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Objective: We explored the use of ultrasonography in determining the minimal transverse diameter of the subglottic airway (MTDSA) for the purpose of choosing an appropriate model of reinforced cuffed endotracheal tube. Methods: A total of 110 pediatric patients who received general anesthesia and tracheal intubation for selective surgeries at the hospital from February 2019 to February 2022 were chosen. They were then randomly assigned to three groups: 39 in the MTDSA group, 35 in the age formula group, and 36 in the height formula group. We assessed how accurately the appropriate endotracheal tube model was predicted in each group and compared their predictive performance. Results: The age range of the enrolled pediatric patients was 3–6 years old. The ultrasonic measurement method demonstrated a prediction accuracy of 87.18%, while the age formula method and height formula method exhibited lower accuracy rates of 54.29% and 47.22%, respectively. Notably, the ultrasonic measurement method outperformed the other two methods significantly (P < 0.05). In the MTDSA group, 2 patients had their catheters changed during anesthesia, and the proportion of patients who changed their catheters was 5.13%. In the MTDSA group, 6 catheters were replaced, and the frequency of catheter replacement was 15.38%. In contrast, these percentages were much higher in the age formula group, at 31.43% and 45.71%, and in the height formula group, at 36.11% and 52.78%. The latter two groups had significantly higher values than the MTDSA group (P < 0.05). Regarding complications such as hoarseness, laryngeal edema, aspiration, and laryngospasm, the MTDSA group experienced a notably lower total incidence of 7.69% compared to the 37.14% in the age formula group and 41.67% in the height formula group, demonstrating statistical significance (P < 0.05). Conclusion: The ultrasonic measurement technique employed in MTDSA exhibits impressive precision when it comes to forecasting the specific model of a reinforced cuffed endotracheal tube for pediatric patients. This enhanced accuracy contributes significantly to minimizing the need for tube replacements during anesthesia and the associated complications. It holds immense importance in assisting clinicians in selecting the most appropriate pediatric endotracheal tube model for anesthesia induction. [ABSTRACT FROM AUTHOR]

This article presents an overall examination of how small temperature fluctuations affect P-wave velocity (Vp) measurements and their uncertainties in concrete using embedded piezoelectric transducers. This study highlights the fabrication of custom transducers tailored for long-term concrete monitoring. Accurate and reliable estimation of ultrasonic wave velocities is challenging, since they can be impacted by multiple experimental and environmental factors. In this work, a reliable methodology incorporating correction models is introduced for the quantification of uncertainties in ultrasonic absolute and relative velocity measurements. The study identifies significant influence quantities and suggests uncertainty estimation laws, enhancing measurement accuracy. Determining the onset time of the signal is very time-consuming if the onset is picked manually. After testing various methods to pinpoint the onset time, we selected the Akaike Information Criterion (AIC) due to its ability to produce sufficiently reliable results. Then, signal correlation was used to determine the influence of temperature (20 °C to 40 °C) on Vp in different concrete samples. This technique proved effective in evaluating velocity changes, revealing a persistent velocity decrease with temperature increases for various concrete compositions. The study demonstrated the capability of ultrasonic measurements to detect small variations in the state of concrete under the influence of environmental variables like temperature, underlining the importance of incorporating all influencing factors. [ABSTRACT FROM AUTHOR]

Contact stiffness–contact stress mapping relationship is the key to ultrasonic stress measurement. The interaction of asperities at the rough interface is very complicated. The complexity of the asperity interaction and the irregularity of the lubricant film distribution make it difficult for the existing acoustic models to accurately construct the mapping relationship. Therefore, this paper conducts experimental research on the contact stiffness of the lubricating interface, and constructs the contact stiffness–contact stress mapping relationship of the lubricating interface considering the influence of plastic deformation. The critical contact pressure is determined and used to analyze the influence of plastic deformation and elastic deformation on contact stiffness. The change of equivalent oil film thickness and stiffness under load was also analyzed, and the optimized analysis formula is obtained. Based on the load sharing concept, the contact stiffness–contact stress mapping relationship of lubricating interface was constructed. Finally, the proposed acoustic model was experimentally verified. [ABSTRACT FROM AUTHOR]

The interplay between the internal mechanical properties and external mechanical conditions of a battery cell, e. g., Young's modulus and thickness change, has a crucial impact on the cell performance and lifetime, and thus, needs to be fully understood. In this work, 12 Ah lithium‐ion battery pouch cells were studied during cycling and aging by non‐invasive operando ultrasonic and dilation measurements. The effective Young's modulus increases and the thickness varies the most within a single cycle during the graphite transition from stage 1L to 4, at the beginning of the 2 to 1 stage transition and at the phase transition of the nickel‐rich NCM from H2 to H3. After 1000 cycles of aging, the overall effective Young's modulus of the lithium‐ion battery decreases by ∼11 %–12 % and the cell thickness increases irreversibly by ∼3 %–4 %, which is mostly related to a thicker and possibly softer, more porous solid electrolyte interphase layer. [ABSTRACT FROM AUTHOR]

Piezoelectric transducers are widely used for generating acoustic energy, and choosing the right radiating element is crucial for efficient energy conversion. In recent decades, numerous studies have been conducted to characterize ceramics based on their elastic, dielectric, and electromechanical properties, which have improved our understanding of their vibrational behavior and aided in the manufacturing of piezoelectric transducers for ultrasonic applications. However, most of these studies have focused on the characterization of ceramics and transducers using electrical impedance to obtain resonance and anti-resonance frequencies. Few studies have explored other important quantities such as acoustic sensitivity using the direct comparison method. In this work, we present a comprehensive study that covers the design, manufacturing, and experimental validation of a small-sized, easy-to-assemble piezoelectric acoustic sensor for low-frequency applications, using a soft ceramic PIC255 from PI Ceramic with a diameter of 10 m m and a thickness of 5 m m. We present two methods, analytical and numerical, for sensor design, followed by experimental validation, allowing for a direct comparison of measurements with simulated results. This work provides a useful evaluation and characterization tool for future applications of ultrasonic measurement systems. [ABSTRACT FROM AUTHOR]

This work proposes the slope of the phase spectrum as a signal processing parameter for the ultrasonic monitoring of the water content of water-in-crude oil emulsions. Experimental measurements, with water volume fractions from 0 to 0.48 and test temperatures of 20 °C, 25 °C, and 30 °C, were carried out using ultrasonic measurement devices operating in transmission–reception and backscattering modes. The results show the phase slope depends on the water volume fraction and, to a lesser extent, on the size of the emulsion droplets, leading to a stable behavior over time. Conversely, the behavior of the phase slope as a function of the volume fraction is monotonic with low dispersion. Fitting a power function to the experimental data provides calibration curves that can be used to determine the water content with percentage relative error up to 70% for a water volume fraction of 0.06, but less than 10% for water volume fractions greater than 0.06. Furthermore, the methodology works over a wide range of volume fractions. [ABSTRACT FROM AUTHOR]

