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Industrial process tomography possesses unique advantages in biphasic medium measurement and has received broad attention in the past decades. Aiming at the widely existing low-contrast biphasic medium, this article proposes a nonlinear ultrasonic transmissive tomography (UTT) approach using continuous-wave excitation. Considering the refraction effect at the biphasic interface, the reconstruction method with nonlinear forward problem and the prototype-based resolution enhancement algorithm is proposed with higher accuracy, resolution, and speed. The UTT system is improved with a high-voltage excitation module and fan-beam transducer array to evaluate the proposed method, where the performance is qualitatively and quantitatively compared with the state-of-the-art reconstruction algorithms and measurement techniques from different perspectives. The results show that the reconstruction performance is significantly improved where the size, shape, and position of the dispersed medium can be accurately discriminated. Accordingly, the ultrasonic tomography with continuous-wave excitation is proved to be feasible and efficient in the visualized measurement of low-contrast biphasic medium.

Electrical Capacitance Tomography (ECT) is a well-established industrial process tomography technique. Image reconstruction for the ECT is a nonlinear problem, and the inverse problem is usually ill-posed and ill-conditioned. Hence, the solutions for the ECT are not unique and highly sensitive to the measurement noise. In this paper, a novel tuned fuzzy algorithm is proposed for reconstructing accurate images to monitor the distribution of the multi-phase flow in the industrial process. The proposed algorithm utilizes a Tuned Fuzzy Inference System (TFIS) to overcome the nonlinear characteristics of the ECT system. The optimal parameters of the fuzzy membership functions are obtained using the Particle Swarm Optimization (PSO) technique. In the past few decades, the naturally inspired intelligent swarm algorithms got more attention due to their wide spectrum of research for real-world complex problems optimization. The proposed PSO-tuned fuzzy algorithm is fast since it does not require solving the forward problem to update the sensitivity matrix. Comparing the results with traditional reconstruction algorithms, the proposed algorithm performs better in visual effects and imaging quality, since the image edges and details are better preserved.

Today, in-situ analyzing and monitoring are imperative for ensuring successful and healthy industrial processes in confined environments. With the rapid development of digitization, augmented reality (AR) has been utilized for letting people immersively interact with the necessary information. However, there are still knowledge gaps between AR technique and domain users pertaining to effective analysis of complex data. Hence, new solutions empowering domain users would benefit the whole industry. In this study, we report an initial prototype supporting complex data visualization and analysis in entire 3D surroundings within industrial process tomography (IPT). Microsoft HoloLens 2 is equipped for users to interact with the 3D information characterizing the workflow of the industrial process with high immersion. Our work distinctly improves the performance compared to existing solutions, pointing the way towards how AR should be deployed and developed more efficiently for aiding IPT systems.

Electrical capacitance tomography is an industrial process tomography technology, mainly used to measure and plot two-phase flow and multi-phase flow. The technology is based on the properties of various dielectric constants between the phases of the measured substance. This work focuses on the improvement of particle swarm optimization and intelligent algorithms, especially for the parameter control of particle swarm optimization and intelligent algorithms. The efficiency of group optimization algorithms and intelligent algorithms that solve optimization problems. This paper mainly aims at the image reconstruction process in electrical capacitance tomography system, and proposes an image reconstruction algorithm based on intelligent algorithm and particle swarm algorithm. Combined with the experimental environment of the self-made electrical capacitance tomography system, the actual imaging effect of the algorithm was compared and analyzed with the traditional imaging algorithm, and the verification of the algorithm improvement effect was theoretically completed. According to the finite element analysis method, the internal area of the sensor is subdivided on the entire network, and three flow modes are modeled, which provides conditions for the construction of the following experimental environment. Based on the theory, the principle of the classic Landweber imaging algorithm is discussed in detail. Using the experimental environment with built-in electrical capacitance tomography system, experiments were conducted to visualize the gas–liquid two-phase flow. The traditional Landweber algorithm and imaging algorithm proposed in this paper are used to reconstruct the image using the obtained volume data. Through comparative analysis of the resulting images, the results show that the imaging algorithm proposed in this paper improves the accuracy of flow pattern recognition and image accuracy, which proves the improvement. The feasibility of algorithm and particle swarm algorithm.

