Digital Detector Research Articles

Numerical analysis for jet flow field on cleaning the outer wall of the double-layer injection needle

To avoid cross-contamination between different samples, improve the cleaning effect of the outer wall of the inner needle of the digital PCR detector, and reduce the cost of cleaning solution, the cleaning jet was simulated by FLUENT software using VOF gas-liquid two-phase flow model and PISO algorithm. In a certain range, the inlet velocity, cleaning solution viscosity, interfacial tension, and contact angle are changed to simulate the theoretical cleaning of the outer wall of the injection probe and the selection of various parameters under the best cleaning conditions is determined. The results show that the increase of inlet velocity has no significant effect on the increase of wall static pressure and the decrease of velocity increases; the increase of viscosity will greatly reduce the flow rate; higher interfacial tension requires higher inlet velocity to form a continuous jet; increasing the contact angle will not significantly reduce the static pressure and flow rate, and the residual sample is easier to clean. When the inlet velocity of 200mm /s is selected, the fluorine oil with a viscosity of 0.00124Paꞏs and interfacial tension of 16.2dyn/cm is used and the wall is coated with Teflon, the cleaning effect, and economy are excellent.

Cone-Beam CT With Enhanced Needle Guidance and Augmented Fluoroscopy Overlay: Applications in Interventional Radiology.

Digital flat-panel detector cone-beam CT (CBCT), introduced in the early 2000s, was historically used in interventional radiology primarily for liver-directed therapies. However, contemporary advanced imaging applications, including enhanced needle guidance and augmented fluoroscopy overlay, have evolved substantially over the prior decade and now work synergistically with CBCT guidance to overcome limitations encountered with other imaging modalities. CBCT with advanced imaging applications has become increasingly used to facilitate a broad range of minimally invasive procedures, particularly relating to pain and musculoskeletal interventions. Potential advantages of CBCT with advanced imaging applications include greater accuracy for complex needle paths, improved targeting in the presence of metal artifact, enhanced visualization during injection of contrast medium or cement, increased ease when space in the gantry is limited, and reduced radiation doses versus conventional CT guidance. Nonetheless, CBCT guidance remains underutilized, partly relating to lack of familiarity with the technique. This article describes the practical implementation of CBCT with enhanced needle guidance and augmented fluoroscopy overlay and depicts the technique's application for an array of interventional radiology procedures, including epidural steroid injections, celiac plexus block and neurolysis, pudendal block, spine ablation, percutaneous osseous ablation fixation and osteoplasty, biliary recanalization, and transcaval type II endoleak repair.

A highly sensitive broadband superconducting thermoelectric single-photon detector

We propose a passive single-photon detector based on the bipolar thermoelectric effect occurring in tunnel junctions between two different superconductors thanks to spontaneous electron–hole symmetry breaking. Our superconducting thermoelectric detector (STED) converts a finite temperature difference caused by the absorption of a single photon into an open circuit thermovoltage. Designed with feasible parameters, our STED is able to reveal single photons of frequency ranging from ∼15 GHz to ∼150 PHz depending on the chosen design and materials. In particular, this detector is expected to show values of the signal-to-noise ratio SNR ∼ 15 at ν = 50 GHz when operated at a temperature of 10 mK. Interestingly, this device can be viewed as a digital single-photon detector, since it generates an almost constant voltage VS for the full operation energies. Our STED can reveal single photons in a frequency range wider than four decades with the possibility to discern the energy of the incident photon by measuring the time persistence of the generated thermovoltage. Its broadband operation suggests that our STED could find practical applications in several fields of quantum science and technology, such as quantum computing, telecommunications, optoelectronics, THz spectroscopy, and astro-particle physics.

An inclined detector geometry for improved X-ray total scattering measurements.