Unmanned aerial vehicles (UAVs) are seeing increasing adoption to automated remote and in situ inspection of industrial assets, removing the need for hazardous manned access. Aerial manipulator architectures supporting pose-decoupled exertion of force and torque would further enable UAV deployment of contact-based transducers for sub-surface structural health assessment. Herein, for the first time, we introduce an over-actuated multirotor deploying a dry-coupled ultrasonic wheel probe as a novel means of wall thickness mapping. Using bi-axial tilting propellers in a unique tricopter layout, this system performs direct thrust vectoring for efficient omnidirectional flight and application of interaction forces. In laboratory testing, we demonstrate stable and repeatable probe deployment in a variety of representative asset inspection operations. We obtain a mean absolute error (MAE) in measured thickness of under 0.10 mm when measuring an aluminum sample with varying wall thickness. This is maintained over repeated exit and reentry of surface contact and when the sample is mounted vertically or on the underside of a 45° overhang. Furthermore, when rolling the probe dynamically across the sample surface in an area scanning modality, an MAE in wall thickness below 0.28 mm is recorded. Multi-modal operational confidence bounds of the system are thereby quantitatively defined. Note to Practitioners—Motivation for this article stems from the desire to enhance the speed and level of insight into structural health currently offered through remote aerial inspection processes. We approach this by integration of a thrust vectoring multirotor platform with a dry-coupling wheel probe for aerial ultrasonic thickness measurement. This system reliably presses the probe into the target surface and obtains point measurements across various surface orientations without a stabilizing frame. This broadens applicability and permits novel inspections where couplant gel would otherwise contaminate the surface and require manual cleaning. We profile thickness along a scanned linear section, a mode suited to corrosion mapping of large surface areas such as petrochemical storage tanks, pipework, or similar assets. We also make detailed consideration toward measurement accuracy, repeatability, and localization, an aspect commonly overlooked in literature. Future work to characterize variable friction effects currently limiting rolling scan speed and measurement coverage density may be beneficial. Quantitative study of the effectiveness of dry-couplant in the presence of any uncommon surface contaminants specific to a desired use-case is also advised. [ABSTRACT FROM AUTHOR]

Guided acoustic waves are commonly used in domestic water meters to measure the flow rate. The accuracy of this measurement method is affected by factors such as variations in temperature and limescale deposition inside of the pipe. In this work, a new approach using signals from different sound propagation paths is used to determine these quantities and allow for subsequent compensation. This method evaluates the different propagation times of guided Lamb waves in flow measurement applications. A finite element method-based model is used to identify the calibration curves for the device under test. The simulated dependencies on temperature and layer thickness are validated by experimental data. Finally, a test on simulated data with varying temperatures and limescale depositions proves that this method can be used to separate both effects. Based on these values, a flow measurement correction scheme can be derived that provides an improved resolution of guided acoustic wave-based flow meters. [ABSTRACT FROM AUTHOR]

Copyright of Technisches Messen is the property of De Gruyter and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Lubrication is essential in metal cold rolling operation to regulate friction at the metal–roll interface, reduce energy loss and improve the product surface finish. A novel non-intrusive pitch-catch technique, based on the reflection of ultrasound, was employed on a pilot mill to evaluate oil-film thickness at the metal–roll interface during the metal cold rolling operation. During the metal rolling process, oil-film thickness was measured under varying rolling load and rolling speed. The oil-film thickness increases as the roll speed increases and reduces as the rolling load increases. The values of oil-film thickness obtained from this non-intrusive ultrasonic technique agree with theoretical values. This study is a proof of concept and has shown promising results. If further developed, the technique could be employed for in situ monitoring of lubricant during rolling operation in metal rolling industries. [ABSTRACT FROM AUTHOR]

The presented paper deals with the development of a new method for determining static and dynamic values of mechanical equivalents from ultrasonic wave measurements. The aim of the new method of determination of mechanical equivalents of materials based on ultrasonic wave measurements is the development of a new algorithm for implementation in instruments for express non‐destructive diagnostics of elastic‐strength and defectoscopic parameters and instantaneous stress‐strain state of the material, including theoretical construction of the σ‐ϵ load diagram and other analyses based on ultrasonic measurements. The proposed method is characterized by a new theoretical basis for determining the equivalents of physical‐mechanical and defectoscopic characteristics, i. e., the equivalents of the so‐called tabular values of materials, and, in addition, it will also expressively evaluate their time evolution changes due to the structural‐strain alteration of the material during the reshaping process under technological and functional stresses. [ABSTRACT FROM AUTHOR]

Ultrasonic backscatter techniques may offer a useful approach for detecting changes in bone caused by osteoporosis. The goal of this study was to investigate how bone mineral density (BMD) and the microstructure of human cancellous bone affect three ultrasonic backscatter parameters that have been identified as potentially useful for ultrasonic bone assessment purposes: the apparent integrated backscatter (AIB), the frequency slope of apparent backscatter (FSAB), and the frequency intercept of apparent backscatter (FIAB). Ultrasonic measurements were performed with a 3.5-MHz broadband transducer on 54 specimens of human cancellous bone prepared from the proximal femur. Microstructural parameters and BMD were measured using X-ray microcomputed tomography (micro-CT). Relationships between AIB, FSAB, FIAB, and the micro-CT parameters were investigated using univariate and multivariate statistical analysis techniques. Moderate-to-strong univariate correlations were observed between the backscatter parameters and microstructure and BMD in many cases. The partial correlation analysis indicated that the backscatter parameters are dependent on microstructure independently of BMD in some cases. Multiple stepwise linear regression analysis used to generate multivariate models found that microstructure was a significant predictor of the backscatter parameters in most cases. [ABSTRACT FROM AUTHOR]

Copyright of China Sciencepaper is the property of China Sciencepaper and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this article, we present a Doppler-effect-compensated ranging system that can be applied to subcentimeter-precision ultrasonic distance measurement for moving targets using a direct sequence spread spectrum (DSSS). First, the theory of the Doppler compensation technique is explained, and then, the evaluation results obtained using maximum-length-sequence coded ultrasonic signals are discussed. In this study, we employ a 128-b DSSS code with three wavelengths per bit. The experimental results demonstrate that the proposed system can measure a target accelerating at 9.8 m/s2 with a speed of up to 2 m/s in the range of 0.1–1.6 m, with a standard deviation of less than 5 mm. We also confirmed by simulation that the system can track a target accelerating at 30 m/s2 with a speed of up to 5.5 m/s in the range of 4–6 m. [ABSTRACT FROM AUTHOR]