Process tomography techniques play an important role in visualizing and monitoring industrial processes, which help to produce high quality product without affecting the work flow in plants. The industrial process tomography techniques, i.e. , electrical tomography and computerized tomography, have been widely applied. Such tomographic tools can be used to investigate various types of multi-phase flows, in which the components may differentiate in density, conductivity, and permittivity. In a gas-liquid-solid flow, however, it is usually difficult for the existing tomographic tools to visualize the distributions of all three phases. In addition, it is necessary to assume some simplifications, i.e. , by viewing two disperse phases as one unified phase. The objective of this research is to provide a dual-modality imaging tool by combining electrical capacitance tomography (ECT) and electromagnetic tomography (EMT). First, an integrated dual-modality sensor was designed and implemented on the same cross-section of the process vessel. Subsequently, dual-modality tomographic measurements were collected by a custom-built multi-channel impedance measurement system. The performance of the dual-modality sensor was verified by numerical simulations and experimental tests, showing that it can produce reliable ECT and EMT measurements at a satisfying signal-to-noise ratio. The complementary tomographic images can be obtained from ECT and EMT, and the distributions of two disperse phases, i.e. , gas and solid phases, can be observed. The preliminary image fusion results were also given by combining the information from both the ECT and EMT images.

Electrical capacitance tomography (ECT) exhibits several attractive features that are important for industrial process tomography applications. These features include low cost, high speed, and nonintrusive nature. However, due to its soft-field character, a relatively low image resolution is an outstanding challenge for ECT. While many efforts have been made to tackle this challenge by improvements in image reconstruction algorithms, relatively less has been done to enhance the basic ECT hardware sensor configuration and data acquisition process. In this paper, a new measurement acquisition strategy is introduced to increase image resolution when using adaptive ECT (AECT). The proposed strategy is based on the manipulation of synthetic electrodes plates (“metaplates”) formed by a set of combined smaller physical electrodes (segments). The synthetic electrodes are sequentially activated with partial overlap of constituent segments to provide a fine-stepped axial and/or azimuthal electronic scan along the entire sensor. Consequently, an increased number of independent capacitance measurements are made available. Reconstruction results using the proposed measurement acquisition strategy (AECT) are shown to illustrate the enhanced resolution and stability in the imaging of objects compared to conventional ECT sensors.

Computed tomography technology uses an electromagnetic radiation source or particulate radiation source, to analyze / study different samples that can range from living organisms to the most diverse objects (rocks, phantoms, etc.). The use of the radioactive materials may cause harm to the operator if he is exposed to the source of radiation, so aiming at the safety of the operator, the objective of this work is to develop an Internet of Things automation system for the opening of the Industrial Process Tomography source port for industrial tomography applications. Thus, this system can drive the stepper motors through this platform can be opened at a safe distance to the operator, avoiding the operator to take radiation dose to perform this operation. For the IPT project, five source ports were made so that each was positioned diametrically opposite each array of detectors. In this project we used 192Ir sources that have activity of 18,500 MBq and that were produced in the reactor IEA-R1, from the neutron bombardment of the pellet containing stable isotope 191Ir. The main characteristics of 192Ir are: half-life of 74.2 days; radiation energy from 0.13 to 0.65 MeV. For the safety of the operator during the opening of the sources, an automated opening system with IoT that can be activated with software installed on the tomography or by a smartphone application by the MQTT protocol, which makes it possible to be monitored in real time at long distance showing the opening and closing status of each source port.

Industrial process tomography (IPT) based process control is an advisable approach in industrial heating processes for improving system efficiency and quality. When using it, appropriate dataflow pipelines and visualizations are key for domain users to implement precise data acquisition and analysis. In this article, we propose a complete data processing and visualizing workflow regarding a specific case—microwave tomography (MWT) controlled industrial microwave drying system. Furthermore, we present the up-to-date augmented reality (AR) technique to support the corresponding data visualization and on-site analysis. As a pioneering study of using AR to benefit IPT systems, the proposed AR module provides straightforward and comprehensible visualizations pertaining to the process data to the related users. Inside the dataflow of the case, a time reversal imaging algorithm, a post-imaging segmentation, and a volumetric visualization module are included. For the time reversal algorithm, we exhaustively introduce each step for MWT image reconstruction and then present the simulated results. For the post-imaging segmentation, an automatic tomographic segmentation algorithm is utilized to reveal the significant information contained in the reconstructed images. For volumetric visualization, the 3D generated information is displayed. Finally, the proposed AR system is integrated with the on-going process data, including reconstructed, segmented, and volumetric images, which are used for facilitating interactive on-site data analysis for domain users. The central part of the AR system is implemented by a mobile app that is currently supported on iOS/Android platforms.

