X-ray Digital Radiography Research Articles

Quantitative Image Quality Metrics of the Low-Dose 2D/3D Slot Scanner Compared to Two Conventional Digital Radiography X-ray Imaging Systems.

The aim of this study was to determine the quantitative image quality metrics of the low-dose 2D/3D EOS slot scanner X-ray imaging system (LDSS) compared with conventional digital radiography (DR) X-ray imaging systems. The effective detective quantum efficiency (eDQE) and effective noise quantum equivalent (eNEQ) were measured using chest and knee protocols. Methods: A Nationwide Evaluation of X-ray Trends (NEXT) of a chest adult phantom and a PolyMethylmethacrylate (PMMA) phantom were used for the chest and knee protocols, respectively. Quantitative image quality metrics, including effective normalised noise power spectrum (eNNPS), effective modulation transfer function (eMTF), eDQE and eNEQ of the LDSS and DR imaging systems were assessed and compared. Results: In the chest acquisition, the LDSS imaging system achieved significantly higher eNEQ and eDQE than the DR imaging systems at lower and higher spatial frequencies (0.001 ≤ p ≤ 0.044). For the knee acquisition, the LDSS imaging system also achieved significantly higher eNEQ and eDQE than the DR imaging systems at lower and higher spatial frequencies (0.001 ≤ p ≤ 0.002). However, there was no significant difference in eNEQ and eDQE between DR systems 1 and 2 at lower and higher spatial frequencies (0.10 < p < 1.00) for either chest or knee protocols. Conclusion: The LDSS imaging system performed well compared to the DR systems. Thus, we have demonstrated that the LDSS imaging system has the potential to be used for clinical diagnostic purposes.

Testing of thickness homogeneity of Si crystal membranes using GaAs Timepix detector

Silicon (Si) membranes were prepared using high precision advance nanomachining technology utilizing single point diamond turning (SPDT). We showed that SPDT allowed to produce membranes with a surface undulation down to 500 nm over diameter of 7800 μm which corresponds to a high accuracy of the surface profile. We used X-ray digital radiography based on absorption contrast for a non-destructive measurement of the thickness distribution within a thin Si crystal membrane. The semi-insulating Gallium Arsenide (SI GaAs) pixel detector bump-bonded to the Timepix readout chip was used as a highly efficient single photon counting X-ray imaging detector. Comparison of thickness values obtained by the SI GaAs Timepix detector with values obtained with a surface stand-type micrometer gauge showed comparable results and the thickness variation within the membrane was clearly detected with a standard deviation down to 8.4 μm. The thickness resolution down to 5 μm over distances of 4–8 mm was achieved in selected areas of the sample.

Experimental and numerical study on progressive damage and failure in composite laminates during open-hole compression tests

Progressive damages in the open-hole compression (OHC) tests of composite laminates were experimentally and numerically studied. In the experiment, the failure mechanisms were investigated via in situ microscopy observation, digital image correlation, X-ray radiography, and X-ray computed tomography. Three layups were tested to examine the dependence of progressive damages on the layups. Additionally, numerical simulation was conducted to comprehensively examine the failure mechanisms. In the numerical studies, the simulation scheme, considering the plasticity, kink-band failure, multiple intra-laminar cracks, and delamination, was developed. From the experiment and simulation, it is clarified that the kink-band is initiated and propagated by the combined stress states consisting of longitudinal compression and in-plane shear around the intra-laminar cracks. Therefore, for the high-fidelity OHC simulation in various layups, it is necessary to capture the interaction between kink-band and intra-laminar cracks by considering the combined stress state in the kink-band failure criteria and modeling the multiple intra-laminar cracks.