X-ray total scattering measurements are implemented using a digital flat-panel area detector in an inclined geometry and compared with the traditional geometry. The traditional geometry is defined here by the incident X-ray beam impinging on and normal to the center-most pixel of a detector. The inclined geometry is defined here by a detector at a pitch angle α, set to 15° in this case, bisected by the vertical scattering plane. The detector is positioned such that the incident X-ray beam strikes the pixels along the bottom edge and 90° scattered X-rays impinge on the pixels along the top edge. The geometric attributes of the inclined geometry translate into multiple benefits, such as an extension of the measurable scattering range to 90°, a 47% increase in the accessible magnitudes of the reciprocal-space vector Q and a leveling of the dynamic range in the measured total scattering pattern. As a result, a sixfold improvement in signal-to-noise ratios is observed at higher scattering angles, enabling up to a 36-fold reduction in acquisition time. Additionally, the extent of applied modification functions is reduced, decreasing the magnitude of termination ripples and improving the real-space resolution of the pair distribution function G(r). Taken all together, these factors indicate that the inclined geometry produces higher quality data than the traditional geometry, usable for simultaneous Rietveld refinement and total scattering studies.

Zinc aluminate (ZnAl2O4) applied in the development of a propane gas sensor and in the design of a digital gas detector

Zinc aluminate (ZnAl2O4) applied in the development of a propane gas sensor and in the design of a digital gas detector

Literature Review on X-Ray Image Enhancement

In common, a raw X-ray image holds bad quality of the image if obtained directly coming out of a digital flat detector. It isn't satisfactory for treatment planning as well as diagnosis. For this image, enhancement is required. There are distinct ways through which image enhancement takes place. It is one of the preprocessing techniques helpful for moving further into treatment planning. Common methodologies like N-CLAHE which works with local enhancement and global enhancement can make an image look more extensive and more realistic. This technique consists of two main steps. Firstly, intensity correction of the raw image is encountered by the log-normalization function which adjusts the intensity contrast of the image dynamically. Secondly, the Contrast Limited Adaptive Histogram Equalization (CLAHE) method is used for enhancing small details,texture and local contrast of the images. For purpose of the survey, light is thrown on some of the wellknown developed models, the strategies used, and the shortcomings which were encountered in the development. This review will help researchers to further make advancements in this field

An Overview of Factors Affecting Exposure Level in Digital Detector Systems and their Relevance in Constructing Exposure Tables in Equine Digital Radiography.

The aim of this review is to describe the steps of constructing exposure tables for use of digital detector systems (DRx) in equine practice. Introductory, selected underlying technical aspects of digital radiography are illustrated. Unlike screen-film radiography (SFR), DRx have a uniform signal response of the detector over a large dose range. This enables generation of diagnostic images from exposures that were previously nondiagnostic on SFR, thus reducing retakes. However, with decreasing detector entrance dose, image noise increasingly hampers the image quality. Conversely, unlike the blackening observed on SFR, overexposures can go visibly undetected by the observer. In DRx the numeric exposure indicator value is the only dose-control tool. In digital radiography the challenge is to reduce the dose and reduce the radiation risk to staff whilst maintaining diagnostic image quality. We provide a stepwise method of developing exposure tables as tools for controlling exposure levels. The identified kVp - mAs combinations in the table are derived from the predefined exposure indicator values of the detector system. Further recommendations are given as to how the exposure indicator can be integrated into routine workflow for rechecking the reliability of the formerly identified settings and how these tables might serve a basis for further reduction of the exposure level. Detector quantum efficiency (DQE) is an important parameter of assessing performance of an imaging system. Detectors with higher DQE can generate diagnostic images with a lower dose, thus having a greater potential for dose reduction than detectors with low DQE.