This article describes the implementation of microwave tomography for industrial process applications. Microwave tomography for industrial process imaging has different requirements from that for medical imaging. In addition to spatial resolution, high temporal resolution or real-time imaging is also important for high-speed processes, flows, or rapid reactions. Depending on the specific application, both quantitative imaging and qualitative imaging may be needed. Qualitative imaging would be sufficient to display distributions, patterns, or shapes, which may be adequate for some applications. Quantitative imaging would, however, be more informative, giving images with quantitative dielectric contrast or permittivity values from which other physical parameters, such as density, moisture content, and phase fraction, may be derived. With the microwave tomography approach described, several example applications in industrial processes are demonstrated, and a number of experimental imaging results are presented.

In a typical catalytic trickle bed type of process reactor, capturing representations of steady-state flow features as well as situations like channelling or bypassing is a challenging task. Transmission-type industrial process tomography (PT) based on gamma radiation can be employed in many chemical and process industries as a tool for localizing the problem area for quick and economical troubleshooting. Industrial PT technology often makes use of either penetrating radiation like radioisotope based gamma rays, X-rays, microwaves or ultrasonic waves. We have developed a new gamma-ray transmission tomography system in collaboration with the Indian Oil Corporation Ltd. (IOCL R&D Unit, Faridabad, India). The system makes use of thirty two scintillator based gamma-ray detectors in addition to a host of other sub-systems. This paper evaluates the performance of the system considering systematic and automated data acquisition, capabilities of the reconstruction software as well as experimental verification using actual flow dynamics in the process column to map the steady state three phase liquid gas flow distribution across a plane in the presence of catalyst.

The paper discusses the capabilities of industrial computed tomography (CT) in the field of dimensional measurement of products with close tolerances. Computed tomography is a method that allows inspection and measurements of both reachable and unreachable characteristics which makes it very desirable and interesting for application in wide range of industries. In order to evaluate the quality of measurement results obtained by industrial CT, two objects with the same geometry, and made from different materials, were measured. Results obtained with CT were compared with the results obtained by coordinate measuring machine, which were considered to be reference values, and deviations between the results have been analysed. Measurements were repeated five times under repeatability conditions. Repeatability is expressed quantitatively in terms of the dispersion characteristics of the results. Statistical analysis showed that in majority of cases, there were no statistically significant differences between measurement results of equal characteristics obtained at different materials. Obtained deviations in the research could be explained by the fact that the measurements were performed at the industrial CT for general applications. Much better results can be achieved by using a metrology CT device.

The use of three-dimensional (3D) printing allows for creation of custom models for clinical care, education, and simulation. Medical imaging, given the significant role it plays in both clinical diagnostics and procedures, remains an important area for such education and simulation. Unfortunately, the materials appropriate for use in simulation involving radiographic or ultrasound imaging remains poorly understood. Therefore, our study was intended to explore the characteristics of readily available 3D printing materials when visualized by computed tomography (CT) and ultrasound.Seven 3D printing materials were examined in standard shapes (cube, cylinder, triangular prism) with a selection of printing methods ("open," "whole," and "solid" forms). For CT imaging, these objects were suspended in a gelatin matrix molded to match a standard human CT phantom. For ultrasound imaging, the objects were placed in acrylic forms filled with a gelatin matrix. All images were examined using OsiriX software.Computed tomography imaging revealed marked variation in materials' Hounsfield units as well as patterning and artifact. The Hounsfield unit variations revealed a number of materials suitable for simulation various human tissues. Ultrasound imaging showed echogenicity in all materials, with some variability in shadowing and posterior wall visualization.We were able to demonstrate the potential utility for 3D printing in the creation of CT and ultrasound simulation models. The similar appearance of materials via ultrasound supports their broad utility for select tissue types, whereas the more variable appearance via CT suggests greater potential for simulating differing tissues but requiring multiple printer technologies to do so.

The measurement of volume fractions of different components in multiphase flows is of great interest in many industrial applications. Ultrasound process tomography is especially well-suited for the differentiation of gaseous and liquid phases. This paper presents a measurement system, which was developed for real-time ultrasound process tomography, utilizing a ring of 32 ultrasound transducers on a measurement pipe. Simulations and measurements were conducted, and a reflection-mode reconstruction technique was used to obtain the system's point spread function and examine the performance on inhomogeneous configurations of water containing multiple gaseous objects. Furthermore, the possibility of increasing the measurement rate by reducing the number of excitations and its effects on the quality of the reconstructed images is investigated.