Objective: To investigate the association of several obesity anthropometric indices, including body mass index (BMI), waist circumference (WC) and waist-hip ratio (WHR), with carotid intima media thickness (CIMT) in local Chinese population; and to examine the variation of CIMT with age in local Chinese population. Methods: This is a cross-sectional prospective study in 184 Chinese patients in a local Accident and Emergency Department (AED) aged ≥ 18 years without risk factors for atherosclerosis. Subjects’ common carotid artery intima media thickness was measured with a 4.5-15MHz linear ultrasound transducer at a point 10mm proximal to the carotid bulb. All subjects’ age, gender, anthropometric (WC and hip circumference (HC) from which WHR was calculated, weight and height from which BMI was calculated) and CIMT values were recorded on a pro forma. Descriptive and inferential statistic methods such as t test and chi-square were carried out. Correlation coefficients were used to determine the relationship between age, BMI, WC, WHR, and CIMT. Results: The right, left, and average CIMT of both sides in our study subjects were 0.55+/-0.14mm, 0.58+/- 0.15mm, and 0.56+/-0.14mm respectively, with no significant difference between the right and left sides (p>0.05). The left, right and average CIMT did not differ significantly between men and women (p>0.05). WC (r=0.313, 0.271, 0.309; all p<0.001) and WHR (r=0.359, 0.312, 0.355; all p<0.001) showed moderate positive correlations with right, left, and average CIMT. BMI (r=0.188, 0.160, 0.184; p<0.05) showed weak positive correlations with right, left, and average CIMT. Correlations between BMI with right, left, and average CIMT in male was found to be stronger than in female. There was a linear relationship between age and CIMT (r=0.557, 0.509, 0.564 for right, left and average CIMT respectively; all p<0.001), for which in female was stronger than in male. Conclusions: Ultrasonic CIMT measurement can be useful for refining CVD risk assessment in some symptomatic patients. It detects subclinical vascular disease and identifies patients at increased risk of CVD, and thus aids in risk stratification and patient management especially in the primary care setting and AED. This study provides evidence of a positive association of WC, WHR, BMI and age with CIMT in Hong Kong Chinese population. The association of WC and WHR was found to be stronger than that of BMI with CIMT. WC and WHR may be used as supplemental indices for redefining obesity and an alternative tool for further refining discrimination of early atherosclerotic burden. CIMT increases with age, and this factor should be considered in the sonographic assessment of CIMT. [ABSTRACT FROM AUTHOR]

Ultrasonic Echo Method – Deriving structural parameters from measured values Non‐destructive testing methods provide valuable information for the assessment of structures. The application of these methods facilitates the measurement of material properties and the description of the structureś inside geometry. The internal structure is usually examined non‐destructively using volume methods. The ground penetration radar (GPR) method and the ultrasonic echo technique are important tools. Their application requires one‐sided accessibility to the component only. Various testing tasks can be solved, e. g. the localization of reinforcement or tendon ducts, the determination of the thickness of components or the detection of structural defects. In this study it is shown how measurement results, suitable to be used later in engineering assessments, can be derived from observations made with ultrasonic echo measurements. The testing method and the measuring system are explained first. Subsequently, the procedure starting with the evaluation of the measurement signals via the calculation of the measurement uncertainty up to the determination of the characteristic material parameters is shown. Finally, the methodology is demonstrated on a reference specimen made of Polyamide. The findings are compared with the results of measurements on concrete. [ABSTRACT FROM AUTHOR]

Background: Ultrasonic measurement has not been utilized to assess the functional recovery of transplanted muscle. This study aimed to investigate the feasibility of using B-ultrasound measurement to assess muscle recovery following free functioning gracilis transfer. Methods: From January 2009 to January 2014, 35 patients receiving free functioning gracilis transfer to treat total brachial plexus injury were enrolled. B-ultrasound was adopted to determine the cross-sectional area (CSA) of transplanted gracilis muscle at rest and contraction state. The ratio of pre- to post-transplant CSA value at rest state was defined as muscle bulk ratio (MBR). The ratio of CSA value at contraction state to rest state was defined as contraction ratio (CR). Results: Patients with muscle strength M ≥ 4 had significantly higher CR1 (post-transplant), CR2 (pre-transplant), and range of motion (ROM, joint mobility) than those with muscle strength M < 4. The CR1 > CR2 group had significantly higher CR1, muscle strength, and ROM than the CR1 ≤ CR2 group. The MBR > 1 group had significantly higher muscle strength than the MBR ≤ 1 group. CR1 value was highly correlated with muscle strength and with ROM. CR2 value was moderately correlated with muscle strength and ROM. Multivariate linear regression analysis showed that a higher CR1/CR2 value was associated with a higher muscle strength and joint mobility. The CR1 > CR2 group had better muscle strength and ROM than the CR1 ≤ CR2 groups. Conclusion: B-ultrasound measurement can quantitatively reflect muscle strength following gracilis transfer, and CR value could be a potential indicator for functional recovery of the transplanted gracilis muscle. Level of Evidence: Prognostic studies, Level II. [ABSTRACT FROM AUTHOR]

This study investigates the feasibility of the application of ultrasonic measurement to characterize Steel-Fiber-Reinforced Concrete (SFRC). Specifically, the effects of steel fiber content, age, moisture content, and fiber orientation on Ultrasonic-Pulse- Velocity (UPV) were investigated. In this regard, beam and cylindrical samples were fabricated with different steel fiber contents. The result indicated that for beam specimens the UPV increases with the addition of fiber up to 2% and decreases for higher fiber percentages. Additionally, the fiber orientation within the beam specimens influences the UPV measurements. For cylindrical samples, the rate of UPV decreased with the addition of steel fiber reinforcement. In addition, it was discovered that the curing period affects the magnitude of UPV. [ABSTRACT FROM AUTHOR]

The present study was conducted to determine eye muscle (M. Longissimus dorsi) properties of lambs from two genotypes. The depth, eye muscle area and eye muscle perimeter of Longissimus dorsi and thickness of fat covering this muscle using ultrasonic scan was determined using ultrasonic measurements from 118 lambs taken from the two different genotypes - 80 heads from Tsigai - rusty variety (40 female and 40 male) and 38 heads (30 female and 8 male) from Suffolk (50%) x German Blackface (37.5%) x Tsigai (12.5%). The animals were fed with different diets. Birth weight was significantly (p<0.05) affected by breed and sex. Likewise, weaning weight and weight at 5 months was found to be significantly affected by sex and breed. Mean for ultrasound measurements of eye muscle properties were highly significant (p<0.001; p<0.01) for eye muscle depth at 12 rib, eye muscle area at 12 rib and 3-4 lumbar vertebrae, and for backfat thickness in the two points; significant differences (p<0.05) were found for eye muscle depth and area at 3-4 lumbar vertebra, but no significant differences were found for eye muscle perimeter (p>0.05). The lamb sex and breed was found to be significant variable for eye muscle area and the lamb diet for eye depth at 3-4 lumbar vertebrae. Regarding the phenotypic correlations between ultrasound measurements with weight at 5 months, from a total of 45 traits couples, 46.66% are small correlation (0.00-0.30), 26.67% are medium to high correlations (0.31- 0.60) and high correlations recorded 26.67% (0.61-1.00). Due to the lack of labor in agriculture, in the last years many sheep breeders do not want to milk the sheep, they prefer to let the lambs graze along with their mothers, so that the lambs are marketed at the age of 4-5 months. It is extremely difficult to take measurements on carcasses in these regions as lambs are mainly marketed or slaughtered as small groups or individually and abattoirs do not record any measurements on carcasses characteristics. In this situation, information on body composition of lambs can be obtained practically by ultrasonic measurements on live animals. When combined in a breeding program with lamb weight at 5 months or market weights, these measurements will provide a way to increase both meat yield and the quality of lambs. [ABSTRACT FROM AUTHOR]