IOT enabled Intelligent featured imaging Bone Fractured Detection System

In the present era, there are lots of advancements and initiatives that have been undertaken through image processing techniques and IoT (Internet of Things). Image processing has proven its valuable insights in various applications such as GIS, biomedical, security, satellite imaging, medicine, and personal image analysis. In the context of fracture detection, image improvements, feature segmentation, and feature extraction techniques are commonly implemented including in the IoT Environment. The lower long bone, hand bone, and elbow bones are the particular interest due to their high incidence of fractures. X-ray diagnosis is a common method of detecting bone fractures due to its rapid and widespread availability. X-ray imaging involves a small amount of ionizing radiation in each part of the body, which is then captured on a particular film or digital detector. X-ray images, though they may have limitations compared to other imaging modalities, provide sufficient quality for fracture detection. There are three points of motivation for this research i.e. First- ease of use of software for patients and reduce the time for doctors and patients by screening out straight forward, Second- to decrease human mistakes that can also occur from manually inspecting a massive dataset of X-ray images to become aware of fractured sections of bones in hospitals, third- use of IoT infrastructure to collecting images of X-Rays and performing processing on received data by which we can send some accurate information back to the patients. The research aims to develop an automated environment i.e IoT emulation Framework consisting of image pre-processing such as attainment of images, pre-post-processing, segment methods, feature extraction, fracture detection, and visualization. Feature Extraction algorithm includes, CLAHE object with the preferred clip limit 2.0, CLAHE to the grayscale image, Gaussian blur to overcome more noise, Canny side detection, Hough Transform for line detection, and the gradient magnitude to acquire binary edges varied out through IoT. The framework utilizes the Canny edge detection methodology and Sobel operator for image segmentation. In this heat maps of images are also observed, which provide accurate information from bone images through IoT. The proposed system illustrates extreme accuracy and effectiveness, as proved by the results acquired from numerous experiments. The automated labeling and detection of bone fractures through photo processing by way of IoT offer great potential for fast and correct diagnosis, contributing to successful treatment outcomes.

Clinical Applications of Quantitative Perfusion Imaging with a C-Arm Flat-Panel Detector-A Systematic Review.

C-arm systems with digital flat-panel detectors are used in interventional radiology and hybrid operating rooms for visualizing and performing interventions on three-dimensional structures. Advances in C-arm technology have enabled intraoperative quantitative perfusion imaging with these scanners. This systematic review provides an overview of flat-panel detector C-arm techniques for quantifying perfusion, their clinical applications, and their validation. A systematic search was performed for articles published between January 2000 and October 2022 in which a flat-panel detector C-arm technique for quantifying perfusion was compared with a reference technique. Nine articles were retrieved describing two techniques: two-dimensional perfusion angiography (n = 5) and dual-phase cone beam computed tomography perfusion (n = 4). A quality assessment revealed no concerns about the applicability of the studies. The risk of bias was relatively high for the index and reference tests. Both techniques demonstrated potential for clinical application; however, weak-to-moderate correlations were reported between them and the reference techniques. In conclusion, both techniques could add new possibilities to treatment planning and follow-up; however, the available literature is relatively scarce and heterogeneous. Larger-scale randomized prospective studies focusing on clinical outcomes and standardization are required for the full understanding and clinical implementation of these techniques.

A digitally assisted IVD calibration bridge using a programmable digital detector

This paper presents a development of a digitally assisted coaxial bridge suitable for Inductive Voltage Divider's (IVD) calibration. The bridge uses a programmable digital detector (PDD) based on difference voltage measurement. The PDD used in the presented bridge senses the difference voltage and computes the ratio corrections of the test IVD with unbalanced bridge equations. The measurement results of the digitally assisted IVD calibration bridge are compared with the manual bridge, which is based on null balancing. The uncertainties achieved with the digitally assisted IVD calibration bridge are 0.55 μV/V and 0.56 μV/V for in-phase and quadrature corrections. However, uncertainties achieved in a manual bridge are 0.63 μV/V and 1.50 μV/V for in-phase and quadrature corrections respectively. The digitally assisted IVD calibration bridge is better than the manual bridge. It is simple, precise, fast, and user-friendly, hence it can be used for day-to-day calibration requirements.

Head‐to‐Head comparison between Philips Gemini TF64 and Siemens Biograph Vision 600 for brain amyloid Centiloid quantitation