The needs and the feasibility of simultaneous computed tomography (CT) and magnetic resonance imaging (MRI) were recently reported. In this paper, a spiral magnetic resonance X-ray CT (MRX) imaging system is proposed for head and extremities imaging, which serves as a simple, cost-effective solution on the path to a full-scale CT-MRI fusion. While MRI and X-ray radiography were integrated before, we propose novel designs to acquire simultaneous CT and MR views for synchronized radiographic imaging or joint tomographic reconstruction. Our preliminary permanent magnet configurations achieve a magnetic field strength between 0.1 and 0.2 T while keeping weight low enough for portability. We have also shown that a field strength up to 0.35 T is achievable with permanent magnets that maintain a compact profile, though increased weight would hinder ease of transportation. Simulation results of a joint tomographic reconstruction scheme show the advantage of simultaneously acquired images. The proposed MRX system performs double helical scans in CT and MRI mechanisms, and has multiple niche applications, such as medical imaging on disaster sites, in battle fields, and for under-developed regions.

Industrial Process Tomography possesses unique advantages in biphasic medium measurement and has received broad attention in the past decades. Aiming at the widely existed low contrast biphasic medium, this paper proposed a nonlinear Ultrasonic Transmission Tomography (UTT). Approach using continuous wave excitation. Considering the refraction effect at the biphasic interface, the reconstruction method with nonlinear forward problem and the improved Simultaneous Algebraic Reconstruction Technique (SART) is proposed with high reconstruction accuracy and reconstruction speed. The performance of the reconstruction is quantitatively compared with the state-of-art reconstruction algorithms, where the proposed method can reconstruct inclusions with their number, size and position clearly identified. Quantitatively, the average Relative Error (RE) is 0.4835 using the proposed method, which is reduced by 49.34% and 40.57% compared with FBP and SART separately. Under parallel computation, the computing time of the proposed method reduced 16.56 times compared with the existing bent-ray tracing method. The proposed image reconstruction algorithm is proved to be an effective and improved approach to the liquid-liquid two-phase flow ultrasonic tomography.

Industrial process tomography (IPT) is a set of multi-dimensional sensor technologies and methods that aim to provide unparalleled internal information on industrial processes used in many sectors [...]

O uso da tomografia computadorizada despertou o interesse das indústrias pela possibilidade em utilizar as informações tomográficas de um produto, de processo ou de equipamento, para auxiliar no controle da qualidade de produtos e também para aperfeiçoar o processo produtivo. Porém, quando se trata de tomografia industrial, ao contrário da já amplamente utilizada tomografia médica, nem sempre as condições para a realização da aquisição tomográfica são favoráveis, pois os objetos industriais podem ter diferentes dimensões, composição química e densidades. O objetivo deste trabalho foi desenvolver um novo desenho para o sistema de tomografia computadorizada industrial, Industrial Process Tomography (tomógrafo), para análises de sistemas multifásicos. Nesta proposta, foram utilizados 70 conjuntos de cristais detectores de NaI(Tl) fotomultiplicadoras, ligados a 5 módulos com 12 detectores. A configuração desenvolvida permitiu a obtenção de um halo de 360° ao redor do objeto a ser tomografado, além da análise em tempo real do processo industrial. O sistema de porta-fontes, desenvolvido para este projeto, permite acomodar dois isótopos radioativos, que com a eletrônica do tipo multicanal, também desenvolvida durante este projeto, possibilitou realizar a seleção de várias faixas espectrais, ao mesmo tempo, em cada detector. O porta-fontes ainda conta com sistema de abertura e de fechamento à distância, para segurança do operador. O tomógrafo, desenvolvido para este trabalho, atendeu às expectativas. Seu desenho possibilita o transporte para as plantas de trabalho, pois este tomógrafo é modular, e apresentou também os picos característicos referentes aos espectros radioativos utilizados, além de apresentar um tempo de aquisição de espectros rápido, o que possibilita a realização de tomografias em tempo real. Computerized tomography has promoted the interest of industries for the possibility of using the tomographic data of a product, process, or equipment for quality control of a product, and improve the production process. However, unlike the already widely used medical tomography if compared to industrial tomography, the conditions to perform tomographic acquisition are not always favorable, once industrial objects may have different dimensions, chemical composition, and densities. The aim of this work was to develop a new design for the Industrial Process Tomography (IPT), for multiphase analysis. In this work, 70 sets of photomultiplier with NaI(Tl) detector crystals, connected to 5 modules with 14 detectors, were used. The developed configuration allowed to obtain a 360 ° halo around the object to be tomographed, and, also, real-time analysis of industrial processes. The source holder system developed can accommodate two radioactive isotopes, which with the multichannel electronics as well developed during this project, made it possible to select several spectral bands at the same time, in each detector. The source holder also has a remote opening and closing system for operator safety. The tomography developed for this work reached the expectations; its design turns it possible to transport it to the industrial plants because this tomography is modular, it also presented the characteristic peaks related to the radioactive sources spectra used, besides presenting a fast spectra acquisition time, which enables real-time CT scans.