Objective: To investigate the association of several obesity anthropometric indices, including body mass index (BMI), waist circumference (WC) and waist-hip ratio (WHR), with carotid intima media thickness (CIMT) in local Chinese populations; to examine the variation of CIMT with age in local Chinese populations. Methods: This is a cross-sectional prospective study in 184 Chinese patients in a local Accident and Emergency Department (AED) aged = 18 years without risk factors for atherosclerosis. Subjects' common carotid artery intima media thickness was measured with a 4.5-15MHz linear ultrasound transducer at a point 10mm proximal to the carotid bulb. All subjects' age, gender, anthropometric (WC and hip circumference (HC) from which WHR was calculated, weight and height from which BMI was calculated) and CIMT values were recorded on a pro forma. Descriptive and inferential statistic methods such as t test and chi-square were carried out. Correlation coefficients were used to determine the relationship between age, BMI, WC, WHR, and CIMT. Results: The right, left, and average CIMT of both sides in our study subjects were 0.55 ± 0.14mm, 0.58 ± 0.15mm, and 0.56 ± 0.14mm respectively, with no significant difference between the right and left sides (p > 0.05). The left, right and average CIMT did not differ significantly between men and women (p>0.05). WC (r = 0.313, 0.271, 0.309; all p < 0.001) and WHR (r = 0.359, 0.312, 0.355; all p < 0.001) showed moderate positive correlations with right, left, and average CIMT. BMI (r = 0.188, 0.160, 0.184; p < 0.05) showed weak positive correlations with right, left, and average CIMT. Correlations between BMI with right, left, and average CIMT in male was found to be stronger than in female. There was a linear relationship between age and CIMT (r = 0.557, 0.509, 0.564 for right, left and average CIMT respectively; all p < 0.001), for which in female was stronger than in male. Conclusions: Ultrasonic CIMT measurement can be useful for refining CVD risk assessment in some symptomatic patients. It detects subclinical vascular disease and identifies patients at increased risk of CVD, and thus aids in risk stratification and patient management especially in the primary care setting and the AED. This study provides evidence of a positive association of WC, WHR, BMI and age with CIMT in Hong Kong Chinese populations. The association of WC and WHR was found to be stronger than that of BMI with CIMT. WC and WHR may be used as supplemental indices for redefining obesity and an alternative tool for further refining discrimination of early atherosclerotic burden. CIMT increases with age, and this factor should be considered in the sonographic assessment of CIMT. [ABSTRACT FROM AUTHOR]

It is important to monitor the roll bite interface during metal rolling to maintain the product size and homogeneity so as to minimize the material wastage. However, the harsh nature of cold rolling makes installation of sensors in metal roll for industrial applications difficult. The present study used a novel ultrasonic measurement technique whereby an ultrasonic signal went through an external sensor layout arrangement to study the metal-roll interface. The reflection coefficient obtained from the roll-strip interface at 0° to the roll surface (normal ultrasonic measurement technique) and 19° (oblique ultrasonic measurement technique) were modelled and experimentally investigated on an instrumented pilot metal rolling mill. Variances of 6.4% and 8.8% were obtained in the reflection coefficient of the techniques from experimental and modelling approaches, respectively. This showed that both techniques could be used to study the effect of the angle of incidence wave on the reflection coefficient. [ABSTRACT FROM AUTHOR]

Lithium-Ion batteries are used in ever more demanding applications regarding operating range and safety requirements. This work presents a series of high-temperature abuse experiments on a nickel-manganese-cobalt oxide (NMC)/graphite lithium-ion battery cell, using advanced in-operando measurement techniques like fast impedance spectroscopy and ultrasonic waves, as well as strain-gauges. the presented results show, that by using these methods degradation effects at elevated temperature can be observed in real-time. These methods have the potential to be integrated into a battery management system in the future. Therefore they make it possible to achieve higher battery safety even under the most demanding operating conditions. [ABSTRACT FROM AUTHOR]

Using high frame-rate ultrasound and ¡1 μ m sensitive motion tracking we previously showed that shear waves at the surface of ex vivo and in situ brains develop into shear shock waves deep inside the brain, with destructive local accelerations. However post-mortem tissue cannot develop injuries and has different viscoelastodynamic behavior from in vivo tissue. Here we present the ultrasonic measurement of the high-rate shear shock biomechanics in the in vivo porcine brain, and histological assessment of the resulting axonal pathology. A new biomechanical model of brain injury was developed consisting of a perforated mylar surface attached to the brain and vibrated using an electromechanical shaker. Using a custom sequence with 8 interleaved wide beam emissions, brain imaging and motion tracking were performed at 2900 images/s. Shear shock waves were observed for the first time in vivo wherein the shock acceleration was measured to be 2.6 times larger than the surface acceleration (95 g vs. 36 g). Histopathology showed axonal damage in the impacted side of the brain from the brain surface, accompanied by a local shock-front acceleration of > 70 g. This shows that axonal injury occurs deep in the brain even though the shear excitation was at the brain surface, and the acceleration measurements support the hypothesis that shear shock waves are responsible for deep traumatic brain injuries. [ABSTRACT FROM AUTHOR]

Objective: The purpose of this study was to evaluate the usefulness of ultrasound (US) volume measurement of the cervical lymph nodes for diagnosing nodal metastasis in patients with head and neck cancer using a node-by-node comparison.Methods: Thirty-four consecutive patients with head and neck cancer from one tertiary university hospital were prospectively enrolled from 2012 to 2017. Patients with histologically proven squamous cell primary tumors in the head and neck region scheduled to undergo a therapeutic neck dissection were eligible. For each patient, 1-4 target lymph nodes were selected from the planned neck dissection levels. Lymph nodes with thickness >20 mm or in a cluster were excluded. Node-by-node comparisons between the pre-operative US assessment, the post-operative actual measurements and histopathological results were performed for all target lymph nodes. Quantitative measurements, such as three diameters, ratios of the three diameters and volume were analyzed in this study. Lymph node volume was calculated using the ellipsoid formula.Results: Patients comprised 28 men and 6 women with a mean age of 60.0 years (range, 29-80 years) at the time of surgery. In total, 67 target lymph nodes were analyzed in this study and the thickness ranged from 3.9 to 20.0 mm (mean 8.0 mm). There was a strong correlation between the US volume and post-operative actual volume (ρ = 0.87, p < 0.01). The US volume measured 2156 ± 2156 mm3 for the tumor positive nodes, which was significantly greater than the US volume of 512 ± 315 mm3 for tumor negative nodes (p < 0.01). Significant differences between tumor positive and tumor negative nodes were found in five variables (volume, thickness, major axis, minor axis and ratio of minor axis to thickness) for total lymph nodes. To identify predictors of lymph node metastasis, ROC curves of the US variables of target lymph nodes were compared, of which 4 variables were considered acceptable for predicting the lymph node metastasis: volume (AUC 0.86), thickness (AUC 0.86), major axis (AUC 0.79), and minor axis (AUC 0.79) for total lymph nodes. The optimal cut-off level for US volume in total lymph nodes was found to be 1242 mm3, whereby a 62% sensitivity and 98% specificity was reached (likelihood ratio: 25.2).Conclusion: Pre-operative ultrasonic volume measurement of the cervical lymph nodes was useful for early detection of cervical nodal metastasis in head and neck cancer. [ABSTRACT FROM AUTHOR]

