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Article
Publication date: 1 June 1998

Jinung An

X‐ray laminography, a tomographic technique that can examine individual planes of focus within a 3‐D structure, promises to be an excellent method of inspecting…

Abstract

X‐ray laminography, a tomographic technique that can examine individual planes of focus within a 3‐D structure, promises to be an excellent method of inspecting complicated circuit boards. The technique has accuracy appropriate for circuit board inspection, but the application has been limited by the requirements of synchronized motion of the source and detector, a sophisticated X‐ray device and a huge image acquiring system. A new translational laminography system is presented. The X‐ray source and detector described are stationary. Translation of the XY table is only the mechanical motion required to generate the laminographic image. Based on this system, a new image separation algorithm is also explained. This algorithm uses a recursive process with a simple mathematical function, which is derived analytically by the X‐ray projection geometry. To evaluate the proposed method, an X‐ray imaging system has been constructed. From the test sample experiments, it is confirmed that the proposed algorithm allows cleanly separated images with fewer artifacts than the one obtained by conventional laminography.

Details

Circuit World, vol. 24 no. 2
Type: Research Article
ISSN: 0305-6120

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Article
Publication date: 27 June 2008

Christine Connolly

The purpose of this paper is to present improvements in X‐ray equipment, which are leading to wider use.

Abstract

Purpose

The purpose of this paper is to present improvements in X‐ray equipment, which are leading to wider use.

Design/methodology/approach

Developments in X‐ray sources and detectors are described. This is followed by a review of the more innovative equipment available for security and industrial applications.

Findings

Technological developments have produced smaller, lighter X‐ray systems and extended their applications to on‐site work. Multiple wavelength systems distinguish between different materials, and stereo systems remove ambiguities from X‐ray security imaging and allow 3D gauging of industrial components.

Originality/value

The paper highlights the availability of portable X‐ray systems and explains the underlying technology.

Details

Sensor Review, vol. 28 no. 3
Type: Research Article
ISSN: 0260-2288

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Article
Publication date: 22 August 2008

C.A. Smith

The aim is to focus on the application of X‐rays in the failure analysis of electronic devices and systems, with an emphasis on X‐ray radiography and X‐ray spectroscopy.

Abstract

Purpose

The aim is to focus on the application of X‐rays in the failure analysis of electronic devices and systems, with an emphasis on X‐ray radiography and X‐ray spectroscopy.

Design/methodology/approach

The theory behind X‐ray radiography and X‐ray spectroscopy is reviewed, and relevant case studies are used to illustrate the application of these techniques in the failure analysis of electronic devices and systems.

Findings

Examples from recent case studies are given.

Originality/value

The paper provides an introduction to X‐ray methods for engineers working on the failure analysis of electronic devices and systems who may be unfamiliar with these techniques.

Details

Circuit World, vol. 34 no. 3
Type: Research Article
ISSN: 0305-6120

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Article
Publication date: 12 April 2011

István Latos and Mihály Janóczki

The purpose of this paper is to develop a new method of evaluating the present state of X‐ray machines used in the electronics device manufacturing industry.

Abstract

Purpose

The purpose of this paper is to develop a new method of evaluating the present state of X‐ray machines used in the electronics device manufacturing industry.

Design/methodology/approach

There are several kinds of failures that can only be detected by means of X‐ray inspection. The capabilities and properties of such machines, however, alter over a period of time. The effects of these changes are rarely published and when they are, the significance and reliability of the results produced depends very much on the state and capabilities of the machines in question.

Findings

The effectiveness and appropriateness of the present methods of calibration have been investigated. The optimization of the prevalence and effectiveness of these calibrations is described. Suggestions are also made as to the necessary adjustments or repairs that are required to reach the ideal optimized state of X‐ray machines. A scientifically substantiated method is also presented that can be efficiently employed in practise during automated X‐ray inspections of electronic devices.

Originality/value

In this paper, a new method of testing automated X‐ray inspection systems is introduced. It is clear that the method currently used by many engineers and inspection system manufacturers is not in itself sufficient, as they do not test grey‐scale and positioning stability in relation to changes that occur over time. Further, there is no evidence that numerical testing of the image quality takes place. Detailed investigations have been carried out to find the best methods to measure these parameters.

