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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.

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.

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 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 (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%.

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.

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.

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.

The image of the current non-destructive testing system using a high energy accelerator is limited to conventional two-dimensional metaphysical information. Requirements for the present manufacturing industry are growing rapidly and include quantitative measurements, high-density component model extraction, reverse process development and precision inspection to meet the needs for the verification of manufactured goods. Therefore, industrial three-dimensional high-penetration tomography has emerged as the most promising method. In this study, in order to evaluate the applicability of a MeV-level high-energy accelerator, we developed a three-dimensional tomography system using a 450 kV X-ray generator. Evaluation of the three-dimensional tomography image is based on measurements of the penetration and the image resolution for high-energy X-rays.

This paper presents an investigation on the use of tomography system using using optical and electrodynamic sensors. The system obtains data from both sensors which detect the flow in a process pipe. Information on the flow is processed in order to display the image reconstruction of a solid flow.

Electromagnetic tomography (EMT) is a recent imaging technique. Its purpose is to determine the distribution of electrical conductivity and magnetic permeability in a given region of interest. EMT is based on the principle of electromagnetic induction. This distribution is computed from the measurements of the induced voltages at several coils placed around the region which are produced by the application of different excitation patterns . Usually images are obtained through inversion of the projection data. The paper represents a fundamental investigation of the potential of using electromagnetic measurements for industrial tomography application. This paper concentrates on image reconstruction of either electrically conducting material or magnetically permeable materials. Finally a number of potential industrial applications for the EMT technique are discussed.

Measurement and visualization of the fracture process zone (FPZ) in the silicate composites is essential for understanding how the crack is formed and how it is propagating through the material. Although several time-lapse radiography and tomography experiments during the three-point bending of silicate composites with conventional imaging techniques have been already realized, the crack initiation and propagation is so fast process, that it is very difficult to capture sufficient spatial information in the exact moment when this process is occurring. Nowadays progress in X-ray imaging instrumentation, especially single photon counting CdTe detectors with a fast parallel readout, allows speeding up the acquisition of the tomographic data while keeping the intrinsic resolution of tens of micrometers and high efficiency even for photons with higher energy. Tomography of relatively fast processes is becoming realistic even in laboratory conditions using commercially available microfocus X-ray tubes. As an example of such a fast tomography, results of “on-the-fly” series of tomographic experiments performed on the specimen subjected to continual three-point bending test is presented.

Infrared thermal imaging based on active thermal excitations has been widely used for nondestructive evaluation (NDE) of materials. While the experimental systems have remained essentially the same during the last few decades, development of advanced data-processing methods has significantly improved the capabilities of this technology. However, many limitations still exist. One fundamental limitation is the requirement, either explicitly or implicitly, of the tested material to be homogeneous such that detected thermal contrasts may be used to determine an average material property or attributed to flaws. In this paper, a new thermal tomography (TT) method is introduced, which for the first time can evaluate heterogeneous materials by directly imaging their thermal-property variations with space. It utilizes one-sided flash thermal-imaging data to construct the three-dimensional (3D) distribution of thermal effusivity in the entire volume of a test sample. Theoretical analyses for single and multilayer material systems were conducted to validate its formulation and to demonstrate its performance. Experimental results for a ceramic composite plate and a thermal barrier coating (TBC) sample are also presented. It was shown that thermal diffusion is the primary factor that degrades the spatial resolution with depth for TT; the spatial resolutions in the lateral and axial directions were quantitatively evaluated.

Ring artifacts have been studied for X–ray based Computed Tomography (CT) systems but not on γ-ray based in-situ applications. This paper discusses application of recently proposed automatic ring artifact reduction method (Yoon et al., 2016) on previously obtained experimental projection data from a γ-ray based Industrial Process Tomography (IPT) system for a prototype catalytic column. Studies include qualitative and quantitative evaluation of the method. It is observed that ring artifacts are suppressed without loss of significant information in γ-ray PT images.

In this introduction article, we present a brief overview of industrial process tomography. This will start by linking between the concept of industrial process tomography and super-sensing. This will follow with a brief introduction to various process tomography systems and in particular electrical tomography methods. This article is part of the themed issue ‘Supersensing through industrial process tomography’.

Magnetic induction tomography (MIT) is a new and emerging tomographic imaging technique, which has found applications in industrial process tomography and material inspection, particularly for imaging metallic objects. In this paper, a rotational MIT (RMIT) system has been developed, in which a coil array is rotated with respect to a central axis perpendicular to the plane of the coil array. The RMIT is capable of producing images with better quality as a result of increasing the number of independent measurements. An eight-coil MIT system has been developed to generate the experimental data required in this paper. To show the proof of principle, a manual rotational scheme has been implemented. The advantages of the RMIT system have been established using theoretical analysis and comparison of the underlying inverse problem in MIT and RMIT. The effectiveness of RMIT has been shown using both synthetic and experimental data. Several image quality measures have been used to critically evaluate RMIT against the traditional MIT system.