Concentration of H 2 gas in a stainless steel (SUS) pipe is measured by using ultrasound from the exterior of a pipe without making a hole. Gas concentration is calculated by the variation of ultrasound speed detected. A sound absorbing material is put on the outer surface of the SUS pipe to reduce the ultrasonic signal noise circulating through the shell of the SUS pipe. Then it is possible to measure the gas concentration by observing the airborne signal passing through the SUS pipe. Propagation of ultrasound wave in SUS pipe is also simulated by the finite-difference-time-domain method that could explain the ultrasound propagation signals in the SUS pipe. • Airborne signal was observed by pasting sound absorbing material on the pipe surface. • Gas concentration was measured using ultrasound from exterior of a metal pipe. • Noise signal was canceled using two transmitters by simulation. [ABSTRACT FROM AUTHOR]

Highlights • A UT damage index for inspection of hysteretic seismic dampers has been validated. • A strong linear relationship UT index – ID mechanical index has been demonstrated. • The traditional mechanical index ID can be determined indirectly from UT index. • UT damage index behavior is scarcely affected by the loading pattern. • UT damage index works well above 20 dB of signal noise ratio. Abstract Energy dissipation is an innovative strategy for the passive protection of buildings and infrastructures against earthquakes. It entails installing special devices called dampers in a construction. They dissipate most of the energy input by an earthquake, thus keeping the main structure basically undamaged. Among the different types available, the so-called hysteretic dampers are commonly used to dissipate energy through plastic deformations in metallic parts of the device. Several moderate ground motions or even a single severe earthquake would not exhaust the capacity of the dampers, but they do cause damage —namely, plastic deformations in the device. Therefore, continuous or periodic inspections of the damper are required in order to decide upon its eventual replacement. The present work proposes Ultrasonic Testing (UT) as a method to quantify the damage upon hysteretic dampers subjected to cyclic loadings. To this end, several hysteretic dampers made of stainless steel were subjected to different patterns of quasi-static (low-frequency) cyclic loads that caused diverse levels of damage. Each damper underwent UT before and after the cyclic loading. UT parameters related to ultrasound waves including spectral amplitude and spectral energy were properly analyzed at each damage level. Based on these parameters, a UT damage index is put forth. The proposed UT index was then compared with a well-established mechanical damage index, ID, based on decomposing load–displacement curves into the skeleton part and Bauschinger part and computing the corresponding energies. A successful correlation was observed between the mechanical damage index ID and the novel UT index, making the UT technique promising for this particular application. [ABSTRACT FROM AUTHOR]

Highlights • The technique was tested with five substances covering a wide viscosity range. • Newtonian behavior was observed at ultrasonic frequencies for all liquids. • An unexpected oscillatory behavior in the viscosity was observed. • The alternative signal processing methodologies show improvement in accuracy. Abstract This work deals with two alternative methodologies for data post-processing resulting from the ultrasonic shear-wave reflectance method used for liquid viscosity measurement. In the shear-wave reflectance method, the measurement principle is the small transference of energy to the liquid when the wave strikes a solid–liquid interface, causing a detectable change in the reflection coefficient. A measurement cell that uses mode conversion for the generation of the shear waves was employed and samples of five different substances were tested, covering a viscosity range of three orders of magnitude. Ultrasonic results were compared to the values obtained by conventional viscometry. Despite the wide range of viscosity and the different nature of the liquids, Newtonian behavior was observed with all samples at the working frequencies. This can be concluded from the coincidence between the values obtained by ultrasound and by the rotational viscometer. However, the viscosity values show an oscillating behavior when calculated for different frequencies along the band of the transducer. This oscillating behavior induces big errors when the viscosity is calculated at a single frequency, forcing the development of alternative methodologies. Two methodologies that calculate the reflection coefficient in a frequency band instead of a single frequency were analyzed, showing more accuracy and precision. [ABSTRACT FROM AUTHOR]

The article describes the method of controlling the recovered grade based on measuring the intensity of volume ultrasonic oscillations and Lamb waves covering a fixed distance through the test medium and on a metal plate contacting the test medium at various time points of deliberate motion of ground materials. The authors suggest a method of determining density of ground ore particles in the pulp periodically after isolating the pulp flow in the vertical part of the measuring vessel based on measuring attenuation change values in Lamb waves covering a fixed distance on a plate contacting the medium under study and high frequency volume ultrasonic oscillations that have come through it within a certain time period. There are given dependencies of amplitudes of measuring channels based on volume ultrasonic oscillations and surface Lamb waves, size distribution according to solid phase pulp particles for various types of ores under study, a set of curves for determining the recovered grade with regard to various types of ores under study. [ABSTRACT FROM AUTHOR]

• Effect of various superabsorbent polymers on the self-healing ability. • Benchmarking of air-coupled ultrasound for self-healing monitoring through a comparison with coupled ultrasonic measurements. • Ultrasonic velocity and attenuation follow crack closure as measured by microscopy. Self-healing cementitious composites including superabsorbent polymers (SAPs) have been studied as an alternative to costly, labour-intensive repairs. Whereas the assessment of the healing ability can be performed through a variety of testing methodologies, an in-situ evaluation requires the adoption of a non-destructive technique in order to maintain the present infrastructure. Additionally, the assessment method should be easily applicable for reasons of time efficiency. Thanks to their sensitivity to the elastic properties, ultrasonic waves have enabled the evaluation of the regained mechanical performance, without interfering with the microstructure. While coupled ultrasonic measurements are an established procedure, the use of air-coupled ultrasound provides the advantage of omitting the transducers' coupling. As the coupling is a time-consuming task and imposes a certain variability between performed measurements, the adoption of air-coupled ultrasound would lead to a significant improvement of the evaluation method. Therefore, a comparison between both techniques using various mortar mixtures was performed. [ABSTRACT FROM AUTHOR]