Details

Soldering & Surface Mount Technology, vol. 23 no. 2
Type: Research Article
ISSN: 0954-0911

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Article
Publication date: 12 August 2014

Kristina Bliznakova, Zacharias Kamarianakis, Aris Dermitzakis, Zhivko Bliznakov, Ivan Buliev and Nicolas Pallikarakis

The purpose of this paper is to develop a realistic computational model of carbon fibre reinforced polymer (CFRP) structures dedicated for in-silico investigations of the…

Abstract

Purpose

The purpose of this paper is to develop a realistic computational model of carbon fibre reinforced polymer (CFRP) structures dedicated for in-silico investigations of the use of X-ray-based imaging techniques as non-destructive testing (NDT) of CFRP parts.

Design/methodology/approach

CFRPs contain layers of carbon-fibres bundles within resin. Bundles’ orientation in the different layers is arranged with respect to each other at a well-defined primary direction. In the model, the bundle was simulated as a circular cylinder. The resulted model is a stack of layers of unidirectional bundles having orientation of 0°/90°/45°/−45°. Two CFRP structures were modelled: a flat CFRP part and a real shaped CFRP clip. A porous layer and non-carbon fibres were inserted within each model, respectively. X-ray projection images were generated with a dedicated simulation programme. Three setups were investigated: radiography, tomosynthesis and cone-beam CT (CBCT).

Findings

Results showed that porosity and non-carbon fibres were visible with all X-ray-based techniques. Tomosynthesis and CBCT, however, provide higher quality image of defects.

Practical implications

The CFRP computational model is a valuable tool in design, testing and optimization phase of X-ray-based imaging techniques for use in NDT of composite materials. Simulated images are generated within a short time; thus results from virtual optimization and testing are obtained very fast and at low cost.

Originality/value

An innovative computational model of CFRP structures, dedicated for X-ray imaging simulations, has been developed. The model is characterized by simplicity in its creation and realistic visual appearance of the produced X-ray images.

Details

International Journal of Structural Integrity, vol. 5 no. 3
Type: Research Article
ISSN: 1757-9864

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Article
Publication date: 1 March 1995

S. Rooks and T. Sack

To accommodate increasing levels of device integration at the chip level, circuit line densities in electronic packages are continually increasing. Greater circuit line…

Abstract

To accommodate increasing levels of device integration at the chip level, circuit line densities in electronic packages are continually increasing. Greater circuit line density, in turn, necessitates a corresponding increase in package‐to‐board interconnection density, with I/O counts expected to reach over 600 by 1995. In conjunction with the upward trend in I/O counts are a complementary upward trend in clock speed and an opposing downward trend in package sizes driven by the need to provide more functionality in less space, particularly in notebooks and PCMCIA cards. To satisfy the requirements of increased I/O counts and clock speed, and reduced package sizes, various package‐to‐board interconnection technologies are being developed, such as flip chip attach (FCA) using C4 joints. However, FCA interconnections have a disadvantage of being very difficult, if not impossible, to visually inspect. Though automatic test equipment (ATE) can determine whether the package is functional, it cannot determine the quality and reliability of FCA interconnections. Of the possible inspection techniques available to assess the quality of FCA interconnections — differential laser thermal analysis, acoustic microscopy and cross‐sectional X‐ray radiography — only cross‐sectional X‐ray radiography is capable of accurate, automated inspection of production volumes. This paper will first examine the requirements for inspecting FCA joints and will then describe the various inspection alternatives, outlining their advantages and disadvantages. Having described the potential advantage of one particular cross‐sectional X‐ray technique, digital tomosynthesis, the paper will conclude with some cross‐sectional images of FCA and SMT joints taken by a digital tomosynthesis system being developed for the inspection of FCA joints.

Details

Circuit World, vol. 21 no. 3
Type: Research Article
ISSN: 0305-6120

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Article
Publication date: 9 February 2010

Mihály Janóczki and László Jakab

The purpose of this paper is to develop a novel automatic and accurate measurement technique for the volume of solder which is present in solder paste in pin‐in‐paste…

Abstract

Purpose

The purpose of this paper is to develop a novel automatic and accurate measurement technique for the volume of solder which is present in solder paste in pin‐in‐paste (PIP) technology and a calculation algorithm for predicting solder joint quality.

Design/methodology/approach

A new method is described for accurately determining the volume of solder alloy in solder paste that is present in and around the through hole, using X‐ray measurements (orthogonal view X‐ray images, instead of angle view), image processing and other calculations. In addition, various calibration tool constructions are investigated and a method is suggested for determining the calibration curve (for each solder paste) of an X‐ray machine.