As an irreplaceable part of industrial process, catalysts characteristics in the reaction process are getting more and more research. However, the traditional detection methods are off-line measurements, and the state of the catalysts cannot be known in real time, which does not do much effect on guiding the chemical reactions and production. Industrial Process Tomography (PT) is a method for online monitoring of multi-phase flow, in which Electromagnetic Tomography (EMT) has good imaging performances for particles with certain permeability or conductivity. Prior to EMT measurements, the electromagnetic properties of particles have to be acquired. In the previous research, a method for measuring the equivalent permeability of particle mixtures was proposed, in which the measurement system consisted of a four-tap solenoid coil sensor and a LCR meter. Based on our previous research, a portable measurement equipment has been designed to replace the LCR meter. This kind of instruments can work in different frequency conveniently and its SNR ranges from $\mathrm56.3~dB$ to $\mathrm78.5~dB$. Experimental results in frequencies $\mathrm31.25~kHz$ and $\mathrm500~Hz$ show that the relative errors of the developed system are below 8.14%.

A new imaging algorithm of permittivity for Electrical Capacitance Tomography (ECT) was proposed in this paper. Some aspects of sensitivity analysis and the application of adjoint variables were discussed. In the final section of this paper some advantages and disadvantages were shown.

We investigate the potential of using ultrasonic diffraction tomography technique for characterization of biological tissues. Unlike most of other studies where ultrasonic tomography operates at frequencies higher than 1 MHz, low-frequency tomography uses lower frequencies on the order of 0.3–0.5 MHz. Such a choice is due to low attenuation at these frequencies, resulting in higher precision of input data. In this paper we explore transmission and reflection schemes for both 2D (layer-by-layer) and 3D tomography. We treat inverse tomography problems as coefficient inverse problems for the wave equation. The time-domain algorithms employed for solving the inverse problem of low-frequency tomography focus on the use of GPU clusters. The results obtained show that a spatial resolution of about 2–3 mm can be achieved when operating at the wavelength of about 5 mm even using a stationary 3D scheme with a few fixed sources and no rotating elements. The study primarily focuses on determining the performance limits of ultrasonic tomography devices currently designed for breast cancer diagnosis.

This study describes the development of a multisource computed tomography (CT) system that proved to be a useful tool to study multiphase systems. In this CT system, two different radioisotope sources, 192 Ir (317 keV and 448 keV) and 137 Cs (662 keV), were placed in a single lead collimator and several tomography measurements carried out. The multisource CT system was capable of determining as well as differentiating the attenuation coefficients of materials with two phases (gas and liquid). It was also able to provide important information concerning the hydrodynamics occurring inside a multiphase column.

Ultrasonic tomography is a powerful tool for identifying defects within an object or structure. But practical application of ultrasonic tomography to solids is often limited by time consuming transducer coupling. Air-coupled ultrasonic measurements may eliminate the coupling problem and allow for more rapid data collection and tomographic image construction. This research aims to integrate recent developments in air-coupled ultrasonic measurements with current tomography reconstruction routines to improve testing capability. The goal is to identify low velocity inclusions (air-filled voids and notches) within solids using constructed velocity images. Finite element analysis is used to simulate the experiment in order to determine efficient data collection schemes. Comparable air-coupled ultrasonic signals are then collected through homogeneous and isotropic solid (PVC polymer) samples. Volumetric (void) and planar (notch) inclusions within the samples are identified in the constructed velocity tomograms for a variety of transducer configurations. Although there is some distortion of the inclusions, the experimentally obtained tomograms accurately indicate their size and location. Reconstruction error values, defined as misidentification of the inclusion size and position, were in the range of 1.5-1.7%. Part 2 of this paper set will describe the application of this imaging technique to concrete that contains inclusions.

The concept of creating a composite tissue-type-image (cTTI) along with an associated probability image is introduced for ultrasound and microwave tomography. The cTTI integrates information available within different quantitative property images, and the associated probability image provides an indication of the level of confidence regarding the reconstructed tissue types. It is shown that the cTTI concept can be applied to ultrasound tomography property images, microwave tomography property images, as well as to their combination. Thus, the concept is generalizable to the amalgamation of quantitative information derived from a wide variety of modalities with the goal of increasing the confidence in the reconstructed cTTI. Validation of the concept is performed on MRI-derived numerical breast phantoms containing up to five different tissue types.