The application of planar Edge-Illumination X-ray Phase-Contrast imaging (EI-XPCi) for the non-destructive quantification of porosity in carbon fiber reinforced polymer (CFRP) specimens, a significant concern in aerospace applications, was investigated. The method enables fast, planar (2D) scans providing access to large samples. A set of woven CFRP plates with porosity content ranging from 0.7% to 10.7% was examined. In addition to standard X-ray attenuation, EI-XPCi provides differential phase and dark-field signals, sensitive to inhomogeneities and interfaces at scales above and below the system spatial resolution, respectively. The correlation with the porosity content from matrix digestion obtained from the dark-field signal was comparable to that from ultrasonic attenuation. The novel analysis of the standard deviation of differential phase (STDP), sensitive to inhomogeneities above the system resolution (approximately 12 μm), resulted in a very high correlation (R2 = 0.995) with the matrix digestion porosity content, outperforming ultrasonic attenuation measurements. [ABSTRACT FROM AUTHOR]

It is well known that ultrasound images are cost-efficient and exhibit hassle-free usage. However, very few works have focused on exploiting the ultrasound modality for lesion diagnosis. Moreover, there is no reliable contribution reported in the literature for diagnosing pelvic lesions from the pelvic portion of humans, especially females. While few contributions are found for diagnosis of lesions in the pelvic region, no effort has been made on enhancing the images. Inspired from the neural network (NN), our methodology adopts deep belief NN for enhancing the ultrasound image with pelvic lesions. The higher-order statistical characteristics of image textures, such as entropy and autocorrelation, are considered to enhance the image from its noisy environment. The alignment problem is considered using skewness. The proposed method is compared with the existing NN method to demonstrate its enhancement performance. [ABSTRACT FROM AUTHOR]

There is a growing need for nondestructively evaluate the integrity of trees and wooden structural elements. Such an investigation can be performed with the use of different test methods. Nevertheless, in order to yield acceptable results, the test methods should consider the anisotropic nature of the wood, which includes the shape of the annual rings, and also the pith location in the cross-section. This paper presents a new method to determine the pith location of a tree or structural element made of timber or lumber based on ultrasonic tomography readings. [ABSTRACT FROM AUTHOR]

Ultrasonic analysis has long been used as a diagnostic tool for materials and medicine, and measurements that are able to detail internal structure are often desirable. Peak density has previously been used as an assessment for tissue pathology. This quantity has potential for use in the study of tissue and soft materials. However, the use of this parameter is still in its early stages, and the signal processing techniques used are limited. In this work, other signal processing methods commonly used in ultrasonic measurement are applied to the resulting ultrasound pulses transmitted through a soft phantom material to study their effects on peak density calculations. This study examines the outcomes due to the selection of pulse width, the use of standard window functions, and spectral normalization using a reference spectrum. The consequences are assessed through the inspection of individual frequency spectra as well as two dimensional images based upon the peak density parameter. It was found that peak density was highly dependent on the window function employed and was also subject to the pulse width. Spectral normalization was found to have little effect on peak density calculations. [ABSTRACT FROM AUTHOR]

The present work highlights the effect of ultrasound on enzymatic synthesis of isobutyl propionate, a rum flavor by esterification of isobutanol and propionic acid in non-aqueous, solvent free system (SFS) using Fermase CALB™10000. The optimization study for different variables in presence of ultrasound showed a maximum conversion of 95.14% at 60 °C temperature, 4% w/w enzyme dose, 1:3 acid:alcohol ratio, 40 W power, 25 kHz frequency, 50% duty cycle and 150 rpm speed in 3 h as compared to 10 h of conventional method. The optimal enzyme loading was reduced to 4% w/w using ultrasound irradiation compared to 5% w/w of conventional. The efficiency of enzyme improved notably and can be reused up to seven cycles preserving its former activity. The application of ultrasound greatly enhanced esterification reactions by maintaining enzyme stability and improving the production yield. Moreover, owing towards a green approach, the synthesis is carried out in SFS for development of lucrative flavor ester. Bisubstrate kinetic models like random bi-bi, ping pong bi-bi and ordered bi-bi were applied to the experimental data using non-linear regression analysis. The experimental data and kinetic study revealed that reaction obeyed Ping-Pong bi-bi model with kinetic parameters, V max = 50.0 M/min/g catalyst, K A = 4.87 × 10 −2 M, K B = 9.06 × 10 −4 M, K iA = 9.8 × 10 −1 M, K iB = 1.05 × 10 −3 M & SSE = 2.74 × 10 −4 for lipase catalysed synthesis of isobutyl propionate under ultrasound with inhibition by both acid and alcohol. [ABSTRACT FROM AUTHOR]

An ultrasonic viscometer was used to measure the circumferential viscosity variation in a journal bearing noninvasively. This sensing technique is based on the reflection of a shear wave at a solid–liquid boundary that depends on the viscosity of the liquid and the acoustic properties of the solid. Very little ultrasonic energy can propagate into the oil at a metal–oil interface because the acoustic mismatch is significant. Interleaving a matching layer between the metal and the lubricant enables accurate ultrasonic viscosity measurements (M. Schirru, et al., Tribology Leters, Vol. 60, No. 3, 2015). This technique has been used to build a miniaturized ultrasonic viscometer that is accommodated inside a journal to obtain the circumferential viscosity profile. Four viscosity regions are identified due to the variations in the localized temperatures and loads. The results are compared with the isothermal solution of the Reynolds equations for hydrodynamic lubricated bearings. The ultrasonic viscometer locates the angle at which the maximum load occurs and the length of the loaded contact with good accuracy. Finally, the viscosity results are used to estimate the frictional power losses. It is shown that over 70% of the total losses in the journal bearing occur in the region where the load is maximum. [ABSTRACT FROM AUTHOR]

• An improved ultrasonic reflection coefficient phase model is proposed for calculating the analytic solution to the lubricant film thickness. • The lubricant film thickness in both the spring model region and the blind region is measured in systems with different material properties of the solid layers. • The influence of the material properties of the solid layers on the reflection coefficient phase is investigated. An improved ultrasonic reflection coefficient phase model is proposed for lubricant film thickness measurement with consideration to the influence of the solid layers. In the model, the theoretical relation of the lubricant film thickness to ultrasonic reflection coefficient phase is established, which is used for effectively determining the lubricant film thickness. Furthermore, the proposed model is verified by both the finite element analysis and experiments. The results show that the lubricant film thickness ranges between 2 μm and 45 μm can be measured by using the proposed model, which covers both the spring model region and the blind region. In addition, at a small film thickness, the reflection coefficient phase is significantly affected by the acoustic impedances in both solid layers. However, the reflection coefficient phase is dominantly affected by the solid layer in the neighbourhood of the incidence source at a large film thickness. [ABSTRACT FROM AUTHOR]