Pole-piece position distance identification of cylindrical lithium-ion battery through x-ray testing technology

In the preparation process of cylindrical lithium-ion batteries, a rigorous manufacturing process demands that the position distances between positive and negative pole-pieces must be kept within a reasonable range of variation. Otherwise, a too small position distance may cause safety problems, such as short circuits and thermal runaway. To inspect the position distances between positive and negative pole-pieces automatically, and to decrease the risk of safety and economic losses during the subsequent use, this paper proposes a method to identify the position distance defects of a cylindrical lithium-ion battery on the base of x-ray digital radiography (DR) images. According to this method, the DR image is firstly enhanced by the GPU-accelerated homomorphic filtering algorithm to intensify its contrast and detailed information. Then through the Shi-Tomasi corner detection algorithm, corners of all the positive and negative pole-pieces are preliminarily detected in a region of interest which is defined in advance. To delete the false corners and find the lost corners, one-dimension region growing and curve-fitting methods are adopted. Finally, the minimum position distance, repeated accuracy and alignment metrics are calculated at the base of the detected corners. The experimental results show that the corner positions of five 26 650 cylindrical lithium-ion batteries with different pole-piece structural characteristics can be effectively identified by the proposed method, which provides a useful approach to filtrate unqualified batteries during the process of manufacture.

Layered double hydroxides for controlled fluoride release.

This study aims to develop a nano-sized fluoridated layered double hydroxide (LDH)-based release system via hydrothermal treatment for the controlled delivery of fluoride (F-) ions in the oral environment. The synthesis of conventional LDH-type (C-LDH) precursor nanomaterials was conducted using a co-precipitation method at constant pH, and the nanoparticulate-LDH (N-LDH) was synthesized by a hydrothermal procedure. Fluoride LDH (F-LDH) products were obtained through indirect synthesis using the precursor ion-exchange technique by varying the agitation time (2 and 24 h) and temperature (25 and 40 °C) to produce 12 material samples. The materials were characterized by energy dispersive x-ray, hexamethyldisilazane, digital radiography x-ray, Fourier-transform infrared, thermogravimetric analysis, and scanning electron microscopy. Additionally, the F-release kinetic profile was evaluated for 21 d in neutral and acid media with mathematical model analysis. Products with varying F-quantities were obtained, revealing specific release profiles. In general, there was a higher F-release in the acid medium, with emphasis on F-LDH-8. Fluoride-LDH and controlled fluoride delivery was successfully obtained, proving the potential of these nanomaterials as alternative anti-caries agents.

Dose-area-product (DAP) modelling of Siemens Max-series X-ray digital radiography (DR) systems

PurposeTo develop a dose-area-product (DAP) model of Siemens Max-series x-ray digital radiography (DR) systems for pre-exposure DAP estimation. Methods and materialsSeries of commissioning exposures were taken with varying x-ray tube voltage (kVp), and milliampere-second (mAs) and imaging protocols (thorax PA, pelvis and knee) on a Fusion Max and Ysio Max unit respectively. Correlations of dose-area-product (DAP) values with kVp and mAs were analyzed, and a quasi-linear model were proposed as DAP(mAs, kVp) = a∙mAs∙kVp + b∙kVp, which was validated on commissioning data. Then, the DAP estimation models were verified with clinical data from four radiology centers, and relative errors between model estimates and measurements were analyzed. ResultsField size, mAs and kVp are found to be the key factors that influence DAP values, which exhibit significant linear-correlations both with kVp and mAs. The model parameters (a, b) on Fusion and Ysio units are not equal, which indicates slight difference in imaging chains. The validation results show that the proposed DAP estimation model can well depict the DAP dependence on kVp and mAs on both units. In preliminary clinical verification, relative errors between model estimates and measurements are significantly correlated to field-size deviations. ConclusionsWhile the model parameters are field-size dependent, the proposed model framework exhibits great viability on DAP estimation on both Fusion Max and Ysio Max units, and may contribute in pre-exposure imaging parameter fine-tuning on Max-series DR units.

