检索结果-南通市图书馆

17th World Conference on Non-Destructive Testing

作者： V.Manoharan Prasad Thapa Rajashekar Venkatachalam G.K.Padmashree Megha Navalgund Debasish Mishra GE Global Research Center 122 EPIPWhite Field Road Bangalore-560 066KarnatakaIndia

＜正＞computed radiography（CR）is gaining importance in industries for inspection of welds and castings using *** is preferred because of lesser exposure time,no chemical processing,lesser cost of consumables and advantage of a digital image *** also allows archiving of digital images over many years,which is mandatory as per ***,Heavy engineering industries,manufactures of high-pressure boilers,Oil ＆ Gas and Energy industries are interested to use computed radiography（CR）for testing weld integrity and corrosion monitoring of process *** applications require radiography to be carried out using radioactive isotopes such as Se-75,Ir-192 and ***,industries do not have enough experience of using CR with *** require information on choosing the right isotope for different range of thicknesses of a material,in order to meet the ASME Section-V *** will also be helpful if there exists data on comparative performance of CR with respect to films on image *** authors have done extensive study at various engineering industries and characterized the performance of CR with *** image quality performances were studied using weld specimens with defects like lack of fusion;penetration,cracks,concavity,and *** paper presents the quantitative metrics used for evaluation of CR specific to standards and comparative study of CR with various film systems.

关键词： computed radiography Isotopes Weld inspection

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

A Derived Exposure Chart for computed radiography in a Negroid Population

引用

Health 2016年第10期8卷 953-958页

作者： Thomas Adejoh Odira C. Ewuzie Joshua K. Ogbonna Stanley O. Nwefuru Nnamdi C. Onuegbu Radiology Department Nnamdi Azikiwe University Teaching Hospital Nnewi Nigeria

Background: computed radiography has a wider exposure latitude when compared with film-screen imaging system. Consequently, the risk of dose creep is high. A conscientious effort is there-fore, needed by the radiographer to keep exposure as low as reasonably achievable. Objective: To derive a computed radiography exposure chart for a negroid population using AGFA photostimulable phosphor plates and a GE static X-ray machine. Materials and Method: A static X-ray machine, a digitizer, and photostimulable phosphor plates were used for the X-ray examination. Chest examinations were done at a Focus-Film-Distance (FFD) of 150 - 180 cm while all other examinations were conducted at 90 - 100 cm FFD. The range of exposure factors (kVp, mA and mAs) used by radiog-raphers in the centre was noted and the 90th percentile calculated. Over a three-month period, the patients were examined with the 90th percentile of tube potential (kVp) while keeping other factors constant. The kVp was gradually decreased and halted if radiologists and radiographers uncon-nected with the work expressed misgivings about the quality of the image. A similar procedure was adopted for the tube current (mA). The threshold adopted as low as reasonably achievable was the factor preceding the point of observation by other personnel. Metrics for central tendency from the statistical packages for social sciences, version 17.0 was used to analyze the data. Results: 335 subjects of both gender aged 0 - 92 years were examined by the researchers. Adult exposure factors used by the radiographers (and those derived by the researchers) had a range of 45 - 130 kVp (62 - 94 kVp), 63 - 320 mA (100 - 250 mA) and 4.0 - 25.0 mAs (5.0 - 20.0 mAs) respectively. Pediatric chest (and researchers-derived) factors were 50 - 75 kVp (52 - 65 kVp), 50 - 250 mA (100 - 220 mA) and 3.20 - 10.0 mAs (3.2 - 6.5 mAs) respectively. Conclusion: Upper threshold of adult (and paediatric) exposure factors in computed radiography with comparab

关键词： computed radiography Exposure Radiographer kVp Tube Current X-Ray

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Strategies for Film Replacement in radiography Films and Digital Detectors in Comparison

Strategies for Film Replacement in Radiography Films and Dig...

引用

17th World Conference on Non-Destructive Testing

作者： Uwe EWERT Uwe ZSCHERPEL Klaus BAVENDIEK Institute for Materials Research and Testing (BAM) D-12200 BerlinGermany YXLON International GmbH D-22419 HamburgGermany

＜正＞The NDT community has discussed about effective film replacement by computed radiography（CR）and the new Digital Detector Arrays（DDA）,also known as flat panel detectors,since more than 10 *** standards were published by CEN,ASTM and ASME to support the application of phosphor imaging plates in lieu of X-ray film in the year *** of the key concepts is the usage of signal/noise（SNR）measurements as equivalent to the optical density of film and film system *** radiographic practice with DDAs is not yet described by any standard,but proposals are under *** first qualification standard for DDAs,ASTM E 2597-07,has been published recently. The bad pixel problem has been *** methods were elaborated and tested at BAM for determination of parameters as basic spatial resolution,efficiency,specific material thickness range,contrast sensitivity and image *** procedures were used for this study. The achieved image quality is discussed for film replacement by CR and DDAs in weld *** strategies for correct DDA calibration yield an extra ordinary increase of image *** contrast sensitivity was enhanced up to 10 times in relation to film *** could not yet be achieved by any other *** restrictions in the spatial resolution,provoked by the individual picture element（pixel）size of the detector,are compensated by the increased contrast sensitivity.

关键词： radiography Film replacement computed radiography Imaging plates Digital detector arrays Contrast sensitivity SNR Standards

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

An Quantitative Evaluation of the Canadian Forces New Radiology Inspection Systems for the Detection of Water Ingress in CF188 Flight Control Surfaces

An Quantitative Evaluation of the Canadian Forces New Radiol...

引用

17th World Conference on Non-Destructive Testing

作者： P.HUNGLER C.P.SWEETAPPLE L.G.I.BENNETT Royal Military College of Canada Department of Chemistry and Chemical EngineeringKingstonOntarioCanada

Canadian Forces(CF)CF188 Hornet aircraft have been plagued with water ingress and related damage in their composite flight control surfaces(FCS). Water ingress can cause structural degradation including corrosion,delamination and disbond. Two different radiology inspection systems were recently acquired by the CF.A new Neutron Radioscopy system and an X-ray computed radiography (CR)system underwent evaluation for detecting water ingress in the composite FCS of the CF188. A Probability of Detection(POD)study revealed that the new neutron radioscopy system has an a90/95 value of 4.65 L for water detection. Furthermore,the X-ray CR system demonstrated sensitivity similar to conventional X-ray film radiography;its a90/95 value for water detection is 20.55 *** image plate from the CR system was also used in conjunction with a conversion screen for neutron radiography and was able to identify water defects in the FCS.

关键词： Neutron radioscopy computed radiography Probability of detection Canada

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：