Oil-water biphasic medium widely existed in mining and transportation process of petroleum industry, where visualized measurement processes vital importance in production increase, state monitoring and fault prognosis. Ultrasonic Tomography (UT) is a non-invasive and non-radioactive sensing modality in industrial Process Tomography, which is demonstrated as a competitive monitoring technique with great potential. However, facing the refraction effect of Ultrasound wave at oil-water interfaces, the accuracy of reconstruction algorithm is with large error and serious artifacts. To address the issue, a modified ray-tracing image reconstruction algorithm is proposed. The amplitude attenuation during ultrasound propagation in nonhomogeneous medium is quantitatively modeled to form absolute UT model. With ray tracing strategy applied and improved, the nonlinear refraction effect is characterized in the form of iterative update of sensitivity matrix, followed by which the sound speed mapping transfers reconstructed attenuation images to sound speed distribution for ray tracing computation. Numerical tests indicate that the proposed method significantly improves reconstruction accuracy through projection-based, regularization-based and algebraic-based inverse algorithms, which demonstrate its benefits in conducting oil-water biphasic medium imaging.

Electrical resistance tomography (ERT) and electrical capacitance tomography (ECT) are two established process tomography techniques that can be applied into various indsutries. ERT can monitor the electrical conductivity changes in the process whereas ECT can detect the electrical dielectric materials. Due to their high-speed and low cost features, they are particularly attractive to industrial applications which require real time conditional monitoring. For the past decades, 2D linear back projection (LBP) has been the standard technique for both commercialised ERT and ECT systems because of its simplicity and fast reconstruction speed. In this paper, ITS Plc has released a 'Reconstruction Tool-Suite' software that allows industrial users to utilise different reconstruction algorithms to further understand their processes. Different algorithms are integrated into this software package including the single step Tikhonov method and the iterative Landweber method. In the latest version of the software, the full-field 3D tomography reconstruction scheme is also included, which allows the users to perform 3D reconstruction for their processes. A series of experiments are conducted to validate the pros and cons of different methods.

Three-phase flow imaging is a very challenging problem in industrial process tomography. A particular interest here is three phase flow including both conductive and non-conductive phases. Currently there is no robust solution to this problem. Electrical capacitance tomography (ECT) has been applied to visualize the permittivity distribution by measuring inter-capacitance between electrodes around sensing area. Magnetic inductance tomography (MIT) is a technique to image the conductivity distribution through the inductance measurements over the coils around the sensing area. In this paper, the three-phase flow is classified into two scenarios: air background and water background. A dual-modality method of ECT and MIT is proposed to image both the conductive and dielectric components under test. As a result of this experiment, the dual-modality method is able to solve air-background three-phase flow imaging, but a problem has been raised in the water-background scenario. The static experiment results are promising for such contactless three phase flow imaging.

Tomography is a non-invasive, non-intrusive imaging technique allowing the visualization of phase dynamics in industrial and biological processes. This article reviews progress in Electrical Capacitance Volume Tomography (ECVT). ECVT is a direct 3D visualizing technique, unlike three-dimensional imaging, which is based on stacking 2D images to obtain an interpolated 3D image. ECVT has recently matured for real time, non-invasive 3-D monitoring of processes involving materials with strong contrast in dielectric permittivity. In this article, ECVT sensor design, optimization and performance of various sensors seen in literature are summarized. Qualitative Analysis of ECVT image reconstruction techniques has also been presented.

Electrical capacitance tomography (ECT) is a well-established industrial process tomography technique. The application of ECT is generally limited to imaging insulating objects with permittivity contrast. Although ECT imaging for grounded conductors are studied earlier, there is not a systematic study of imaging floating metals using ECT. To broaden the application of the ECT, imaging of suspended metallic samples is studied in this paper. Placing a metallic conductor between electrodes has an effect of shortening the spacing between the electrodes, thus the capacitances are increased. This increment in capacitances can be regarded as placing a dielectric sample with higher permittivity than the reference data. An ECT image of the floating metallic samples can be reconstructed using traditional sensitivity based image reconstruction, which is in the same way as imaging dielectric permittivity. In this paper, both metallic and dielectric samples are tested, and the results show the feasibility of ECT imaging for floating metals.

The main advantages of the use of computed x-ray tomography for nondestructive testing of the state of the internal structure of laminated polymer composite materials with the aim of improving the quality of manufacture of products from composites have been demonstrated.

Process tomography is a technique to realize flow imaging in a process vessel or pipeline by using the sensor system. This technique involves the use of tomographic imaging methods to manipulate data from sensors in order to collect sufficient information about the flow in the pipeline. The overall aim of this paper is to investigate the benefits of dual modality (optical and electrodynamic) tomography system for the measurement of tomographic images of solids flow. This research will investigate the distribution of conveying plastic beads in a conveying pipe by placing optical and electrodynamic sensors around the pipe without interrupting the flow inside the pipe.