Evaluation of the Use of a Molybdenum Filter for Dose Reduction in Pediatric Digital X-ray Imaging

Pediatric dosimetry requires extra attention as young children are three times more sensitive to radiation than the average population. Soft tissues of patients absorb low-energy photons without affecting useful diagnostic information. X-ray filters can decrease the exposure dose of radiation by removing low-energy photons from the X-ray beam. Several studies have dealt with the advantages of a conventional filter, copper (Cu), in pediatric digital X-ray radiography. Only a few studies, however, have examined the use of molybdenum (Mo) filters and their impact on the radiation dose and image quality in pediatric digital X-ray imaging. In this study, we investigated the impact of a Mo filter on the image quality and the entrance surface exposure (ESE) in pediatric X-ray imaging and assessed the potential of additional dose reduction compared to a conventional Cu filter. The performance of the Mo filter was investigated and compared with that of Cu filter. Two types of phantoms were used: a customized quantitative phantom (Phantom A) for quantitative comparison and a computational anthropomorphic extended cardiac-torso (XCAT) phantom for qualitative comparison. A clinical radiography system was modeled, and the clinical setting for pediatric chest X-ray imaging was considered. Geant4 simulations using Monte Carlo toolkits were performed to obtain the images for pediatric chest X-ray examinations. Quantitative and qualitative comparisons using the quantitative phantom (Phantom A) and the XCAT phantom, respectively, were performed for both filters. From the customized quantitative phantom study, the ESE for the Mo filter was compared with that for the Cu filter when contrast-to-noise ratio (CNR) was equal. In addition, to validate our Monte Carlo model, we compared simulated and experimentally acquired images. From the results, the ESE for the Cu filter was 22.62 μGy while the ESE for the Mo filter was 18.18 μGy for 5-mm soft tissue. The use of a Mo filter results in a reduction in the dose by 19.60%. From the XCAT phantom study, the image for the Mo filter was superior to that for Cu filter in terms of noise and recognition of blood vessels. The performance characteristics of the Mo filter were evaluated in terms of image quality and radiation dose by comparing those characteristics to the ones for a conventional Cu filter. Our results demonstrated that the use of the Mo filter can significantly reduce the radiation dose. Based on this result, Mo filters are recommended for use in pediatric digital X-ray imaging.

An improved quality assessment of fuel pin end plug welds using digital X-ray radiography

In fast breeder reactors, the quality of fuel pin end plug welds is very important because the presence of any weld defect can cause fission products to be released into the coolant circuit. Among the various defects that can form during welding, a root defect at the end plug weld joint is the most prominent type observed in fuel pins. A conventional X-ray film radiographic procedure for end plug welds of fuel pins inserted in a stainless steel (SS) shape correction block with a thickness of 7 mm will limit the minimum detectable wall thickness difference to 1.1% of the specimen thickness due to film gradient and film granularity factors. In the present work, with a standard X-ray digital radiographic data acquisition procedure and optimised radiographic exposure conditions (kV, mAs, etc), the normalised signal-to-noise ratio (SNRn) achieved is 140, which limits the detectable wall thickness difference to 2.8% of the specimen thickness. Hence, a modified digital X-ray radiographic inspection procedure is proposed to assess the quality of end plug welded fuel pins using a suitable X-ray detector calibration technique. The structural noise and pixel intensity variations between the flat-panel pixel elements are minimised using this modified procedure, which results in an order of magnitude increase in the SNRn of the radiographic images. Following implementation of this procedure with end plug welds, the X-ray images show that the achievable wall thickness difference is enhanced to 0.9% of the specimen thickness and microdefects are clearly observed in the welds.

All-Inorganic Lead-Free Heterometallic Cs4MnBi2Cl12 Perovskite Single Crystal with Highly Efficient Orange Emission

Summary A luminescent all-inorganic manganese-bismuth heterometallic Cs4MnBi2Cl12 perovskite single crystal has been synthesized with a [BiCl6]3−-[MnCl6]4−-[BiCl6]3− triple-layered two-dimensional structure. Benefit from the effective energy transfer from [BiCl6]3− octahedron donor to luminescent [MnCl6]4− acceptor, Cs4MnBi2Cl12 shows a photoluminescence quantum yield (PLQY) of up to 25.7% (~610 nm), 51-fold higher than the Bi unalloyed CsMnCl3·2H2O counterpart. Suggested by the theoretical calculations, Bi and Mn exhibit hybridization in conduction and valence band, which further results in a favorable low activation energy for exciton transfer (~23 meV). By virtue of all-inorganic chemical composition, Cs4MnBi2Cl12 exhibits impressive stability toward moisture, light, and heat. Furthermore, Cs4MnBi2Cl12 features strong soft X-ray attenuation and bright radiative luminescence under X-ray excitation, which pave a way for its application in medical flat-panel X-ray digital radiography. This work presents a new avenue toward fabrication of function-directed material with tailored photoelectric properties.

