict Vessel Enhancement on Coronary CT Angiography

  • Masuda, Takanori;Nakaura, Takeshi;Funama, Yoshinori;Sato, Tomoyasu;Higaki, Toru;Kiguchi, Masao;Matsumoto, Yoriaki;Yamashita, Yukari;Imada, Naoyuki;Awai, Kazuo
    • Korean Journal of Radiology
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    • 제19권6호
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    • pp.1021-1030
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    • 2018
  • Objective: We evaluated the effect of various patient characteristics and time-density curve (TDC)-factors on the test bolus-affected vessel enhancement on coronary computed tomography angiography (CCTA). We also assessed the value of generalized linear regression models (GLMs) for predicting enhancement on CCTA. Materials and Methods: We performed univariate and multivariate regression analysis to evaluate the effect of patient characteristics and to compare contrast enhancement per gram of iodine on test bolus (${\Delta}HUTEST$) and CCTA (${\Delta}HUCCTA$). We developed GLMs to predict ${\Delta}HUCCTA$. GLMs including independent variables were validated with 6-fold cross-validation using the correlation coefficient and Bland-Altman analysis. Results: In multivariate analysis, only total body weight (TBW) and ${\Delta}HUTEST$ maintained their independent predictive value (p < 0.001). In validation analysis, the highest correlation coefficient between ${\Delta}HUCCTA$ and the prediction values was seen in the GLM (r = 0.75), followed by TDC (r = 0.69) and TBW (r = 0.62). The lowest Bland-Altman limit of agreement was observed with GLM-3 (mean difference, $-0.0{\pm}5.1$ Hounsfield units/grams of iodine [HU/gI]; 95% confidence interval [CI], -10.1, 10.1), followed by ${\Delta}HUCCTA$ ($-0.0{\pm}5.9HU/gI$; 95% CI, -11.9, 11.9) and TBW ($1.1{\pm}6.2HU/gI$; 95% CI, -11.2, 13.4). Conclusion: We demonstrated that the patient's TBW and ${\Delta}HUTEST$ significantly affected contrast enhancement on CCTA images and that the combined use of clinical information and test bolus results is useful for predicting aortic enhancement.

초중등학생 정보 교과 역량 검사 도구 개발 (Development of Information Competency Test Tool for Elementary and High School Students)

  • 홍지연;박정호
    • 한국정보통신학회논문지
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    • 제26권4호
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    • pp.605-611
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    • 2022
  • 4차 산업 혁명의 영향으로 미래 사회에 대비한 인재를 육성하기 위해 컴퓨팅 사고력을 기반으로 하는 역량 증진이 지속적으로 강조되고 있고 이에 우리나라에서도 2018년부터 SW교육을 의무로 실시하고 있다. 이에 따라 2017년부터 SW교육 역량 정의 및 진단 도구개발에 관한 연구가 진행되었으며 이때 개발된 중학생용 진단 도구를 2018년 한차례 수정 보완하여 지금까지 사용하고 있다. 이에 중학생만을 대상으로 하는 정보 교과 역량 검사를 초등학생과 고등학생을 대상까지 확대하고자 하는 현장의 요청에 의해 2019년 SW교육 선도학교 효과성 연구의 하나로 본 연구가 시작되었다. 본 연구에서는 중학생용 진단 도구를 기준으로 초등학생과 고등학생을 위한 진단 도구를 개발하고, 전문가 타당도 검증 및 예비검사를 실시한다. 예비검사를 통해 문항의 신뢰도, 변별도, 난이도 등을 분석하여 향후 초등학생과 고등학생을 대상으로 하는 검사 도구로서 가능성을 살펴볼 수 있을 것으로 기대한다.

고압전동기 절연진단 해석(I) (Analysis of Insulation Diagnostic Test for High Voltage Motor(I))

  • 이영준;주영호
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1999년도 하계학술대회 논문집 E
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    • pp.2104-2106
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    • 1999
  • The insulation diagnostic tests was performed at local thermal power plants high voltage motor. The insulation diagnostic tests include measurements of insulation resistance, polarization index, AC current, $tan{\delta}$, partial discharges. This paper describes the difference of insulation characteristics for high voltage motor makers.

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PL대응시스템 진단기법 (On the Diagnostic Methods for the Product Liability Management System)

  • 김종걸;빈성욱
    • 대한안전경영과학회:학술대회논문집
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    • 대한안전경영과학회 2004년도 춘계학술대회
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    • pp.153-159
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    • 2004
  • There are various types of PLM(product liability management) according to corporation management level. It is necessary to develop diagnostic methods and application systems for PLM as well as to establish an efficient PLM system. This paper aims to propose a PLM system which can be applied to product with high-reliability and high-safety, and diagnostic methods for PLM based on AHP, and also show an empirical application of the proposed PL management system for Auto Test Robot System of the Mobile Phone (EVT 4320).

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A Flexible Programmable Memory BIST for Embedded Single-Port Memory and Dual-Port Memory

  • Park, Youngkyu;Kim, Hong-Sik;Choi, Inhyuk;Kang, Sungho
    • ETRI Journal
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    • 제35권5호
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    • pp.808-818
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    • 2013
  • Programmable memory built-in self-test (PMBIST) is an attractive approach for testing embedded memory. However, the main difficulties of the previous works are the large area overhead and low flexibility. To overcome these problems, a new flexible PMBIST (FPMBIST) architecture that can test both single-port memory and dual-port memory using various test algorithms is proposed. In the FPMBIST, a new instruction set is developed to minimize the FPMBIST area overhead and to maximize the flexibility. In addition, FPMBIST includes a diagnostic scheme that can improve the yield by supporting three types of diagnostic methods for repair and diagnosis. The experiment results show that the proposed FPMBIST has small area overhead despite the fact that it supports various test algorithms, thus having high flexibility.

고압회전기 절연열화진단의 현장적용기술연구 (A Study on Site Application Techniques for Insulation Reliability of Rotating Machine)

  • 김길용;조경해;김택수;한상욱;이현수
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1991년도 하계학술대회 논문집
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    • pp.286-291
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    • 1991
  • Most of the failures of rotating machine are stator coil insulation failures. The insulation diagnostic testing for high voltage motors and generators are only megger test and P. I Test which is applied DC voltage until now. But it was impossible to judge insulation deterioration status of high voltage rotating machinery by above testing. In other words, even though the megger measurement values are fairly high, they used to be failed from time to time. Therefore in order to excute reliable and detailed diagnosis of insulation deterioration for rotating machinery, the tangent delta test, the alternating current test and the partial discharge test shall be applied to the insulation diagnostic testing on site.

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