This chapter focuses on the hardware of current and emerging X-ray computed tomography (CT) systems. First, the basic configuration of industrial cone-beam X-ray CT systems is recalled. Subsequently, individual hardware components, such as sources, detectors and kinematic systems, are described. The chapter continues with an overview of novel developments that expand the application domain of X-ray CT towards, for example, larger objects or fully integrated in-line systems. The chapter is concluded by a description of key safety elements for operation of X-ray CT systems.

We introduce an ultrasonic quantitative imaging method for long bones based on full-waveform inversion. The cost function is defined as the difference in the L 2-norm sense between observed data and synthetic results at a given iteration of the iterative inversion process. For simplicity, and in order to reduce the computational cost, we use a two-dimensional acoustic approximation. The inverse problem is solved iteratively based on a quasi-Newton technique called the Limited-memory Broyden-Fletcher-Goldfarb-Shanno method. We show how the technique can be made to work fine for benchmark models consisting of a single cylinder, and then five cylinders, the latter case including significant multiple diffraction effects. We then show pictures obtained for a tibia-fibula bone pair model. Convergence is fast, typically in 15 to 30 iterations in practice in each frequency band used. We discuss the so-called 'cycle skipping' effect that can occur in such full waveform inversion techniques and make them remain trapped in a local minimum of the cost function. We illustrate strategies that can be used in practice to avoid this. Future work should include viscoelastic materials rather than acoustic, and real data instead of synthetic data.

In electrical impedance tomography (EIT), different currents are applied to electrodes on the surface of an object and the resulting voltages are measured. The image of impedance (resitivity, conductivity) distribution or changes in the object is reconstructed based on these boundary measurements. EIT is a functional imaging technique, which may reveal the physiological and pathological information by human body's impedance properties. The advantages such as the non-invasive modality and the relative low cost make EIT become a research hot in medical imaging. However, the image reconstruction in EIT is a high ill-posed, non-linear, inverse problem, and it becomes a key and difficult point in EIT. In dynamic EIT, the image of impedance changes in the object is reconstructed. On the other hand, the image of impedance distribution in the object is reconstructed in static EIT, which is more difficult than in dynamic EIT. We study the reconstruction of static EIT in this paper, due to the static EIT has better clinical application prospect than the dynamic EIT.

Presently, non-invasive techniques are in vogue and preferred standard clinical approach because of its limitless advantages in monitoring real time phenomenon occurring within our human body without much interference. Many techniques such as ultrasound, magnetocardiography, CT scan, MRI etc., are used for real time monitoring but are generally not recommended for continuous monitoring. The limitations created by above used techniques are overcome by a proposed technique called non-invasive bio-impedance technique such as Electrical Impedance Technique (EIT). EIT imaging technique is based on internal electrical conductivity distribution of the body. The reconstruction of cross sectional image of resistivity required sufficient data collection by finite element method using MATLAB software. The EIT technique offers some benefits over other imaging modalities. It is economical, non-invasive, user friendly and emits no radiation thus appears to be one of the best fit technology for mass health care to be used by the basic health worker at a community level.

Magnetic induction tomography (MIT) is a tomographic technique capable of imaging the passive electromagnetic properties of an object. It has the advantages of being contact-less and non-invasive, as the process involves interrogating the electromagnetic field of the imaging subject. As such, the potential applications of MIT are broad, with various domains of operation including biomedicine, industrial process tomography and non-destructive evaluation. Consequently, there is a rich—yet underexplored—research landscape for the practical applications of MIT. The aim of this review is to provide a non-exhaustive overview of this landscape. The fundamental principles of MIT are discussed, alongside the instrumentation and techniques necessary to obtain and interpret MIT measurements.

Because of low resolution, Electrical Impedance Tomography (EIT) had been criticized by the experts and scholars. Although the resolution of the Magnetic Resonance Electrical Impedance Tomography (MREIT) which is combined EIT with Magnetic Resonance Imaging (MRI) technology and the resolution of the Magneto-Acoustic-Electrical Tomography (MAET) which is combined EIT with ultrasonic technology are improved, there are still existing problems, which are the electrode RF shielding in MREIT, the difficulty of further improving resolution in MAET. Combining the technologies of MRI and MAET for mutual advantage, this paper proposed a new method of Magnetic Resonance Motional-Electrical Tomography (MRMET) based on the principle of MAET. The software Comsol and Matlab were used to establish a two-dimensional simulation model, and the forward problem and inverse problem of MRMET were researched on the simulation works. The simulation results could reflect the conductivity distribution inside the simulation model, and MRMET could solve the problems of the EIT combination technologies.