Findings

A new calibration tool has been developed to accurately measure the calibration curve of X‐ray machines. Based on several tests, a fast and reliable image processing method for measuring the average grey scale of each pasted through hole is described. Numerous PIP solder joints have been created then analysed using the methodology. To verify the efficiency of the described methods, joints are soldered and inspected using cross‐sectioning and X‐ray imaging.

Originality/value

Calibration curve measurement of an X‐ray machine is done with the help of the developed tool for PIP technology. Orthogonal view X‐ray images are used to measure the volume of printed solder alloy (paste). During the image processing, circle fitting has been simplified to line fitting.

Details

Soldering & Surface Mount Technology, vol. 22 no. 1
Type: Research Article
ISSN: 0954-0911

Keywords

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Article
Publication date: 1 April 1983

T.D.T. Latter

The X‐Ray fluorescence method of coating thickness measurement of ISO 3497, BS 5411 (A), DIN 50987, and ASTM B568–79 is discussed from a practical point of view. A brief…

Abstract

The X‐Ray fluorescence method of coating thickness measurement of ISO 3497, BS 5411 (A), DIN 50987, and ASTM B568–79 is discussed from a practical point of view. A brief illustration of the method's technical principles, advantages, applications, and example instrumentation is given together with some of the precautions to be taken.

Details

Circuit World, vol. 10 no. 1
Type: Research Article
ISSN: 0305-6120

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Article
Publication date: 6 August 2020

Mohammad Khalid Pandit and Shoaib Amin Banday

Novel coronavirus is fast spreading pathogen worldwide and is threatening billions of lives. SARS n-CoV2 is known to affect the lungs of the COVID-19 positive patients…

Abstract

Purpose

Novel coronavirus is fast spreading pathogen worldwide and is threatening billions of lives. SARS n-CoV2 is known to affect the lungs of the COVID-19 positive patients. Chest x-rays are the most widely used imaging technique for clinical diagnosis due to fast imaging time and low cost. The purpose of this study is to use deep learning technique for automatic detection of COVID-19 using chest x-rays.

Design/methodology/approach

The authors used a data set containing confirmed COVID-19 positive, common bacterial pneumonia and healthy cases (no infection). A collection of 1,428 x-ray images is used in this study. The authors used a pre-trained VGG-16 model for the classification task. Transfer learning with fine-tuning was used in this study to effectively train the network on a relatively small chest x-ray data set. Initial experiments show that the model achieves promising results and can be greatly used to expedite COVID-19 detection.

Findings

The authors achieved an accuracy of 96% and 92.5% in two and three output class cases, respectively. Based on these findings, the medical community can access using x-ray images as possible diagnostic tool for faster COVID-19 detection to complement the already testing and diagnosis methods.

Originality/value

The proposed method can be used as initial screening which can help health-care professionals to better treat the COVID patients by timely detecting and screening the presence of disease.

Details

International Journal of Pervasive Computing and Communications, vol. 16 no. 5
Type: Research Article
ISSN: 1742-7371

Keywords

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Article
Publication date: 30 September 2013

Yu-Li Huang

The paper aims to provide a simulation optimization solution to improve patient scheduling that accounts for varying ancillary service time such as x-ray to minimize…

Abstract

Purpose

The paper aims to provide a simulation optimization solution to improve patient scheduling that accounts for varying ancillary service time such as x-ray to minimize patient wait time.

Design/methodology/approach

The two-step approach is to: identify patients' needs for ancillary services while scheduling appointments; and propose an algorithm to determine ancillary service time via simulation optimization. The main aim is to provide sufficient time between arrival at the clinic and the actual examination time for a patient to complete pre-visit activities without contributing significantly to patient wait time. Two case studies are included to demonstrate the approach.

Findings

Triaging at the appointment-scheduling time saves an average 17 minutes for physician's first consultation in a clinic day, and a 7 percent reduction on current average patient wait time for case 1. Case 2 results in a 9 percent reduction on average patient wait time. The scheduled ancillary service time depends on the frequency and the ancillary service time, and appointment slot design.

Research limitations/implications

One limitation is the impact of modeling error on the account of ancillary service times and the modeling assumptions.

Practical implications

The proposed approach provides a studying method for clinic staff to account for ancillary services prior to physicians' visits for a better patient care. Two case studies demonstrated the practicability and promising results on reducing patient waiting.

Originality/value

This article presents a unique approach to considering the required ancillary services in outpatient scheduling system that minimizes patient wait times. The approach will strengthen the existing scheduling methods to allow the time for ancillary services.

Details

International Journal of Health Care Quality Assurance, vol. 26 no. 8
Type: Research Article
ISSN: 0952-6862

Keywords

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