• The time of flight of an ultrasonic wave is related to the velocity and the angle. • Results are reported for airflow velocities up to 460 km/h. • Propagation of ultrasonic waves occurs in the boundary layer. • Simulations based on ray tracing code and an analytical waves propagation model are in agreement with experiments. In this work, a flush ultrasonic probe has been developed for the measurement of the velocity and the angle of attack (AOA) of an aircraft. The probe is made of one emitting transducer located at the center of a rotating stage and several receiving transducers located downstream, all transducers radiating in a normal direction perpendicular to the airflow. The determination of speed and AOA are deduced from the time of flight measurement of an ultrasonic wave between the emitter and the receivers propagating in the boundary layer. Particular attention was paid to the instrumentation as well as to the signal processing to enhance the ultrasound transmission and reception and to increase the signal-to-noise ratio. Results are reported for airflow velocities up to 127 m/s (460 km/h) both as a function of the emitter-receiver distance and as a function of the wind incidence angle. These experimental results are compared to simulations that estimate the time of flight between a source and a receiver. It is shown that ultrasonic waves propagate in the boundary layer and that the simulation code can predict the time of flight as a function of the distance and the angle. [ABSTRACT FROM AUTHOR]

Background: The aim of this prospective study was to investigate the success of ultrasound in pediatric patients in determining the appropriate sized cuffed endotracheal tube and to compare the results with conventional height-based (Broselow) tape and age-based formula tube size. Methods: One hundred and fifty-two children of 1-10 years of age, who received general anesthesia for adenotonsillectomy were enrolled to the study. In all participants, the transverse diameter of the subglottis was measured with ultrasound during apnea. An endotracheal tube was chosen with the outer diameter matched to the measured subglottic airway diameter. An age-based (Motoyama-Khine) and height-based (Broselow) endotracheal tube size was calculated. If there was resistance to passage of the tube into the trachea or an airway pressure >25 cmH20 was required to detect an audible leak, the endotracheal tube was replaced with internal diameter of 0.5 mm smaller. If there was an audible leak at airway pressure <10 cmH2O, or peak pressure >25 cmH20 or a cuff pressure > 25 cmH2O was required to seal, the tube was changed to the 0.5 mm larger internal diameter. Best-fit tube internal diameter was the resultant tube internal diameter that met the previously stated conditions. The need for endotracheal tube replacement and peak airway pressure were recorded. Results: The internal diameter of ultrasound determined tube was the same as best-fit tube in 88% of children. Endotracheal tube was replaced in 15 patients with a one size larger, and in three patients with one size smaller tube. Using Bland-Altman analysis, a better agreement was observed with ultrasound measurement rather than height-based estimation and age-based formulas. Conclusion: Our findings show that subglottic diameter measured by ultrasound appears to be a reliable predictor for the assessment of the subglottic diameter of the airway in estimating appropriate size pediatric endotracheal tube. [ABSTRACT FROM AUTHOR]

Estimating deterministic single-valued damage parameters when evaluating the actual health state of a material has a limited meaning if one considers not only the existence of measurement errors, but also that the model chosen to represent the damage behavior is just an idealization of reality. This paper proposes a multilevel Bayesian inverse problem framework to deal with these sources of uncertainty in the context of ultrasound-based damage identification. Although the methodology has a broad spectrum of applicability, here it is oriented to model-based damage assessment in layered composite materials using through-transmission ultrasonic measurements. The overall procedure is first validated on synthetically generated signals and then evaluated on real signals obtained from a post-impact fatigue damage experiment in a cross-ply carbon-epoxy laminate. The evidence of the hypothesized model of damage is revealed as a suitable measure of the overall ability of that candidate hypothesis to represent the actual damage state observed by the ultrasound, thus avoiding the extremes of over-fitting or under-fitting the ultrasonic signal. [ABSTRACT FROM AUTHOR]

This work studied the effects of ultrasound treatment on the process of hydration of corn kernels, evaluating both the water uptake and its starch properties. For that, an ultrasound bath at a frequency of 25 kHz and volumetric power of 41 W/L was used. Furthermore, different treatments were applied in order to determine the mechanisms of enhancement of the hydration process (direct or indirect effects), by studying the hydration kinetics and the microstructure of the kernels. Finally, the rheological, thermal and structural properties of the starch extracted from the corn kernels (hydrated with and without ultrasound) were evaluated. Due to the particular behavior of the corn kernels during hydration, a two terms semi-empirical equation was proposed to explain the process, which contains two simultaneous ways related to the different mechanisms of water influx. Ultrasound significantly improved the hydration process, increasing water uptake and decreasing the process time by ∼35%. In contrast to other grains, it was demonstrated that the enhancement of the process was only due to the direct effects (inertial flow and sponge effect) and not the indirect effects (micro-channels formation). Finally, it was demonstrated that the ultrasound treatment did not alter the properties of the starch. As a conclusion, it was shown that the corn kernels can be quickly hydrated using ultrasound treatment without modifying any of the properties of the starch, this being highly desirable for the starch industry. [ABSTRACT FROM AUTHOR]

Mathematical simulation is used to estimate the error in ultrasonic-echo measurements of the thickness of objects made of inhomogeneous materials with structural noise and frequency-dependent attenuation of ultrasound taken into account. Empirical formulas are derived for estimating the minimum measurement error. [ABSTRACT FROM AUTHOR]

Wind turbine gearbox failures, many of which result from load-driven rolling element bearing failures, account for long downtimes and high maintenance costs. Non-invasive, in-situ measurement of bearing roller loads using ultrasound facilitates better understanding of the load history and failure mechanisms these gearbox bearings experience. In this study, ultrasonic load measurements from an instrumented high-speed shaft bearing were compared against results from a static multibody simulation. Measurements taken under steady operating conditions were found to agree well with the model. After quantification of the error in ultrasonic measurements the model enabled identification of load outliers which were attributed to transient events. Over- and under-loading instances may act to promote a variety of failure mechanisms, leading to premature bearing failure. • Ultrasonic sensors successfully inferred wind turbine HSS bearing load from signals. • Measurements agreed well with results from a model of the turbine drivetrain. • Ultrasound accuracy was load dependent and ranged from ± 0.4–1.0 kN. • Low and high load outliers were attributed to transient loading events. • A slight shift in bearing loaded zone were observed through sensor load ratio. [ABSTRACT FROM AUTHOR]

An ultrasonic method, which apply in the particles flocculent settling, was proposed and studied based on the ECAH model. Comparing with the interface settling method, microscopic imaging and online sampling method, the phenomenon of flocculation and settling was observed accordingly and the settling stages were analyzed simultaneously by both the interface settling velocity and ultrasonic attenuation coefficient. The correlation between the process of flocculation and ultrasonic parameters was established accordingly, which provided data support for the application of ultrasonic technique to the online detection of kaolinite particle flocculent settling processes. [Display omitted] • An ultrasonic method, which apply in the particles flocculent settling process, was proposed and studied based on the ECAH model. • The duration of each settling stage and it's change rate were analyzed simultaneously by both the interface settling velocity and ultrasonic attenuation coefficient. • The presented method is suitable for online monitoring particles flocculent settling process in high turbidity water. In order to implement real-time monitoring of flocculent settling processes, an ultrasonic method based on the ECAH model was proposed and studied, particularly by considering the influence of particle irregularity on sound attenuation. Numerical simulations were conducted to evaluate the influence of critical physical parameters' variation on the attenuation coefficient. Meanwhile, an integrated experimental system including ultrasonic measurement, interface settling velocity measurement, microscopic imaging and online sampling methods was established. The experiments of kaolinite particle suspensions with four different initial mass concentrations were carried out, and the phenomenon of flocculation and settling was observed accordingly. The duration of each settling stage and its change rate were analyzed simultaneously by both the interface settling velocity and ultrasonic attenuation coefficient. The analysis results show that for the same flocculent settling stage, the relative deviation of duration obtained by two methods above were 0%, 7.32%, −10.57%, 1.62% and 1.63%, respectively. The mechanisms and characteristics of each stage in the precipitation process were discussed in detail. At the same time, the volume concentrations obtained by ultrasonic method were compared with the results of weighing after on-line sampling. The deviations under the four initial mass concentrations were 18.6%, 12.1%, 11.0% and 13.2% respectively. The correlation between the process of flocculation and ultrasonic parameters was established accordingly, which provided data support for the application of ultrasonic technique to the online detection of kaolinite particle flocculent settling processes. [ABSTRACT FROM AUTHOR]