Non-destructive test of watermark materials quality for art pottery using x-ray digital radiography

In this study, the quality of watermark materials for art pottery were tested using x-ray digital radiography. The embedded watermarks in art pottery were chosen from 3 materials namely wood, and polylactic acid (PLA), and acrylic. Watermarked potteries quality testing were carried out during the making process, namely before and after being burned. Watermarked potteries were tested with 60 kV tube voltage regulation, 16 mA strong current, and 0.16 s exposure time. The radiographic image results obtained were then analyzed using ImageJ software. There are 3 stages of testing, namely visual analysis, image line profile analysis, and linear attenuation coefficients analysis. The results of visual analysis show that there were no crack in the watermarks so that planting the watermark did not damage the pottery. The graph of image line profile analysis results shows that the watermark made from wood was most clearly seen on the radiographic image. The attenuation coefficient value in the watermarked part does not change before and after the burning process while the attenuation coefficient value of the pottery had increased due to the shrinking process of the pottery. Wood has the largest attenuation coefficient value difference with pottery, so making it suitable as a watermark material for art pottery.

Radiation exposure factors optimization of X-ray digital radiography for watermarked art pottery inspection

Non-Destructive Testing (NDT) is a technique for detecting a defect in an object without causing damage. NDT technology can be utilized in the arts for inspection purposes. The NDT technique that can be used for the inspection of art pottery is digital X-ray radiography. It can inspect until the contents inside the art pottery without causing damage. To obtain a high quality of watermarked art pottery image using digital radiography, the radiation exposure factors should be optimized. In this work, optimization was done by varying the voltage, current, and exposure distance. Then, the radiography images were analysed using Contrast to Noise Ratio (CNR). From the analysis, it can be determined that the optimum exposure factors are 60 kV of voltage, 16 mA of current, and 100 cm of exposure distance.

Synchronization of a camera and x-ray tube in digital radiography system in UNNES medical physical laboratory

Much development of medical devices has been made in the field of radiology. An example is the development of analog radiology into digital radiology. The result of a digital radiographic x-ray is a digital radiograph that can be processed further with image processing techniques. After that it can be printed (printed image) or sent by a teleradiology method. To increase the digital image results, a delay was needed between the opening of the camera lens and the x-ray exposure. Then a delay circuit optimization is needed between the DSLR (digital single lens reflex) cameras, and x-ray exposure on Arduino Uno-based analog radiographs which are used as a unit delay and relay. In the unit delay, a push button triggered a millisecond, so that the Arduino IDE program was needed to set a delay. The relay functioned as a separator between the DC (Direct Current) on the camera and the AC (Alternating Current) on the x-ray tube. The results obtained were that the longer the x-ray exposure, the more intensity. Variation in delay time was regulated in the Arduino IDE program to get the best image quality with the least intensity of light to reduce radiation side effects in patients.

Gas Scintillation Imager With Capillary Plate

The glass capillary plate (CP) gas detector is a hole-type micropattern gas detector (MPGD) as well as a gas electron multiplier (GEM). An interesting feature of the hole-type MPGD is that since the electron multiplication takes place in each of the highly granulated holes, pixelized 2-D imaging with a high position resolution is possible. Using the CP, we have been developing a gas scintillation imager (GSI) for digital X-ray radiography, cosmic X-ray polarimetry, and neutron imaging. To realize the 2-D imaging capability, we exploit the visible and near-infrared (NIR) scintillation photons emitted from each hole upon gas excitation. This emission occurs simultaneously with electron multiplication. The readout of the scintillation photons has been carried out using an image-intensified charge-coupled device (CCD) or CMOS camera, or a cooled low-noise CCD/CMOS camera, coupled to an optical mirror or lens systems. In this article, we review the properties of the GSI as X-ray and neutron imagers and describe the outlook for future developments.

