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Purpose: The primary purpose of the study is to reconstruct the bladder based on the tomographic measurements obtained. Depending on the type of tomography used, two approaches are presented. Methods: In the first presented case, the measurements were collected using ultrasonic tomography, while in the second one, they were gathered with electrical impedance tomography. Deterministic methods and machine learning algorithms, such as Elastic Net, Least Angle Regression, and a Neural Network, were used to obtain the bladder reconstruction. Results: The bladder's position and size can be recognized based on the tomographic measurements of the UST and EIT. Both methods allow for its effective reconstruction. Discussion: The research results are satisfactory, but their effectiveness is debatable. Future studies will focus on comparing and optimizing both solutions regarding reconstruction time.

The article discusses the design of advanced embedded algorithms that aim to manage and control the measurement process using the Electrical Impedance Tomography and Ultrasonic Tomography methods. The project aims to develop solutions that optimize the performance of embedded devices that must operate on limited resources such as memory, computing power, or bandwidth. Minimizing energy consumption is an important aspect, especially for battery-powered devices. Algorithms must also be adapted to specific hardware constraints, such as low RAM or CPU limitations, which require complex engineering and optimization. Additionally, the project assumes the implementation of algorithms that consider security aspects, which is crucial in protecting data processed and transmitted by the device. It also requires the development of effective communication methods between the embedded device and other systems, including appropriate communication protocols.

Summary The main goal of the work was to develop a method for the fusion of images from two different measurement techniques. A project has been designed to integrate electrical impedance tomography (EIT) and ultrasonic tomography (UST) data. The next stage was to analyze the correlation between the EIT results and the occurrence of lower urinary tract dysfunctions and establish boundary parameters for visualization and segmentation. Additionally, the relationships between UST data and the dysfunctions were examined, which also required defining parameters for segmentation. The work also involves establishing standards and methods for the arrangement of measurement electrodes, which is crucial for the precision of both techniques. The proposed approach and results constitute an essential step towards implementing more advanced diagnostic tools to improve patient's quality of life by diagnosing lower urinary tract dysfunctions faster and more precisely.

The Greek marble statue of the Auriga of Mozia Island, in Sicily, is the most important artwork displayed at the Whitaker Foundation Archaeological Museum. It underwent geophysical investigations twice, in 2012 and 2021, to assess the marble’s degradation. The 2012 investigation prepared the statue for transfer to the Paul Getty Museum in New York and repositioning on an anti-seismic pedestal. The 2021 investigation evaluated potential new damage before another transfer. Both investigations utilized 3D ultrasonic tomography (UST) to detect degraded marble areas and ground-penetrating radar (GPR) to identify internal discontinuities, such as fractures or lesions, and locate metal pins that were previously inserted to reassemble the statue and its pedestal. Results from the UST indicate an average marble velocity of approximately 4700 m/s, suggesting good mechanical strength, with some areas showing lower velocities (~3000 m/s) within the material’s variability range. The GPR profiles demonstrated internal signal homogeneity, excluding internal fracture surfaces or lesions, and confirmed the presence of metallic pins. This study highlights the effectiveness of integrating UST and GPR for non-invasive diagnostics of marble sculptures, providing detailed insights into the marble’s condition and identifying hidden defects or damage.

High early strength (HES) concrete pavements are commonly opened to traffic within the first 24 h after construction, making early-opening decisions critical for pavement quality and traffic operations. Currently, most state departments of transportation rely on compressive strength testing for early-opening decision making. However, there laboratory tests are labor intensive, costly and not always representative of field strength development. In this study, non-destructive testing (maturity and ultrasonic tomography) was explored for faster and reliable in-situ strength estimations. An experimental section constructed using HES concrete was routinely monitored using compressive testing, maturity, and ultrasonic tomography in the first 24 h after construction. The shear wave velocity, measured using ultrasonic tomography, was able to capture the strength-gain variability within a single slab and between different slabs due to the ability to monitor several locations in a short period of time. Maturity results were consistently conservative in the first 24 h of monitoring. Results show that both maturity testing and ultrasonic tomography are able to replace or add to conventional strength testing for HES concrete pavements to facilitate making the opening decision within the first 24 h. Ultrasonic tomography proved more beneficial as a result of the device's portability, increased speed of testing, and accurate estimations of HES concrete strength for the entire pavement length.