A customised convolutional neural network (CNN) architecture is proposed in this paper to make estimations about the thickness values (minimum and mean) of corroded profiles from an ultrasonic time-series measurement (A-scan). The CNN architecture is determined after a hyper-parameter optimisation which leads to the best performing network. The model is trained using synthetic data and tested on both synthetic and experimental datasets. A comparison is made with (1) a state-of-the-art network for time series analysis and (2) conventional thickness estimation techniques such as peak envelope and threshold crossing. The proposed network provides an accurate estimation of the thickness values and outperforms the conventional techniques in both synthetic and experimental datasets. When compared to a conventional threshold-crossing technique for minimum thickness prediction, the proposed network is more consistent and less sensitive to changes in the threshold. • A CNN architecture for thickness estimation of corroded profiles is proposed. • The deep learning model uses raw ultrasonic time series as input. • The method is trained using FE simulated data from a wide parameter space. • More accurate and reliable thickness prediction than conventional techniques. [ABSTRACT FROM AUTHOR]

Kidney ultrasound is one of the basic procedures in the practice of a urologist. Apart from the location and the size, description of renal morphology should contain the thickness of the anterior lip parenchyma in a transverse section and the location of possible narrowings. Uneven outline of the kidney is a sign of past inflammatory conditions. In the case of the pelvicalyceal system dilation, it is advised to specify the dimensions of the pelvis and calyces. Convex shape of the calyces proves elevated pressure within the pelvicalyceal system. Hydronephrosis is present when urinary retention has led to thinning the renal parenchyma. In each case, one should identify the reason for urinary retention in the upper urinary tract. Urinary retention on both sides requires one to exclude urinary bladder tumor, it may also be caused by a benign prostatic hyperplasia. Ultrasound examination is a sensitive method of renal stones detection, regardless of their chemical composition. Cyst description in an ultrasound image should cover its morphological features, differentiating between the so-called simple or complex cysts. In the case of a solid lesion, ultrasound makes it possible to detect parenchymal lesions usually starting with the size of 2-2.5 cm. It enables one to particularly diagnose angiomyolipomas. As regards the remaining parenchymal lesions, differentiation of the lesion nature is impossible. In some cases of angiomyolipoma, when it contains bleeding areas present and when it is deficient in adipose tissue, it resembles adenocarcinoma. It is necessary that the description includes the exact location, especially the dimensions and relation of the tumor to the renal sinus. In the case of larger lesions, respiratory motion of the kidney, the condition of the adrenal gland and the presence of enlarged lymph nodes should be controlled. Additionally, one should evaluate the renal vein and inferior vena cava in terms of a neoplastic plug presence. [ABSTRACT FROM AUTHOR]

In this paper we present a new method to obtain the density of solid composites using ultrasound. The method exploits the relation between density and acoustic impedance and only requires the measurement of a reference signal form the interface water-air. Once made in a controlled environment, it can be used for any material, and does not require any additional measurement or set-up, so that with a simple calculus it can be used with automatic ultrasonic measurements to calculate the density and therefore elastic constants of the composite for its complete characterization. The method is applied to 3 different materials: two composites based on epoxy and polyester resins respectively with unknown final properties and a common methacrylate sample used as reference. Results show good concordance between obtained and expected results. [ABSTRACT FROM AUTHOR]

Background: Optic nerve sheath diameter (ONSD) measurement using ultrasound has been proposed as a rapid, non-invasive, point of care technique to estimate intra-cranial pressure (ICP). Ultrasonic measurement of the optic nerve sheath can be quite challenging and there is limited literature surrounding learning curves for this technique. We attempted to develop a method to estimate the reliability learning curve for ONSD measurement utilizing a unique definition of reliability: a plateau in within-subject variability with unchanged between-subject variability. Methods: As part of a previously published study, a single operator measured the ONSD in 120 healthy volunteers over a 6-month period. Utilizing the assumption that the four measurements made on each subject during this study should be equal, the relationship of within-subject variance was described using a quadratic-plateau model as assessed by segmental polynomial (knot) regression. Results: Segmental polynomial (knot) regression revealed a plateau in within-subject variance after the 21st subject. However, there was no difference in overall mean values [3.69 vs 3.68 mm ( p = 0.884)] or between-subject variance [14.49 vs 11.92 ( p = 0.54)] above or below this cutoff. Conclusions: This study suggests a significant finite learning curve associated with ONSD measurements. It also offers a unique method of calculating the learning curve associated with ONSD measurement. [ABSTRACT FROM AUTHOR]

An accuracy increasing method of processed ore mineral varieties determination based on subtractive clustering of its features with the correction of fuzzy rules region dimensions by the evaluation of intensity dispersion of high-frequency volume ultrasonic vibrations, which passed a fixed distance in a controlled volume of pulp is proposed. [ABSTRACT FROM AUTHOR]

'Acute abdomen' includes spectrum of medical and surgical conditions ranging from a less severe to life-threatening conditions in a patient presenting with severe abdominal pain that develops over a period of hours. Accurate and rapid diagnosis of these conditions helps in reducing related complications. Clinical assessment is often difficult due to availability of over-the-counter analgesics, leading to less specific physical findings. The key clinical decision is to determine whether surgical intervention is required. Laboratory and conventional radiographic findings are often non-specific. Thus, cross-sectional imaging plays a pivotal role for helping direct management of acute abdomen. Computed tomography is the primary imaging modality used for these cases due to fast image acquisition, although US is more specific for conditions such as acute cholecystitis. Magnetic resonance imaging or ultrasound is very helpful in patients who are particularly sensitive to radiation exposure, such as pregnant women and pediatric patients. In addition, MRI is an excellent problem-solving modality in certain conditions such as assessment for choledocholithiasis in patients with right upper quadrant pain. In this review, we discuss a multimodality approach for the usual causes of non-traumatic acute abdomen including acute appendicitis, diverticulitis, cholecystitis, and small bowel obstruction. A brief review of other relatively less frequent but important causes of acute abdomen, such as perforated viscus and bowel ischemia, is also included. [ABSTRACT FROM AUTHOR]