Electrical resistance tomography (ERT) is well known as non-invasive imaging technique, inexpensive, radiation free, visualization measurements of the multiphase flows and frequently applied in geophysical, medical and Industrial Process Tomography (IPT) applications. Application of ERT in concrete is a new exploration field, which can be used in monitoring and detecting the health and condition of concrete without destroying it. In this paper, ERT model under the condition of concrete is studied in which the sensitivity field model is produced and simulated by using COMSOL software. The affects brought by different current injection values with different concrete conductivity are studied in detail. This study able to provide the important direction for the further study of inverse problem in ERT system. Besides, the results of this technique hopefully can open a new exploration in inspection method of concrete structures in order to maintain the health of the concrete structure for civilian safety.

Both computed tomography (CT) and positron emission tomography (PET) may be useful in addition to echocardiography and magnetic resonance (MR) imaging to study cardiac tumors. CT scan may be used as an alternative imaging modality in patients who cannot undergo MR because it is contraindicated or in patients already examined with other noninvasive methods without obtaining adequate images. High-speed equipments with electrocardiographic (ECG) gating can provide images with resolution

Since the 1980s, electrical tomographic imaging techniques based on low-frequency capacitance and resistance measurements have been developed for the monitoring of industrial processes and in some cases multiphase flows. Research on microwave tomography for oil and gas multiphase flow imaging began in the mid-1990s, even though the basic principle of microwave tomography was reported a decade earlier for biomedical imaging. In this paper, the development of a microwave tomographic imaging system for such an application since then is overviewed. It is shown by several examples that microwave tomography can effectively reconstruct the images of dielectric objects, moisture distribution inside processed food and oil–gas two-phase flows. It is also shown that the use of higher microwave frequencies would effectively lead to images of higher spatial resolution. Since real-time microwave tomography systems are currently available and ready for industrial applications, the challenges in developing a practical system with higher temporal resolutions suitable for the imaging of high speed multiphase flows in oil industry are highlighted and discussed in both hardware and image reconstruction aspects.

Research Article published by International Journal of Computer Applications Volume 101– No.8, September 2014

Multiphase flow characterization is an important task for monitoring, measuring or controlling industrial processes. This can be done by means of process tomography. The use of tomographic techniques has been used within the oil industry. One of the potential applications is flow visualization and measurement in producing wells. Research on industrial process tomography consists in obtaining estimated images of a cross section of a pipe or vessel containing or carrying the substances of the process. One category of process tomography is ultrasonic tomography technique. A simple tomography can be built by mounting a number of sensors around the circumference of a horizontal pipe. This includes acquiring and processing ultrasonic signals from the transducers to obtain the information of the spatial distributions of liquid and gas in an experimental column. Analysis on the transducers’ signals will be carrying out to distinguish between the observation time and the Lamb waves. The information obtained from the observation time is useful for further development of the image reconstruction. To obtain the time easily, the time will be calculated from the starting pulse of transmitter signal until the starting peak of receiver signal. Finally Support Vector Machine (SVM) was employed to distinguish of each phase between water and gas.

Process tomography (PT) techniques have been developed rapidly for visualizing the internal behavior of industrial processes, e.g. multi-phase flow measurement. Most of tomography systems employ a single measurement technique, such as computerized tomography (CT), optical tomography (OT), electrical resistance tomography (ERT) or electrical capacitance tomography (ECT). It is now possible to fit two or more tomographic systems to an industrial process. Detailed information from different modalities can be gained by inspection of separate tomographs, and the advantage of the strongest features provided by each unit can be taken. A combined tomogram can be produced of superior quality to any of the separate tomograms. To maximize the information available from the combined tomographic system, data fusion is the better option. In this paper, a dual-mode tomography system based on capacitance sensor and gamma sensor was developed to capture oil–gas two-phase flow. The two modalities can work at the same time. Two fusion methods, namely image fusion method and data fusion method, are proposed. Both simulation and static experiments for oil–gas two-phase flow were conducted. The reconstruction results of different fusion methods and modalities were compared and discussed.

X-ray luminescence and X-ray fluorescence computed tomography (CT) are two emerging technologies in X-ray imaging that provide functional and molecular imaging capability. Both emission-type tomographic imaging modalities use external X-rays to stimulate secondary emissions, either light or secondary X-rays, which are then acquired for tomographic reconstruction. These modalities surpass the limits of sensitivity in current X-ray imaging and have the potential of enabling X-ray imaging to extract molecular imaging information. These new modalities also promise to break through the spatial resolution limits of other in vivo molecular imaging modalities. This paper reviews the development of X-ray luminescence and X-ray fluorescence CT and their relative merits. The discussion includes current problems and future research directions and the role of these modalities in future molecular imaging applications.