AbstractBackgroundThe Centiloid (CL) scale calibrates the beta‐amyloid (Aβ) deposition from different PET tracers to a standardised 0‐100 CL unit scale. As imaging sites update their PET cameras, most are switching to digital detector systems with superior resolution and sensitivity that may affect quantitation. This has significant implications for dementia clinical trials. In this study, we examine the impact on CL quantification between Philips Gemini TF64 and Siemens Biograph Vision 600.MethodSeven subjects (76.4±2.2 yo) were imaged with 18F‐NAV4694 on both Gemini TF64 and Biograph Vision consecutively with an average scan interval of 25.1±11.2 weeks. The injected doses were 200MBq and 100MBq, respectively. On the Gemini TF64, the PET images were reconstructed by LOR‐RAMLA algorithm with smoothing parameter setup as ‘SHARP’. On Biograph Vision, the PET images were reconstructed by OSEM‐3D (8 iterations and 5 subsets, TOF enabled) with 3mm post Gaussian smoothing. A T1 MRI image was acquired for each subject. As per the standard Centiloid method the whole cerebellum was used as the reference in SUVR images, and all images were processed using CapAIBL to calculate the CL using both MR‐based and MR‐Less spatial normalisation.ResultFigure 1 shows the CL images of a subject scanned on Gemini TF64 and Biograph Vision within sixteen weeks. The Biograph Vision images have higher contrast and higher spatial resolution despite using half of the dose. Figure 2 shows the linear regression plot of the scanner comparison. Biograph Vision CL are progressively higher than those obtained from the Gemini TF64 as the CL value rises (Table 1). There were no significant differences between the MR‐based and MR‐less results.ConclusionBiograph Vision yields higher SUVR and therefore CL values compared to Gemini TF64 in a head‐to‐head comparison. These results show that the selection of PET camera has a significant impact on CL quantification, which needs to be considered when merging cohorts from different studies or changing cameras during longitudinal studies or trials. These initial results indicate that the CL difference could be corrected by a linear transform.

Carbon dioxide removal from biogas through sorption processes using natural and activated zeolite adsorbents

ABSTRACT Natural zeolite is among the low-cost materials that can be used to remove contaminants in biogas. The cleaning of biogas increases its energy density and reduces possible negative effects. The current study aimed to upgrade biogas using natural zeolites. The activation of natural zeolite was done using sodium hydroxide. The adsorbent samples were characterised using an XRF machine, while the biogas samples were analysed using Shimadzu gas chromatography and a portable digital gas detector. The effect of zeolite-to-water ratio on the carbonation process was investigated. In addition, the effects of biogas flow rate, adsorbent dose and contact time on the dry adsorption process were studied. The maximum CO2 uptake of zeolite was 4.8 and 0.2 mmol/g by dry adsorption and wet carbonation process, respectively. The results indicate that surface adsorption favoured by a low Si2O3/Al2O3 ratio was more prominent than carbonation that requires high basic oxides. The results showed that an increase in the dose of activated clay from 2.5 to 35 g increased the removal efficiency of CO2 from 11.2% to 79.8%, while the CO2 uptake decreased from 4.8 to 2.5 mmol/g. Furthermore, the experimental data fitted best to pseudo-first-order kinetics and the Bohart-Adams model for the breakthrough curve.

Hollow-Channel Paper Analytical Devices Supported Biofuel Cell-Based Self-Powered Molecularly Imprinted Polymer Sensor for Pesticide Detection.

Herein, a paper-based glucose/air biofuel cell (BFC) was constructed and implemented for self-powered pesticide detection. Our developed paper-based chip relies on a hollow-channel to transport fluids rather than capillarity, which reduces analysis times as well as physical absorption. The gold nanoparticles (Au NPs) and carbon nanotubes (CNTs) were adapted to modify the paper fibers to fabricate the flexible conductive paper anode/cathode electrode (Au-PAE/CNT-PCE). Molecularly imprinted polymers (MIPs) using 2,4-dichlorophenoxyacetic acid (2,4-D) as a template were synthesized on Au-PAE for signal control. In the cathode, bilirubin oxidase (BOD) was used for the oxygen reduction reaction. Based on a competitive reaction between 2,4-D and glucose-oxidase-labeled 2,4-D (GOx-2,4-D), the amount of GOx immobilized on the bioanode can be simply tailored, thus a signal-off self-powered sensing platform was achieved for 2,4-D determination. Meanwhile, the coupling of the paper supercapacitor (PS) with the paper-based chip provides a simple route for signal amplification. Combined with a portable digital multi-meter detector, the amplified signal can be sensitively readout. Through rational design of the paper analytical device, the combination of BFC and PS provides a new prototype for constructing a low-cost, simple, portable, and sensitive self-powered biosensor lab-on-paper, which could be easily expanded in the field of clinical analysis and drug delivery.