Ultrasonic process tomography obtains the distribution of the two-phase flow based on ultrasound propagation in different fluids, thus is valuable to industrial monitoring and measurement. Ultrasonic process tomography can do a non-intrusively exploration of the multi-phase flow hydrodynamics. In this paper, a dual-mode ultrasonic process tomography is presented that fuses by reflection-mode tomography and time-of-flight ultrasonic tomography. In this method, a 32-digit array of ultrasonic sensors have been used for flow measurement. The two-phase flow rate that involves liquid and gas phases, have been calculated through a simple algebraic algorithm with obtained data from sensors. Simulation results depict that the measurement technique is independent of the fluid flow pattern and the system error also has been decreased. The invention of the article is about a simple algebraic method for image reconstruction which a special case is not considered in it and simultaneously, the image reconstruction error has been reduced. The relative error of the reconstructed images is presented by MATLAB simulation and it is much lower than the conventional methods. For a gas bubble with ultrasonic wave reflection time from its surface, the simulation results depict the SIE factor is less than 2%.

This paper presents the design and development of a high-resolution 3D ultrasound imaging system based on a 1 × 256 piezoelectric ring array, achieving an accuracy of 0.1 mm in both ascending and descending modes. The system achieves an imaging spatial resolution of approximately 0.78 mm. A 256 × 32 cylindrical sensor array and a digital phantom of breast tissue were constructed using the k-Wave toolbox. The signal is acquired layer by layer using 3D acoustic time-domain simulation, resulting in the collection of data from each of the 32 layers. The 1 × 256 ring array moves on a vertical trajectory from the chest wall to the nipple at a constant speed. A data set was collected at intervals of 1.5 mm, resulting in a total of 32 data sets. Surface rendering and volume rendering algorithms were used to reconstruct 3D ultrasound images from the volume data obtained via simulation so that the smallest simulated reconstructed lesion had a diameter of 0.3 mm. The reconstructed three-dimensional image derived from the experimental data exhibits the contour of the breast model along with its internal mass. Reconstructable dimensions can be achieved up to approximately 0.78 mm. The feasibility of applying the system to 3D breast ultrasound imaging has been demonstrated, demonstrating its attributes of resolution, precision, and exceptional efficiency.

The critical (design) parameters to be controlled for concrete pavements construction, in addition to the concrete strength, are slab`s thicknesses and doweled bars position at contraction joints, as they affect hugely structural performance, and, if not properly built may cause early ruptures. Construction compliance of such parameters is nowadays assessed through nondestructive techniques (NDT), such as ultrasonic low-frequency waves. Alignments of inserted doweled bars at contraction joints are analyzed herein for actual slabs as well as how thickness affects such position. Tests were carried out over an airport hangar apron after it has been built. Twenty-five concrete slabs were assessed using ultrasonic tomography allowing to verify disconformities of thicknesses and bars vertical and horizontal misalignments, with fair accuracy on measuring deviation angles of bars.

A new versatile and geometrically reconfigurable ultrasonic tomography system (UTS) has been designed to inspect and obtain information about the internal structure and inner damage of columns in heritage buildings. This nondestructive system is considered innovative because it aims to overcome common limitations of existing systems. Tomographic inspections are typically carried out manually and are thus limited to small portions of construction elements. The proposed UTS allows the automatization of the inspection and the generation of numerous tomographic slices along the height of the column. It is valid for multiple types of columns and materials. In the present work, the system was tested on two limestone columns of the north façade of the Convent of Carmo in Lisbon, Portugal. The UTS is composed of a mechanical and an electronic system. The mechanical system consists of four linear motion subsystems mounted in a square setup. A transducer is placed on each of the axes, acting as emitter or receiver of the ultrasonic signals. The mechanical system also includes a guide system to adapt the inspections to the complex geometry of the columns. The electronic system allows the control and the synchronization of the movements and the emission/reception configuration of the four ultrasonic transducers.

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.

Abstract The authors are trying to develop an ultrasonic CT technique for concrete structures. As the first step of its development, we study how the ultrasonic waves propagate in concrete structures and pose a problem to develop ultrasonic CT, applying which we give a non-destructive inspection technique for concrete cover by application of the idea of the ultrasonic CT. The authors claim that this study gives the foundation of the theory of ultrasonic CT for concrete structures.