Magnetic Induction Tomography (MIT) is a new and emerging type of tomography technique that is able to map the distribution of all three passive electromagnetic properties, however most of the current interests are focusing on the conductivity and permeability imaging. In an MIT system, coils are used as separate transmitters or sensors, which can generate the background magnetic fleld and detect the perturbed magnetic fleld respectively. Through switching technique the same coil can work as transceiver which can generate fleld at a time and detect the fleld at another time. Because magnetic fleld can easily penetrate through the non-conductive barrier, the sensors do not need direct contact with the imaging object. These non-invasive and contactless features make it an attractive technique for many applications compared to the traditional contact electrode based electrical impedance tomography. Recently, MIT has become a promising monitoring technique in industrial process tomography, for example MIT has been used to determine the distribution of liquidised metal and gas (high conductivity two phase ∞ow monitoring) for metal casting applications. In this paper, a low conductivity two phase ∞ow MIT imaging is proposed so the reconstruction of the low contrast samples (< 6S/m) can be realised, e.g., gas/ionised liquid. An MIT system is developed to test the feasibility. The system utilises 16 coils (8 transmitters and 8 receivers) and an operating frequency of 13MHz. Three difierent experiments were conducted to evaluate all possible situations of two phase ∞ow imaging: 1) conducting objects inside a non-conducting background, 2) conducting objects inside a conducting background (low contrast) and 3) non-conducting objects inside a conducting background. Images are reconstructed using the linearised inverse method with regularisation. An experiment was designed to image the non-conductive samples inside a conducting

Magnetic Induction Tomography (MIT) is a relatively new and emerging type of tomography techniques that is able to map the distribution of all three passive electrical properties (PEPs). Its non-invasive and contactless features make it an attractive technique for many applications compared to the traditional contact electrode based electrical impedance tomography. Recently, MIT has become a promising monitoring technique in industrial process tomography, and the area of the research interest has moved from 2D to 3D because of the volumetric nature of electromagnetic field. Three dimensional MIT images provide more information on the conductivity distribution, especially in the axial direction. However, it has been reported that the reconstructed 3D images can be distorted when the imaging object is located at a less sensitive region. Although this distortion can be compensated by adjusting the regularisation criteria, this is not practical in real life applications as the prior information about the object's location is often unavailable. This paper presents a memory efficient 4D MIT algorithm which can maintain the image quality under the same regularisation circumstances. Instead of solving each set of measurement individually, the 4D algorithm takes advantage of the correlations between the image and its neighboring data frames to reconstruct 4D of conductivity movements. The 4D algorithm improves the image qualities by increasing the temporal resolution. It also overcomes some sensitivity issues of 3D MIT algorithms and can provide a more stable result in terms of the size consistency of the reconstructed image. Several experimental results using real laboratory data are presented for validating the proposed algorithms.

Imaging logging is a new technique which has been developing in recent years, its’ silo facilities could collect large information with high resolution, and the measurement result is usually presented in graphics after processed. This paper presents a new imaging logging technique based on magnetic-acoustic Tomography with Magnetic Induction(MAT-MI), introduces its’ logging principle, gives detailed experimental system, makes a simple copper coil experiment and verifies the feasibility of the technique. These studies will lay a foundation for practical application of new imaging logging technology.

Gamma-ray computed tomography (CT) is a powerful non-invasive imaging technique for viewing an object in 2-D or 3-D cross-section images without the need to physically section it. The invention of CT technique revolutionised the field of medical diagnostic imaging because it provides more detailed and useful information than any previous non-invasive imaging technique. The method is increasingly used in industrial fields. This paper describes the development of a gamma-ray computed tomography system for imaging and visualising of industrial multiphase reactors. The theoretical aspects of CT scanner, the system configurations and the adopted algorithm for image reconstruction are discussed. Penetrating radiation from an isotopic gamma-ray source of Cs-137 and a bank of NaI(Tl) scintillation detectors in combination with a dedicated mechanical gantry set-up were used to construct the CT system. During scanning, the movement of the detector’s bank and rotation table is controlled by a LabView-based software. The software is also designed to control all associated nuclear electronics equipments and finally to acquire gamma-ray transmission data. The image reconstruction is performed by using Expectation-Maximisation (EM) and Alternating-Maximisation (AM) algorithms written in Visual-Fortran programming language. Several physical phantoms to simulate industrial multiphase process columns and reactors were scanned using this CT scanner. Some of the reconstructed images are presented in this paper.

The tomographic imaging of process parameters for oil-gas-water three-phase flow can be obtained through different sensing modalities, such as electrical resistance tomography (ERT) and electrical capacitance tomography (ECT), both of which are sensitive to specific properties of the objects to be imaged. However, it is hard to discriminate oil, gas and water phases merely from reconstructed images of ERT or ECT. In this paper, the feasibility of image fusion based on ERT and ECT reconstructed images was investigated for oil-gas-water three-phase flow. Two cases were discussed and pixel-based image fusion method was presented. Simulation results showed that the cross-sectional reconstruction images of oil-gas-water three-phase flow can be obtained using the presented methods.

Electrical impedance tomography (EIT) noninvasively creates images of the local ventilation and arguably lung perfusion distribution at bedside. Methodological and clinical aspects of EIT when used as a monitoring tool in the intensive care unit are reviewed and discussed.Whereas former investigations addressed the issue of validating EIT to measure regional ventilation, current studies focus on clinical applications such as detection of pneumothorax. Furthermore, EIT has been used to quantify lung collapse and tidal recruitment in order to titrate positive end-expiratory pressure. Indicator-free EIT measurements might be sufficient for the continuous measurement of cardiac stroke volume, but assessment of regional lung perfusion presumably requires the use of a contrast agent such as hypertonic saline.Growing evidence suggests that EIT may play an important role in individually optimizing ventilator settings in critically ill patients.

As a rather new technology, X-Ray Computed Tomography offers new and promising possibilities in manufacturing metrology in comparison to well-established tactile or optical measurements. The main benefit is the volumetric model which results of each measurement and represents the measurement object holistically with high point density.