Inspeksi Material menggunakan Mikro-Radiografi Sinar-X Digital melalui Pengukuran Densitas

X-ray digital radiography is a non-destructive digital imaging technique that utilizes X-ray radiation that penetrates material objects. This technique can be used to analyze the internal structure and composition of objects properly. Research has been carried out on material inspection using X-ray digital micro-radiography that has been developed in the Physics Department, FMIPA UGM. Material samples inspected were 2B and HB pencils. All samples were irradiated by X-rays with a tube voltage of 30 kV and a filament current of 20 mA. Several images were taken for each sample, then averaged and calculated the grayscale value (intensity). Density was calculated based on variations in the intensity difference that passes through the pencil. The radiographic image showed that the internal structure of the pencil object, were wood and graphite can be distinguished. The measurement results were obtained for HB pencils, the value of the graphite density of HB pencils was (2,52 ± 0,02) g/cm 3 and graphite density of 2B pencils was (1,84 ± 0,02) g/cm 3 . The results of density different between HB graphite and 2B graphite indicate that X-ray radiography techniques can be an alternative for material inspection purposes and density measurement.

Mechanical and radiation shielding properties of flexible material based on natural rubber/ Bi2O3 composites

The purpose of this investigation have been developed lead-free and flexible radiation shielding materials. Composites of natural rubber (NR) were prepared by incorporating bismuth oxide (Bi2O3) with various loading levels. The variation mechanical properties of the composite with different loading levels have been studied. The gamma ray shielding properties were measured with 137Cs (662 keV) source by Compton scattering technique. The X-ray shielding characterization were measured with high frequency digital radiography X-ray machine Shimadzu model RAD Speed Pro. The results show that addition of Bi2O3 into natural rubber enhances the modulus at 100% elongation, hardness and specific gravity of the composites, whereas tensile strength and elongation at break reduces. For gamma ray shielding properties, the experimental values of mass attenuation coefficients (μm), effective atomic number(Zeff), effective electron densities (Ne) and lead equivalent of the NR composites were found to increase with the increasing of Bi2O3 concentrations, while these value were decrease with the increasing of photon energy from 223 keV to 662 keV. The half value layer (HVL) values of all samples were decreased with the increasing of Bi2O3 concentrations. The NR of 150 phr Bi2O3 composites found to be the lowest HVL values in comparison with commercial window, serpentine, ordinary concrete and hemimatite-serpentine. For X-ray shielding properties, the linear attenuation coefficient (μ) and lead equivalent (dPb) were increased with increased Bi2O3 add in NR and show the decreasing of X-ray energies range.

Wall Thickness Measurement of Pipes Using Digital Radiography and Three Wavelet Methods

Digital X-ray radiography is a well established method for non-destructive detection of corrosion and measurement of wall thickness of pipes. Due mainly to the unavoidable detection of scattered X-rays as well as the ever-present system electronic noise, the quality of the acquired radiographs is often low; the quality can however be enhanced by applying various image processing methods. In this research, Wavelet Transform (WT), Gabor Filters (GF) and Shearlet Transform (ST) have been utilized in a background removing algorithm to achieve the required radiographic image quality improvement. The algorithm first decomposes the image into different levels using the WT, GF or the ST method, and the automatic thresholding level, which is based on Rayleigh distribution, is then applied. The output images (with the background removed) were then reconstructed by subtracting the modified component from the original radiograph. The results of the study showed that the reconstructed images yield significantly greater contrast than the original radiograph, the wall thickness measurements have higher precision and defect detection has greater specificity for defect in all regions. Also, the outcomes show that the algorithm has high analytical efficiency and is capable of accurately measuring pipe wall thicknesses and corrosion regions.