Abstract Ultrasonic tomography (UT) is a non-invasive multiphase flow detection technique. In ultrasonic transmission tomography, reconstruction images are derived from a direct wave signal transmitted through the materials in the sensing area. The maximum values of the received direct wave from the reference pattern and the measured pattern are normally used to reconstruct the images. The speed of sound in the pipe wall and the materials in the sensing area affect the received signal. This in turn affects image quality—especially when the arrival time of the direct wave propagated through the sensing area is close to the arrival time of the direct wave propagated through the pipe wall. Here, we describe a novel shielding structure for ultrasonic transmission tomography. The relative variation ratio (RVR) is defined and used to evaluate the validity of the shielding structure. Larger RVR values imply better signal resolution and better signal suppression. A simplified mode is discussed including the influence of the shielding structure’s design parameters on the received direct wave. The optimized shielding structure size was determined. A comparison of the results between the normal pipe and the shielding pipe indicated that the RVR increased from 57.25 to 91.27%. This proves that the shielding structure can suppress the effect of the signal from the pipe wall on received direct wave signals.

Abstract In recent years, due to the destructive and unproductive character of pavement specimen extraction, pavement maintenance technology intensified the use of non-destructive techniques for pavement evaluation which resulted in the development of several devices and evaluation methods. This paper describes the use of technology based on low frequency ultrasonic tomography for evaluation of concrete pavement parameters. The equipment was applied in three experimental sections with different concrete pavements built at the University of Sao Paulo campus. The ultrasonic signal processing is given. The results analysis enables the efficient and reliable identification of thickness and reinforcement position within the concrete slab. Construction problems were evidenced in one of experimental sections with thickness deficiencies and reinforcement in a position below projected. Furthermore, the use of a novel concrete quality indicator was correlated with the presence of transverse cracks and alkali-silica reaction within the sections.

ObjectivesWe propose an automatic breast mass detection algorithm in three-dimensional (3D) ultrasound (US) images using the Hough transform technique.MethodsOne hundred twenty-five cropped images containing 68 benign and 60 malignant masses are acquired with clinical diagnosis by an experienced radiologist. The 3D US images are masked, subsampled, contrast-adjusted, and median-filtered as preprocessing steps before the Hough transform is used. Thereafter, we perform 3D Hough transform to detect spherical hyperplanes in 3D US breast image volumes, generate Hough spheres, and sort them in the order of votes. In order to reduce the number of the false positives in the breast mass detection algorithm, the Hough sphere with a mean or grey level value of the centroid higher than the mean of the 3D US image is excluded, and the remaining Hough sphere is converted into a circumscribing parallelepiped cube as breast mass lesion candidates. Finally, we examine whether or not the generated Hough cubes were overlapping each other geometrically, and the resulting Hough cubes are suggested as detected breast mass candidates.ResultsAn automatic breast mass detection algorithm is applied with mass detection sensitivity of 96.1% at 0.84 false positives per case, quite comparable to the results in previous research, and we note that in the case of malignant breast mass detection, every malignant mass is detected with false positives per case at a rate of 0.62.ConclusionsThe breast mass detection efficiency of our algorithm is assessed by performing a ROC analysis.

Based on the results of preoperative examination in 180 patients, the investigators studied and analyzed the specific features of ultra- sonic images of endometrial cancer in detail. The comprehensive study comprising color Doppler and energy mapping, three-dimen- sional echography with standard and variable-frequency transducers was conducted using the expert-class ultrasound equipment. A close analysis revealed the high informative value of complex ultrasonic tomography in the preoperative staging of cancer of the cor- pus uteri, in its early stages in particular.

X-ray tomography and magnetic resonance imaging (MRI) are excellent techniques for non-destructive or non-invasive inspections, however, they have shotcomings including the expensive cost in both the devices themselves and their protection facilities, the harmful side effects of the X-rays to human bodies and to the environment. In view of this argument, it is necessary to develop new, inexpensive, safe and reliable tomographic techniques, especially in medical imaging and non-destructive inspections. There are new tomographic techniques under development such as optical tomography, photo-acoustic tomography, ultrasonic tomography and so on, from which we take ultrasonic tomography as the topic in this paper. We introduce a review of the known ultrasonic tomographic techniques and discuss their future development.

The paper presents a methodology for comprehensive use of ultrasonic tomography and impact-echo – the state-of-the-art acoustic techniques – for non-destructive identification of the thickness of unilaterally accessible concrete elements. Since the techniques are not commonly used, they are little known. Therefore, a brief description of the techniques is given to facilitate the understanding of the subsequently presented methodology. The article gives a practical example of the use of the methodology, which demonstrates its suitability for non-destructive identification of the thickness of concrete elements, particularly those only accessible from one side. In the example, the concrete shell of a heat pipe, carrying tunnel located under a river was tested using the ultrasonic tomography and impact-echo techniques. The tests were carried out according to the proposed methodology. It should be noted that the test results yielded by the two methods were similar. In this way, the proposed methodology has been validated.