Knowledge, awareness, and practice survey on conventional radiographic methods and processing among dental students.

X-rays are electromagnetic waves produced by an X-ray machine and are used to observe the internal structures of patients. The X-rays pass through the body before being detected by the detector file or a digital detector behind the patient. To analyze the knowledge, awareness, and practice on conventional radiographic method and processing among the dental students. A well-framed questionnaire consisting of 10 questions were prepared and distributed among 100 dental professionals and students through the online Google forms link. The data were collected, tabulated in Excel sheets, and analyzed using the SPSS software. The Chi-square test was used to assess the P value. Sixty-five percentage of the participants are aware of conventional radiographic methods and 35% are not aware. The Chi-square test was done giving a P = 0.001 (<0.05), which is statistically significant. The dental students as compared to the other specialties have adequate and efficient knowledge and are aware of the conventional radiographic methods and its processing.

Radon levels and indoor air quality after application of thermal retrofit measures-a case study.

This study was conducted to evaluate the influence of thermal retrofit on radon levels in workrooms, and to determine whether the radon concentration in the building changes after the application of retrofit measures. In the first survey, digital Airthings Corentium Home radon detector was used for 1-month radon measurements during the heating season 2018/19. The daily averaged radon concentrations varied from 37 to 573Bq/m3 for 10 selected workrooms, while hourly averaged radon measurements showed extreme variations from 6 to 1603Bq/m3 due to radon fluctuations. In second survey, passive radon technique based on charcoal canister test kit was conducted in all basement workrooms in spring 2021. The averaged radon concentrations grouped according to flooring type in workrooms were 327Bq/m3 for parquet, 227Bq/m3 for ceramic tiles, 146Bq/m3 for vinyl flooring and 71Bq/m3 for laminate. Besides thermal insulation and airtight windows, noticeable differences in indoor radon concentration within the renovated building are primarily caused by different types of flooring. It includes various types of insulation from the ground/concrete slab: laminate, parquet (wood blocks), vinyl flooring, and ceramic tiles. Detailed analysis point out that laminate is more efficient way for radon protection than other types of flooring. An efficient ventilation system should be installed to avoid increasing occupational radon exposure and to provide healthy and comfortable indoor environment.

Radiation control of blanks manufactured using additive technology by digital radiography

Additive technologies, namely selective laser melting (SLM), are often used in manufacturing products of critical duty. At the same time, the SLM process may be accompanied by the appearance of specific defects in the product. We present the results of radiation monitoring of aviation blanks manufactures using addi­tive technology by digital radiography. A digital detector system was used as an X-ray converter. It is shown that the methods of film radiography traditionally used for control in the case of aircraft objects are not always effective. The method of digital radiography, on the contrary, is the most adequate. Comparison of the results of digital radiography with data of traditional radiography revealed that the time spent on radiation monitoring when using an automated manipulator is significantly reduced, while the monitor­ing performance increases dramatically. The results obtained can be used to improve the methods of radia­tion monitoring of aircraft objects manufactured using additive technologies.

Low-Velocity Impact, Free-Fall Drop Test of Prototype, and Failure Analysis of Hybrid Palm / Kenaf Reinforced MWCNT Phenolic Composites

ABSTRACT The research’s aim is to investigate the energy absorption, free-fall drop analysis, and failure analysis of Palm (P)/kenaf (K) fiber-reinforced MWCNT-phenolic composites. 3P:7K reinforced MWCNT–phenolic composites were made using manual mixing and hot pressing at 150°C with a pressure of 10 tonnes. Energy absorption was investigated using a drop weight impact tester. Free-fall drop test was performed to analyze the performance of the aircraft tray table prototype. Non-destructive testing was carried out to investigate the damage mechanism. The results demonstrate that as the impact energy increased from 1.50 J to 3.0 J, the crack length increased. There is a difference of 3% to 15% in the crack sizing between dye penetration and Digital Detector Array (DDA), indicating that DDA is more accurate. In the free-fall drop test, small cracks were detected in the dye penetration method on the prototype. The DDA approach, however, did not reveal any defects. The agglomerations were observed through DDA and Computed tomography. In this study, the hybrid CR/kenaf reinforced MWCNT modified phenolic composites exhibit superior performance that can act as an efficient and eco-friendly material for aircraft tray table application by preserving natural resources.