Performance analysis of digital X-ray radiography system in radiometallurgy installations for pebble bed fuel imaging

Research and studies on pebble bed fuel to support the realization of RDNK based on HTGR have been carried out by BATAN. Indicators of reliability of nuclear fuel are able to fulfill the criteria for irradiation testing and qualify in post irradiation tests. At present, Radiometallurgy Installation as a post irradiation examination location has completed installation of X-ray radiography equipment for non-destructive testing. Performance analysis includes the function of tools and the completeness of test support facilities. Digital X-ray radiography has a maximum voltage capability of 320 kV. X-rays are directed vertically towards the sample and sensor film. X-rays captured by film sensors can be seen directly in real time on a computer. To put the pebble bed fuel is provided a special holder. The X-ray radiography system trials were carried out on a pebble bed fuel model. The purpose of the trial to find out the performance of X-ray radiography systems in capturing the image of the pebble bed fuel model. The fuel model is made of ceramic which simulates graphite and lead material that simulates TRISO. The results obtained indicate that the X-ray digital radiography system is able to capture the image of the pebble bed fuel model with a good image.

Digital Imaging Detection and Image Analysis of Internal Structural Defects in GIS

The existence of internal structural defects in gas insulated combinations (GIS) seriously affects the normal operation of equipment, and it needs an efficient and non-destructive detection method. This study is focused on the feasibility of X-ray digital imaging detection in GIS equipment monitoring. First, the digital imaging detection process is briefly introduced. Then, in order to obtain high-quality digital images, a correlation coefficient is introduced to improve the nonlocal mean filtering denoising algorithm. In terms of image enhancement, a histogram equalization method is introduced, and then an improved contrast-limited adaptive histogram equalization (CLAHE) method is proposed for image denoising. The detection system and image processing method of this study are used to detect two GIS equipment units of the Chongqing Electric Power Company (China). It is found that this method clearly and accurately detects the equipment defects with high reliability. This study provides some theoretical basis for further promotion of the X-ray digital radiography in GIS equipment defect detection.

Methodology for the non-destructive characterization of jadeite-jade for archaeological studies.

The present paper proposes a methodology that complies with the requirements of identifying and characterizing jadeite (and its associated minerals) for archaeological studies, avoiding the acquisition of samples and ensuring the integrity of the object. The methodology exploits a carefully selected array of techniques (optical microscopy, UV fluorescence photography, X-Ray digital radiography, infrared and Raman spectroscopies, X-Ray fluorescence and particle induced X-ray emission spectroscopies) that, despite not definitively replacing laboratory procedures, provides a first mineral and elemental evaluation of jadeite archaeological objects. The proposed methodology was applied in the characterization of twelve different jade tones, allowing the identification of major - jadeite, albite and omphacite - and minor - pumpellyite, actinolite, analcime, rutile, grossular and titanite - mineral phases. To display its advantages and limitations, this methodology was also compared with a characterization employing specific gravity measurements and with an invasive methodology based on petrography and scanning electron microscopy with energy dispersive spectroscopy.

Estimates of Patient Radiation Doses in Digital Radiography Using DICOM Information at a Large Teaching Hospital in Oman.

In this study, we sought to estimate the patient radiation doses in the digital radiography X-ray examinations conducted in a large hospital. The patient exposure factors and kerma-area product (PKA) were retrospectively recorded via the Digital Imaging and Communications in Medicine (DICOM) header for 547 patients. The entrance surface air kerma (ESAK) was estimated from the measurements of the X-ray tube output and recorded exposure factors, as well as from the console that displayed PKA as an alternative method. Effective doses were estimated from ESAK and PKA values using the appropriate conversion coefficient. In the chest PA, chest LAT, cervical spine AP, cervical spine LAT, abdomen AP, pelvis AP, lumbar spine AP, and lumbar spine LAT, the median ESAK (mGy) was found to be 0.13, 0.27, 0.35, 0.52, 0.70, 1.06, 2.33, and 4.18mGy, respectively. Median PKA values were 0.10, 0.26, 0.14, 0.17, 0.77, 0.68, 0.81, and 1.11Gycm2, respectively. The estimated effective dose from ESAK and PKA values yielded comparable results. The comparison revealed that the ESAK and PKA values fell far below the reported in the literature. The results showed that the information of the DICOM deader is valuable for dosimetry and optimization.