Dose Optimization and Image Quality in Digital Radiography: A Review Article

Imaging techniques have been upgraded due to the invention of digital radiography. This advancement has made a massive change in the development of diagnostic procedures. This technique has displaced conventional radiography with digital methods of radiography. This radiography technique was accepted in all kinds of radiography, excluding mammography. There are many assets of using a digital process for imaging, like good quality of image with less dose. It gave accurate diagnosis for assured quality of image with high resolution and to avoid overdose proper guidelines are needed. The technician should be well trained and have adequate knowledge of the appropriate use of digital radiography. The flat detector system depicts a more efficient way to form an image of high quality with a low dose; the quality of the image increases due to the storage phosphor. Many institutions have accepted this digital radiography as it has proven beneficial for diagnostic procedures. Digital radiography has a flat panel detector that results in a high-resolution image. It has been noticed that screen-film radiography has been superseded by Digital radiography. Nowadays, manufacturers have made many improvements derived from the detector and different technology to Digital radiography equipment. Due to digital imaging techniques, x-rays are allowed to store digitally that can use anytime by adjusting contrast according to the interest of vision. This technology has given assurity of not losing any radiograph and allows dispensing throughout hospitals digital by online technology derived from the web. There are so many assets of using digital radiography as it increases patient count. The vigorous high scale of the digital detector with as low as possible radiation dose for the proper usage of this technology, radiologists and radiographers should have adequate knowledge of various technical postulates &amp; image calibre. They should know how to tackle the problem of overexposure or radiation dose.

A Fast Digital Phase Frequency Detector with Preset Word Frequency Searching in ADPLL for a UHF RFID Reader

An All-Digital Phase-Locked Loop (ADPLL) is an architecture that is widely employed in the communication system due to the advancement of the Complementary Metal-Oxide-Semiconductor (CMOS) technology process. A 2.4GHz Radio Frequency Identification (RFID) system needs a frequency synthesizer in the local oscillator architecture of the transceiver to generate a stable frequency tuning range Therefore, in this paper, a Digital Phase-Frequency Detector (DPFD) is designed to achieve the phase and frequency acquisition in the ADPLL system. The proposed DPFD is divided into two main parts, the first is the Phase Detector (PD) and the second is the Frequency Detector (FD). The PD has managed to detect the presence of the phase difference by recognizing two different input signals. The FD, on the other hand, is capable to detect the higher frequency by identifying the output signals from the PD in digital formation. In addition, a control unit module is developed to control and adjust the Preset Word (PW) for the system by using a binary search scheme. Comparison results show that the final value of the PW from the simulation is the same as from the manual calculation (theoretical values). The digital PFD and the PW control modules are designed and simulated by using Verilog HDL code. These two designed modules will be integrated into the targeted ADPLL to achieve fast locking performance and ultra-low power for Ultra-High Frequency (UHF) RFID applications.

Flexible X-ray imaging detectors using scintillating fibers

We present early design and simulation work on a novel X-ray imaging detector. The intent of the FleX-RAY project is to create a digital X-ray detector that is capable of producing high-resolution images, is flexible enough to produce an image on a curved surface, and is capable of self-reporting its final shape. The X-rays will be detected on a sheet of scintillating optical fibers, which will guide the scintillation light to single-photon avalanche photodiodes. This setup allows the electronics and hardware to be moved out of the path of the X-ray beam, limiting the need for additional shielding. Self-shape-reporting will be achieved using a flexible ultra-thin glass substrate with optical waveguides and Bragg gratings, processed by femtosecond laser point-by-point writing. The functionalized glass substrate allows precise measurement of strains, which can be used to calculate the shape.